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161.
Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related mortality worldwide. New insights into the pathogenesis of this lethal disease are urgently needed. Chromosomal copy number alterations (CNAs) can lead to activation of oncogenes and inactivation of tumor suppressors in human cancers. Thus, identification of cancer-specific CNAs will not only provide new insight into understanding the molecular basis of tumor genesis but also facilitate the identification of HCC biomarkers using CNA. 相似文献
162.
Awareness of the user's current context, that is, the task the user resides in, can allow for various ways of supporting their work. In this article we present a novel approach for mining user's regular tasks on the basis of temporal proximity of users’ desktop actions without user intervention in a completely automatic, unobtrusive, and unsupervised manner. The proposed method is based on time-based clustering of a user's desktop actions and, in contrast to previous approaches, it does not enforce fixed time constraints on the mined actions, and typical transition times, when they exist, emerge from the logged activity data for that specific user. The performance of our technique was evaluated on a large data set of 724 days of desktop work by five knowledge workers. The results showed that our approach performed very well and was able to cluster those temporally proximate user actions that commonly used fix time window techniques fail to deal with. Notably, the main improvement is in the recall of the tasks, where our approach recalled 10.18% more actions than the predefined time window technique. 相似文献
163.
An embedded system is a system that computer is used as a component in a larger device.In this paper,we study hybridity in embedded systems and present an interval based temporal logic to express and reason about hybrid properties of such kind of systems. 相似文献
164.
When two targets (T1, T2) are presented amongst a rapid stream of distractors, T2 accuracy is impaired if the targets are separated by at least one distractor (attentional blink). However, this impairment largely disappears if the targets follow one another directly (lag-1 sparing), and, in fact, as many as four or five consecutive targets may be identified quite accurately under these conditions (extended sparing). Although all current models propose a common mechanism for both lag-1 and extended sparing, this hypothesis has yet to be tested. To this end, we examined the effect of various types of attentional switches, known to impact lag-1 sparing, on extended sparing in order to determine whether they would have a similar effect. Results suggested substantial parallels between the two types of sparing. We discuss these results in terms of a unified account of sparing in temporal object perception. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
165.
Connie M. Borror 《Quality and Reliability Engineering International》2011,27(4):479-487
In this paper, we review two common measurement system indices and a common process capability index. With some simple plots, it will be shown that the traditional guidelines for these measurement system indices can often misdirect improvement efforts. By taking advantage of the relationship between the measurement system indices and the process capability index, two‐dimensional guidelines that can be used as an alternative to the traditional guidelines are developed. These two‐dimensional guidelines are intended to help address adequacy of the measurement system and better direct improvement efforts to where there will be the most benefit. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
166.
《Ergonomics》2012,55(11):1655-1663
Abstract Two groups of subjects designated ‘good’ (n= 12) and ‘poor’ (n= 10) catchers on the basis of a task-specific criterion were required to catch, one-handed, balls projected from a ball-projection machine under eight different conditions. Four of these comprised the ‘environment illuminated’ conditions (full light; hand obscured by an opaque screen; a see-through screen and an external vertical reference frame in the field of view) and four others the ‘environment dark’ conditions (catching hand wearing a glove painted with luminescent paint and u. v. illuminated ball in an otherwise dark room; ball illuminated by u. v. light; luminescent hand and external luminescent vertical reference plus u. v. illuminated ball; u. v.-illuminated ball, plus luminescent vertical reference). While clear and significant differences - as was to be expected from the selection criteria imposed - were shown between the groups of ‘good’ and ‘poor’ catchers for all three dependent variables-number of catches, spatial errors and temporal errors-it was demonstrated that, for both groups, degrading the environment, by reducing the information available, resulted in a significant performance decrement on the dependent variables ‘number of catches’ and ‘temporal errors’. ‘Poor’ catchers were also shown to make significantly more spatial errors than ‘good’ catchers. Whereas the latter finding confirms earlier findings reported in the literature, the significant effect on performance of degrading the environment -particularly with respect to temporal errors - is new. The finding is discussed in the framework of the use of ‘tau’ (time to contact) in making judgements about when to initiate the grasp response. 相似文献
167.
《Ergonomics》2012,55(1):79-90
Abstract There is a need for standardized methods for testing vehicle seats. Such methods would allow for the direct comparison of the merits of seats of diverse types and designs. At the present time standardized testing procedures are not possible because the dynamic characteristics of the human subjects occupying the seat during testing vary widely from man to man and affect the seat response. Testing with dead weight loading does not accurately portray the dynamic characteristics of the seat. A damped spring-mass system closely approximating to the dynamic characteristics of a seated man to vertical modes of vibration has been developed as the basis on which a standardized vehicle seat testing procedure can be built. Analysis of the problem by means of mechanical impedance techniques indicated that a two-degree-of-freedom system was sufficient to simulate the major dynamic characteristics of man in the frequencies below 10 Hz where seat vibration is most severe. Test procedures have been developed which utilize the man-simulator as the seat load. Results of these tests will be useful because they do not contain the subject variable and therefore can be compared directly with results obtained in other laboratories using the same methods. 相似文献
168.
169.
SAR图像固有的斑点噪声严重影响了图像的判读和后续处理,因此抑制SAR图像斑点噪声显得尤其重要。一个良好的斑点噪声抑制算法应该在降低斑点噪声的同时,能很好地保持图像的细节特征,但现有的去噪算法没有一种能够完美地解决这个问题的。本文基于SAR图像斑点噪声滤波的重要性以及存在的问题,将整体变分偏微分方程用于去除斑点噪声。根据整体偏微分方程建立了去噪模型,并分析了模型的性能和参数选择的重要性。通过实验验证了该算法的有效性,并以峰值信噪比(PSNR)为评价准则,利用多项式拟合方法选择了最优参数。引入边缘保持指数(EPI),与其他滤波算法比较,本算法在去除噪声的同时较好地保持了边缘。 相似文献
170.
Chang Liu Takao Tsuji Tsutomu Oyama 《IEEJ Transactions on Electrical and Electronic Engineering》2012,7(5):471-477
In the future, a large number of distributed generators are expected to be connected to the distribution system. However, with the connected capacity of distributed generation (DG) increasing, the problems of short‐circuit capacity (SCC) over the interrupting capacity of the circuit breaker (CB) and power loss increases due to reverse power flow from DG are inevitable. In this paper, a reconfiguration methodology based on an optimal algorithm is applied to the distribution system with DG to minimize power loss, taking into account the SCC. Moreover, in order to further reduce the loss, the daily load variation is also considered and the optimal model decided by calculations. Finally, to illustrate its application, the methodology is applied to a case study of a 33‐bus system with decentralized DG units. The results show that this method is obviously able to reduce power loss and make the network operate in the optimal mode with normal load variation, at the same time decreasing the SCC within the interrupting maximum of the faulty CB. Moreover, the whole voltage profile is also improved. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献