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دور الانزيمات المحللة للبروتين المنتجة من بكتريا Pseudomonas aeruginosa المعزولة محليا في تقرح القرنية == Role of Proteases Produced by Pseudomonas aeruginosa in Corneal Ulcer ( Keratitis)

Author name: ايمان جواد كاظم
General topic: Biology
Specific topic: Microbiology
Degree: Doctorate
University: University of Baghdad
Language: English
University location: Baghdad
First pages:
Abstract: تضمنت الدراسة تاثيرات الاانزيمات المحللة للبروتين ( Proteases) المنتجة من بكتريا Pseudomonas aeruginosa المعزولة من التهاب القرنية القيحي والجروح, حيث جمعت (200) عينة شملت (150) عينة من مسحات العيون المصابة بالتهاب القرنية و(50) عينة من مسحات الجروح المختلفة. وقد تم الحصول على 17 (%8.5) عزلة بكتيرية من هذه المسحات تعود للنوع P. aeruginosa . وقد تم تشخيص العزلات بوساطة الاختبارات الكيموحيوية. ( 13 عزلة بكتيرية (% 8.7) من التهاب القرنية, و4 عزلات بكتيرية (%8) من الجروح). اظهرت نتائج الكشف عن قابلية البكتريا على انتاج انزيمات البروتيزات, ان 13 عزلة بكتيرية (76.5) كانت منتجة لانزيم Elastase ( 10 عزلة بكتيرية (%76.9) من التهاب القرنية و3 عزلة بكتيرية (%75) من الجروح ), ولوحظ ان العزلتين البكتيريتين P7 , وP11 من التهاب القرنية, وP2من الجروح اعطت اكبر منطقة تحلل 8, 10, 10) مليمتر (على التوالي. كما بينت النتائج ان الكشف النوعي عن قابلية العزلات البكتيرية P. aeruginosa على انتاج انزيم البروتيز القاعدي باستعمال وسط اغار الحليب المقشود (Skim milk agar) اظهر ان العزلات البكتيرية المعزولة جميعها من مرضى التهاب القرنية ومسحات الجروح لها القابلية على انتاجه, كانت العزلة البكتيرية P12 المعزولة من التهاب القرنية الافضل حيث اعطت اكبر منطقة تحلل 22) مليمترا( . في حين ان نتائج الكشف عن قابلية هذه العزلات البكتيرية على انتاج هذا الانزيم باستعمال وسط مرق الكازئين (Casein broth) , بينت ان العزلات البكتيرية المعزولة جميعها من مرضى التهاب القرنية كانت ذات فعالية انزيمية وكانت العزلة البكتيرية P12 هي الافضل من حيث الفعالية الانزيمية اذ بلغت الفعالية النوعية للانزيم 97.469) وحدة / مليغرام( . بينما اظهرت %50 من العزلات البكتيرية المعزولة من الجروح فعالية انزيمية. اشارت نتائج قابلية العزلات البكتيرية على انتاج انزيم LasA الى ان العزلات البكتيرية المعزولة جميعها من التهاب القرنية ومن الجروح لها القابلية على انتاج الانزيم, واظهرت العزلة البكتيرية P6 المعزولة من التهاب القرنية اعلى فعالية اذ بلغت 25.94) وحدة / مليغرام (. اما نتائج الكشف عن قابلية العزلات البكتيرية على انتاج انزيم LasD فقد اظهرت ان 8 عزلات بكتيرية (% 61.5) من العزلات البكتيرية المعزولة من التهاب القرنية ذات فعالية انزيمية بلغت ذروتها في العزلة البكتيرية P11 100.465) وحدة / مليغرام ( . و3 عزلات بكتيرية (%75) من العزلات البكتيرية المعزولة من الجروح اعطت فعالية لهذا الانزيم ولكن واطئة جدا تراوحت ما بين 8.797 - 5.557) وحدة / مليغرام(.استخلص انزيمي البروتيز القاعدي ( من العزلة البكتيرية P12 ) وLasA ( من العزلة البكتيرية P6 ) بوساطة النبذ المركزي المبرد للمزروع البكتيري وتمت تنقيتهما جزئيا باستعمال الترسيب بكبريتات الامونيوم (بنسبة اشباع % 80 ) وكروماتوغرافيا التبادل الايوني باستخدام عمود DEAE - Cellulose , حيث ازدادت الفعالية النوعية للانزيمين وبلغت ( 1629.62 وحدة / مليغرام) لانزيم البروتيز القاعدي و( 718.651وحدة / مليغرام ) لانزيم LasA . درس تاثير هذين الانزيمين المنقيين جزئيا في قرنيات عيون الارانب (in vivu) كلا على حدة وبتراكيز مختلفة ( 10, 7, 5) وحدة / مليلتر ( للبروتيز القاعدي و5, 3, 1) وحدة / مليلتر (لانزيم LasA ) حيث اشارت النتائج الى وجود تا ثيرات واضحة لهما في قرنيات عيون الارانب حيث سبب انزيم البروتيز القاعدي عتمة من الدرجة الثالثة ) عتمة في ثلثي الى كل سطح القرنية و/ او انتفاخ متوسط (. اما انزيم LasA فقد سبب عتمة من الدرجة الثانية ) عتمة في ثلثي سطح القرنية و/او انتفاخ طفيف ( . كما درس تاثير هذين الانزيمين في مستخلص البروتينات لقرنيات عيـون الارانب (in vitro) باستعمال الترحيل الكهربائي بهلام متعدد الاكريل امايد, واظهرت النتائج حدوث تحلل وتمسخ تام لحزم بروتينات القرنية وعند الفعالية الانزيمية 10, 7, 5 ) وحدة / مليلتر( لانزيم البروتيز القاعدي وعند الفعالية الانزيمية 5, 3, 1 ) وحدة / مليلتر( لانزيم Las A. | The study is included the effects of proteases enzymes producing by Pseudomonas aeruginosa, which isolated from keratitis and wounds .two hundred samples were collected, 150 samples of them were keratitis and fifity samples were wounds.Seventeen isolates (8.5 %) were obtained and diagnosed as P. aeruginosa.13 isolates (8.7%) from keratitis and 4 isolates (8%) from wound swabs. All bacterial isolates were diagnosed by biochemical tests. The production of elastase were tested by using elastin agar.Thirteen isolates (76.5%) had the ability to producing elastase (10 isolates (76.9 %) from keratitis and 3 isolates (75%) from wounds). The isolates P7 and P11from keratitis and P2 from wounds had the larger hydrolysis Zone ( 10, 10, 8 millimetre ) respectively.The production of alkaline protease were tested by using solid cultures ( skim milk agar ), all of them (keratitis and wound swabs ) had the ability to production of the enzyme, the isolates P12 isolated from keratitis had the larger hydrolysis zone ( 22 millimetre). Also the production of the enzyme were tested in liquid cultures ( casein broth ), all isolates from keratitis had the ability to production of the enzyme, the isolates P12 had the specific activity 97.469 U / mg, while 50 % of the wounds isolates had the ability to producing alkaline protease. The production of LasA enzyme were tested, all isolates (keratitis and wound swabs ) had the ability to production of the enzyme, the isolates P6 isolated from keratitis had higher specific activity 25.94 U / mg.The production of LasD enzyme were tested,8 isolates (61.5 %) from keratitis isolates had the ability to producing LasD enzyme. The isolate P11 had higher specific activity 100.465 U / mg, while 3 isolates (75 %) from wounds isolates had lower ability to producing LasD enzyme including between ( 5.557 - 8.747 U / mg). The alkaline protease was extracted from P12 isolate and LasA enzyme was extracted from P6 isolate. The enzymes were extracted by cooling centrifuge and them purified partially by precipitation with ammonium sulphate ( 80 % ) and ion exchange chromatography by DEAE - Cellulose the specific activity for enzymes were increased,which reached and 1629.62 U / mg for alkaline protease enzyme and 718.651 U / mg for LasA enzyme. The results of the enjection of alkaline protease and LasA enzyme in eyes corneal rabbits (in vivu) showed that both enzymes had the obvious effect on the cornea. The alkaline protease (5, 7, 10 U / ml ) caused damage for the cornea grade III melting ( two - thirds to all of the corneal surface ) and / or moderate bulging. Also the LasA enzyme ( 1, 3, 5 U / ml ) caused damage for the cornea grade II melting ( one - thirds to two - thirds of the corneal surface) and / or mild bulging.The protein profile of extract corneal proteins treated with alkaline protease ( 5, 7, 10 unit / ml) and LasA enzyme ( 1, 3, 5 unit / ml) (in vitro) by polyacrylamide gel electrophoresis showed hydrolysis and complete denaturation of corneal proteins bands.

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

Author name: ياسمين سلمان كاظم
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: 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 ????̅ +???? ̅ ).

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

Author name: هبة عصام عبد الوهاب
Supervisor name: علي شكر محمود
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: 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.

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

Author name: هالة عبود جاسم
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: 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.

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

Author name: ميثم نعيم صالح
Supervisor name: مازن مانوئيل الياس
General topic: Laser Science
Degree: Doctorate
Language: English
University location: Baghdad
First pages:
Abstract: 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.

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

Author name: فهد محمد عبد الحسين
Supervisor name: تحرير صفاء منصور
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: 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.

التحقق عمليا من بروتوكول البينغ بونغ

Author name: علاء جبار جمعة
Supervisor name: شيلان خسرو توفيق
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: 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.

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

Author name: حسنين مجيد حسين
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: 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.

الليف البلوري الفوتوني لاستشعار المجال المغناطيسي == Photonic crystal fiber magnetic sensor

Author name: احمد عدنان محمد
Supervisor name: عبد الهادي مطشر الجنابي
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: 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.

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

Author name: احمد عبد الكريم علي
Supervisor name: عبد الهادي مطشر الجنابي
General topic: Laser Science
Degree: Doctorate
Language: English
University location: Baghdad
First pages:
Abstract: 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.

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

Author name: نور ياسر حسون حمادي
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:

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

Author name: ندى حسين حمودي
Supervisor name: علي شكر محمود
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:

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

Author name: عمار محمد طعيمة
Supervisor name: مازن مانوئيل الياس
General topic: Laser Science
Degree: Doctorate
Language: English
University location: Baghdad
First pages:
Abstract: 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.

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

Author name: عبير احمد شهاب العبيدي
General topic: Laser Science
Degree: Doctorate
Language: English
University location: Baghdad
First pages:
Abstract: 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.

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

Author name: رواء كاظم زرزور
Supervisor name: حنان جعفر طاهر
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: 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

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

Author name: ايسر عبد الرزاق الاميري
Supervisor name: حسين علي جواد | زينب فاضل مهدي
General topic: Laser Science
Degree: Doctorate
Language: English
University location: Baghdad
First pages:
Abstract: 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.

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

Author name: فرح فيصل غازي
Supervisor name: لمى ناجي محمد توفيق
General topic: Mathematics
Specific topic: Mathematics
Degree: Master
University: University of Baghdad
Language: English
University location: Baghdad
First pages:
Abstract: 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.

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

Author name: غسان حسن محمود راضي
Supervisor name: مجيد احمد ولي
General topic: Mathematics
Specific topic: Mathematics
Degree: Master
University: University of Baghdad
Language: English
University location: Baghdad
First pages:
Abstract: 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.

طرق تكرارية كفوءة لحل مسائل القيم الحدودية ذات النقطتين == Efficient Iterative Methods for Solving Two - Point Boundary Value Problems

Author name: علي حسين عباس
Supervisor name: مجيد احمد ولي
General topic: Mathematics
Specific topic: Mathematics
Degree: Master
University: University of Baghdad
Language: English
University location: Baghdad
First pages:
Abstract: قدمت في هذه الرساله ثلاثه طرق تكراريه موثوقه لحل مسائل القيم الحدوديه ذات النقطتين الخطيه وغير الخطيه. الطريقه الاولى تتناول تطبيق الاسلوب الشبه تحليلي لحل هذه المشكله. وفي هذه الطريقه تم الحصول على الحل بشكل متسلسله وبحسابات سهله. ان النتائج التي تم الحصول عليها لقيم الخطا المتبقي تبين ان هذه الطريقه فعاله جدا وموثوقهالطريقه الثانيه هي الطريقه التكراريه المطوره وتسمى DJM لحل هذه المشكله. هذه الطريقه تعطي حلا تقريبيا مع تقارب سريع. النتائج العدديه تثبت ان الطريقه المستخدمه هي طريقه موثوقه وفعاله. اما الطريقه الثالثه والاخيره تسمى طريقه متسلسله القوى لحل هذه المشكله. وهناك بعض الامثله العدديه قدمت لاثبات كفاءه هذه الطريقه وكما استخدمت بعض التطبيقات على هذه المشكله وحلها بواسطه هذه الطرق المذكوره. ان البرنامج المستخدم لايجاد هذه النتائج العدديه هو الماثيماتيك | In this thesis, three reliable iterative methods have been introduced to solve linear and nonlinear two - point boundary value problems (TPBVPs). The first method deals with the implementation of the semi - analytic method namely (TAM) to solve two - point boundary value problems. In TAM, the solution is obtained in the series form with easily computed components. The results of the maximal error remainder values show that the present method is very effective and reliable. The second method namely a new iterative method (NIM or DJM) to solve the TPBVPs. DJM gives an approximate solution with fast convergence. The numerical results prove that the suggested method is reliable and effective. The third and final method is called Power series method (PSM). It is presented to solve TPBVPs. Numerical examples are given to demonstrate the efficiency of the proposed method and some application of TPBVPs will be solved by this methods. The software used for the numerical calculation was MATHEMATICA® 10.0.

بعض طرائق التقدير لمعلمتي توزيع باريتو من النوع الاول باستخدام المحاكاة مع تطبيقات عملية == Some Estimation Methods for the Parameters of Pareto type I by using Simulation with Practical Application

Author name: عدويه ناجي عطيوي الخشالي
Supervisor name: حازم منصور كوركيس
General topic: Mathematics
Specific topic: Applied Mathematics
Degree: Master
University: University of Baghdad
Language: English
University location: Baghdad
First pages:
Abstract: تناولت رسالة الماجستير هذه مناقشة العديد من الخصائص الاحصائية لتوزيع باريتو من النوع الاول ذو المعلمتين، كذلك تم التطرق الى العلاقة بين توزيع باريتو وعدد من التوزيعات المستمرة الاخرى.ان الغرض من الرسالة هو مقارنة طريقة بيز القياسية مع اربعة من الطرق التقليدية لتقدير معلمتي الشكل والقياس باستخدام طريقة مونت - كارلو لمحاكاة نماذج مختلفة.وقد تبين من خلال الدراسة ان مقدر بايز افضل من المقدرات الاخرى لتقدير المعالم باستخدام متوسط مربعات الخطا (M.S.E) من اجل المقارنة بين افضلية مقدرات طرائق التقدير المختلفة ولحجوم العينات المختلفة. علاوة على ذلك، تناول الباحث بعض التطبيقات الحقيقية من الحياة والتي تتوزع بعضها توزيع باريتو.تم استخراج النتائج عن طريق كتابة برامج باستخدام برنامج الماتلاب MATLAB R2013b. | In this thesis several statistical properties for Pareto distribution type one with two parameters had been discussed. The relationship of Pareto distribution with many other continuous distributions is also presented. However, the main purpose of this thesis is to compare between standard Bayes method and four classical methods to estimate the shape and scale parameters by using Monte Carlo simulation method for different models. It had been shown that standard Bayes estimator is better than other estimators in the sense of MSE by assuming different sample sizes. Moreover, some real life applications related to Pareto distribution are given. The computer programs are writing and the run is made by using MATLAB (R2013b) professional software.

تصميم شبكات عـصبية ملائمة لحل مسائل القيم الذاتية وتطبيقاتها == Design Suitable Neural Networks to Solve Eigen Value Problems and It?s Application

Author name: عثمان مهدي صالح
Supervisor name: عثمان مهدي صالح
General topic: Mathematics
Specific topic: Applied Mathematics
Degree: Master
University: University of Baghdad
Language: English
University location: Baghdad
First pages:
Abstract: الهدف من هذه الرسالة هو تصميم شبكات عصبية ملائمة ذات تغذية تقدمية كطريقة لحل مسائل القيم الذاتية للمعادلات التفاضلية الاعتيادية الشاذة وغير الشاذة ذات الشروط الحدودية. الشبكة المقترحة تتعلق بحساب القيم الذاتية والدالة الذاتية المرافقة لها والتي تمثل الحل الغير صفري لنموذج المسالة.ايضا ناقشنا عدد من خوارزميات الاداء ذات المستوى العالي المستخدمة في خوارزميات تدريب الانتشار المرتد للشبكات العصبية ذات التغذية التقدمية وعرض نتائج المقارنة الحاصلة من تطبيق MATLAB مثل ﻟﻴفنبرﻙ - ماركواردت , شبيه نيوتن, تنظيم بيزن, ومن ثم تسريع اداء الشبكات المقترحة من خلال تعديل خوارزميات التدريب هذه, حيث ان بعضها يمتلك نسبة تقارب سريعة جدا لشبكات ذات احجام معقولة.الهدف الاخر لهذه الرسالة هو تحسين خوارزمية التدريب ﻟﻴفنبرﻙ - ماركوارت من خلال الاختيار المناسب للمعامل μk والذي يضمن التقارب لخوارزمية التدريب هذه.ايضا عالجنا عدة مشاكل واجهتنا اثناء تقنية التدريب مثل : التوقف المبكر, خزن الذاكرة , التنظيم وحساب مصفوفة هيسين ومعكوسها.اخيرا تم توضيح الشبكات المقترحة من خلال حل مسائل متنوعة ومقارنتها مع حلول بطرق مختلفة اخرى لاثبات سرعة , دقة وفاعلية استخدام تقنية الشبكات في حل هذا النوع من المعادلات. | The aim of this thesis is to design suitable feed forward neural networks to present a method to solve eigenvalue problems for non - singular ordinary differential equations with boundary conditions. The suggested networks concerned with the computation of eigenvalues and associated eigenfunction which represent the nontrivial solution of the problem model. Also, we will discuss several high performance algorithms used in back propagation training of the feed forward neural networks and present comparative results obtained in MATLAB implementation such as : Levenberg - Marquardt, quasi - Newton and Bayesian regularization, update procedure, then speeding suggested networks by modification these training algorithms, many of them have a very fast convergence rate for reasonable size networks.Other aims of this thesis is to modify Levenberg - Marquardt training algorithm by suitable choice of the parameter μk which guarantee super linearly convergence for this training algorithm. Also, we treat many problems that confront during the training technique such as : early stopping, memory storage, regularization and calculating of Hessian matrix and its inverse.Finally, illustrate the suggested networks by solving a variety of model problems and present comparisons with solutions obtained using other different methods to show speed, accuracy and effectiveness of using the networks technique for solving this type of equations

المقاسات الجزيئة المقاسات المستحوذة على 2 وبعض اعماماتها == 2 - Absorbing Submdules (Modules) and Some of Their Generalizations

Author name: عبد الرحمن عبد الله حرفش
Supervisor name: انعام محمد علي هادي
General topic: Mathematics
Specific topic: Mathematics
Degree: Master
University: University of Baghdad
Language: English
University location: Baghdad
First pages:
Abstract: Let R be a commutative ring with identity, and let M be a unitary left Rmodule. Prime ideals one of the main concepts in ring theory and many generalizations of this concept are introduced such as strongly prime ideals, almost prime ideals, weakly prime ideals, semi - prime ideals, weakly semiprime ideals and 2 - absorbing ideals. Moreover each of the above concepts generalized to submodules. Main goals in this work :  Presenting a comprehensive study of 2 - absorbing submodules and giving many new characterizations and properties related with this concept. Also we use this concept to define and study a new class of modules which is called 2 - absorbing modules.  Introducing and studying many generalizations of 2 - absorbing submodules, 2 - absorbing modules. In fact we introduce and study semi - 2 - absorbing submodules, semi - 2 - absorbing modules, Endo 2 - absorbing submodules, Endo semi - 2 - absorbing submodules, Endo 2 - absorbing modules and Endo semi - 2 - absorbing modules.  Presenting other kinds of 2 - absorbing submodules(resp.2 - absorbing modules) namely small 2 - absorbing submodules (resp. small 2 - absorbing modules ). Then Endo small 2 - absorbing submodules (resp. Endo small 2absorbing modules) are introduced and studied.

بعض الطرق التكرارية الموثوقة والكفوءة لحل معادلات دفنك == Some Reliable and Efficient Iterative Methods for Solving Duffing Equations

Author name: سيل غني عبد الرزاق
Supervisor name: مجيد احمد ولي
General topic: Mathematics
Specific topic: Mathematics
Degree: Master
University: University of Baghdad
Language: English
University location: Baghdad
First pages:
Abstract: ان الهدف الرئيسي من هذه الرسالة هو حل معادلة دفنك في كلا النوعين قليلة الاهتزاز والمهتزة. في هذه الرسالة هناك طريقتين تكراريتين استخدمتا لحل معادلة دفنك. الطريقة الاولى تسمى الطريقة التكرارية المطورة او (Daftardar - Jafari method (DJM)) والطريقة الثانية تسمى الطريقة شبه التحليلية او (TAM)) Temimi - Ansari method). قد تم حل بعض الامثلة لتوضيح الكفاءة والدقة العالية للطرق المقترحة من خلال النتائج كذلك تمتاز الطرق المقترحة بعدم حاجتها الى متطلبات اخرى. ايضا قد تم مقارنة الطرق المقترحة مع طرق اخرى ناجحة مثل ( الطريقة التغايرية التكرارية ) وطريقة ادومين التي تم ذكرهما لمعرفة فعالية الطرق التي تمت الدراسة من خلالها. الفصل الاول من هذه الرسالة تم التركيز فيه على معادلة دفنك والوجود والوحدانية للحل. الفصل الثاني من الرسالة يتناول تطبيق (الطريقة التكرارية المطورة ) لحل معادلة دفنك قليلة الاهتزاز والمهتزة مع حالات اخرى لمعادلة دفنك. ايضا الطريقة الثانية (الطريقة شبه التحليلية (قد استخدمت في الفصل الثالث لحل معادلة دفنك في نوعيها قليلة الاهتزاز والمهتزة وكذلك حل حالتان خاصة من معادلة دفنك. في الفصل الرابع تم ذكر تطبيقين على معادلة دفنك وقد تم حلهم الطريقة التكرارية المطورة, الطريقة شبه التحليلية, طريقة ادومين وطريقة التغاير التكرارية.في الفصل الخامس قمنا بعرض مقارنة بين الطريقة التكرارية المطورة, الطريقة شبه التحليلية, طريقة ادومين وطريقة التغاير التكرارية وتم كذلك عرض بعض الاستنتاجات والاعمال المستقبلية وقد تمت الحسابات باستخدم برنامج (الماثيماتيكا) الحاسوبي. | The main aim of this thesis is to solve the two types of Duffing equations : damping and undamping. In this thesis two iterative methods are used for solving Duffing equations. The first method is called new iterative method (NIM) or Daftardar - Jafari method (DJM) and the second method is called semi analytic technique or Temimi - Ansari method namly (TAM). Some examples will be solved to show that the proposed methods are efficient and have high accuracy and does not require any restrictive assumptions. Also, the comparison with some other existing methods, such as variational iteration method (VIM) and Adomain decomposition method (ADM) will be presented to demonstrate the effective of the presented methods. The first chapter of this thesis will be focuse of on some basic concepts of the Duffing equations, existence and uniqueness solution. The second chapter deals with the implementation of the new iterative method (NIM) to solve the damping and undamping Duffing equations and other cases of Duffing equations. Also, the second method semi analytic technique used in third chapter for solve that two types of Duffing equations damping and undamping with other cases of Duffing equations. In chapter four, we state two application of Duffing equation and solve them in DJM, TAM, ADM and VIM. In chapter five we presented the comparison between DJM, TAM, ADM and VIM and, present conclusions and future work. The used software of the contained calculations in our study is Mathematica 9.

المقاسات المجوفه من النمط والمقاسات شبه المجوفه من النمط == Hollow Modules and Semihollow Modules

Author name: سميعه حسون عيدي
Supervisor name: انعام محمد علي هادي
General topic: Mathematics
Specific topic: Mathematics
Degree: Master
University: University of Baghdad
Language: English
University location: Baghdad
First pages:
Abstract: لتكن R حلقه ابدالية ذات محايد وليكن M مقاسا على R. Fleury في 1974 قدم ودرس المقاسات المجوفه، حيث يسمي المقاس M على R مقاسا مجوفا اذا كان كل مقاس جزئي فعلي في M مقاسا جزئيا صغيرا . العديد من الاعمامات للمقاسات المجوفه والمقاسات الجزئيه الصغيره قدمت من قبل العديد من الباحثين، بعض هذه الاعمامات هي : مقاس جزئي صغير من النمط - ، مقاس جزئي صغير من النمط - e، مقاس جزئي من النمط - F، مقاس جزئي صغير من النمط - p، مقاس جزئي صغير من النمط - T، مقاس جزئي شبه صغير، مقاس مجوف من النمط - ، مقاس مجوف من النمط - F ، مقاس مجوف من النمط ps - ، مقاس شبه مجوف. في هذا العمل، دراسة شاملة للمقاسات المجوفه من النمط -  اعطيت. من جهه اخرى قدمت ودرست المقاسات المجوفه من النمط - e، حيث يسمى المقاس M على R، مقاسا مجوفا من النمط - e اذا كان كل مقاس جزئي فعلي من M مقاسا جزئيا صغيرا من النمط - e. لدينا اولا : المقاسات المجوفه  المقاسات المجوفه من النمط -   المقاسات المجوفه من النمط - e لكن معكوس كل منها غير صحيح ويكون صحيحا تحت شروط معينه. العديد من التشخيصات، النتائج والخواص المتعلقة بهذه المفاهيم قد اعطيت. بالاضافه الى هذا، المقاسات شبه المجوفه من النمط -  والمقاسات شبه المجوفه من النمط - e قدمت ، حيث يسمى المقاس M على R مقاسا شبه مجوف من النمط -  (شبه مجوف من النمط - e) اذا كان كل مقاس جزئي فعلي منته التولد هو صغيرا من النمط -  (صغيرا من النمط - e). نتائج وعلاقات مختلفه بين هذه المفاهيم ومفاهيم اخرى ذات صله معها قد قدمت. الى جانب هذا، تم اعطاء اعمامات اخرى للمقاسات الجزئيه الصغيره والمقاسات المجوفه، تسمى شبه - (المقاسات الجزئيه الصغيره من النمط - e) وشبه - (المقاسات المجوفه من النمط - e). كذلك الخواص الاساسية لها قد اعطيت. | Let R be a commutative ring with identity and let M be an R - module. In 1974, Fleury introduced and studied hollow modules, where an R - module M is called hollow if every proper submodule of M is small". Many generalizations of "hollow module" and small submodule are introduced by several reserachers. Some of these generalizations are :  - small submodule, e - small submodule, F - small submodule, p - small submodule, T - small submodule, semi - small submodule,  - hollow module, F - hollow module, ps - hollow module, semihollow module. In this work, a comprehensive study of  - hollow module is given. On the other hand, e - hollow modules is introduced and studied. Firstly we have : Hollow modules   - hollow modules  e - hollow modules,but the converses are not true.However the converses are true under certain conditions. Many characterizations, results and properties related with these concepts are given. Moreover  - semihollow modules and e - semihollow modules are presented, where an R - module M is called  - semihollow (e - semihollow) if every proper finitely generated submodule is  - small (e - small).Various results and relations between these concepts and other related concepts are introduced. Beside these,other generalizations of small submodules and hollow modules, namely semi - e - small submodules and semi - e - hollow modules are introduced. Also their basic properties are given.

استخدام النمذجة الرياضية والشبكات العصبية للسرطان : نمو الورم والعلاج == Employ Mathematical Modeling and Neural Networks for Cancer : Tumor Growth and Treatment

Author name: سجى عبد الرحمن عبد الجبار
Supervisor name: لمى ناجي محمد توفيق
General topic: Mathematics
Specific topic: Mathematics
Degree: Master
University: University of Baghdad
Language: English
University location: Baghdad
First pages:
Abstract: تهدف الرسالة الى ما يلي : ان الهدف الاول هو تقديم وتطوير نموذج رياضي يصف نمو الورم السرطاني , والذي يمكن استخدامه لتحديد معدل نمو السرطان .والهدف الثاني للرسالة هو تصميم شبكة عصبية ذات تغذية تقدمية كتقنية دقيقة متداولة لتحديد معدل نمو السرطان, والذي يمكن استخدامه لحل معادلة النموذج. والشبكة المقترحة تحاكي اولا لتحديد معلمات معادلة النموذج, ومن ثم تحاكى لتقدير معدل النمو السرطاني .واما الهدف الثالث هو تطوير الجانب النظري لمرحلة التدريب للشبكة العصبية من خلال تحسين خوارزمية شبه نيوتن, وتحسين تعميم الشبكة المقترحة ومعالجة التوقف المبكر للشبكة ومشاكل الحدود الدنيا المحلية ايضا.واخيرا الهدف الرابع هو اختبار اداء التصميم المقترح والخوارزميات في تشخيص السرطان وعلى وجه الخصوص تشخيص سرطان المثانة, وكذلك كيفية استخدام معمارية الشبكة العصبية الاصطناعية ذات التغذية التقدمية للمساعدة في تشخيص السرطان في مرحلة مبكرة. | There are many aims of this thesis : The first aim is to introduce and develop a model equation that describes the tumor growth of cancer, which can be used to determine the rate of growth for cancer. The second aim of this thesis is to design feed forward neural network as an alternative accurate technique to predict the rate of the tumor growth for cancer which can be used to solve the model equation. The suggested network is simulating firstly to estimate the parameters of model equation, and then simulates to estimate the rate of the tumor growth. The third aim is to develop a conceptual theory of training stage for neural networks from suggested improvement of quasi Newton algorithm also improve the generalization of suggested networks and treating the early stopping and local minima problems. Finally, the fourth aim is testing the performance of the suggested design and algorithms in diagnosis of cancer with special reference to bladder cancer detection, also provides how the utilization of FFNN technique helps for diagnosis of cancer in early stages.
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