数字机顶盒中USB大容量存储类主机的设计实现

介绍了USB大容量存储类主机在一种新型数字机顶盒中的设计与实现。该数字机顶盒方案成功的将USB大容量存储主机和网络终端和谐融合,使系统集电视、网络、USB主机功能于一体。

基于走跑类运动容量的城市公园园路形态特征研究——以哈尔滨为例

以实证分析方法,探讨影响走跑类运动容量的城市公园园路形态特征。首先,依据实测运动容量,将园路细化为无走跑类运动园路、低容量园路和高容量园路;其次,建立运动主体的环境感知偏好与空间形态特征关联;再次,结合数理模型,识别影响走跑类运动容量的显著空间形态特征,确定其适宜值范围,阐释其作用机理;最后,提出提升园路走跑类运动容量的规划布局与空间设计优化策略,以缓解市民日益增长的运动健身需求与有限的城市运动空间的现实矛盾。

基于K-means聚类的调查问卷动态赋权统计方法

为了保证调查问卷统计结果的可靠性,文章提出了一种基于K—means聚类算法的动态赋权统计方法。该方法在保证调查问卷效度和信度的基础上,分层次编制调查问卷问题量表;通过K—means聚类算法演绎不同层次下样本数据的归类分布情况,结合类容量大小确定样本的动态权重系数,进一步地赋权计算综合结果。将该方法应用于某高校图书馆服务质量满意度的调查实践,结果表明:动态赋权统计方法能够客观、真实地表征主体人对客体物的认知差异水平,其调查统计结果在有效性、可靠性等方面优于平均赋权算法,具有一定的实用价值。

USB接口的CDC&MSC复合设备设计与应用

在实际嵌入式项目开发过程中,需要通过一个USB接口实现虚拟串口通信和外部Flash芯片做虚拟U盘的复合功能,设计了一种基于USB的CDC类和MSC类复合设备,该设计以STM32F407系列单片机为核心,进行USB接口电路和外部Flash芯片的SPI接口电路设计,对USB设备库驱动程序中的底层驱动代码、各类描述符和初始化函数进行修改,最终完成USB复合设备的设计。USB复合设备功能测试结果表明,本设计不仅可以实现USB虚拟串口通信,还可以实现虚拟U盘功能,方便嵌入式系统的设计与开发。

考虑地理信息和行政边界的变电站供区优化

针对地理信息和行政边界等因素对变电站供区优化划分影响较大的情况,建立了供区优化数学模型,提出了考虑地理信息和行政边界的供区优化方法。该方法分别定义了目标函数和评价函数来检验规划结果的经济性和合理性,将地理信息和行政边界限制由罚函数方法来处理,结合改进K-Means算法有效求解该模型。通过理论分析分别推导了负荷节点的权重和聚类的容量大小。该算法考虑了负荷的权重和聚类的容量限制,因此重新定义了距离公式,并提出跳出局部解和提高计算速度的措施。算例表明规划结果具有科学性和可行性,为配电网的进步优化规划打下了基础。

USB主控制器在任意波发生器中的应用

研究和设计了嵌入式USB的主机系统,阐述了其工作机制,并给出了在任意波发生器控制面板上的具体实现,实现了改进波形数据输入方法的目的。首先研究了USB大容量存储类协议和USB主机在数据传输中的动作,然后根据任意波发生器的特点,利用SL811HS实现了USB主机功能,并在此基础上给出了USB存储设备的Bulk-In程序流程。

基于CH375的机车故障数据转储技术

在列车数据监控系统中,所采集数据的转储与分析是非常重要的环节之一,对便携性要求很高,而现在广泛应用的USB从机方案不够理想。为提高便携性,需要采用USB主机技术。机车故障检测记录仪以DSP5509为核心,实时监测来自机车的模拟和数字信号,对故障数据进行存储。针对DSP5509运行速度较快的特点,提出一种比CH375芯片厂商提供的文件级API函数更为优化的库函数结构。现场应用表明,该方案运行可靠,实现对128M片上存储数据进行一次性转储。

嵌入式系统中USB-HOST协议栈的设计

提出一种嵌入式系统中USB-HOST协议栈的设计思路,这个协议栈能够很方便地被移植到各种嵌入式平台,基于这个协议栈使得系统能够很方便地支持各种USB设备。该软件是USB-HOST协议栈最小实现系统,并为日后功能的更新预留接口。并基于这个协议栈实现了大容量设备的驱动,在TMS320DM642+SL811HS的硬件平台上调试通过,结合FAT32文件系统,可成功地在该平台上对USB移动硬盘进行文件的读写。

Linux+ARM下的USB驱动开发

本文介绍了嵌入式Linux下设备驱动程序的编写原理,并阐述了在Linux下Z228 USB的驱动程序的具体实现。在开发成功的案例下,讨论了USB驱动的编写技术。

Environmental Capacity of Petroleum Hydrocarbon Pollutants in Jiaozhou Bay, China: Modeling and Calculation

An environmental capacity model for the petroleum hydrocarbon pollutions （PHs） in Jiaozhou Bay is constructed based on field surveys, mesocosm, and parallel laboratory experiments. Simulated results of PHs seasonal successions in 2003 match the field surveys of Jiaozhou Bay resaonably well with a highest value in July. The Monte Carlo analysis confirms that the variation of PHs concentration significantly correlates with the river input. The water body in the bay is reasonably subjected to self-purification processes, such as volatilization to the atmosphere, biodegradation by microorganism, and transport to the Yellow Sea by water exchange. The environmental capacity of PHs in Jiaozhou Bay is 1500 tons per year IF the seawater quality criterion （Grade Ⅰ/Ⅱ, 0.05 mgLl） in the region is to be satisfied. The contribution to self-purification by volatilization, biodegradation, and transport to the Yellow Sea accounts for 48%, 28%, and 23%, respectively, which make these three processes the main ways of PHs purification in Jiaozhou Bay.

集合规划方法在航线网络枢纽选址上的应用

研究带有容量限制的单分配多枢纽网络选址问题,将问题简化为带有容量限制的聚类问题。通过节点之间的距离以及各个节点的需求量,根据聚类分析原理,采用集合规划的方法对问题进行建模,运用自然约束语言NCL,在POEM平台上对模型进行编程求解,并通过实例将计算结果在地图中可视化。运用模糊聚类方法对多枢纽选址位置进行分析。

Empirical Research on Carrying Capacity of Human Settlement System in Dalian City, Liaoning Province, China

Using the theories of population carrying capacity and ecological elasticity in other fields for reference, the connotation of regional human settlement system was defined from the viewpoint of the complex relationship among the factors such as regional population, resources, environment and economic and social development in the context of China′s rapid urbanization. Then the concept and characterization methods of the regional human settlement carrying capacity were proposed by means of population scale. Furthermore, a model of carrying capacity-pressure-state-response(CPSR) on regional human settlement system was established by referencing pressure-state-response(PSR) model, and the Catastrophe Theory was introduced to determine the corresponding standards of multi-criteria programming and evaluation. Taking Dalian City, Liaoning Province, China as an example, an empirical analysis on evaluation of human settlement system from 2000 to 2012 was carried out. The results showed that the carrying capacity of human settlement system in Dalian was fluctuating between 9.6 × 106 to 10 × 106 persons with a quantitative stage of the dynamic regulation. During the research period the load index of human settlement system in Dalian dropped from 0.96 to 0.84 with a lower pressure of human settlement system than the national average level. And the emergency response grades of human settlement system in Dalian were kept in grade Ⅱ(orange warning) or grade Ⅲ(yellow warning). Human settlement system of Dalian was in slight security state as a whole, but the load had a tendency of increase in recent years. The related departments should pay close attention to regional human settlement system and take active measures to improve human settlement by both intensity control and total quantity control. By comparison, analysis and discussion, it was considered that the results were basically accordded with the current situations of human settlement in Dalian, and the evaluation results were more reliable, visualized and easily applied in practice. Therefore, the above-mentioned concepts, characterization and evaluation methods of the regional human settlement system and carrying capacity could provide a new thought and method for quantitative evaluation of human settlement.

Research on Parallel K-Medoids algorithm based on MapReduce

In order to solve the bottleneck problem of the traditional K-Medoids clustering algorithm facing to deal with massive data information at the time of memory capacity and processing speed of CPU, the paper proposed a parallel algorithm MapReduce programming model based on the research of K-Medoids algorithm. This algorithm increase the computation granularity and reduces the communication cost ratio based on the MapReduce model. The experimental results show that the improved parallel algorithm compared with other algorithms, speedup and operation efficiency is greatly enhanced.

A TCAM-based Two-dimensional Prefix Packet Classification Algorithm

Packet classification (PC) has become the main method to support the quality of service and security of network application. And two-dimeusioual prefix packet classification (PPC) is the popular one. This paper analyzes the problem of ruler conflict, and then presents a TCAM-based two-dimensional PPC algorithm. This algorithm makes use of the parallelism of TCAM to lookup the longest prefix in one instruction cycle. Then it uses a memory image and associated data structures to eliminate the conflicts between rulers, and performs a fast two-dimeusional PPC. Compared with other algorithms, this algorithm has the least time complexity and less space complexity.

High Voltage Pulse Power and the Technics for the Capacitor Power-Storage Type

Lower hybrid wave （LHW）, electro cyclotron （EC） and neutral beam injection （NBI） etc. are the important methods of auxiliary heating. They would be devoted to the HL-2A tokamak step by step. In order to satisfy the debug of each system and the need of the experiment, the system should be equipped with high voltage pulse power （HVPP） according to the requirement.

Three Gorges Project:a project for ecological improvement and environmental protection in Yangtze River Basin

Seeking water and earning their livelihoods is the natural selection of human beings.Like other rivers on the earth,the Yangtze River is the birthplace of human civilization and survival.As an ecosystem,the Yangtze River Basin is evolving under the influences of natural factors and human activities.Because of soil erosion,pollution and human activities,the imbalance of secondary environment is exacerbated and the ecological environment has become more vulnerable,so it is urgent to mitigate and prevent the ecological crisis.The practice has proved that implementation of engineering measures is an effective way to improve the ecological environment.The Three Gorges Project (TGP) has a flood control storage capacity of 22.15 billion m 3,effectively storing the flood water upstream of Yichang,and protects 15 million people and 1.5 million hm 2 farmland.Furthermore,the project can prevent or slow down the sedimentation and shrinkage of the lakes in the middle Yangtze River such as Dongting Lake;with an average annual power generation of about 90 billion kW· h,it can significantly reduce the emissions of harmful gas like CO 2.In general,the construction of TGP is conducive to the ecological and environmental protection in the Yangtze River Basin and China,even the world.

一种嵌入式USB主机的应用

USB是一种得到了广泛应用的新型总线,被数据采集和仪器设备大量采用。文章描述了一种基于嵌入式USB主机的仪器数据存取系统,该系统利用嵌入式USB主机控制器来实现数据存储,使仪器可以脱离PC独立运行和将数据存储在移动USB存储设备中,扩大了该设备的使用范围。该设备经试用,可以正常存储数据文件。

Chemical Availability of Cd, Pb and Zn in Anthropogenically Polluted Soil: Assessing the Geochemical Reactivity and Oral Bioaccessibility

The most recent in vitro tests used to determine metal bioaccessiblility are generally time-consuming and expensive. This study aimed at determining potential relationships between the concentrations of metals extracted using single-extraction methods and the concentrations of bioaccessible metals assessed by a harmonised in vitro test, the Unified BARGE Method （UBM）. A total number of 27 soil samples were collected from kitchen gardens and lawns with various physicochemical parameters and contamination levels. Significant relationships were obtained between Cd, Pb and Zn extracted in gastric and gastrointestinal phases and using single extractions. The best relationhips were established using acetic and citric acids for Cd, whereas for Pb, citric acid and ethylenedi- aminetetraacetic acid （EDTA） were identified as the best extractants. These relationships were improved by means of a linear multiple regression with a downward stepwise procedure involving agronomic parameters （soil cation exchange capacity and assimilated P）. This method highlighted the fact that the cation exchange capacity and P contents in soils were the two main parameters that controlled the human bioaccessibility of Cd, Pb and Zn in the gastric phase. Besides, the metal concentrations extracted with the acetic and citric acids correlated well with the metal concentrations in the gastric and gastrointestinal phases, suggesting that the bioaceessible metals were mainly in a soluble form, weakly bound to the organic matter and associated with the carbonates and the Fe and Mn oxides/hydroxides in soils.

TEMPO-substituted polyacrylamide for an aqueous electrolyte-typed and organic-based rechargeable device

A hydrophilic radical polymer, poly（2,2,6,6-teteramethylpiperidinyloxyl-4-yl acrylamide） （PTAm）, was synthesized via oxidation of the corresponding precursor polymer, poly（2,2,6,6-teteramethylpiperidine-4-yl acrylamide）. Electrochemical properties of the PTAm layer were characterized in three aqueous electrolytes of sodium chloride （NaCl）, sodium tetrafluoroborate （NaBF4）, and sodium hexafluorophosphate （NaPF6） to optimize its activity as an organic cathode. The counter anion species significantly affected the capacity and the cycle performance of the PTAm layer. The PTAm layer in the presence of BF4？ displayed quantitative redox capacity beyond 1 μm layer thickness and maintained the discharging capacity of 110 mAh g-1 （97% vs. the calculated capacity） even after 1000 cycle charging/discharging, which could be ascribed to its appropriate affinity to the aqueous electrolyte without any dissolution into the electrolyte. A totally organic-based rechargeable cell was fabricated using PTAm and poly（N-4,4＇-bipyridinium-N-decamethylene dibromide） as the cathode and the anode, respectively, and the aqueous electrolyte of NaBF4. The cell gave a plateau voltage at 1.2 V both on charging and discharging and an excellent charging/discharging cyclability of ＆gt;2000 with high coulombic efficiency of ＆gt;95%.