This is the second part of lecture courses entitled "Heat Transfer in Too Short." In the first part of this lecture published on Vol. 2, No. 1 of this Journal, the fundamentals of heat transfer are described. The contents of the first part are; 1. Temperature, and Heat Transfer, 2. Three Modes of Heat Transfer, 3. Heat Conduction, 4. Convective Heat Transfer, and 5. Concluding Remarks. This second part is devoted to heat transfer accompanied with transport of mass. Transport of mass is very important in the temperature regulation by perspiration from a human body exposed to a hot environment. The main contents are; Introduction, Definition of Concentration, Partial Pressure and Humidity, Fick's Law, Convective Mass Transfer, and Analogy between Mass Transfer and Heat Transfer.

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Update knowledge on thermoregulatory functions and thermal adaptability of the young and old of both sexes is surveyed. In part 1, that from birth to preadolescence is discussed. Newborns are characterized by a relatively large surface area, thin skin and subcutaneous fat, and insufficient thermoregulatory responses, making their thermoneutral zone warmer and narrower, compared to adults. On the other hand, well-developed brown adipose tissue plays an important role in newborn thermogenesis. Sweating function has been developed in newborns, in whom, however, thermal threshold is high and sweat-secretory capacity is poor. The central thermoregulatory mechanism is assumed not to be fully developed at birth, and fever is not induced by infection in neonates. Cutaneous vasomotor response is even stronger in children than adults, whereas it is not clear whether sweating activity is greater in children or not. Thus the thermoregulatory significance of dry heat loss is greater in children than in adults. Infants and children are more predisposed to heat disorders because they are more susceptible to heat congestion and to dehydration. They are acclimatized to heat more slowly and to a less degree than adults.

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The Great Hanshin Earthquake occurred at dawn on Jan. 17, 1995. Of the great damage brought about by the earthquake, we reviewed that sustained by residential buildings and studied the causes of damage to old wood-frame housings which suffered particularly severe damage. Based on these studies and discussions, we proposed general measures for earthquake damage prevention while focusing on the process of construction of residential buildings.

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The purpose of this paper is to find out the amount of relief from human solar heat load and thermal comfort afforded by tree shade in an urban garden in summer. A pre-observation was carried out to measure air temperature distribution as characteristics of the urban climate in Nagoya. The lower temperature zone was found around TSURUMAI garden and HIGASHIYAMA park. Six different types of sites, TSURUMAI garden and its neighboring area, were selected as the experiment sites. The experiments were conducted from 22 to 29 August, 1994 to find the relationship between climatic conditions and human responses. Climatic conditions, and subjects' thermal sensation were measured. Thermal comfort is affected by solar radiation in an outdoor environment. Radiant heat exchange on the human body was estimated on the basis of the measured air and surface temperature, and solar radiation. The operative temperature was modified with the effect of the radiant heat exchange. New effective temperature was calculated with the modified operative temperature. There were significant differences between sunny places and shady places in the park, and the urban canyon in the thermal sensation under equivalent new effective temperature ET^* conditions. The effect of tree shade on thermal comfort was verified in this study.

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The purpose of this paper is to evaluate the influence of non-uniform thermal radiation environments on the human body under equal operative temperatures. Experiments were conducted to find the effects of geometries between the human body and a radiant heating panel on the human skin temperature and thermal sensation. The operative temperature was set at 28℃. Six kinds of the panel position in relation to the human body were used for keeping an equal configuration factor between the panel and the body as an experimental condition: combinations of front-side-rear positions and upper-lower positions. At the lower-front condition the mean skin temperature rose to 0.8℃ during expose time. In the upper condition, the mean skin temperature was most apparently influenced by radiation from the front . In the side condition, instep skin temperature begun to rise after 20 minutes from the beginning of exposure. In the upper condition, the thermal sensation of the whole body did not depend on the panel direction, but in the side condition, the thermal sensation vote fluctuated from a hotter vote to a colder vote during the exposure time. In the lower-rear condition, the thermal sensation represented a colder vote than at the other positions. The partial operative temperature correlated to the thermal sensation of a part of the body.

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As compared with adults, children have been reported to have a less effective thermoregulatory capability during exercise in a hot climate. This study was undertaken to investigate the thermal responses and heat balance of children at rest during exposure to heat and wind. Ten prepubertal boys and 8 male graduate students served as the subjects during the summer. Each subject first rested in a thermoneutral room [air temperature (Ta) 28℃, relative humidity (Rh) 50%, air velocity (V) 0.2 m/s] and then moved to a hot room (Ta 35℃, Rh 70%, V 0.2 m/s) and stayed for 1 hour. They were then exposed to wind (V 1.0 m/s) from a fan placed in front of them for an additional 30 minutes under the same temperature and humidity conditions. Total sweat rate (Msw, t), local sweat rate (Msw, l) and the numbers of heat activated sweat glands on the back and the upper arm, rectal temperature (Tre), skin temperatures at nine sites and metabolic rate were measured. The numbers of heat activated sweat glands on both the back and upper arms of the boys were significantly greater than that of the men, although both the Msw, l and Msw, t were similar. The mean skin temperature (Ts) of the boys was significantly higher than that of the men during the heat exposure, although the change in Tre among both groups was similar. The metabolic rate, radiative and convective heat losses and heat balance for both groups were also similar except for dry heat loss during exposure to the wind. The dry heat losses of the boys were significantly greater than those of the men. These results suggest that the thermoregulatory ability of prepubertal boys during heat exposure is similar to that of the men.

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The effects of local heating on physiological and psychological thermal responses were examined. Four healthy female students were used as subjects in a climatic chamber controlled at 31℃ and 50% r.h. The skin temperature beneath the heating pad increased significantly. The increase in temperature of other regions varied significantly, with the largest increases being found during abdomen and loin heating. The tympanic temperature (T) rose or remained unchanged during local heating. Relatively greater increases in were recorded during forearm, foot and upper arm heating. No transient falls in were noted. The sweating rates of the dorsum of the hand and the thigh increased during local heating of any body region, particularly upper arms, abdomen and forearm. The effects of peripheral heating extended to the central and peripheral parts of the body surface, but the heating of the central parts affected the skin temperature of those parts only. The physiological and psychological thermal responses were different depending on the body region heated. The influence of heating of the upper extremities was greater than that of the central part of the body.

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