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91.
Saleh Ahmed Wasimi 《Water Resources Management》2010,24(12):2991-3015
The approval for a large dam project proposal these days predominantly involves satisfying broadly the criteria of economic
development, social equity, and environmental sustainability. It is justified that the criterion of economic development seeks
full project cost recovery as well as significant contribution to economic growth of a region. Cost–benefit analysis is normally
used as the yardstick for economic development but it has limitations and a better method is warranted. Social equity considerations
should embody the need to address the concerns of all sections in communities to be impacted by a project and involve them
in the decision-making process. The lapse of this aspect in project planning of the past has led, at least as being partly
responsible, to disastrous consequences. Environmental sustainability should seek to ensure that the vital components of the
environment are preserved such that the future generation can use the natural resources to their benefit at least as much
as the current generation. Environmental sustainability is arguably the most contentious criteria among these. The vagueness
in the concept of environmental sustainability and the tendency of the society to err on the safe side have caused many large
dam project proposals not reach their fruition. An attempt is made in this paper to define environmental sustainability in
a more meaningful way from an analytic viewpoint. The case of Traveston Crossing Dam project in southeast Queensland, Australia
is presented as an illustrative example and to evaluate the performance and relevance of the three broad criteria in a real-world
application. The case study is also an example of the fact that environmental awareness can lead to enormous level of socio-political
forces which can create many hurdles to cross by a democratic government. 相似文献
92.
Kadhim Mustafa M. Rheima Ahmed Mahdi Shadhar Mohanad Hatem Abdulnabi Shuaib M. Saleh Zuhra Muter Al Mashhadani Zuhair I. Najm Zainab Mohsen Sarkar A. 《SILICON》2023,15(1):417-424
Silicon - A theoretical research study was conducted into the possibility of using a two-dimensional graphene-like material silicon carbide nano-sheet (2D-SiCNS) as an anode in rechargeable Ca-ion... 相似文献
93.
Analysis of cooling curve to determine the end point of freezing 总被引:1,自引:0,他引:1
M. Shafiur Rahman Nejib Guizani Mohammed Al-Khaseibi Salim Ali Al-Hinai Salha Saleh Al-Maskri Khalid Al-Hamhami 《Food Hydrocolloids》2002,16(6):111
The cooling curve method used for the measurement of freezing point of food is further analyzed to explore whether it can be used to identify the end point of freezing or glass transition. In this method, slope of the cooling curve is determined and plotted as a function of time to identify the end point of freezing (T′m). Initially, the slope is decreased and then reached a minimum value, which is identified as the nucleation of ice. Then the slope is increased until the end point of freezing. The end point of freezing is identified when the slope starts to decrease from its highest value or plateau. Sucrose solutions and starch gels were used to measure its T′m in identifying validity of the proposed method. The measured values of T′m by the proposed method is very close to the literature values. 相似文献
94.
Any refrigerant device consists of several parts, and one of the most significant parts is the expansion device. This expansion device can be classified into several types according to the size of the refrigeration system. The capillary tube is used usually with a small refrigerant system size to reduce the higher pressure in the condenser into the low pressure in the evaporator. In this study, the effect of the capillary tube's diameter and that of the temperature of the condenser and evaporator on the length of such a device has been theoretically studied. Furthermore, a validation between the theoretical analysis and experimental findings from the literature review has been carried out. To achieve the theoretical aspect, MATLAB code has been developed. The results showed that the maximum difference between the theoretical and experimental results regarding temperature and pressure refrigeration is around 5% and 3.4%, respectively. Also, the results depict that the inner diameter and the condenser temperature have an effect on the length of the capillary tube. However, the effect of the inner diameter is higher compared with the condenser temperature. In addition, an equation to predict the length of the capillary tube has been developed with an accuracy of 98%. This equation is created as a function of the capillary tube's diameter and the temperature of the condenser and the evaporator. Moreover, this equation can be used to predict the length of the capillary tube for small refrigeration devices, especially those operating under 10 KW. The findings of this study can help make a mathematical approach used for the design of the capillary tube simpler and easier to apply. 相似文献
95.
Abeer S. Yamany Fathy Abdel-Ghaffar Saleh Al Quraishy Ohoud Al-Amri Heinz Mehlhorn Rewaida Abdel-Gaber 《Microscopy research and technique》2022,85(4):1580-1587
The risk of malaria recurrence increases due to the main vector, Anopheles pharoensis. The physiological age of the mosquito population is needed to expect malaria vector dynamics. The number of completed gonotrophic cycles is of great importance in determining the physiological age of females. A technique has been described that focuses on the number of dilatations remaining in the ovarioles after each oviposition to determine how many blood meals have been taken. At each gonotrophic cycle, the chances of infection of the vectors are repeated. The histological changes that occur immediately in the ovarioles and ovulation itself were studied. Under the influence of the contractions of the ovarian muscles, the eggs begin to move over the distal end of the ovariole into the inner oviduct. The terminal pedicle is markedly dilated near the diameter of the eggs. After the expulsion of the mature eggs, ovariole dilations were found at the point of their development in the terminal pedicle due to the accumulation of nurse cell remnants and follicular epithelium. The results were used to develop epidemiological localization and to evaluate the effectiveness of antimalaria interventions. The ovarian inspection often provides a technique to distinguish nulliparous from parous female anophelines. In addition, this study can provide basic entomological knowledge on the physiological age of mosquitoes by considering the histological changes in the ovaries, which allow the evaluation of vector management strategies in the field. 相似文献
96.
In this paper, a class of the direct methods for discretization of fractional order transfer functions is studied in the sense of stability preservation. The stability boundary curve is exactly determined for these discretization methods. Having this boundary helps us to recognize whether the original system and its discretized model are the same in the sense of stability. Finally, some illustrative examples are presented to evaluate achievements of the paper. 相似文献
97.
98.
H.E. Saleh 《Renewable Energy》2009,34(10):2178-2186
Jojoba methyl ester (JME) has been used as a renewable fuel in numerous studies evaluating its potential use in diesel engines. These studies showed that this fuel is good gas oil substitute but an increase in the nitrogenous oxides emissions was observed at all operating conditions. The aim of this study mainly was to quantify the efficiency of exhaust gas recirculation (EGR) when using JME fuel in a fully instrumented, two-cylinder, naturally aspirated, four-stroke direct injection diesel engine. The tests were carried out in three sections. Firstly, the measured performance and exhaust emissions of the diesel engine operating with diesel fuel and JME at various speeds under full load are determined and compared. Secondly, tests were performed at constant speed with two loads to investigate the EGR effect on engine performance and exhaust emissions including nitrogenous oxides (NOx), carbon monoxide (CO), unburned hydrocarbons (HC) and exhaust gas temperatures. Thirdly, the effect of cooled EGR with high ratio at full load on engine performance and emissions was examined. The results showed that EGR is an effective technique for reducing NOx emissions with JME fuel especially in light-duty diesel engines. With the application of the EGR method, the CO and HC concentration in the engine-out emissions increased. For all operating conditions, a better trade-off between HC, CO and NOx emissions can be attained within a limited EGR rate of 5–15% with very little economy penalty. 相似文献
99.
100.
A. I. Saleh 《The International Journal of Advanced Manufacturing Technology》2013,67(1-4):455-473
Field programmable gate arrays (FPGAs) are designed to implement any logic circuit with the ability to host several independent tasks simultaneously. They inherit reconfigurability from their programmable architecture. However, designs are usually dynamic and the arrival times of tasks may be unknown in advance. Accordingly, FPGA should have the ability to: (1) place incoming tasks at run time, and (2) compact the chip whenever needed. Compaction is a proposed solution to alleviate external fragmentations. It tries to move running tasks closer to each others to free a sufficient area for hosting more tasks. Unfortunately, traditional compaction techniques suffer from internal and external fragmentations. This paper introduces a novel puzzle-based compaction (PBC) technique. PBC is a shape-aware technique that is the first to take the task shape into consideration. Hence, it succeeds not only to eliminate the internal fragmentations but also to minimize the external fragmentations. Moreover, the paper develops a novel formula, which is the first not to estimate, but to exactly calculate the amount of external fragmentations generated by hosting a set of tasks inside the reconfigurable chip. Experimental results have shown that PBC outperforms recent compaction techniques in which the chip utilization has reached 87 %. 相似文献