This paper reports a numerical study of flow behaviors and natural convection heat transfer characteristics in an inclined open-ended square cavity filled with air. The cavity is formed by adiabatic top and bottom walls and partially heated vertical wall facing the opening. Governing equations in vorticity-stream function form are discretized via finite-difference method and are solved numerically by iterative successive under relaxation (SUR) technique. A computer program to solve mathematical model has been developed and written as a code for MATLAB software. Results in the form of streamlines, isotherms, and average Nusselt number, are obtained for a wide range of Rayleigh numbers 103-106 with Prandtl number 0.71 (air) , inclination angles measured from the horizontal direction 0º-60º , dimensionless lengths of the active part 0.4-1 ,and different locations of the thermally active part at the vertical wall. The Results show that heat transfer rate is high when the length of the active part is increased or the active part is located at middle of vertical wall. Further, the heat transfer rate is poor as inclination angle is increased.
Flexible job-shop scheduling problem (FJSP) is one of the instances in flexible manufacturing systems. It is considered as a very complex to control. Hence generating a control system for this problem domain is difficult. FJSP inherits the job-shop scheduling problem characteristics. It has an additional decision level to the sequencing one which allows the operations to be processed on any machine among a set of available machines at a facility. In this article, we present Artificial Fish Swarm Algorithm with Harmony Search for solving the flexible job shop scheduling problem. It is based on the new harmony improvised from results obtained by artificial fish swarm algorithm. This improvised solution is sent to comparison to an overall best
... Show MoreBackground: Obesity is considered an important risk factor for periodontal disease. It has been reported that reactive oxygen species linking both diseases, systemic melatonin supplementation as antioxidant therapy, was addressed as an adjuvant to scaling and root surface debridement (SRP) to enhance the treatment of periodontitis. Objective: To investigate the efficacy of systemic melatonin administration in periodontitis-obese patients as an adjuvant to scaling and root surface debridement (SRP). Methods: A randomized clinical trial was conducted at a dental-specialized center. Eighty subjects were included and allocated into group-I: twenty periodontium-healthy, normal-weight people; group-II: 30 obese patients with stage-III tre
... Show MoreThe research aims to design an electronic program that allows users to assess the possibility of different practices for projects management professional according to the PMBOK methodology)) and using the requirements Data mentioned in the "knowledge and experience in project management Evaluation guide" issued by the professional Institute of project management According to the results of this program will be electronic The possible classification of project management in terms of both (proficiency_ perform tasks) as less than the desired level or within or above average in terms of best practices, and finally a number of recommendations to overcome the possible shortcomings. The most important is the need to enrich the service
... Show MoreOne of the most popular causes for implant infection is dental plaque bacteria. Previous studies have shown the bactericidal effect of CO2 laser irradiation on bacteria associated with soft tissue surrounding the implant materials. No published studies have examined the effect of irradiation by CO2 laser on Streptococcus oralis and Staphylococcus aureus.The aim of this study was to evaluate the bactericidal effect of CO2 laser on bacteria that are causing dental implant infections. This study was carried out on two isolates of bacterial species out of 25 samples, isolated from patients having soft tissue infections around the dental implant. These two pure isolates including Streptococcus oralis and Staphylococcus aureus were identified
... Show MoreBackground: The present in-vitro study was undertaken to evaluate and compare fracture resistance of weakened endodontically treated premolars with class II MOD cavities restored with different bulk fill composite restorations (EverX posterior, Alert, Tetric EvoCeram Bulk Fill, and SDR). The type and mode of fracture were also assessed for all the experimental groups. Materials and Method: Forty-eight human adult maxillary premolar teeth were selected for this study. Standardized extensive class II MOD cavities with endodontic treatment were prepared for all teeth, except those that were saved as intact control. The teeth were divided into six groups of eight teeth each (n=8): (Group 1) intact control group, (Group 2) unrestored teeth with
... Show Moreللشعب العربي ولع عميق و ميل شديد إلى الأسفار و الإنتقال من بلد إلى آخر ، لا تثنيهم عن ذلك صحارى واسعة و لابحار شاسعة أو مشاق عنيفة . و قد توارثوا هذا الميل منذ زمن قديم فأوغلوا في قارة آسيا و أفريقيا و أوربا وغيرها . و شقت سفنهم الخليج العربي و المحيط الهندي و البحر المتوسط و بحار اخرى . و لعل هذا الميل إلى الأسفار و الولع بالاغتراب قد عبًر عن نفسه بصورة أدبية في قصص السندباد و بصورة فعلية برحلة إبن جبير و رحلة إبن
... Show Moreيهدف البحث إلى تقييم الكفاءة الوظيفية لمؤسسات التعليم الأهلي في أداء وظيفتها بمستوى عالٍ لتشبع حاجة سكان المدينة الذين فضّلوا التعليم الأهلي على التعليم داخل المؤسسات الحكومية مما أدى إلى انتشارها، وصولا إلى أهم الآثار المترتبة على ذلك الانتشار إذ نافست فيه مؤسسات التعليم الحكومي، بل وتنافست المؤسسات الأهلية فيما بينها لتقديم أفضل خدمة تعليمية للصراع من أجل البقاء، وتهدف أيضا إلى إظهار الوجه السلبي ا
... Show MoreBackground: Atherosclerosis is well known related to age and certain cardiovascular diseases. Aging is one reason of arteries function deterioration which can cause loss of compliance and plaque accumulation, this effect increases by the presence of certain diseases such as hypertension and diabetes disease. Aim: To investigate the reduction of blood supply to the brain in patients with diabetes and hypertension with age and the role of resistive index in the diagnosis of reduced blood flow. Method: Patients with both diseases diabetic and hypertension were classified according to their age to identify the progression of the disease and factors influencing the carotid artery blood flow. By using ultrasound and standard Doppler techniq
... Show MoreA modification to cascaded single-stage distributed amplifier (CSSDA) design by using active inductor is proposed. This modification is shown to render the amplifier suitable for high gain operation in small on-chip area. Microwave office program simulation of the Novel design approach shows that it has performance compatible with the conventional distributed amplifiers but with smaller area. The CSSDA is suitable for optical and satellite communication systems.