Naoshi Kakitsuba

Ventilation index of helicopter pilot suits

The main function of helicopter pilot suits used in offshore flights is to provide thermal protection in the event of cold water immersion and to allow maintenance of thermal comfort during normal use. As part of a larger study to assess the thermal characteristics of helicopter pilot suits, the ventilation index of four suits was determined using the methods outlined by Birnbaum and Crockford (1978). These methods involved determining the microenvironment volume and the rate of air exchange of the protective clothing assembly. Results showed that in the standing motionless subject, the Nomex and Cotton Ventile suits had the higher ventilation indices of 1·53 and 0·91 litres.min−1, while the Nomex/Insulite and Goretex suits had substantially lower ventilation indices of 0·07 and 0·03 litres.min−1. These ventilation indices are due to the fabrics used in construction and the design of the suit.

Comfortable Indoor Lighting Conditions Evaluated from Psychological and Physiological Responses

ABSTRACT Comfortable indoor lighting conditions were examined for psychological and physiological responses. Ten Japanese males participated in a series of experiments. They were exposed to light emitted from fluorescent lamps of 2700 K in the range of 20–170 lux and of 1500–3000 lux, 3000 K in the range of 50–200 lux, 3500 K in the range of 100–200 lux and of 1200–1800 lux, 4200 K in the range of 150–550 lux and of 2500–4000 lux, and 5000 K in the range of 200–500 lux and of 3500–5000 lux and underwent two trials at 10:00 am and 5:00 pm on the same day. Illuminance at a given correlated color temperature (CCT) was first controlled at the lowest value in the designated range and then increased in a stepwise manner. On reaching the highest value in the range it was then decreased to the lowest value in a stepwise manner. Participants were required to indicate their perception of brightness, glare, and comfort at the controlled illuminances. Electrocardiogram and electroencephalogram data were monitored continuously throughout exposure. The results showed that the boundary illuminances estimated from psychological responses were not significantly different from those estimated from physiological responses. A comfortable lighting zone is expected to be a belt-shaped zone in the combination of illuminance and CCT.

Physiological responses to changes in relative humidity under thermally neutral, warm and hot conditions

Four hypothetical thermophysiological responses to changes in relative humidity (Rh) under thermally neutral, warm, and hot conditions were proposed for a person at rest. Under thermally neutral and warm conditions, the first hypothetical response to an increase in Rh was a decrease in mean skin temperature (T¯sk) due to increase in mean evaporation rate (E¯sk), and the second hypothetical response to a decrease in Rh was a decrease, an increase, or no change in T¯sk, depending on changes in the E¯sk. Under hot conditions, the third hypothetical response to an increase in the Rh was an increase in T¯sk or decrease in T¯sk upon decrease in the Rh due to changes in E¯sk, and the forth hypothetical response to an increase in Rh was an increase in T¯sk due to increase in the peripheral blood flow rate (SkBF). To test these hypotheses, the T¯sk and E¯sk of four young male volunteers were measured at 28°C, 30°C, or 32°C while the Rh was maintained at 40% or 80% Rh for 60min after 20min exposure at 60% Rh (control condition). In a second experiment, the T¯sk, E¯sk, and SkBF of five young male volunteers were measured at 34°C-40% Rh or 36°C-40% Rh, or 34°C-70% Rh or 36°C-70% Rh for 60min after 20min exposure at 28°C-60% Rh (control condition). The first hypothesis was partly supported by the findings that the T¯sk was lower than the control values at 28°C-80% Rh and the E¯sk was higher than the control values at 80% Rh at any tested temperature. The second hypothesis was partly supported by the findings that the T¯sk was lower than the control values at 28°C-40% Rh, and there were small changes in both T¯sk and E¯sk at 30°C-40% Rh. The third and fourth hypotheses were supported by the findings that the T¯sk at 36°C-70% Rh was significantly higher (p<0.01) than at 36°C-40% Rh, the E¯sk was significantly higher (p<0.01) at 70% Rh than at 40% Rh, and SkBF was positively correlated with T¯sk.

A STUDY OF STANDARDIZING THE INSPECTION SHEETS FOR EVALUATION OF QUALITY OF BUILDING MAINTENANCE

正田浩三ー ーーーー * 1 垣鍔 直ー ーーーー* 2 キーワード: ビル管理,美観度,アンケート調査

Author’s Reply to Review of a Published Article

Address correspondence to Naoshi Kakitsuba, Meijo University, Shiogamaguchi 1-501, Nagoya 468-8502, Japan. E-mail: naoshi@meijo-u.ac.jp First of all, I would like thank Professor Fotios for his interest in my study. In this reply I have endeavored to address his questions and comments. Regarding the number of points on the rating scales, in Japan, a 7-point brightness scale and 5-point scales for glare and comfort are quite popular. Using 8-point or 6point scales may be possible but mistranslation into Japanese should be avoided. In addition, these scales were selected to facilitate comparison with the work of other Japanese scientists. About scale construction, excuse me for my careless mistake in the original description of the scales, which was unintentionally misleading. Although I listed the scale with labels in table 2 of the original article, the voting sheet did not show word descriptions for each of the numbers on the scales. In fact, semantic differential scales were used as shown in Fig. 1. “Neutral” was intended to mean “neither slightly dark nor slightly bright.” I should not have translated the scales when reporting the results. About levels of brightness, although I understand that “very bright” may be a desirable level of light, I think that it is highly dependent upon the activities taking place in the environment being considered. In the condition where people work with computer displays, reading, and drawing, very bright may be the desirable level of light. If people are in relaxed setting, then very bright conditions are less likely to be comfortable. The comfortable range is expected to be quite wide and also quite dependent on activity. This is my basic concept, which was written in the text. The participants were inactive during the experiment and engaged in no tasks. If the participants had engaged in some tasks during the experiment, the results may have been different. As stated in the Discussion section of the article, different results can be expected under different experimental conditions. It is a true statement that the low boundary illuminance was identified as when the subjects voted “neutral” for brightness and comfort, and the high boundary illuminance was identified as when the subjects voted neutral for the glare and comfort sensation. To determine the boundaries, I relied on change in brightness for low boundaries and glare for high boundaries together with a change in comfort sensation. However, a change in comfort sensation was sometimes too small to identify the boundaries clearly. Therefore, it was supplementary information.

Effect of Morning Bright Light after Waking on the Morning Rise in Core Temperature

ABSTRACT This study tested the hypotheses that 2-h exposure to morning bright light after waking may avoid a delay in nadir time for individuals who experience delayed nadir time after waking and may improve the morning rise in core temperature (Tc) due to residual effects of morning bright light on body temperature regulation. Eight young men were exposed to 110, 1000, and 4000 lx light for 2 h after waking at 7:00 AM. After 2-h exposure to a given illuminance, illuminance was controlled at 1000 lx until 12:00 PM. Rectal temperature (Tre) was measured as a proxy for Tc continuously from 12:00 AM on the prior night to 12:00 PM on the day of the experiment. To estimate body heat balance, skin temperatures and values for regional dry heat loss at seven sites were continuously measured from 8:00 AM to 12:00 PM, together with measurement of oxygen consumption and finger skin blood flow rate (SkBF) from 8:00 AM to 12:00 PM at 1-h intervals. Results indicated delays of a few minutes in nadir time with 1000 and 4000 lx, as opposed to a 120-min delay with 110 lx. In addition, Tre increased after 2-h exposure to 4000 lx light, probably due to the significantly (P < 0.01) lower mean skin temperature, SkBF, and dry heat loss compared to the other lighting conditions. Light exposure over 1000 lx may thus avoid substantial delays in nadir time, and light exposure over 4000 lx could restore Tc rhythm in a prompt manner due to residual effects of morning bright light on body temperature regulation.

Quantification of mental sweating using a flight simulator

We attempt to quantify mental excitement in a VR environment. Specifically, the study tracked the amount of water evaporating from the palm over time as the subject maneuvered a flight simulator application, engaging in simulations of difficult or dangerous flights. The consumer software application Fight Simulator 98 (VR) was used as VR content on a PC running Windows 98. In this simulation, the flight begins at Tokyo Haneda Airport, where a jumbo jet takes off toward the south, rising in altitude. The subject is free to select from several stimulating or dangerous flights in advance, and is free to maneuver the plane as its pilot. This thrilling flight is not entirely realistic, although the plane takes off and lands in a specified airport with a real-world counterpart. The volume of water measured from the skin of all five subjects increased synchronously with the thrilling flight, though with some individual variations in volume. This phenomena were considered to represent episodes of mental sweating. Thrilling flights in a flight simulator /spl rArr/ fear of crashing /spl rArr/ neural arousal (rapid responses of visual and motor fields) /spl rArr/ excitation of hypothalamus /spl rArr/ (increased) blood flow of capillary arteries of the skin /spl rArr/ (increased) volume of water from the skin. Current game systems are unable to sense player excitement. Interactive VR systems or game systems with programs capable of detecting player arousal have many potential applications.