مقدمة يشهد العالم في الوقت الحاضر اهتماما متزايدا بقضايا البيئة والتنمية المستدامة، حيث ظهر أن نموذج التنمية الحالي أصبح مرتبطا بأسلوب الحياة الاستهلاكي وعدم الترشيد، والذي أدى بدوره إلي أزمات بيئية متفاقمة. ولتحقيق التكامل في استدامة مجتمعات المدن العربية المعاصرة ينبغي تطبيق مفاهيم الاستدامة على مستوى المبنى والبيئة العمرانية. فقد كان الترشيد في الاستخدام فطرة حياتية وسلوك تلقائي ذو مرجعية في المجتمعات العربية ومدن عمارة المسلمين. وقد حث ديننا الإسلامي علي عدم الإسراف والحفاظ على البيئة، وتجانس العمران مع المستعمل في بوتقة متناغمة، والتكامل بين الجانب البيئي والسيكولوجي والسلوكي للإنسان بالإضافة إلى الجانب الروحي والمادي، وهو ما تعاني منه مدننا العربية المعاصرة. ويمثل المسجد احد أهم المنشآت الدينية التي توجب ضرورة تحقيق مفهوم الترشيد بها ومن ثم تحقيق مفهوم الإستدامة. فرضية البحث: إن المسجد هو المكان الذي يتعلم فيه المسلم كل أمور حياته، وإذا كانت عمارة المسجد تراعى مفاهيم الترشيد في الاستهلاك في مرحلة التصميم فإن ذلك سينعكس على كافة أنشطة الإنسان المسلم وبالتالي على المجتمع بالكامل وعلى كافة الأبنية الأخرى. هدف البحث: تأصيل دور وأهمية المساجد في تطبيق مفهوم الترشيد في الاستهلاك بالمدن العربية المعاصرة. منهجية البحث: تحليل واستنباط طرق تطبيق مفاهيم الترشيد في الاستهلاك في عمارة المساجد العربية المعاصرة.

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We present a real-time open source machine vision code that can detect motion of cells/droplets inside microchannels and control flow parameters accordingly. Our code is based on LabView software, which is available in most laboratories and can be downloaded to a palm-size device to carry program capabilities everywhere. We demonstrate code capabilities in controlling flow velocity of red blood cells, differentiating RBC’s from other cells in blood, and in differentiating between osteoblasts and stem cells labeled with different fluorescent dyes.

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Fiber reinforced plastic (FRP) jacketing has emerged as an effective way to retrofit concrete columns in recent years. The existing experimental work on FRP confined concrete column is mainly concentrated on concrete columns under concentric loading. Therefore, this research involves the study of nonlinear finite element analysis of FRP confined square and rectangular R.C. columns under both axial compressive and lateral loads. Lateral load was taken as a ratio of the axial compressive loads "H/ Pc". The effects of the FRP layer number, concrete compressive strength, percentage of main steel, rectangularity of columns and various ratios of lateral loads to centric load on FRP confined concrete columns were investigated theoretically. The results of this work were compared with previous work [1] considered the behavior of square and rectangular columns confined with CFRP under centric loads. All studied columns were modeled using the nonlinear finite element analysis. The main variables studied were the cross-section shape of the column “R”, concrete grade “C”, the percentage of area of the main longitudinal steel “As%” and the number of layers of CFRP sheet “NL”. The FEM results indicated that R.C. columns externally wrapped with CFRP sheet showed a significant improvement in both capacity and ductility.

Fiber reinforced plastic (FRP) jacketing has emerged as an effective way to retrofit concrete columns in recent years. The existing experimental work on FRP confined concrete column is mainly concentrated on concrete columns under concentric loading. Therefore, this research involves the study of nonlinear finite element analysis of FRP confined square and rectangular R.C. columns under both axial compressive and lateral loads. Lateral load was taken as a ratio of the axial compressive loads "H/ Pc". The effects of the FRP layer number, concrete compressive strength, percentage of main steel, rectangularity of columns and various ratios of lateral loads to centric load on FRP confined concrete columns were investigated theoretically. The results of this work were compared with previous work [1] considered the behavior of square and rectangular columns confined with CFRP under centric loads. All studied columns were modeled using the nonlinear finite element analysis. The main variables studied were the cross-section shape of the column "R", concrete grade "C", the percentage of area of the main longitudinal steel "As%" and the number of layers of CFRP sheet "NL". The FEM results indicated that R.C. columns externally wrapped with CFRP sheet showed a significant improvement in both capacity and ductility.

The existing experimental work on FRP confined concrete column is mainly concentrated on concrete columns under co centric loading in recent years. Therefore this research involves the study of nonlinear FE analysis of FRP confined square and rectangular R.C. columns under both axial compressive and lateral loads. Lateral load was taken as a ratio of the axial compressive loads "H/ Pc". The results of this work were compared with previous work (Soghair, H.M. et al. 2004) considered the behavior of square and rectangular columns confined with CFRP under centric loads. All studied columns were modeled using the nonlinear finite element analysis. The main variables studied were the cross-section shape of the column "R", concrete grade "C", the percentage of area of the main longitudinal steel "As%" and the number of layers of CFRP sheet "NE'. The FEM results indicated that R.C. columns externally wrapped with CFRP sheet showed a significant improvement in both capacity and ductility.

Currently, there is no general agreement on a theory describing the response of reinforced concrete members without web reinforcement. Many structural systems are usually performed using empirical or semi-empirical expressions provided by codes of practice that do not consider the influence of many governing parameters. In this paper, a comparison between values of current experimental shear strength and those of various international design approaches like ACI, Canadian, FIB and the method proposed by Sudheer, Zararis ,Zsutty ,Shah ,Bazant and Russo. Eighteen simple span high strength reinforced concrete “HSRC” deep beams without web reinforcement were tested and analyzed under two static point loads at mid-span of the beam to examine the contribution of various parameters on the shear capacity of HSRC beams. The main studied parameters are f‟cu=50 MPa, three values of tension reinforcement-ρ%-(0.73%,1.21% &1.83%) and shear span to effective depth ratio-a/d-( 2,1.5 &1). As a conclusion of this paper, ACI and FIB code provisions for shear in HSC are safe for use with the exception that CSA should be used with care. Despite numerous studies, there is still a need to develop a clear understanding of the shear behavior of HSC beams without web reinforcement. Therefore, this experimental program was arranged to evaluate the shear behavior and to increase the shear database on HSRC deep beams.

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