Nuclear incident could prompt more costly inspections [power plants]

On 7 May 2002, the U.S. Nuclear Regulatory Commission (NRC, Rockville, Md.) formally heard the operator of an Ohio reactor report on the causes of a situation that could very nearly have led to a serious loss-of-coolant accident. The situation is now fairly well understood and can be considered isolated, but questions remain as to whether nuclear surveillance both by the NRC and plant operators is as rigorous as it needs to be.     

Digging for gold [data management]

The computer age promised to deliver information at the push of a button wherever it was needed. Instead it produces mounds of data, mostly worthless for any given purpose, requiring complex queries to extract relevant information. In the past, businesses failed to solve problems through lack of available data; nowadays the problem is more often too much data. The challenge is to find ways of distilling large volumes of data into valuable information. Most companies put far more information into their computers than they are ever likely to take out of them. Here, the authors describe how data mining offers a quick and efficient way of extracting those items that are useful     

A matter of trust [data security]

Larger amounts of information are being exchanged by electronic means. This has many advantages, including speed and convenience, but is by no means problem free. Most forms of electronic communication (not least the Internet) are not inherently secure. Security needs vary between applications, but common requirements include ensuring the information is not changed in transit and protecting the information against unauthorised disclosure. Ensuring security for electronic information exchange is far from straightforward and there is a danger that this problem could form a significant barrier to the growth of electronic commerce. Cryptography is one method of addressing the security weaknesses, but there is a difficulty in the management of the various keys. As the demand for secure electronic communications has grown, especially in the domain of electronic commerce, new institutions, often known as trusted third parties are emerging to meet this need. Trusted third parties could become key players in ensuring the security of electronic communications. The author explains the nature of these novel organisations and discusses some of the issues associated with their development     

A foggy notion [solar photovoltaic power system]

When completed, the Bavarian Solarpark will count as one of the largest photovoltaic power plants in the world. With 57,600 solar panels covering a total of 25 hectares of farmland, the 10-megawatt peak station actually consists of three collector installations located within a 50 km radius. While the plant is expected to partially replace Germany's nuclear and fossil fuel power plants with homegrown solar PV plants, the losses due to transmission of central station solar power negate the benefits enjoyed by users of on-site solar generation. The ultimate goal, however, is to foster the growth of a global PV industry and to count on economies of scale to bring the price of PV down to levels that even developing countries can afford.     

A relational database for semiconductor device parametric data

Semiconductor device parametric test data collected by lot, wafer, and die form a hierarchical data structure that lends itself to two relational models reflecting two data views. The two models may be integrated by carefully considering relationships, and the resultant structure is applicable to in-process data collection. Semiconductor device parametric data models are discussed from the two viewpoints, and a practical database based on the set-theoretic relational data model is developed. Application of the developed model to semiconductor in-process and functional test data is also discussed     

A model for system reliability with common-cause failures

A model for the analysis of systems subject to common-cause failures is proposed. The system consists of a finite number of components that are subject to: (1) statistically independent failures, and (2) external failure causes (they need not be mutually statistically independent) for groups of components. Applications to fault-tree analysis and network reliability problems are discussed     

Instrumentation for gathering data [DAQ systems]

The main characteristic of the intelligent distributed data acquisition system we describe in this article is that it supports intelligent functions and provides the desired accuracy of measurement. It is also reliable and adaptable, utilising two NN-based methods of sensor drift prediction, which allows it to increase its inter-testing interval, and provides accuracy of sensor data processing. The system is designed on a distributed intelligence scheme, which operates in real time for most industrial sensors.     

Semantic failure [of software]

The author offers the opinion that the adoption of the terminology of hardware reliability in the context of software was a terrible, probably unavoidable, and perhaps even necessary, mistake: terrible-because the words cannot have the same meanings in both contexts; and unavoidable-because today there are few systems whose reliability can be assessed without dealing with both     

Meter power [electricity metering]

The author discusses the problems caused by the privatisation of the UK electricity supply industry in the area of metering. The minimum requirements for changes in metering suggested by Offer (Office of Electricity Regulation) to improve demand side management, are discussed. The author then discusses communication techniques for improved metering. The author describes mains signalling and radio techniques for remote meter reading. The practical implications of using such technology and its benefits are discussed     

The power within [Internet]

The public Internet has revolutionised the world's communications. Now companies are rushing to build their own private intranets. The author explains some of the attractions that intranets provide: cross-platform functionality; a consistent view of information; an enabling technology path; ease of integration; ease of communication; relatively low-cost installation; and increased effectiveness of information     

Nonstop monitoring [power quality]

A power failure could spell disaster for a large financial institution. The author describes the role of fixed power quality monitoring systems in ensuring that the trading never has to stop. Consulting engineers and site facility managers are increasingly of the opinion that supply quality in a modern commercial building demands the installation of a fully integrated, fixed power quality monitoring system, operating 24 hours a day, 365 days a year. The PegaSys system, manufactured in Canada by Power Measurement Ltd of Victoria, British Columbia, and marketed in the UK by C-Matic Systems is an example of a modern, highly flexible, power monitoring system. A typical installation consists of one or more monitoring PCs connected to a network of fixed power quality instruments installed at all of the key supply points throughout a building. The PC's graphical interface depicts the electrical layout of the building, indicating the location of each monitoring instrument, together with the status of load levels or approaching alarm limits. Typically, a user will have one main screen where system condition can be viewed at a glance. More detailed information is available by navigating down through the hierarchy of screen layers. The objective of the system is to provide load trending for system planning together with pre-fault alarming, so that, as far as is humanly possible, power outages are avoided     

Tighter controls for busier systems [power systems]

A variety of new technologies are becoming available that will help utilities maintain power system reliability while handling the larger volume of transactions. For example, power electronic systems can provide unprecedented control over electricity flow on transmission networks, preventing or containing cascading disturbances. In addition, new sensor technology, faster communications between control centers, and advanced software tools can enable utilities to monitor system conditions in real time, letting them respond more quickly to disturbances and minimize their impact. Over the next decade, these technologies will facilitate increased power transfers through power delivery systems that are presently constrained, providing power at lower cost to a greater number of customers. It is a question of how to optimize power flow through an entire network by integrating multiple technologies and coordinating control over wide areas. Such integration and coordination will be necessary for deregulation to proceed smoothly toward its twin goals: reducing electricity costs to US consumers, while maintaining the high levels of reliability they have come to expect. The authors discuss the following technologies to help achieve these goals including: flexible AC transmission systems (FACTS), the next generation of FACTS controllers, hierarchical control of FACTS, on-line power systems analysis, control centre communications, and wide area measurement system     

Power struggle [power supplies for portable equipment]

Gadgets bristling with hardware and applications in smaller packages are forcing designers to consider new power sources. The leading candidate is a form of fuel cell based on methanol as fuel. A methanol based fuel cell produced by Toshiba to power a notebook computer is described in this article.     

Poison Java [data security]

In this paper, the author argues that antidotes to malicious code are required above and beyond Java's own antigens if the programming language is to be immunized against security breaches     

A phase reconstruction algorithm from bispectrum [seismicreflection data]

A computationally efficient procedure for the reconstruction of the impulse response of a (minimum- or nonminimum-phase) linear time-invariant system from its bispectrum is presented. This method is based on computing cepstrum of the impulse response sequence from the ω₁=ω₂ slice of the bispectrum. The algorithm can be implemented by using only the one-dimensional fast Fourier transform algorithm     

Efficient algorithm for glitch power reduction [CMOS logiccircuits]

An efficient algorithm is proposed for reducing glitch power dissipation in CMOS logic circuits. The proposed algorithm takes a path balancing approach that is achieved using gate sizing and buffer insertion methods. The gate sizing technique reduces not only glitches but also the effective circuit capacitance. After gate sizing, buffers are inserted into the remaining unbalanced paths which have not been subjected to gate sizing. ILP has been employed to determine the location of inserted buffers. The proposed algorithm has been tested on LGSynth91 benchmark circuits. Experimental results show that 61.5% of glitches are reduced on average     

Breaking the mould [power transmission]

The liberalisation of energy industries has become a major international concern. In this article, the author charts the experience of National Grid (NGC)-the world's first privately owned independent transmission company-in developing the complex roles of network manager and system controller within the radically changing electricity market in England and Wales     

Wheeling and dealing [power transmission]

Within a few years the transmission network will remain the last outpost of regulation within the electricity industry for England and Wales. The need for the long-term regulation of the transmission business raises important issues in the economic management of the electricity industry. In particular, what form of regulation will best help to promote the overall goal of economic efficiency within the industry? How should the services of the transmission business be priced? And how can the long-term security of the network be guaranteed? The author describes some of the challenges of combining a regulated transmission business with the quest for market-led economic efficiency