全极化SAR影像城区建筑密度分析

针对全极化SAR影像的建筑区特性,提出了一种基于极化特征共生矩阵的城区建筑密度分析方法。首先将极化特征与共生矩阵结合,在考虑建筑区极化散射机理和建筑朝向作用的同时,兼顾了建筑区的空间排列信息,在此基础上为了增强建筑密度的局部区域特性,将共生矩阵特征进行K-means聚类,结合图像分块形成标号直方图统计矢量,进而对该直方图统计矢量进行矢量量化实现SAR影像城区的建筑密度分级。RadarSat-2全极化SAR影像城区建筑密度分析的实验表明,该方法既适用于建筑朝向复杂城区也适用于建筑排列整齐城区的密度信息提取。     

语言竞争社会仿真模型与计算实验

语言竞争传播演化现象是典型的不能假设、无法进行"真实性实验"的社会科学问题,而建立在社会仿真模型基础上的计算实验是可行的方案。利用基于Agent的社会圈子网络理论并引入语言的内部词汇结构给出一种新的动态微观语言竞争社会仿真模型,其能反映语言内部结构演化涌现宏观语言态势的机制。计算实验表明:无干预调控情况下,语言共存的参数空间范围很小,很难达到共存状态,但在合适的时间窗口实施动态的调控政策可以让语言共存的参数空间显著扩大,在社会开放度高的情况下政策调控效果更好,这一发现扩展了之前人们对复杂网络语言竞争模型的认识。     

Ergonomic Analysis of Mobile Cart–Assisted Stocking Activities Using Electromyography

Workers in grocery stores are exposed to numerous musculoskeletal risks that can be reduced using assistive devices while performing stocking tasks. A regional grocery store has recently deployed a mobile cart without comprehension of its ergonomic impact on workers, which this article investigates using normalized electromyography data (%MVC). This article studies not only ergonomic impact based on %MVC values but also work performance represented by a muscle force metric (MFM). The results from this study showed highest muscle groups in %MVC and MFM were the erector spinae and triceps. Interestingly, muscle activations on erector spinae were reduced when mobile cart is used. %MVC and MFM distribution for value‐added‐ and non‐value‐added subtasks were slightly different, with larger differences observed for non‐value‐added tasks. Video recordings revealed higher work performance when the mobile cart is used. In future research, the number of participants will be increased to further validate the results from this study.     

Novel neural network modeling method and applications

Neural networks play an important role for designing the parametric model of electromagnetic structures. The current neural network methods are unfit for a circuit model with many input variables because it is costly to extract a large number of the training data and test data to complete the highly nonlinear mapping approximation. This article proposes a new neural network modeling method—the multidimensional neural network model, which can be used to solve the issue of multivariable radiofrequency and microwave passive device modeling. The entire multidimensional neural network modeling problem is simplified into a set of neural network submodels through decomposition method. Then the submodels are combined into an equivalent model, and the final entire model is produced through the neural‐network mapping model developed with the submodels and equivalent model. A microstrip hairpin filter model is developed using the proposed method. The simulation results show the correctness and the effectivity of the proposed method. © 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:769–779, 2015.     

Parametric Stabilization of Quantized Interconnected Systems with Application to Coupled Inverted Pendulums

This paper studies the analysis of parametric stability and decentralized state feedback control of a kind of quantized interconnected systems. The output of each controller is quantized logarithmically before it is input to the subsystem, and the quantized density would affect the stability of the systems. First, a decentralized state feedback controller is designed for interconnected systems without quantization and the corresponding stable region is obtained. Second, for a given controller, the lower bound of the quantization density is evaluated from parameters of local controllers. Finally, the proposed method is applied to coupled inverted pendulums systems which can be viewed as quantized interconnected systems. The simulation results show that by using the proposed quantized controllers, the interconnected inverted pendulum systems are parametrically stabilized.     

Research on social relations cognitive model of mobile nodes in Internet of Things

Interaction and communication between humans with smart mobile devices are a new trend of development in Internet of Things (IoT). With the powerful sensing capability of smart device and human mobility, various services could be provided by building a trusted chain between service requesters and suppliers. The cognition of social relations between mobile nodes is the basis of final mobile-aware services. It involves many decision factors, such as time, space and activity patterns. Using social network theory, a new cognitive model for social relations of mobile nodes in IoT is proposed. Firstly, nodes' social relations are reasoned and quantified from multiple perspectives based on the summary of social characteristics of mobile nodes and the definition of different decision factors. Then the location factor, interconnection factor, service evaluation factor and feedback aggregation factor are defined to solve the shortcomings in existing quantitative models. Finally, the weight distribution is set up by information entropy and rough set theory for these decision factors; it can overcome the shortage of traditional methods, in which the weight is set up by subjective ways and hence their dynamic adaptability is poor. We compare our cognitive model to existing models using MIT dataset by defining a variety of test indicators, such as network overall density (NOD), the degree center potential (DCP), the network distribution index (EI), etc. Simulation results show that, the cognitive model has better internal structure and significant validity in network analysis, and thus can provide mobile-aware service effectively in dynamic environment.     

广州市疏浚淤泥固化技术与工艺探讨

就疏浚淤泥的固化处置方法进行了论述,并结合广州市疏浚淤泥固化处置项目,主要探讨了广州市疏浚淤泥固化技术原理、固化剂以及工艺和设备,并对淤泥固化技术工程应用和固化效果进行了研究.     

芙蓉江清溪水电站发电引水系统设计及施工优化

贵州芙蓉江清溪水电站发电引水工程由于受地形、地质条件及设计方案限制,其施工工期在工程总进度计划中为控制性关键线路.由于采纳了作者的优化建议,对设计方案和施工布置进行了适当优化,实际施工中不仅提前完成了该项工程,有效地避免了施工干扰,还节省了工程投资,取得了较好的社会效益及经济效益.     

长春市电子政府的现状及构建对策分析

本文在详细分析电子政府构建的意义和价值的基础上,对长春市的电子政府的发展现状进行了分析,并对长春市电子政府的构建时策进行了分析和探讨.     

码书距离排序对索引压缩算法的性能改进

图像经过矢量量化后得到的索引图具有很强的统计相关性,从而使得邻近块的索引以较大的概率相等或偏移量较小。按照某种准则对码书进行排序,可以有效增强索引之间的相关性。基于平方欧几里得距离提出一种新的码书按距离排序方法。与传统的按均值、方差和能量等排序方法相比,距离排序能大大提高索引图的相关性,使索引之间的偏移量向值小的方向明显集中。将距离排序后的码书用于AICS(adaptive index coding scheme)算法,实现了更好的压缩性能。