Review of: “Machine Intelligence 7”. Edited by Bernard Meltzeb and Donald Michie.(Edinburgh University Press, 1972.) [Pp. xiv+485.] £12.00.

To better assess the energy expenditure and exertion of firefighters during simulated firefighting activities, a commercial firefighter self-contained breathing apparatus (SCBA) facepiece was modified to interface with a portable metabolic monitoring device (Cosmed K4b²) while still functioning as a positive pressure SCBA air supply. To validate the device, standard National Fire Protection Association 1981 SCBA function tests were conducted and 14 subjects performed variable-workload assessments using all combinations of two test devices (Cosmed K4b² and metabolic cart) and two masks (modified SCBA facepiece and stock manufacturer-supplied breath collection). Metabolic data collected with the Cosmed K4b² via the modified facepiece were found to be accurate when compared to a ParvoMedics Truemax 2400 metabolic cart (average per cent difference: 4.6%). This modified facepiece design is suitable for use in metabolic studies requiring the utilisation of an SCBA system. Furthermore, the well-established overestimation of oxygen consumption from the Cosmed K4b² system was replicated.     

Review of: “ Integrative Approaches in Remote Sensing.” Edited by N. LONGDON (Noordwijk,The Netherlands: ESTEC,ESA SP-214. Proceedings of an EARSeL/ESA symposium, 8-11 April 1984.) [Pp. 375.] Price Ff 170.

Three AVHRR-LAC data sets acquired in September 1990 and January 1991 were used to map the forest resources of Madagascar. The island was partitioned into four strata to include: (1) the western hardwoods, (2) the central grasslands, (3) the eastern rainforest, and (4) spiny forest. Each stratum was classified separately using AVHRR-LAC data in conjunction with 1984-1988 Landsat-MSS photoproducts. The results of AVHRR classification indicate that approximately 11 per cent of the island is covered by forest. Approximately 1 per cent of the island was obscured by clouds and could not be enumerated. Estimates of forest area, by stratum, follow: western hardwoods, 6697 km²; central grasslands, 2830km²; eastern rainforest 34167km²; and spiny forest, 17 224 km². The total forest area on the 587041km² island is estimated to be 60918km². The AVHRR forest map was compared to a mid 1970s land cover map which was developed using Landsat-MSS photoproducts. The average class agreement between the mid 1970s ground reference map and the 1990 AVHRR-LAC map was 78-2 per cent, the overall accuracy was 81-1 per cent. Areas identified as forest on the ground reference map on the 1990 AVHRR map agreed only 62 per cent of the time, however, that figure confounds AVHRR misclassifi-cation error with actual forest loss over the decade. Much of the per-pixel disagreement between the ground reference and AVHRR maps involved areas identified as forest in the 1970s and as nonforest in 1990. These results demonstrate that one kilometre spatial resolution satellite data may be used to provide a reconnaissance level survey of the forest resources of a region or subcontinent when used in conjunction with fine resolution data.     

Review of: “Management by Motivation”By Saul W. Gellerman. (American Management Association,’1968.) [Pp. 286.] $0.

This paper examines the effects of different types of complexity facing novice designers in constraint satisfaction tasks. The nature of the complexity in a design task was varied by manipulating different aspects of the extrinsic constraints, which refer to restrictions concerning how design components can be assembled. We investigated the effect of the number of constraints (Study 1) and the number of different types of constraint (Study 2) in a simulated office design task. Results indicated that tackling a design task with a greater number of constraints, or more types of constraint, resulted in decrements in performance. Study 3 examined the effect of reasoning about constraints that involved a fixed location in the office layout and those that did not. It was found that having a higher proportion of constraints that referenced a fixed location led to better design performance. The theoretical and practical aspects of these results are discussed.

Practitioner summary: This paper identifies sources of constraint complexity facing the novice designer in an office design task. Three features of constraints proved problematic: the number of constraints, the number of types of constraint and whether the constraint involved a specific location. Training and decision support solutions are discussed.     

Review of:“Design of Man-Computer Dialogues” By James Martin. (Englewood Cliffs,N.J.: Prentice-Hall, 1973.) [Pp. xiii+559.] £8.30.

Abstract

An electromyographical field study was performed in the operating theatre on four surgeons during 15 urological operations. In the course of the operations two endoscopic techniques were applied alternately: (1) direct endoscopy, and (2) monitor endoscopy. During direct endoscopy the surgeon looks into the urethra and the bladder via an endoscope. In monitor endoscopy, by contrast, the operating area is observed via a video system consisting of a camera mounted on top of the endoscope and a monitor. During the operations surface electro-myograms were derived from both trapezius muscles, the right deltoideus muscle and the left erector spinae muscle. An activity code describing the surgeons’ activity was additionally recorded. Analysis of the activity recording reveals that the monitor endoscopic method is preferred in the first third of the operations, whereas preference is given to the direct method in the last third. The electromyographical measurements indicate that during monitor endoscopy the myo-electrical activity of both trapezius muscles and of the right deltoideus muscle is significantly reduced in comparison with the activity for the direct endoscopic technique. A significant influence of the surgical technique on the myoelectrical activity could not be established for the erector spinae muscle. The electromyographical findings reveal that the activity of the shoulder musculature required for the maintenance of the posture and the performance of the operation is significantly lower in monitor endoscopy than in direct endoscopy. Consequently, a clear reduction in muscular strain can be achieved during the performance of endoscopic operations in urology if a video system is employed.     

A review of: “ Advances in Digital Image Processing: Theory,Application, Implementation ”. Edited by P. STUCKI. (New York,London: Plenum Press, 1979.) [Pp. 332.] Price $39·50.

Abstract

Radiometric balancing is a form of radiometric correction that can be applied to radar imagery. However, its application can be based on untenable assumptions about the characteristics of the scene and so can be unreliable. The method of radiometrically balancing an image and the requirements of the technique are outlined along with an example of where its use would be inappropriate. A recommendation is made against policies of pre-dissemination radiometric balancing and it is suggested that users should evaluate the use of other techniques which may be more suitable for their imagery.     

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: “System Identification—Parameter and State Estimation.” By PIETER EYKHOFF. (Bristol : John Wiley & Sons, 1974.) [Pp. 555.] Price £12.50.

This article extends the concept of input–output finite time stability (IO–FTS) to a class of hybrid systems, namely impulsive dynamical linear systems, which are systems that exhibit jumps in the state trajectory. Sufficient conditions are given for the analysis of IO–FTS and for the design of both static output and state feedback controllers, guaranteeing IO–FTS of the closed loop system. In the general case the presented results require to solve feasibility problems involving either linear matrix inequalities or bilinear matrix inequalities, which can be solved numerically in an efficient way by using off-the-shelf optimisation tools, as illustrated by the proposed examples.     

A Review of: “Exploration of the Solar System by Infrared Remote Sensing”. By R. A. HANEL,B. J. CONRATH,D. E. JENNINGS and R. E. SAMUELSON. (Cambridge: Cambridge University Press, 1992.) [Pp. 458.] Price £75.00.

Crop classification is a key issue for agricultural monitoring using remote-sensing techniques. Synthetic aperture radar (SAR) data are attractive for crop classification because of their all-weather, all-day imaging capability. The objective of this study is to investigate the capability of SAR data for crop classification in the North China Plain. Multi-temporal Envisat advanced synthetic aperture radar (ASAR) and TerraSAR data were acquired. A support vector machine (SVM) classifier was selected for the classification using different combinations of these SAR data and texture features. The results indicated that multi-configuration SAR data achieved satisfactory classification accuracy (best overall accuracy of 91.83%) in the North China Plain. ASAR performed slightly better than TerraSAR data acquired in the same time span for crop classification, while the combination of two frequencies of SAR data (C- and X-band) was better than the multi-temporal C-band data. Two temporal ASAR data acquired in late jointing and flowering periods achieved sufficient classification accuracy, and adding data to the early jointing period had little effect on improving classification accuracy. In addition, texture features of SAR data were also useful for improving classification accuracy. SAR data have considerable potential for agricultural monitoring and can become a suitable complementary data source to optical data.     

A Review of: “The Psychology of Thinking”. By NEIL BOLTON. (London: Methuen; New York: Barnes and Noble, 1972.) [Pp. ix+291.] £3.20.

We are in the midst of a major shift in the way computers are designed and used. The architectures, both of computer systems and of the organizations which use them, are changing from hierarchies (‘tiers’) to networks (‘peers’). This gives us, as individuals and as a profession, a challenging opportunity to enlarge our ‘systems approach’ in order to help solve the difficulties which will inevitably arise from such a major shift.     

A review of: “Health Hazards of the Human Environment.” (Geneva: World Health Organization, 1972.) | Pp. 387.] £4 40

This study investigated coordination of the grip force on and force applied with a hand tool using a precision pinch grip. A simulated hand tool was developed to measure grip force exerted on the tool as a function of the force transmitted from the tool to an external object in a dynamic force matching paradigm. Grip force coordination measures reflected subjects' abilities to modulate grip force in parallel with the tool application force and their abilities to minimize excessive grip force. These measures were calculated for seven subjects with a diagnosis of carpal tunnel syndrome (CTS) and seven age- and gender-matched controls. The absolute magnitude of excessive grip force (safety margin) was unreliable because of the high intrasubject variability in coefficient of friction measurements. Linear regression equations predicting coefficient of friction from pinch force magnitude had low r ² coefficients of determination and were generally not statistically significant (p &;gt; 0.05). Relative comparisons of grip force control showed that individuals with CTS exhibited a statistically significant (p &;lt; 0.05) increase in ratio of grip force to application force (54% higher than controls) and a significant (p &;lt; 0.05) decrease in modulation of pinch force with application force (12% lower than controls). These results suggest that individuals with CTS lose some ability to coordinate efficiently grip force on hand tools and exert higher grip forces on tools, at equivalent application forces, than controls. This is believed to be a result of tactile sensibility deficits associated with CTS. As a result, workers with CTS may be at increased risk of accelerating the progression of their musculoskeletal disorder.     

A Review of:“Safety in Manual Materials Handling.” By COLIN G. DRURY. (Cincinnati: US Dept. of Health,Education & Welfare, 1978.) [Pp. viii+ 209.]

The extension force against resistance was recorded in 23 postures for 12 subjects to find explanations for the decrease in back strength in asymmetric postures. A reduction in muscle force in asymmetric postures was found up to 40%, but was strongly dependent on the plane in which asymmetry occurred, and on the posture to which it referred. A quantitative relationship between the forces exerted in different asymmetric postures is discussed, as a basis for formulating universal ergonomic guidelines for optimal working postures. The reduction in force in different asymmetric postures can be explained by length of the muscle, the activation of the muscle, and the moment angle of the muscle.     

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: “Man and his Thermal Environment” By R. P. CLARK and O. G. EDHOLM. (London: Arnold, 1985.) [Pp.288.] £39·95. ISBN 0-7131-4445-9.

Abstract

A computer-video interactive system is described that enables a trained observer to systematically record and view the behaviour of athletes performing within a team-sport competition. This system is designed to allow the recall of selected video instances from previously recorded athletic behaviours. In order to accomplish this form of analysis, a computerized recording system and a video cassette recording machine were combined using specialized hardware and software. A system for the analysis of field hockey is used to exemplify how the interaction of computers and video recorders can aid in the sport analysis process.     

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: “Fuzzy Sets and Their Applications”. By C. V. NEGOIT[Abreve] and D. A. RALESCU. (In Rumanian) (Bucharest: Editura Technica, 1974.) [Pp.219.]

This paper presents a new controller for position and force control of robotic devices interacting with passive environments. In this approach, for the manipulator dynamics in joint space, suitable output equations are defined which represent the position control and force control subspaces. The dynamics of the manipulator are projected along these subspaces to obtain the dynamics in the respective subspaces. The resulting dynamics are linearized and decoupled using a nonlinear input-state linearizing controller. For the position control subspace dynamics, desirable stability features are achieved through pole placement design. Along the force control subspace, a soft base is introduced, the compliance effect of which is controlled by an appropriate compensation term. Based on the force feedback information, this compensation is modifed online using an extended dynamics. Assuming a model of the passive environment, aspects of local stability of the controller have been discussed. The theory has been presented for a two-link planar manipulator example, based on which, a numerical simulation is discussed.