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11.
Austin Turk theorizes that places in stratification hierarchies affect police–citizen encounters by reinforcing or reversing the positional authority of police officers. To this point, however, there have been only three direct tests of the stratification portions of Turk's theory. Two examined overt conflict and all represented Turk's concepts using aggregated measures. The results are mixed. The present research adds a fourth test to the stratification and policing literatures by examining the effects of aggregated as well as disaggregated measures of stratification reinforcers and reversals on traffic ticket decisions by Boston police officers during April and May of 2001. Net of important control measures, there is no support for Turk's theory using the aggregated stratification measures employed in previous research. However, support for Turk's theory is clearly visible when viewed through the lens of some of the disaggregated stratification measures advanced for the first time in present research. We conclude that more research is needed to determine whether stratification reinforcers and reversals are among the factors affecting people in police blue and the people they police, with a sustained focus on both aggregated and disaggregated measures.  相似文献   
12.
For a drifted multiple-input and multiple-output (MIMO) system, the double multivariate exponentially weighted moving average (dMEWMA) controller is a popular run-to-run (RTR) controller for adjusting the process mean to a desired target. The stability and performance of dMEWMA controller had been widely studied in literature. Although the dMEWMA controller (with suitable discount matrices) can guarantee long-term stability, it usually requires a moderately large number of runs to bring the process output to approach its desired target if the initial recipe is not chosen appropriately. Due to the initial recipe possibly having an infinite number of feasible solutions for MIMO systems, “how to determine an optimal setting for the initial recipe” turns out to be an interesting research topic. In this article, by solving a constrained optimization problem, we first obtain an optimal initial setting for the input recipe. Then, motivated by this setting, we propose an enhanced dMEWMA controller. The long-term stability conditions and short-term performance of the proposed controller are also addressed. Given a fixed and finite production run, it reveals that the proposed controller has the ability of reducing total mean squared error (TMSE) better than the conventional dMEWMA controller.  相似文献   
13.
介绍用两片GAL16V8芯片实现的十字路口交通管理器。一片GAL做成基于“最大长度移位寄存器型计数器”的可变模计数器,一片GAL做成控制器产生状态变量及红绿灯信号。电路简单,运行可靠。  相似文献   
14.
推进云南全面小康社会建设,必须加快交通建设步伐。云南交通建设的重点是公路建设,全面提高全省公路的质量和等级。要适应新的形势和要求,推进公路建设的市场化、集约化、生态化、社会化进程。  相似文献   
15.
本文给出一种新型模糊PID控制嚣的原理、设计和模拟分析.该控制器可广泛应用于各种复杂控制系统.  相似文献   
16.
太阳能驱动旅游船速度控制器的设计   总被引:1,自引:0,他引:1  
介绍了太阳能驱动旅游船动力系统的构成.在分析了电机于液体负载下的运动特点后,基于BUCK式DC/DC变换器,设计了适合在液体负载下工作的太阳能驱动旅游船的速度调整控制器,给出了实验和应用结果.  相似文献   
17.
Recently, Borgatti [Borgatti, S.P., 2005. Centrality and network flow. Social Networks 27, 55–71] proposed a taxonomy of centrality measures based on the way that traffic flows through the network—whether over path, geodesic, trail, or walk, and whether by means of transfer, serial duplication, or parallel duplication. Most of the extant centrality measures assume that traffic propagates via parallel duplication or, alternatively, that it travels over geodesics. Few of the other flow possibilities have centrality measures associated with them. This article proposes an entropy-based measure of centrality appropriate for traffic that propagates by transfer and flows along paths. The proposed measure can be applied to most network types, whether binary or weighted, directed or undirected, connected or disconnected. The measure is illustrated on the gang alliance network of Kennedy et al. [Kennedy, D.M., Braga, A. A., Piehl, A.M., 1998. The (un)known universe: mapping gangs and gang violence in Boston. Crime Prevention Studies 8, 219–262].  相似文献   
18.
针对传统Internet在流量工程方面的不足和越来越多新业务对流量工程的需求 ,文章分析了MPLS在流量工程方面的应用 ,详细介绍了实现MPLS流量工程的两种信令协议———CR -LDP和RSVP扩展 ,并通过对它们的基本特征、可扩展性和可行性方面的比较 ,得出CR -LDP优于RSVP扩展的结论。  相似文献   
19.
This paper presents a novel control algorithm to decrease the worst-case delay bound for high rate homogeneous and heterogeneous real-time flows when the network traffic load becomes heavy. The algorithm is adaptive based on the instantaneous network situations. It employs a generalized form of traditional (σ,ρ) regulator called the generalized (σ,ρ,λ) regulator that operates like the (σ,ρ) regulator under the normal network traffic load situation, but provides more regulations for the heavy network traffic load situation. For a set of real-time flows, we can show that D rg D g where D rg and D g are the worst-case delay bounds with the (σ,ρ,λ) regulator and the (σ,ρ) regulator respectively. More specifically, we have developed a set of formulas to set the parameters for the new regulator so as to reduce the worst-case delay bounds for the real-time flows. We can prove that there exists a threshold input rate ρ* such that D rg = D g for ρ≤ρ* and D rg < D g for ρ > ρ*. When the average input rate of real-time flows is very high, the generalized regulator can effectively control the delay. The extensive experiment data match our theoretical results. The part of this paper has been appeared in The 23 rd IEEE International Conference on Distributed Computing Systems, 2003. The work is supported by CityU strategic grant Nos: 7001777 and 7001709 and CityU ARP Project No. 9610027. H. Wang was partially supported by National Natural Science Foundation of China (10471088, 60572126) and CityU strategic grant no. 7001709. Wanqing Tu is now with Department of Computer Science, The Hong Kong University of Science and Technology. Clear Water Bay, New Territories, Kowloon, Hong Kong.  相似文献   
20.
介绍了可编程控制器(PLC)在洁净空调控制系统中应用的实例,对应用中遇到的问题提出了解决方案,并对PLC在洁净空调系统中推广使用的前景进行了分析。  相似文献   
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