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We examine the ability of market forces, augmented by an “interference limit,” to improve the efficiency with which radio systems co-exist. In a bargaining game with incomplete information, an interference limit can increase the likelihood that two radio system operators can come to a mutually beneficial agreement about both the level of interference that should exist between two radio systems and the price the benefiting party should pay to establish that level of interference. It can achieve this by changing the bargaining environment in a way that makes it more likely that an efficiency enhancing agreement can occur. By imposing a cost upon the system operator from using low quality receivers, it can also lead to the manufacture of higher quality receivers. An interference limit’s ability to improve the efficiency of the co-existence of two radio systems depends, in part, on whether the regulator has “good” information regarding the level of benefit and harm that operators experience from a given level of interference. The better this information, the greater the likelihood than an interference limit will improve efficiency. When the regulator doesn’t have good information about the harm that an interfered-with operator experiences from a given interference limit level, an interference limit can lead to a less efficient level of co-existence of radio systems.

A real-life testing experiment of a proton exchange membrane fuel cell (PEMFC) and the basic characteristics of its voltage degradation are presented. A general package radio system (GPRS)-based remote monitoring system was used as the data acquisition method, and the non-linear regression method was used to estimate PEMFC's polarization curve within specific iso-interval periods. The voltage degradation rate was calculated using the differential method, and its average level was also analyzed. The experimental results indicated that the voltage degradation rate at a specific current density featured a bathtub-like curve, exhibiting 1) infant degradation, 2) steady degradation, 3) and accelerated degradation.

A unique resource providing continuous observations of the critical frequencies since 1935 and layer heights since 1952 has been used to determine the long-term trends above Tromso in Northern Norway (69°N, 19°E). These, and the recent results of Ulich et al. [Ulich, T., Cliverd, M.A., Rishbeth, H. Determining the long-term change in the ionosphere. EOS Trans. 84(52), 581–585, 2003] have then been used to illustrate the effects of layer height changes on radio system modelling and operation by reference to high frequency ground range and skip zone variations. The analysis ignores the effects of the variations in the underlying E-region and changes in the F2 layer critical frequencies. Consequently, the system impact is expected to be higher still. It is shown that a 16 km drop in h m F2 will introduce ground errors of ∼100 km with higher values under certain circumstances. The Tromso analysis indicate that these ground range errors will not occur until the year 2110, however, the results of Ulich et al. [EOS Trans. 84(52), 581–585, 2003] indicate that this condition occurred in the year 2000. This study demonstrates an urgent need to reach a consensus understanding of long-term ionospheric trends. A reassessment of the CCIR and URSI worldwide maps of ionospheric characteristics is likely necessary.

The Army is facing a number of challenges now and in the future. One of the major challenges is in the power sources arena. As the Army continues to move toward digitizing the battlefield, the need for portable power is increasingly becoming a technological hurdle that must be overcome in order for a soldier to exercise his electronics capabilities without being overburdened by the power sources size, weight and operating/logistical costs. Advanced electronic devices are becoming a critical piece of the soldier's personal battlefield equipment. A soldier with the latest version of the Single-Channel Ground and Airborne Radio System (SINCGARS) is one of the most dangerous weapon systems on the modern battlefield. The ability to accurately navigate and communicate multiplies the soldier's advantage over a less electronic capable enemy. Keeping his personal electronics operational is crucial to giving the soldier the capability to complete his mission successfully. Inherent in keeping the electronic equipment operating is keeping it supplied with batteries. Due to the increased emphasis placed on the modern soldiers electronic equipment, the importance of the portage of the power sources needed to keep this equipment operational has also increased. Recent efforts have focused on hybrid power sources that may enhance discussed capabilities by taking advantage of both high energy sources and high power systems for intermittent power application. This development could lead to a power source with enough energy to meet the Army's preference for a 72-h mission life before the need for resupply.

a new optical-electronic measuring method of mutual orientation between two spatial vehicles is represented, and a corresponding system is devised in this paper. It has advantages of a high measuring precision and rapid calculating speed, compared with radio system, and can be used to help precisely automatically dock two space vehicles. Effective distance is about several tens of meters

This paper will discuss the use of a point-to-multipoint subscriber radio system in both a line/loop extension and intelligent network node configuration to support basic rate ISDN subscribers' terminal equipment. Considerations involved in each type of implementation are included in the discussion as well as the concept of an open structure which will enable the line/loop configuration to be used as a basis for an intelligent node implementation.

This report details the first in-depth evaluation of a medical emergency radio system. The methodology emphasizes evaluation of problems in human/machine interface and the use to which radio information is put by the hospitals. The radio equipment was reliable. A check-out procedure could reduce needless calls for repair. The results of a test of knowledge of the system were poor, but improved with frequency of use. Hospital personnel felt the use of the system improved patient care to a greater degree than did ambulance company personnel. Twenty-five percent of the ambulance personnel felt the hospitals were seldom prepared to receive patients while hospital personnel felt they were prepared 95.5% of the time. The system could handle twice the volume of calls without significantly increasing the chances for interference. The system was generally effective but changes in organization, training and human factors could enhance the usefulness of the system within the technological boundaries imposed by the radio equipment.

This paper describes the control system for the Usutu River Government Water Scheme which supplies raw water to Camden (1600 MW), Kriel (3000 MW) and Matla (3600 MW) power stations. The project was designed by Escom on behalf of the Department of Water Affairs of the South African Government. The heart of the system is a dual computer installation operating in real time mode which communicates with the outstations via a duplex fixed link radio system. In addition to the usual display and manual control facility, the system can be used on auto control so that it regulates itself to within pre-set values without any operator intervention. Safety features and interlocks are also built into the software to prevent operation or to shutdown items of plant or the entire system, should the normal operating conditions not prevail.

Evidence has been found for correlation between optical and radio emission from extensive air showers at large zenith angles, using a Cerenkov optical detector and wide-band radio system.