A multi-sensor-based distributed real-time measurement system for glacier deformation

Glacier disasters occur frequently in alpine regions around the world,but the current conventional geological disaster measurement technology cannot be directly used for glacier disaster measurement.Hence,in this study,a distributed multi-sensor measurement system for glacier deformation was established by integrating piezoelectric sensing,coded sensing,attitude sensing technology and wireless communication technology.The traditional Modbus protocol was optimized to solve the problem of data identification confusion of different acquisition nodes.Through indoor wireless transmission,adaptive performance analysis,error measurement experiment and landslide simulation experiment,the performance of the measurement system was analyzed and evaluated.Using unmanned aerial vehicle technology,the reliability and effectiveness of the measurement system were verified on the site of Galongla glacier in southeastern Tibet,China.The results show that the mean absolute percentage errors were only 1.13%and 2.09%for the displacement and temperature,respectively.The distributed glacier deformation real-time measurement system provides a new means for the assessment of the development process of glacier disasters and disaster prevention and mitigation.

Scheduling transactions in mobile distributed real-time database systems

A DMVOCC-MVDA （distributed multiversion optimistic concurrency control with multiversion dynamic adjustment） protocol was presented to process mobile distributed real-time transaction in mobile broadcast environments. At the mobile hosts, all transactions perform local pre-validation. The local pre-validation process is carried out against the committed transactions at the server in the last broadcast cycle. Transactions that survive in local pre-validation must be submitted to the server for local final validation. The new protocol eliminates conflicts between mobile read-only and mobile update transactions, and resolves data conflicts flexibly by using multiversion dynamic adjustment of serialization order to avoid unnecessary restarts of transactions. Mobile read-only transactions can be committed with no-blocking, and respond time of mobile read-only transactions is greatly shortened. The tolerance of mobile transactions of disconnections from the broadcast channel is increased. In global validation mobile distributed transactions have to do check to ensure distributed serializability in all participants. The simulation results show that the new concurrency control protocol proposed offers better performance than other protocols in terms of miss rate, restart rate, commit rate. Under high work load （think time is ls） the miss rate of DMVOCC-MVDA is only 14.6%, is significantly lower than that of other protocols. The restart rate of DMVOCC-MVDA is only 32.3%, showing that DMVOCC-MVDA can effectively reduce the restart rate of mobile transactions. And the commit rate of DMVOCC-MVDA is up to 61.2%, which is obviously higher than that of other protocols.

Design and development of real-time query platform for big data based on hadoop

This paper designs and develops a framework on a distributed computing platform for massive multi-source spatial data using a column-oriented database(HBase).This platform consists of four layers including ETL(extraction transformation loading) tier,data processing tier,data storage tier and data display tier,achieving long-term store,real-time analysis and inquiry for massive data.Finally,a real dataset cluster is simulated,which are made up of 39 nodes including 2 master nodes and 37 data nodes,and performing function tests of data importing module and real-time query module,and performance tests of HDFS's I/O,the MapReduce cluster,batch-loading and real-time query of massive data.The test results indicate that this platform achieves high performance in terms of response time and linear scalability.

Research on Application Technology Oriented Rapid Response Manufacturing in the Distributed Network Environment

A new chance of developing traditional manufacturing industry comes forth with the development of network technology. Application technology oriented rapid response manufacturing in the distributed network environments, that is, how to take advantage of the Intranet and Internet, combine the numerous manufacturing resources spread around the region, the country and even the globe is the key to the agile design, manufacturing and the buildup of comprehensively competitive power, at the same time, is also an important research direction in the field of advanced manufacturing technology. Rapid response manufacturing in the distributed network environment is a newly manufactory pattern that can be used to implement the conception of agile design and manufacturing, but there are some new problems coming with it, which will directly influence the enterprise’s ability of rapid response in the distributed network manufacturing pattern and lead to the failure of the league and the lost of the given orders. In this paper, we establish some approaches to solve these problems in product development process. The paper then presents the research on key application technologies and solutions includes: network safety strategy which guarantees data transferring among the leaguer members, production data management based on Web/DOT (Distributed Object Technology) and XML criteria which guarantees data exchange in structure-variance characteristic environments, the network platform which provides the conversion service of different types of CAD files each other. All of these solutions are aim for technology problems existing in the distributed network environments and among the league members. Finally, the paper takes one project, that is, the establishment of the online application service system for Shanghai Advance Manufacturing Technology Research Center as a good instance.

Variation of spatio-temporal distribution of on-road vehicle emissions based on real-time RFID data

High-resolution vehicular emissions inventories are important for managing vehicular pollution and improving urban air quality. This study developed a vehicular emission inventory with high spatio-temporal resolution in the main urban area of Chongqing, based on realtime traffic data from 820 RFID detectors covering 454 roads, and the differences in spatiotemporal emission characteristics between inner and outer districts were analysed. The result showed that the daily vehicular emission intensities of CO, hydrocarbons, PM2.5, PM10,and NO_(x) were 30.24, 3.83, 0.18, 0.20, and 8.65 kg/km per day, respectively, in the study area during 2018. The pollutants emission intensities in inner district were higher than those in outer district. Light passenger cars(LPCs) were the main contributors of all-day CO emissions in the inner and outer districts, from which the contributors of NO_(x) emissions were different. Diesel and natural gas buses were major contributors of daytime NO_(x) emissions in inner districts, accounting for 40.40%, but buses and heavy duty trucks(HDTs) were major contributors in outer districts. At nighttime, due to the lifting of truck restrictions and suspension of buses, HDTs become the main NO_(x) contributor in both inner and outer districts,and its three NO_(x) emission peak hours were found, which are different to the peak hours of total NO_(x) emission by all vehicles. Unlike most other cities, bridges and connecting channels are always emission hotspots due to long-time traffic congestion. This knowledge will help fully understand vehicular emissions characteristics and is useful for policymakers to design precise prevention and control measures.

基于分布式事务的数据跨网交换技术

随着信息技术在社会各领域中的应用越来越深入,数据跨网交换与传输成为业务信息系统之间的重要途径。针对跨网数据交换存在的安全问题,分析了现有数据跨网交换方式在确保数据安全传输方面的不足,以及网络单向通信导致的无法利用常用事务模式的问题,提出了一种可屏蔽底层跨网硬件设备差异的基于分布式事务的数据跨网交换技术。对数据跨网交换方案设计过程进行了分解,并基于国产化平台进行了设计,实现了信息环境中数据跨网的安全交换。

Scalable and Adaptive Joins for Tra jectory Data in Distributed Stream System

As a fundamental operation in LBS(location-based services),the trajectory similarity of moving objects has been extensively studied in recent years.However,due to the increasing volume of moving object trajectories and the demand of interactive query performance,the trajectory similarity queries are now required to be processed on massive datasets in a real-time manner.Existing work has proposed distributed or parallel solutions to enable large-scale trajectory similarity processing.However,those techniques cannot be directly adapted to the real-time scenario as it is likely to generate poor balancing performance when workload variance occurs on the incoming trajectory stream.In this paper,we propose a new workload partitioning framework,ART(Adaptive Framework for Real-Time Trajectory Similarity),which introduces practical algorithms to support dynamic workload assignment for RTTS(real-time trajectory similarity).Our proposal includes a processing model tailored for the RTTS scenario,a load balancing framework to maximize throughput,and an adaptive data partition manner designed to cut off unnecessary network cost.Based on this,our model can handle the large-scale trajectory similarity in an on-line scenario,which achieves scalability,effectiveness,and efficiency by a single shot.Empirical studies on synthetic data and real-world stream applications validate the usefulness of our proposal and prove the huge advantage of our approach over state-of-the-art solutions in the literature.

Distributed Simulation Platforms and Data Passing Tools for Natural Hazards Engineering: Reviews, Limitations,and Recommendations

here has been a strong need for simulation environments that are capable of modeling deep interdependencies between complex systems encountered during natural hazards,such as the interactions and coupled effects between civil infrastructure systems response,human behavior,and social policies,for improved community resilience.Coupling such complex components with an integrated simulation requires continuous data exchange between different simulators simulating separate models during the entire simulation process.This can be implemented by means of distributed simulation platforms or data passing tools.In order to provide a systematic reference for simulation tool choice and facilitating the development of compatible distributed simulators for deep interdependent study in the context of natural hazards,this article focuses on generic tools suitable for integration of simulators from different fields but not the platforms that are mainly used in some specific fields.With this aim,the article provides a comprehensive review of the most commonly used generic distributed simulation platforms(Distributed Interactive Simulation(DIS),High Level Architecture(HLA),Test and Training Enabling Architecture(TENA),and Distributed Data Services(DDS))and data passing tools(Robot Operation System(ROS)and Lightweight Communication and Marshalling(LCM))and compares their advantages and disadvantages.Three specific limitations in existing platforms are identified from the perspective of natural hazard simulation.For mitigating the identified limitations,two platform design recommendations are provided,namely message exchange wrappers and hybrid communication,to help improve data passing capabilities in existing solutions and provide some guidance for the design of a new domain-specific distributed simulation framework.

A Review on TSO-DSO Data Exchange,CIM Extensions and Interoperability Aspects

The exchange of information between transmission system operators(TSOs)and distribution system operators(DSOs)is a common practice.However,the evolution of the regulatory frameworks in Europe has increased the need for enhancing TSO-DSO data exchange and interoperability.This paper provides an overview of the TSO-DSO data exchanges and demonstrates the best practices using International Electrotechnical Commission(IEC)common information model(CIM),including the implementation of IEC common grid model exchange standard(CGMES),and discussion of the corresponding advantages,disadvantages,and challenges.Furthermore,this paper evaluates and reports the activities already carried out within European projects,with particular focus on TSO-DSO interoperability.Finally,this paper concludes the need for TSOs and DSOs to rely on standard-based solutions when performing TSO-DSO data exchange,which enables the efficient operation and development of the future power systems.

基于VBA及AutoLisp混合编程数字化生成电力系统图的研究

建筑电气设计过程中需要编制负荷计算书、短路计算书等,使用VBA、AutoLisp进行混合编程,使AutoCAD文件内的竖向干线图输出关键信息至Excel电子表格进行电气计算,自动编制负荷计算书、短路计算书等,并在AutoCAD内生成电力系统图。

社保一体化服务平台设计

随着铁路企业改革持续深入,不断优化企业内设机构,企业内部人员流动更为频繁、职工社保关系更加复杂,管理难度不断加大。为了加快推进多层次铁路社保体系构建,从实际需求出发,采用SpringBoot框架,设计层级式多源数据交换算法,进行社保一体化服务平台建设。服务平台统筹加强社保、企业补充医保和企业年金各项业务之间的深度融合,实现各项业务高效经办和闭环管理,切实减轻基层单位负担,确保单位和职工及时掌握企业补充医疗保险及企业年金等待遇信息,显著提升企业社保管理能力和服务职工水平,为搭建多层次企业社保管理体系提供技术支持。

基于XML的数据交换系统设计

不同应用和运行环境的系统之间往往存在数据交换困难的问题,这个问题解决不好将造成系统间无法进行信息交换。为了达到信息交换的目的,一种做法是为每一特定的系统单独开发接口,这样做不仅效率低、工作量大,而且难以根据统一标准对系统进行集成。由于XML的特点,使其具有成为数据交换文件的能力。结合某物流配送系统的数据交换过程,提出了以XML文件作为数据交换平台的方法,并对系统的功能设计进行了介绍,满足了数据交换要求。

分布式信息系统中数据交换平台设计与实现

为了提高分布式信息系统的性能,加快系统间的数据流通实现信息的共享和集成,需要为分布式信息系统建立数据交换平台。通过对数据交换平台现有的一些解决方案分析,在研究JMS(Java message service)等技术基础上,设计并实现了新的数据交换平台。利用JMS消息模式实现消息持久化,以开源消息中间件为交换中心,在SOA(service-oriented architecture)平台技术上完成了分布式信息系统的数据交换平台。详细介绍了平台设计架构、信息交换过程、数据封装格式,重点描述了发送接口、轮循器以及发送接收功能等关键技术的实现工作,完成了大型分布信息系统中消息持久化、零配置以及快速、稳定消息传送的数据交换平台。

分布式数据交换平台在电子政务中设计与实现

为了解决当前电子政务系统中部门之间的资源共享和电子政务建设纵深发展的"瓶颈"问题,文中提出了一种在分布式网络环境下的数据交换平台.平台利用统一的消息服务来控制数据交换过程中复杂的控制信息交互,利用统一的管理机制和技术标准来解决数据交换过程中各种数据的传输;采用基于面向服务的架构设计模式、XML技术和消息中间件通讯原理,对多数据库交换产品及实现中需要解决的问题进行分析,搭建了一个分布式数据交换平台,充分体现了在跨平台应用中的优势,具有较强的实用性和通用性.实现了一个个高度自治、安全、便于管理的数据集成应用.

分布式数据挖掘中基于扰乱的隐私保护方法

通过设计一种随机数值片拆分统计机制,提出分布式环境下的匿名均值统计和匿名方差统计方法;结合同态加密机制,设计了分布式环境下的随机数据交换方法,实现了分布式环境中匿名数据交换机制.结合上述两种方法,提出分布式环境下基于数据扰乱技术的隐私保护方法,支持高效的分布式隐私保护数据挖掘.共谋攻击的实验结果和分析表明:匿名数据交换机制下的数据挖掘隐私保护方法在高密度共谋攻击的半诚实环境中有较好的鲁棒性,与主流的安全多方计算相比具有显著的效率优势;同时,该方法具有较高的灵活性和通用性,能应用于关联规则挖掘、聚类多种场合.

数据交换平台的分布式应用研究

为了使用户能够以一个整体来管理和调度企业内部众多的分布运行的数据交换平台,研究了数据交换平台需要着重解决的主要问题,设计了交换平台的多层级分布式应用模型,提出了在交换平台分布式应用环境中需要研究的三方面内容——元数据管理、平台管理和交换平台之间的通信。针对这3个方面内容进行了深入地探讨,提出了相应的解决方法。

基于SOAP的分布式构件集成研究

分布式构件技术提高了软件开发的效率,但各个构件的异构性也给应用软件的互操作性、兼容性以及平滑升级能力带来了问题,针对目前几种主要构件标准存在的缺陷,结合SOAP技术的发展,提出了一种基于SOAP的分布式异构构件集成模型,利用该技术能够灵活、透明、简便地集成各种分布式异构构件,实现异构构件自觉爱女的互操作。同时详细介绍了实现该模型的关键技术。

基于OPC技术的上位机监控软件设计

本文结合工程实例,介绍了基于OPC技术的上位机监控软件设计,详细讨论了该方法的具体应用。通过OPC接口,实现了上位机对运行CENTUM CS1000系统的PC机的数据采集。软件编程采用模块化的设计思想。上位机和下位机通过以太网通信,上位机可以实时地得到来自生产过程的数据。

分布式地质图空间数据库数据交换系统的设计与实现

分布式地质图空间数据库具有数据分布、数据源异构、地质实体间有着复杂语义关系的特点,而多源分布的地质图数据在实际应用中又需要统一管理,协调工作,这就提出了数据交换的要求。传统的数据库复制方案无法满足地质实体级的数据交换,本文提出了一种以地质空间要素类为交换单位的增量同步的数据交换设计方案,详细阐述了其关键的数据交换原理,数据传输方案以及上下级服务器之间的数据同步策略,该方案现已用于国家地质图空间数据库管理系统,被认为是一种行之有效的方案。