• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.728-734
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• 2016

The improvements of living and lifestyle have led to the increased sales of frozen milk products, such as soft ice cream or slush. These frozen milk products are commonly made in small refrigeration machines. R-502, which has long been used as the refrigerant in soft ice cream machines, is being replaced with R-404A due to the ozone layer depletion issue. In this study, an optimization and performance evaluation were conducted on a soft ice cream machine with a freezer volume of 2.8 liters. The optimization focused on the appropriate refrigerant charge and expansion valve opening. Under the optimized conditions, ice cream was produced in 10 minutes and 5 seconds, and the COP was 0.57. The performance tests included ice cream sales with no interval, ice cream sales with 30 second intervals and under extreme outdoor conditions. The results showed that 20 sales were possible with no interval, and infinite sales could be made with 30 seconds intervals. Ice cream sales were also possible under summer or winter outdoor conditions. The present results may be used for the design of food refrigeration machines as well as to optimize other refrigeration cycles.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.9
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• pp.526-535
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• 2018

Recently, in order to reduce the $CO_2$ emission in the island area, countermeasures to operate power system in a stable manner are being researched due to decrease of the operation rate in diesel generators and the increase of renewable energy sources. The phenomenon of energy sinking can be occurred if the output of renewable energy sources is larger than customer loads. Voltage of CVCF(constant voltage & constant frequency) battery could be increased rapidly according to the condition of SOC(state of charge) and blackout could be occurred due to shut-down of CVCF inverter, at carbon free island micro-grid based on the CVCF inverter. In order to overcome these problems, this paper proposes a transient operation algorithm in CVCF based micro-grid which in advance prevents shut-down of CVCF inverter during the energy sinking. And also this paper proposes the modeling of micro-grid including CVCF inverter, PV system, customer load using PSCAD/EMTDC S/W. From the results of micro-grid modeling based on the proposed algorithm, it is confirmed that CVCF based micro-grid can properly prevent shut-down of CVCF inverter according to SOC and battery voltage of CVCF inverter when energy sinking is occurred.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.6
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• pp.1047-1055
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• 2006

We patterned nano-width lines on a super hard bulk diamond substrate by varying the ion beam current and ion beam sources with a dual beam field ion beam (FIB). In addition, we successfully fabricated two-dimensional nano patterns and three-dimensional nano plate modules. We prepared nano lines on a diamond and a silicon substrate at the beam condition of 30 kV, 10 pA $\sim$ 5 nA with $Ga^+$ ion and $H_2O$ assisted ion sources. We measured each of the line-width, line-depth, etched line profiles, etch rate, and aspect ratio, and then compared them. We confirmed that nano patterning was possible on both a bulk diamond and a silicon substrate. The etch rate of $H_2O$ source can be enhanced about two times than that of Ga source. The width of patterns on a diamond was smaller than that on a silicon substrate at the same ion beam power The sub-100 nm patterns on a diamond were made under the charge neutralization mode to prevent charge accumulation. We successfully made a two-dimensional, 240 nm-width text of the 300-lettered Lord's Prayer on a gem diamond with 30 kV-30 pA FIB. The patterned text image was readable with a scanning electron microscope. Moreover, three dimensional nano-thick plate module fabrication was made successfully with an FIB and a platinum deposition, and electron energy loss spectrum (EELS) analysis was easily performed with the prepared nano plate module.

• Journal of the Korea Safety Management & Science
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• v.17 no.2
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• pp.55-66
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• 2015

In the perspective of industrial health management, it is important for the employee to decrease their job stress, to improve their productivity and quality of labor. In this study, the job stress, and it's influence on PWI(Psychosocial Wellbeing Index) were investigated by the questionnaire survey of 138 industrial workers who had studied assistive technology in college. The contents of questionnaire consist of the demographic characteristics, job-related characteristics, job stress and psycho-social stress. We evaluated job stress by KOSS-SF(Korean Occupational Stress Scale-Sort Form) and psychosocial stress by PWI-SF(Psychosocial Well-being Index-Short Form). To analyze the results, we evaluated the exposure level of KOSS and PWI by demographic characteristics and job-related characteristics using significance tests. Also, we estimated the relationship among demographic characteristics, job-related characteristics, job stress and psychosocial stress, using correlation analysis. As a results, all workers were found to be in a group under the high risky stress. It showed that the scale index of female's job non-autonomy and pwi were much larger than those of male's. Therefore, to guarantee job autonomy of female workers should be more emphasized, to improve their working environment. Job type had significant relationships with many job stress category; physical environment, job demand, job instability and organization culture. Regarding pwi, the scale index of the workers who is in charge of the civil service such as contacting the disabled and the aged in person, were much larger than that of the other workers. Accordingly, the job stress management program including physical environment, job demand, job instability and organization culture, should be suggested, to decrease the stress of the workers in charge of the disabled and the elders service. The strongest predictors of pwi was organization system through maximum positive relations between organization system and pwi. Therefore, it indicates that improvement of organization system such as a fair merit rating, a manpower supply, demand plan and department cooperation is urgently needed to reduce pwi.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.461-467
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• 2020

Industrial consultation is a kind of personal service for companies. The Industry-Academic Cooperation Foundation sets up a consultation contract in which a professor performs the consultation as the person in charge. Recently, there is an issue regarding taxation of the consulting fee paid to the professor; in short, there is no standardized practice for the imposition of income tax. In this study, we examine the characteristics of industrial consultation and present an acceptable taxation rule based on related laws. First, it is not appropriate to regard consulting fees as wage income, considering that there is no employment relationship between the Industry-Academic Cooperation Foundation and the professor. Considering that the base consulting fee amount is the same as the invention compensation, according to accounting practices, and that an employee invention is apt to be derived in the consultation, it is reasonable that the consulting fee should be regarded as wage income similar to employee invention compensation. As treating the consulting fee as wage income could end up reducing industrial consultations, the government should amend the income tax law to include industrial consultation as a type of other income.

• Korean Journal of Social Welfare
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• v.66 no.2
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• pp.287-317
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• 2014

The study conducts a comparative study of the supporting systems and methods of social enterprises in Korea, Japan, and Hong Kong to propose a policy on sustainable growth of social enterprises and their long-term activation. By investigating previous studies, this researcher drew the frame of a comparative analysis and conducted the comparative analysis. First, regarding the supporting system for social enterprises, it was found that Korea had better institutional foundation and system, whereas Japan had better activation, cooperation and network of intermediary support organizations. In Korea there is the law related to social enterprises, and the government takes control of all of the organization in charge of the policy, intermediary support organizations, cooperation and network, and authentication system. However, Hong Kong has yet to establish a basic institutional system to grow and activate social enterprises, and foreign intermediary supporting organizations increase the network and cooperation level to support social enterprises. Thirdly, for supporting methods for social enterprises, there were direct financial support, indirect business support and other kinds of support in Korea, whereas indirect support was activated in Japan. Although The Hong Kong government barely supports social enterprises, it comes up with a plan to support the firms serving as social enterprises under its the 12th 5-year development plan. For sustainable growth of Korean social enterprises, this study suggested the change of the government policy to the direction of creating social enterprise ecosystem through cooperation and network activation, indirect support in the middle of process, and activation of intermediary support organizations.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.1
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• pp.21-26
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• 2014

When iodine container for dental mouth treatment is opened, thread for treatment is cut by the blade in cap of container. Due to the problem of corrosion in a short period time after the reaction of metal blade to iodine solution, it gives impact on patient hygiene. In order to solve the problem, alternative products such as ceramic blade are developed and produced recently. In case of ceramic blade, it is produced by handwork and machine work. In this study, for the quantity production of ceramic blade with powder injection molding, we proposed a delivery system to have uniform charge of 20 cavity. Using Moldflow, simulation on 20 Cavity flow was performed. And then the mold was obtained through mold production and modification.(based on simulation) After injection molding, debinder, sintering process was achieved for ceramic blade, and the cap product was completed via insert injection on ceramic blade. In this study, we verified possibility of quantity production of ceramic blade which showed effective performance for cutting.

• Journal of Technologic Dentistry
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• v.13 no.1
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• pp.53-59
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• 1991

This study aimed at inquiring into the basic theory on CIEO(the Cooperation between Industry and Educational Organizations), grasping and analyzing the present situation of the health junior college, the present condition of CIEO and into problem and seeking to find a solution to activate the CIEO of the health junior colleges. This study suggested five methods as the method of consolidating the on-the-spot-training as below : 1. The execution of the basic research for the on-the-spot-training. And the reorganization of the existing curriculum into the curriculum the industrial organization requires. 2. The participation in solving commonly the problems of the industrial organization and in education. The establishing of the guidance system assuming exclusive charge of the on-the-spot-training. 3. The extension of the period of the on-the-spot-training and the reorganization of an educational system. The submission of the evaluation sheet for the on-the-spot-training. 4. The securing of the educational dost spent on the on-the-spot-training and the imposition of benefits on the industrial organization. 5. The persistent support for the on-the-spot-training at the governmental dimension. It is required that the CIEO law should be enacted as the legal and institutional solution and that government should lend systematic support to the business enterprise exeuting the industrial educational cooperation such as the institutional support for and the imposition of benifits on the cost of research. The cost of research and development, the cost of internal education and training, and the cost of experiment and practice.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.595-601
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• 2020

During the safety inspection of nitrocellulose-made explosive containers stored for more than 10 years, cracks were found in the containers. Therefore, a failure cause analysis test was performed. First, the cause of failure through the failure tree analysis was conducted to select the factors that influenced failure. The changes in the properties of the container caused by the acceleration of the reaction were found to be the cause of the failure by confirming the influence on the environment and internal/external factors that may occur during storage. To confirm this, environmental tests, such as thermal shock test and vacuum thermal stability test, were performed using a naturally aged container to analyze the cause of failure, and an accelerated aging test was performed to reproduce the failure. Through this, the chemical reaction was accelerated by heat and charge, as in the result of the fault tree analysis, and it was confirmed that the physical properties of the container were changed. In addition, the service life of the container was estimated using the Arrhenius model for the storage life due to thermal aging.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.8
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• pp.127-136
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• 2018

In daycare centers, the head teacher requires the leadership to effectively meet the demands of nursery facilities, since he or she plays a role of middle management in charge of communication with the director and the teachers. Therefore, this study aimed to investigate the structural relationship between the head teacher's leadership and job satisfaction of childcare teachers to enhance their organizational commitment and improve service quality and operation of nursery facilities. A survey was conducted of childcare teachers in national and public daycare centers located in Gyunggi Province from February to March 2018. Statistical analysis was performed using SPSS 23.0 and AMOS 23.0 statistical programs. Analysis results found that leadership of the head teacher positively affected job satisfaction and organizational commitment of childcare teachers. Second, the job satisfaction of childcare teachers positively affected organizational commitment. Third, job satisfaction of childcare teachers had a mediating effect in the relationship between the head teacher's leadership and the childcare teachers' organizational commitment. Results of this study suggest that effective leadership of the head teacher should be exercised to enhance the organizational commitment of childcare teachers.