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Article
Different methods for characterizing surface roughness using laser speckle technique
طرائق مختلفة لتوصيف خشونة سطح بأستخدام تقنية الترقيط الليزري

Authors: Sabah M. Hadi صباح محمدهادي --- Mayada B. Al-Quzweny ميادة بدري القزويني
Journal: Iraqi Journal of Physics المجلة العراقية للفيزياء ISSN: 20704003 Year: 2014 Volume: 12 Issue: 23 Pages: 21-29
Publisher: Baghdad University جامعة بغداد

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Abstract

In this work, results from an optical technique (laser speckle technique) for measuring surface roughness was done by using statistical properties of speckle pattern from the point of view of computer image texture analysis. Four calibration relationships were used to cover wide range of measurement with the same laser speckle technique. The first one is based on intensity contrast of the speckle, the second is based on analysis of speckle binary image, the third is on size of speckle pattern spot, and the latest one is based on characterization of the energy feature of the gray level co-occurrence matrices for the speckle pattern. By these calibration relationships surface roughness of an object surface can be evaluated within these relations ranges from single speckle pattern image which was taken from the surface.

في هذا العمل, تم أعتماد تقنية بصرية (تقنية التبقع الليزري) وذلك لقياس خشونة سطح بأستخدام الخواص الاحصائية لنموذج التبقع من وجهة نظر الحاسوب التحليلية لبنية الصورة. تم أستحصال اربعة علاقات معيارية لتغطية مدى واسع من القياس. بنيت العلاقات المعيارية هذه بطرائق مختلفة. حيث بنيت العلاقة المعيارية الاولى بالاعتماد على التباين بين شدات التبقع, أما الطريقة الثانية فكان اعتمادها على تحليل الصورة بالنظام الثنائي (بدلالة 1,0) للتبقع. أعتمدت الطريقة الثالثة على حجم بقعة التبقع أما الطريقة الاخيرة فقد اعتمدت على ايجاد ميزة الطاقة لصورة مشتقة من صورة نموذج التبقع. من هذه العلاقات المعيارية يمكن ايجاد خشونة أي سطح ضمن مدى هذه العلاقات وذلك من التقاط صورة واحدة لنموذج التبقع واختبارها مع المديات الموجودة ووفقاً للمعلومات المستحصلة للعلاقات المعيارية الاربعة.

Keywords

roughness --- speckle --- CCD camera.


Article
Bleaching effect on surface roughness and microhardness of dentin

Authors: Abdul-haq A SULIMAN --- Neam N YUOSFANI
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2002 Volume: 2 Issue: 1 Pages: 20-26
Publisher: Mosul University جامعة الموصل

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Abstract

The main objectives of this study were to determine the effects of the bleaching solutions on the surface characteristics of dentin namely, microhardness and surface roughness. Sixteen dentin samples were prepared for the measurements. Teeth mounted in an acrylic resin blocks for microhardness measurements and surface roughness. The bleaching was performed by immersion of each sample in (35%) hydrogen peroxide at (37)°C in an incubator for a period of one hour. Vicker'smicrohardness instruments used for microhardness measurements and profilometertesting machine was used to evaluate surface Toughness. Two measurements were taken from each samples one before and the other after bleaching procedure. The data were collected and analyzed using analysis of variance and t-test, The results showed that the microhardness of dentin is greater before bleaching than the mean after bleaching procedures. This indicated that the bleaching solution used in this study reduced the microhardness of the dentin in vitro. There are slight changes in the mean value of the surface roughness of dentin after bleaching, which is statistically not significant.

Keywords

Bleaching --- roughness --- microhardness


Article
Effect of Current on Average Surface Roughness of Borosilicate Glass at EDM Machining and Comparison with Numerical Programs
تاثیر التیار المستخدم في عملیات القطع بالشرارة الكھربائیة على الخشونة السطحیة لزجاج البوروسیلیكات ومقارنتھا مع نتائج تحلیلیة

Authors: Wathik I. Mahdi --- Maan A. Tawfiq --- Shukry H. Aghdeab
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2009 Volume: 27 Issue: 6 Pages: 1026-1038
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Machining of electrically non-conducting materials like glass is still a major problem. The principle of electric arc was used to generate high electrical discharge (spark) at high currents to machine non-conducting materials at any hardness, which is a new approach.EDM system was build for machining of non-conducting cutting materials such as glass with new technology including the use of powder (graphite) mixed for dielectric solution (tap water) by supplied AC current values (200, 250, 300, 350 and 400A). Voltage of (70V) was used to cut 3mm thickness of borosilicate glass (BSG) to obtain the average surface roughness (Ra) of about (0.003-0.012μm) but the Ra before the machining was (0.005-0.006μm).Numerical program called "Simulent" has been used to investigate the process control for EDM by using GN, BPN, PN and VQN that could predict the Ra with accuracies of 94.236, 94.034, 96.628 and 92.875% respectively from training data sets.The differences on the Ra at different network models for 3mm thickness of BSG never exceed (8%) from testing data sets while the comparison of numerical results with experimental results of Ra among the measured values and prediction various network models, shows a differences between (1-8%).The best predication accuracy is by the use of PN than other network models.

قطع المواد غير الموصلة كهربائيا مثل الزجاج مازال مشكلة رئيسية 0مبدا القوس الكهربائي تم استخدامه لتوليد شرارات كهربائية ع الية عند تيارات عالية وبوجود مسحوق الكرافيت المضاف للماءالصافي واستخدام التيار المتناوب لقطع المواد غير الموصلة عند اية صلادة وهي طريقة جديدة تم بناء منظومة شرارة كهربائية لقطع مواد غير موصلة مثل الزجاج مع تقنية جديدة متضمنة(70V) استخدام مسحوق الكرافيت ممزوج مع الماء الصافي بتسليط تيار متناوب 0تم استخدام فولتية 3) للحصول على متوسط خشونة mm) 200-400 ) لقطع سمك A) وقيم تيار متناوب تتراوح بين ( 0.003-0.012 ) لكن الخشونة السطحية قبل التشغيل كانت - 0.005 μm) سطحية صغير جدا حوالي للسيطرة على عملية القطع بالشرارة (Simulent) 00.006 استخدمة برنامج رقمي يسمى μm) (Ra) متمثل بالتنبوء بمعدل الخشونة السطحية (GN, BPN, PN and VQN) الكهربائية باستخدام 1027 94.236 ) على التوالي من مجموعة بيانات , 94.034, 96.628 and وبدقة تتراوح (% 92.875 التدريب.3) لزجاج mm) الفرق لمعدل الخشونة السطحية عند نماذج لشبكة م ختلفة ولسمكالبوروسيليكات لايتجاوز عن (% 8) من مجموعة بيانات الاختبار 0مقارنة النتائج الرقمية مع النتائج التجريبية بين ان معدل الخشونة السطحية بين القيم المقاسة والتنبؤات لمختلف موديلات الشبكة وكان (1- الفرق بين .(% 8عن موديلات الشبكة الاخرى بسبب ان الشبكة المذكورة (PN) افضل دقة متوقعة باستخدام تستخدم مسار رياضي مفرد وموسع اقل من موديلات الشبكات الاخرى 0

Keywords

Surface Roughness --- EDM --- MRR --- REW.


Article
Study the Effect of Electrical Current on Average Surface Roughness of Borosilicate Glass at EDM Machining and Comparison Using Matlab Program

Authors: Shukry H. Aghdeab --- Ahmed A. Abulwahhab
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2011 Volume: 29 Issue: 6 Pages: 1157-1165
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Machining of electrically non-conducting materials like glass is still a majorproblem. The principle of electric arc was used to generate high electricaldischarge (spark) at high currents to machine non-conducting materials at anyhardness.EDM system was build for machining of non-conducting cutting materialssuch as glass including the use of powder (graphite) mixed for dielectric solution(tap water) by supplied DC current values (200, 250, 300, 350 and 400A). Voltageof (70V) was used to cut 3mm thickness of borosilicate glass (BSG) to obtain theaverage surface roughness (Ra) of about (0.003-0.012μm).Matlab program has been used to investigate the process control for EDM thatcould the Ra experimental and theoretical with accuracies of 94.236, 94.034,96.628 and 92.875% respectively.From the reading of the magnitude of the roughness it was found that differencesbetween the theoretical and experimental values for 3mm thickness of BSG wasnever exceed (8%).

Keywords

Surface Roughness --- EDM --- MRR --- REW


Article
STUDYING ROUGHNESS OF STEEL CUTTING PROCESS BY LASER
د ا رسة خشونة قطع الفولاذ باللیزر

Author: Jasim Hassan Rasheed جاسم حسن رشید
Journal: DIYALA JOURNAL OF ENGINEERING SCIENCES مجلة ديالى للعلوم الهندسية ISSN: 19998716/26166909 Year: 2012 Volume: 5 Issue: 1 Pages: 181-190
Publisher: Diyala University جامعة ديالى

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Abstract

ABSTRACT: Practical work on laser – Steel cutting Process for thin sheet to gain better informations on cut quality .Relationship between cutting speed and roughness of the surface at different pressures is shown . It was found that the smoothness of the cut Process is proportional with the cutting speed without any apparent limitation . Roughest is also Proportional with Pressure of the oxygen gas which is used with CO2 laser beam.Keywords: "Roughness , Steel , Cutting , Laser".

الخلاصةاجراء عملي لقطع شریحة فولاذ رقیقة قد تم انجازه لغرض الحصول على معلومات افضل بخصوص نوعیة القطع .كذلك تم تبیان الصلة بین سرعة القطع وخشونة السطح المقطوع عند ضغوط مختلفة حیث وجد ان نعومة السطح تتناسب طردیا مع سرعة القطع دون ظهور تحدید لهذا التناسب . كما لوحظ ان خشونة السطح المقطوع هي الاخرى تتناسب طردیا مع زیادة ضغط غاز الاوكسجین المستخدم مع لیزر ثاني اوكسید الكاربون .


Article
The surface roughness of new fluoride releasing material after using three polishing protocols and storage in artificial saliva

Author: Maha A. Habeeb مها حبيب
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2013 Volume: 25 Issue: 1 Pages: 21-26
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Prophylaxis methods are used to mechanically remove plaque and stain from tooth surfaces; suchmethods give rise to loss of superficial structure and roughen the surface of composites as a result of their abrasiveaction. This study was done to assess the effect of three polishing systems on surface texture of new anteriorcomposites after storage in artificial saliva.Materials and methods: A total of 40 Giomer and Tetric®N-Ceram composite discs of 12 mm internal diameter and3mm height were prepared using a specially designed cylindrical mold and were stored in artificial saliva for onemonth and then samples were divided into four groups according to surface treatment:Group A (control group):10 specimens received no surface polish and were subdivided into A1 (Giomer) and A2(Tetric®N-Ceram). Group B: 10 specimens received polishing with Air polishing devise (APD) and were subdivided intoB1 (Giomer) and B2 (Tetric®N-Ceram). Group C: 10 specimens received polishing with pumice and brush and weresubdivided into C1 (Giomer) and C2 (Tetric®N-Ceram). Group D: 10 specimens were polished with pumice andrubber cup and were subdivided into D1 (Giomer) and D2 (Tetric®N-Ceram). Testing was done by means ofprofilometer and statistically analyzed using analysis of variance test (ANOVA), LSD and student t-test. Also sampleswere photographed by special orthoplane camera using light polarizing microscope.Results: The results showed a highly statistical significant difference in surface roughness among Giomer subgroupsP<0.05. Also there was a highly significant difference P<0.05 when comparing Tetric subgroups according to type ofsurface treatment. Furthermore there was non-significant difference P>0.05 between groups according to the typeof restorative material used.Conclusion: The use of prophylactic surface treatment significantly increased Giomer and Tetric ceram surfaceroughness and the use of rotating brush has shown the roughest surface among all other types of prophylacticprotocols also Giomer had shown more surface roughness than Tetric ceram although the difference was notsignificant.


Article
Optimal Design of Cylinderical Ectrode Using Neural Network Modeling for Electrochemical Finishing

Author: Nadhim M. Faleh
Journal: Iraqi Journal of Chemical and Petroleum Engineering المجلة العراقية للهندسة الكيمياوية وهندسة النفط ISSN: 19974884/E26180707 Year: 2013 Volume: 14 Issue: 3 Pages: 33-47
Publisher: Baghdad University جامعة بغداد

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Abstract

The finishing operation of the electrochemical finishing technology (ECF) for tube of steel was investigated In this study. Experimental procedures included qualitative and quantitative analyses for surface roughness and material removal. Qualitative analyses utilized finishing optimization of a specific specimen in various design and operating conditions; value of gap from 0.2 to 10mm, flow rate of electrolytes from 5 to 15liter/min, finishing time from 1 to 4min and the applied voltage from 6 to 12v, to find out the value of surface roughness and material removal at each electrochemical state. From the measured material removal for each process state was used to verify the relationship with finishing time of work piece. Electrochemical finishing proves an effective method to reduce the surface roughness (Ra) from 1.6µm to 0.1µm in 4 min. Finally, the observed relationships were used to predicate the diameter of blank, tool diameter and flow rate by neural network modeling ANN which has inputs defined by the finished hole diameter, surface roughness, and finishing time. Three of hidden layers and their neurons were found by an integration procedure. The design charts observed from this study utilize the designers in predication of diameter for blank and design of electrode.


Article
Evaluation of the Surface Roughness for Three Different Types of Composite Resin Materials Using (Sof–Lex) Finishing and Polishing Systems: A Comparative Study

Author: Sabah A Ismail
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2013 Volume: 13 Issue: 2 Pages: 221-227
Publisher: Mosul University جامعة الموصل

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Abstract

Aim: To evaluate the surface roughness of three different types of light activated composite resin using (Sof-Lex) – polishing system, a profilometer study. Materials and Methods: A total of 30 resin com-posite disks were prepared from three different types of composite resin include 3 – groups. Group I: 10 specimens were prepared from light activated nano hybride (Tetric n – Ceram, Ivoclar – Vivadent – Liechtenstein). Group II: 10 specimens were prepared from light activated microhybride composite resin (Arabesk – Voco, Germany). Group III: 10 specimens were prepared from light activated poly-glas composite resin (Solitaire – 2, Heraeus, Kulzer, Germany). The resin blocks finished and polished using (Sof – Lex) polishing system. The specimens were analyzed for surface roughness using “Pro-filometer”. Results: Tetric n – Ceram composite resin showed the lowest roughness average (0.112 μm) followed by Arabesk composite (0.150 μm), Solitaire – 2 composite resin showed the highest roughness average (0.341 μm). Conclusions: Tetric n– Ceram (nano-hybride) was the best polished composite resin, showed the least roughness average.


Article
Effect of different polishing systems on the surface roughness of full-contour zirconia

Authors: Hussein Muhammed Wajih حسين محمد وجيه --- Adel F. Ibraheem عادل فرحان ابراهيم
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2014 Volume: 26 Issue: 4 Pages: 39-45
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Adjustment of any premature occlusal contact of any zirconia restoration requires its polishing orglazing in order to restore the smoothness of the restoration. The objective of this in vitro study was to evaluate theeffects of different polishing systems and glazing on the surface roughness of full-contour zirconia.Material and methods: Forty disks (diameter: 8 mm, thickness: 6.4 mm) were prepared from pre-sintered fullcontouredzirconia block; they were colored and sintered in a high-temperature furnace at 1500˚C for 8 hours. Thespecimens were then leveled and finished using grinding and polishing machine and adjusted using diamond disk.The specimens were then randomly divided into four groups (n=10), group I involves samples that were polished using(karat diamond polishing set, Vita zahnfabrik, Germany), group II involves samples that were polished with (zirconiapolishing kit, SMEdent, Shanghai, China), group III involves samples that were polished with (OptraFine® diamondpolishing system, Ivoclar Vivadent, Germany), while group IV involves samples that were glazed using glazingmedium (VITA Akzent Glaze AKZ 25, Vita zahnfabrik, Germany). Surface roughness values (Ra) (in μm) of all thespecimens were recorded at each stage of surface treatment of zirconia disks (leveling and finishing, adjustment ofthe samples and polishing / glazing) using surface roughness tester. Statistical analysis was carried out using one-wayANOVA and LSD tests.Results: The results showed that the glazing group recorded the lowest surface roughness mean value, followed by(OptraFine® polishing system), then (zirconia polishing kit) and finally (karat polishing set) which showed the highestmean of surface roughness. For all groups, there was a statistically very high significant difference of (Ra) valuebefore and after adjustment of the samples. Moreover, there was a statistically very high significant difference in (Ra)value when comparing the adjusted samples with the polished and glazed ones. Karat polishing set group showed astatistically highly significant difference with zirconia polishing kit group (P<0.01). Both, karat polishing set and zirconiapolishing kit groups showed a statistically very highly significant difference (P<0.001) with (OptraFine® polishingsystem) and glazing groups. On the other hand, no statistically significant difference was found between glazing and(OptraFine® polishing system) groups (P>0.05).Conclusions: Adjusting full-contour zirconia with diamond bur or disk resulted in a significant increase in (Ra) thatnecessitates its polishing or glazing to restore the surface smoothness. Furthermore, both glazing and OptraFine®polishing system provided the best surface smoothness, so glazing can be substituted with chairside polishing usingOptraFine® polishing system.

إن تعدیل أي إطباق مبكر سواء لتركیبات السیرامیك أو الزركون, یتطلب تلمیعھا أو إعادة تزجیجھا من أجل استعادة النعومة المطلوبة. إن الھدف من ھذه الدراسة المختبریة ھو لتقییمآثار نظم التلمیع المختلفة و التزجیج على خشونة سطح الزركون المعدل.تم تحضیر أربعین عینة من الزركون، تم تلوینھا و طبخھا في فرن ذو درجة حرارة عالیة ( 1500 درجة مئویة لمدة 8 ساعات).بعد ذلك تم تسویة اسطح العینات و صقلھا بواسطة جھازالصقل, و بعدھا تم تعدیل أسطح العینات بواسطة قرصماسي. تم تقسیم العینات بعدھا عشوائیا إلى أربع مجموعات كل مجموعة تحوي عشرة عینات.المجموعة الاولى تم تلمیع أسطحفي المجموعة الثانیة تم تلمیع أسطح العینات بواسطة (طقم التلمیع الخاص بالزركون), المجموعة الثالثة تم تلمیع أسطح عیناتھا ,(Karat العینات فیھا بواسطة (طقم التلمیع الماسيالمجموعة الرابعة تم تزجیج العینات فیھا بمادة تزجیج مناسبة. تم تسجیل قیم خشونة الأسطح (بالمیكرو متر) لجمیع العینات في المراحل ,(Optrafine® بواسطة (طقم التلمیع الماسيANOVA الثلاثة (التسویة والصقل، تعدیل سطح العینات ,تلمیع العینات/ تزجیجھا) بإستخدام جھاز قیاس خشونة السطح (البروفیلومیتر). وقد أجري التحلیل الإحصائي بتطبیق اختبار.LSD احادي الاتجاه و إختبارثم مجموعة (طقم التلمیع الخاصبالزركون), وأخیرا مجموعة (طقم ،(Optrafine® أظھرت مجموعة التزجیج أقل متوسط خشونة لأسطح العینات، تلیھا مجموعة (طقم التلمیع الماسيوالتي أظھرت أعلى متوسط خشونة. للمجموعات الأربع، كان ھناك فروق ذات دلالة إحصائیة عالیة جدا بین متوسط الخشونة قبل تعدیل العینات و متوسط (Karat التلمیع الماسيالخشونة بعد تعدیلھا. أیضا كان ھناك فروق ذات دلالة إحصائیة عالیة جدا في متوسط الخشونة بعد تعدیل العینات و متوسط الخشونة بعد تلمیع- تزجیج العینات. أظھرت مجموعة (طقمو (طقم التلمیع الخاص (Karat وأظھر كل من (طقم التلمیع الماسي .(P < فرق معنوي عالي إحصائیا مع مجموعة (طقم التلمیع الخاص بالزركون) ( 0.01 (Karat التلمیع الماسيبینما لم یظھر ھناك اي فرق معنوي ذات دلالة إحصائیة .(P < و (التزجیج) ( 0.001 (Optrafine® بالزركون) فرق ذات دلالة إحصائیة عالیة جدا مع مجموعتي (طقم التلمیع الماسي.(P= و (التزجیج) ( 0.774 (Optrafine® بین مجموعتي (طقم التلمیع الماسيو كإستنتاج, فإن فان نتائج البحث اشارت الى أن تعدیل سطح الزركون بواسطة قرص او مثقب ماسي أدى إلى زیادة كبیرة في متوسط الخشونة, مما یوجب ضرورة تلمیع سطحو (التزجیج) أفضل نعومة لسطح الزركون مع عدم وجود اي فرق احصائي بین (Optrafine® الزركون أو تزجیجھ لإستعادة نعومة السطح. قدم كل من (طقم التلمیع الماسيمعوضا عن الحاجة لتزجیج تركیب الزركون مع الحصول على (Optrafine® المجموعتین, و بالتالي , من الممكن ان یكون تلمیع سطح تركیب الزركون بواسطة (طقم التلمیع الماسينعومة سطح مشابھة.


Article
Investigation of Material Removal Rate and Surface Roughness for AISI 1015 Steel Rack Gear in Wire EDM Process

Authors: Mostafa Adel Abdullah --- Safaa Kadhim Ghazi --- Mustafa Mohamed
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 12 Part (A) Engineering Pages: 2361-2370
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this work an investigation of the effects of various process parameters of Wire-EDM like Servo Feed (SF), pulse off-time (TOFF), pulse on-time (TON), as inputs impact on surface roughness (Ra) and metal removal rate (MRR) as outputs on steel (AISI 1015) utilizing nine specimens. With servo feed (500, 600 and 700)mm/min, pulse-of time (10,30,50) μsec, pulse on-time (20,25,30) μsec.The characteristics of cutting variables were determined by implementing Taguchi experimental design method. The importance level of the cutting variables for metal removal rate and surface roughnessis determined by implementing the analysis of variance (ANOVA).

Keywords

Taguchi --- ANOVA --- surface roughness --- MRR.

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