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HomePlug第一届电力线通信技术会议于2005年9月27至28日在美国旧金山召开,文章首先介绍了HomePlug电力线联盟及其成员会议情况,然后从HomePlug电力线通信技术的发展、标准化、芯片设计、产品开发、市场需求和商业化运营等方面,对HomePlug第一届电力线通信技术会议进行了综述,最后结合我国情况对会议的几点体会做了简要介绍。 相似文献
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This paper deals with the leader-following consensus problem for a class of multi-agent systems with nonlinear dynamics and directed communication topology. The control input of the leader agent is assumed to be unknown to all follower agents. A distributed adaptive nonlinear control law is constructed using the relative state information between neighboring agents, which achieves leader-following consensus for any directed communication graph that contains a spanning tree with the root node being the leader agent. Compared with previous results, the nonlinear functions are not required to satisfy the globally Lipschitz or Lipschitz-like condition and the adaptive consensus protocol is in a distributed fashion. A numerical example is given to verify our proposed protocol. 相似文献
75.
In this work, the development of a recommender system that aims to facilitate the indirect materials selection task for the creation of spare parts is proposed. In the industrial sector there are spare parts manufacturing companies, where there is a high rotation of staff and this leads to loss of knowledge as new users do not know what indirect materials they should select in the warehouse to create certain parts. The proposed system aims to integrate an indirect materials recommender system to assist this warehouse task. The proposed system is based on the non-personalized approach and similar order circumstances, to perform the recommendation process. From the evaluation of the proposed system, we could conclude that the indirect materials selection process for producing auto parts was improved. 相似文献
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This paper proposes a multiple region quantizer composed of quantizers defined on different disjunctive regions of an input signal. In particular, for the two region and the three region cases, the paper provides a complete optimization of a multiple region companded quantizer for the Laplacian source of unit variance. The analysis of the multiple region quantizer is limited to a three region case due to the complexity of the optimization problem and due to the fact that much more complex multiple region quantizer models obtained for a higher number of regions could slightly improve the performances. Two-stage optimization is performed with respect to the number of reconstruction levels of each quantizer composing the considered multiple region companded quantizer and with respect to the region bounds. It is shown that optimal parameters depend only on the fractional part of the required average bit rate. In order to design the three region optimal quantizer, Lloyd–Max's algorithm and Newton–Kantorovich iterative method are used with the three region optimal companded quantizer as the initial solution. The gradient Newton–Kantorovich iterative method is used to provide better convergence speed than Lloyd–Max's algorithm, which is essential in cases where effective initialization solution of Lloyd–Max's algorithm is missing. It is shown that the three region optimal companded quantizer have signal to quantization noise ratio value close to the one of the three region optimal quantizer, where a simpler design procedure is the benefit of the three region optimal companded quantizer over the three region optimal one. 相似文献
77.
Polymer-supported NHC–metal catalysts were prepared from chloromethyl polystyrene resin via two-step reaction. Metals were loaded into 1.6 – 16 mol% of total imidazolium and the remaining imidazolium chloride salt provided ionic liquid moiety. The formation of metal complex with the polymer-supported NHC ligand was analyzed by ATR FT-IR, XRD, and XPS. The synthesized polymer-supported NHC–metal catalysts were applied to the dehydration of fructose into HMF. The environmentally benign and inexpensive polymer-supported NHC–FeIII catalyst showed good catalytic activity and yielded HMF at 73% (with a conversion of 97%). It could also be reused without significant loss of catalytic activity. 相似文献
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地震引起的地质松动、滑坡、崩塌、植被破坏等很难在短时间内恢复原状或者稳定下来,并且上游水库为保证坝体安全而被迫大量放水,强烈的河道冲刷及山体滑坡会造成地表水体泥沙悬浮物质等大量增加,导致地表水厂原水浊度剧烈变化,严重影响水厂安全运行。以"5.12"地震时绵阳市第三水厂原水浊度变化为例,说明地震对地表水厂原水浊度的影响程度及影响时间,并针对震后地表水厂原水浊度可能出现剧烈变化(数值从几十至两三万NTU)的情况,提出地震灾区地表水厂应针对高浊度原水在原有常规工艺的基础上增设预沉池(自然预沉池或混凝预沉池)工艺,实践证明运行效果良好,为保障地震灾区其他城镇供水安全提供参考和技术支持。 相似文献
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近年来智慧政府建设蓬勃发展,其政务协同、数据共享的发展理念对政务系统整合提出了明确需求。本文以系统云迁移实践为基础,对政务系统特点和属性与系统云迁移策略之间的内在联系进行探究,创造性的提出了一套基于系统属性参量选择适用云迁移策略的推导规则,并将这套规则应用于实际的政务系统云迁移方案制定中。 相似文献
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我国青藏高原矿产地储备战略思考 总被引:3,自引:0,他引:3
做好矿产地储备工作,有利于保持我国优势矿产资源的国际优势地位、增强话语权,保障短缺大宗矿产资源的安全供应,促进矿产资源的代际合理分配和永续利用。在分析青藏高原地质工作相关情况的基础上,从维护国家经济安全、推进生态文明建设、平衡资源代际分配、增强国际市场话语权、化解产能过剩等方面论述青藏高原矿产地储备的必要性。同时,着力从矿种、区位、勘查程度和工作思路等方面展开对青藏高原矿产地储备的思考。最后针对性提出设立矿产地储备专项资金、建立矿产地储备管理体制和制定矿产地储备专项规划等对策建议。 相似文献