• Journal of the Korean Geotechnical Society
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• v.39 no.11
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• pp.23-31
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• 2023

The escalating settlements observed in concrete slab tracks pose a significant challenge in Korea, raising concerns about their adverse impact on the safe operation of high-speed railways and the substantial costs involved in restoration. A primary contributor to these settlements is identified as the utilization of rock materials sourced from tunnel construction, incorporated into the lower subgrade without the requisite soil mixing to achieve an appropriate particle size distribution. This study employs numerical analysis to evaluate the efficacy of partial reinforcement in reducing settlements in rock-filled lower subgrades. Column-shaped reinforcement areas strategically positioned at regular intervals in the lower subgrade induce soil arching in the upper subgrade, leading to a concentration of soil loads on the reinforced areas and consequent settlement reduction. The analysis employs finite element methods to investigate the influence of the size, stiffness, and spacing of the reinforced areas on settlement reduction in the lower subgrade. The numerical results guide the formulation of an optimal design approach, proposing a method to determine the minimum spacing required for reinforcements to effectively limit settlements within acceptable bounds. This research contributes valuable insights into addressing the challenges associated with settlement in concrete slab tracks, offering a basis for informed decision-making in railway infrastructure management.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.6
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• pp.871-879
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• 2009

The Korea has high population density, so the precipitation per capita is only one tenth to world average. The water resource in Korea is insufficient. But the leakage in the water distribution system is about 25%, and it is lower than other countries where water utilities are managed well. The pipelines' management also is getting worse because the leakage in the pipelines lower the ground density surrounding pipes. So, managing the leakage in the water distribution system is very important in the view of increasing the water resources and doing the efficient management of the pipeline system. Accordingly this study aimed to conduct a cause-analysis with scientific approaches considering key local factor related to water loss of distribution system and derive better performance indicators which are able to evaluate the real state of water loss management reasonably. Also this research aimed to develop a methodology capable of judging condition of infrastructure of water distribution system.

• Asian Journal of Business Environment
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• v.10 no.2
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• pp.33-41
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• 2020

Purpose: This study assesses the marketing practices and value-added fish products under the Coral Reef Rehabilitation and Management Program (COREMAP) in East Indonesia. Research design, data and methodology: This study gathered qualitative and quantitative data through i) focus group discussions (FGD) with fishers, traders and COREMAP officers, ii) surveys and iii) interviews with fishermen and traders. This study surveyed 714 households (365 in COREMAP and 349 in non-COREMAP) and 33 traders (17 in COREMAP and 16 in non-COREMAP) using structured questionnaires between January and March 2016. This study used Shepherd's Index to estimate the marketing efficiency for each stage of the marketing channel. For value-added fish products, the value is determined by the difference between processed output and the raw product used. Results: Marketing cost in the non-COREMAP area was more efficient than in COREMAP as indicated by lower operational cost and higher selling price. However, no value-added fish products were produced in the non-COREMAP area. This study noted a lower catch in COREMAP area, which implies COREMAP program successfully reduced fishing pressure. Conclusions: This study identified poor infrastructure and the limited market as the major problems in developing value-added fish products in both COREMAP and non-COREMAP area.

• International journal of advanced smart convergence
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• v.7 no.2
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• pp.119-126
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• 2018

This study analyzed the digital divide of Korean senior citizens through the preference for smart media. Targeting two media out of mobile internet and mobile social media, the media dependency ratio and the trend of people in their 20s-60s were verified. Regarding the dependency ratio of young people(20s) and senior citizens(60s), in case of mobile internet, people in their 60s were average 8.6% while people in their 20s were average 38.9%, so that the ratio of senior citizens was lower by 30.3%. In case of social media, people in their 60s were average 1%, which was 7.1% lower than people in their 20s(8.1%). And this divide was the digital divide shown in the informatization process through the trend of internet use of senior citizens in their 60s or up. Thus, as the policy measures for solving the digital divide of senior citizens, it would be required to continuously develop the digital cultural programs for senior citizens, to expansively perform the government subsidiary policies like additionally providing the essential information to senior citizens, and also to expand the smart-based infrastructure for senior citizens' participation in economic activities.

• Journal of Acupuncture Research
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• v.40 no.3
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• pp.177-187
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• 2023

Varicose veins have a substantial burden on individuals' aesthetics and overall quality of life. The current body of research on Korean medical interventions for varicose veins is limited in Korea, and exploration into clinical trends is lacking. This review specifically analyzed fire acupuncture, which is an understudied intervention in Korea that demonstrated efficacy in alleviating pain and paralysis while promoting tissue regeneration. A comprehensive investigation of the China National Knowledge Infrastructure database was conducted, utilizing terms such as "varicose vein," "fire needle," "fire acupuncture," "burning acupuncture," "burning needle," "huǒzhēn," "xiàzhī jìngmài," and "jìngmài qūzhāng." This review included 14 studies investigating the role of fire acupuncture in treating varicose veins. We extracted variables, including age, sex, disease duration, intervention method, treatment frequency, treatment period, acupoints, and outcomes. Fire acupuncture appeared as the primary intervention method, followed by general acupuncture. The protruding part of varicose veins is the main treatment area for fire acupuncture, while the acupoints BL57 and ST36 were most frequently utilized for general acupuncture. Treatment results revealed significant improvement in all studies. However, there are limitations, such as scarce studies, limited side effects studies, and potential bias. Consequently, extensive and well-structured future studies are necessary to demonstrate the role of fire acupuncture in varicose veins.

• Proceedings of the IEEK Conference
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• 2000.06a
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• pp.49-52
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• 2000

The Multi-Code CDMA systems that are proposed as an effective transmission methodology in the IMT-2000 systems allow higher rate services under the IS-95 CDMA infrastructure. The Multi-Code CDMA systems convert the higher rate data into the lower rate by serial to parallel operation and spread the converted data streams by the multiple walsh codes, and its mobile receiver needs multiple walsh generators and data correlators to demodulate simultaneously multiple walsh code channels. Therefore, the number of data correlators is increased as the number of traffic channels increases. In this paper, we proposed the new structure of the data correlators using walsh overlay coding, the shared accumulator, and FWHT(Fast Walsh Hadamard Transform) algorithm for reducing the bottle-neck effect resulting the increase of the number of data correlators.

• Korean Journal of Computational Design and Engineering
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• v.16 no.1
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• pp.31-40
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• 2011

Product-service system (PSS) is a system of products and service, supporting networks and infrastructure that is designed to be competitive. PSSs satisfy customers' needs more effectively and have a lower environmental impact than traditional business models. Therefore, many companies and governmental institutes are eager to implement the PSSs as a new business model. In this paper, we focus on industrial practices as new business models for the company. PSS, especially, is popular in electronic industry, so one can often observe such examples as iPod, iPhone, e-Book and etc in the field. We first thoroughly investigate the current practices of PSS in Korean electronic industry. The examples are surveyed and projected directions are given. Then, non-electronic PSSs are surveyed. Especially mechanical PSSs are intensively discussed. Based on the survey results, we propose several major development strategies of Sustainable PSS (SPSS). SPSS will bring a competitive edge for company as realization of sustainable development of PSS considering economy, society, and environment.

• Korean Journal of Child Studies
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• v.30 no.6
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• pp.139-151
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• 2009

This study aimed to explore the current status of playgrounds, children's libraries and youth centers as local community centers in support of children. Its data were collected from reviewing the relevant literature, interviews, surveys and web search. It was found that children's libraries were predominantly located in Seoul and Kyungki provinces. In comparison with other advanced countries, Korea had lower ratios of volumes of books and periodicals per the library user and of a number of staff per the user. It was also found that over a half number of playgrounds was placed in apartment areas. Since 1993, the long-term youth development plan has commenced the construction of various societal infrastructure such as local youth centers, counseling institutes, sex-culture centers and youth cultural zones. Based on these findings, some policy issues were raised.

• Journal of the Korean Home Economics Association
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• v.42 no.2
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• pp.177-193
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• 2004

Using data from the 2001 Computer and Internet Use Survey by the National Statistical Office, this study investigated digital divide among women aged between 20 and 55. Following were the major findings. first, two-thirds of women did not use Internet even though many of these had Internet access at home. Second, those who did not have Internet access at home, those with a lower level of educational attainment, those with blue color or service occupations, and those with higher age were less likely to use Internet than their counterparts in these socio-economic variables. Third, expanding Internet infrastructure would not improve Internet use of the Elderly. Forth, the majority of those who did not use Internet did not recognize the Internet itself. Based on the result the policy implications for digital divide were suggested.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1175_1176
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• 2009

In comparison with different mass transportation systems, the streetcar is lower, both in speed and transportation capacity. However, it has the advantage of reducing the cost of construction, because it makes infrastructure simple, by using the road. It is proper in the city, where the population is few, to raise the efficiency of traffic. The convenience is high to passengers. On time accuracy and the commercial speed is influenced by operating condition. Generally that is organized into 21m degree in 6 quantity. All passengers in a streetcar are about 180 people. The maximum speed is 40~60km/h. When road traffic is considered, the speed can be reduced to 15km/h. To enhance the speed, the construction of a priority signaling system is necessary which is integrated with the road traffic operation information system. In order to develop a better Traffic Control System which is connected to a Traffic Control Center, a Priority Signaling System which incorporates Intersection Control Technics must be included.