油田信息自动采集系统的设计与实现

以嵌入式系统及GPRS、TD-SCDMA无线传输技术及B/S设计架构技术为基础,研制开发了油田开采信息自动采集系统.通过嵌入式系统实现数据实时检测,通过无线传输网络自动加载数据到公司信息中心实时数据库,为各级管理部门提供开放的数据平台,使生产和管理人员及时了解和控制生产动态,达到提高生产过程自动化、实现节能降耗、减员增效的功能和目的,为降低生产成本提供重要依据,为油田实现自动化监控奠定基础.本系统已在大港、新疆、长庆等油田成功应用.     

动态口令认证技术在计量自动化终端数据通信安全中的应用探讨简

在计量自动化系统建设实施时通过分析了系统主站与现场终端之间的数据通信全过程,对GPRS通信的计量自动化终端在数据传输过程中存在的安全性问题进行了探讨,提出将动态口令身份认证技术用于终端数据通信传输的设想和方案,提高主站系统与现场终端数据在传输过程中的安全性。     

动态口令认证技术在计量自动化终端数据通信安全中的应用探讨

在计量自动化系统建设实施时通过分析了系统主站与现场终端之间的数据通信全过程,对GPRS通信的计量自动化终端在数据传输过程中存在的安全性问题进行了探讨,提出将动态口令身份认证技术用于终端数据通信传输的设想和方案,提高主站系统与现场终端数据在传输过程中的安全性。     

OPC技术在油田优化监控系统中的应用研究

针对远程监控系统的发展趋势和目前工业控制中对实时传输的实际要求,OPC技术提供了标准化访问接口,应用程序可以使用一致的方式访问设备中的数据。本文研究了油田优化监控系统的总体结构,并通过OPC客户端将WinCC中的实时数据转储到SQL数据库中,解决了组态软件中实时数据转储到标准数据库的难题,最后给出了OPC客户端的实现过程。     

基于CART的焦化生产实时数据库设计

研究钢铁企业焦化生产实时数据采集系统,针对过程控制系统中的海量数据,设计基于CART数据库平台的焦化生产实时数据库系统,并给出具体实现方法。系统利用数据接口程序采集过程控制中的实时数据,通过办公局域网实现数据的传输与多用户共享,利用CART数据库平台实现生产实时数据的访问及管理应用。在实现过程中采用DDE、OPC、多线程、Windows服务等多种技术,保证了软件的实时性。     

煤矿排水自动控制系统的设计与研究

为了提高煤矿自动化生产的水平,降低工人劳动强度,提高信息传输及分析能力,在原有主排水设施基础上进行自动化改造,实现了设备在无人干涉情况下的自动运行和自我诊断,使设备达到最佳运行状态。该系统采用PLC控制,通过相关传感器采集水泵运行数据,对水泵及关联设备进行实时监测与控制,同时将数据上传到煤矿调度中心,实现了煤矿主排水系统的远程监测与控制,满足煤矿生产环境及安全生产的需要。     

煤层气地面记录仪设计与监控系统开发

为了满足构造煤煤层气开发过程中的自动化实时监测任务,该文设计了一种低功耗地面记录仪,并在此基础上开发了煤层气监控系统。该地面记录仪采用低功耗STM32L433RC作为主控制器,搭配MAX485EN接口芯片以及W25Q64存储芯片,采用485总线传输以及Modbus串行通信协议,通过主从站任务转换,实现了数据的实时传输处理与服务器存储。上位机采用组态王软件编程。所设计的煤层气开采监控系统,具有低耦合、多设备、高集成等特点,提高了煤层气开采的自动化程度。最后,实验结果表明所设计的低功耗地面记录仪能够有效地上传传感器数据,且可与多仪器完成数据通讯,满足实际需求。     

力控在大宗物料计量管理中的应用

通过近几年的计算机软硬件领域的发展、控制和管理方法的突破,CIMS在炼油、化纤、化肥、化工等流程工业领域里的应用,可以提高企业经济效益。CIMS的重点是在集成下列6个自动化系统:生产过程控制DCS;生产过程实时监测及实时数据库系统;生产过程流程模拟、先进控制、优化控制;管理信息MIS系统;办公自动化系统、经营规划及经营决策分析。1系统需求为了使大宗物料计算机管理上一个新的台阶,本方案把生产过程自动化中的计量数据与管理系统、办公自动化系统有机连接起来,使管理层合理利用信息资源,把庞大的生产过程信息、企业内部管理信息、…     

远程通信在油田上的应用研究

油田生产系统含有H2S、CO2和水等腐蚀介质,均存在内腐蚀问题。由于腐蚀问题引起的事故常有发生,严重威胁人生安全,同时也给企业带来巨大经济损失。于是在油田生产系统中应用腐蚀在线监测实行实时监测显得越发重要。根据实时监控传输到上位机中的参数采取相应防护措施,从而预防和控制腐蚀的发生,本文通过将采集到的数据能够实时显示并存储一定量的离线数据,最后通过RS-485接口与上位机软件进行通信,将腐蚀仪当中的数据传输到计算机中存储及分析。最终通过采集到的数据获取腐蚀速率等相关的数据并实现加药泵的自动投放,大大地提高了腐蚀监测系统的自动化程度。     

无线局域网技术在锅炉承压管管外检测机器人中的应用

在本机器人系统中，利用无线局域网技术，成功地解决了数据在无线传输过程中的屏 蔽现象以及控制信号和视频信号在同一频道实时传输的问题；文章还就机器人的通讯过程以 及控制信号在传输过程中遇到的问题进行了详细讨论，制定了通讯协议．     

绝对式光电轴角编码器CAN总线接口

针对绝对式光电轴角编码器在采用CAN总线通信方式控制系统中的应用，提出编码器数据传输接口的一种新方法。即通过CAN总线接口实现在带有多传感器、多分系统的控制系统中数据传输，本文论述了它在大型光电跟踪系统中的应用。     

蜜罐取证的技术及法律问题研究

蜜罐作为新兴的网络防御及动态取证技术,不仅能够主动防御网络攻击,而且还可以收集入侵者实施攻击的重要证据。它通过网络欺骗、端口重定向、报警、数据控制和数据捕获等技术,增强动态防护体系的检测与反应能力,提高网络的安全防护水平。蜜罐运行会产生一定的技术风险,而选择低风险蜜罐、强化系统的数据获取和报警功能以及增加连接控制和路由控制等能有效实现风险控制。对于蜜罐取证可能产生的陷阱、隐私权及责任等法律问题,则可采取避免过度主动引诱、隐私权提示及审慎监控等方式加以克服。     

A security flow control algorithm and its denotational semantics correctness proof

We derive a security flow control algorithm for message-based, modular systems and prove the algorithm correct. The development is noteworthy because it is completely rigorous: the flow control algorithm is derived as an abstract interpretation of the denotational semantics of the programming language for the modular system, and the correctness proof is a proof by logical relations of the congruence between the denotational semantics and its abstract interpretation. Effectiveness is also addressed: we give conditions under which an abstract interpretation can be computed as a traditional iterative data flow analysis, and we prove that our security flow control algorithm satisfies the conditions. We also show that symbolic expressions (that is, data flow values that contain unknowns) can be used in a convergent, iterative analysis. An important consequence of the latter result is that the security flow control algorithm can analyse individual modules in a system for well formedness and later can link the analyses to obtain an analysis of the entire system.     

绝对式光电轴角编码器CAN总线接口

针对绝对式光电轴角编码器在采用CAN总线通信方式控制系统中的应用,提出编码器数据传输接口的一种新方法,即通过CAN总线接口实现在带有多传感器、多分系统的控制系统中数据传输,本文论述了它在大型光电跟踪系统中的应用。     

An efficient PHR service system supporting fuzzy keyword search and fine-grained access control

Outsourcing of personal health record (PHR) has attracted considerable interest recently. It can not only bring much convenience to patients, it also allows efficient sharing of medical information among researchers. As the medical data in PHR is sensitive, it has to be encrypted before outsourcing. To achieve fine-grained access control over the encrypted PHR data becomes a challenging problem. In this paper, we provide an affirmative solution to this problem. We propose a novel PHR service system which supports efficient searching and fine-grained access control for PHR data in a hybrid cloud environment, where a private cloud is used to assist the user to interact with the public cloud for processing PHR data. In our proposed solution, we make use of attribute-based encryption (ABE) technique to obtain fine-grained access control for PHR data. In order to protect the privacy of PHR owners, our ABE is anonymous. That is, it can hide the access policy information in ciphertexts. Meanwhile, our solution can also allow efficient fuzzy search over PHR data, which can greatly improve the system usability. We also provide security analysis to show that the proposed solution is secure and privacy-preserving. The experimental results demonstrate the efficiency of the proposed scheme.     

Role-Based Access Control in a Data Grid Using the Storage Resource Broker and Shibboleth

In this paper, we propose a role-based access control (RBAC) system for data resources in the Storage Resource Broker (SRB). The SRB is a Data Grid management system, which can integrate heterogeneous data resources of virtual organizations (VOs). The SRB stores the access control information of individual users in the Metadata Catalog (MCAT) database. However, because of the specific MCAT schema structure, this information can only be used by the SRB applications. If VOs also have many non-SRB applications, each with its own storage format for user access control information, it creates a scalability problem with regard to administration. To solve this problem, we developed a RBAC system with Shibboleth, which is an attribute authorization service currently being used in many Grid environments. Thus, the administration overhead is reduced because the role privileges of individual users are now managed by Shibboleth, not by MCAT or applications. In addition, access control policies need to be specified and managed across multiple VOs. For the specification of access control policies, we used the Core and Hierarchical RBAC profile of the eXtensible Access Control Markup Language (XACML); and for distributed administration of those policies, we used the Object, Metadata and Artifacts Registry (OMAR). OMAR is based on the e-business eXtensible Markup Language (ebXML) registry specifications developed to achieve interoperable registries and repositories. Our RBAC system provides scalable and fine-grain access control and allows privacy protection. Performance analysis shows that our system adds only a small overhead to the existing security infrastructure of the SRB.     

安全访问控制系统的设计和实现

访问控制是现代企业信息系统设计的核心,它控制用户行为,保护系统资源的安全。传统的访问控制模块的设计与应用系统紧密耦合,使其无法得到很好的复用。本文介绍了轻量级目录访问控制协议(LightweightDirectoryAccessProtocol,简称LDAP)和基于角色的访问控制基于角色的访问控制(Role-basedAccessControl,简称RBAC)模型,基于它们设计了一个高效、安全的访问控制系统。该系统在省邮政综合服务平台中的到应用,有效解决了原有系统设计中的一些弊端。     

Depth recovery and affine reconstruction under camera pure translation

This paper addresses the problems of depth recovery and affine reconstruction from two perspective images, which are generated by an uncalibrated translating camera. Firstly, we develop a new constraint that the homography for the plane, which is orthogonal to the optical axis, is determined only by the epipole and the plane's relative distance to the origin under camera pure translation. The algorithm of depth recovery is based on this new constraint, and it can successfully avoid the step of camera calibration. With the recovered depth, we show that affine reconstruction can be obtained readily. The proposed affine reconstruction does not need any control points, which were used to expand the affine coordinate system in existing method. Therefore, it could avoid the step of non-planarity verification as well as the errors from the control points. Error analysis is also presented to evaluate the uncertainty for the recovered depth value. Finally, we have tested the proposed algorithm with both simulated data and real image data. And the results show that the proposed algorithm is accurate and practical.     

REMUDA: 一个实用地无线传感网络拓扑控制和数据转发机制

In wireless sensor networks, topology control plays an important role for data forwarding efficiency in the data gathering applications. In this paper, we present a novel topology control and data forwarding mechanism called REMUDA, which is designed for a practical indoor parking lot management system. REMUDA forms a tree-based hierarchical network topology which brings as many nodes as possible to be leaf nodes and constructs a virtual cluster structure. Meanwhile, it takes the reliability, stability and path length into account in the tree construction process. Through an experiment in a network of 30 real sensor nodes, we evaluate the performance of REMUDA and compare it with LEPS which is also a practical routing protocol in TinyOS. Experiment results show that REMUDA can achieve better performance than LEPS.     

Parameter set estimation for non-linear systems

Models of dynamical systems are instrumental for many purposes: prediction, control, simulation, tracking and so on. In this paper, we will show how parameter set estimation (PSE) can be applied to non-linear systems. Parameter set estimation identifies a set of estimates which are feasible with respect to the measured data and a priori information. This set of parameters, feasible for the given model structure, can then be used for system tracking or robust control designs. For application to robust control, it is important that the size of this set be as small as possible. In order to apply parameter set estimation techniques to a non-linear system, the system function is expressed in a tensor parameterization which is linear in the parameters (LP). Then it is shown how an optimum volume ellipsoid strategy for linear time invariant systems can be extended to this tensor parameterization of a non-linear system. The methodology is illustrated on two examples, the second of which uses data obtained from an operating glass furnace.