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排序方式: 共有2311条查询结果,搜索用时 15 毫秒
141.
中低品位磷矿高效清洁综合利用是中国基础磷化工产业发展中遇到的共性瓶颈问题。以中低品位磷矿磷-钙-镁一体化综合利用中试成果为基础,通过创新集成技术对中低品位磷矿直接进行处理,获得高品质磷精矿[w(P2O5)≥36%、w(MgO)≤0.5%]可用于任何湿法磷酸及热法黄磷生产工艺,同时回收高附加值的氢氧化镁和轻质碳酸钙。该工艺磷全部回收、无尾矿产生、实现了废水近零排放,项目的实施对推动中国磷化工产业可持续发展及从源头解决“三磷”问题具有重要意义。 相似文献
142.
YU Shitao YANG Shiwei YANG Lin GONG Yuanming ZHUO Bin Institute of Automotive Electronic Technology Shanghai Jiaotong University Shanghai China 《机械工程学报(英文版)》2007,20(1):25-30
A real-time operating system (RTOS), also named OS, is designed based on the hardware platform of MC68376, and is implemented in the electronic control system for unit pump in diesel engine. A parallel and time-based task division method is introduced and the multi-task software architecture is built in the software system for electronic unit pump (EUP) system. The V-model software development process is used to control algorithm of each task. The simulation results of the hardware-in-the-loop simulation system (HILSS) and the engine experimental results show that the OS is an efficient real-time kernel, and can meet the real-time demands of EUP system; The built multi-task software system is real-time, determinate and reliable. V-model development is a good development process of control algorithms for EUP system, the control precision of control system can be ensured, and the development cycle and cost are also decreased. 相似文献
143.
This paper presents an efficient dynamics-based computer animation system for simulating and controlling the motion of articulated figures. A non-trivial extension of Featherstone's O(n) recursive forward dynamics algorithm is derived which allows enforcing one or more constraints on the animated figures. We demonstrate how the constraint force evaluation algorithm we have developed makes it possible to simulate collisions between articulated figures, to compute the results of impulsive forces, to enforce joint limits, to model closed kinematic loops, and to robustly control motion at interactive rates. Particular care has been taken to make the algorithm not only fast, but also easy to implement and use. To better illustrate how the constraint force evaluation algorithm works, we provide pseudocode for its major components. Additionally, we analyze its computational complexity and finally we present examples demonstrating how our system has been used to generate interactive, physically correct complex motion with small user effort. 相似文献
144.
叙述了祥光清洁高效铜电解新技术的应用状况。就该技术实现的理论基础、工艺设计参数、车间配置、工艺技术攻关及指标比较等情况进行了详细的阐述,与常规铜电解技术的技术经济指标相比,该技术在清洁高效方面体现出了明显的优势。 相似文献
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147.
KYLIN-2是中国核动力研究设计院自主研发的先进中子学栅格(组件)计算软件,针对KYLIN-2软件中海量数据存储和处理的问题,提出一种基于对分层数据存储格式v5(HDF5)的计算数据存储方案。首先,对HDF5文件格式进行了研究;其次,根据KYLIN-2软件需求,设计了基于HDF5文件格式的组件库KYMRES;最后,通过自开发的HDF5文件读写工具完成了KYMRES库的实现过程。通过性能测试表明,基于HDF5文件格式的组件库KYMRES较常规存储方案具有更高的I/O效率,其读、写效率平均提升到旧算法的2.3倍和4.5倍。KYMRES库在海量数据存储和处理方面具有显著优越性,为KYLIN-2软件提供了一种新型的数据存储和管理方案。 相似文献
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149.
煤层气“井工厂”钻井完井技术探讨 总被引:1,自引:0,他引:1
煤层气井单井产量普遍较低,开发过程中只有实施低成本战略才能取得较好的经济效益。随着延川南煤层气区块产能建设的启动,对钻井周期及钻井成本提出了更高的要求。煤层气"井工厂"钻井开发模式的提出,对于达到低成本高效开发煤层气的要求具有重要的意义。结合延川南煤层气区块的特点,在现有丛式井钻井技术的基础上,从钻井设备、钻井顺序、关键工艺技术等几方面进行探讨和研究,提出了一套适合于延川南煤层气开发的"井工厂"钻井完井工艺技术,为区块大规模开发奠定良好的技术基础。 相似文献
150.
Steven S.W. LeeAuthor Vitae Po-Kai TsengAuthor VitaeAlice ChenAuthor Vitae 《Future Generation Computer Systems》2012,28(2):437-445
In order to lessen the greenhouse effects and diminish environmental pollution, reducing energy usage is important in designing next generation networks. Shutting down the network devices that carry light load and redirecting their traffic flows to other routes is the most common way to reduce network energy consumption. Since traffic demands among node pairs vary in different time periods, an energy efficient network has to dynamically determine the optimal active links to adapt itself to network traffic changes. However, in current IP networks, shutting down and/or turning on links would trigger link state routing protocols to reconverge to a new topology. Since the convergence time would take tens of seconds, routing table inconsistencies among routers would result in network disconnection and even worse, generating traffic loops during the convergence interval. Removing routing images inconsistent among routers to prevent loops is a critical issue in energy efficient network and this issue is still not considered in the green network design yet. The contribution of the paper is presented in two parts. First, we propose a comprehensive approach to determine a network topology and a link metric for each time period. Traffic engineering is considered in our design such that flows going on the energy-aware network are within a predetermined percentage of the link capacity such that no congestion occurs in a statistical manner. Second, to avoid transient loops during time period changes, we propose a Distributed Loop-free Routing Update (DLRU) scheme to determine the correct sequence for updating the routing table. A scrupulous proof was also presented to ensure the loop-free property of the DLRU. In this paper, we formulate an integer linear programming to determine this multi-topology and link weight assignment problem. Due to its NP-hard property, we propose an efficient algorithm, termed Lagrangian Relaxation and Harmonic Series (LR&HS) heuristic. Numerical results demonstrate that the proposed LRHS approach outperforms the other approaches on several benchmark networks and random networks by providing up to 35%-50% additional energy saving in our experimental cases. 相似文献