A Review of: “Bibliography of Geologic Studies Using Imaging Radar.” Compiled by M. LEONARD BRYAN. (JPL Publ. 79-53, 1979.) [Pp. 121.] Available from NASA/JPL,California Institute of Technology,Pasadena, California,U.S.A.

In high mountainous areas, such as the Himalayan Range where snow melt run-off contributes substantially to streamflow, information on snow depth and snow areal extent is vital for the estimation of streamflow and for water resources management. Microwave radiationpenetrates through clouds and snowpacks and is thus considered an important tool for providing water equivalent information on snow fields. The scanning multichannel microwave radiometer (SMMR) on board the NIMBUS-7 satellite acquired passive microwave data for 9 years (1978-1987). These SMMR data are used to test a snow algorithm that is applicable for high elevation areas (>3500m) in the Himalayan Range. The study demonstrates promising results, suggesting the application of SMMR data to derive snow-depth and snow-extent information for the Himalayan region. The generated snow maps can be used for various hydrological applications. The limited availability of field data and its comparison with the SMMR data (which are areal in nature), are major limitations in achieving close correlations between two observations. This is the first application of SMMR data for the determination of snow parameters in the Indian Himalayas. Thus, such an application sets a pace for further research and application of passive microwave data in the most rugged terrains of the world.     

A review of: “Computers,Work and Health”. By TREVOR A. WILLIAMS,Taylor & Francis, 4 John St,London WC1N 2ET (1988), pp. x + 142, £25·00. ISBN 0-85066-453-5

The effects of cabin noise on subjective comfort assessments were systematically investigated in order to reveal optimisation potentials for an improved passenger noise acceptance. Two aircraft simulation studies were conducted. An acoustic laboratory test facility provided with loudspeaker systems for realistic sound presentations and an aircraft cabin simulator (Dornier Do 728) with a high degree of ecological validity were used. Subjects were exposed to nine different noise patterns (three noise levels ranging from 66 to 78 dB(A) combined with three different frequency spectra). Regression analysis demonstrated a significant increase of passengers' acceptance with lower noise levels and significant effects of different frequency spectra determined by seat position in the aircraft cabin (front, middle, rear). Acoustic cabin design should therefore consider measures beyond noise level reduction altering noise characteristics to improve passengers' comfort and well-being in the aircraft cabin.

Practitioner Summary: To improve passenger comfort in the aircraft with respect to cabin noise, passengers' reactions to specific noise conditions were systematically investigated. Two laboratory studies showed significant dose-response relationships between sound pressure level and subjective comfort ratings which differed due to the noise at specific seat positions in the aircraft.     

Review of: “Glaciers-Ocean-Atmosphere Interactions”. Edited by V. M. KOTLYAKOV,A. USHAKOV and A. GLAZOVSKY,Proceedings of the International Symposium,St Petersburg, 24-29 September 1990 (Wallingford,UK: IAHS Press, 1991.) [Pp. 549.] Price US$60.

Data gathered during the NASA sponsored Multisensor Aircraft Campaign Hydrology (MACHYDRO) experiment in central Pennsylvania (U.S.A.) in July, 1990 have been analysed to study the combined use of active and passive microwave sensors for estimating soil moisture from vegetated areas. These data sets were obtained during an eleven-day period with NASA's Airborne Synthetic Aperture Radar (AIRSAR), and Push-Broom Microwave Radiometer (PBMR) over an instrumented watershed, which included agricultural fields with a number of different crop covers. Simultaneous ground truth measurements were also made in order to characterize the state of vegetation and soil moisture under a variety of meteorological conditions. Various multi-sensor techniques are currently under investigation to improve the accuracy of remote sensing estimates of the soil moisture in the presence of vegetation and surface roughness conditions using these data sets. One such algorithm involving combination of active and passive microwave sensors is presented here, and is applied to representative corn fields in the Mahantango watershed that was the focus of study during the MACHYDRO experiment. In this algorithm, a simple emission model is inverted to obtain Fresnel reflectivity in terms of ground and vegetation parameters. Since Fresnel reflectivity depends on soil dielectric constant, soil moisture is determined from reflectivity using dielectric-soil moisture relations. The algorithm requires brightness temperature, vegetation and ground parameters as the input parameters. The former is measured by a passive microwave technique and the later two are estimated by using active microwave techniques. The soil moisture estimates obtained by this combined use of active and passive microwave remote sensing techniques, show an excellent agreement with the in situ soil moisture measurements made during the MACHYDRO experiment.     

A review of: “Man in the Antarctic The Scientific Work of the International Biomedical Expedition to the Antarctic (IBEA)”, edited by J. RIVOLIER,R. GOLDSMITH,D. J. LUGG and A. J. W. TAYLOR,Taylor & Francis, 4 John Street,London WC1N 2ET (1988), pp. 222, £26·00, ISBN 0-85066-280-X

This study aimed to examine the effects of passive and non-computer work time on the estimation of computer use times by electronic activity monitoring. A total of 20 subjects with computers were monitored for 3 h. Average relative error for total computer use time estimation was about 4%, given that non-computer work time was 20% of the 3-h monitored period. No significant impact of passive computer use time was found in this study. Non-computer work time of 40% or less is suggested as criteria for the application of electronic activity monitoring to ensure reliability in the physical work loading assessment.

Statement of Relevance: This research studied the criteria of non-computer work time for the appropriate use of electronic activity monitoring to ensure reliability in the assessment of physical work loading. It is suggested that it should be set to 40% or less of the 3-h monitoring period.     

A Review of:“Fundamentals of Psychology”. By FRANK A. GELDARD. ( New York,John Wiley and Sons. ) [Pp.437.] 57s.

Abstract

Industrial Design is a discipline which, despite an early pre-occupation with styling and making technology saleable, is now centrally concerned with user needs. This is reflected in Coventry's unique degree course in the Industrial Design/Transport Department at Lanchester Polytechnic. The course contains a significant commitment to Human Factors and this is evident in the range of design projects which are undertaken either by students or as sponsored research. The emphasis in these projects is on practical designs which meet user requirements.

This paper describes the following typical course projects:

1. The competition winning design for a dinghy which can be used as an emergency life-raft.

2. An adaptation of a standard front-wheel-drive car with a transverse slide seat to allow easy access for a wheel chair user.

3. The design for a bus seat which can be used either as a conventional seat or as a standee ‘lean’ seat.

4. Design of a vehicle for use by spina bifida children.

5. Design for a pedal driven power unit for transport and machine uses in Developing Countries.

6. The design of adult tricycles for the transport of mothers plus children under 5 yr.

It is concluded that greater collaboration between industrial designers and ergonomists would be possible if the latter published their data in a more accessible form, and that designers must place greater emphasis on the product evaluation aspect of their work.     

A review of: “Human Motor Actions: Bernstein Reassessed.” Edited by H. T. A. WHITING. (Oxford: North-Holland, 1984.) [Pp. xxxv + 633.] ISBN 0-444-86813-5.

The physical work performance of eight fit fire fighters wearing fire brigade uniforms and wearing breathing apparatus was assessed. They were tested in a climatic chamber set at temperatures of 15 and 45°C respectively. The test was performed with and without fire fighting equipment. The subjects walked on a treadmill at a speed of 3.5km/h, which produce a workload equivalent of 20% of the subjects' maximal oxygen uptake without equipment, and 30% with equipment. The test lasted for 60 min. Heart rate, oxygen uptake, skin and deep body temperatures were measured during the test. The subjects estimated perceived physical exertion and perceived temperature. Wearing fire fighting equipment increased the oxygen uptake by 0.4 1min^-1. Heart rate at the end of the experiments reached near-maximum levels when the temperature was 45°C with equipment, and deep body temperature increased to an average of 38.7°C. The subjects' ratings of perceived exertion were highly correlated to heart rate. The loading induced by heat and protective equipment reduced the ability to perform strenuous work. The combination of thick clothing and heavy breathing apparatus was found to have a significant limiting effect on the endurance of fire fighters.     

A review of: “Posture. Sitting,standing, chair design and exercise.” By D. ZACHARKOW. (Springfield,IL: Charles C. Thomas, 1988.) [Pp. xxi + 433.] US$49·75. ISBN 0-398-05418-5.

Drivers experiencing rush hour congestion were interviewed using cellular telephones to study stress and coping responses. Measures were taken of each driver's predisposition to stress (trait stress) as well as their reactions to the experience of either low or high traffic congestion (state stress). Two interviews were conducted during the trip when drivers experienced both low and high congestion conditions. Although state stress was greatest for all drivers experiencing the high congestion condition, a trait X situation interaction was obtained, indicating that stress levels were highest for high trait stress drivers experiencing the congested roadway. In terms of trait coping behaviours, participants indicated a preference for direct over indirect behaviours. A greater variety of direct and indirect behaviours were reported in high congestion. Reports of aggressive behaviours showed the greatest increase from low to high congestion. Comments on the use of cellular telephones in methodology are offered.     

A review of: “Human Judgments and Optimality.” By M. W. SHELLY,II, and G. L. BRYAN (Editors). (John Wiley, 1964.)

Abstract

In order to evaluate the efficiency of various commercial chemical fabric softeners, a technique of obtaining subjective assessment known as ‘magnitude estimation’ was used to estimate the fabric softness. Particular emphasis was given to subjective scaling and limits of human perception. Comparison between softness and compression ( a physical measure) was demonstrated     

CMOS Design of Ternary Arithmetic Devices Wu Xunwei Dept.of Electronic Engineering,Hangzhou University,Hangzhou 310028F.P rosser Dept.of Computer Science,Indiana University,U.S.A.

This paper presents CMOS circuit designs of a ternary adder and a ternary multiplier,formulated usingtransmission function theory.Binary carry signals appearing in these designs allow conventional look-aheadcarry techniques to be used.Compared with previous similar designs,the circuits proposed in this paperhave advantages such as low dissipation,low output impedance,and simplicity of construction.