• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.7
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• pp.3165-3174
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• 2012

Recently the increasingly common large refrigerator is the side by side(SBS) refrigerator whose freezing chamber and refrigerating chamber are set side by side. But one of the biggest dissatisfaction of customers about SBS refrigerator is that the two doors don't meet the same height when they are closed. It is called door height difference(DHD). The main cause of DHD is the unevenness of floor on which a refrigerator is placed or the cabinet deformation caused by long time use. When the DHD is confirmed, the customer or maintenance personnel use wrench to adjust the support screw to make the refrigerator to reach the horizontal position. But for big refrigerator, it is not only difficult for women and old people who don't have enough force to adjust it, but also inappropriate to require customers to do this job. In order to resolve this problem, this research proposes a new mechanism which can detect the DHD and adjust two doors to the same height automatically. The adjustment would be completed during opening and closing the doors, avoid needing hard operation with wrench by hand.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.12
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• pp.5839-5848
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• 2012

The demands for specially trained hemodialysis nurses are increasing as the population requiring maintenance hemodialysis expands. However, there has been no standardized training program for hemodialysis nurses in South Korea. The study was conducted to develop and evaluate a hemodialysis nurse educational program (HNEP). The effects of education using the HNEP were assessed by levels of hemodialysis-specific knowledge, self-efficacy and satisfaction. A total of 25 registered nurses participated in the HNEP which consists of 20 week education (classroom theory for 10 weeks and clinical practice for 10 weeks) between April and September, 2011. Knowledge levels were compared before and after the HNEP using paired t-test. Self-efficacy and satisfaction levels were also evaluated after the program using a scale of 1-5, 5 being the highest and 1 being the lowest. Knowledge levels were significantly increased after the HNEP (Mean=13.96 vs. 17.80, t=-7.748, p=<.001). Self-efficacy and satisfaction levels with the program were high, $3.90{\pm}0.42$ and $4.02{\pm}0.77$, respectively. These findings suggest that the HNEP improved hemodialysis-specific knowledge, and levels of self-efficacy and satisfaction with the HNEP were reasonably, among the participants.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.12
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• pp.6447-6454
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• 2013

Seawater intake systems have significant problems due to seawater pollution, suspended solids, unstable intake and maintenance etc. An underground type seawater intake system was newly developed to overcome the existing weaknesses and was facilitated in Gyukpo port. In this study, to check the performance of the new system, the samples for water quality and the 3-D numerical modeling test were conducted. The five times test included the COD, total nitrogen, total phosphorus, pH, and suspended solid for the intake system. The analyses show that the COD, total nitrogen, total phosphorus, PH showedminor changes before and after. On the other hand, the change in suspended solids was significant and water was purified below 5 mg/l, first level fisheries water, after. The numerical model adopted the RNG $k-{\epsilon}$ algorithm and the CFX model based on the finite volume method. The porosity algorithm was used to reproduce filtered-sand, outer diameter, and thickness. The numerical results showed that the double pipe is advantageous in that it provides a uniform pressure between the inner and outer pipe for the flow to be stable. In addition, the use of multiple intake pipes did not interfere with the discharge reduction of 0.98 at the both intake pipes compared with the central intake pipe.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.688-695
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• 2017

This paper deals with characteristics analysis of a permanent magnet (PM) linear generator using analytical methods for wave energy harvesting. The wave energy is carried out from the movement of a yo-yo system. A linear generator using permanent magnets to generate a magnetic force itself does not require a separate power supply and has the advantage of simple maintenance. In addition to the use of a rare earth, a permanent magnet having a high-energy density can be miniaturized and lightweight, and can obtain high energy-conversion efficiency. We derived magnetic field solutions produced by the permanent magnet and armature reaction based on 2D polar coordinates and magnetic vector potential. Induced voltage is obtained via arbitrary sinusoidal input. In addition, electrical parameters are obtained, such as back-EMF constant, resistance, and self- and mutual-winding inductances. The space harmonic method used in this paper is confirmed by comparing it with finite element method (FEM) results. These facilitate the characterization of the PM-type linear generator and provide a basis for comparative studies, design optimization, and machine dynamic modeling.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.8
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• pp.407-416
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• 2020

North Korea's demand for infrastructure construction and maintenance is growing rapidly. On the other hand, the number of skilled workers is insufficient. Therefore, through a survey of North Korean defectors, this study analyzed the status of construction technology and the difficulties of construction workers. In addition, an attempt was made to derive an appropriate education and training program process and operation plan. As a result of the survey, the reason for the low technical level of construction workers was the lack of skills, lack of motivation to work, and the lack of training and management systems. The appropriate education and training period was 56% of the total response within one year and 36% within six months. Based on the results of this survey, the period of education and training for the rapid training of construction technical personnel in North Korea was adopted as one year. Moreover, compared to the NCS standard in South Korea, appropriate training hours were suggested, excluding training courses, such as planning and design, construction management that require specialized knowledge. Finally, the curriculum corresponding to the education and training courses and the standards for facility names and required areas for facility operation were suggested.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.8
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• pp.154-159
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• 2020

In this study, we set the occupational satisfaction and communication ability of clinical dental hygienists as the main variables, and investigated the factors that affect communication within the organization to improve the work of dental hygienists. Self-reporting questionnaires were administered to 200 dental hygienists working in dental hospitals and dental clinics in Seoul and Gyeonggi Province from May 18, 2019 to June 12, 2019. We analyzed the data with Pearson correlation analysis and multiple regression analysis. The significance level was set at 0.05. Research results: Job satisfaction (r=0.193, p<0.05) and communication ability (r=0.404, p<.001) showed a significant positive correlation with intra-organizational communication, and individual communication ability (β=0.461, P<.001), which was found to have a significant effect on communication within this organization. Therefore, in order to improve the communication skills of dental hygienists, they should be proud of their work as professionals, enhance their job satisfaction, and be able to have a clear expression of their own intentions and effective dialogue. Efforts should be made to provide opportunities such as opening related lectures during internal education and maintenance education.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.2
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• pp.403-413
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• 2007

KREN(Korean Education Network), supported by government fur 20 years, had been operated and connected to many educational institutions from elementary schools to universities. From 2001, This network has been operated by a commercial network consignment organization and started to offer superb infrastructures to access various educational information conveniently. This network contributes development of Korean Information technology and promotes solidarity among educational institutions as well. Despite this achievement, KREN's effectiveness is not well recognized. Therefore, performance analysis study was carried out on KREN's achievement to verify its effectiveness, this study was to justify government's continuous support and also to find effective. This study was to justify government's continuous support and also to find effective ways of operations and maintenance fur the next step of KREN. Over 100 organizations were surveyed for performance analysis and we analyzed its results and anticipated effectiveness in this study. Cost, contribution, quality and performance were examined fur satisfaction analysis and each institution's number of students, network experiences were used as independent variables fer regression analysis to figure out effectiveness of the network. This study's result provides much information for further research which will help in the development of educational policies and maximizing KREN's effectiveness.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.7
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• pp.720-725
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• 2016

This study examined how the APU noise of an aircraft influences the work efficiency and stress of airport ramp workers. A survey of airport ramp workers was conducted and the results analyzed. In the demographic analysis, men outnumbered women - accounting for 86% of the survey target - and 80% of the respondents were found to be employees with less than 15 years of work experience. The occupational cluster of the total of 160 respondents included 41 aircraft maintenance workers, 70 ground staff (Cargo, Water and Waste services), 19 ramp coordinators, 18 ramp controllers and 12 catering Service workers. The ground staff were the most prevalent, constituting 44% of the occupational cluster. Regarding the APU noise, 74% of the respondents answered that the environment was "always noisy", while 26% answered that it was "sometimes noisy". 85% answered that they are sensitive to and put under stress by the APU noise, while the majority of the respondents answered that the APU noise degrades their work efficiency. In conclusion, this study examined the effect of APU noise on the work efficiency and stress of airport ramp workers by analyzing the survey data by Regression and Chi-square analysis.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.10
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• pp.4893-4901
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• 2013

In order for a machine, especially used in the defense industry, to consistently operate during its life-time, lots of study has been done in machine design as well as machine maintenance. However, the realistic study is necessary in management and operation of a military support facility, where spare parts are stored and retrieved. In this paper, efficient arrangement of spare parts are proposed to acquire increased in efficiency and decreased in cost for operation management of the military support facility. First, spare parts is assorted by MTBF(Mean Time Between Failure) and divided in to three groups A/B/C as an alternative arrangement. Each defined alternatives will go under simulations and RULA(Rapid Upper Limb Assessment), which is posture classification scheme evaluation attributes, to find working time and posture difficulty and lastly by entropy measurement to be selected. This research proposes the efficient spare parts arrangement in military support facility to minimize working time and posture difficulty. By taking system and human engineering approach together into consideration, it will lead to show a specific value.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.716-723
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• 2016

A computerized information management system of road bridges as a national key infrastructure is needed to effectively collect data of the current status, improve the reliability of data, and use the results from the analysis of the accumulated data as fundamental resources for supporting the establishment of policies. The Internet-based Bridge Information System (BIS), including a database and geographic information systems (GIS), was designed, and the data items were comprised of essential information, such as GIS-based location coordinates, bridge condition grade information and so on. The BIS was developed to be connected with a related information system, and it is possible to make the current information of traffic volume, address and so on by adopting the GIS. To enhance the reliability of the information of current bridge status, it is also possible to improve the accuracy of data through an information verifying function to prevent entry errors. In addition, the BIS can easily support the establishment of policies offering various types of knowledge information that were available in the past based on an analysis of the accumulated data. The intuitive identification and analysis of the current status is to be feasible through a GIS screen. Improvement of the business efficiency and data accuracy and time-series information analysis are available by managing the information of current status through BIS. In the future, it is expected that BIS can be used effectively for the establishment of reasonable maintenance policies of the nation.