10 Gb/ s 0. 18 􀀁m CMOS 激光二极管驱动器芯片

基于0．18μm CMOS工艺设计的10Gb／s激光二极管驱动器电路。核心单元为两级直接耦合的差分放大器，电路中采用了并联峰化技术和放大级直接耦合技术以扩展带宽，降低功耗。模拟结果表明，在1．8V电源电压作用下该电路可工作在10Gb／s速率上，输入单端峰峰值为0．3V的差分信号时，在单端50Ω负载上的输出电压摆幅可达到1．4V，电路功耗约为85mW。     

用新的电路形式提高HBT光调制器驱动电路的传输速率及性能

在传统光调制器驱动电路中,所用HBT截止频率的大小要达到驱动电路传输速率的4倍以上.文中在输出级采用共射共基HBT形式后,其器件的截止频率只需大于电路传输速率的2倍即可,从电路设计的角度降低了对所用器件的要求.文中分析了新的电路结构提高传输速率的原因并给出了模拟结果.同时新的电路结构也具有良好的热稳定性.     

Hydrocarbon storage in unlined rock caverns in Greek limestone

The existence of tank farms in the vicinity of cities is a principal component of the urban vulnerability and risk conditions. Even if such environments have been accepted in the past, the enforcement of stricter environmental legislations and the emerging of a strong public opposition towards this co-existence, usually result in the relocation of the facilities. Nevertheless, the relocation process has to overcome a great deal of issues, such as high land cost and strong opposition from neighbouring communities, that often hinder or might even postpone the whole project. Answer to such standstill cases can be given by the development of underground complexes that can facilitate the storage requirements, efficiently and with enhanced environmental protection. Hence, the first area that should be considered for the tank farm relocation is found right beneath the existing facilities. This paper presents the Greek experience, paying special attention to the storage facilities found in the Perama area. The development of an underground storage complex is proposed in that particular area, which could finally offer a viable solution, satisfying the interests of all involved parties. The unlined caverns are to be excavated in limestone bedrock and the characteristics of this alternative are illustrated in detail, followed by the comparative cost analysis between the underground scheme and the surface relocation of the tank farm to another area in Attica.     

Cost effectiveness of decentralized energy supply systems taking solar and wind utilization plants into account

In this article, results are presented of annual simulations of a decentralized (regional) plant for the power and heat supply of a residential complex. This complex consists of four houses with 40 flats all in all. The annual power consumption of the complex is 157 MWh and the heat requirement is 325 MWh. The concrete dynamics of the energy demands over the year is taken into consideration. The energy supply system is composed of a power-controlled combined heat and power (CHP) plant (55 kW), a photovoltaic plant (PV array or PV plant) array for power generation as well as a field of solar thermal collectors with a short-term accumulator for water heating and a long-term accumulator for supplying heat for domestic heating purposes. Simulation results demonstrate that synergetic effects result from the combination of a CHP plant with wind power and PV plants of varying sizes, which have an effect on the cost effectiveness of the plant as a whole with the different dynamics of energy sources (wind and solar energies) and of the consumption of power and heat being the decisive factors. The power deficits of wind power and PV plants are compensated through the application of a natural gas-operated CHP plant. In almost all variants, the demand for fossil energy carriers is distinctly less than in conventional energy supply plants.     

Present status and future prospects of PV activities in Japan

The photovoltaic (PV) power systems in Japan made great strides in the past decade. The PV industry in the 1990s greatly depended on the research projects and dissemination programs carried out by the Ministry of International Trade and Industry. However, the industrial structure for full-scale deployment of the PV system is currently being established by the manufacturers’ continuous efforts to reduce the PV system cost and the government’s consecutive supports to create the initial market. It is expected that the synergetic effect of the cost reduction and incentives for introduction will activate the PV industry and its market more and more toward achieving 5000 MW of the capacity in FY 2010.     

由IR2155驱动的高功率因数电子镇流器

本文介绍了一种由ＩＲ２１５５驱动的电子镇流器功能特点和工作原理。     

Cost and sensitivity analysis for photovoltaic station in Kuwait

A full analysis is shown in this paper for the cost of kWh generated from photovoltaic station located in Kuwait. By using a 21 years weather data for Kuwait, the yearly generated energy was found by proposing the PV station capacity with known panels tilt angle. The cost of kWh generated from PV station was compared with the kWh generated from conventional units in the country. A sensitivity analysis was done to some factors; capital cost per installed PV peak watt, discount rate, and operating peak hours, which affect the cost of kWh production from both PV and conventional units. If the PV station is proposed to be installed in Kuwait, the capital cost per PV installed peak watt must be less than today's prices.     

地球同步轨道卫星表面电位探测一类方法初探

介绍了地球同步轨道卫星表面由于周遭的等离子体环境而造成的充电现象及其危害,并提出一类利用压电驱动式振动直接电场强度测量的表面电位测量方法。单一传感器可以测量卫星表面相对于卫星结构的电位差,多个传感器配合将可以测量卫星表面的不等电位差以及卫星表面相对太空环境的电位差。     

Cost estimation of structural skeleton using an interactive automation algorithm: A conceptual approach

This paper addresses a new concept for generating bills of quantities (B.o.Qs) using AutoCAD drawings for a building project, which demonstrates the application of Industry Foundation Class (IFC), developed by International Alliance for Interoperability (IAI). The procedure considers types of materials and the structural shapes of the AutoCAD drawings to compute the cost of the structural skeleton elements using interactive automation. The main concept focuses on using layer computation of the AutoCAD drawing after converting it into a drawing inter-exchangeable file format (DXF). Once the coordinates are detected, it is easier to determine the area and volume for any structural shape, including circles and polygons. The extracting method is a new technique for structural engineers and quantity surveyors to estimate required material for beam, columns, slabs and foundations. The algorithm extracts and recognizes the layers and objects from a two dimensional DXF drawing along with the coordinates information. The results obtained using this technique are more accurate and reliable than manual procedures or any other traditional techniques. In this paper, an automated and interactive procedure for B.o.Q computation is demonstrated. The process involves a user-friendly interface, dynamic linking to the structural drawings and tracking of B.o.Q modifications at the same time.