Islamic University of Gaza
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Assessment of Habitants’ Thermal Comfort Through Different Treatments of Flat Rooftops in Residential Buildings
No full textAmong different types of roofs for residential buildings, flat roofs are found to be the most common in the Middle East. Flat roofs are an ancient form mostly used in arid climates and allow the roof space to be used by habitants. However, leaving the rooftop of a high or low building without any treatment against weather fluctuation causes thermal discomfort of the habitants beneath. Rooftops without any other treatment are widely applied in residential building, although habitants strive to find a proper solution based on multiple criteria. This study investigated different alternatives of treatments for flat rooftops in residential buildings against multiple criteria from the case study area of Amman in Jordan. DesignBuilder software for environmental analysis is employed to define the effective rooftop treatment according to the best thermal comfort. It is chosen as it has advantages over other software. This study uses the environmental simulation of five alternative rooftop types in hot arid climate. The five alternatives are rooftop with shed, green rooftop, rooftop with compact insulation, rooftop with tile, and rooftop without any treatment. The criteria used to show the interior spaces thermal comfort by assessment of the thermal performance, heating load, and cooling load in each alternative. Results show that green rooftop achieved the best thermal performance in the interior spaces for the total of heating and cooling loads, but unfortunately the cost of construction and maintenance is too high. However, the second alternative was rooftop with compact insulation with less construction cost, then rooftop with tile. The rooftop with shed showed the highest thermal efficiency only in summer.Among different types of roofs for residential buildings, flat roofs are found to be the most common in the Middle East. Flat roofs are an ancient form mostly used in arid climates and allow the roof space to be used by habitants. However, leaving the rooftop of a high or low building without any treatment against weather fluctuation causes thermal discomfort of the habitants beneath. Rooftops without any other treatment are widely applied in residential building, although habitants strive to find a proper solution based on multiple criteria. This study investigated different alternatives of treatments for flat rooftops in residential buildings against multiple criteria from the case study area of Amman in Jordan. DesignBuilder software for environmental analysis is employed to define the effective rooftop treatment according to the best thermal comfort. It is chosen as it has advantages over other software. This study uses the environmental simulation of five alternative rooftop types in hot arid climate. The five alternatives are rooftop with shed, green rooftop, rooftop with compact insulation, rooftop with tile, and rooftop without any treatment. The criteria used to show the interior spaces thermal comfort by assessment of the thermal performance, heating load, and cooling load in each alternative. Results show that green rooftop achieved the best thermal performance in the interior spaces for the total of heating and cooling loads, but unfortunately the cost of construction and maintenance is too high. However, the second alternative was rooftop with compact insulation with less construction cost, then rooftop with tile. The rooftop with shed showed the highest thermal efficiency only in summer
أثر برنامج الاستقصاء بالفلسفة لتنمية المشاركة الأكاديمية لدى طلبة المرحلة الثانوية في المدارس العربية بماليزيا.
No full textThis study aimed to identify the effect of a philosophical inquiry program in improving Academic participation among secondary graders in Malaysia Arabic School. Quasi-experimental approach was followed in this study. To achieve the study aim, the tool of the study were a philosophical inquiry (PI) and an academic participation questionnaire. The sample of the study was Twelfth graders in Saudi Arabia Schools in Kalu Lampour who were 39 students. The results of the study showed that there were statistically significant differences between the mean scores of the secondary graders in improving Academic participation in favor of the post application of the tools.This study aimed to identify the effect of a philosophical inquiry program in improving Academic participation among secondary graders in Malaysia Arabic School. Quasi-experimental approach was followed in this study. To achieve the study aim, the tool of the study were a philosophical inquiry (PI) and an academic participation questionnaire. The sample of the study was Twelfth graders in Saudi Arabia Schools in Kalu Lampour who were 39 students. The results of the study showed that there were statistically significant differences between the mean scores of the secondary graders in improving Academic participation in favor of the post application of the tools
اكتشاب مرض كوفيد-19 في صور الاشعة باستخدام الشبكات العصبية
No full textBased on the best published research from Stanford University, the CheXNet algorithm was developed to diagnose and detect pneumonia from chest X-rays. To achieve better performance than experienced radiologists from the same university, simple changes were made to the algorithm to diagnose 14 pathological condition in the chest X-ray with a performance that exceeds all Previously developed deep learning [1]. In this paper, we experimented with applying a convolutional neural networks (CNN) algorithm in a similar way to the mechanism of work in CheXNet algorithm by using a dataset of 550 Chest X-ray images collected from Kaggle website, some of them are infected with Covid-19 virus. We had an acceptable prediction accuracy of 89.7% which is closed to the results of CheXNet algorithm.بناءً على أفضل الأبحاث المنشورة من جامعة ستانفورد، تم تطوير خوارزمية CheXNet لتشخيص واكتشاف الالتهاب الرئوي من الأشعة السينية للصدر. ولتحقيق أداء أفضل من أخصائيي الأشعة ذوي الخبرة من نفس الجامعة، تم إجراء تغييرات بسيطة على الخوارزمية لتشخيص 14 حالة مرضية في تصوير الصدر بالأشعة السينية بأداء يتجاوز كل التعلم العميق المطور سابقًا. في هذا البحث، قمنا بتطبيق خوارزمية الشبكات العصبية الالتفافية (CNN) بطريقة مشابهة لآلية العمل في خوارزمية CheXNet باستخدام قاعدة بيانات مكونة من 550 صورة أشعة للصدر تم جمعها من موقع Kaggle، بعضها مصاب بفيروس Covid-19. حصلنا على دقة تنبؤ مقبولة بنسبة 89.7٪ وهي قريبة من نتائج خوارزمية CheXNet
الوعي المجتمعي لسكان قطاع غزة في التعامل مع جائحة فيروس كرونا المستجد (كوفيد- 19
No full textThe study aimed to measure the level of societal awareness of its different dimensions (health, social, media, and consumer) for the people of the Gaza Strip in dealing with the Corona virus pandemic (Covid-19). The study was applied a simple random sample of the population of the Gaza Strip who have electronic accounts and their number (710), the results of the study found that the highest level of societal awareness of the population of the Gaza Strip in dealing with the pandemic of the Corona virus is in the social dimension, followed by the health dimension, then the consumer, and the last media dimension, and the study also found statistically significant differences at the level of (α ≤ 0.05) In the level of societal awareness among the study sample in dealing with the pandemic of the Corona virus attributed to the gender variable, in favor of females, and also differences attributed to the age variable in favor of those with age (50 years or more), while the study did not find statistically significant differences at the level of (α ≤ 0.05) in The response of the study sample to the level of societal awareness in dealing with the Corona virus pandemic is due to the variable of the educational level.هـدفت الدراسـة إلى قيـاس مسـتوى الـوعي المجتمعي بأبعاده المختلفـة (الصـحي، الاجتمـاعي، الإعلامـي، الاسـتهلاكي) لسـكان قطـاع غـزة في التعامـل مـع جائحـة فـيروس كوفيـد- 19 ،(تم تطبيـق الدراسـة علـى عينـة قصـدية غـير احتماليـة مـن سـكان قطـاع غـزة ممـن لـديهم حسابات إلكترونيـة وعـددهم (710 ،(توصـلت نتـائج الدراسـة إلى أن أعلـى مسـتوى للـوعي المجتمعي لسـكان قطـاع غـزة في التعامـل مـع جائحـة فـيروس كـوروʭ تمثـل في البعـد الاجتمـاعي، يليه البعد الصـحي، ثم الاسـتهلاكي وأخـير البعـد الإعلامي كما وجـدت الدراسـة فـروق ذات دلالة إحصائية عند مستوى (α ≥05.0 (في مسـتوى الـوعي المجتمعي لـدى عينـة الدراسـة في التعامـل مـع جائحـة فـيروس كورونا لمتغـير الجـنس، لصـالح الاناث، وأيضـا فـروق تعـزى لمتغـير السـن لصـالح الفئـة (50 سـنة فـأكثر)، بينمـا لم تجـد الدراسـة فروقـا ذات دلالـة إحصـائية عند مستوى (α ≥05.0 (في استجابة عينـة الدراسـة لمسـتوى الـوعي المجتمعي في التعامـل مـع الجائحة تعزى لمتغير المستوى التعليمي. الكلمات المفتاحية: الوعي المجتمعي، قطاع غزة، جائحة كرونا كوفيد-19
Effect of using mineral admixtures and ceramic wastes as coarse aggregates on properties of ultrahigh-performance concrete
No full textRecent advancements in recycling have transformed nonrenewable resources into partially renewable resources. In line with these advancements, the application of wastes, including ceramics, as substitute aggregate materials for construction has elicited considerable research interest. Ceramic waste aggregates can be used to address complex problems, such as the shortage of materials in construction sites, and reduce environmental wastes. This study aims to investigate the effectiveness of replacing silica fume (SF) and metakaolin (MK) with cement to improve ultrahigh-performance concrete (UHPC) prepared using ceramic wastes as coarse aggregates. Eleven UHPC mixes with 10%, 20% and 30% proportions of either SF or MK were designed. The fresh, physical, mechanical and microstructure properties of these mixes were evaluated, and test results showed that replacing cement with either SF or MK can improve the mechanical and physical properties of UHPC. The use of this waste as construction material will yield substantial technical, economic and environmental benefits, particularly from the perspective of sustainable development. The results showed that replacing SF or MK is effective in improving the strength of UHPC, particularly when the SiO2/CaO ratio was increased to 2.98. The 28-day compressive strength of UHPC with SF increased from 133.1 MPa to 146.6 MPa due to the improved microstructure and denser matrix.Recent advancements in recycling have transformed nonrenewable resources into partially renewable resources. In line with these advancements, the application of wastes, including ceramics, as substitute aggregate materials for construction has elicited considerable research interest. Ceramic waste aggregates can be used to address complex problems, such as the shortage of materials in construction sites, and reduce environmental wastes. This study aims to investigate the effectiveness of replacing silica fume (SF) and metakaolin (MK) with cement to improve ultrahigh-performance concrete (UHPC) prepared using ceramic wastes as coarse aggregates. Eleven UHPC mixes with 10%, 20% and 30% proportions of either SF or MK were designed. The fresh, physical, mechanical and microstructure properties of these mixes were evaluated, and test results showed that replacing cement with either SF or MK can improve the mechanical and physical properties of UHPC. The use of this waste as construction material will yield substantial technical, economic and environmental benefits, particularly from the perspective of sustainable development. The results showed that replacing SF or MK is effective in improving the strength of UHPC, particularly when the SiO2/CaO ratio was increased to 2.98. The 28-day compressive strength of UHPC with SF increased from 133.1 MPa to 146.6 MPa due to the improved microstructure and denser matrix
Project Manager Interventions in Occupational Health and Safety During the Pre-construction Phase in the Gaza Strip
No full textBackground:
Construction industry is classified as one of the most dangerous industries, where workers are exposed to accidents and risks.
Objective:
This study inspected the role of project manager in promoting Occupational Health and Safety (OHS) during the pre-construction phase in the construction projects in the Gaza Strip. Previous studies were reviewed in order to extract the impact of inadequate health and safety interventions in the construction projects throughout the world, and their applicability in the Gaza Strip was determined.
Methods:
This was achieved through a pilot study and a draft questionnaire. The questionnaire was developed in order to assess and evaluate the perception of project managers on the extent of their roles in promoting health and safety in the pre-construction phase. The sample size was 101, out of which, 77 completed questionnaires were returned by the respondents.
Results:
The study revealed that two project parameters, mainly affected by inadequate health and safety interventions, were quality and labour productivity. The main stage during which a project manager played a significant role in promoting health and safety was the planning stage, with “identifying specific safety issues from prior experience” being the highest sub-factor, which was followed by the designing stage, with “plan works at the design phase through a time schedule, citing the duration of processes, divided into steps and any process priority” being the highest sub-factor.
Conclusion:
Finally, there was the tendering stage, with “make ensure that facilities are provided on site for first aid and emergency medical treatment in the event of an accident” being the highest sub-factor. The results of this study show great awareness of a project manager in promoting health and safety in the pre-construction phase.Background:
Construction industry is classified as one of the most dangerous industries, where workers are exposed to accidents and risks.
Objective:
This study inspected the role of project manager in promoting Occupational Health and Safety (OHS) during the pre-construction phase in the construction projects in the Gaza Strip. Previous studies were reviewed in order to extract the impact of inadequate health and safety interventions in the construction projects throughout the world, and their applicability in the Gaza Strip was determined.
Methods:
This was achieved through a pilot study and a draft questionnaire. The questionnaire was developed in order to assess and evaluate the perception of project managers on the extent of their roles in promoting health and safety in the pre-construction phase. The sample size was 101, out of which, 77 completed questionnaires were returned by the respondents.
Results:
The study revealed that two project parameters, mainly affected by inadequate health and safety interventions, were quality and labour productivity. The main stage during which a project manager played a significant role in promoting health and safety was the planning stage, with “identifying specific safety issues from prior experience” being the highest sub-factor, which was followed by the designing stage, with “plan works at the design phase through a time schedule, citing the duration of processes, divided into steps and any process priority” being the highest sub-factor.
Conclusion:
Finally, there was the tendering stage, with “make ensure that facilities are provided on site for first aid and emergency medical treatment in the event of an accident” being the highest sub-factor. The results of this study show great awareness of a project manager in promoting health and safety in the pre-construction phase
Using safety system during the design phase to minimize waste in construction projects
No full textAchieving construction projects (CPs) with minimal waste requires not only good construction planning, but also effective management for safety and waste of resources through the project cycle. The aim of this paper is to identify and rank safety factors (SF) during the design phase (DPh) of a project that have positive effects in minimizing waste (cost, time and materials) during its construction. Data and information was gathered from available literature, structured interviews, and questionnaire conducted for 111 randomly selected construction organizations. Triangulation method to enhance the validity and reliability of the study findings was used. The research revealed 18 important SF that had positive effects on minimizing waste in CPs during the DPh. The five most important SF that should be considered to minimise waste are: capabilities and behaviour of the design team in the safety field, appropriateness of quantities and specifications for safety system (SS), appropriateness of foundation system for SS, appropriate public and special conditions for SS and appropriate electrical design for SS. The best linear model was developed on the basis of the importance index of the identified factors. A model was developed to minimize waste in CPs by using SS during the DPh. It is recommended that adequate attention must be given to safety criteria during DPh to minimize resources waste.Achieving construction projects (CPs) with minimal waste requires not only good construction planning, but also effective management for safety and waste of resources through the project cycle. The aim of this paper is to identify and rank safety factors (SF) during the design phase (DPh) of a project that have positive effects in minimizing waste (cost, time and materials) during its construction. Data and information was gathered from available literature, structured interviews, and questionnaire conducted for 111 randomly selected construction organizations. Triangulation method to enhance the validity and reliability of the study findings was used. The research revealed 18 important SF that had positive effects on minimizing waste in CPs during the DPh. The five most important SF that should be considered to minimise waste are: capabilities and behaviour of the design team in the safety field, appropriateness of quantities and specifications for safety system (SS), appropriateness of foundation system for SS, appropriate public and special conditions for SS and appropriate electrical design for SS. The best linear model was developed on the basis of the importance index of the identified factors. A model was developed to minimize waste in CPs by using SS during the DPh. It is recommended that adequate attention must be given to safety criteria during DPh to minimize resources waste
Flexural performance of reinforced concrete beams strengthened with self-compacting concrete jacketing and steel welded wire mesh
No full textReinforced Concrete (RC) beam is a paramount structural member for sustaining loads. As result, finding an appropriate strengthening technique is necessary not only for maintaining the safety of the structures but also for achieving the life span requirements. This paper provided an analytical inspection for experimental work of RC beams strengthened with Self-compacting concrete (SCC) and galvanized steel welded wire mesh (SWM) as reinforcement in flexural. As for practical work, the test program included eighteen small-scale beams. All beams were subjected to monotonically loading rate until failure on three control beams, on four monolithic casted control beams and eleven strengthened beams. The strengthened beams were categorized into two groups A and B based on test variables, namely, the SWM properties and the bonding technique. Based on achieved test results, this strengthening technique improved the flexural capacity of strengthened beams significantly. Simplified structural design for predicting the flexural strength and deflection was introduced in this paper at yielding and at the ultimate stages. The comparison was conducted between tested experimental results and the theoretical analysis results. This analysis was performed based on the basis of flexural theory and also reasonable consistent between experiment test results and calculated values was gained at the ultimate and yield stage as well as the derived formulas can be used in real-world strengthening applications.Reinforced Concrete (RC) beam is a paramount structural member for sustaining loads. As result, finding an appropriate strengthening technique is necessary not only for maintaining the safety of the structures but also for achieving the life span requirements. This paper provided an analytical inspection for experimental work of RC beams strengthened with Self-compacting concrete (SCC) and galvanized steel welded wire mesh (SWM) as reinforcement in flexural. As for practical work, the test program included eighteen small-scale beams. All beams were subjected to monotonically loading rate until failure on three control beams, on four monolithic casted control beams and eleven strengthened beams. The strengthened beams were categorized into two groups A and B based on test variables, namely, the SWM properties and the bonding technique. Based on achieved test results, this strengthening technique improved the flexural capacity of strengthened beams significantly. Simplified structural design for predicting the flexural strength and deflection was introduced in this paper at yielding and at the ultimate stages. The comparison was conducted between tested experimental results and the theoretical analysis results. This analysis was performed based on the basis of flexural theory and also reasonable consistent between experiment test results and calculated values was gained at the ultimate and yield stage as well as the derived formulas can be used in real-world strengthening applications
Stability of glassy concrete under elevated temperatures
No full textThe effects of elevated temperatures on concrete containing glass waste are investigated. Addition of 15% waste glass powder by weight of cement is performed to obtain glassy concrete (GC). This study provides several recommendations to enhance construction work and services by using glass waste and explores ways to increase durability for improved construction performance and to meet recycling goals. This experimental work investigates the residual physicomechanical properties of GC and normal concrete (NC) after being subjected to elevated temperatures ranging from 250 to 900 °C. Concrete specimens are subjected to temperatures of 250, 500, 750 and 900 °C with an exposure duration of 1 h. Results show that GC is less sensitive to elevated temperatures compared with NC and exhibits excellent stability at about 900 °C. The GC mixtures have higher flexural strength than compressive strength (50% and 20%, respectively).The effects of elevated temperatures on concrete containing glass waste are investigated. Addition of 15% waste glass powder by weight of cement is performed to obtain glassy concrete (GC). This study provides several recommendations to enhance construction work and services by using glass waste and explores ways to increase durability for improved construction performance and to meet recycling goals. This experimental work investigates the residual physicomechanical properties of GC and normal concrete (NC) after being subjected to elevated temperatures ranging from 250 to 900 °C. Concrete specimens are subjected to temperatures of 250, 500, 750 and 900 °C with an exposure duration of 1 h. Results show that GC is less sensitive to elevated temperatures compared with NC and exhibits excellent stability at about 900 °C. The GC mixtures have higher flexural strength than compressive strength (50% and 20%, respectively)
إعراض المدعو وفقه مواجهته في ضوء السنة النبوية
Get PDFThe path of calling to God Almighty is a well-defined path, straight in direction, but it is punctuated by many challenges and obstacles, including: that the caller may make a commendable effort in his call, but does not find the desired response and the expected and expected interaction from the invited, so signs of apathy appear on him His activity is signs of retreat, and the situation may lead him to stop calling in part or completely, and we wanted in this research to shed light on this challenge and the jurisprudence of confronting it through the Sunnah of the Prophet, peace and blessings of God be upon him, and his fragrant biography. Sunnah".إنّ طريق الدعوة إلى الله تعالى طريق واضحة المعالم، مستقيمة الوجهة، إلا أنَّه يتخللها العديد من التحديات والعقبات، من ذلك: أن الداعي قد يبذل جهدًا مشكورًا في دعوته، ولكن لا يجد الاستجابة المرجوة والتفاعل المتوقع والمأمول من المدعوين، فتبدو عليه علامات الفتور وتظهر على نشاطه أمارات التراجع، وقد يصل به الحال إلى التوقف عن الدعوة جزئيًا أو كليًا، وقد أردنا في هذا البحث أن نسلط الضوء على هذا التحدي وفقه مواجهته من خلال سنة النبي صلى الله عليه وسلم وسيرته العطرة، فكان بعنوان: "إعراض المدعو وفقه مواجهته في ضوء السنة النبوية"