• Journal of the Korean Society of Systems Engineering
• /
• v.18 no.1
• /
• pp.1-13
• /
• 2022

The Yongin Light Rail train was manufactured by Bombardier Transportation in Canada in 2008 and is a privately invested railway line that has been operating in Yongin-si, Gyeonggi-do, since 2013. When the frequency of train failure increases due to aging, and there is a delay in the delivery period of imported parts used in the Bombardier manufactured trains, timely vehicle maintenance may not be performed due to lack of parts. To solve this problem, it is necessary to build a 'vehicle parts maintenance demand forecasting system' that analyzes the accurate and actual maintenance demand annual based on the condition of vehicle parts. The full scope of analysis in this paper analyzes failure data from various angles after opening of Yongin light rail vehicle to analyze failure patterns for each part and identify replacement cycles according to possible failures and consumption of parts. Based on this study, it is expected that Yongin Light Rail's maintenance system will change from the existing time-based replacement (TBM) concept to the condition-based maintenance (CBM) concept. It is expected that this study will improve the efficiency of the Yongin Light Rail maintenance system and increase vehicle availability. This paper is a fundamental for establishing of a system for predicting the replacement timing of vehicle parts for Yongin Light Rail. It reports the results of data analysis on some vehicle parts.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.58 no.4
• /
• pp.289-298
• /
• 2022

Sea anchor for fishery is commonly used in jigging fishery and purse seine. The study of sea anchor was studied for improvement of opening efficiency and drag by changing the type of shape and the diameter of vent. However, standard specification of sea anchor is not set and has not been studied for underwater stability. Therefore, this study aimed to improve underwater stability of sea anchor by changing a vent diameter and weight of sinker. The experiment was conducted in flume water tank. The experiment model of sea anchor was made from actual model of sea anchor which is used in fishery by similarity law. The model of sea anchor was designed to different types of vent diameter and weight of sinker in different current speed. The value of movement of side to side (X-axis), drag of sea anchor (Y-axis) and movement of up and down (Z-axis) was measured for 30 seconds. Each value of X, Y, Z-axis was analyzed through t-test and ANOVA analysis to verify that each value had a significant difference according to the difference compositions. There was correlation between the movement of X-axis and Z-axis. The drag of sea anchor was stronger as the current speed increased. However, the larger the vent diameter, the weaker the drag. From the result of the standard deviation, the movement of X-axis was inversely proportional to the vent diameter. However, movement of Z-axis was larger as the weight of sinker was the heaviest or lightest from the result of the standard deviation. These results suggest that the sea anchor should be combined with proper size of the vent diameter and the weight of sinker to improve the stability.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2022.10a
• /
• pp.577-579
• /
• 2022

It is not easy to achieve the essential goal of knowledge management, which is to strengthen individual competence and organizational competitiveness, only by collecting distributed knowledge in the centralized knowledge repository conducted so far. In order to establish a sustainable knowledge ecosystem, we must expand knowledge production through exchange and cooperation, not independent knowledge production. Through this, producing meaningful and high-value knowledge resources becomes possible. Therefore, this study aims to design an integrated service platform that stores science and technology knowledge resources and reproduces and evolves knowledge through opening, sharing, and utilization. In order to evaluate its excellence, Five experts evaluated the designed platform on detailed items classified into planning adequacy, platform effectiveness, platform efficiency, and roadmap adequacy. The evaluation score averaged 95.56 points for the above four evaluation items.

• Journal of the Korean BIBLIA Society for library and Information Science
• /
• v.34 no.4
• /
• pp.55-75
• /
• 2023

This study proposes the establishment of a joint preservation library in the Chungcheongbuk-do region. It aims to transfer low-utilization materials from various libraries in Chungcheongbuk-do to the joint preservation library, thereby improving the efficiency of existing spaces and actively supporting the educational curriculum of school libraries. To achieve this, the study conducted document analysis, a status survey, and case analysis. The research results indicate that a reasonable standard for the accommodating capacity of the preservation library space is calculated at 280 volumes per square meter. Specifically, an initial transfer of 45,580 volumes for public libraries and 121,894 volumes for school libraries is proposed, totaling 167,474 volumes. Depending on the saturation levels of Chungcheongbuk-do Office of Education-affiliated public libraries and school libraries, the initial volume is determined to be 167,477 volumes, with an annual increase of 10% calculated over 30 to 50 years after the library's opening.

• Journal of the Korean Society for Library and Information Science
• /
• v.40 no.1
• /
• pp.335-351
• /
• 2006

For a library to be run more efficiently, its internal strengths and weaknesses, external opportunities and threats must be determined for forecasting on the basis of the diagnosis of the internal and external environment and situations, and optimum strategies and measures responsively deducted and utilized. Therefore, I had analyzed the strategic competition of university A's library using SWOT analysis, which has recently been spotlighted as an effective strategic competition analysis method. The conclusions thus obtained are as explained below. Firstly. the strengths of university A's library are the professional qualifications of the employees. work efficiency based on systematic operative plans and division of work load, and provision of high quality service following the establishment of the digital library. Secondly, its weaknesses are the insufficiency and limits of the usable resources, the lack of progressive future operation plans and systems, and the deficiency of a positive service mind. Thirdly, the opportunities are the possibility for new developments in accordance with the digital information environment. reinforcement of the operative efficiency throughout expanding its cooperation with external organizations and other libraries, and its transformation as the local library hub by opening up to the public. Fourthly, the threats are the lack of the school authorities' acknowledgement. and the degradation of the library's status in accordance, the users' various requests for information and advanced professional service according to the rapidly changing information environment. and the restriction of the library service based on the copyright law. Fifthly, as a result of analyzing the strategic competition of university A's library, measures such as the reinforcement of digital service by acquiring digital specialists. provision of extended service through active cooperation with external institutes and libraries. development and provision of differentiated service in accordance with the reinforced copyright law were proposed to improve the library's future competitiveness.

• International Journal of Highway Engineering
• /
• v.13 no.4
• /
• pp.51-59
• /
• 2011

Tensile stress occurs and random crack develops in concrete pavement slab when it contracts by variation of temperature and humidity. The tensile stress decreases and the random crack is minimized by sawcutting the slab and inducing the crack with regular spacing. The random crack, joint damage, decrease of load transfer efficiency are caused by too wide joint spacing while too narrow joint spacing leads to increase of construction cost and decrease of comfort. A mechanistic-empirical joint spacing design method for the concrete pavement was developed in this study. Structurally and environmentally weakest sections were found among the sections showing good performance, and design strengths were determined by finite element analysis on the sections. The joint width for which the load transfer efficiency is suddenly lowered was determined as allowable joint with referring to existing research results. The maximum joint spacing for which the maximum tensile stress calculated by the finite element analysis did not exceed the design strength were found. And the maximum joint width expected by the maximum joint spacing were compared to the allowable joint width. The new method developed in this study was applied to two zones of Hamyang-Woolsan Expressway being designed. The same joint spacing as a test section constructed by 8.0m of joint spacing wider than usual was calculated by the design method. Very low cracking measured at 6 years after opening of the test section verified the design method developed in this study.

• Korea Science and Art Forum
• /
• v.19
• /
• pp.405-415
• /
• 2015

Recently the development of China has attracted all over the world, many scholars of different areas are interested in Chinese Culture and Chinese Market. After sixties of last century development of the economic of the South Korea closer to modernization, but there are many problems, one of them is the urban living style boasts of the features of concentration. Because of this phenomenon the lack of housing space become more serious. It also come to be a social problems. Therefore narrow residential area become inevitability. At the same time, effective utilization of housing space become a demand. Especially for those families with limited living space, it's meaningful for them. Between the China and the South Korea. Chinese have the same situation too, the different is kitchen space of chinese is closed. It means they have to cook in limited space. With increased supplies and more small appliances, an inevitable requirement is opening out the kitchen space, but unreasonable furnishings and living space reduces the efficiency of the kitchen, which has led to the discontent of users. From this, base on the investigation and analysis of diet&living space of most chinese apartment, and through differences kinds and places of storage items. With them I would combine the food culture and feature of storage space of China to solve problems of the efficiency of the kitchen.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.14 no.2
• /
• pp.63-68
• /
• 1978

A boat seine has been used as a major fishing gear for catching anchovy (Engraulis japonica) in the southern coastal waters of Korea since the 1920s. Since the 1950s some improvement from the original seine has been made; powered boats equipped with net hauler has been used instead of rowing boats with hand-driven capstan, and the seining method has been changed into the trawling method. But even now, there are many problems to be solved in the view point of decreasing man power without decreasing catching efficiency. For the purpose, patti-net has been introduced from Japan and experimented on the commercial base since 1972, and it was known that the patti-net could be operated with man power as half as needed in the coventional net, but catching efficiency was not so desirable. Therefore, the study on the characteristics of it were required. The authors carried out a model experiment with a Qne-twentieth scale model net towed by a powered boat on the sea. The obtained results run as follows: 1. Hydrodynamic resistance of the model net can be explained as $R_p=69.6 V_{I.66}$ $R_h=37 v^2$ where $R_p$ and $R_b$ denote the resistance of the whole gear and the cod end in kg respectively, and v the towing speed in mlsec. 2. Performance of wing and cod end showed no deformation such as observed at the conventional net. 3. The ratio of opening at the entrance of bag net to that of cod end showed about 2: 1. Therefore, when we intend to enlarge the net to be able to operate in the deep fishing ground, the cod end should be enlarged in the same proportion and increased towing power is needed .. Then, it will be better to increase the ratio for increasing fishing efficiency without increasing towing power.

• Fire Science and Engineering
• /
• v.31 no.3
• /
• pp.79-87
• /
• 2017

Sandwich panels which are having the both sides are bonded with a heat insulating material with an iron plate are used as factories, warehouse structures as advantages of convenience in construction at economic efficiency of material cost. However, in a panel structure constructed by continuous joining of sandwich panels, a joint portion where a panel and a panel are connected is generated. The joint part is a part which is easily vulnerable to fire because flames easily flow into the melting and deformation of the iron plate during fire. The flames flowing into the panel induce diffusion of fire by rapid burning, causing damage of human life and property. In this research, we developed a flame spread prevention plate to prevent spreading of sandwich panel. This is an improvement of the workability by the anti-spreading construction method of the existing previous research, it can be applied independently to the connecting part where the panel and the panel are coupled, designed to prevent inflow and spreading of flame did. The actual fire test of the test method of KS F ISO 13784-1 of the sandwich panel specimen was conducted and the burning behavior corresponding to the presence or absence of application of the flame spread prevention plate was grasped at the panel connection part and its effect was measured. Inserting a fire spreading plate into the test result panel connecting part is measured by delaying the flashover, prevention of collapse of the specimen, and temperature rise of the opening, effectively improving the fire safety of the panel structure It was confirmed as a method that can be secured. It is judged that panel structure will contribute to ensuring fire safety by applying the fire spread prevention construction method of various methods ensuring the workability and economy of panel connection vulnerable to fire.

• KDI Journal of Economic Policy
• /
• v.14 no.3
• /
• pp.23-48
• /
• 1992

The Korea's Consumer electronics industry has exhibited a spectacular growth in the last three decades, expanding into one of the most important industries in Korea in many respects. One interesting aspect of the industry is the dominant role played by the Big Three of the industry, Gumsung, Samsung, and Daewoo. Since 1984, the three companies have accounted for about 90% of the sales in key items such as color TV, VTRs, refrigerators, and washers. The Big Three not only dominated the manufacturing stage, but also the distribution stage of the industry through their networks of exclusive dealers that constitute the major part of the distribution market. In this study, we analyzed the effects of the exclusive dealing by the Big Three on the efficiency of the Korean economy. We find that exclusive dealing by the Big Three could seriously constrain competition in both the manufacturing and distribution stages of the industry. Exclusive dealing by the Big Three effectively forcecloses the market for most other manufacturers as well as deterring entry into the manufacturing stage by potential entrants. Further, it impedes the growth of distributors that achieve the economies of scale and scope and restricts competition by the Big Three. In contrast, we could find little evidence that exclusive dealing by the Big Three is pro-competitive or enhances welfare. As a remedy to this problem, we suggest that the Fair Trade Commission of Korea should regulate the exclusive dealing by the Big Three, thus opening the door for the growth of distributors that are not bound by an exclusive dealing relationship with any of the Big Three. Put differently, we urge the Korean Fair Trade Commission to apply the Article 23 (5) to the exclusive dealing by the Big Three. Article 23 (5) that states that unfair restrictive dealing is illegal has never been clarified by the FTC. We believe that our analysis could also serve as a basic for the clarification of the article in general.