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A qualitatively different graduate level curriculum for teaching electric power systems is needed. The motivation for such a new curriculum is outlined, and a specific program, now being implemented at Carnegie Mellon University, is described. The new curriculum: 1) provides students with a multidisciplinary introduction to the changing problems of the industry; 2) stresses the need for teaching systematic approaches to formulating power system problems; and 3) integrates teaching of the fundamentals for power systems with the fundamentals for other network industries. The program, referred to as the MS in Electric Power Systems (MSEPS) Program, is being developed as a special power-focused track within Carnegie Mellon's existing multidisciplinary Information Networking Institute (INI).

Structured interviews using `expert elicitation` methods drawn from decision analysis were conducted with 16 leading U.S. climate scientists. We obtained quantitative, probabilistic judgments about a number of key climate variables and about the nature of the climate system. We also obtained judgments about the relative contributions of various factors to the uncertainty in climate sensitivity. We found strong support for the importance of convection/water vapor feedback and of cloud optical properties. A variety of questions were posed to elicit judgments about future research needs and the possible sources and magnitude of future surprises. The results reveal a rich diversity of expert opinion and, aside from climate sensitivity, a greater degree of disagreement than is often conveyed in scientific consensus documents. Research can make valuable contributions, but we interpret our results to mean that overall uncertainty about the geophysics of climate change is not likely to be reduced dramatically in the next few decades. 22 refs., 5 figs., 2 tabs.

Stabilizing atmospheric carbon dioxide levels at acceptable levels will require a dramatic de-carbonization of the electric generation sector in the U.S. One increasingly discussed way to meet this policy goal is to put an explicit price on carbon emissions, either through a tax or a trading scheme. Increasing demand response has also been discussed as a way to reduce carbon emissions in the U.S. electricity industry. We examine the short-run effectiveness of a policy combining demand response with a carbon tax. Using plant-level operational data, we construct short-run cost curves for three U.S. regional electric systems, and examine the impacts on prices and carbon emissions. In the short run, a carbon tax in the range of $30 - $40 and a price elasticity of demand in the range of -0.1 to -0.2 could reduce carbon emissions in coal-intensive regions by 10% to 25%. With this same set of carbon prices, achieving a 50% reduction in emissions would require a price elasticity of demand in the range of -0.25 to -0.4. Percentage reductions of this magnitude in less carbon-intensive systems are unlikely, even with highly elastic demand and high carbon prices.

We describe a case of septic arthritis in a child with no apparent predisposing conditions. Salmonella virchow was isolated from her knee and faeces, both isolates being identical except for the latter's resistance to ampicillin. Evidence is presented for the acquisition of ampicillin resistance in vivo, including the demonstration of the R plasmid and its ready transferability to Escherichia coli. The recent literature on the subject is reviewed and the role of group CI salmonellae in invasive disease is examined.

Air sampling and surveillance cultures for fungi were performed in a Scottish general haematology ward over a five-month period in 1997. The mean total fungal count from the air sampling appeared to be correlated with the number of patients colonized by Aspergillus. The most commonly isolated species were Aspergillus versicolor, A. fumigatus and A. niger. Rooms with portable air filtration units had significantly lower total fungal counts than the others. Swabs were taken from 70 patients (mean age 62 years); 114 of the 563 cultures (20.2%) were positive. The most commonly isolated species were A. fumigatus, Candida albicans, C. glabrata and C. parapsilosis. Samples taken from the tongue and perineum showed colonization more often than those taken from the nostrils. Almost half the patients (48.6%) were colonized on, or within seven days of, admission; 11.4% became colonized whilst on the unit. One patient developed fatal aspergillosis. We conclude that colonization or high air-borne spore concentrations are not necessarily predictive of fungal infection but may prompt early treatment or more aggressive prophylaxis of potentially fatal invasive infections.

Two cases are described, one of Haemophilus influenzae urinary infection in a female with no past history of urinary tract infection (UTI) and the other of Haemophilus parainfluenzae infection in a male with a renal calculus. Haemophilus spp. are rare urinary pathogens and these cases are even more unusual because H. influenzae UTI has almost always previously been found in either children or adult males, while H. parainfluenzae UTI has only been reported once before.

An analysis technique is presented for dealing with uncertainties in quantitative environmental risk analysis. Assessments of the health effects from a 1 GW sulfur-scrubbed coal-fired power plant in the upper Ohio Valley are presented. The annual average concentration of sulfate aerosol was chosen as the air pollutant of interest. The work performed was divided into three broad tasks: developing mass balance models for multiday transport, developing models to estimate population exposures, and developing models to estimate rates of mortality arising from the exposures. Leading atmospheric science and health effects experts were chosen to participate in the study.

We undertook a retrospective, longitudinal survey to monitor the changing incidence, phage types and patterns of antibiotic resistance of methicillin-resistant Staphylococcus aureus (MRSA) in St Laurence's Hospital (SLH), Dublin over the last 10 years. Following a peak in 1979, the incidence of MRSA has gradually decreased to around 17% of S. aureus isolates in 1986, almost identical to its incidence 10 years before. However, the spectrum of antibiotic resistance among these organisms remains broad and this seems to be at least partially related to antibiotic usage. Many strains could not be phage typed and others were typable only by the additional phage 90. This has severely limited the usefulness of phage typing in the tracing of sources of outbreaks. Thus, there is a need for a more specific method of typing as well as a rational antibiotic policy, to successfully monitor and curtail the hospital spread of MRSA.

Available experimental evidence on possible human health effects from exposure to high voltage ac transmission line electromagnetic fields is contradictory and inconclusive. Yet, in several states, growing public concern is regulatory action. A number of alternative technologies are available to control human exposure to these fields. This paper looks briefly at the available evidence on health effects, estimates the costs of possible control technologies, and then performs an analysis to bound the region of appropriate control strategies for electric field exposures for representative 500 and 765-kV ac transmission lines. Results are presented parametrically in the key variables. Both the value and the potential societal costs of the analytical approach we take are discussed.

Four methods of investigating the thermal plasma density near the plasmapause are intercompared for the period of July 1 to 15, 1972. These methods are whistlers, the double floating probe on Explorer 45, three IMP I plasma wave signatures, and observations made aboard both Prognoz 1 and Prognoz 2. Explorer 45 data have provided new information on the plasmapause bulge which, during this period, occurs at 16 L.T. This displacement from the accepted time of 18 L.T. or even later is substantiated by the Russian satellites. All methods give the result that the plasmapause is found at an electron number density somewhere between 20 and 120 per cu cm or, alternatively, at 60 per cu cm, to within a factor of 2.

This paper provides a review of the subject of electric power load management. In Section I, we briefly introduce the topic and then provide a summary of the current operating characteristics of electric energy production and delivery (EEPD) systems. Section II places load management in the context of the broader set of energy management strategies available to EEPD systems. The organization and rationale of the paper is then explained. In Section III, we review the set of communication/control technologies available or under development for use in the implementation of load management in EEPD systems. We provide an assessment of the relative attractiveness of alternative technologies, a brief summary description of a major field demonstration being jointly funded by EPRI and DOE, and two examples which illustrate the state of the art in modern two-way systems. In Section IV, we review the conventional approach to U.S. electric rate design, describe the current national Electric Utility Rate Design Study, review some important basic ideas of microeconomics, explore the subject of price elasticity of demand, examine the basic ideas underlying marginal cost pricing, discuss some of the practical difficulties of implementing time dependent rates, briefly examine some foreign rate design experience, and conclude by summarizing a number of U.S. rate design experiments sponsored by NSF and by FEA (now DOE). Section V is devoted to an examination of the problems of finding manageable loads in the residential, commercial, industrial, and transportation sectors. Particular attention is given to the development of thermal storage systems for water heating, space heating, and space cooling. Section VI is devoted to summarizing a number of studies which have attempted to assess the short- and long-term economic impacts of load management. The state of the field is such that few definitive cost/benefit statements can be made at this time. A number of potential social impacts are discussed and some broad regulatory policy guidelines are suggested. Finally, in Section VII, we highlight conclusions reached in the five preceeding sections, and identify a number of research and policy needs.

We conducted a prospective trial to identify organisms colonizing the urethra and prostate and their role in the aetiology of infection after prostatectomy. Twenty-five patients were studied of whom six developed postoperative infection. The causative organisms were previously recovered from the urethra but not the prostate. There was a high rate of urethral colonization by streptococci (14/25) and a low incidence of prostatic colonization. We describe a novel method of sampling the prostate.

A methodology is discussed for quantitatively computing the social costs, or external diseconomies, which result from the production of electric power in conventional coal-fired steam electric plants. With the available data, and our present level of understanding, it is possible to obtain preliminary numbers which place the social cost for the technology of the mid and late 1960's at ≥ 11.5 ±2 mills/kWh, somewhat more than the price of bulk power at the plant bus bar. In applying controls to limit the social costs, control costs are incurred. If the optimum level of control is taken as that level at which the sum of the social costs and the control costs is minimum, then we estimate the total social and control costs with optimum control as ≥4.5 ± 1.5 mills/kWh and the costs of controlling to that level as ≥3 ± 1 mills/kWh. These numbers will probably be reduced, and the optimum levels for control increased, as new technologies are developed. The paper is limited to a straightforward development of social costs. No attempt is made to develop policy implications or to draw broad conclusions on the basis of the costs which are derived.

Some interesting curves result when whistler data are averaged over a long period of time to smooth out random short-term variations in whistler generation and propagation. Local season is such a strong factor in determining the shape of the diurnal curves of observed whistler activity that even in the case of the north-south "Whistlers-East" chain of audio-frequency receiving stations, diurnal curves of the northern- and southern-hemisphere stations tend to be similar not during the same period of the year but during the same local season at the point of observation. A basic form of the diurnal curves appears to be one which is symmetrical about local midnight with a deep minimum at local noon and relatively high nighttime activity showing maxima at about 2000, 2400 and 0400 hours local time. Depending on local season and location of the station, one or more of these peaks may be absent or enhanced. It is concluded that the shape of the diurnal curves is determined largely by the conditions of whistler propagation rather than of generation. The curves presented should therefore be useful in predicting the behavior of man-made signals propagating in the "whistler mode" through the ionosphere and the magnetosphere of the earth. Some difficulties are pointed out with the prevalent idea that the marked depression in the occurrence of whistler-mode signals in the daytime is primarily the result of absorption of these waves in passing through the D layer. On the other hand, caution is advised against neglecting ionospheric factors, other than D-region absorption, in deference to the role of field-aligned ducts of enhanced ionization in the magnetosphere. Finally, some results are presented which show that, in addition to a latitude variation of the dependence of whistler rate upon the K p index of geomagnetic disturbance, there is, especially at the lower latitude stations, a seasonal variation of these curves as well. Of particular interest also is the observation that, at the higher latitude stations where the maximum whistler rate obtains at low values of K p , the rate decreases almost linearly with greater values of K p .

The general case of elliptic polarization produced by three mutually perpendicular sinusoidal electromagnetic field components at a point in space is treated. The elliptic locus is specified in terms of the sinusoidal components and conversely the components are specified when the locus is known. The simpler two-component case is solved first.

The development of a pulse generator and a modulator which will produce pulses of 10-7second duration and 3,000-volt amplitude at a 1-Mc recurrence frequency is described. The modulator is developed for the special case of a nonlinear load impedance consisting of 125 μμf capacitance for the leading half of the pulse and a spark discharge for the trailing half. The high recurrence frequency gives rise to problems not generally encountered in the design of pulse circuits. Other applications, such as the second modulation of a high-recurrence-frequency pulsed carrier with voice frequencies, suggest themselves. A new pulse-generating circuit, capable of producing positive pulses whose duration is one-tenth the period of the 1-Mc input sine wave, is developed. This pulse generator can be operated at moderate power levels sufficient to drive the modulator.

Continuous and triggered audio frequency noise bands associated with ionospheric lower hybrid resonance frequency observed on OGO 2

Synoptic observations made on magnetic recording tape at Huancayo, Peru, at the magnetic dip equator, during the International Geophysical Year 1957–1958, were aurally reviewed at that time and no whistlers, hiss, or other emissions were heard. In view of the more recent observation of whistlers at geomagnetic latitudes as low as 12°, and in conjunction with a study of equatorial hiss observed in the topside ionosphere, these recordings have recently been reassessed by reducing them with modern real-time, digital spectrographic equipment. Although the observations were found to be of high quality, and to show the classical features of ground-wave and sky-wave propagation of sferics and VLF transmissions, again no evidence whatsoever of whistlers, hiss, or other emissions is found. Thus it is concluded that the whistlers observed at very low latitudes do not propagate subionospherically to the equator and it is confirmed that “hybrid” whistlers must be due to subionospheric propagation across the equator of the causative sferic rather than of the short whistler.

Knowledge of the relationship between ambient air pollution levels measured at fixed monitoring stations and the actual exposure of the population is very limited. Indeed, there is rapidly growing evidence that fixed-station monitors do not provide adequate data for population exposure. This report examines available data for carbon monoxide (CO) and sulfur dioxide (SO/sub 2/) and presents a new analysis. Actual population exposure to CO appears to be consistently higher than expected from fixed-station data, while limited evidence suggests that exposures to SO/sub 2/ are lower. A reported general relationship between indoor and outdoor levels of SO/sub 2/ is not supported by the data. If air pollution represents a threat to public health, then more attention must be given to total population exposure to pollutants. A selective use of individual air pollution monitors that can be worn or carried appears to be required at some stage by any experimental design seeking to uncover the relation between air pollution exposure and health effects. Additionally, potential uses of individual monitoring in air pollution regulation are explored. Current status and research needs for individual air pollution monitors are examined and a first-order evaluation is given of the promise held by the candidate instrumentationmore » technologies. A national program of support for the development of individual air pollution monitors is recommended.« less

The deliberations and conclusions of a workshop on national research needs in individual air pollution monitors for ambient air are reported. The weakest link in air pollution health effects studies is knowledge of individual exposure. Monitors which can be easily carried or worn are necessary to the design or performance of definitive studies of the health effects of air pollution. The report includes discussion of how individual monitors would be used if they were available, an outline of their desired operating characteristics, and a description and first-order evaluation of the instrumentation technologies which might form the basis for such devices. A five year national R and D investment of 7.5 to 8 million dollars is recommended.

The history, purpose, and functioning of URSI, and the relationship of the United States National Committee of URSI to the IEEE, are described. A few examples demonstrating the interest of the Union in the field of this special issue of the PROCEEDINGS are given.