• Journal of the Korean association of regional geographers
• /
• v.19 no.3
• /
• pp.416-435
• /
• 2013

Pyeongtaek port, opened in 1986, has played a role as an international trading port. Pyeongtaek city which is a hinterland with Pyeongtaek port has both landscape of city and rural area. Aims of this study is investigating the regional change of Pyeongtaek city according to the opening of Pyeongtaek port: the change in population and land value by the average distance(27.3km) between Pyeongtaek port and each region and the change in industry and regional industry with location quotient of region. The increasing rate of population and people who work for industry showed an aspect of rising as a place locates near Pyeongtaek port, yet the increasing rate of land value showed little differences. In short, as the area is closer to Pyeongtaek port, the number of population and employees are higher. Yet, the increasing rate of the land value showed little difference. The study showed that manufacturing industry is specialized in rural region(eup myeon region), and tertiary industry is specialized in urban region(dong region) of Pyeongtaek city according to location quotient.

• Journal of the Korean Regional Science Association
• /
• v.32 no.4
• /
• pp.51-73
• /
• 2016

Considering the intensified ties between Korean service industry and the other industries in China and Japan, this study empirically analyzes the inter-industry network between the service industry in the Korean capital region and 10 industrial sectors in 20 city-regions of China, Japan, and Korea(CJK). Firstly, unit structures are constructed based on the estimated CJK interregional input-output tables to understand the production connection. Moreover, the reorganized unit structures are visualized as networks and examined from various angles. As the results of the analysis, the inter-industry network of the service industry in the Seoul Metropolitan Area is still mostly dependent on domestic industries, especially on manufacturing industry, while it shows the tendency to be weakly connected to the industries in Chinese and Japanese city-regions.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.43 no.3
• /
• pp.101-111
• /
• 2020

Companies struggle to make their best products with high quality and service at a competitive price in global markets. However, customer needs and requirements keep changing with a variety of situations. Companies that face the changes can not stay the same and make an effort to adapt themselves to new circumstances. They would probably review the overall management system that is currently implementing to improve management efficiency. Among other things, quality might be considered to be a crucial element if they are manufacturing industries to be sustained in global markets. KSA (Korean Standards Association) is a government-affiliated organization under the Ministry of Trade, Infrastructure, and Energy. It is a Korean standards provider for quality and service industry. KSA confers national commendations for organizations, quality circles, artisans, QCEC (Quality Competitive Excellent Company), and the most honorable KNQA (Korean National Quality Award) every year. KSA established KNQA on the basis of Malcom Baldrige National Quality Award, Deming Prize, and European Quality Award. Research on quality awards shows that there are many similarities in the framework. Although KSA summarizes two factors for 13 evaluation indicators in the quality competitive excellent model of QCEC, the categorization is ambiguous to explain them according to earlier studies. We performed a deep analysis of foreign quality awards and background for KNQA and QCEC. We conducted a content analysis of KNQA and QCEC and matched evaluation items that were closely related. We proposed a quality competitiveness model with three factors, Technology, System, and Tools, summarizing 13 evaluation indicators in QCEC. Based on audit data for six years from 2012 to 2017 we carried out a confirmatory factor analysis for the proposed model by examining the model validity and fitness.

• Journal of the Korean Geographical Society
• /
• v.51 no.3
• /
• pp.381-399
• /
• 2016

Goesan-gun and Jeungpyeong-gun, Chungcheongbuk-Do have been separated administratively since 2003. Goesan-gun is rural area, and Jeungpyeong-gun is urban area. The purpose of this study is to observe changes after the separation of administrative districts (Goesan-gun and Jeungpyeong-gun, Chungcheongbuk-Do). This study observed changes of Goesan-gun and Jenugpyeong-gun, Chungcheongbuk-Do based on population, the highest land value, employees and location quotient. Population of Goesan-gun has decreased, and that of Jeungpyeong-gun has increased. The highest land value of Jeungpyeong-gun has increased more than that of Goesan-gun. Observation of location quotient, with the location quotient of 2013 as a criterion, showed that manufacturing business and producer service business have developed in Jeungpyeong-gun, while agriculture and customer service business have developed in Goesan-gun. This result is due to the difference between regional characteristic of Goesan-gun and Jeungpyeong-gun.

• Land and Housing Review
• /
• v.11 no.3
• /
• pp.11-19
• /
• 2020

This study aims to examine the relationship between the improvement of the income distribution index from the late 1980s to the 1990s and large-scale housing supply projects such as the 2 million housing construction project. Looking at Korea's economic development in terms of income growth and distribution, GDP has continuously increased since the establishment of the government, especially in the late 1980s. The Gini Index, a representative income inequality index, rapidly deteriorated in the early 1970s, and gradually improved from the late 1980s. The 2 million housing construction project, announced in 1988, supplied a third of the existing nationwide housing stock of 6.5 million units in three years. The project cost was 65 trillion won, equivalent to 50% of Korea's GDP at the time. This study questioned whether the ratio of the number of employed workers in the construction industry was a variable directly affecting the Gini Index. To verify this, the causal relationship between the proportion of employed workers in the construction and manufacturing industries and the Gini Index from 1979 to 2008 was statistically analyzed. For this, the ARIMA model was established for each variable, and the correlation of their residuals was verified. The 2 million housing construction project had the effect of improving income inequality in terms of rising wages for production workers and creating jobs for the low-educated and low-income class. During the project period, the number of middle-income earners increased sharply, and the income gap between the high-income and low-income earners greatly decreased. The expansion of the construction volume can be used as a powerful and direct policy tool for improving income distribution. However, the effect may be limited. When the proportion of workers exceeds the threshold, the effect is weakened.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.62 no.4
• /
• pp.181-185
• /
• 2013

This paper deals with the electromagnetic loss characteristics of enclosures for a 24kV high voltage switchgear by using a finite element method (FEM). A study on the electromagnetic characteristics of enclosures for a high voltage switchgear should be conducted to minimize the size and the temperature rising of a switchgear. Generally, the enclosures made by stainless steel are used to minimize the eddy current loss caused by the transporting current in Bus bars due to its non-magnetic characteristics although the price of stainless steel is expensive compared with other metal for enclosures. Therefore, a switchgear made by stainless steel enclosures could be fabricated as a small size and are applied to a switchgear in urban substations. On the contrary, the switchgear enclosures made by steel could be fabricated with relatively cheap manufacturing price. However, the temperature easily rises due to the transporting current in Bus bars because steel is a ferromagnetic material. Therefore, the size of a switchgear made by steel enclosures is relatively massive and installed in rural substations. In this paper, the electromagnetic losses in the enclosures of a switchgear according to various enclosure thicknesses are calculated and compared with each other. Especially, we proposed a hybrid type enclosures for a switchgear made by stainless steel (top and bottom enclosure) and steel (left and right enclosure). It is concluded that the cost electromagnetic performance of applying the hybrid type enclosure is favorable to develop a high voltage switchgear.

• Resources Recycling
• /
• v.25 no.1
• /
• pp.31-39
• /
• 2016

Small household appliances such as electric rice cooker, a vacuum cleaner, an electric fan, etc. are diverse and complex due to the materials and components and waste streams from the manufacturing processes. In the present study, physical characterization of small e-wastes was analyzed on major items including electric rice cooker after manual dismantling. Small household appliances is an important potential source of waste plastic, however, recycling plastics from small e-waste is still unusual. The present communication gives results of separation processes on black plastics and the limitations of these sorting processes in used small household appliances.

• Tunnel and Underground Space
• /
• v.29 no.1
• /
• pp.1-11
• /
• 2019

This study investigated use cases of machine learning technology in domestic medical, manufacturing, finance, automobile, urban sectors and those in overseas mining industry. Through a literature survey, it was found that the machine learning technology has been widely utilized for developing medical image information system, real-time monitoring and fault diagnosis system, security level of information system, autonomous vehicle and integrated city management system. Until now, the use cases have not found in the domestic mining industry, however, several overseas projects have found that introduce the machine learning technology to the mining industry for improving the productivity and safety of mineral exploration or mine development. In the future, the introduction of the machine learning technology to the mining industry is expected to spread gradually.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.1
• /
• pp.470-476
• /
• 2019

The braking force for a train is generally provided by compressed air. The pressure valve system that is used to apply appropriate braking forces to trains has a complex flow circuit. It is possible to make a channel shape that can increase the flow efficiency by 3D printing. There are restrictions on the flow shape design when using general machining. Therefore, in this study, the compressed air flow was analyzed in a pressure valve system by comparing flow paths made with conventional manufacturing methods and 3D printing. An analysis was done to examine the curvature magnitude of the flow path, the diameter of the flow path, the magnitude of the inlet and reservoir pressure, and the initial temperature of the compressed air when the flow direction changes. The minimization of pressure loss and the uniformity of the flow characteristics influenced the braking efficiency. The curvilinear flow path made through 3D printing was advantageous for improving the braking efficiency compared to the rectangular shape manufactured by general machining.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.12
• /
• pp.25-31
• /
• 2018

Selective Laser Melting is one of the representative 3D printing techniques for handling metal materials. The main factors influencing the characteristics of structures fabricated by the SLM method include the build-up angle of structures, laser power, laser scan speed, and scan spacing. In this study, the tensile properties of AlSi10Mg alloys were investigated by considering the build-up angle of tensile test specimens, laser scanning speed and scan spacing as variables. The yield stress, tensile strength, and elongation were considered as tensile properties. From the test results, it was confirmed that the yield stress values were lowered in the order of 0, 45, and 90 based on the manufacturing direction of the tensile specimen. The maximum yield stress value was obtained at 1870 mm / min based on the laser scan speed. The yield stress size decreased with decreasing scan speed. Based on the laser scan spacing, as the value increases, the yield stress increases, but the variation is smaller than the other test criteria. The tendency of the tensile strength and elongation variation depending on the test conditions was difficult to understand.