The Industrial Revolution, which began in England at the end of the eighteenth century, resulted in “affluent society,” characterized today by mass production and enormous consumption. On the other hand, accelerated by population increases and its accompanying enlargement in energy consumption, the environment started to deteriorate, calling to the minds of people the problems concerning the global environment. One such cause is people's desire to seek convenience and comfort in the broad sense. Today, having realized the limitation of what the global environment can endure, the very basics to sustain the continuation of life of all species, inclusive of mankind, is to grasp accurately the condition under which we live and to look into the future with a firm decision to divert ourselves from the lifestyles and habits that we have been accustomed to In other words, such diversion extends to matters pertaining to the lives of individuals, their awareness of others and surrounding conditions, their criteria for values and quality of life. Once having taken note of these, in order to clarify the various problems concerning people and their environments and to provide solutions for them, one must be able to maintain a system to accumulate and analyze data, open them to the public, and to forecast the future, to propose, to guide and to direct to the solution, which will be widely and easily accepted by society. By doing so, we hope to create a society where people can enrich a sense of humanity and share the responsibility of mankind.
ET*, an index adopted as ASHRAE standard (ASHRAE.1992) to evaluate thermal environments, is used widely for evaluation, design and control of such environments. This paper deals with the originality and characteristics of ET*. It also explains how problems of ET* that have been identified influence the practical use of this index, and identifies matters that require attention with regard to such problems, based on the results of experiments conducted for subjects in the sedentary posture.
PMV (predicted mean vote) defined in ISO-7730 is widely used for evaluation, design and control of thermal environments. This study discusses the physical meaning of thermal load defined mainly by PMV, based on the heat balance equation between the human body and the environment, and verifies the thermal load, heat resistance between the skin and the environment and response to thermal sensations from the results of testing a subject in the cold-neutral thermal environments. This paper also presents the limits of application of PMV and qualitatively analyzes the influence of its use outside the comfort range.
This study measured the energy requirements for load carriage on uphill, level and downhill grades. These field data were used to test our algorithms for estimating the energy cost of load carriage. Volunteers carried pack loads of 0 kg, 13.6 kg or 27.2 kg as they walked on level and downhill grades of 0%, 4%, 8.6% and 12% at 1.34 m·s−1. Subjects attempted carries on the uphill 8.6% grade with all 3 loads and on the uphill 4% grade with empty packs. Oxygen uptake (VO2) was collected using portable oxygen monitors. Mean values for VO2 increased as uphill grades and load increased, and decreased with negative grades. The mean subject weight (80.2 kg) was used to calculate load carriage energy costs which were multiplied by a terrain factor of 1.1. The data were split into 5 subsets for statistical analysis: all negative work and level data by load, all level and uphill data with zero load, and all loads on the 8.6% uphill grade. Predicted energy costs using algorithms for level, downhill and no-load uphill carriage agreed with the field data.
In the initial report of the research (Kohri and Mochida, 2002), a new calculation method of the dispersed two-node model was proposed. Then, we attempt to construct a new evaluation process of the thermal environment in the vehicle using the dispersed two-node model. In the middle phase of new vehicle development, the prototype test is important to improve detailed performance. At this phase, the structure designers of air-conditioning system have to measure the thermal properties in the cabin so that they improve and modify to achieve aimed performance. Thus such as this experimental evaluation technology is essential. The new process consists of three parts, 1) Measurement and calculation of thermal characteristic of the prototype, 2) Calculation of human heat balance with the dispersed two-model and 3) Prediction of thermal sensation vote. This report is mainly concerned with 1) and 3), because the contents of 2) was included in the initial report. Firstly, the detailed calculation method of radiant heat properties is described, and the measurement method of convective heat properties is explained. Next, the prediction method of SET* of regional body compartment and whole body, the concept of the latter was suggested by Gonzalez et al. (1974), using the dispersed two-node model is described. Then, the correlation between SET* and the thermal sensation vote is identified based on the experiments with subjects. Finally, applying this process to the improvement of the vehicle thermal environment, it is confirmed that this method is useful and practical for the development of the vehicle air-conditioning system.
Lighting designers have long accepted Kruithof's proposal that warm lighting is preferred over low intensities of illumination, and cool lighting is preferred over high intensities of illumination. However, when considering these preferences in color temperatures, Kruithof's proposal does not take into account seasonal changes or differences in age. Kakitsuba et al. (2000a, 2000b, 2003) demonstrated a seasonal change in color temperatures preferred by young Japanese subjects aged between 19 and 27 under illumination intensities of 200 lx and 1,500 lx, and an age difference in preferred color temperatures when the results were compared with those obtained for eight Japanese female subjects aged between 36 and 45 under an illumination intensity of 1,500 lx. Following these studies, the same middle-aged female subjects were exposed to 3,000 K and 7,500 K in controlled room temperatures of 22°C and 30°C. The illumination intensity was set at 200 lx on each occasion. Following controlled exposure for 30 min. at 25°C in a darkened room, subjects were exposed to given lighting and thermal conditions. Skin and oral temperatures, ECGs and blood pressures were measured throughout the exposures. At 15 min. intervals the subjects reported on comfort, calmness, brightness and thermal sensations. The resulting changes in HF values indicated that the subjects preferred 7,500 K to 3,000 K. This demonstrated that Kruithof's proposal could be accepted for middle-aged female subjects in the case of 200 lx as well as 1,500 lx.