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تنقية جزئية وتوصيف Biosurfactant من بكتريا Bacillus subtilis وتاثيرها على نمو بعض عزلات البكتريا والفطريات

المستخلص: تم الحصول على 102عزلة من العزلات البكتيرية من 40 عينة من عينات الترب الملوثة بالنفط من مختلف المناطق ورشة عمل السيارات، محطات وقود السيارات، مصافي النفط ولخمسة مناطق مختلفة في العراق . خضعت كل هذه العزلات الى الفحص المجهري والخصائص الزرعية ووجد ان 80 عزلة منها تنتمي الى جنس Bacillus ، هذه العزلات خضعت ايضا لاختبارات بايوكيميائية وشخصت بناءا على دراسة rDNA 16S من قبل مجموعتين من البرايمرات (andB16SF B16SR) و(1492R and 27 F) اذ وجد ان 51 عزلة منها تعود الى Bacillus subtilis . تم فحص جميع هذه العزلات من حيث قدرتها على انتاج biosurfactant عن طريق فحص النشاط انحلال الدم على وسط دم الاغنام حيث وجد ان جميع العزلات كانت من النوع تحلل الدم بيتا حيث تم فحصها اعتمادا على قياس الشد السطحي بعد زراعتها في Jacques medium اظهرت النتائج ان 46 عزلة من 51 عزلة كانت منتجة biosurfactant , وقد تم اختيار ثمانية منها تميزت بانتاجها لهذا المركب وهي (S1,S2,S3 S4,S5,S6,S7,S8) حيث كانت العزلة B. subtilis S4 هي الاكفا في الانتاج لذلك اختيرت في الدراسات اللاحقة . تم استخلاص Biosurfactant الخام من العزلات المختارة بواسطة وتنقيته جزئيا باستخدام طريقة Ion exchange chromatography باستخدام DEAE - Cellulose تلاها طريقة Gel filtration chromatography باستخدام Sepharose - 6B . تمت دراسة خصائص المركبات المنقاة واظهرت النتائج ان الوزن الجزيئي biosurfactant التي تنتجهاB.subtilis S4 تراوح بين (1036 - 1058دالتون) من خلال جهاز HPLC - TOF - MS . اظهرت النتائج ان الحد الاقصى لانتاج biosurfactant من العزلة تم بطريقة استخدام زيت الزيتون (3٪) وكبريتات الامونيوم (0.3٪) وKH2PO4 (1.5) غم / لتر، وبدرجة حرارة 30 مº والاس الهايدروجيني (7) وفترة الحضانة لمدة 72 ساعة. وقد تحققت اعلى نسبة للـ biosurfactant بعد مكملات الظروف المثلى الى 0.3 غرام / لتر من الوسط الزرعي . تم اختبارالنشاط البكتيري والفطري للعزلات الثمانية ضد بعض الجراثيم المسببة للامراض، وهي Staphylococcus aureus,Streptococcus pneumonia, Pseudomonas aeruginosa ,Escherichia coli ,Proteus mirabilis, Candida albicans , Candida tropicalis , Candida krusei , Rhizopus oryzae , Aspergillus niger وكانت العزلة الاكثر فعالية هي B.subtilis S4 التي اظهرت وجود نشاط ضد كل مسببات الامراض ماعدا S.pneumonia ,P.aeruginosa ,C.krusei . كما بينت النتائج ان مستخلص العزلة B.subtilis S4 اظهر اعلى تثبيط نموعند التركيز 1500 مايكروغرام / مل وصل الى 24 ملم ضد E.coli، 23 ملم ضد K.aerogenes، 21 ملم ضد S.aureus، 15 ملم ضدC.albicans، 14 ملم ضد P.mirabilis، 11 ملم ضد C.tropicalis، وتثبيط نمو الفطريات، حيث وصل معدل النمو الشعاعي الى 31.9 ملم ضد A.niger و9.7 ملم ضد R.oryzae عند التركيز 2 ملغم / مل. كذلك اظهرت النتائج ان سمية المستخلص B.subtilis خارج الجسم الحي على ذكور الجرذان البيض بلغت حوالي 922 ملغم / كغم وتشير اذ ان الاعطاء اليومي biosurfactant لم تظهراي حالة وفاة في اي جرعة ، ولم تلاحظ اي تغييرات غير عادية في السلوك اوتاثيرات سمية خلال فترة 28 يوما من العلاج. واثبت التحاليل انه ليس هناك اي تاثير سلبي على معايير الدم الفسلجية وهذا يؤكد صحة هذه المستحضرات الحيوية للاستخدام . | About 102 bacterial isolates were obtained from 40 oil contaminated soil samples from various automobile work shop ,cars fuel stations ,oil refineries of five different areas in Iraq. Microscopic examination and cultural characteristics for all isolated were investigated , 80 isolates were found to be related to the genus Bacillus , Bacillus isolates were subjected to the biochemical tests and molecular identification based on the 16S rDNA by two sets of primers (B16SF and B16SR) , (27F and 1492R) of these 80 isolates revealed that 51 of the identified isolates belonged to Bacillus subtilis.All these isolates were screened for their ability for biosurfactant production through blood haemolysis activity on sheep blood agar indicated that all isolates were β - hemolysis while screening depended on measuring the lowering surface tension of cell free supernatant after cultivation in jacques medium which referred that 46 of 51 isolates were biosurfactant producers. Eight isolates were selected for the best biosurfactant producer isolatesCrude biosurfactants produced by the selected isolates were extracted by acid precipitation followed by partially purified with dichloromethane followed by purification and characteristics, the results showed that the molecular weight of biosurfactant produced by B.subtilis S4 ranging between 1036 - 1058 Da . Optimum conditions for biosurfactants production from B. subtilis S4 were determined. Results showed that maximum biosurfactant production from this isolate was achieved by using 3% olive oil , 0.3 % ammonium sulfate and 1.5 g / l Potassium dihydrogen phosphate ,at pH7,30 ºC and incubation period for 72 hrs. Maximum biosurfactant production was achieved after the supplementation of the optimum conditions was 0.3 g/l of culture medium .All of the eight isolates were tested for antimicrobial activity against twelve pathogenic microorganisms : Staphylococcus aureus ,Streptococcus pneumonia,Pseudomonas aeruginosa ,Escherichia coli ,Proteus mirabilis Klebsiella aerogenes,Candida albicans,C.tropicalis,C. krusei , Rhizopus oryzae , Aspergillus niger and Penicillium notatum.The most effective isolates were B.subtilis S4 which showed antimicrobial activity against some tested pathogens except S.pneumonia ,P. aeruginosa ,C.krusei and P.notatum.The results indicated that S4 culture extract showed high growth inhibition zone in concentration 1500 µg /ml reached to 24 , 23, 21, 15, 14 and 11 mm against E.coli , K.aerogenes , S.aureus , C.albicans, P.mirabilis,C.tropicalis respectively and high reduction in of radial growth of the fungi reached to 31.9 and 9.7 mm in A.niger and R.oryzae respectively at 2 mg /ml concentration .Study in vivo potential toxicity of B.subtilis lipopeptide biosurfactant towards male rat was evaluated. An LD50 value was determined to be about 922 mg / kg. Results show that daily administration of biosurfactant did not show any death cases at any dose. Also, no unusual changes in behavior and no intoxication were observed during the 28 days period of treatment. Analysis proved that there were no significant adverse effect on hematological parameters and this confirms the validity of those biopharmaceuticals on body of mammals.
الصفحات الاولى:
مكان الجامعة: النجف
اللغة: الانكليزية
الجامعة: جامعة الكوفة - كلية العلوم
الدرجة: دكتوراه
الموضوع الدقيق: الاحياء المجهرية - البكتريا
السنة: 2016
الموضوع العام: علوم الحياة
اسم المشرف: فاطمة عبد الحسين مجبل التميمي
اسم المؤلف: غـفـران فـلـيـح عـبد الـحـسـن عـزيـز الجـبـوري

دراسة جزيئية ومناعية لفايروس النورو والفايروس الغدي نمط 40 و41 في الاطفال المصابين بالاسهال Molecular and Immunological Study of Norovirus and Adenovirus types 40 and 41 in Diarrheic Children

المستخلص: هدفت هذه الدراسة الى التحري عن فايروسي النورو والفايروس الغدي نمط 40 / 41 في الاطفال المصابين بالاسهال واجراء تحليل لمعدل الاصابة وطبيعتها ودراسة الطبيعة الجزيئية للفايروسين وكذلك التحري عن قدرة الفايروسين على حث الجهاز المناعي وتحديد بعض الحركيات الخلويه عند الاطفال المصابين بالفايروسين.بالاضافة الى دراسة بعض ملامح الاصابه مثل تغاير الفصول والعمر وتحديد افضل الطرق لتشخيص الفايروسين. اجريت الدراسة الحالية في محافظة النجف الاشرف /مستشفى الزهراء التعليمي للولادة والاطفال خلال الفترة من كانون الثاني2014 الى كانون الاول 2014 والتي تضمنت 314 عينه من البراز والدم من الاطفال المصابين بالاسهال والذين تتراوح اعمارهم بين شهر الى خمسة سنوات.حيث اعتمد التحري في عينات البراز استخدام اختبار الكروماتوغرافيا المناعي السريع للكشف عن المستضدات الفايروسية للفايروسين النورو والغدي نمط 40 / 41.كما تم تاكيد العينات الموجبة بواسطة تقنية PCR Real Time لفايروس النورو تقنية PCR للفايروسالغدي نمط40 / 41،والتي اظهرت فيها النتائج بان معدل الاصابة كان 11.7% لفايروس النوروو8.9% للفايروس الغدينمط 40 / 41.كذلك تم فحص العينات الموجبة بواسطة المجهر الالكتروني والتي بينت مظهر للفايروسين في عينات البراز . وتشير الدراسة الى ان التقنيات الجزيئية المستخدمة في فحص العينات هي الاكثر كفاءة للتشخيص الروتيني للفايروسين مقارنة مع المجهر الالكتروني لتشخيص عينات الاسهال.وطبقا للفئات العمرية ،اظهرت النتائج ان الفئة العمرية 13 - 24 شهر سجلت ارتفاع عالي للاصابة بالفايروسين النورو والغدينمط 40 / 41.الحالات الايجابية كانت بين الاطفال الذين يتغذون على الحليب الجاف الاصطناعي (31 حاله) مقارنة مع الرضاعة الطبيعية من الام (14 حاله).اما نتائج الاعراض السريرية في الاطفال المصابين بالفايروسين فاظهرت ان كل الحالات تبين وجود اسهال من النوع المائي المخاطي وبنسبة 100% يليها الالم البطن بنسبة 94.5% و82.1 %،التقيؤ بنسبة 81 % و78.5 % واخيرا الحمى بنسبة 78.3% و71.1 % لكلا من النورو والغدي نمط 40 / 41 على التوالي. كما كشفت الدراسة الحالية بان معدل الاصابة المرتفع لفايروس النوروكان من شهر كانون الثاني الى اذار والتي كانت بنسبة 81%من الحالات الموجبة ، اما بالنسبة لفايروسالغدينمط 40 / 41كان معدل الاصابة المرتفع من شهر كانون الثاني الى نيسان والتي كانت بنسبة 89.2% من الحالات الموجبة. كما اظهرت النتائج وجود ارتفاع كبيرفيالحركيات الخلويه (السايتوكينات) لمصل الاطفال المصابين مقارنة مع السيطرة. وفقا للفئات العمرية ،اظهرت الفئة( 49 - 60) شهر ارتفاع عالي في مستويات الانترفيرون كاما ، الانترلوكين - 6((IL - 6 والانترلوكين - 12 (12 IL - (حيث كانت للفايروس النورو(90.8, 56.7, 84.3) جزء من الغرام /مل على التوالي،بينما كانت لفايروسالغدي(106.5, 59, 87.5)جزء من الغرام /ملعلى التوالي مقارنة مع مجموعة السيطرة. | Norovirus and adenovirus types (40 and 41) are the important causes of gastroenteritis infections in children worldwide. The present study was designed to determine the incidence and nature of infection of norovirus and adenovirus types (40 and 41) at molecular and immunological levels, as well as some features such as seasonal variation , age distributions and detected the most effective and suitable method for diagnosis of the two viruses . The study was carried out in Al - Najaf province, in AL - Zahra teaching hospital for maternity and children, during the period from January, 2014 to December, 2014. Stool and blood samples were collected from 314 children with diarrhea, their age range (from 1months to 5 years). Immunochromatographic assay for norovirus and adenovirus used to detect their antigens in stool samples, the positive results were confirmed by reverse transcriptase real time PCR technique for norovirus and polymerase chain reaction technique for adenovirus types (40 and 41), which showed incidence of 11.7% and 8.9% for norovirus and adenovirus, respectively. Transmission electron microscopy examination gave clear positive norovirus and adenovirus types (40 and 41) appearance in diarrheal stool samples .The study indicates that molecular methods are most suitable and sufficient tests for routine diagnosis of norovirus and adenovirus types (40 and 41) as compared to transmission electron microscopy analysis for diarrheal samples. According to age groups, the results showed that the majority of infections with norovirus and adenovirus were recorded among age group (13 - 24) months. The positive cases were highly among infants fed with bottle fed (31 cases) compared with infants fed with breast fed (14 cases). Regarding the clinical features of children with viral diarrheal infections , the results showed that all of the cases of both viruses complained of watery or mucosal consistence stool (100%) followed by abdominal pain (94.5%) and (82.1%), vomiting (81%) and (78.5%) , and fever (78.3%) and (71.4%) for norovirus and adenovirus positive children respectively. The present study also revealed that a higher incidence of norovirus was detected from January - March 2014, when it was found in 81% (30/37) of the positive cases, whereas the incidence of adenovirus was higher from January - April 2014, during which it was found in 89.2% (25/28) of the positive cases. The current study for cytokines profile detection showed that significant elevation in patients with norovirus and adenovirus than control. The age groups 49 - 60 months have shown a high level in cytokines Interferon gamma, Interleukin - 6 and Interleukin - 12 with concentration were (84.3, 56.7, 90.8) pg./ml , respectively for norovirus while adenovirus were (87.5, 59, 106.5) pg./ml , respectively as compared with control group . Conclusion of the study shows incidence norovirus genotypeII (GII) and adenovirus types (40 and 41) by rapid chromatographic test from infected children in Al - Najaf province. The study indicates that molecular techniques are most suitable and sufficient tests alternatively for transmission electron microscopy when there is good facility and both can replaced by rapid chromatographic test . Interferon gamma, Interleukin - 6 and Interleukin - 12 were increased in all patients with norovirus and adenovirus infections and showed high level in age group (49 - 60) months
الصفحات الاولى:
مكان الجامعة: النجف
اللغة: الانكليزية
الجامعة: جامعة الكوفة - كلية العلوم - قسم علوم الحياة
الدرجة: دكتوراه
الموضوع الدقيق: علوم الحياة
السنة: 2015
الموضوع العام: علوم الحياة
اسم المشرف: مهدي حسين محيل العمار
اسم المؤلف: رمله احمد محمد حسن العميدي

تنفيذ البوابة اكس اور بصريا بالكامل لمنظومات الاتصالات البصرية Implementation of All Optical Exclusive - OR Gate for Optical Communication Systems

المستخلص: One of the most important techniques used to realize logic gates in optical networks is by all - optical signal processing.The most two important problems of electronic signal processing are high propagation loss of electronic signals and the high cost of the high speed electronics. Accordingly, these reasons led to converting to optical domain at higher frequencies (≥ 10 ????????/????) .The goal of this work is to implement all optical logic gates specifically exclusive - OR gate. Exclusive - OR gate have an important role in data encryption, parity checking, data encoding, bit pattern generation and matching, addressing, header recognition and many more applications. In this work an all - optical exclusive - OR logic function was achieved by a simulation software and implementing an experiment.In the simulation work, the exclusive - OR function was implemental by using a highly nonlinear fiber with a fiber nonlinear coefficient of 9.1 ????−1????????−1 , 0.135 km length non - degenerate with four wave mixing process and a NRZ - DPSK 10 GB/s signals.Experimentally the exclusive - OR function was implemented by using a highly non fiber with a fiber nonlinear coefficient of 10 ????−1????????−1and a 1 km length with bidirectional degenerate four wave mixing process. The optical signals that were used for the operation of the exclusive - OR function were NRZ - DPSK 40 GB/s signals. Results showed an exclusive - OR function associated with clear eye diagrams. In addition to that, exclusive - NOR function was also obtained experimentally in addition of these four maxterms (A + B, ????̅+ B, A + ???? ̅ and ????̅ +???? ̅ ).
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: جامعة بغداد - معهد الليزر للدراسات العليا
الدرجة: ماجستير
الموضوع الدقيق: تطبيقات الليزر في هندسة الالكترونيك والاتصالات
السنة: 2015
الموضوع العام: علوم الليزر
اسم المؤلف: ياسمين سلمان كاظم

تاثير ليزر النودميوم ياك وبيبتيدات الفوسفات الجبنية - فوسفات الكالسيوم الغير متبلرة مع الفلوريد على ازالة تمعدن مينا الاسنان في دراسة مختبرية The Effect of Nd : YAG Laser and Casein - Phosphor - Peptide - Amorphous Calcium Phosphate with Fluoride on Dental Enamel De - mineralization : In vitro study

المستخلص: New approaches for caries prevention by using lasers effect combined remineralizing agent providing calcium and phosphate in addition to flouride for increasing the tooth mineral resistance needed. The aim of this study is to evaluate a new treatment modality to decrease dental enamel dissolution via combing the effect of pulsed Nd : YAG laser (1064 nm) and MI plus paste (CPP - ACP containing sodium fluoride ) regarding the tooth pulp chamber temperature elevation, calcium concentration dissolute from enamel surfaces and the dental enamel absorption of methylene blue stain by assessing (R,G,B)values .Eighty human permanent premolar were used in this study, sixty of them were randomly divided into six groups of 10 specimens. The negative control group A received no treatment, and the positive control group B the MI plus paste was applied without laser irradiation. For the groups C, D, E and F the pulsed Nd : YAG (1064 nm) laser was used in two energy settings. The lower laser dose setting at (0.6W, 60 mJ )without and with the MI plus paste for the groups C and D respectively and the higher laser energy setting at (1.7W, 170 mJ )with and without the MI plus paste for the groups E and F respectively.Twenty teeth were used to asses s the temperature elevation during irradiation with laser using a K - type thermocouple at 37 ± 0.5 ̊C, ten teeth exposed to the lower laser energy settings and ten for the higher laser energy settings.A circular window (4 mm radius) marked area on buccal surfaces of the 60 samples after they had been coated with three layer of nail varnish to exposed to the Nd : YAG laser irradiation, and then the samples incubated in 3ml acidic solution of acetate buffer of (0.1M/L) with a pH value of 4.5 for 48 hours . The acidly etched samples removed from the acidic solution after they had been washed from acid they immersed in a 2% solution of methylene blue dye to measure the (R,G,B) values to indicted the affinity of sample surfaces for absorbing methylene blue stain that indicate the surface demineralization . Results of temperature test +showed that the maximum temperature increases for group E (4.7 Co) was very high significant difference (p<0.05) over that of groups C (2.5 Co).The atomic absorption photometry test results showed that groups C, and D were statistically different compared to the groups A and B (p<0.001) in the reduction of calcium dissolution, with a reduction percentage for groups C and D of 25.7% and 33.34% respectively compared to group A, with 21.75% and 29.8 % for groups C and D respectively in comparison to group B. While Groups E and F shown nonsignificant reduction in calcium dissolution compared to control groups.The (R,G,B)s value test showed that groups C and D having lower affinity to absorb methylene blue stain, and they are statically significant different compared to the groups A and B .while groups E and F showing a higher affinity to absorb methylene blue stain compared to control groups. In conclusion the both laser irradiation settings energy (60mJ, 0.6 W,0.12 J/cm2),(170mJ,1.7W,0.34J/cm2) are safe for the vitality of the dental pulp, and when both settings combined with the Phosphor - Peptide - Amorphous Calcium Phosphate with Fluoride ,the results showing significant reduction of dental enamel de - mineralization and lower affinity for methylene blue absorption that although indicate increasing dental enamel resistance to demineralization for the groups of (60mJ, 0.6 W,0.12 J/cm2) laser irradiation settings.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: جامعة بغداد - معهد الليزر للدراسات العليا
الدرجة: ماجستير
الموضوع الدقيق: تطبيقات الليزر في الطب - طب الاسنان
السنة: 2015
الموضوع العام: علوم الليزر
اسم المشرف: علي شكر محمود
اسم المؤلف: هبة عصام عبد الوهاب

تاثير المعلمات المختلفة لليزر الليف على تعرية الصبغ البوليمري من على سطح سبيكة الالمنيوم نوع 5005A Effect of Different Fiber Laser Parameters on Stripping of Polymer Paint from Surface of 5005A Aluminum Alloy

المستخلص: This study provides details of the use of laser as an alternative method to the conventional ones to remove (20) μm thickness of polyester paint from EN AW - 5005A Aluminum alloy, the laser paint stripping process performed by ytterbium fiber laser with a wavelength (1064) nm .Sets of experiments curried out in order to reach to the most suitable parameters for the process, at the first set different levels of energies used from 0.0425 mJ to 1.12 mJ, nine lines of holes accomplished by laser. The holes diameters and the depth at each energy measured in this experiment. At two different pulse repetition rates (20, 50) KHz two sets of experiments done. At the first set the effect of laser energy (0.1565, 0.73, 1.12)mJ also the overlap percent (25%, 50%, 75%) have been studied at five number of passes, the parameters of the process settled by the overlap equations, the effect of the overlap percent on the total time of machining and the material removal rate at different levels of energy also investigated, it’s found that the best energy to work with is 0.1565mJ with one and two passes.The second set of experiments done at 0.1565mJ with a wider range of overlap percent from 25% to 75% increase by five. The removal depth and the behavior of surface roughness determined by Focus Variation Microscopy (FVM) also Scanning Electron Microscope used to analyze the radiated area. It’s found that the best results obtained at 50 % overlap when the laser passes one time on the material.Laser Induced Breakdown Spectrometer (LIBS) used as a method for monitoring and controlling the paint stripping process in order to accomplish the process and ablate only the paint layer without ablating the substrate, for the paint and the substrate (LIBS) spectrum obtained and used to distinguish between the paint layer and the Aluminum substrate.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: جامعة بغداد - معهد الليزر للدراسات العليا
الدرجة: ماجستير
الموضوع الدقيق: تطبيقات الليزر في هندسة الميكانيك
السنة: 2015
الموضوع العام: علوم الليزر
اسم المؤلف: هالة عبود جاسم

قياس وتحليل الخسائر لموجات الموجع ذوات الفتحة المصنعة من سليكون على عازل Measurements and Analysis of The Losses for Fabricated SOI Slot Waveguides

المستخلص: An interesting silicon photonics component is the slot waveguide. The discontinuity of the normal component of the displacement vector can be used to affect guiding of the majority of the electric field energy in a narrow low index gap when the field is polarized parallel to the silicon surface, that is, perpendicular to the silicon confining walls. By infiltrating nonlinear material into such a gap, one can simultaneously confine electric and optical fields achieving a high efficient optical modulation or switching that is becoming more desirable on optical communication. An array of 200 Silicon - on - Insulator (SOI) slot waveguide devices of varying slot widths, ribs widths, taper lengths and slot lengths are fabricated in each cell of a wafer fabricated at a commercial foundry. The cells are cleaved into individual chips after fabrication. Some chips are coated with thin films of polymers that fully infiltrated the slots. Measurements that consisted on spectral loss are made on the grating coupler waveguide devices of both coated and uncoated chips. Individual devices exhibited insertion losses varying from several dB up to values so great that the response is below the noise floor of the optical spectrum analyzer employed as a receiver. The chips that failed in the transmission test are primarily uncoated ones. Nominally identical devices on different chips exhibited nominally identical behavior. A commercial software program is used to simulate each of the structures that is included in the 200 devices test. The simulations are seen to show a degree of qualitative agreement with the experimental results. Comparison of the experimental measurements and the simulation results indicates that the loss inherent in a slot waveguide is quite low. Near loss free couplers from ridges to slots are achievable in case of coated devices, whereas the situation is different in case of uncoateddevices where a lot of energy is dissipated through the substrate. Use of a surface roughness model indicates that the excess loss that slots exhibit with respect to a ridge mode counterpart arise almost solely from surface scattering off the surface roughness. The increased loss in the case of the slot guide arises from the higher electromagnetic energy density at the surface of the guide due to the electric field discontinuity that is employed as a guidance mechanism in slot modes in contradistinction to ridge modes that are index - guided. Conclusions include some speculation as to the limits on the loss that can be achieved by variation the design of slot guides without any improvement in surface roughness over what is now available with fabrication in commercial foundries.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: جامعة بغداد - معهد الليزر للدراسات العليا
الدرجة: دكتوراه
الموضوع الدقيق: تطبيقات الليزر في هندسة الالكترونيك والاتصالات
السنة: 2015
الموضوع العام: علوم الليزر
اسم المشرف: مازن مانوئيل الياس
اسم المؤلف: ميثم نعيم صالح

محزز الليف البصري نوع براغ لتحسس الحرارة والضغط FIBER BRAGG GRATING FOR TEMPERATURE AND PRESSURE SENSING

المستخلص: Nowadays, the modern trends in optical sensing are to build simultaneous measurements sensors. In this work two schemes for simultaneous measurements sensors are presented. The first one is with dual FBGs peaks. Every FBG acts as sensing head. The first peak was used for temperature sensing and the obtained sensitivity is 10 pm/˚C and the second peak was used for temperature and pressure measurements with sensitivities 9.2 pm/˚C and 67 pm/ bar for temperature and pressure respectively.The other scheme consists of two sensing heads fabricated in the lab. The first sensing head is the Fabry - Perot interferometer which was used for load and strain measurements by controlling the size of its cavity reached to minimum value in micro scale (30). The sensitivity was increased to 4.07 nm/ N and 5.11 pm/ μɛ for load and strain respectively. This sensitivity for load is the highest that was recorded by micro cavity where previous works were reached to 1.37 nm/N. The second sensing head made by inscribing Bragg gratings inside the core of All Solid Photonic Band - Gap fiber toenhance its sensitivity that reached to 13.7 pm/˚C and 0.7 pm/μɛ for temperature and strain respectively which is more sensitive than previous works of our group in the institute that reached to 10 pm/˚C and 0.66 pm/μɛ for temperature and strain respectively. The obtained temperature sensitivity for the Bragg gratings is higher than previous work for Bragg gratings inscribed on All Solid Photonic Band - Gap Fiber where it was 12.04 pm/˚C.Strain sensitivities were almost the same.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: جامعة بغداد - معهد الليزر للدراسات العليا
الدرجة: ماجستير
الموضوع الدقيق: تطبيقات الليزر في هندسة الالكترونيك والاتصالات
السنة: 2015
الموضوع العام: علوم الليزر
اسم المشرف: تحرير صفاء منصور
اسم المؤلف: فهد محمد عبد الحسين

التحقق عمليا من بروتوكول البينغ بونغ

المستخلص: Quantum cryptography uses basic laws of quantum physics to guarantee secure key exchange. The key can be used with unprecedented confidence in any classic cryptographic protocol, where it increases the security to the maximum achievable value. The goal of this work is to encrypt the message directly without need to generate the secure key by using the modified Ping - Pong Protocol. A quantum cryptography system based on Modified Ping - Pong Protocol was designed and implemented for the first time. A polarization - entangled photons were generated by a source using PPKTP crystal inside a polarization Sagnac interferometer at telecom wavelength 1550 nm and a fiber length of 15 Km. In this experiment, Bob prepares entangled photons, sends one photon to Alice by optical fiber to perform one out of four operators according to the message. The modulated photon is sent back to Bob. Then the Bell’s state measurement is applied to extract the message according to the Alice’s coding. The HOM - dip of the two - photon interference was verified to guarantee perfect system performance. The final results showed the switching between the Bell’s states, |????+⟩ and |????−⟩ as the phase of the phase modulator was changed by Alice achieving an acceptable coincidence count of about 625 counts per 30s. These results proves also two photon interference needed to test Bell’s enquality.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: جامعة بغداد - معهد الليزر للدراسات العليا
الدرجة: ماجستير
الموضوع الدقيق: تطبيقات الليزر في هندسة الالكترونيك والاتصالات
السنة: 2015
الموضوع العام: علوم الليزر
اسم المشرف: شيلان خسرو توفيق
اسم المؤلف: علاء جبار جمعة

تحسين خصائص سطح سبيكة الالمنيوم باستخدام الاكساء بالليزر بانابيب كاربون نانوية مزدوجة الجدار ونابيب كاربون نانوية متعددة الجدار Enhancement of Al 6061 - T6 Alloy Surface Properties using Laser Cladding with DWCNTs and MWCNTs

المستخلص: Industrial applications of nanomaterial in particular carbon nanotubes (CNTs) have increased from various viewpoints, such as, high performance, energy saving, cost saving, and environmental concerns. Laser cladding technique has been used successfully to modify the surface properties of materials, i.e., improving their wear and corrosion resistance. This work involves cladding aluminum alloy (Al 6061 T6) with different types of carbon nanotubes (multi - walled carbon nanotubes (MWCNTs) and double walledcarbon nanotubes (DWCNTs)) by an automated pulsed Nd : YAG laser. This was achieved by controlling selected cladding parameters whic h are laser power, pulse duration, and working frequency. The experimental investigation included microhardness, energy dispersive X - ray, corrosion resistance and microstructure topography by scanning electron microscope. At the beginning, fifteen cladded samples divided into three groups were investigated to choose the best laserparameters for the process to have almost the best homogeneous clad layer. Group one; five levels of peak power (2.7, 2.9, 3.1, 3.3, and 3.5) kW respectively where varied versus fixed pulse duration of 16 ms, working frequency of 1.5 Hz, and scanning speed of 0.5mm/s. Group two; five levels of pulse duration (12, 14, 16, 18 and 20) ms respectively where varied versus fixed peak power of 3.1 kW, working frequency of 1.5Hz, and scanning speed of 0.5mm/s. Group three; five levels of working frequency of (1.1, 1.3, 1.5, 1.7, and 1.9) Hz respectively where varied versus fixed peak power of 3.1 kW, pulse duration of 16 ms and scanning speed of 0.5 mm/s. The investigation shows that the optimum estimated laser parameters for achieving the best results at spot diameter of 3 mm were (peak power of 3.1 kW, pulse duration of 16 ms (3 ms as preheating and 13 ms as the main action time of the pulse) and working frequency of 1.5 Hz.The executed process in this work was computationally modeled using commercial multiphysics finite element analysis (FEA) software package ANSYS® Release 11 to simulating the virtual environment of laser cladding process to determine the temperature distribution in three - dimensional (3D) analysis. Results indicated that laser cladding of Al 6061 T6 using DWCNTs enhanced three of the most important of surface properties which are hardness, abrasive wear resistance and corrosion resistance more than did the MWCNTs. The distribution of the MWCNTs on the surface of Al 6061 T6 is better than that for the DWCNTs but its penetration is less. Theoretical results show that the diffusion played an important role in the cladding process.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: جامعة بغداد - معهد الليزر للدراسات العليا
الدرجة: ماجستير
الموضوع الدقيق: تطبيقات الليزر في هندسة الميكانيك
السنة: 2014
الموضوع العام: علوم الليزر
اسم المؤلف: حسنين مجيد حسين

الليف البلوري الفوتوني لاستشعار المجال المغناطيسي Photonic crystal fiber magnetic sensor

المستخلص: Photonic crystal fiber (PCF) is widely used for sensing applications. In this work, magnetic sensor based on solid core - PCFs for sensing magnetic field was presented. The general structure of the sensor applied is by splicing short lengths of PCF (LMA - 10) with conventional single mode fiber (SMF - 28) in one side and using free space connector from other side. A laser diode with different wavelengths (850, 1060 and 1300 nm) has been used as a light source, where a high sensitive optical spectrum analyzer (OSA) was used to monitor and record the transmitted/reflected spectra.The present work demonstrates the results of the infiltration of the air holes for the PCFs by fluids instead of air. For magnetic sensing, the magnetic fluids being used were prepared and standard ????????3????4 to infiltrate the air holes for the solid core PCF (LMA - 10) which leads to change in the effective refractive index of the PCF, which in turn affects the transmission of the laser inside the PCF due to the value of the refractive indices of the magnetic fluids. The experiments show that the power of transmissionspectrum of the laser had decreased after infiltration without any change in central wavelength of the laser diode the reason is that after PCF air holes infiltration, the effective refractive index has been changed but still within total internal reflectionwhich leads to loss of some fundamental modes, in turn leads to decrease the power of transmission spectrum. The decrease of the transmitted power in the case of standard has been higher than it in the case of prepared ????????3????4 because of the differencein concentration between standard and prepared magnetic fluids. The power of transmission spectrum after PCF infiltration will be increased with increasing magnetic field. Higher sensitivity has been obtained that reached 5.809 nW/mT which consideredhigher than previously published works on PCF magnetic sensors.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: جامعة بغداد - معهد الليزر للدراسات العليا
الدرجة: ماجستير
الموضوع الدقيق: تطبيقات الليزر في هندسة الالكترونيك والاتصالات
السنة: 2015
الموضوع العام: علوم الليزر
اسم المشرف: عبد الهادي مطشر الجنابي
اسم المؤلف: احمد عدنان محمد

التحقق من تاثير عدم استقرارية بلاتو - رايلي في عملية سحب ليف شبه المواد انديوم - بوليمر Investigation of the influence of the Plateau - Rayleigh instability in fibre drawn indium - PMMA metamaterial

المستخلص: Metamaterial is a synthetic composite material with a structure such that it exhibits properties not usually found in natural materials. Fibre drawing method has been used in producing Poly - methyl methacrylate (PMMA) - indium wires metamaterials. PMMA and indium are having relatively the same glass transition temperature making them suitable for co - drawing. The fiber filaments must be drawn to smaller diameters to shift the metamaterials response to higher frequency. At these dimensions the metal filaments inside the fiber become unstable and break - up at random intervals. This instability is due to a phenomenon known as the Plateau - Rayleigh InstabilityWell known Tomotika model for the growth in the varicosity in the surface of fluid extended inside another fluid was modified to describe the fluctuations (instability) of inner core diameter for metamaterials drawing inside radiative furnace. Modified Tomotika model was used to investigate the instability growth of the indium wire diameter produced by co - drawing of indium metal embedded in a PMMA polymer.The critical parameter for the wire breaks is the wavelength of perturbations. A MATLAB model was used to describe a small drawing ratio (neglecting the wavelength of fluctuations effect). The experimental and modeling results are almost match when a very small temperature variation occurred. So the observed fluctuations in diameter can be reconciled with the Plateau - Rayleigh instability.For larger fluctuations (large drawing ratio) the wavelength of fluctuations was analyzed and sequential breakup on different length scales was observed. We infer limits to wire dimensions that can beachieved using the chosen material system and identify a path for extending drawing methods to fabricate smaller wires.Finally, simulation for deep subwavelength wave propagation inside wire metamaterials depending on the unit cell manipulation was performed. CST microwave studio software had been used to simulate wave propagation inside linear and 90o corner waveguide as well as equal arms beam splitter (50/50). It’s applicable to waveguiding 40cm wavelength in about 2.4 cm waveguide.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: جامعة بغداد - معهد الليزر للدراسات العليا
الدرجة: دكتوراه
الموضوع الدقيق: تطبيقات الليزر في هندسة الالكترونيك والاتصالات
السنة: 2015
الموضوع العام: علوم الليزر
اسم المشرف: عبد الهادي مطشر الجنابي
اسم المؤلف: احمد عبد الكريم علي

التلوين المستحث بليزر الليف للتيتانيوم العالي النقاء Fiber Laser Induced Colouration of High Purity Titanium

الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: جامعة بغداد - معهد الليزر للدراسات العليا
الدرجة: ماجستير
الموضوع الدقيق: تطبيقات الليزر في هندسة الميكانيك
السنة: 2015
الموضوع العام: علوم الليزر
اسم المؤلف: نور ياسر حسون حمادي

التقييم السريري لالتام الانسجة للمابس السنية المنزوعة المشععة بليز الدايود 940 نانومتر Clinical Assessment of The Tissue Healing of Extraction Socket Irradiated with 940 nm Diode Laser

الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: جامعة بغداد - معهد الليزر للدراسات العليا
الدرجة: ماجستير
الموضوع الدقيق: تطبيقات الليزر في الطب - طب الاسنان
السنة: 2015
الموضوع العام: علوم الليزر
اسم المشرف: علي شكر محمود
اسم المؤلف: ندى حسين حمودي

دراسة تجريبية للحيود الحراري في صبغات مختلفة Experimental Study of Thermal Self - Defocusing in Different Dyes

المستخلص: This thesis discusses the effect of three factors on self defocusing technique used to measure the nonlinear optical properties of two solutions, the first one is safranin O dissolved in ethanol (SOE), and the second one is diphenylecarbazone dissolved in chloroform (DCC). These factors are the intensity of laser, the concentration of the solution and the effect of the temperature on the solutions.After providing the necessary solution and equipment to complete the designed experiment, an appropriate model of nonlinear system was chosen to extract the diffraction rings contains the following parts : (Diode Laser, Attenuator, Mirrors, Beam Splitter, Lens, CCD Camera, Laser Power Meter and PC) In this work the maximum change and the thermo - optical coefficient for the nonlinear refractive index as well as the nonlinear refractive index were measured, for the two different solutions (SOE & DCC) including three ratios and grains for each one. The measurements were performed using diode laser at and variable intensity (0.5 - 22) and the laser beam was focused on glass cuvette which has a thickness of through a lens with a focal length of .From this work it was found that increasing the laser intensity leads to increase the number of diffraction rings, the nonlinear refractive index and the maximum change of the nonlinear refractive index, also it was found that increasing the concentration of the solutions leads to increase the nonlinear refractive index as well as increasing the maximum change of the refractive index.Also it was found that increasing the temperature of the solution at certain intensity and concentration the obtained results for the thermooptical coefficient , and the nonlinear refractive index are found to be of the order of and at 298, 303 and 308K respectively for SOE solution, and and at 298, 303 and 308K respectively for DCC solution, in which all the thermooptical coefficient and the nonlinear refractive index are deceased.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: جامعة بغداد - معهد الليزر للدراسات العليا
الدرجة: دكتوراه
الموضوع الدقيق: تطبيقات الليزر في الفيزياء
السنة: 2013
الموضوع العام: علوم الليزر
اسم المشرف: مازن مانوئيل الياس
اسم المؤلف: عمار محمد طعيمة

لحام ليزر الاندي ياك لمعادن غير متشابهة تيتانيوم رتبة 2 مع سبيكة المنيوم - O3105 Dissimilar Nd : YAG Laser Welding of Grade 2 Titanium to 3105 - O Aluminum Alloy

المستخلص: التيتانيوم والالمنيوم مواد تلقى اهتمام تقني في الصناعات الالية والفضائية والمتحسس الذكي.التحديات التي تواجه لحامهم هي نتيجة للاختلاف الكبير في المواصفات الثرموفيزيائية والميكانيكية, اضافة الى الذوبانية المحدودة لكل معدن في الاخر,لذلك لحامهم باستعمال الليزرسيقلل تكوين الا طوار المعدنية الضارة لما كانت منطقة اللحام نفسها ضيقة .في هذا العمل قدم شكل خاص من اللحام الليزري النقطي لربط تيتانيوم رتبة 2 تراكبيا مع سبيكة المنيوم 3105 - O باسماك 1,0.5 ملم على التوالي, من خلال لحام درز دائري, لبق التصميم يستعمل نبضات ليزر متعاقبة ادت الى لحام شبيه للحام الليزري النقطي .لهذه الدراسة كانت معاملات لحام الليزر كالاتي : طاقة النبضة 11جول, مدة النبضة 6 ملي ثانية, تردد النبض 20هرتز,تدفق غاز الاركون 20 لتر/دقيقة وسرعة اللحام (4 - 6.67) ملم/ثانية.لقد لوحظ ان تاثيرسرعة اللحام كان الاقوى على الحرارة الداخلة لمنطقة اللحام حيث سرعة لحام 4 ملم /ثا (76%عامل تداخل النبضات), قد ادت الى افضل امتصاص لطاقة الليزر واكثر تجانس وعرض للمساحة المنصهرة عند منطقة تداخل ,Ti - Alلذلك تم الحصول على 70MPa مقاومة وصلة اللحام. اظهر فحص منطقة وصلة اللحام باستخدام المجهر الماسح الالكتروني SEM, مقياس تشتت طاقة الاشعة السينية EDS ومقياس انحراف الاشعة السينية,XRD تكون الا طوار المعدنية الضارة. المنطقة المنصهرة للتيتانيوم قرب منطقة تداخل Ti - Alضمت طور.Ti3Al الشقوق لوحظت في منطقة الالمنيوم المنصهرة قرب منطقة التداخل ,Ti - Alنتيجة الانحدار العالي في الخواص الميكانيكية والثرموفيزيائية. من اجل التقليل من تكون الا طوار المعدنية الضارة وتخفيف الانحدار العالي في الخواص . الثرموفيزيائية والميكانيكية, اربعة انواع مختلفة من الحشوات المعدنية (Al - 5Si, Al - 12Si - 2.5Mg, pure Nb and Al - 0.2Sc - 0.36Zr) مع ثلاثة اسماك مختلفة لكل حشوة قد حضرت في هذا العمل. حشوة Al - 5Si كان لها تاثير ايجابي على مقاومة وصلة اللحام حيث ان Siقلل التاثير الضار للاطوار المعدنية الضارة من خلال تعويض ذرات Al في Ti3Al لذلك فان مقاومة الوصلةزادت الى MPa80بدل MPa70.حشوة Al - 12Si - 2.5Mg قد حسنت مقاومة الوصلة الىMPa87 متجاوزة بذلك مقاومة القصMPa82 لترابط المعدن الاساس Al. نتيجة درجة اانصهاره العالية, حشوة النيبيوم النقي Nb منعت لحام صفيحة Al السفلى, لذلك هذه الحشوة كانت غيرمناسبة للا ستعمال وفق شروط اللحام لهذا العمل. لقد كان للحشوة الجديدة Al - 0.2Sc - 0.36Zr التي استعملت لاول مرة من خلال هذا العمل تاثير ايجابي جدا على قوة ترابط وصلة اللحام MPa103 حيث ان الكسر حدث من المعدن الاساس Al وليس من الوصلةخلال عملية الاختبار. بالمقارنة مع مقاومة التاكل لمعدن التيتانيوم الاساس, اظهرت الوصلات بدون استعمال حشوة وباستعمال حشوة Al - 0.2Sc - 0.36Zr نقصان بمعدل التاكل ب %51 و%72 بالتعاقب بينما اظهرت الوصلات باستعمال حشوات Al - 5Si,Al - 12Si - 2.5Mg زيادة بمعدل التاكل ب % 80 و%68 بالتعاقب. | Materials titanium and aluminum are of technological interest in automotive, aerospace and smart sensor industries. The challenges for welding them result from the large difference in thermophysical and mechanical properties, besides limited solubility of each metal in other. Thus welding them using laser, will reduce intermetallic phases (IMP) formation to acceptable limits, since the weld itself is narrow.In the present work a special form of laser spot welding is introduced to joint overlapped titanium Ti Grade 2 to 3105 - O aluminum alloy, with 1 and 0.5 mm thicknesses respectively. A welding tactile seam tracking design using following pulses that result to a circular seam, leads to spot like shape laser welding. For this study, laser welding parameters were : pulse energy 11 J; pulse duration 6ms; pulse frequency 20Hz; argon gas flow rate 20 l/m and welding speed (4 - 6.7) mm/s. Welding speed was observed to have the strongest effect on heat input, where 4 mm/s (76% overlapping) speed has led to better energy absorption and wider more uniform melted area at Ti - Al interface, thus 70 MPa joint strength was obtained. Examination of the joint region using scanning electron microscopy (SEM), energy dispersive X - ray spectrometry (EDS) and X - ray diffraction (XRD) showed the formation of different IMP in the Ti - Al welding zone. Ti fusion zone (FZ) near the interface was mainly containing Ti3Al. Crakes were observed in Al (FZ) near the interface as a result of mechanical and thermo physical properties gradient. Inorder to reduce IMP formation and relaxes the high gradient in thermophysical and mechanical properties in the welding zone, four fillers metals (Al - 5Si, Al - 12Si - 2.5Mg, pure Nb and Al - 0.2Sc - 0.36Zr), with three different thicknesses for each filler, were prepared. Al - 5Si filler has positive effect on the joint strength where Si has reduced the IMP harmful effect via replacing Al atoms substitutionaly in TiAl3 at the interface, thus joint strength was increased to 80MPa instead of 70MPa. Al - 12Si - 2.5Mg filler has improved the joint strength to 87MPa where the shear strength of Al base metal of 82MPa was exceeded. Due to its high melting point pure Nb filler prevented penetration of bottom Al sheet, thus it was unsuitable to use for the present work conditions. A new Al - 0.2Sc - 0.36Zr filler was used for the first time in the present work and has very positive impact to the joint strength 103MPa, where the joint has fractured from Al base metal. In comparison to the corrosion rate of Ti base metal, joints without using filler and with the new Al - 0.2Sc - 0.36Zr filler metal, have decreased the corrosion rate by 51% and 72% respectively, while joints with Al - 5Si and Al - 12Si - 2.5Mg filler metals, have increased the corrosion rate by 68% and 80% respectively.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: جامعة بغداد - معهد الليزر للدراسات العليا
الدرجة: دكتوراه
الموضوع الدقيق: تطبيقات الليزر في هندسة الميكانيك
السنة: 2015
الموضوع العام: علوم الليزر
اسم المؤلف: عبير احمد شهاب العبيدي

الكشف عن البخار الكيميائي بحساسية عالية المستند على مقياس التداخل لليف البلوري الفوتوني Chemical vapor detection with high sensitivity based on Photonic crystal fiber interferometer

المستخلص: استخدمت مقاييس تداخلات الالياف البلورية الفوتونية في العديد من تطبيقات التحسس. في هذا البحث, تم استخدام الالياف البلورية الفوتونية ذو القلب الصلب المستندة على مقياس تداخل ماخزندر, الذي يسلك حساسية عالية لمعامل الانكسار ومختلف المركبات العضوية المتطايرة، من دون الحاجة الى اي مواد قابلة للاختراق. مقياس التداخل المدمجة ,القوية ويتكون من نهاية ليف بصري بلوري ,الليف البصري البلوري مرتبط مع الليف التقليدية ذات النمط المنفرد ((SMF - 28هذا الارتباط يكون باقل خسارة dB(0.19) في منطقة الارتباط فتحات فراغات الليف تنهار كليا, وتسمح بلتهيج واعادة التركيب للانماط القلب والغلاف .وفي منطقة الارتباط الانماط الاساسية لليف البصري التقليدي تبدا بالحيود عندما تدخل الجزء المنهار من منطقة الارتباط لليف البلوري الفوتوني . بسبب الحيود ، يوسع النمط ويسمح لاثارة نمطين رئيسيين في نهاية اليف البصري الفوتوني.الجهاز يعكس الطيف ويظهر نمط تداخل كدالة جيبية التي تظهر ازاحة بالطيف البصري بشكل مختلف عندما تتسل جزيئات المركبات العظوية المتطايرة الى فتحات الليف البصري البلوري. استخدم ليزر دايود كمصدر ضوئي وبطول موجي 1550 nm ، حيث تم استخدام محلل الطيف الضوئي (OSA) الحساس للغاية في رصد وتسجيل الطيف المنعكس. استخدم ثلاثة انواع من السوائل الكيميائية (N - الهكسين، الميثانول وبروبانول)، كل هذه السوائل الكيميائية وابخرتها لها شفافية عالية في منطقة الطيف المرئي والمنطقة تحت الحمراء القريبة. في هذه التجربة، وجدنا افضل زمن الاستجابة لهذا المتحسس هو من (30 - 35) ثانية لكميات قليلة جدا من هذه السوائل، كما تم دراسة تاثير طول المتحسس على قيمة الازاحة للطول الموجي ، تم اختبار خمسة اطوال مختلفة من PCF ذو القلب الصلب70,50,40,30and 20) nm). حدود الكشف في هذا الجهاز تم من خلالها تسجيل ازاحة في الطول الموجي لنسب من ابخرة مواد كيمياوية تصل لغاية (4.4) nm للبخار الهكسان عندما يكون طول رئس المتحسس (20)mm . في هذا العمل, الحد الاقصى للحساسية التي تم الحصول عليها للمركبات العضوية المتطايرة هي mol \15420 nm في بخار الهكسان .وقد تحققت بعض نتائج المحاكاة باستخدم برنامج COMSOL multiphysics ,تم استخدم هذا البرنامج لتصميم الليف البصري البلوري وايجاد توجيه دايود ليزر 1550 nm داخل الليف البصري البلوري عندما يتغير معامل الانكسار نتيجة لدخول ابخرة المركبات العضوية المتطايرة(هكسان, بروبان, وميثان) وملئها لفتحات الليف. نتائج mulyiphsics COMSOL عندما تسلل ابخرة السوائل الى فراغات الليف البلوري الفوتوني بدلا من الهواء. وعندما يتسلل بخار السائل الى PCF ذو النواة الصلبة (LMA - 10) الذي يؤدي الى تغيير في معامل الانكسار الفعال للPCF، والتي بدورها تؤثر على انتقال ليزر داخل PCF بسبب قيمة معاملات الانكسار للمركبات العضوية المتطايرة. ويظهر نتيجة لذلك ان طاقة طيف انتقال الليزر تخفضت بعد تسلل البخار مع التغير في الطول الموجي المركزي لليزر الدايود. | Photonic crystal fiber interferometers are used in many sensing applications. In this work, an in - reflection photonic crystal fiber (PCF) based on Mach - Zehnder (micro - holes collapsing) (MZ) interferometer, which exhibits high sensitivity to different volatile organic compounds (VOCs), without the needing of any permeable material. The interferometer is robust, compact, and consists of a stub photonic crystal fiber of large - mode area, photonic crystal fiber spliced to standard single mode fiber (SMF) (corning - 28), this splicing occurs with optimized splice loss 0.19 dB. In the splice regions the voids of the holey fiber are completely collapsed, which allows the excitation and recombination of core and cladding modes. The device reflection spectrum exhibits a sinusoidal interference pattern which shifts differently when the voids of the PCF are infiltrated with VOC molecules. Laser diode with wavelength 1550nm has been used as a pump light source, where a highly sensitive optical spectrum analyzer (OSA) was used to monitor and record the reflected spectra. Three types of chemical liquids used (N - Hexane, Methanol and Propanol), all of these chemical liquids and their vapor have a high transparency for visible and NIR spectrum. In this experiment, we found the best response time to this sensor is from (30 - 35) sec for very few quantities from these liquids which approximately measured in microliter, also it was studied the effect of the length of the head sensor on the volume of shift of the wave length, five different lengths of solid core PCF (LMA - 10) (70,50,40,30, and 20) mm were tested.The detection limits of our device associated with the maximum shifts of the wave length is 4.4nm for N - Hexane vapour when the length of the head sensor 20mm.In this work, the maximum sensitivity obtained of volatile organic compounds is 15420nm/mol at the vapor of N - Hexane.Some simulation results have been achieved by using the COMSOL mulyiphsics program. It used to design the photonic crystal fiber large - mode area and find the guiding of laser 1550 nm at this fiber when change the refractive index cladding of the photonic crystal fibers by filling the hole of cladding in vapor of (N - Hexane, propanol, methanol) at 1550 nm, The results of the COMSOL mulyiphsics when infiltration of the air holes for the PCF by vapor liquids instead of air, due the change value of the effective refractive indices of the VOCs, the power of the transmission spectrum of laser decreased after infiltration with change in the center wavelength of the laser diode
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: جامعة بغداد - معهد الليزر للدراسات العليا
الدرجة: ماجستير
الموضوع الدقيق: تطبيقات الليزر في الفيزياء
السنة: 2015
الموضوع العام: علوم الليزر
اسم المشرف: حنان جعفر طاهر
اسم المؤلف: رواء كاظم زرزور

التحقق عدديا وعمليا من مبادل حراري ذو سائل نانوي في منظومة التبريد والتهوية والتدفئة مع الكشف بالليزر Numerical and Experimental Investigation of a Nanofluid Heat Pipe Heat Exchanger in HVAC System with Laser Detection

المستخلص: The improvement of energy saving in heat pipe heat exchanger system was investigated .Theoretical work was done to study the effect of coating with nanomaterials on the thermal performance of HPHE to enhance the energy saving. Temperature distribution and thermal resistance for different nano materials (BN, WC, HFB2, MgO and MOSi2), metal and metal oxide (Ag, Cu, AL, BeO, Al2O3 and CuO) on fins were studied. The maximum enhancement of the thermal performance at the evaporator section in steady state operation condition was (5.072, 5.063, 5.075 and 5.069) for (WC, HFB2, MgO and MOSi2) respectively and (5.829) for (BN) at the same section in transient operation condition while at the same section in steady state operation condition (5.063, 5.064, 5.07, 5.068, 5.075 and 5.076) for (Ag, Cu, AL, BeO, Al2O3 and CuO) respectively was detected. The best nano material for enhancement the thermal performance of HPHE are BN for nanomaterial ,Al for nano metal and CuO for nano metal oxide .The thermal performance of seven thicknesses of CuO coating layers on HPHE fins was also studied. Results showed that the enhancement of the thermal performance is decreasing with the increment of coating thickness at the evaporator section of transient conditions (5.076, 5.075, 5.073, 5.072, 5.070, 5.068 and 5.067) for (10, 25, 50, 75, 100,125and150)μm thicknesses respectively. Experimental work was done to examine the general performance of thermosyphon heat pipe at four concentrations (0.05, 0.2, 0.6 and 1) wt. % of nanofluid. Two CW diode lasers (532,650) nm were used as a detection system to determine the variation of the concentration within the system operation. The results showed that fourteen percent reduction in thermal resistance is detected for 0.05wt.% relative to the DI - water . The shorter time of steady state condition of operation, the higher values of total thermal effectiveness, energy saving and energy balance ratio of HPHE were satisfied at 0.05wt.%. The maximum value of relative powers of 0.05wt% nanofluid concentration is detected compared with the other concentrationsdue to the low density of nanofluid concentration. The start sensing and ending detection powers are (0.1, 1) W respectively of this type of nanofluid.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: جامعة بغداد - معهد الليزر للدراسات العليا
الدرجة: دكتوراه
الموضوع الدقيق: تطبيقات الليزر في هندسة الميكانيك
السنة: 2015
الموضوع العام: علوم الليزر
اسم المشرف: حسين علي جواد زينب فاضل مهدي
اسم المؤلف: ايسر عبد الرزاق الاميري

تصنيع مواد متوافقة احيائيا للعظام التعويضية باستخدام الليزر ووسائل تقليدية Fabrication of Biocompatible Material for Bone Implants Using Laser and Conventional Means

المستخلص: The present work describes coating the titanium implants with biocompatible materials (ceramics or composites). Three techniques were implemented to materialize this work; these are : pulsed laser deposition, spray pyrolysis, and electrochemical deposition. In these techniques, the influence of deposition temperature, solution concentration, polymer and H2O2 addition, buffer layer sandwiching, and electrolytes combinations were tested. The obtained films’ properties were investigated by using Fourier Transform Infrared Spectroscopy (FTIR), Atomic Force Microscope (AFM), Optical Microscope, X - ray Diffraction (XRD), Scanning Electron Microscope (SEM), Vickers’ hardness instrument, and Simulated Body Fluid (SBF).Composite films prepared by pulsed laser deposition showed the formation of polycrystalline hydroxyapatite of low crystallinity due to the addition of polymeric shrimp crusts. These films had (80 - 90 nm) spherical grains and constitute only (20 - 25%) of the favorable range (80 - 200 nm), and good hardness (≈550 HV). Pure hydroxyapatite (ceramic) films had (11 - 15 nm) surface roughness and an average grain size of (48 - 65 nm) which represents (7 - 31%) of the favorable range. All these films were porous, have good adhesion, and uniform surface morphology. Best results of pulsed laser deposition technique were obtained at 125oC deposition temperature. Films prepared by spray pyrolysis showed porous polycrystalline A and B - type carbonated hydroxyapatite and single crystalline α - Ca3(PO4)2; of relatively low crystallinity and hardness increased with deposition temperature. Post annealing at 400oC and 800oC for film prepared at 350°C of (0.0325 M) solution concentration has raised the hardness from 222 HV to 488 HV and 1204.25 HV respectively. The films of (0.0325 M) solution concentration had (101 - 105 nm) average grain size and were (78 - 100%) of the favorable range, whereas the films of (0.0406 M) solution concentration had (92 - 96 nm) and made (74 - 100%) of the favorable range. Good bioactivity and adhesion strength were obtained from these films which were enhanced significantly after post annealing. Optimum results were obtained from films prepared at 350oC of (0.0325 M) solution concentration after post annealing. Films prepared by electrochemical deposition technique showed uniform and highly porous polycrystalline B - type carbonated hydroxyapatite and polycrystalline α - Ca3(PO4)2. These films had an average grain size of (66 - 93 nm) when prepared from ((NH4)2HPO4 and Ca(NO3)2) whereas the grain size was (87 - 118 nm) when prepared from (Na3PO4 and Ca(NO3)2) with low roughness values. They had (45 - 68%) and (64 - 87%) respectively of the useful grain size in the favorable range (80 - 200 nm). The films covering area increased after H2O2 addition. These films had poor adhesion but this slightly improved together with the roughness after a buffer layer was deposited.The composite films had low crystallinity, grain size, hardness, and poor adhesion. Films prepared at 70oC from both electrolytes combinations ((NH4)2HPO4 with Ca(NO3)2, and Na3PO4 with Ca(NO3)2) had the best surface morphology and crystallinity with an optimum hardness (≈475HV). All these films had very fast dissolution rate in Simulated Body Fluid. Spray pyrolysis deposition technique proved to be the most promising technique for biocompatible materials fabrication for bone implants requirement
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: الجامعة التكنولوجية
الدرجة: ماجستير
الموضوع الدقيق: تطبيقات الليزر في الفيزياء
السنة: 2014
الموضوع العام: علوم الليزر
اسم المشرف: رائد عبد الوھاب اسماعیل ولید خلف حمودي
اسم المؤلف: هدیل فیاض عباس

فعالية المضاد البكتيري لاكاسيد المعادن النانوية المحضرة بواسطة الاستئصال بالليزر في سائل Antibacterial Activity of Metals Oxide Nanoparticles Induced by Laser Ablation in Liquid

المستخلص: With the increasing of bacterial resistance against antibiotics, nanoparticles studies was appeared together with growing need for substituting theseantimicrobial agents. Recently, it has been demonstrated that metal oxides nanoparticles exhibits bactericidal effect against both bacteria strains.In this research, three kinds of metal oxide nanoparticles (Nickel oxide, Copper oxide and Titanium dioxide) colloidal solutions synthesized using laser ablation of nickel, copper and titanium pellet immersed in de - ionized water. Pulsed Nd : YAG laser with 1٠٦٤ nm wavelength and different laser energies (40, 80, 120, 160 and 200 mJ) was used to irradiate the targets for various ablation times : 5 (75 pulse), 10 (150 pulse), 15 (225 pulse) and 20 min (300 pulse).The UV - Visible absorption spectrum of NiO nanoparticles exhibited broad bands whose intensity decreased continuously above ~210 nm. The UV - Visible absorption spectrum of the CuO nanoparticles solution showed absorption peak around ~275 nm and another peak with low intensity around ~645 nm. While absorption spectrum of TiO2 nanoparticles exhibited strong absorption domination on the spectrum below ~360 nm. In all three metal oxide nanoparticles, absorption intensity increased with the laser energy and ablation time due to increase nanoparticles concentrations in liquid. Fourier Transform Infrared spectroscopy characterization confirmed the formation of metal oxide nanoparticles. All three metal oxides nanoparticles gave absorption bands below ~600 cm−1 arising from inter - atomic vibrations. X - ray Diffraction pattern of nanoparticles proved the presence of (111), (200) planes which belong to NiO and ( - 111), (112) planes that assigned to CuO and (101), (112), ( - 403) planes that related to TiO2. TransmissionElectron Microscopy measurement showed NiO, CuO and TiO2 nanoparticles with nearly spherical shapes and sizes at 2 - 21 nm, 3 - 40 nm and 6 - 30 nm respectively.The antibacterial activity of nanoparticles carried out against four types of bacteria : Escherichia coli, Pseudomonas aeruginosa, and Proteus vulgaris (gramnegative bacteria), Staphylococcus aureus (gram - positive bacteria) firstly by liquid medium method. 1000 μg ml - 1 concentration was the best - used concentration of nanoparticles for inhibiting growth of both bacteria strains. Among the three tested types of nanoparticles (NiO, CuO and TiO2) at highest concentration (1000 μg ml - 1), TiO2 NPs showed the highest antibacterial activity against Escherichia coli and Pseudomonas aeruginosa. NiO NPs showed the highest antibacterial activity against Staphylococcus aureus while CuO NPs showed the highest antibacterial activity against Proteus vulgaris. Results also indicated that metal oxide nanoparticles and amoxicillin would have a synergistic effect on inhibiting of bacterial growth. Amoxicillin showed inhibitory rate about 74.8% against Escherichia coli and 76.28% against Staphylococcus aureus. In the case of NiO, CuO and TiO2 nanoparticles at concentration 1000 μg ml - 1 with Amoxicillin, antibacterial activity of Amoxicillin enhanced to about 81.5%, 90% and 81.9% against Escherichia coli and to about 86.9%, 91% and 90.7% against Staphylococcus aureus. Therefore, CuO nanoparticles and amoxicillin have the best synergic effect on inhibiting both bacteria strains. The antibacterial activity of the three metal oxides nanoparticle combined with Amoxicillin was also tested by well diffusion method against Escherichia coli and Staphylococcus aureus. In this method, CuO NPs at concentration 1000 μg ml - 1 along with Amoxicillin showed the highest inhibition zone against Escherichia coli (26.0±1.00 mm), while showed complete inhibition of bacteria against Staphylococcus aureus.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: الجامعة التكنولوجية
الدرجة: ماجستير
الموضوع الدقيق: تطبيقات الليزر في الفيزياء
السنة: 2014
الموضوع العام: علوم الليزر
اسم المشرف: خولة صلاح خشان غسان محمد سلمان
اسم المؤلف: فرح عبد الكريم عبد الامير

مقاييس النعومة وتقريب الدوال في الفضاءات L - p المعرفة على كرة الوحدة Moduli of Smoothness and Approximation of Functions in L_pSpaces Defined on Unit Sphere

المستخلص: هذه الرسالة هي دراسة لافضل تقريب للدوال في الفضاءات L_p والمعرفة على كرة الوحدة .ان مشكلتنا الاساسية هنا هي وصف عملية التقريب للدوال في الفضاءات L_p عندما 0<p<1 باستخدام متعددات الحدود بدلالة مقياس النعومة للدالة .سنحدد في عملنا الاداة الصحيحة لوصف او دراسة معامل النعومة للدالة في الفضاءات L_p من ناحية معامل النعومة للدالة او الدالي K . سنبرهن فيما بعد ان الاداتين متكافئتين ركزنا في نتائجنا الاساسية على وصف افضل تقريب من خلال المبرهنات المباشرة واخرى معكوسة لها بدلالة ثلاث انواع مختلفة من مقاييسالنعومة وثلاث انواع من الدالي K . | This thesis is a study on best polynomial L_P , approximation on unit sphere . Our central problem is to describe the approximation behavior of functions in L_P - spaces for 0<p<1 by polynomials via higher order modulus of smoothness of function. In this work we identity the correct gadget to characterize smoothness of functions in L_P - spaces in terms of, either modulus of smoothness or K - functional, that are then we prove they are equivalent.In our main results we concentrate on characterization of best approximation , given in terms of direct and inverse theorem in terms of three types of moduli of smoothness and K - functional
الصفحات الاولى:
مكان الجامعة: بابل
اللغة: الانكليزية
الجامعة: جامعة بابل - كلية التربية للعلوم الصرفة - قسم الرياضيات
الدرجة: ماجستير
الموضوع الدقيق: الرياضيات
السنة: 2017
الموضوع العام: علوم الرياضيات
اسم المشرف: ايمان سمير عبد علي بهية
اسم المؤلف: اخلاص عنون موسى

استخدام النموذج الرياضي والشبكات العـصبية لتحديد نسبة تلوث البيئة Employ Mathematical Model and Neural Networks for Determining Rate of the Environmental Contamination

المستخلص: هناك العديد من الاهداف في هذه الرسالة : الهدف الاول هو تطوير نموذج المعادلة التي تصف انتشار التلوث خلال التربة والتي يمكن استخدامها لتحديد نسبة التلوث البيئي وذلك بتقدير تركيز المعادن الثقيلة في التربة. نموذج المعادلة التي تم تطويرها يمكن اعتبارها تمثيل جيد لمشكلة التلوث البيئي.الهدف الثاني في هذه الرسالة هو تصميم شبكتين عصبيتين ذات تغذية تقدمية باعتبارها تقنية دقيقة بديلة لتحديد نسبة التلوث البيئي والتي يمكن استخدامها في حل معادلة النموذج. الشبكة الاولى تحاكي معلمات التربة التي يمكن استخدامها في ادخال البيانات في الشبكة الثانية المقترحة، في حين تحاكي الشبكة الثانية لتقدير تركيز المعادن الثقيلة.الهدف الثالث هو تطوير المفهوم النظري لمرحلة تدريب الشبكات العصبية من وجهة نظر التحليل الدالي والطرق الامثلية. ضمن هذه الصيغة، التعلم يعني حل مشكلة متغايرة بواسطة تصغير دالة الاداء المتعلقة بالشبكة العصبية. ان اختيار دالة الهدف يعتمد على تطبيق معين. من جهة اخرى، فاننا نقترح تعديل على دالة الاداء لتحسين تعميم الشبكات المقترحة وعلى الجانب الاخر، لعلاج التوقف المبكر ومشاكل النهاية الصغرى المحلية.الهدف الرابع هو مقارنة اداء الخوارزميات المذكورة اعلاه فيما يتعلق بقدرة التنبؤ. ثم تطبيق التقنية المقترحة لتقدير تركيز المعادن الثقيلة مثل : النحاس والرصاص والكادميوم والكوبالت والزنك والنيكل في تربة بغداد. اولا، تم اختيار اربعة وستين عينة من التربة من المواقع الملوثة تقع في بعض المناطق في مدينة بغداد (السكنية والصناعية والتجارية والزراعية والطرق الرئيسية). ثانيا، تم اجراء سلسلة من القياسات على عينات التربة وتحليلها لقياس تراكيز المعادن الثقيلة بواسطة اجهزة الامتصاص الطيف الذري (AAS)، فلورية الاشعة السينية (XRF) المطياف الكتلي البلازمي بالتقارون الحثي (ICP - MS) ومن خلالها نحصل على تراكيز اولية لهذه المعادن الثقيلة. ثالثا، محاكاة وتدريب الشبكات المقترحة للحصول على تركيز المعادن الثقيلة بالطريقة المقترحة ومن ثم مقارنة اداء الشبكات المقترحة مع فحص المختبر التقليدي باستخدام مجموعة بيانات التدريب والاختبار. نتائج هذا العمل تبين ان الشبكات المقترحة والمتدربة على القياسات التجريبية يمكن تطبيقها بنجاح لتقدير تركيز المعادن الثقيلة بسرعة ودقة.اخيرا، نقترح بعض الطرق لمعالجة التربة الملوثة باستخدام بعض النباتات العشبية. | There are many aims of this thesis : The first aim is to develop a model equation that describes the spread of contamination through soils which can be used to determine the rate of environmental contamination by estimate the concentration of heavy metals (HMs) in soil. The developed model equation can be considered as a good representation for a problem of environmental contamination. The second aim of this thesis is to design two feed forward neural networks (FFNN) as an alternative accurate technique to determine the rate of environmental contamination which can be used to solve the model equation. The first network is to simulate the soil parameters which can be used as input data in the second suggested network, while the second network simulates to estimate the concentration of heavy metals. The third aim is to develop a conceptual theory of training stage of neural networks from the perspective of functional analysis and optimization methods. Within this formulation, learning means to solve a variational problem by minimizing a performance function associated to the neural network. The choice of the objective functional depends on the particular application. On the other side, we suggest modification of the performance function to improve the generalization of the suggested networks and to treat the early stopping and local minima problems. The fourth aim is to compare the performance of aforementioned algorithms with regard to predicting ability. Then applied the suggested technique to estimate the concentration of heavy metals such as : Copper(Cu), Lead(Pb), Cadmium(Cd), Cobalt(Co), Zinc(Zn) and Nickel(Ni) in Baghdad soils. First, sixty four soil samples were selected from a phytoremediated contaminated site located in some zones in Baghdad city (residential, industrial, commercial, agricultural and main roads). Second, a series of measurements were performed on the soil samples and analyzed measuring of concentrations for heavy metals using devices such as : Atomic Absorption Spectrophotometer (AAS), X - Ray Fluorescence (XRF) and Inductively Coupled Plasma - Mass Spectrometry (ICP - MS) to get initial concentrations for those heavy metals. Third, simulate and train the suggested networks to get the concentration of heavy metals. The performance of the suggested networks was compared with the traditional laboratory inspecting using the training and test data sets. The results of this work show that the suggested networks trained on experimental measurements can be successfully applied to the rapid and accuracy estimation of concentration of heavy metals. Finally, we suggest some methods contaminated soil by using some herbal plants.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: جامعة بغداد
الدرجة: ماجستير
الموضوع الدقيق: الرياضيات
السنة: 2016
الموضوع العام: علوم الرياضيات
اسم المشرف: لمى ناجي محمد توفيق
اسم المؤلف: فرح فيصل غازي

تحسين خوارزميات الحل التام والبحث المحلي لحل بعض مسائل الامثلية التوافقية Improving Exact and Local Search Algorithms for Solving Some Combinatorial Optimization Problems

المستخلص: In mathematics and computer science, an optimization problem (OP) is the problem of finding the best solution from all feasible solutions. OPs can be divided into two categories depending on whether the variables are continuous or discrete. An OP with discrete variables is known as a combinatorial optimization problem (COP). In a COP, we are looking for an object such as an integer, permutation or graph from a finite set.The aim of the research presented in this thesis is to investigate the use of various optimization exacts and heuristics to solve the COP's. This thesis presented in six chapters.In this thesis we interest in discussing three samples of COP; machine scheduling problem (MSP), transposition cipher problem (TCP) and aircraft landing problem (ALP).In the first two chapters, we discuss the main concepts of the COP, the three study cases, the basic techniques and methods for solving the COP respectively.In chapter three, we interesting in MSP, with multiple objective for the 1//(Ci,Ti) problem (P1) and 1//Ci+Ti problem (P3). We investigate the usefulness of precedence rules in solving (P1) and (P3). We found that the complete enumeration method (CEM) gives efficient (and optimal) solutions for (P1) (and (P3)) with number of jobs (n)10, and branch and bound (BAB) gives efficient solutions for (P1) with n15 and optimal solution for (P3) with n80. In addition, we use the local search methods (LSM), to solve the two problems, represented by genetic algorithm (GA) and particle swarm optimization (PSO) with n2000. In general we conclude that PSO serves better than GA. Lastly, a neural network (NN) is constructed to solve problems (P1) and (P3). Two learning algorithms are used to learn the NN; pack propagation (PB) and PSO with and without depending on successive rules (SR). We see that PSO is better than BP in learning NN to obtaining good results.In chapter four, we suggest a new direction in cryptanalysis of TCP, we suggest using the techniques of COP to solve TCP in another word, the TCP treated as one of COP. First a new mathematical formulation for TCP is introduced and proposed some new tools of TCP cryptanalysis. The CEM and modified BAB are developed by using SR to obtain the multi digits CEM (MDCEM) and MDBAB which are helpful in decreasing the CPU time. Classical bees' algorithm (CBA) and shifted key BA (SKBA) are improving the cryptanalysis results. To increase the performance of the mentioned algorithms we construct cryptanalysis system for TCP to find exact solution (as possible) for n20 in reasonable time, which is called SR keys BA (SRKBA). The main result of this thesis is suggesting a general solving system for COP specially, when the problem submits to SR.Chapter five focused in one of the important problems of COP; ALP. A new improvement in a heuristic method, called parallel improving algorithm (PIA), is introduced, the new algorithm called modified PIA (MPIA) which is serves better than PIA. The CEM is used to solve ALP using two techniques; exhaustive search method (ESM) which gives optimal solution but in unreasonable time for n>9 while MPIA gives approximation solutions for n9 in 6 seconds. Lastly, hybridization is proposed between MPIA and CBA, which is called improvement CBA (ICBA). ICBA gives optimal solutions in solving ALP for n<50 and near optimal for n=50.In chapter six, some conclusions together with some suggestions for future researches have been given.The exact and heuristics methods all were tested by programming them using version 10.0 of Delphi Language and MATLAB, and running on Processor Intel(R) Core (TM) i3 CPU, 2.53 GHz, Core(s), with Ram 1.21 GB computer.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: الجامعة المستنصرية - كلية التربية للعلوم الصرفة
الدرجة: دكتوراه
الموضوع الدقيق: الامثلية العددية
السنة: 2015
الموضوع العام: علوم الرياضيات
اسم المشرف: طارق صالح عبد الرزاق
اسم المؤلف: فائز حسن علي

مسالة السيطرة الامثلية التقليدية المستمرة لمعادلات تفاضلية جزئية The Continuous Classical Optimal Control Problem of Partial Differential Equations

المستخلص: الهدف الرئيسي لهذه الرسالة هو دراسة مسالة السيطرة الامثلية التقليدية المستمرة لزوج من المعادلات التفاضلية الجزئية الخطية واللاخطية من النوع المكافئ )stateفي برهان مبرهنة وجود ووحدانية الحل للحالة ( Galerkin حيث استخدمنا طريقة لزوج من المعادلات المذكورة اعلاه ولكن من النوع اللا خطي عندما يكون متجه السيطرة التقليدية المستمرة ثابت . قمنا ايضا ببرهان مبرهنات خاصة بوجود سيطرة (متجه السيطرة) التقليدية المستمرة لزوج من المعادلات التفاضلية الجزئية الخطية واللاخطية من النوع المكافئ. برهنا ايضا مبرهنة وجود ووحدانية الحل لزوج المعادلات التفاضلية الجزئية الخطية واللاخطية للحالة. طورت بشكل يتناسب مع المسالة Kuhn - Tucker - Lagrange’s Multipliers مبرهنات السيطرة التقليدية المستمرة المقترحة في هذه الرسالة وصيغت وبرهنت مبرهنتا الشرط الضروري لوجود السيطرة الامثلية | The main aim of this thesis is to study the continuous classical optimal control problem of a couple of linear and nonlinear parabolic partial differential equations. With a suitable assumptions, the existence and the uniqueness of solution of the state vector of couple of linear parabolic PDEs for a given continuous classical control vector are proved by using Galerkin method. The existence theorems of a continuous classical optimal control vector associated with a couple of nonlinear parabolic equations are developed and proved. The existence and the uniqueness theorem of a solution of the couple of adjoint equations associated with the considered state equations of nonlinear parabolic equations with equality and inequality constraints is also proved once again. The Kuhn - Tucker - Lagrange multipliers theorems are developed and used to prove the necessary conditions theorem and the sufficient conditions theorem of optimality of a couple of nonlinear parabolic equations with equality and inequality constraints
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: الجامعة المستنصرية - كلية التربية للعلوم الصرفة
الدرجة: ماجستير
الموضوع الدقيق: الرياضيات
السنة: 2015
الموضوع العام: علوم الرياضيات
اسم المشرف: جميل اميرعلي الهواسي
اسم المؤلف: غفران مناتي كاظم

الحل العددي لبعض المعادلات التفاضليه باستخدام تحويل لاكير Numerical Solution for some Differential Equations via Laguerre Transform Approach

المستخلص: The main aim of this work is to introduce new formulae that can be used to deal with LT and to utilize them for solving different types of DEs.A new simple general formula is derived to evaluate the LT of the higher derivatives of a variable. The new formula is easily modeled by a computer program, and there is no need for tedious operations of successive integration by part, as in the conventional method.This work proposes a method utilizing LT to solve ODE's (linear and nonlinear, homogeneous or inhomogeneous, boundary or initial value problems), which is explained and implemented in different examples. The results are in a good agreement with the analytical solution.Two other new methods are proposed, utilizing LT to solve PDE's with one spatial dimension. The two methods are explained and implemented in different examples, and the results show a good agreement with the analytical solutions.Another new method, utilizing LT, is proposed to solve PDE's with two spatial dimensions. The method is implemented to solve heat equation with two spatial dimensions and the results show a good agreement with that of finite difference solution. The method is also modified to achieve image smoothing as a global smoothing technique. The new image smoothing technique is compared with a finite difference technique for image smoothing, which is a local smoothing technique. The results of the proposed new technique show better smoothing (less fogy) with an expenditure of a long execution time.Finally, it is worth to mention that all the programs used in this work have been coded by the MATLAB 7 system environment
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: الجامعة المستنصرية - كلية التربية للعلوم الصرفة
الدرجة: ماجستير
الموضوع الدقيق: التحليل العددي
السنة: 2015
الموضوع العام: علوم الرياضيات
اسم المشرف: ايمان علي حسين
اسم المؤلف: غصون سعيد عبد محمد

طرق تكرارية موثوقة لحساب تراكيز ثنائي اوكسيد الكاربون الممتص بواسطة فينيل غلايسيدل الايثر Reliable Iterative Methods for Calculating the Concentrations of Carbon Dioxide Absorbed into Phenyl Glycidyl Ether

المستخلص: In this thesis, two reliable iterative methods are used to calculate the concentrations of carbon dioxide CO2 and phenyl glycidyl ether PGE. The first one is the variational iteration method. It is used to get an approximate solution for a system of two coupled nonlinear ordinary differential equations which represent the concentrations of CO2 and PGE. The other method is the standard homotopy analysis method which is implemented on this system. Formerly, this system has been solved by the Adomiandecomposition method. In solving this system by Adomian’s method, the nonlinearity needs calculating the Adomian’s polynomials. On the other hand, the two methods do not require any assumptions like the calculating of the Adomian’s polynomials. In this system there are boundary conditions of Dirichlet type and the other is a mix of Neumann and Dirichlet type. Our calculations are evidenced by tables and figures for the analysis of the maximal error remainder values. The variational iteration method givesapproximate solutions with fast convergence. Comparison with the results obtained by the Adomian decomposition method shows that the numerical solutions obtained by the variational iteration method converge faster than those of Adomian's method. Also, the homotopy analysis method which is implemented on this system has a very fast convergence in giving approximate solutions. Moreover, the numerical solutions resulted from the homotopy analysis method converge faster than those of Adomian's methodwhich has been implemented previously for the same problem. The numerical results also show high rates of convergence which are obtained at the increasing of the iterations. The used software of the contained calculations in our study is Mathematica 9.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: جامعة بغداد
الدرجة: ماجستير
الموضوع الدقيق: الرياضيات
السنة: 2015
الموضوع العام: علوم الرياضيات
اسم المشرف: مجيد احمد ولي
اسم المؤلف: غسان حسن محمود راضي
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