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971.
972.
农产品市场的准确预测对指导农业生产、农产品流通和农产品消费有重要作用。本文提出了一种改进的结构化神经网络(ISNN),并基于ISNN构建了农产品产量预测模型;设计了一种优化性能更好的混合遗传算法(MGA),并采用MGA对ISNN预测模型进行训练。应用训练好的预测模型对某县最近10年的玉米总产品进行了预测分析。实验结果表明,该方法收敛速度快、学习能力强、预测精度较高、误差率较小。 相似文献
973.
分析了碱回收蒸发工段的工艺流程和控制要求,从硬件配置和软件设计等方面对碱回收蒸发工段进行了详细的叙述,同时采取软测量的方法测量黑液浓度,提出黑液浓度-压力串级控制方法;根据工艺要求设计出一种新型的DCS控制方法,它是由西门子公司的SIMATIC 400系列PLC连接ET200系列的分布式I/O系统及标准伺服控制系统组成的DP控制网络,通过相应的智能仪表及阀门对现场信号进行采集和控制;由此对碱回收蒸发工段实施集散控制的优化控制法案;工程实践表明,该系统在江苏甲乙粘胶公司生产线上投用,各种控制性指标能够很好地满足公司的要求。 相似文献
974.
水声信道是一个十分复杂的时空频变信道,其主要特征是复杂性、多变性、强多途和有限带宽;为了实现对水下设备的测距和遥控操作,针对水声信道的特性,系统采用时延编码方案,设置键盘和液晶显示屏能实现对系统的便利操作,并通过串口将测距结果传至电脑实现后处理;文中介绍了测距及系统通信原理,主机部分的总体设计、键盘以及液晶显示部分、数据采集和处理部分;经过多次水池和湖上实验,证明了此系统的可行性并实现了所有预期功能。 相似文献
975.
针对DSP芯片TS201的LINK口互连在高速数据通信中存在数据错误、突发数据块传输不稳定等缺点,在分析其通信协议的基础上,并结合实际应用,提出了设计LINK口通信的关键要求,给出设计的要点,设计与实现了TS201的LINK口互连以及FPGA(Xilinx公司的XC4VFX60)与TS201 LINK口互连,得到了实际测试结果;结果表明,所设计的LINK口互连具备的优点有:1)DSP之间通信可以达到单向600MB/s,双向1.2GB/s;2)DSP与FPGA之间通信可以达到单向450MB/s,双向900MB/s;3)LINK口的通信具备稳定、突发数据块传输无错误等性能。 相似文献
976.
977.
ICCD: Interactive Continuous Collision Detection between Deformable Models Using Connectivity-Based Culling 总被引:1,自引:0,他引:1
Tang Min Curtis Sean Yoon Sung-Eui Manocha Dinesh 《IEEE transactions on visualization and computer graphics》2009,15(4):544-557
We present an interactive algorithm for continuous collision detection between deformable models. We introduce multiple techniques to improve the culling efficiency and the overall performance of continuous collision detection. First, we present a novel formulation for continuous normal cones and use these normal cones to efficiently cull large regions of the mesh as part of self-collision tests. Second, we introduce the concept of “procedural representative triangles” to remove all redundant elementary tests between nonadjacent triangles. Finally, we exploit the mesh connectivity and introduce the concept of “orphan sets” to eliminate redundant elementary tests between adjacent triangle primitives. In practice, we can reduce the number of elementary tests by two orders of magnitude. These culling techniques have been combined with bounding volume hierarchies and can result in one order of magnitude performance improvement as compared to prior collision detection algorithms for deformable models. We highlight the performance of our algorithm on several benchmarks, including cloth simulations, N-body simulations, and breaking objects. 相似文献
978.
Memetic Algorithm With Extended Neighborhood Search for Capacitated Arc Routing Problems 总被引:2,自引:0,他引:2
Ke Tang Yi Mei Xin Yao 《Evolutionary Computation, IEEE Transactions on》2009,13(5):1151-1166
The capacitated arc routing problem (CARP) has attracted much attention during the last few years due to its wide applications in real life. Since CARP is NP-hard and exact methods are only applicable to small instances, heuristic and metaheuristic methods are widely adopted when solving CARP. In this paper, we propose a memetic algorithm, namely memetic algorithm with extended neighborhood search (MAENS), for CARP. MAENS is distinct from existing approaches in the utilization of a novel local search operator, namely Merge-Split (MS). The MS operator is capable of searching using large step sizes, and thus has the potential to search the solution space more efficiently and is less likely to be trapped in local optima. Experimental results show that MAENS is superior to a number of state-of-the-art algorithms, and the advanced performance of MAENS is mainly due to the MS operator. The application of the MS operator is not limited to MAENS. It can be easily generalized to other approaches. 相似文献
979.
Paper recommender systems in the e-learning domain must consider pedagogical factors, such as a paper's overall popularity and learner background knowledge — factors that are less important in commercial book or movie recommender systems. This article reports evaluations of a 6D paper recommender. Experimental results from a human subject study of learner preferences suggest that pedagogical factors help to overcome a serious cold-start problem (not having enough papers or learners to start the recommender system) and help the system more appropriately support users as they learn. 相似文献
980.
Xiaohua Tian Yu Cheng Bin Liu 《Multimedia, IEEE Transactions on》2009,11(6):1160-1169
This paper develops an efficient and scalable multicast scheme for high-quality multimedia distribution. The traditional IP multicast, a pure network-layer solution, is bandwidth efficient in data delivery but not scalable in managing the multicast tree. The more recent overlay multicast establishes the data-dissemination structure at the application layer; however, it induces redundant traffic at the network layer. We propose an application-oriented multicast (AOM) protocol, which exploits the application-network cross-layer design. With AOM, each packet carries explicit destinations information, instead of an implicit group address, to facilitate the multicast data delivery; each router leverages the unicast IP routing table to determine necessary multicast copies and next-hop interfaces. In our design, all the multicast membership and addressing information traversing the network is encoded with bloom filters for low storage and bandwidth overhead. We theoretically prove that the AOM service model is loop-free and incurs no redundant traffic. The false positive performance of the bloom filter implementation is also analyzed. Moreover, we show that the AOM protocol is a generic design, applicable for both intra-domain and inter-domain scenarios with either symmetric or asymmetric routing. 相似文献