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排序方式: 共有138条查询结果,搜索用时 15 毫秒
1.
Governance and Climate Vulnerability Index 总被引:1,自引:1,他引:0
Water resources in the Middle East are under enormous stress, due to an increase in population growth and the extensive use of water resources, which exceeds the water demand in this regional bloc. Moreover, climatic changes pose another dimension of stress on water resources; these changes have significant environmental, social, and economic effects. In fact, the governance of these countries has the tendency of increasing this stress or decreasing it, depending on its performance and efficiency in applying policies, legislation and managerial plans towards decreasing the poverty and the vulnerability of the countries specially those suffering from poverty. In this paper, the vulnerability of five countries-Israel, Jordan, Lebanon, Palestine and Syria??will be assessed based on the extent of climate changes and the type of climate governance and their effects on water resources. This paper will introduce a new index, which will be called the Governance and Climate Vulnerability Index (GCVI). The index will measure the vulnerability of each country vis-à-vis water-related issues, while taking into account governance and climatic indicators. The vulnerability of these countries will also be ranked, for purposes of comparison. This paper concludes with the recommendation for governments to develop appropriate water resources management and to improve their environmental policies, including raising awareness on multiple levels. These strategies are expected to lead to decreased vulnerability to climatic changes. 相似文献
2.
Wireless Networks - This paper studies enhancing non-orthogonal multiple access (NOMA) spectral efficiency (SE) through optimizing the assigned power to each NOMA user depending on their channel... 相似文献
3.
Nawaf N. Hamadneh Waqar A. Khan Waqar Ashraf Samer H. Atawneh Ilyas Khan Bandar N. Hamadneh 《计算机、材料和连续体(英文)》2021,66(3):2787-2796
In this study, we have proposed an artificial neural network (ANN) model to estimate and forecast the number of confirmed and recovered cases of COVID-19 in the upcoming days until September 17, 2020. The proposed model is based on the existing data (training data) published in the Saudi Arabia Coronavirus disease (COVID-19) situation—Demographics. The Prey-Predator algorithm is employed for the training. Multilayer perceptron neural network (MLPNN) is used in this study. To improve the performance of MLPNN, we determined the parameters of MLPNN using the prey-predator algorithm (PPA). The proposed model is called the MLPNN–PPA. The performance of the proposed model has been analyzed by the root mean squared error (RMSE) function, and correlation coefficient (R). Furthermore, we tested the proposed model using other existing data recorded in Saudi Arabia (testing data). It is demonstrated that the MLPNN-PPA model has the highest performance in predicting the number of infected and recovering in Saudi Arabia. The results reveal that the number of infected persons will increase in the coming days and become a minimum of 9789. The number of recoveries will be 2000 to 4000 per day. 相似文献
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Ai Amy L.; Seymour E Mitchell; Tice Terrence N.; Kronfol Ziad; Bolling Steven F. 《Canadian Metallurgical Quarterly》2009,1(2):112
Spiritual struggle appeared consistently to predict poor health outcomes, including mortality. Despite surging interest in the health benefits of religion and spirituality, the health hassle of existential conflicts and proinflammatory cytokines as a potential physiological mechanism has been overlooked. Based on psychological and theological assumptions, we argue for the universal nature of spiritual struggle, a crisis-related existential conflict, and for investigating its physiological influence as essential to understanding human nature. Increased levels of inflammatory cytokines such as interleukin-6 (IL-6) have been linked with adverse health outcomes and negative emotions. This study thus examined spiritual struggle related to plasma IL-6 in 235 adult patients undergoing cardiac surgery, along with positive religious coping, general coping, and optimism, controlling for standardized clinical medical indicators. Multiple regression analysis, following a preplanned sequence, showed that spiritual struggle (p = .011), behavioral coping (p = .013) were positively associated with excess plasma IL-6, controlling for medical correlates (e.g., left ventricular ejection fraction). We conclude that spiritual struggle, indicating the crisis in an existential relation, and behavioral coping strategies are associated with elevated pre-operative plasma IL-6. The interdisciplinary implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
Nawaf Labban Mounir Iskandar Jeffrey A. Platt Carl J. Andres John A. Levon Suteera Hovijitra 《Journal of Adhesion Science and Technology》2018,32(5):516-526
The aim of the study was to assess the effect of delayed photo-initiation on the polymerization contraction stress (PCS) and degree of conversion (DC) of a dual-cure resin-luting agent. Thirty-five disk (6 mm × 1 mm) samples (n = 10 each group) of dual cure resin luting agent for PCS assessment were fabricated and polymerized using two illuminated quartz rods. Based on the delay in photo-initiation, 30 disks were divided among six groups [group A-0 min (min) delay, group B-2 min, group C-4 min, group D-6 min, group E-8 min and group F-10 min]. A non-photoinitiated group (group G – chemical cure – n = 5) was included as control. The PCS for all specimens was assessed using a Tensometer. For DC evaluation thirty-five specimens were divided into seven groups with delays in photo-initiation (group H-0 min, group I-2 min, group J-4 min, group K-6 min, group L-8 min and group M-10 min, group N-chemical cure). DC was assessed using attenuated total reflectance spectroscopic technique. Statistical comparison among groups was performed using analysis of variance (α = 0.05). The maximum and minimum PCS and DC values with delayed photo-initiation was observed in group-C (3.34 MPa) & group-F (2.44 MPa); and group-M (0.78 MPa) and group-H (0.55 MPa) respectively. Chemically cured samples showed the least PCS (group-G, 1.94) and DC (group-N, 0.53) values in their respective categories. PCS significantly decreased with delayed photo-initiation. A significant increase in DC was noticed when photo-initiation was delayed in the dual cure resin luting agent. 相似文献
9.
Ziad Damaj Aude Naveau Laurent Dupont Eric Hénon Guillaume Rogez Emmanuel Guillon 《Inorganic chemistry communications》2009,12(1):17-20
A solid CoII complex with l-proline as ligand was synthesized and fully characterized using spectroscopic studies, magnetic data, and DFT calculations. Dioxygen scavenging properties were investigated by UV/Vis spectroscopy and oxymetry techniques. The Co-proline system presented very interesting properties in matter of oxygen absorption capacity both in solution and incorporated in a polymer matrix. 相似文献
10.
Ziad Mansour Mohd Raihan Taha Zamri Chik 《Bulletin of Engineering Geology and the Environment》2009,68(1):97-106
Problems have occurred with dykes constructed on the Lisan Marl to retain brine pumped from the Dead Sea, which is chemically
processed to produce potash. In this study the engineering behavior, collapse potential and compressibility of the Lisan Marl
were assessed by undertaking laboratory tests with both natural, distilled water and brine as the media. The results showed
that the liquid limit and fine particles increased when the soil was mixed with fresh/distilled water compared with brine
water. The soil can be classified as highly compressible with a low undrained shear strength. In terms of collapsibility,
the soil could be classified as slightly collapsible upon inundation with distilled water and moderately collapsible when
soaked in Dead Sea brine. The results are important when determining the height and nature of the dykes.
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