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991.
Qingyi Quan 《ETRI Journal》2010,32(3):479-481
An optimal multiuser detection algorithm with a computational complexity of O(K log K) is proposed for the class of linear multiple‐access systems which have constant cross‐correlation values. Here the optimal multiuser detection is implemented by searching for a monotone sequence with maximum likelihood, under the ranking of sufficient statistics. The proposed algorithm is intuitive and concise. It is carried out in just two steps, and at each step only one kind of operation is performed. Also, the proposed algorithm can be extended to more complex systems having more than a single cross‐correlation value. 相似文献
992.
新一轮课程改革的一个亮点是综合实践活动课程的实施,由于综合实践活动课具有其特殊性,所以在实施过程中会遇到各种问题,特别是在特殊教育学校,诸多方面的问题制约着综合实践活动课的开展。本文通过对部分特殊教育学校的调研,了解到在实施过程中的问题并进行了分析,同时提出了一些应对策略。 相似文献
993.
A method for the screening of multiple attribute decision-making problems is presented. The model assists the decision-maker in eliminating inferior alternatives and insignificant attributes prior to a detailed evaluation. A preliminary evaluation of the alternatives provides the information necessary for the reduction of the decision problem. The procedure calculates maximum preference factors on which the decision-maker can base his screening decisions. These factors assess the role of alternatives in the final ranking by estimating their potential to become superior to other alternatives. Since screening tasks are carried out early in decision-making, the information available is generally uncertain. Uncertainty is represented in the model using fuzzy sets. This framework permits the handling of both imprecise and precise (crisp) estimates of impacts and provides a possibil-istic assessment of the risk associated with screening decisions. 相似文献
994.
Naoya Katayama 《时间序列分析杂志》2009,30(5):487-504
Abstract. The portmanteau statistic based on the first m residual autocorrelations is used for diagnostic checks on the adequacy of fitting a model with varying m. In this article, we propose an approximation of the joint probability of multiple portmanteau tests with different degrees of freedom (DF). This distribution is easy to compute when all DF are even integers; its empirical behaviour is clarified in terms of asymptotic theory. 相似文献
995.
Anne-Thérèse KörtgenManfred Nagl 《Computers & Chemical Engineering》2011,35(4):724-735
Consistency between different design documents is most important, as these documents are usually elaborated by different persons. Consistency means that structures within different documents “match” each other and also the values of corresponding attributes. Interactive and incremental tools for building up and maintaining consistency - so-called integrators - install fine-grained relations (semantic links) between objects of these documents. Such integrators have been investigated for some time in different application domains (Nagl, 1996).This paper deals with two extensions of integrators (
[K?rtgen, 2009a] and [K?rtgen, 2009b]). Both are devoted to speed up the (re-)integration process. The first extension makes use of the still valuable information of links damaged due to changes of documents. The second reuses consistent documents of past projects, to find out big and suitable related parts of design documents or of corresponding underlying knowledge. This paper is written for a chemical engineer and, therefore, emphasizes the tool functionality side. 相似文献
996.
通过傅里叶变换,采用谐波反应法计算并分析建筑自保温墙体的对温度波和热流波的响应,结合墙体的衰减倍数和延迟时间可以获得新型自保温墙体的热稳定性,从而为建筑自保温墙体的热稳定性优劣提供理论依据;根据自保温墙体自身的一些不足,提出了相应的改进措施,从而可以更好的优化并普及这类新型建材。 相似文献
997.
煤与瓦斯突出是一种复杂的动力现象,突出的类型不同、引起突出的危险因素不同,预测指标对其的敏感性也就不同,选择适应的突出危险性预测敏感指标及突出敏感指标的临界值,研究可靠的突出预测手段和方法来实现对突出危险性的准确预测,是指导突出防治工作的重要技术基础,而为了获得突出敏感指标的临界值就必须对煤的多元物性参数进行实验研究,掌握煤层的各项物化性质,是有效确定防治突出方法体系的关键基础。 相似文献
998.
This study advocates a multi-dimensional urban planning strategy to help combat climate change under local—and not national—policies. However, the literature does not provide adequate guidance to local governments seeking to enhance urbanization and in turn reduce vehicular carbon dioxide (CO2) emissions. Therefore, this study sheds light on the effects of the following four urban planning instruments on vehicular CO2 emissions: urbanization promoting areas, urbanization control areas, urban planning taxes and property taxes. Using Japanese city-level data from 1990 to 2010, we find that the two urbanization area planning instruments and the urban planning taxes help lower emissions by increasing population density in low-density cities and that property taxes help reduce emissions in high-density cities. However, the increased population density associated with these instruments can lead to other negative outcomes, including increased traffic accidents, increased crime and a decrease in the facility condition index. City governments should consider complementary policies to mitigate such negative outcomes when employing planning instruments aiming to increase population density. 相似文献
999.
将有限元法同人工透射边界的处理方法结合起来,首次以一种图象清楚、过程简单、适应性强的计算方法对目标散射问题进行讨论,对简单散射问题与解析解对比,并讨论误差情况. 相似文献
1000.
李绍箕 《武汉大学学报(工学版)》1994,(1)
对多孔球为团相的三相流化床流动特性进行初步研究.讨论气体空塔流速、液体喷淋密度、填料静止高度等因素时多孔球作团相的三相流化床流动特性的影响.根据实验数据,用微机回归得最小流化速度、床层压降、床层膨胀高度的计算公式.并和空心圆球为团相的三相流化床流动特性作了比较. 相似文献