Axial force of the bolt is very important for structural stability. To obtain stability of the structure, axial force of the bolt should satisfy the specification and be maintained over the time. Hence, It is important to the axial force of the bolt is measured and it manages. However, measuring of the axial force using sensors is very expensive. Torque method using frequently in the field is difficult to confirm accurately by the torque coefficient change. In this study, measuring of axial force using elastic force of the spring washer was studied. First, the relational formula is drawn about the pressure in which the spring washer model changes to the annular of the plane state. According to the axial force of the bolt, the necessity height of the spring washer is presented and the finite-element analysis model is recommended. The analysis model research, generally, the axial force of high strength bolt is confirmed. It expands to confirmation of the large caliber bolt.
The purpose of this study was to examine laundry behavior according to the number of households and the type of washing machine that each household used. The data was obtained from questionnaires filled out by 417 households, which included college students living in Seoul and Gyeonggi province. The results of this study are as follows: first, according to the results of survey about the number of household members and type of washing machine that household had, one or two-person households accounted for 24.0%. Regarding the type of washing machine that each household used, there were more drum washers. In households comprised of three or more persons, a higher percentage had a machine with a pulsator. Second, with regard to the method of classifying the wash in doing the laundry, all families classified the wash according to color and textile material. Third, with regard to the amount of detergent in doing the laundry, 63.5% of households used the recommended amount of detergent while 28.3% of households used more detergent than the recommended amount. Fourth, with regard to the set temperature of water in doing the laundry, 36.2% of households used cold water; this was the highest percentage. Fifth, with regard to input sequence in doing the laundry, most households put the wash in the machine in advance, and then filled the washer with water; 56.1% of households added a rinsing process for all washing processes.
The purpose of this research is to provide accurate information of household washers and detergents for consumers, so that help the producers who make washing machine and detergent to get basic material and also help consumers to choose washing machine. Experiment was proceed with two type of washers to compare energy consumption, washing performance, rinsing effectiveness further, damage caused by entanglement of laundry and fabric was assessed. Detergent P and T were used to compare the performance related to differences of ingredients of detergent. Soiled fabrics of EMPA 108 set were used to evaluate performance of washing by different types of contamination. A summary of experimental results are : First, for the consumption of water, drum-type washer consumed 53% less than pulsator-type washer. On the other hand, the washing time was almost similar for both these machines, but pulsator-type washer showed shorter progress, implying that power saving was more efficient in this case. Second, the drum-type washer showed better performance for contamination with all types of detergent, but the pulsator-type washer showed better rinsing performance. Third, the drum-type washer performed less data of tangle level and fabric damage. Fourth, detergent "P" exhibited better washing performance than did detergent "T", regardless of the type of soil. And with no limit of detergent variety, water-soluble protein soil showed high removal rate, liposoluble soil especially pigment was hardly removed.