954 resultados para Winsock API
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空间数据管理和维护技术是卫星数据应用系统的关键技术之一,对于推动卫星数据应用的发展有不可或缺的重要意义。本文在分析数据管理的各种先进技术的基础上,设计了卫星地面应用系统中的数据管理维护解决方案;讨论了该解决方案的具体设计实现。主要工作有:一、 系统架构:本文设计了层次式的系统架构,将系统从上到下分为数据应用层、数据访问接口层、逻辑数据层、物理数据层等,并对各层之间的功能和之间的交互做了明确定义。二、 数据统一访问:本文设计了数据访问接口层,向下层负责操作逻辑数据,向上层用户提供一个易用的统一的数据访问接口。该接口层屏蔽了底层数据格式和存储等差异,支持数据的统一存取,提供透明的数据访问,降低了系统之间的耦合度。三、 数据操作实现:本文基于XML设计了数据用户和数据管理维护系统之间数据交换的格式。在数据访问接口层实现了从XML格式请求到SQL语句(或文件API调用)的转换逻辑以实现各种数据操作请求,提高了系统可扩展性。论文还设计了多种数据安全方法相结合的数据安全策略,提高了系统中数据的安全性。数据管理维护系统的开发和测试过程表明,该方案基本满足卫星地面应用系统中数据管理和维护的需求。
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In the organic-inorganic perovskites family, the < 100 >-oriented type has been extensively investigated as a result of its unique magnetic, optical, and electrical properties, and only one type of < 110 >-oriented hybrid perovskite stabilized by methylammonium and iodoformamidinium cations or the latter themselves has been known so far. In this paper, another novel < 110 >-oriented organic-inorganic perovskite (C6H13N3)-PbBr4 (compound 1) has been prepared by reacting N-(3-aminopropyl)imidazole (API) with PbBr2 in hydrobromic acid. The crystal structure is determined, which indicates that the perovskite is stabilized by API. The introduction of the optically active organic ligand API into the hybrid perovskite results in a red shift and a great enhancement of photoluminescence in the perovskite with respect to organic ligand API itself. These results have been explained according to calculation based on density-functional theory. Moreover, the excellent film processing ability for the perovskite (C6H13N3)PbBr4 together with the improved optical properties makes it have potential application in optoelectronic devices.
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海洋设施长期处于恶劣的腐蚀环境中,如不加以防护,一旦发生应力腐蚀开裂(SCC),损失就会极为惨重。海底泥土区环境十分重要,因为管线和平台桩腿等都埋在海底泥中。海底泥中硫酸盐还原菌(SRB)十分活跃,而且为了防止腐蚀,海泥中的设施无一例外地采取了阴极保护,相当于设施处在长期稳定的充氢状态。因此非常有必要研究海泥中的活性SRB和极化电位对海洋结构用钢在海泥中的氢渗透行为和SCC敏感性造成的影响,弄清SCC发生和发展的过程以便采取相应的措施减缓或防止SCC。 本文通过慢应变速率拉伸实验(SSRT)、电化学阻抗谱(EIS)技术、动电位扫描极化曲线测定实验和氢渗透实验等研究了海泥中SRB和极化电位对16Mn钢和管线钢X56(API X56)的SCC敏感性造成的影响。 从渤海海泥中富集得到SRB菌种,并做出了SRB在海泥中的生长曲线;在荧光显微镜下观察SRB为弧状,可以归为脱硫弧菌属,为革兰氏阴性菌;海泥中活性SRB数量与硫电位等主要腐蚀环境因子具有一定的对应关系。 SSRT结果表明,施加阴极极化电位可以使试样断裂脆性特征明显,SCC敏感性增大;海泥中活性SRB浓度越高,断裂脆性特征越明显,SCC敏感性越大。在含SRB海泥中或阴极极化电位条件下,两种钢都容易发生SCC,氢脆(HIC)起主要作用。 随着浸泡天数的增加,试样在灭菌海泥中的Rp一直增大;在含SRB海泥中Rp先增大,又变小,并呈现出显著的Warburg阻抗特征;在灭菌海泥中,两种试样在阳极电位范围内无SCC敏感区,而在阴极电位范围内有明显的SCC敏感区;在含SRB海泥中,在阳极电位范围和阴极电位范围内均有SCC敏感区;SRB代谢产物既有阳极去极化作用,又有阴极去极化作用,能使腐蚀电流密度增加。 活性SRB的存在能够促进试样在海泥中的氢渗透;在实海工程应用中,两种钢在含SRB海泥中的氢渗透电流密度大约是在不含SRB海泥中的3~4倍。阴极极化电位能够促进试样在灭菌海泥中的氢渗透。在含SRB海泥中对试样施加阴极极化电位,氢渗透电流密度大于不加阴极极化电位时的氢渗透电流密度,也大于在不含SRB的海泥中的氢渗透电流密度。
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Research on corrosion of steel structures in various marine environments is essential to assure the safety of structures and can effectively prolong their service life. In order to provide data for anticorrosion design of oil exploitation structures in the Bohai Bay, the corrosion behaviour and properties of steel in beach soil, using typical steel samples (Q235A carbon steel and API 5Lx52 pipeline steel) buried 0.5, 1.0 and 1.5 m deep under typical beach soils in Tanggu, Yangjiaogou, Xingcheng, Yingkou and Chengdao for 1-2 years were studied. The carbon steel and pipeline steel were both corroded severely in the beach soil, with the form of corrosion being mainly uniform with some localised attack (pitting corrosion). The corrosion rate of the carbon steel was up to 0.16 mm/year with a maximum penetration depth of 0.76 mm and that of the pipeline steel was up to 0.14 mm/year, with a maximum penetration depth of 0.53 mm. Compared with carbon steel, the pipeline steel generally had better corrosion resistance in most test beach soils. The corrosion rates and the maximum corrosion depths of carbon steel and pipeline steel were in the order: Tanggu>Xingcheng>Chengdao>Yingkou>Yangjiaogou with corrosion altering with depth of burial. The corrosion of steel in the beach soil involves a mixed mechanism with different degrees of soil aeration and microbial activity present. It is concluded that long term in situ plate laying experiments must be carried out to obtain data on steel corrosion in this beach soil environment so that the effective protection measures can be implemented.
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现代计算机软硬件技术、计算机图形技术高速发展,以及数字仿真技术的广泛应用,为工业机器人离线编程技术的实际应用提供了有利条件。同时,现代生产的高效率、柔性化需求也促使了工业机器人离线编程软件产品的产生。机器人离线编程系统,是利用计算机图形学技术,建立起机器人及其工作环境的模型,利用机器人语言及相关算法,通过对图形的控制和操作在离线的情况下进行轨迹规划。离线编程技术具有传统的在线示教技术无法比拟的优势,比如:可减少停机时间、可提前验证作业程序,进行复杂的轨迹规划等。 国外的机器人离线编程软件功能已经很强大,但是只是针对特有的机器人,还不能做到像办公软件那样通用化。新松机器人公司是国内为数不多的具有自主开发工业机器人能力的公司之一,已成功开发了多款工业机器人产品,为开发自己的离线编程软件提供了客观条件,也提出了客观需求。以此为背景,本文按照软件工程的设计思想,设计了离线编程软件的框架,详细阐述了各个模块的设计原理、运行流程,对涉及到的关键技术问题,从理论、实践两个方面做了较为详细的介绍。最后,针对各个功能做了验证工作。离线编程软件系统,首先需要一个虚拟的3D仿真环境,通过该虚拟仿真环境,显示机器人的运动效果,同时为作业编程点的获取提供可视化的环境。为了提高虚拟仿真的真实程度,需要实现碰撞检测功能,并且精度和速度都要满足要求。为了便于操纵虚拟机器人,需要一个模拟示教盒的软件,以及虚拟控制器软件。为了实现多个软件之间的协作,需要传递控制流与数据流数据。 本文主要解决了整个离线编程软件系统开发过程中遇到的下列问题: (1)3D图形仿真环境的建立。本设计采用了OpenGL作为底层的图形API,并对图形显示模块做了封装,提供一组简单、方便的接口。 (2)数据结构的定义和资源管理。涉及到图形资源、抽象的仿真对象资源。为了实现多个类型的机器人能在同一仿真环境下运行,需要建立一个机器人类型库,采用了基于“抽象工厂设计”这种设计模式解决这个问题。 (3)基于3D空间的碰撞检测技术。主要采用了基于AABB包围盒和分离轴检测的技术(SAT),实现两级计算,先粗后精。 (4)仿真环境和实际环境之间的工件标定技术。 (5)虚拟作业的建立。包括根据矩阵方法用鼠标选取操作来获取示教点,设计虚拟示教盒软件,生成作业文件。 (6)多个软件之间的通信及协议制定。
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详细阐述利用VB6.0进行SolidWorks二次开发的关键技术,论述斜齿轮的三维参数化建模系统开发的具体过程,对比了不同建模方法的特点,提出齿轮三维建模误差分析的两种方法,为模型应用提供了理论指导,同时对该研究方法的拓展性应用举出实例,给出用VB开发SolidWorks一般方法。
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为了实现定位抓取任务,提出基于网络的直角坐标机器人视觉控制系统。针对机器人运动控制的非线性与强耦合特性,采用神经网络控制器,构建了图像偏差与运动控制量之间的对应关系。通过对图像增强、边缘提取、特征提取等图像处理方法的综合分析,提出了一套优化组合图像处理法。在计算机网络环境下,采用自定义协议实现图像处理器与运动控制器协调控制,并将远程监控应用到机器人控制中。实验结果表明,该系统能够在视野范围内自动实现定位抓取动作。
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本文针对异构分布环境下的多机器人系统 ,提出了一种基于 CORBA规范和框架请求代理 (FRB)这一方式的应用系统集成模型 .为实现分布异构环境下的多机器人的通信、协同、编程 ,支持系统任务重组与重构、应用互操作提供一条有效途径 .并给出了一个自行设计的面向多机器人基于CORBA的对象互操作的方法、机制 .给出基于 CORBA的应用编程接口 (API)与扩展接口定义语言X- IDL,通过基于 CORBA的多机器人基本对象类的建立与对象的实现 ,实现基于 CORBA的多机器人互操作与开放分布处理原型系统 .
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Under the auspices of the 'knowledge-Innovation Program' of CAS, Institute of Geology and Geophysics has established the Broadband Seismic Laboratory. A new kind of 24-bit high-resolution seismograph DAS24-3B has been designed and manufactured in an effort of developing China's own technology of seismic array. Since these instruments will primarily be used in field operation, there is a need to optimize the system software of data acquisition system (DAS) to enhance its stability, compatibility and maintenance. The design ideas of the system software of DAS24-3B are partly learned from the advanced DAS 72A-08. In this system there are two exclusive communication programs DNAPI-COM1 and DNAPI-LPT1, which are suitable for all standard industrial computers with ECP parallel port and serial port. By these exclusive parallel and serial communication interface the system software is split into three parts, acquisition program, user's control program and graphical display program, which can function well in separate units and can run correctly in whole. The three parts of DAS24-3B's system software possess different functions and advantages. The function of acquisition program is to control the process of seismic data acquisition. DAS24-3B system reduced its power and harddisk read-write disturbance by using the extended memory attached to its CPU, which functions as enlarging the data buffer of system and lessening the times of harddisk read-write operations. Since GPS receiver of DAS is strongly sensitive to the around environment and has the possibility of signal loss the acquisition program has been designed with the ability to automatically trail the GPS locked time. The function of user's controlling program is to configure the system's work environment, to inform the user's commands to DAS, to trail the status of DAS in real-time. The function of graphical display program is to illustrate data in figures, to convert data file into some common formatted file, to split data file in parts and combine data files into one. Both user's control program and graphical display program are API (Application Programming Interface) in window 95/98 system. Both possess the features of clearness and friendship by use of all kind of window controls, which are composed by menu, toolbar, statusbar, dialogue box, message box, edit box, scrollbar, time control, button and so on. Two programs of systemic exception handles are provided to treat the trouble in field. The DAS24-3B DAS has been designed to be easier to use-better ability, more stable and simpler. It has been tested in field and base station and has been proved more suitable for field operation of seismic array than other native instruments.
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Statistical Rate Monotonic Scheduling (SRMS) is a generalization of the classical RMS results of Liu and Layland [LL73] for periodic tasks with highly variable execution times and statistical QoS requirements. The main tenet of SRMS is that the variability in task resource requirements could be smoothed through aggregation to yield guaranteed QoS. This aggregation is done over time for a given task and across multiple tasks for a given period of time. Similar to RMS, SRMS has two components: a feasibility test and a scheduling algorithm. SRMS feasibility test ensures that it is possible for a given periodic task set to share a given resource without violating any of the statistical QoS constraints imposed on each task in the set. The SRMS scheduling algorithm consists of two parts: a job admission controller and a scheduler. The SRMS scheduler is a simple, preemptive, fixed-priority scheduler. The SRMS job admission controller manages the QoS delivered to the various tasks through admit/reject and priority assignment decisions. In particular, it ensures the important property of task isolation, whereby tasks do not infringe on each other. In this paper we present the design and implementation of SRMS within the KURT Linux Operating System [HSPN98, SPH 98, Sri98]. KURT Linux supports conventional tasks as well as real-time tasks. It provides a mechanism for transitioning from normal Linux scheduling to a mixed scheduling of conventional and real-time tasks, and to a focused mode where only real-time tasks are scheduled. We overview the technical issues that we had to overcome in order to integrate SRMS into KURT Linux and present the API we have developed for scheduling periodic real-time tasks using SRMS.
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BACKGROUND: Scientists rarely reuse expert knowledge of phylogeny, in spite of years of effort to assemble a great "Tree of Life" (ToL). A notable exception involves the use of Phylomatic, which provides tools to generate custom phylogenies from a large, pre-computed, expert phylogeny of plant taxa. This suggests great potential for a more generalized system that, starting with a query consisting of a list of any known species, would rectify non-standard names, identify expert phylogenies containing the implicated taxa, prune away unneeded parts, and supply branch lengths and annotations, resulting in a custom phylogeny suited to the user's needs. Such a system could become a sustainable community resource if implemented as a distributed system of loosely coupled parts that interact through clearly defined interfaces. RESULTS: With the aim of building such a "phylotastic" system, the NESCent Hackathons, Interoperability, Phylogenies (HIP) working group recruited 2 dozen scientist-programmers to a weeklong programming hackathon in June 2012. During the hackathon (and a three-month follow-up period), 5 teams produced designs, implementations, documentation, presentations, and tests including: (1) a generalized scheme for integrating components; (2) proof-of-concept pruners and controllers; (3) a meta-API for taxonomic name resolution services; (4) a system for storing, finding, and retrieving phylogenies using semantic web technologies for data exchange, storage, and querying; (5) an innovative new service, DateLife.org, which synthesizes pre-computed, time-calibrated phylogenies to assign ages to nodes; and (6) demonstration projects. These outcomes are accessible via a public code repository (GitHub.com), a website (http://www.phylotastic.org), and a server image. CONCLUSIONS: Approximately 9 person-months of effort (centered on a software development hackathon) resulted in the design and implementation of proof-of-concept software for 4 core phylotastic components, 3 controllers, and 3 end-user demonstration tools. While these products have substantial limitations, they suggest considerable potential for a distributed system that makes phylogenetic knowledge readily accessible in computable form. Widespread use of phylotastic systems will create an electronic marketplace for sharing phylogenetic knowledge that will spur innovation in other areas of the ToL enterprise, such as annotation of sources and methods and third-party methods of quality assessment.
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The aim of this highly novel study was to use hot-melt extrusion technology as an alternative process to enteric coating. In so doing, oral dosage forms displaying enteric properties may be produced in a continuous, rapid process, providing significant advantages over traditional pharmaceutical coating technology. Eudragit (R) L100-55, an enteric polymer, was pre-plasticized with triethyl citrate (TEC) and citric acid and subsequently dry-mixed with 5-aminosalicylic acid, a model active pharmaceutical ingredient (API), and an optional gelling agent (PVP (R) K30 or Carbopol (R) 971P). Powder blends were hot-melt extruded as cylinders, cut into tablets and characterised using powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC) and dissolution testing conducted in both pH 1.2 and pH 6.8 buffers. Increasing the concentration of TEC significantly lowered the glass transition temperature (T,) of Eudragit (R) L100-55 and reduced temperatures necessary for extrusion as well as the die pressure. Moreover, citric acid (17% w/w) was shown to act as a solid-state plasticizer. HME tablets showed excellent gastro-resistance, whereas milled extrudates compressed into tablets released more than 10% w/w of the API in acidic media. Drug release from HME tablets was dependent upon the concentration of TEC, the presence of citric acid, PVP K30, and Carbopol (R) 971P in the matrix, and pH of the dissolution media. The inclusion of an optional gelling agent significantly reduced the erosion of the matrix and drug release rate at pH 6.8; however, the enteric properties of the matrix were lost due to the formation of channels within the tablet. Consequently this work is both timely and highly innovative and identifies for the first time a method of producing an enteric matrix tablet using a continuous hot-melt extrusion process.