• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.710-719
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• 2017

This study conducted a survey on the time serial change in the aging ratio and population structure in new towns and their housing complex of Korea and Japan, and revealed the differences in the factors that affect the aging ratio in new towns of Korea and Japan through a comparison of the housing provision of housing complex with a high aging ratio. Rapid aging is underway around the housing complexes that were developed in the beginning of Tama new town in Japan. Agingtends to increase in proportion to the opening time of the housing complex. Rental housing residents of early migration households showed rapid aging because they had generation separation early due to narrow housing. On the other hand, Bundang new town maintains a lower aging ratio and speed than Seoul and Seoul metropolitan area due to the constant influx of student population. On the other hand, aging is more likely to increase in large houses due to the depression of the real estate market.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1999.04a
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• pp.22-22
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• 1999

교란에 대한 고체 추진제의 연소율의 반등에 대한 이해는 고성능 추진제를 설계하는데 매우 중요한 요소이다. 그 동안의 연구는 고체 추진제의 표면에서 발생하는 교란이 매우 작은 크기로 발생한다는 선형적인 가정을 사용하여 이론적인 응답 함수를 구하였다. 특히 실험실에서 행해지는 교란에 대한 추진제의 응답 함수를 구하기 위하여 이용한 비집촉식 교란 방법을 사용하였다. 이 경우 추진제 표면으로 전달되는 복사열 전달의 크기는 레이저에 의한 복사 일전달과 기체 영의 화염에 의한 열전달을 동시에 고려하여야 한다. 그러나 언급하였던 것처럼 대부분의 이론적 연구는 추진제 표면의 온도 구매가 단열인 것으로 가정하여 진행하였다. 이러한 가정을 기체 영역으로부터 추진제로 전달되는 열전달 량이 작은 점소화초기 등에서 타당한 가정이나, 기체 영역에서 연소가 활발하게 진행되는 경우에는 비합리적인 가정이다. 본 연구에서는. 추진제의 응축 영역에서 분포 화학 반응이 발생하여, 기체 영역에서 화학반응에 의한 연소가 진행되는 경우, 복사 열전달의 교란에 대한 추진제의 응답함수를 수치적으로 계산하였다. 이때 기체 영역에서 발생하는 연소 반응은 De Luca 등에 의하여 제안된 실험적 모델인 $\alpha$ $\beta$ ${\gamma}$ 화염 모델을 사용하였으며, 추진제 표면에서의 열전달 균형에 의한 경계 조건을 사용하였다. 그러나 외부로부터 입사되는 복사광 레이저와 기체 영역의 상호 간섭은 고려하지 않았다. 수치 계산에 의한 응답 함수의 특징은 단열 조건이 사용된 이론적 응답 함수에 비하여 낮은 값을 나타내었으며, 최대치를 보이는 주파수 영역도 이론 함수에 비하여 다른 값을 보여주고 있다.연구 분석 결과 기술적 문제점으로는 배기 가스온도가 낮은데 따른 출구 부분의 Bearing, Sealing이 문제가 될 수 있다고 판단되며 배기 가스 자체에 대기 공기중에 함유되어 있던 습기가 얼어붙는(Icing화) 문제가 발생하기 때문에 배기가스의 Icing을 방지하기 위하여 압축기 끝단에서 공기를 추출하여 배기부분에 송출할 필요성이 있는 것으로 판단되었다. 출구가스의 기체 유동속도가 매우 빠르므로 (100-l10m.sec) 이를 완화하기 위한 디퓨저의 설계가 요구된다고 판단된다. 또 연소기 후방에 물을 주입하는 경우 열교환기 및 기타 부분품에 발생할 수 있는 부식 및 열교환 효율 저하도 간과할 수 없는 문제로 파악되었다. 이러한 기술적 문제가 적절히 해결되는 경우 비활성 가스 제너레이터는 민수용으로는 대형 빌딩, 산림, 유조선 등의 화재에 매우 적절히 사용되어 질 수 있을 뿐 아니라 군사적으로도 군사작전 중 및 공군 기지의 화재 그리고 지하벙커에 설치되어 있는 고급 첨단 군사 장비 등의 화재 뿐 아니라 대간첩작전 등에 효과적으로 활용될 수 있을 것으로 판단된다.가 작으며, 본 연소관에 충전된 RDX/AP계 추진제의 경우 추진제의 습기투과에 의한 추진제 물성 변화는 미미한 것으로 나타났다.의 향상으로, 음성개선에 효과적이라고 사료되었으며, 이 방법이 편측 성대마비 환자의 효과적인 음성개선의 치료방법의 하나로 응용될 수 있으리라 생각된다..7%), 혈액투석, 식도부분절제술 및 위루술·위회장문합술을 시행한 경우가 각 1례(2.9%)씩이었다. 13) 심각한 합병증은 9례(26.5%)에서 보였는데 그중 식도협착증이 6례(17.6%), 급성신부전증 1례(2.9%), 종격동기흉과 폐염이 병발한 경우와 폐염이 각 1례(2.9%)였다. 14

• Journal of Bio-Environment Control
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• v.30 no.4
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• pp.410-418
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• 2021

This study was conducted in 8.2m wide single-span greenhouse to investigate the effect of presence or absence of rafter steel pipe joint and foundation conditions on greenhouse structural performance. Structural performance was evaluated by static loading test using the structural performance evaluation system for single-span greenhouse. The measured displacement was compared with the predicted result by numerical analysis. The displacement of each measurement location showed a significant difference regardless of the conditions of the foundation and presence or absence of rafter steel pipe joint. Compared to the hinge conditions, the difference in structural performance of the greenhouse in the fixed conditions was seen to be relatively large. The difference in structural performance according to presence or absence of rafter steel pipe joints, the lateral stiffness of the joint was 8.1% greater.

• Journal of Korea Port Economic Association
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• v.37 no.2
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• pp.91-105
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• 2021

The current increasing size of container vessels affects the container port's situation. The containerization has changed the inter-modal handling process, which brought more flexibility and comfortableness in the shipping industry sector. Thus, it is very crucial to analyze the efficiency of container ports in the regional sphere. Such kind of efficiency analysis provide a powerful management tool for port operators and shipping managers in the Mediterranean market, and it also helps to form an information for planning new regional and national port operations. This paper aims to analyze the ports' technical efficiency of Mediterranean major container ports. It is conducted to establish the model of port performance and efficiency through the empirical test of the various factors. Regarding to the panel data collected from the 48 DMUs (decision making units), this study attempts to provide the empirical basis of the port efficiency relative to another factors in the total port performance. Due to the complexity of the various activities carried out at container ports, the study focuses only on the technical efficiency at the level of the Mediterranean container port. Unlike the practice of cross-sectional data analysis, originally established by Charnes et al. (1985), the panel data in DEA window analysis applications are used. The main focus of this study is the relative technical efficiency of 12 container ports from 7 countries in the Mediterranean market. The selection of ports under study is based on their high handling capability and rankings in World Top 100 (Containerization International, 2018).

• Journal of the Korean GEO-environmental Society
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• v.20 no.2
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• pp.69-79
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• 2019

The coastal area forms various sedimentary layers according to the environmental conditions such as the topography and geological features of the upper region of the river, ocean currents, and river mouth. Therefore, identifying the characteristics of the marine clay deposited in the coastal area plays a key role in the investigation of the formation of soft ground. In general, alluvial grounds are formed by a variety of factors such as changes in topography and natural environment, they have very diverse qualities depending on the deposited region or sedimentation conditions. The most important thing for the construction of social infrastructures in soft ground areas is economical and efficient treatment of soft ground. In this study, the author collected data from diverse laboratory and field tests on five areas in western and southern offshore with relatively high reliability, and then statistically analyzed them, thereby presenting standard constants for construction design. Correlation between design parameters such as over consolidation ratio, preconsolidation pressure was analyzed using linear and non-linear regression analyses. Also, proposed distribution characteristics of design parameters in consideration of each region's uncertainty through statistical analyses such as normality verification, outlier removal.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.5
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• pp.170-179
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• 2019

Following the uprise of the Korean Wave, Korean big entertainment corporations, such as SM or YG, are selling cultural products through their subsidiaries. These cultural products or 'cultural goods' are using artists' images of the entertainments for various products including stationary, consumer electronics, cosmetics, snacks, etc, to produce significant profits. We focused on the level of marketing strategy that affects the intention of purchase of those cultural goods. Specifically, we classified three levels including product-level(quality and design), brand-level(price and brand name), and corporate-level(merchandising and sales methods) and investigated if consumer nationality has any effects on the relationship. Based on the survey results performed by 220 Korean and Chinese college students, we found that Chinese consumers generally have higher intention to purchase on Korean cultural goods. Especially, Chinese consumers showed that their purchase intention is affected by price and brand name strategies, thus we found that they are more sensitive to brand-level marketing strategies.

• Tunnel and Underground Space
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• v.31 no.1
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• pp.10-24
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• 2021

Rock mass classification for construction of underground facilities is essential to secure their stabilities. Therefore, the reliable values for rock mass classification from the precise information on rock discontinuities are most important factors, because rock mass discontinuities can affect exclusively on the physical and mechanical properties of rock mass. The conventional classification operation for rock mass has been usually performed by hand mapping. However, there have been many issues for its precision and reliability; for instance, in large-scale survey area for regional geological survey, or rock mass classification operation by non-professional engineers. For these reasons, automated rock mass classification using LiDAR becomes popular for obtaining the quick and precise information. But there are several suggested algorithms for analyzing the rock mass discontinuities from point cloud data by LiDAR scanning, and it is known that the different algorithm gives usually different solution. Also, it is not simple to obtain the exact same value to hand mapping. In this paper, several discontinuity extract algorithms have been explained, and their processes for extracting rock mass discontinuities have been simulated for real rock bench. The application process for several algorithms is anticipated to be a good reference for future researches on extracting rock mass discontinuities from digital point cloud data by laser scanner, such as LiDAR.

• Food Science and Industry
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• v.53 no.2
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• pp.235-247
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• 2020

Current status of the domestic food industry and major issues are reviewed, and some problems derived from the R&D aspect are analyzed. Particularly, the role of the public sector and the direction of R&D are presented in order to enhance the vitality of the food industry and strengthen the competitiveness of small and medium-sized businesses. At first, the government needs to provide a consistent R&D roadmap through macroscopic coordination, and public institutes and private companies should come up with practical and concrete collaborative measures. It is also necessary to set the investment direction for food R&D in the public sector, taking into account the strategic importance of core technology and the global level difference, targeting on basic research and public platform technology. More efforts to discover agendas focused on food technology and link them to large-scale R&D projects are urgently needed to solve national and social problems through food research.

• The Southeast Asian review
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• v.28 no.1
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• pp.145-171
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• 2018

Laos' 2017 is a year of political "stagnation" and economic "change". In the political arena, despite the achievements such as the improvement of the corruption perception index (CPI), it is necessary to watch the progress of the reform. Diplomatically, the influence of China is expected to increase further. In particular, since November 2017, Xi Jinping's visit to Laos is expected to strengthen the framework of cooperation between the economic corridor and Lanchang-Mekong Cooperation Meeting. And Laos continued to have friendly relations with other neighboring countries, the ASEAN countries. However, the issue of the Laos-Cambodian border issue following the general election in Cambodia may recur. The economic sector maintained a high growth rate due to capital inflows from the construction of large infrastructures and the favorable tourism industry, but structural problems such as deficits in the fiscal and current account should be resolved. Korea and Laos discussed the comprehensive cooperation between the two countries through the Mekong Senior Officials' Meeting in March 2017 and the Ministerial Meeting of the Korean-Lao Foreign Minister in September 2017. Laos is Korea's eighth ODA aid (grant), and ODA will become an important diplomatic cooperation channel between the two countries in the future. In the economic relationship, the trade sector is on a declining trend, but investment and human exchanges are steadily increasing.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.1
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• pp.88-96
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• 2021

When oil tankers, large passenger ships and cargo ships sink under the sea owing to various maritime accidents, the residual cargo oil or fuel oil in the such vessels could pose direct risk to factor for the marine environment and it require safe and rapid removal. Although domestic and foreign salvage companies are adopting various recovery methods and technologies with customizations according to each site during recovery operations studies on reasonable assessment modules for the operation process are relatively insufficient. In this study, the data from trapped-oil recovery operations performed at different site conditions were collected and analyzed in order to designed an operation assessment module, define the operational process steps in terms of preparation, implementation and completion, and derive key factors for each detailed process. Subsequently, the module was designed in such a way as to construct performance indicators to assess these key factors. In order to exclude subjective opinions from the assessment as much as possible, the assessment each item was constructed with indicators based on data that could be evaluated quantitatively and its usefulness was verified by applying the module to the trapped-oil recovery operation cases. We expect this the method and the technology assessment module for the trapped-oil recovery operation on sunken vessels will help to verify the adequacy of the trapped-oil recovery such operation before or after. Furthermore, it is expected that the continuous accumulation of assessment data and feedback from past or future operation cases will contribute toward enhancing the overall safety, efficiency and field applicability of trapped-oil recovery operation.