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101.
Nir Becker 《国际水资源开发杂志》1996,12(1):17-32
The growing demand for water by countries in the eastern Mediterranean raises the need to explore ways and means to ameliorate water scarcity. Economists have for some time proposed methods of more efficient exploitation of existing water supplies. Specifically, by employing m arket incentive mechanisms to encou rage voluntary water sharing among countries and regions is likely to lead to greater efficiency in water utilization. This paper explores the efficiency gains associated with re-allocating fresh water resources in the eastern Mediterranean through water rights markets. The results suggest that all parties involved might benefit to a greater or lesser degree from trading in water rights. 相似文献
102.
A novel integrated-optic coupling configuration if proposed. The device operation is based on the confinement of the coupling zone to the length of a very short Fabry-Perot cavity. The cavity is electrooptically coupled with a parallel outcoupling guide. By employing accurate lithographic techniques for the fabrication of milled integrated mirrors, with total lengths of the order of 5-10 μm, devices 100 to 200 μm long can be considered. These can perform full coupling operation at bandwidths in the range of many tens of gigahertz with typically a 12-15-dB extinction ratio. The same configuration can also be used for low-frequency switching, where an extinction ratio of >20 dB is expected. Calculated results are based on the parameters of Ti:LiNbO3 waveguides supporting 1.53-μm wavelength TM mode 相似文献
103.
Most concurrent data structures being designed today are versions of known sequential data structures. However, in various cases it makes sense to relax the semantics of traditional concurrent data structures in order to get simpler and possibly more efficient and scalable implementations. For example, when solving the classical producer-consumer problem by implementing a concurrent queue, it might be enough to allow the dequeue operation (by a consumer) to return and remove one of the two oldest values in the queue, and not necessarily the oldest one. We define infinitely many possible relaxations of several traditional data structures and objects: queues, stacks, multisets and registers, and examine their relative computational power. 相似文献
104.
The effect of intraparticle forced convection on the effectiveness of a porous catalyst was studied experimentally. Depolymerization of paraldehyde, catalysed by nickel-sulfate supported on cylindrical pellet of porous silica-gel, was measured in a basket-type reactor. The effective reaction rate increased with increasing the intensity of convective fluxes within the porous pellets. The dependence of this enhancement on the Peclét number and Thiele modulus of the system shows good qualitative agreement with predictions based on idealized models. 相似文献
105.
Decision trees have three main disadvantages: reduced performance when the training set is small; rigid decision criteria; and the fact that a single "uncharacteristic" attribute might "derail" the classification process. In this paper we present ConfDTree (Confidence-Based Decision Tree) -- a post-processing method that enables decision trees to better classify outlier instances. This method, which can be applied to any decision tree algorithm, uses easy-to-implement statistical methods (confidence intervals and two-proportion tests) in order to identify hard-to-classify instances and to propose alternative routes. The experimental study indicates that the proposed post-processing method consistently and significantly improves the predictive performance of decision trees, particularly for small, imbalanced or multi-class datasets in which an average improvement of 5%-9% in the AUC performance is reported. 相似文献
106.
Mingxing He Shi-Jinn Horng Pingzhi Fan Muhammad Khurram Khan Ray-Shine Run Jui-Lin Lai Rong-Jian Chen Adi Sutanto 《Expert systems with applications》2011,38(10):12018-12027
Phishing attack is growing significantly each year and is considered as one of the most dangerous threats in the Internet which may cause people to lose confidence in e-commerce. In this paper, we present a heuristic method to determine whether a webpage is a legitimate or a phishing page. This scheme could detect new phishing pages which black list based anti-phishing tools could not. We first convert a web page into 12 features which are well selected based on the existing normal and fishing pages. A training set of web pages including normal and fishing pages are then input for a support vector machine to do training. A testing set is finally fed into the trained model to do the testing. Compared to the existing methods, the experimental results show that the proposed phishing detector can achieve the high accuracy rate with relatively low false positive and low false negative rates. 相似文献
107.
Paul M. Young Handoko Adi Tajel Patel Katherine Law Philippe Rogueda Daniela Traini 《Journal of aerosol science》2009,40(4):324-337
A fundamental study of the interactions between binary particulate formulations in HFA-based pressurised metered dose inhaler (pMDI) systems was undertaken. Differences in the surface energetics of lactose, mannitol and sibenadet hydrochloride were observed, which could be related to the degree of particle adhesion/cohesion, the sedimentation rate and the aerosolisation performance of formulations containing different mixtures of these components. In general, lactose was shown to be the most cohesive material and readily formed coarse aggregates with sibenadet hydrochloride which sedimented rapidly. This had the greatest effect on aerosolisation performance at high-lactose concentrations (and low-sibenadet hydrochloride concentrations), where heavily agglomerated particles were observed in collected samples of the emitted aerosol. A model, relating the adhesive and cohesive forces between the components in these systems has been proposed, which satisfactorily describes these phenomena. Furthermore, although the more energetic systems were shown to result in significantly decreased aerosol performance, the through-life performance was enhanced. 相似文献
108.
Nir Tessler Yevgeni Preezant Noam Rappaport Yohai Roichman 《Advanced materials (Deerfield Beach, Fla.)》2009,21(27):2741-2761
Semiconducting polymers and small molecules form an extremely flexible class of amorphous materials that can be used in a wide range of applications, some of which are display, radio‐frequency tags, and solar cells. The rapid progress towards functional devices is occurring despite the lack of sufficient understanding of the physical processes and very little experience in device engineering. This tutorial review aims to provide sufficient intuitive background to draw more researchers to look into the fundamental aspects of device physics and engineering. 相似文献
109.
Synthesis of short-channeled amino-functionalized SBA-15 and its beneficial applications in base-catalyzed reactions 总被引:1,自引:0,他引:1
Amino-functionalized-SBA-15 catalysts with nanostructured hexagonal platelet morphologies were synthesized directly by using microwave synthesis from the hydrolysis and co-condensation of aminopropyltriethoxysilane (APTES) and sodium metasilicate under a strong acidic condition with the Pluronic P123 triblock copolymer as a structure-directing agent. The amino-functionalized-SBA-15 catalysts were proven by SEM and TEM techniques to have very short channels in the range of 200–300 nm perpendicular to the hexagonal platelet morphologies. These short-channeled catalysts were proven to be effective heterogeneous catalysts in liquid-phase reactions such as Knoevenagel and Claisen-Schmidt condensations as well as in Henry reaction. They exhibited greatly improved catalytic activities over the typical fibrous type SBA-15 catalyst having long channels. Obviously, the easy diffusion and rapid mass transfer of substrate into the short channel mesopores played important roles in the significant improvement in the catalytic activities. 相似文献
110.
Muhammed Iraqi Priyanka Bolel Rhitajit Sarkar Baisali Bhattacharya Muhammad Abu Ahmad Avishay Edri Laila C. Roisman Moshe Elkabets Walid Shalata Nir Peled Angel Porgador 《International journal of molecular sciences》2022,23(22)
Lung cancer cells in the tumor microenvironment facilitate immune evasion that leads to failure of conventional chemotherapies, despite provisionally decided on the genetic diagnosis of patients in a clinical setup. The current study follows three lung cancer patients who underwent “personalized” chemotherapeutic intervention. Patient-derived xenografts (PDXs) were subjected to tumor microarray and treatment screening with chemotherapies, either individually or in combination with the peptide R11-NLS-pep8; this peptide targets both membrane-associated and nuclear PCNA. Ex vivo, employing PDX-derived explants, it was found that combination with R11-NLS-pep8 stimulated antineoplastic effect of chemotherapies that were, although predicted based on the patient’s genetic mutation, inactive on their own. Furthermore, treatment in vivo of PDX-bearing mice showed an exactly similar trend in the result, corroborating the finding to be translated into clinical setup. 相似文献