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من أجل مستقبل أفضل لأعمال صيانة المباني السكنية في مصر
Get PDFشهدت مصر في الآونة الاخيرة تزايد حالات انهيار العقارات بسبب إهمال جميع أعمال الصيانة واغفال أهمية مهندس الصيانة على الرغم من أنه من أهم المشاركين فى خطوات العملية التصميمية والإنشائية، فهو الذى يقع عليه عبء اختيار المواد وتصميم استخدام المادة وتطبيق المواصفات التنفيذية والقياسية عليها، وكذلك تحديد العمر الافتراضى لكل مادة. إن أعمال الصيانة لأي مبنى تعنى مجموعة التقنيات العلمية والإدارية التي تشمل الإشراف التام على المبنى بعد تنفيذه وطوال عمره الإفتراضى للحفاظ على مكوناته المعمارية والإنشائية والميكانيكية وغيرها ...أو إعادة تأهيله مرة أخرى، بحيث يكون صالحا للاستعمال ويؤدى وظائفه بشكل مرضى. وهناك عوامل كثيرة تؤثر على متطلبات الصيانة كعمر المبنى، طريقة استخدامه، استعمالاته، الشروط البيئية والبنائية، مستوى التشطيب، المتطلبات القانونية، مواد البناء المستعملة ومستوى جودتها قبل الإنشاء وبعده، مستوى الصيانة المطلوبة للمبنى السكنى، وتوفير الدعم والتمويل اللازم لها. ويضاف إلى ذلك التكلفة الباهظة لمكونات أي مبنى سكنى مما يتطلب المحافظة عليها وصيانتها. والمشكلة الحقيقية تكمن في تجاهل أو إغفال أو تأجيل أعمال الصيانة بدافع تقليص مصروفاتها. رغم أن الهدف من الصيانة بأنواعها هو التقليل من الإنفاق المتوقع على المباني السكنية من خلال معرفة وتحديد أعمال الصيانة المطلوبة لكل مبنى سكنى. ومن هنا كان لابد من التعريف بأعمال الصيانة بكافة أنواعها لوضع أسس جديدة لنظام إدارى متكامل مقترح لصيانة المنشآت السكنية بما يتلاءم ويواكب المباني السكنية المصرية، ومن هنا كانت الحاجة الماسة للمعلومات الواضحة عن الصيانة الشاملة بأنواعها المختلفة. والهدف من هذا البحث إلقاء الضوء على أهمية إدارة أعمال الصيانة للمنشآت السكنية وخطورة إهمالها، ومن ثم معالجة جميع السلبيات نتيجة إهمال الصيانة للعقارات السكنية. ولهذا تم عمل دراسة ميدانية لتقييم الوضع الراهن للمباني السكنية لمعرفة الواقع الفعلي لمشكلة إهمال الصيانة وأبعادها ومسبباتها التي تركزت في وجود خلل تشريعي، هندسي، إداري، وإقتصادى. وتم التوصل إلى وضع تصور عملى لاستخدام المادة وتحديد النقاط الحرجة فى المشروع التى تحتاج للدراسة أو أعمال الصيانة المتكررة لزيادة العمر الافتراضى للمادة المستخدمة. وذلك للوصول إلى فكر وأسلوب أمثل للصيانة الوقائية عند التصميم وقبل التنفيذ. بالاضافة الى اقتراح وتوصيف إنشاء نظام إداري متكامل لأعمال صيانة المنشآت السكنية للمساعدة في مواجهة المشاكل القائمة والمحتملة في المستقبل وتقديم الحلول المناسبة لها بمصر
HEMATOLOGICAL PARAMETERS OF LEBANESE AND SYRIAN REFUGEES LIVING IN PROXIMITY OF DEIR KANOUN RAS EL AIN DUMP IN LEBANON
Get PDFAnemia is one of the most common diseases that are associated with pollutants exposure. A complete blood count test (CBC) can determine the presence of abnormal hematological parameters and diagnose many serious preventable disorders including anemia. To assess the associations between exposure to pollutants and hematologic parameters among Lebanese inhabitants and Syrian refugees, who were exposed to toxic fumes emanating from Deir Kanoun Ras El Ain dump, a population-based study involving 679 Lebanese and Syrian Refugees living in the three villages Deir Kanoun, Klayleh and Smaiyeh was carried out. Blood samples were collected in EDTA tubes. CBC tests were performed and differences were statistically analyzed between different villages, sexes, nationalities, and age groups. Many blood parameters showed abnormal levels indicating hematological disorders including anemia, infections, allergy, and inflammation. Similar trends of abnormal CBC parameters were observed among the three villages. The highest percentage of abnormal erythrocyte parameters was found in Klayleh, while for leukocyte parameters, the highest was in Smaiyeh. Significant differences were observed between sexes and nationalities that may be associated with low income, environmental pollution and poor hygiene. This paper investigates and highlights the associations of living in a polluted area and the abnormal trends of CBC parameters. They emphasize the damaging effect of Deir Kanoun Dump on all inhabitants of the surrounding region calling for immediate intervention from the Lebanese government to find solutions
FOREIGN INVESTMENTS IN DISPUTED MARITIME ZONES: MARITIME DISPUTES AS EVENTS OF FORCE MAJEURE IN INTERNATIONAL LAW AND INTERNATIONAL INVESTMENT CONTRACTS
Get PDFSovereign rights in Exclusive economic zones and Continental shelves are functionally limited to the economic exploitation of these zones. Moreover, in the case of disputed maritime zones these sovereign rights are neither exclusive nor necessarily constant. Nevertheless, states are still expected to provide the investments established in these zones the same treatment they should provide in their territories where they exercise full and constant sovereignty. If a host state agrees to the establishment of an investment in a maritime zone that become later contested, do the occurrence of the contestation and the hazards arising from such contestation relief the host state from its contractual and treaty obligations toward the investment by virtue of the force majeure concept. This paper argues that a traditional interpretation of the force majeure concept in respect of investment agreements and contracts, hampers states ability to de-escalate their maritime disputes, diminishes its capacity to conclude delimitation agreements and reduces the promotion of the UNCLOS III as well as its mechanisms for disputes settlement. It proposes a contextualist interpretation of the force majeure concept that is adapted to the exploitation of disputed maritime zones and states obligations under the international law of the sea. First, it examines the concept of force majeure as a doc-trinal hypothesis and its applications in international contracts and international in-vestment agreements. Second, it analyzes the legal act of maritime contestation as a force majeure event according to the possible interpretations of the concept of “force majeure”. Finally, it examines the recurrent legal implications susceptible of arising out of a contestation; provisional orders and unfavorable delimitation and their qualifica-tion as a force majeure event in the realm of investment agreements and contract
ANTIBACTERIAL EFFECT AND PHYTOCHEMICAL ANALYSIS OF THE SHOOT SYSTEM OF RUBUS CANESCENS DC. GROWING IN LEBANON
Get PDFThe misuse of antibiotics followed by improved fitness of resistant strains of infectious microorganisms hindered the efficacy of many known antimicrobial agents, and fueled research for the discovery of novel remedies. The current study aims at assessing the antimicrobial activity and understanding the mechanism of action of Rubus canescens DC. growing wild in Lebanon, as well as qualitatively determining its phytochemical profile. The antibacterial activity, MIC, and MBC of the extracts were evaluated by two-fold dilution. Time-kill curves were plotted to assess the bactericidal activity of the R. canescens DC. extracts against the growth of microorganisms, and TEM images were collected to confirm such effect. Overall, the extracts exhibited good antibacterial activity against MRSA and E. coli but not against S. pneumoniae and K. pneumoniae as determined by measuring the inhibition zones in plate-diffusion assays. TEM images of treated microorganisms revealed that the R. canescens DC. extracts induced irreversible deformations and damage to the cell membranes of the microorganisms leading to the leakage of cytoplasmic components and eventual cell death. Analysis of Time-Kill curves indicated that the extracts induced 100% killing of the test microorganisms within 10-18 h at the respective MBC. Finally, qualitative phytochemical analysis was conducted to decipher the active ingredients in the plant extracts.The current study reports the first data on the antimicrobial activity of different parts of R. canescens DC. Such promising data opens new avenues for broader assessment of the pharmacological profile of the scarcely investigated R. canescens DC
CONCRETE MIX DESIGN USING SIMPLE EQUATIONS
Get PDFThe behaviour of concrete, whether fresh or hardened, depends basically on the behaviour of its components and the relationship between them, therefore, obtaining a concrete with certain properties depends fundamentally on the concrete mix design. Concrete mix design generally includes two main steps: 1-Selection of the main components suitable for the concrete (cement, aggregate, water, and additives); 2-Determination of more economical mix ratios to fulfil the workability, strength and efficiency requirements. Currently, there are many international methods locally approved for mix designs. They are all related to each other, they give relatively the same quantities of the mix components and they are all capable of providing a good concrete mix. It is important to consider that these methods give approximate quantities which should be checked by experimental mixes in order to obtain results suitable for the requirements of the local environment and local materials. The ACI and BS methods are the most commonly used. Both of these methods depend on graphs and standard tables derived from previous research experience and actual concrete production as well as studies of the properties of the materials used. This paper illustrates a new approach for concrete mix design named as: “Double Coating Method”, which is currently used in some research centers in the republic of Poland and was recently applied in the laboratories of the Civil Engineering Departments in the Universities of Tripoli and Benghazi in Libya. This paper describes experiment in which 24 mixtures were used to assess the usefulness of this technique for problem of proportioning concrete mixtures in general
CORROSION OF COATED AND UNCOATED STEEL REINFORCEMENT IN CONCRETE
Get PDFCorrosion of reinforcing steel is the one of the main causes of deterioration in reinforced concrete structure. During the initial stage of corrosion, the steel volume increases. This creates tensile stresses in the concrete, which can eventually lead to cracking, delamination, and spalling. This potential risk of corrosion in a structure is quite unpredictable. Therefore, this paper examines the influence of accelerated corrosion on the bond between concrete and the coated and uncoated steel bars. The bar coating consisted of epoxy rich in zinc. Six concrete mixes were prepared. Three mixes had cement contents of 300, 400 and 500 Kg/m3 and a water cement ratio of 0.4. In the rest of the mixes, cement was replaced with 10% silica fume and the water to binder ratio was 0.5. The reinforcing bars were placed inside concrete cylinders. After curing for 3 days, the specimens were immersed in a 5% NaCl solution for 7 days while a DC current of 5V flowed through them using a portable power supply. Different tests were conducted such as the accelerated corrosion test (ACT), the pull-out tests, compressive strength, and weight loss. The results show that coating the steel bars while lowering the water cement ratio with the addition of silica fume, reduces the effects of corrosion in reinforced concrete specimen
WATERPIPE: A GLOBAL ALARMING PROBLEM
Get PDFWaterpipe popularity has increased significantly in the recent decades to become the major cause of death worldwide. This practice, which is also known as hookah, shisha and Narghile that is based on tobacco burning, increases the percentage of tobacco smokers especially among young people, due to several factors such as the attracting effect of sweetened tobacco, the marketing role and the social acceptance of waterpipe. A literature review was constructed using Pub med as a searching tool to confirm by studies the differences in adverse effects between waterpipe and cigarette by analyzing the toxicant’s levels generated from them, evaluating the smoke volume which is affected by the duration of smoking, the puffing intensity, and investigating the factors which enhance the toxicity of waterpipe such as the type of the hose and charcoal used during smoking practice. In addition, highlighting the misconceptions regarding the protective effect of water bubbling which has been considered to be a filtering factor for removing several toxicants, showing the type of microorganisms which colonize the different parts of waterpipe device and how they can be transmitted between smokers, focusing on their health hazards and their effects on waterpipe smokers. Finally, emphasizing the importance of specific regulatory policies in controlling the widespread of waterpipe preventing its dangerous consequences and saving human lif
CAEE: COMMUNICATION-AWARE, ENERGY-EFFICIENT VM PLACEMENT MODEL FOR MULTI-TIER APPLICATIONS IN LARGE SCALE CLOUD DATA CENTERS
Get PDFthe increasing demand for cloud computing services has led to the adoption of large-scale cloud data centers (DCs) to meet the user’s requirements. Efficiency and managing of such DCs have become a challenging problem. Consequently, energy-efficient solutions to optimize the whole DC energy consumption, optimize the application’s performance and reduce the cloud provider operational cost are crucial and needed. This paper addressed the problem of Virtual Machines (VMs) placement of multi-tier applications to maximize the compute resources utilization, minimize energy consumption, and reduce network traffic inside modern large-scale cloud DCs. The VM placement problem with communication dependencies among the VMs is modeled as an optimization problem. In this context, to solve the proposed problem, that formulated as a variant of a multiple knapsack problem, an adaptive genetic algorithm is implemented to find a near-optimal solution to the NP-complete modeled optimization problem. To validate the efficacy of the proposed model, extensive simulations are conducted using CloudSimSDN simulator. The experimental results validate the usefulness of the proposed model and its effectiveness in reducing DC energy consumption and optimize network traffic inside DC
Antecedents of Career Development Success: Insights into 10 years of Research
Get PDFThis paper intends to review a flow of previous literature on the antecedents of career development success over ten years, from 2008 to 2018. A systematic literature review has been employed to extract the constitution of literature. A total of 41 relevant articles have been extracted from 16 different top ranked journals. Drawing on the literature, a conceptual model is provided as a clear depiction of what has been studied. Specifically, dependent, independents, mediators, and moderators variables are determined. The systematic literature review identifies six main themes; leadership, organizational and individual commitment, talent management, human resources management practices, career management strategy, and learning and development, determining antecedents of career development success. Literature in this area have offered much attention to both of the Exchange Theory and the Social Learning Theory. The paper advances the career development literature by presenting one of the fewest attempt to systematically review antecedent of career development, with a conceptual framework
THE EFFICIENCY OF RAINWATER HARVESTING SYSTEMS IN THE LEBANESE COASTAL ZONE
Get PDFWater conservation is one of the most important trends within sustainable applications in the world today. The global fresh water demand has increased by 1% per year since the 1980s, and it is estimated that it will continue increasing at this rate until 2050. Therefore, utilizing the available rain water has become a vital parameter for most of the world\u27s countries that lie within the water demand red-zone. Lebanon is moving toward the water demand red-zone rapidly, which has prompted the consideration of rain water harvesting (RWH) systems in the last ten years. The variety in precipitation in the different Lebanese climatic zones has made it essential to examine the efficiency of this project in the Coastal Zone in comparison with the actual water demand. This research focuses on (RWH) and the low-requirements of the water filtering process, such as flushing and irrigation water to reduce the effects of the quality and economic factors. The theoretical approach and experimental case studies were applied to obtain a tangible result regarding RWH efficiency in this Lebanese climatic zone. The research determines estimated values for the RWH volume rate per unit area and for each mm of the annual rainfall average, in addition to the area that could be irrigated for each mm of the annual rainfall average per unit area of the catchment surface. The research also determines the aspects that affect the RWH systems efficiency generally and in Lebanese Costal zone specifically. The economical aspects tackled in the research help to estimate approximate cost for RWH overall systems or specific components of RWH systems in Lebanon, which lead to calculate the payback factor of the investment