To this day, Power over Ethernet (PoE) continues to gainpopularity in today’s networking world. The 12.95Wdelivered to the Powered Device (PD) input supplied bythe Power Sourcing Equipment (PSE) is a universal supply.Each PD provides its own DC/DC conversion from anominal 48V supply, thus eliminating the need for a correctvoltage wall adapter. However, higher power devicescan not take advantage of standard PoE because of itspower limitations, and must rely on a large wall adapteras their primary supply. The new LTC4268-1 breaks thispower barrier by allowing for power of up to 35W for suchpower-hungry 2-pair PoE applications. The LTC4268-1provides a complete solution by integrating a high powerPD interface control with an isolated fl yback controller.
Avalanche photo diode (APD) receiver modules arewidely used in fi ber optic communication systems. AnAPD module contains the APD and a signal conditioningamplifi er, but is not completely self contained. It stillrequires signifi cant support circuitry including a highvoltage, low noise power supply and a precision currentmonitor to indicate the signal strength. The challenge issqueezing this support circuitry into applications withlimited board space. The LT®3482 addresses this challengeby integrating a monolithic DC/DC step-up converter andan accurate current monitor. The LT3482 can supportup to a 90V APD bias voltage, and the current monitorprovides better than 10% accuracy over four decades ofdynamic range (250nA to 2.5mA).
As environmental concerns over traditional lighting increaseand the price of LEDs decreases, high power LEDsare fast becoming a popular lighting solution for offl ineapplications. In order to meet the requirements of offl inelighting—such as high power factor, high effi ciency, isolationand TRIAC dimmer compatibility—prior LED driversused many external discrete components, resulting incumbersome solutions. The LT®3799 solves complexity,space and performance problems by integrating all therequired functions for offl ine LED lighting.
為了改變目前電網現場作業管理的變電巡檢、變電檢修試驗、輸電線路巡檢檢修等管理系統各自獨立運行,信息不能共享,功能、效率受限,建設和維護成本高的現狀,提出了采用B/S+C/S構架模式,將各現場作業管理模塊和生產MIS(管理系統)集成為一體的現場作業管理系統的設計方案,做到各子系統和生產MIS軟硬資源共享,做到同一數據唯一入口、一處錄入多處使用。各子系統設備人員等基礎信息來源于生產管理系統,各子系統又是生產管理系統的作業數據、缺陷信息的重要來源。經過研究試用成功和推廣應用,目前該系統已在江西電網220 kV及以上變電站全面應用。
Abstract:
In order to improve the status that the substation field inspection system, substation equipments maintenance and testing system, power-line inspection and maintenance system are running independent with each other. They can?蒺t share the resource information which accordingly constrains their functions and efficiency, and their construction and maintenance costs are high. This paper introduces a field standardized work management system based on B/S+C/S mode, integrating all field work management systems based on MIS and share the equipments and employee?蒺s data of MIS,the field work data of the sub systems are the source information of MIS, by which the same single data resouce with one-time input can be utilized in multiple places. After the research and testing, this system is triumphantly using in all 220kV and above substations in Jiangxi grid.
In the past decade, the size and complexity of manyFPGA designs exceeds the time and resourcesavailable to most design teams, making the use andreuse of Intellectual Property (IP) imperative.However, integrating numerous IP blocks acquiredfrom both internal and external sources can be adaunting challenge that often extends, rather thanshortens, design time. As today's designs integrateincreasing amounts of functionality, it is vital thatdesigners have access to proven, up-to-date IP fromreliable sources.
In the past decade, the size and complexity of manyFPGA designs exceeds the time and resourcesavailable to most design teams, making the use andreuse of Intellectual Property (IP) imperative.However, integrating numerous IP blocks acquiredfrom both internal and external sources can be adaunting challenge that often extends, rather thanshortens, design time. As today's designs integrateincreasing amounts of functionality, it is vital thatdesigners have access to proven, up-to-date IP fromreliable sources.
ARM7硬件說明與開發
The ARM7 is a low-power, general purpose 32-bit RISC microprocessor macrocell for use in application or
customer-specific integrated circuts (ASICs or CSICs). Its simple, elegant and fully static design is
particularly suitable for cost and power-sensitive applications. The ARM7’s small die size makes it ideal for
integrating into a larger custom chip that could also contain RAM, ROM, logic, DSP and other cells.
Abstract
The Lucene Server project is an attempt to extend the Jakarta Lucene tool with server capabilities.
Lucene is a robust Java API that enables you creating indexes from text sources and perform powerful searches on these indexes. With Lucene, creating an index must be done programmatically and there are almost no possibilities of integrating index management in a distributed environment. In other words, out of the box, Lucene is suitable for integrating indexing and searching possibilities in a single application but not for providing index/search services for multiple applications.
The Lucene Server project comes with a Java API that propose the following
make it easy to create indexes in a declarative way by simply providing an XML configuration document.
make it easy to personalize the way Lucene must handle different kind of data sources.
provide services for index management and searching that can be accessed from several applications.
enable batch tasks scheduling.