• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.7
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• pp.4463-4468
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• 2014

To increase the efficiency of a solar module, the development of solar concentrator using a lens or reflection plate is being proceeded actively and the concentrator pursues the a concentration using a lens or an optical device of a concentration rate and designing as a solar tracking system. On the other hand, as the energy density being dissipated as a heat according to the concentration rate increases, the cares should be taken to cool the solar concentrator to prevent the lowering of efficiency of solar cell by the increasing temperature of the solar cell. This study, researched and developed an economical concentrator module system using a low priced reflection optical device. A concentrator was used as a general module to increase the generation efficiency of the solar module and heat generated was emitted by the concentration through the cooling system. To increase the efficiency of the solar concentrator, the cooling system was designed and manufactured. The features of the micro cooling system (MCS) are a natural circulation method by the capillary force, which does not require external power. By using the potential heat in the case of changing the fluid, it is available to realize high performance cooling. The 117W solar modules installed on the reflective plate and the cooling device in the cooling module and the module unit was not compared. The cooling device was installed in the module resulted in a 28% increase in power output.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.27-34
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• 2018

Recently, liquid desiccant systems have received attention for the dehumidification of air. LiCl and LiBr are widely used in liquid desiccant systems due to their excellent thermo-physical properties. In this study, dehumidification tests were conducted with Celdek elements using LiCl and LiBr. During the tests, the dry and wet-bulb air temperatures were maintained at $35^{\circ}C$ and $28^{\circ}C$, respectively. The solution temperature was $20^{\circ}C$, the solution concentration was 50%, the solution circulation rate was 50 kg/h, and the frontal air velocity was varied from 2.0 to 4.0 m/s. The results show that the amount of dehumidification increased as the frontal velocity increased. On average, LiCl showed 27% higher dehumidification performance than LiBr, which was probably due to the lower saturation of the absolute humidity of LiCl compared with that of LiBr. On the other hand, LiBr yielded 12% larger pressure drop than LiCl. In general, the Sherwood numbers of LiCl and LiBr were approximately the same, showing that the effect of the desiccant on the Sherwood number was insignificant. Existing correlations highly overpredicted the present Sherwood numbers.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.176-186
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• 2017

The subject of this study is to search for the improvements or solutions of problems in the field of the performing arts that relies on public support and faces economic difficulties. Considering the value chain for the performing arts industry is comprised of Creation-Distribution-Consumption is isolated relatively, this study aims to identify improvements for the distribution system. By examining the government's theater-oriented support policy, this study details methods of improvements in the distribution sector of the performing arts industry. Following the study of the performing arts industry and its value chain, the study analyzes the structure, factors and the present state in the performing arts industry, as well as the volume and type of public sector support for distribution. The study concludes by suggestingmagnifying government's Distribution sector supporting that was limited by only 2.7% in 2014, and fostering and specialty improvement of circulation agents such as production agencies.In addition, supporting distribution diversification, namely the extension of platforms like the Visualization of Performing Arts, is needed. These alternatives will contribute to balanced development and coevolution of each sector which comprises the performing arts industry's value chain.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.3
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• pp.1448-1457
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• 2014

Geriatric illness is increasing with aged population ratio due to a prolonged average life span. Research studies with therapeutic approach using oriental herbs have been attempted, but the very few studies of oriental herbal tea as a healthy drink have done as a health care. This study was performed to identify the effects of oriental herbal tea on the physiological function and behavioral change of elders at geriatric facility. A quasi-experimental design using a nonequivalent control group, pre-post test was used. Total 38 of elderly population (20 of experimental group and 18 of control group) was recruited. 100mL of a type of oriental herbal tea developed for this study was given to each subject 3 times a day for 30 days (from May to June 2013). The health scan analyzer and questionnaire for behavioral change were used to measure dependent variables. The data was analyzed by SPSS/WIN 18.0. After drinking the oriental herbal tea, more significant improvement on blood circulation (t=-4.466, p<.001), liver function (t=-2.855, p=.007), brain function (t=-2.545, p=.015), bone density (t=-6.125, p<.001), blood sugar (t=-4.180, p=<.001) and emotional factor (t=2.389, p=.023) as the sub-variable of behavioral change were found in the experimental group than control group. This study shows that oriental herbal tea can be effective on the physiological function and emotional relief of the elders. Therefore the tea can be utilized as an effective intervention for the health of elders in geriatric facility.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.5
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• pp.2206-2211
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• 2012

To identify the effect of the aroma foot spa on the stress, 12 university students with stress were divided into control group (6 subjects) and aroma foot spa group (6 subjects). Control group was not subjected to any kind of intervention while aroma foot spa group was subjected to 10 minutes of foot bath using 5% Juniper, lavender and lemon essential oil and 10 minutes of foot massage using massage cream during four weeks, two times per week. As for the evaluation method, brain wave was studied to measure the amount of change in stress. After measuring the change in the brain wave before and after the experiment, it was proven that the aroma foot spa group s Alpha wave (Z=-2.364, p<.05) and SMR wave (Z=-1.981, p<.05) were higher than those of the control group. Moreover, when the pre and post experiment results of the aroma foot spa group were measured, it was proven that the Theta wave (Z=-2.366, p<.05) decreased while Alpha wave (Z=-2.371, p<.05) increased. In other words, aroma foot spa that included foot bath using essential oil and foot massage increased Alpha wave which in turn influenced the brain wave due to increased blood circulation resulting from muscle relaxation. Moreover, SMR wave increase was closely related to the change in Alpha wave, which demonstrates that SMR wave increased due to stress alleviation. Accordingly, it may be possible to assume that aroma foot spa is effective in relieving stress.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.251-259
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• 2016

This study examined the DO concentration distribution and ORP distribution using microbubbles on pilot-scale aeration tanks. As a result of MLSS mixing and oxygen transfer phenomenon using microbubbles, different DO concentrations were observed depending on the circulation of the liquid with the microbubble supply location on the lateral of an aeration tank. The simulation results of CFD (computational fluid dynamics) program showed that MLSS mixed with a microbubble supply in the middle the reactor is much better than on the left side of the reactor. A single reactor containing an anaerobic, anoxic, and aerobic zone, was evaluated without partition according to the location of the microbubble supply based on the experiments and CFD analysis. MLSS was separated into solid-liquid by the microbubble supply in the aeration tank. Consequently, selecting the appropriate microbubble size is important for MLSS mixing and was maintained at the proper DO concentration for biological treatment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.325-331
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• 2016

Computational fluid numerical analysis using the commercial code CFX was performed to develop a Pelton turbine for a pico hydro power generator using the circulating water of a cooling tower in a large building. The performance of the Pelton turbine was examined for different design factors, such as the bucket shape, in which the Pelton wheel was connected in an appropriate manner to the pipe section, and the number of buckets in order to find the optimal design of Pelton turbine for a pico hydro power using surplus water. A benchmark test was carried out on the manufactured small scale Pelton turbine to validate the design method of the Pelton turbine by numerical analysis. The results obtained by comparing the flow characteristics and power output measured using the ultrasonic flowmeter, the pressure transducer and the oscilloscope with the numerical results confirmed the validity of the analytical design method. The possibility of developing Pelton turbines for kW class pico hydro power generators using surplus water with an average circulation velocity of 1.2 m/s for the chosen bucket shape and number of buckets in a 30 m high building was confirmed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.390-395
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• 2019

Hydrogymnastics so that sufficient exercise effect can be obtained using the resistance of water has a positive effect on patients who have to receive arthritis or rehabilitation treatment. However, the studies on the effect are insufficient, and the main cause of their effects has not been unclear yet. In this study, in order to identify the main cause of the effects of Hydrogymnastics, conducted Unsteady fluid flow simulation under the same conditions as the actual environment. The analysis model based on real hands, and the pressure fluctuation applied to the knuckle was analyzed by the computational fluid method. During the underwater movement of the hands, Various sizes of vortices were generated between fingers due to skin surface velocity and flow resistance. Pressure of about -500 Pa to +500 Pa is applied by the vortex flow. Also It was confirmed that the positive pressure and the negative pressure were continuously repeated up to maximum + 2000 Pa at the minimum of -2000 Pa at the portion where the direction was changed. Pressure fluctuations with a frequency of 20 Hz to 70 Hz were added continuously for each knuckle. These continuous pressure fluctuations provide a direct massage effect on the knuckles, an It is judged that the blood circulation at the relevant part is positively affected.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.239-244
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• 2018

A 59-year-old man with no specific medical or family history complained of chest pain and became unconscious. A member of his family, who was a witness, called 119 and gave him dispatcher-assisted cardiopulmonary resuscitation, followed by defibrillation using an automated external defibrillator placed in his apartment. Afterward, he was given two sessions of defibrillation by the 119 emergency squad, then transferred to an emergency medical center with the return of spontaneous circulation. The patient was discharged with cerebral performance category (CPC) 1 15 days later. While dispatcher-assisted cardiopulmonary resuscitation and defibrillation is at its beginning stage in South Korea, this case seems to demonstrate its effectiveness. Moreover, this case suggests it can be particularly useful for helping untrained witnesses use an automated external defibrillator, which may have important implications in regions in which there are delayed responses of the 119 emergency squad to the site. It is also important to develop a plan for improving witness access to and quantitative supply of the South Korean public access defibrillation (PAD) program.

• Journal of Korean Library and Information Science Society
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• v.5
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• pp.119-168
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• 1978

This is a survey of the reserved book system in the pilot universities in Korea. We have surveyed only 22 university libraries among 29 pilot schools as of 1977, because of the differences in the library users, library organization, library facilities, and library materials between universities and colleges. In 1972, the Korean Ministry of Education developed a reformation plan for their higher education based on the teaching method of curriculum-oriented faculty instead of that of the faculty-oriented curriculum. The former puts emphasis on the cultivation of a student's thinking, creativity, and judgement through self-teaching to do a given assignment. The reserved book system in a college or university library is one of the most important methods necessary to accomplish the above educational aim. The survey used a questionnaire with 50 question on 28 items concerning the various aspects of the reserved book system in 22 pilot universities. the survey result discovered many problems needing correction. The following list describes the measures needed to correct the problems found in the pilot universities. 1. The management of a centralized reserved book system is much more effective and economical than the decentralized reserved book system when a university is located on the same campus. 2. In the university library, an independent reserved book department requires to gain the desired educational aims as compared with the reserved book room controlled by any other department in the library. 3. The reserved book system should not be adopted by all the departments at once but enlarged gradually, for it needs the understanding and support of faculty members and the university itself. 4. As competence is essential to the effective operation of the reserved book room, the university library should not place an unqualified person in charge of the reserved book department. 5. The librarian in charge of the reserved book department is required to do more professional works such as analysis of users, collection and analysis of syllabuses, maintenance of faculty member cooperation, establishment of measures to acquire unavailable materials, and drawing up an effective management plan. However, he is spending most of his time in clerical works, that is, non-professional works. 6. Three to five titles of each reserved book are considered reasonable and required materials should be shelved in proportion to the number of students, that is, one copy per eight or ten students if the materials are allowed to lend for two hours at a time. For the supplementary materials, the library needs to place two or three copies per subject. 7. Professors must select reserved books with care so that they can be used year after year. 8. Few universities are asking professors the number of class students and the date when the reserved material will no longer be needed on reserve. 9. The library should gather all the lists of reserved books from every professor at least three to five months before the courses open, because it takes a long time to obtain foreign materials. 10. It is desirable that the reserved book department should collect the lists and prepare the materials with promptness and consistency. 11. Instead of block buying, it is desirable to purchase reserved books at the time the library gets the reserved book list from the professors. The library should also inform faculty members whether it obtained each reserved book or not before the course open. 12. The library should make a copy of materials if a professor requires to reserve an out-of-print book or partial contents of a book, journal, and thesis. 13. An independent budger for reserved books from the budget for general materials is desired. 14. The shelf arrangement of reserved books by courses or professors under the same department is much more preferable than a classified arrangement. 15. While most of the universities adopted the open shelves system for all the reserved books, it is more effective and economical to take a compromise system, that is, closed shelves for requires materials and open shelves for supplementary materials. 18. Circulation of reserved books needs a different system between required materials and supplementary materials: two or three hours and/or overnight loan for the former and two and/or three days loan for the latter. 17. A reserved book room should be open a long time after class so that students can have sufficient time to use the room. 18. The library must take daily and monthly statistic as well as statistics on every aspect of the reserved book system in order that the library ma decide on policy and management of the reserved book room in collaboration with the university. Furthermore, regular reports on the use of the reserved book room should be made to the president and the executive council by the library to acquire their understanding and cooperation for the reserved book system. 19. Cooperation of faculty members is indispensable to the effective management of the reserved book department and it is desirable to make a committee which will fix various decisions about the system. Whenever the director of the library make his decision, he must consult with his staff in order to involve them earnestly in the operation of the system.