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Article
Enhanced Performance of FH Detection System Using Adaptive Threshold Level
تحسين أداء منظومة كشف إشارة القفز الترددي باستخدام مستوى عتبة متكيف ذاتيا

Author: Ammar Abdul-Hamed Khader عمار عبد الحميد خضر
Journal: AL Rafdain Engineering Journal مجلة هندسة الرافدين ISSN: 18130526 Year: 2010 Volume: 18 Issue: 5 Pages: 107-122
Publisher: Mosul University جامعة الموصل

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Abstract

AbstractThis work investigates the evaluation performance of detection system for Frequency Hopping (FH) signals based on Fast Fourier Transform (FFT) with proposed decision circuit based on Adaptive Threshold Level (ATL), where the threshold level changes its value automatically without manual intervention depending on the estimated values of (SNR) in the channel, the level will be high when the noise is high and vice versus. A comparison in evaluation performance were made with a conventional mode where the decision circuit based on Manually Change Threshold Level (MCTL) done by the detector according to its observation on sensing the Signal to Noise Ratio (SNR). The results shows that the proposed mode (adaptive) is give best results for probability of detection PD and probability of false alarm PF comparing with the (Manually Change). Also the results of (adaptive) are compared with that theoretical computation and gives a very small error for high noise while vanish for low noise. Keyword: Frequency Hopping, Adaptive Threshold Level, Manually Change Threshold Level

الخلاصةهذا البحث يتناول دراسة تقييم أداء منظومة كشف إشارة القفز الترددي المعتمدة في أساس عملها على طريقة تحويل فورير السريعة FFT والمتبوعة بدائرة اتخاذ قرار مقترحة تعمل على تغيير مستوى العتبة بشكل تلقائي من دون تدخل المستلم وذلك وفقا للتخمين الذاتي المستمر لقيمة الضوضاء المضافة على الإشارة بسبب القناة حيث يرتفع المستوى بارتفاع قيمة الضوضاء وينخفض بانخفاضها. لقد تم فحص وتقييم الأداء مقارنة مع نموذج تقليدي تكون دائرة اتخاذ القرار فيه ذات مستوى عتبة يجب تغييره يدويا من قبل المستلم تبعا لملاحظاته عن تحسس تغير قيمة الضوضاء في القناة. من خلال النتائج العملية تبين أن النموذج الأول المقترح (ذاتي التغيير) أفضل من الثاني (يدوي التغيير) من حيث احتمالية الكشف PD واحتمالية التنبيه الكاذب PF. كما تم مقارنة نتائج النموذج المقترح مع النتائج النظرية وكان الفرق بسيط جدا عند قيمة ضوضاء عالية ويتلاشى الفرق عند الضوضاء المنخفضة.


Article
Threshold sensitivity of taste perception and the role of saliva and Zinc level in some physiological & pathological conditions

Authors: Tahani A. Al-Sandook --- Wasan M. Al-Omary --- Taghreed F. Zaidan
Journal: Journal of the Faculty of Medicine مجلة كلية الطب ISSN: 00419419 Year: 2009 Volume: 51 Issue: 1 Pages: 90-94
Publisher: Baghdad University جامعة بغداد

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Abstract

Summary:
Background: Decreased taste acuity to the four basic tastes is closely related to health problems (diseases & medications), aging, and smoking. This study aimed to determine taste detection and recognition thresholds to the four basic tastes in some physiological and pathological conditions, determine saliva flow rate, serum and saliva zinc levels in these groups.
Objective and Methods: The study includes 218 individuals (35–80) years old divided into six groups; the control, aging (subjects over 60 years), smokers, diabetics, haemodialysis patients and hypertensive patients on chronic use of captopril.The taste detection and recognition thresholds of sweet, salty, sour and bitter tastes, saliva flow rate were determined. Zinc concentration was assessed in serum and saliva spectrophotometricaly.
Results: The results showed a significant increase in the taste detection and recognition thresholds of the four basic tastes of all groups than in the control, except the salty taste thresholds of the haemodialysis group and the salty taste detection threshold of the diabetics.
Saliva flow rates, serum and saliva zinc levels decreased significantly at p<0.001 in study groups as compared to the control group.
Conclusions:The taste acuity was impaired in aged subjects, smokers, diabetics, haemodialysis patients, and hypertensive patients on chronic use of captopril.
Decreased saliva flow rate and saliva zinc concentration could be causative factors for hypogeusia.


Article
Sensorineural Deafness Among Patients with Chronic Renal Failure in Al-kindi Teaching Hospital

Author: Raad Aboud Aloubaide رعد عبود العبيدي
Journal: Al-Kindy College Medical Journal مجلة كلية الطب الكندي ISSN: 18109543 Year: 2011 Volume: 7 Issue: 2 Pages: 137-141
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Patients with chronic kidney disease have different grades of sensorineural deafness . Objective: To study the incidence of sensorineural hearing loss and possible contributing factors in patients with chronic kidney disease. Methods: A total of 100 patients with chronic kidney disease were studied. All of them were males. 92 of them were on regular haemodialysis programme. Only 8 patients were on conservative management the age range of the study patients was 18-40 year patients were divided into three groups according to age. All patients were assessed clinically and were evaluated by audiometry , and analysis was made on bone conduction threshold .The mean follow up period was 28 weeks . Results: 36 patients (36 %) showed sensorineural hearing loss .The incidence of sensorineural deafness was found to increase with the advancing age and duration of chronic kidney disease but not directly proportional to the number of haemodialysis sessions .The number of haemodialysis sessions did not show increase in the degree of sensorineural deafness . Conclusion: Patients with chronic kidney disease have sensorineural deafness of some degree which should be assessed and evaluated to halt its progression.


Article
Watermarking for Relational Database by using Threshold Generator

Authors: Bashar Saadoon Mahdi --- Yossra H. Ali
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2011 Volume: 29 Issue: 1 Pages: 33-43
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Providing ownership on relational database is a crucial issue in todayinternet-based application environments and in many content distributionapplications.This paper provides the effective watermarking technique to protectvaluable numeric relational data from illegal duplications and redistributions aswell as to claim ownership,the robustness of proposed system depending on usingnew hybrid techniques ,first technique MAC(Message Authentication Code) thatused one way hash function SHA1 ,second technique is threshold generator baseon simple combination of odd number of register and by using secret key inproposed system. Detecting the watermark neither requires access to neither theoriginal data nor the watermark. The watermark can be detected even in a smallsubset of a watermarked relation as long as the sample contains some of the marks.The finally stage is the analysis of technique that used, our extensive analysisshows that the proposed technique is robust against various forms of maliciousattacks and updates to the data


Article
The effects of type of tooth and the placement site of electrode on the electrical pulp testing of the anterior teeth

Author: Talal H Al–Salman
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2005 Volume: 5 Issue: 2 Pages: 97-102
Publisher: Mosul University جامعة الموصل

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Abstract

The aim of this study is to evaluate the effect of type ofthe tooth and the placement site of electrode on electrical pulptesting of the anterior teeth. Twenty persons were participatedin this study. The six maxillary and mandibular anteriorteeth were checked to evaluate the response threshold to electricalpulp testing; each tooth was examined at four placementsites on its labial surface, which are the incisal edge, incisalthird, middle third and the cervical third.The results showed that the response threshold of themandibular anterior teeth was lower than that of the maxillaryanteriors. The canines may respond to the electrical stimulusin a highest threshold than the lateral incisors and the centralincisors which had the lowest response threshold. Also, thisstudy showed that the best placement site of electrode was inthe incisal edge of the tooth and the pulp tester reading wasincreased as the electrode moved toward the cervical regionof the tooth.


Article
Speech Enhancement Using Wavelet Transform

Author: Manal Hade
Journal: IRAQI JOURNAL OF COMPUTERS,COMMUNICATION AND CONTROL & SYSTEMS ENGINEERING المجلة العراقية لهندسة الحاسبات والاتصالات والسيطرة والنظم ISSN: 18119212 Year: 2008 Volume: 8 Issue: 1 Pages: 34-40
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Abstract:Speech enhancement is an important proceeding which it can be achieved by estimate the clean speech from noisy speech. The clean speech is corrupted by white Gaussian noise . In this paper, thresholding the wavelet coefficients, that can be done by standard deviation method for each frame by level dependent thresholding using semi soft threshold and soft threshold .The results in this work indicate that using wavelet transform in speech enhancement application provides a good quality (measured in object SNR test) as well as provides other advantages which make it more suitable for some application s such as a split of frequencies and enhancement the speech in real time applications .

الخلاصة:تكمن اهمية معالجات التحسين الصوتي بانها تستطيع ان تتوصل و بواسطة التخمين الى صوت اقرب ما يمكن للصوت الاصلي من صوت ضوضائي ،حيث ان الصوت الاصلي يشوه بضوضاء من نوع Gaussian خلال هذه المعالجة تم استخدام طريقة تقليم عوامل المويجة Thresholding والتي انجزت بواسطة طريقة الانحراف المعياري لكل مقطع Frame باستخدام تقليم لكل مرحلة Level Dependent thresholding حيث تم استخدام نوعين من Threshold هما Soft Threshold و Semi Soft threshold تشير النتائج المحصلة في هذا البحث الى ان استخدام تحويل المويجة في تطبيقات ازالة الضوضاء من الصوت قد اعطى نتائج جيدة تم قياسها بالفحوصات الشيئية وكذلك تعطينا بعض المميزات التي تجعلها ملائمة لبعض التطبيقات مثل فصل ترددات الاشارة وكذلك يمكن استخدام تحويل المويجة في ازالة الضوضاء في الوقت الحقيقي .


Article
Modeling of Temperature-Dependent Absorptivity of Laser-Treated Surface

Authors: R.K. Kadhum --- T.S. Salman --- S.A. Mahmood
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2010 Volume: 6 Issue: 3 Pages: 21-24
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

In this work, we have considered the effect of the various properties on the thermal field, the absorptivity plays a special role, because it controls directly the heat input to the sample, while being itself a function of surface temperature. In order to take this dependence into account, the one-dimensional heat conduction equation was solved for a semi-infinite geometry using variable absorptivity and assuming constant thermal conductivity and thermal diffusivity. It is shown that the surface temperature satisfies an Abel integral equation with an approximate analytical solution that gives a temperature rise at the surface linear with t. Comparison is made between analytical approximate expressions, numerical solutions, previous models and experimental results.


Article
Evaluation of Itching Sensation in Chronic Urticaria

Authors: Thanaa Hussain Al-Hamamy --- Hayder Al-Hamamy --- IsraaFaik Al-Samaraee
Journal: Iraqi Academic Scientific Journal المجلة العراقية للاختصاصات الطبية ISSN: 16088360 Year: 2013 Volume: 12 Issue: 3 Pages: 396-400
Publisher: The Iraqi Borad for Medical Specialization المجلس العراقي للاختصاصات الطبية

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Abstract

ABSTRACT: BACKGROUND: Itching is the main symptom in urticaria and can cause a lot of suffering in chronic urticaria. OBJECTIVE: To measure the itch threshold in patients with chronic urticaria before and after treatment andcompare them with healthy control. PATIENTS AND METHODS: The study was conducted at the department of dermatology, medical city teaching hospital Baghdadin the period from December 2009 to July 2010. A total of 30 patients with chronic urticaria (patientsgroup) and 25 healthy individuals (control group), were included in the study.The age of patients ranged between 21years and 48 years with a mean of 30.96 years ± 6.09 years(standard deviation). In control group the age ranged between 20 years and 45 years with a mean of31.40 years ± 8.39 years (standard deviation). Regarding gender, in the patients group 19 werefemales and 11 were males. While in the control group 14 were females and 11 were males.Electrical skin itch threshold was measured by square wave DC electrical stimulator at 13 points onthe skin surface in patients and compared to the healthy controls. Doxepin was given to patients for 2weeks, the itch threshold was then measured again. The severity of urticaria was also assessed beforeand after treatment. RESULTS: Patients with chronic urticaria had significantly lower threshold than the control subjects .The lowest threshold recorded in patients group was (1.292±0.399) volts in the left cheek, while in control groupthe lowest electrical cutaneous threshold was recorded in the chin (1.89±0.490) volts then left cheek(1.910±0.478). The P-value was significance in all skin spots. The electrical cutaneous thresholdincreased after treatment in all spots tested after treatment. The increase was statistically significantin all tested the skin spots except in the back of the neck and xyphoid point. The total score decreased from 10.8 before treatment with doxepin to 1.5 after treatment. Theindividual parameters also decreased significantly after treatment. There were no significant sideeffects except drowsiness which improved after a few days even with continuation of treatment.CONCLUSION: Electrical skin itch threshold seems to be a simple test that aids in measuring the severity of itching inurticaria and may be used in the evaluation of drugs used for the alleviation of itching in urticaria andother skin diseases


Article
THE D.C AND A.C ELECTRICAL PROPERTIES OF POLYMER FILLED WITH METAL POWDER

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Abstract

In this paper the effect of filler content on D.C and A.C electrical properties of polystyrene filled with copper powders has been investigated. The D.C conductivity of such composites increases suddenly by several order of magnitude at a critical weight concentration. The D.C electrical conductivity changed with increasing of temperature. Also the activation energy change with increasing filler concentration. The dielectric constant, dielectric loss, A.C electrical conductivity are increasing with increasing the concentration of the filler and frequency of applied electrical field.

في هذا البحث تم دراسة تأثير إضافة النحاس على الخواص الكهربائية المستمرة والمتناوبة للبولي ستايرين. أظهرت النتائج إلى أن التوصيلية الكهربائية المستمرة تزداد فجأة عدة مراتب عند التركيز الحرج. كما ان التوصيلية الكهربائية المستمرة تتغير مع زيادة درجة الحرارة . كذلك أن قيم طاقة التنشيط تتغير مع زيادة تركيز النحاس المضاف.ثابت العزل,والفقدان العزلي, والتوصيلية الكهربائية المتناوبة تزداد مع زيادة تركيز النحاس المضاف وتردد المجال الكهربائي المسلط.


Article
Detection of malignant Cases by Segmentation of Cells in Medical Images and Applying Fuzzy Logic Technique
كشف الحالات الخبيثة بواسطة تجزئة الخلايا في الصور الطبية وتطبيق تقنية المنطق الضبابي

Authors: Salim J. Attia سالم جلود عطية --- Ziad M. Abood زياد محمد عبو --- Ibrahim R. Agool ابراهيم رمضان عاكول
Journal: JOURNAL OF THI-QAR SCIENCE مجلة علوم ذي قار ISSN: 19918690 Year: 2013 Volume: 4 Issue: 4 Pages: 71-74
Publisher: Thi-Qar University جامعة ذي قار

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Abstract

The process of detection and segmentation of cells is considered in digital optical images of human breast tissue as important base to diagnose the diseases. The major features of malignancy are related with the cells. It is therefore essential to operate a segmentation of the image, to isolate the cells from the rest of image, i. e., from other tissue components, and from some other undesirable elements of images. The recognition process includes a segmentation algorithm based on an adaptive imaging threshold procedure that is sensitive to local ranges in pixel intensity (minimum-maximum values). The statistical features are extracted from the images of cells like median, mode, mean and standard deviation. Then the fuzzy logic method is applied to detect breast cancer.

اجريت في هذا البحث عملية كشف الخلايا وتجزئتها لصور بصرية رقمية لنسيج الثدي البشري وذلك كاساس مهم لتشخيص الامراض. ان اغلب خصائص الحالة الخبيثة تتعلق بالخلايا، لذا من الضروري ان تجرى عملية فصل الخلايا عن باقي الصورة او من باقي مكونات النسيج اوبعض عناصر الصورة غير المرغوب بها. ان عملية ادراك الصورة هنا تتضمن لوغاريتم التجزئة المستند الى طريقة عتبة التصوير المعدلة والتي تتحسس المديات الموضعية لشدة البكسل (قيم عظمى – صغرى ). استخلصت بعض الصفات الاحصائية لصور الخلايا مثل الوسيط والمنوال والمعدل والانحراف المعياري واعلى تردد، ثم طبق المنطق الضبابي لكشف سرطان الثدي.

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