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- ItemEFFECT OF HORIZONTAL ECCENTRICITY ON THE RESPONSE REDUCTION FACTOR (R)(An-Najah National University, 2025-08-05) Bustami, HayaStructural irregularities significantly affect the seismic performance of buildings. Structures with architectural flaws may endure excessive twisting, differential story displacements, and probable collapse during seismic events. International standards, including ACI and ASCE, lack explicit directives for including the response modification factor (R) in the presence of horizontal eccentricity cases. The study aims to examine the impact of horizontal irregularity on the R factor for Intermediate Moment Resisting Frame (IMRF) structures. The study examines two variables: the number of stories and the amount of eccentricity. The study encompasses structures of 5, 7, 9, 12, and 15 stories, exhibiting eccentricity indicator values that vary from zero for reference specimens to 60% of the building width. SAP2000 is utilized for the analysis and design of buildings, incorporating response spectrum nonlinear analysis for seismic forces in accordance with ASCE standards. Push-over curves are produced to ascertain the correlation between horizontal eccentricity and R-value. Diverse push-over curves are utilized to examine various conditions. This encompasses standard push-over curves with flexural hinges, push-over curves incorporating mixed flexural, shear, and torsion hinges, as well as push-over curves reflecting the influence of bidirectional lateral pressures (push-over modal curves). The results demonstrate that the R-factor for the reference building corresponds with the recorded code value. Moreover, elevated eccentricity levels diminish the R-factor for buildings of identical height. As the elevation of the structure rises, the R-factor diminishes. The R-factor reduction varies from zero for the reference specimens to 25% for a fifteen-story with 60% eccentricity indicator. Utilizing bidirectional push-over curves that integrate integrated flexural, shear, and torsion hinges results in a 30% reduction in R-factors. For the majority of moderately tall structures, the reduction is approximately 15%. The decrease in the R-factor results from the development of plastic hinges on one side of the structure, causing abrupt failure of specific joints before the joints on the opposite side give.
- ItemTHE IMPACT OF CONSTRUCTION CONTRACTS ON PROJECT PERFORMANCE IN WEST BANK: CONFLICT RESOLUTION AS A MEDIATOR(An-Najah National University, 2025-08-21) Abu-Eisheh, Suleiman AbdulghaniThe construction sector in the West Bank plays a crucial role in driving economic development and urban expansion. However, this sector experiences performance-related challenges, including project delays, cost overruns, and quality issues, many of which stem from contract ambiguities and ineffective conflict resolution. Modern project management theory emphasizes the crucial role of well-defined construction contracts and structured conflict resolution processes in enhancing project outcomes. Despite the increasing complexity of construction projects, the West Bank lacks binding legal frameworks. Many stakeholders rely on generic, unmodified templates or avoid professional legal consultation when forming contracts. This has led to persistent disputes and project underperformance. The primary objective of this study is to assess the impact of construction contracts on project performance, with conflict resolution as a mediating variable. A quantitative, explanatory research design was employed using PLS-SEM with Smart-PLS. A hierarchical reflective–reflective model was tested using the disjoint two-stage approach. The questionnaire included 75 indicators across three constructs and was distributed to 130 qualified participants across the West Bank. Seven indicators were removed during the model modification process to ensure acceptable reliability and multicollinearity levels, two due to low outer-loadings, and five due to high VIF values. The results showed that construction contracts significantly influence project performance (β=0.316, t=5.113, p<0.001), and conflict resolution (β=0.487, t=6.820, p<0.001). Conflict resolution also had a significant direct effect on performance (β=0.500, t=8.801, p<0.001), and it partially mediated the relationship between contracts and performance, as supported by the Variance Accounted for (VAF=43.5%), and the significance of the indirect effect (β=0.243, t=5.325, p<0.001). The model exhibited strong internal consistency, convergent and discriminant validity, and fit indices (SRMR=0.044 and GOF=0.537). Descriptive analysis revealed a general weakness in construction contracts across the West Bank, highlighting key areas needing development. The study concluded that strengthening construction contracts and improving conflict resolution enhances project performance in Palestine, and conflict resolution mediates the relationship between contracts and performance. Practically, this study provides a validated framework that guides policymakers and stakeholders in reforming contracts, strengthening the legal enforceability of ADR outcomes, and institutionalizing training programs and sustainable management practices to enhance this sector.
- ItemCo₂MnSi, FULL HEUSLER COMPOUND FOR SOLAR CELL APPLICATIONS(An-Najah National University, 2025-09-03) Najjar, SamerThe simulations for this thesis were performed in COMSOL Multiphysics, which is one of the most commonly used platforms for scientific modeling and analysis. This project proposed a three-layer solar cell design, with particular emphasis on one of the crucial layers, the absorber layer. In this study, was evaluated the performance of a Full Heusler compound (Co₂MnSi) against traditional materials such as silicon and perovskite. During the simulation process, the temperature was held constant at 298 K, and the absorber layer thickness was varied from 100 nm to 700 nm for all three materials to allow for a fear comparison. For all materials, an initial applied voltage of 0-0.55 V led to nearly identical length quantities at first. When the voltage reached above to range 0-1.2 V, performance degradation was detected, but no significant difference was found otherwise. The presented method provides short circuit current density Jsc, open circuit voltage Voc, and fill factor FF for sub-cells measuring current in both forward bias and reverse bias, without compromising overall cell performance. An efficiency as high as 41.41% is achievable with the heusler compound Co2MnSim surpassing the performance of silicon and perovskite-based structures in this regard. In addition, several graphical analyses were obtained (I–V, J-V and P–V characteristics), were conducted to demonstrate the behavior of these three materials under different operating conditions. These results reveal that Co₂MnSi is a good candidate for an advanced absorber material in the next-generation photovoltaic device.
- Itemدور تصميم الخطوط والألوان في تحفيز السلوك الطلابي وتعزيز الأداء الأكاديمي: حالة دراسية المدارس الأساسية في مدينة سلفيت(جامعة النجاح الوطنية, 2025-09-01) رنين أبويعقوبالتصميم الداخلي هي عملية تسعى لخلق فضاء معماري داخلي والاهتمام بكل تفاصيله، وهي تعالج عناصر الفضاء من أرضية وسقف وجدران، من أجل خلق بيئة ملائمة لراحة المتلقي .من خلال هذا البحث سيتم دراسة الدور الذي يلعبه كل من الخطوط والألوان في التصميم الداخلي وما هو مدى التأثيرات السيكولوجية لكل منهما على فئة الطلبة (الأطفال) في المدارس الأساسية في فلسطين، فلابد من الاهتمام بتصميم هذه الفضاءات،نظراً للتأثير الكبير الذي تقوم به البيئة المدرسية وخاصة المرحلة الأساسية بتكوين شخصية الطفل.وتهدف هذه الدراسة لتعرف على الخطوط والألوان التي استخدمت في تصميم الفضاء المعماري داخل المدارس الأساسية في فلسطين (الضفة الغربية) من خلال أخذ حالات دراسية محلية والقيام بعمل زيارات ميدانية وتوزيع استبانة ومن ثم تحليلهما لمعرفة هل تم استخدام الخطوط والألوان المناسبة لنفسية الطفل .كما يسعى البحث إلى التعرف على مفهوم وخصائص ونظريات وفلسفة ودلالات الخطوط والألوان، وكما تم التطرق لأنواع الخطوط والمنظومات اللونية المختلفة، ووظيفة كل منهما بالتصميم الداخلي، وتأثيرات الخطوط والألوان على تصرفات المتلقي وبما يخدم المنتج المعماري، وتم جمع المعلومات المستنبطة من الدراسات الميدانية والاستبانة لتحقيق فهماً أكبر لآلية عمل الخطوط والألوان وكيفية توظيفها بشكل مناسب .من هذا المنطلق جاءت هذه الدراسة لتناقش مشكلة تتمثل في السؤال الاتي : ما مدى توظيف الألوان والخطوط في البيئة التعليمية المدرسية الأساسية في محافظات الضفة الغربية؟ وما هو المعيار النموذجي لاختيار الخطوط والألوان الملائمة في القاعات الدراسية بالمدارس الأساسية؟ تقوم فرضية البحث على "أنه لم يتم توظيف الألوان والخطوط في البيئة التعليمية المدرسية في محافظات الضفة بما يتناسب مع وظيفة الفضاء وراحة الطلبة، وأن هنالك معايير يمكن أخذها في الاعتبار تحقق الاعتبارات السابقة". ولتحليل هذه المشكلة، اعتمدت الدراسة على المنهج العلمي لرصد التأثير السيكولوجي للخطوط والألوان على الفضاء المعماري داخل المدارس الأساسية، حيث تضمن ذلك مسحًا مكثفًا للمؤلفات العلمية والدراسات المنشورة، فضلًا عن مراجعة مواقع الإنترنت المتخصصة، كما استخدمت الدراسة المنهج الوصفي والتحليلي عبر إجراء وصف وتحليل مفصل للتأثيرات الخطية واللونية في عدة مدارس أساسية عالمية. وبناءً على ذلك، تم تطوير مقياس خاص لاستخدام الخطوط والألوان، والذي تم تطبيقه ومضاهاته على مشاريع محلية. توصلت الدراسة إلى نتائج رئيسية، بالإضافة إلى تقديم توصيات مقترحة لتحسين الأبعاد الخطية واللونية وتأثيراتها داخل الفضاءات التعليمية الداخلية.
- ItemSOME PROPERTIES OF FUZZY NORMED LINEAR SPACES AND OPERATORS(An-Najah National University, 2025-09-08) Bitawi, TinaThis thesis shows the development of fuzzy normed spaces starting with classical normed spaces. Also it shows a review of classical spaces as a background that helps in understanding how these ideas change in the fuzzy world, then the thesis moves to show the meaning of fuzzy sets and fuzzy numbers, then moves to define fuzzy normed spaces and fuzzy operators. As you go through this thesis, you will find easy examples using α level sets. It helps in understanding the fuzzy boundedness, continuity, and convergence. The goal is to give a clear mathematical background to work with uncertain data and can be used as for future studies. In addition, this thesis highlights the importance of fuzzy operators and their bound- edness and illustrates how these concepts are advanced in the study of fuzzy func- tional analysis. The discussions here contribute to the understanding of the theory of fuzzy functional analysis, as well as opening possible avenues for applications in data analysis, decision making, and control