SUST Journal Systems (Sudan Univ. of Science and Technology)
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7049 AL-Alloy Fatigue Behavior under Black Paint Laser Peening
Get PDFBlack Paint Laser (bPL) peening technique is currently applied to engineering components due to their improvements of fatigue behavior and economic advantages. In the current work, the experimental examinations of bPL peening, which aims to understanding the fatigue behavior of bPL surface treated bars was carried out. The application of bPL was associated with significant extension of fatigue life and strength. This extension is due to compressive residual stresses (CRS) generating from peening process. A series of fully rotating bending fatigue tests was conducted at room temperature using 7049 Aluminum alloy. Improvements in fatigue life and strength for constant and cumulative fatigue were demonstrated. Finally, the fatigue strength of 7049 Aluminum alloy at 107 cycles increased by 53% and cumulative fatigue life improved by factors of 1.55 and 1.787 for Low-high sequence and high-low sequence due to bPL treatment respectivel
Prediction of Banks Financial Distress
Get PDFIn this research we conduct a comprehensive review on the existing literature of
prediction techniques that have been used to assist on prediction of the bank distress.
We categorized the review results on the groups depending on the prediction techniques method,
our categorization started by firstly using time factors of the founded literature, so we mark the
literature founded in the period (1990-2010) as history of prediction techniques, and after this
period until 2013 as recent prediction techniques and then presented the strengths and
weaknesses of both. We came out by the fact that there was no specific type fit with all bank
distress issue although we found that intelligent hybrid techniques considered the most
candidates methods in term of accuracy and reputatio
The Technical Problems Affecting the Performance of the Ground Water Supply Stations in Darfur (Two Case Studies in North Darfur State - Sudan)
Get PDFتهدف هذه الد ا رسة إلي التعرف علي المشاكل الفنية التي تؤدي إلي تدهور محطات المياه الجوفية بولاية
شمال دارفور بشكل عمومي ومناقشة مسبباتها وتأثيرها علي مكونات المحطة كما بحثت الد ا رسة بتركيز عن الحلول التي
بولاية شمال دارفور. أجريت هذه Case Studies تقلل المشاكل في منطقتي لوابد والفاشر المختارتين كحالتين للد ا رسة
27º ( 22 ) و º 00´ E( الد ا رسة علي محطات آبار المياه الجوفية بولاية شمال دارفور التي تنحصر بين خطي طول
13º ( 18 ( تضمنت كل من مدينة الفاشر التي تنحصر بين خط طول º 00´ N( 12 ) و º 00´N) 00 ( وخطى طول ´ E
)25º 53´ E( 13 ( وخط عرض º 51´ N( 25 ( وقرية لوابد التي تقع بين خط طول º 20´ E( 38 ( وخط عرض ´ N
24 (وهي مضمنة ضمن حالة مدينة º 49´ E( 13 ( وخط عرض º 34´ N( وقرية شقرة التي تنحصر بين خط طول
الفاشر) 1(. تم إج ا رء هذه الد ا رسة بجمع المعلومات من الزيا ا رت الميدانية لمحطات آبار المياه الجوفية بمناطق الد ا رسة
المذكورة أعلاه وكذلك المقابلات الشخصية للجيولوجيين والحفارين المسئولين عن عمليات التركيب والصيانة وتم الحصول
علي بعض المعلومات من الم ا رجع والكتب والدوريات والموقع الإلكترونية المتخصصة . توصلت الد ا رسة إلي المشاكل التي
تحول دون الإنتاج الكافي للمياه الجوفية والتي تتمثل في سقوط المعدات )المضخات ، مواسير الإنتاج( وعدم التحكم في
الرمل الذي يسبب تآكل لأنابيب التغليف والمصافي وغيرها وأيضاً من المشاكل إنخفاض وتذبذب الإمداد الكهربائي الذي
يسبب حرق المحركات الكهربائية الموجودة داخل البئر ومشاكل ناتجة عن عدم مطابقة معدات الآبار للموصفات المطلوبة
)مثلاً إختيار المواسير البلاستيكية للمناطق ذات الملوحة العالية لتفادي مشاكل تآكل المواسير وكذلك مطابقة مواصفات
المضخات للآبار من حيث عمق الخ ا زن وغيرها( بالإضافة إلى الخلل في بعض الصهاريج ومكونات المحطات الأخرى.
أوصت الد ا رسة من خلال النتائج التي توصلت إليها بالصيانة الدورية لمحطات المياه الجوفية من قبل مهندسين ذو خبرة
وعمال مهرة ووحدات صيانة مجهزة بصورة جيدة مع ضرورة الإلمام بالجوانب الفنية التي يمكن أن تحدث مشاكل أثناء
الصيانة وأيضاً م ا رعاة مطابقة معدات الآبار لمواصفات المصنع بالإضافة إلى التوصية بنوعية المواد الملائمة لطبيعة
المنطقة
Evaluation and Analysis of Cavitation Phenomenon in Rosieres Power Plant, Sudan, 2011-2012
Get PDFCavitation is one of the serious problems in hydraulic turbines negatively affects their
efficiency and may cause damages. Cavitation is a phenomenon which occurs as a pitting of metallic
surfaces of turbine parts because of the formation of cavities. In this paper, cavitation in Kaplan turbine
unit 2 in Rosieres power plant was studied and analyzed during flood, water restriction and blackout
periods. The general features of cavitation were described and cavitation variables were determined in the
plant. Cavitation indexes and critical cavitation factors were calculated and compared during these three
periods. The results showed that: the turbines were operated within cavitation limit during these periods.
Cavitation index was found to be higher in water restriction, while minimum power and drop of pressure,
which also increase the possibility of cavities were found in flood and blackout
Quality Assessment of Afrotan Tannery Drinking Water Wells
Get PDFAfrotan tannery was established in 1983, in Albageer Industrial Area- Algazeera State - Sudan. It tans about 20000 skins per day. It uses different harmful amounts of chemicals in tanning processes and it discharges these harmful effluents in land near three drinking water wells. The objective of this study is to assess the quality of these wells and to investigate the contamination of the tannery effluents in the drinking water. Three liters of the tannery tap water was collected from a water reservoir which is fed by the above three wells. 24 parameters of Sudanese Standard Specifications for drinking waters and all the tannery effluents which are expected to contaminate the drinking water wells were measured. The results showed that there is no contamination of tannery effluents to the tannery drinking water wells, and all measured parameters were within the permissible levels of Sudanese Standard Specifications for drinking water. The study recommended periodic conduction of such studies in the future and to take the samples directly from each well to investigate any contaminatio
حقييى الأداء انحقهي ن نًظويت ري بانرش ان حًوري في يشروع سهيج انزراػي
No full text- أجريت تجربة حقمية في محمية شرق النيل بمشروع السميت بهدف تقييم أداء ثلاث انظمة ري محوري . تمت معايرة سرعة تمك
الاجهزة مع كمية المياة المتجمعة وكذلك نسبة معامل انتظام توزيع الماء و انتظام توزيع الماء وكفاءة الاضافة. اظهرت النتائج وجود تفاوت في
نسبة معامل انتظام توزيع الماء , عمى الرغم من تشابة الاجهزة المستخدمة في الد ا رسة حيث كانت هنالك زيادة في قيم نسبة معامل انتظام توزيع
الماء 11 % و 03 % لمجهاز 7 و 0 بالتتابع مقارنة مع الجهاز رقم 1 كما اوضحت النتائج تفاوت في نسبة معامل التجانس بان هنالك زيادة
في القيم 3% و 13 % لمجهاز 7 و 0 مقارنة بالجهاز رقم 1 كما اشارة النتائج بان هنالك تفاوت في قيم كفاءة الاضافة حيت اوضحت بان
هنالك زيادة في القيم 72 % و 31 % لمجهاز 7 و 0 مقارنة بالجهاز رقم 1كما تم الحصول عمى تفاوت في أعماق المياه المتجمعة في اوعية
القياس من جهاز لاخ ا ر , نتيجة لارتباطها بقيم نسبة معامل انتظام توزيع الماء . كما أن عدم اج ا رء الصيانة الدورية لبعض الأجهزة أدى إلى انسداد
بعض الرشاشات , مما أثر سمبا فًًي قيم نسبة معامل انتظام توزيع الماء وقيم أعماق المياه المتجمعة في اوعية القياس وأنعدم ربط بعض من
الرشاشات في أماكنها المخصصة أثر سمب اً في قيم أعماق المياه الخارجة ومن ثم عدم انتظامية توزيع المياه وأداء تمك الأنظمة
Determination the Composition of Afrotan Tannery Sludge’s in Sudan
Get PDFAfrotan tannery was established in 1983 in Albageer Industrial Area- Algazeera State - Sudan. It tans about 20000 skins per day and generates high amount of waste water. Beside the tannery, there are three units of waste water treatment. These treatment units precipitate high amounts of sludge in sedimentation tanks of these units. The tannery collects all this sludge, treats by adding Aluminum sulphate, lime and Poly electrolyte respectively, dewaters by pressing by centrifuge machine and fills it in land. The aim of this study is to determine and to investigate the parameters in sludge before treatment (slurry sludge) and after treatment (dewatered sludge). The analysis was carried out by using standards methods for the Examination of Water and Waste Water, Edition 20, (1998). The results showed that the values of BOD, COD, TVS, NH3, NH4, NO3, SO3, SO4, Cl, Fe, Ca, Na, K, Al and Cr in slurry sludge (before treatment) were found to be 33600 mg/l, 56000 mg/l, 96.0%, 196 mg/kg, 238 mg/kg, nil, 0.25 %, 0.624%, 6747.8 mg/l, 16.18 mg/l, 18.421 mg/l, 8.864 mg/l, 10.609 mg/l, 0.00215 mg/l and 13.23 mg/l, respectively. The values of these parameters in treated and dewatered sludge (after treatment) were found to 40000 mg/l, 68000 mg/l, 81.7%, 252 mg/kg, 306 mg/kg, 28 mg/kg, 1.2 %, 1.44 %, 5100.8 mg/l, 4.911 mg/l, 21.328 mg/l, 9.041 mg/l, 8.146 mg/l, 0.00189 mg/l and 5.897 mg/l, respectively. The study recommended that it is important to prevent filling this sludge in the land to avoid soil contamination and also to conduct further studies to use this sludge in agriculture or others purposes
GENETIC ALGORITHM SOLUTION FOR ECONOMIC DISPATCH AT KHARTOUM NORTH POWER STATION
Get PDFin this paper, genetic algorithm (GA) solution to the economic dispatch problem at
Khartoum North Power Station is presented. The study uses GA to perfectly fix the fuel consumption
problem. GA is a highly nominated way to solve such complicated system. The fuel-cost equations for
each generator in the station have been formulated to satisfy specific constrains. The implementation of
the algorithm involves two modules: knowledge module; holds decision making elements and genetic
module, holds the optimization components such as selection, crossover, mutation and number of
generation. The algorithm works through designed procedure from which the global optima solution
reached. The results of the study revealed that the fuel cost reduced by 64005.12 €/year compared with
those obtained from the station
ANTIMICROBIAL ACTIVITY AND MINIMUM INHIBITION
Get PDFThis research studied the Acacia nilotica fruits (named Garad in Sudan) extract as
antimicrobial agent. Samples were well prepared by garbling in powder form, extracted by solvent
solution using acetone, chloroform, ethanol, and methanol, Acacia nilotica (fruit) extract was punched
on the Erechie - coil and a Staphylococcus aureus organism which often found on the wound skin.
The zone area of inhibition in both E. coli and S. aureus, was best found to be determined, methanolic
extract showing the highest activity and more significant to inhibit the organisms compared to the
other solvents herbal extract.The minimum inhibition concentration(MIC) is also determined at
varying concentrations and it is clear that MIC result is good and fall between 40 &100mg/ml for E.
coli , 50 & 100 mg/ml for S. aurous . GC – MS analysis was done for the herbal extracts in order to
confirm the presence of the bioactive component
الحساب الآلي لطول الصف بغرض تقليل التأخير على الموجهات
No full textThe delay experienced by packets on routers, has become a problem and it the first cause, which reduces the effective functioning of the Internet, this delay is due to the significant increase in the length of the queues on routers, the increase in buffer size by manufacturing in order to prevent the packets drops, forgetting that prevent the packet dropping lead to increase the delay, and the drop of the packets itself is important for the TCP protocol, in this paper we developed a new algorithm called the automatic calculation of the length of the queues (auto), the main work for this algorithm is to modify the length of the queue B automatically, according to the equation , where that C is the channel capacity and RTT is the time to send a packet and return Ack, and n is the number of connections probably estimated and not retain any information relating to connections, the difference between this algorithm and Controlling Queue Delay (Codel), is that the Codel algorithm deal with all packets entering to the router, while the new algorithm to estimate the length of the accurate queue, estimates the number of connections in the router probably, the performance of this algorithm has been compared to the performance of the (Codel) in addition to algorithms working in the field of congestion control, such as Drop-Tail and RED and found that the performance of the auto algorithm is always better with respect to congestion that causes Bufferbloat in addition to the preservation of the channel capacity