The clothing for cold weather were discused. The total insulation in man is made up of sum of the insulation afforded by clothes, air and tissues. A function of clothing is to protect the body from the environment, this is especially true when himalayan expedition. Many expedition to the himalayan high altitude have had useful experiences in the textile and clothing field. Historical development and fundamental matters of clothing for himalayan expedition were explained.
The insulating properties of a fabric are due not to the fibers of the fabric itseif, but to the air trapped with in the fabric. it is impotant to realise that the thermal insulation of clothing is proportional to the thickness of the dead space air trapped within the clothing. Down clothes are extremely warm, light and comfortable.
A windproof outer layer is necessary to prevent penetration by external air. If air penetrates, clothing the trapped dead air is moved and insu1ation will diminish.
Overheating when exercising in the cold with loss of insulation associated with the production of sweat, and thus of darnp clothing, is a well recognized hazard.
It was considered that we must make every effort to be as safe as possible in clothing science field for cold environment.

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In this paper, the control methods of the refrigerants distribution by means of the electric expansion valve are discussed.
The first, various electric expansion valves are introduced. And, the super heat degree of the compressor inlet refrigerants is the control target in the recent time. The above mentioned superheat control algorithms are discussed.
The second the modern advanced technology in the control targets and the sencing system and in the dynamic characteristics are developed.
The last, I discuss the control ideas for the purpose of the harmonic control of the many electric expansion valves.

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This paper describes precise control of supply water temperature from a vapor compression chiller that is mainly used for industrial applications.
At first, it was concluded from comparison with several capacity control methods that the suction pressure control method was the most suitable. Then a chiller with this control method was developed and investigated by experiments and a computer aided simulation. The chiller is equipped with a PI controller and a magnetic linear control valve at the compressor suction line. The PI controller regulates the opening area of the valve in accordance withthe supply water temperature.
The results showed that the supply water temperature from the chiller was controlled to an accuracy within ±0.2°C for fluctuations of a cooling load or a water flow rate. Furthermore the simulation results for dynamic characteristics were in good agreement with the experimental data.

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The use of refrigerant mixture is an important subject of heat-pump technology and its research and developments have been promoted all over the world. We have tried to apply mixed refrigerants to air-conditioners, and developed an unique technology for efficiently separating and varying the mixing ratio of the refrigerants inside the refrigeration circuit. The mixed fluorinated refrigerants of R22-R13B1 were adapted to increase the heating capacity. Effects of shapes of packings and diameters of column were examined by an experimental apparatus of rectifier only, and a small rectifier with new coiled packings was developed. In the new circuit, the bottom of the rectifier is connected with condenser and evaporator by lines in parallel with expansion device. In the rectifying mode, the lower boiling-point refrigerant is stored in a reservoir connected to the top of the rectifier, and a main circuit is operated with the higher boiling-point refrigerant. Then the heating capacity, the input wattage and the fluid pressure of a heat-pump operating with the separated refrigerants are decreased to a lower level and its energy efficiency was improved through an inspection of the rectifying vapour generation method. The technique of estimating the composition of mixture operating in the circuit was developed, too, and the calculated values almost coincide with the experimetal values.

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Fundamental research was carried out on freezing process of water accompanied by blockade. Firstly, experiment on freezing using a vinyl vessel was performed. The vessel containing water was sealed and frozen in a low temperature bath. As internal presure increased, ice started to break suddenly and then continued to break frequently. Secondly, metal vessel was used and similar experiment was performed. Strain gauge was placed at eight points evenly distributed in circumferential direction on the vessel. It was found that the force acting on the vessel was so great that the vessel entered into a plastic region in very short time. It was also found that ice cracks influence the local strain value but the value is almost independent to its neighboring measurements. Approximate analysis was performed and compared with the experiment using metal vessel. The following two cases were assumed in the calculation. (1) Ice is so easy to break that the stress in the ice can be ignored. (2) Ice never break and always stay in elastic region. The experimental results laid somewhere between them but subsequently it approached the case (1).

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Air curtains are frequently placed at doorway of cold storage room or freezing chamber. As an opening of jet flow in these air curtains is relatively narrow and speed of jet flow is fast, air entrained from surroundings increases in quantity. Therefore, we consider that jet flow with narrow opening can not effectively isolate inside air from the external atmosphere, but the one with relatively wide opening can decrease air entrained from surroundings.
Then, when air curtain which has a wide opening (we call it air shutter) is installed at cold storage room, and isolating performances of air shutter are compared with the air curtain. First, as various conditions can be easily changed in numerical calculation, we compare a velocity and temperature field in cold storage room under these conditions when velocity of jet flow is changed by using numerical method.
Second, we measure a temperature and velocity distribution in an actual cold storage room under three conditions (air shutter operates, air curtain operates and no operation).
From these results, it was found that air shutter is more efficient than air curtain.

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The thermal conductivity of four binary gaseous mixtures of R22 (CHCIF₂) with R13(CClF₃), R23(CHF₃), R12(CCl₂F₂) and R114(CClF₂·CClF₂) has been measured at temperatures 298.15 and 323.15K under pressures from atmospheric to saturated pressures by a coaxial cylinder cell. The precision of the thermal conductivity obtained is within 2%. The thermal conductivity of mixtures increases with increasing temperature and pressure at a constant composition. The thermal conductivity in each mixture changes almost linearly with the concentration of R22 at a constant temperature and pressure, although the thermal conductivity at each composition is slightly larger than the calculated values by a simple molefraction average method. The experimental results were correlated with composition and pressure by empirical equations and compared with several kinds of prediction methods. The Brokaw's equation is found to reproduce the experimental data most successfully with a mean deviation of 0.7%.

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In order to enhance the heat transfer coefficient of the fin used in the finned tube heat exchanger, newly designed fin surfaces, especially, with small diameter (≅4mm) pipes are developed. The experiments are made by the transient testing technique, and used the plastic fins scaling up 4 times of the actual metal fin size. The data of the heat transfer coefficient and the pressure drop are transformed to the actual metal fin data.
The fin with the anomalous staggered pipe arrangement and the bridge-like cutting-out with inclined leg portion from stream line is found to have very high overall heat transfer coefficient which is about 1.8-fold increase in comparison with the conventional Louvered fin.
In this paper the reason why such enhancement is caused is clarified by mean of the calculation based on the rectangular duct flow. The calculated values are coincident with the data of the experiment well.

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Based on the available experimental PVT measurements reported in the literature, a modified BWR equation of state for refrigerant R115 (C₂CIF₅) is proposed. The characteristics of derived thermodynamic properties such as the isochoric specific heat capacity, the isobaric specific heat capacity and the speed of sound have been critically examined in developing the present equation. The auxiliary saturated liquid density equation, which has been used to calculate the saturated thermodynamic properties over a wide range of temperatures, is also developed. The developed equation is effective for a range of temperatures from 220K to 450K and of pressures up to 10 MPa which corresponds to the density range up to 1,244 kg/m³. Comparisons with the available equations of state are also discussed here.

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A kinetic analysis was made, in some details, of the published data showing the rates of denaturation of carp muscle actomyosin or myofibrils in the frozen KCI solution.
The logarithm of protein solubility or ATPase activity were correlated by two straight lines with different slopes in plotting against storage time. However, the first-order rate constants decreased significantly with the storage time. When the reciprocals of protein solubility or activity were plotted against storage time, a straight line was obtained throughout the almost entire storage period. The second-order rate constants were reasonably constant for the storage period. The reaction order of denaturation was approximately 3/2 to 5/2, as estimated by the differential method from the denaturation curves. The facts indicate that the reaction of freeze-denaturation in KCI solution is not of first-order, but of around second-order. The applicability of the first-order and second-order rate constants as a measure in evaluating the variables effect on denaturation was discussed.

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The heat-flow controllable heat exchanger having thermal switch ability was made to remove the humidity and to recover the heat in a plant house. The exchanger was located in a small plant house, and the humidity removal experiment and the heat recovery experiment were conducted.
As the result, it is clarified that the heat exchanger is possible to reduce the humidity in the house by using dry open air in winter. Also, the exchanger is possible to reduce the humidity only without temperature reduction in the house. Therefore, it is considered that the exchanger is available for the purpose of humidity removal and heat recovery in the plant house.

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The heat-flow controllable heat exchanger for the purpose of heat recovery through the waste hot water at the bathroom and the washing room has been developed. The system is especially available at the house of cold area and the recovery heat is used to warm the suction air conducted from ventilation device.
As the result of field test, it is clarified that the heat recovery rate by the system is very large. Also, the exchanger is possible to control the amount of recorery heat. Therefore, it is considered that the exchanger is applicable in the ventilation systems used the waste hot water.

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In recent years, the problem of unstable phenomena generated in inverter-fed induction motor has been taken up.
In this paper, at first, the effect of motor specifications on the stability of PWM inverter-fed induction motor, is investigated experimentally.
That is, the relation between the unstable phenomena and air gap length, rotor resistance and moment of rotor inertia, is studied.
Next, a method for preventing the growth of unstable phenomena in inverter-fed compressor motor is proposed.
By this method, unstable regions are eliminated from the range of practical driving.
Features of this method are illustrated.

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