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81.
蒋建文  江红军  牟奎 《水力发电》2007,33(2):73-74,80
本文首先介绍自动发电控制的基本原理和基本功能,然后介绍紫坪铺电厂AGC程序基本功能。作为水利枢纽工程,紫坪铺电厂的AGC有自身的特点,如电调服从水调,在保证下游供水的条件下实现自动发电控制,限制功率调节速度等,所以在实际运行中碰到许多特殊问题。为保证AGC功能的正常实现,采用一些特殊的方法解决以上问题。如通过设置最小下泄流量保证下游供水,限制功率调节步长解决功率变化过大等问题。通过试验。紫坪铺电厂在保证下游供水的前提下,顺利实现AGC各项功能,为作为水利枢纽工程的电站实现AGC提供了宝贵的经验。  相似文献   
82.
张杰  熊玮 《世界建筑》2004,(11):90-95
本文通过量化分析探索了清代皇家园林规划设计的控制规律及相关理论。  相似文献   
83.
This paper presents a novel neural network (NN) to control an ammonia refrigerant evaporator. Inspired by the latest findings on the biological neuron, a dynamic synaptic unit (DSU) is proposed to enhance the information processing capacity of artificial neurons. Treating the dynamic synaptic activity after the nonlinear somatic activity helps to capture the dynamics demarcated by the Gaussian activation pertaining to the input space. This practice leads to a remarkable reduction in curse of dimensionality. The proposed NN architecture has been compared with two other conventional architectures; one with dynamic neural units (DNUs) and the other with nonlinear static functions as perceptrons. The objective is to control evaporator heat flow rate and secondary fluid outlet temperature while keeping the degree of refrigerant superheat in the range 4–7 K at the evaporator outlet by manipulating refrigerant and evaporator secondary fluid flow rates. The drawbacks of conventional approaches to this problem are discussed, and how the novel method can overcome them are presented. An evolutionary approach is adopted to optimize the parameters of the NN controllers. Then evaporator process model is accomplished as a combination of governing equations and a sub NN resulting in a simple and sufficiently accurate model. The effectiveness of the proposed dynamic NN controller for the evaporator system model is validated using experimental data from the ammonia refrigeration plant.  相似文献   
84.
本文对当前城南地区汾河以东防洪存在的诸多隐患进行了阐述,并提出了相应的见解与措施。  相似文献   
85.
The objective, strategy, and implementation details of a new undergraduate course, Internet-based Instrumentation and Control, are presented. The course has a companion laboratory that is supported by the National Science Foundation and industry. The combination is offered to senior-level undergraduate engineering students interested in sensing, instrumentation, control, and web programming that want to learn more about the integration of these technologies for solving real-world engineering problems. The course will also be offered to gifted high school seniors with similar interests and can serve as a vehicle to attract them to engineering disciplines. Preliminary assessment of the first offering of the course is encouraging and has shown that the course has achieved success in helping students understand concepts and master basic technologies for developing Internet-based automatic systems.  相似文献   
86.
This paper presents a novel concept for power quality hardware and software architecture. Software tools related to detection, classification and characterization of power quality events can be integrated into a Distribution Control Center in which the interconnection between different subsystems is being carried out through the Internet allowing flexibility to the system. This system is implemented using wavelet analysis applied in all proposed algorithms. Different power quality events are taken as examples to illustrate the capabilities of the proposed method. The obtained results reveal that the proposed architecture is feasible to be implemented as an integral part of a control center system.The proposed system has the property of fast and accurate detection and classification of any power quality disturbance event and introduces a new PQ index determination that allows characterizing any type of disturbance including the non-periodic signals.  相似文献   
87.
通过对大型住宅区“深圳市新亚洲花园”工程规划及建筑方案创作构思的分析,实现住宅提升人们生活品质的设计思想,同时,在规划设计上对住宅开发在经济市场上如何提升竞争力做了有益探索。  相似文献   
88.
We present two proactive resource allocation algorithms, RBA*-FT and OBA-FT, for fault-tolerant asynchronous real-time distributed systems. The algorithms consider an application model where task timeliness is specified by Jensen's benefit functions and the anticipated application workload during future time intervals is described by adaptation functions. In addition, we assume that reliability functions of processors are available a priori. Given these models, our objective is to maximize aggregate task benefit and minimize aggregate missed deadline ratio in the presence of processor failures. Since determining the optimal solution is computationally intractable, the algorithms heuristically compute sub-optimal resource allocations, but in polynomial time. Experimental results reveal that RBA*-FT and OBA-FT outperform their non-fault-tolerant counterparts in the presence of processor failures. Furthermore, RBA*-FT performs better than OBA-FT, although OBA-FT incurs better worst-case and amortized computational costs. Finally, we observe that both algorithms robustly withstand errors in the estimation of anticipated failures.  相似文献   
89.
聚合反应器是无法检修设备,不允许打开,所以聚合反应器的制造质量必须严格控制,在设备制造过程中,严格按照设计图纸、技术要求及国家现行标准,进行控制设备制造、检验和验收,使制造质量达到规定要求。  相似文献   
90.
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