• Title/Summary/Keyword: 한시성

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A Numerical Analysis on the Thermal Protection System Applied Phase Change Material (상변화물질을 이용한 열방어체계의 수치해석 연구)

  • Oh, Chang-Mook;Yoo, Yung-Joon;Min, Seong-Ki
    • Journal of the Korean Society of Propulsion Engineers
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    • v.16 no.4
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    • pp.80-86
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    • 2012
  • This study is for figuring out a possibility of realization of the thermal protection system(TPS) for temporary use under high temperature condition and improving a design of the future TPS. On this purpose, environmental condition of the system has been simplified: the boundary conditions consist of a internally heating surface and a externally heated surface which is simulating the external high temperature condition. Configuration of the system is simplified as a hexahedon. Melting characteristics of the phase change material(PCM) and air temperature variation of TPS with or without connector have been numerically analyzed and compared. As a result of numerical analysis, the heat from the internally heated surface could not be effectively transferred. Therefore, temperature of inner space has been increased.

The Pattern of Labor Migration in Ansan and Their Local-Social Relationship (안산지역 이주노동자의 노동이주 유형과 지역-사회관계)

  • Lee, Taejeong
    • Korean Journal of Labor Studies
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    • v.24 no.3
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    • pp.73-107
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    • 2018
  • The purpose of this study is to shed light on the characteristics of the social relations of migrant workers in the Ansan area and the factors for the construction of those characteristics. The social relations of migrant workers in the Ansan area are affected by the Korean government's policy of EPS, a short-term rotation policy and its ban on the settlement of migrant workers. These workers are likely to form a temporary and bounded social relationship. The bounded social relationship of migrant workers to society is one of the major factors that put them in social poverty. Ethnic communities, support organizations for migrant workers, and local government agencies have assumed the task of helping build the network among migrant workers of various ethnic backgrounds as well as aiding their participation in local social activities. The status of a temporary resident is the prime reason for spatial exclusion and social poverty among migrant workers. To prevent the exacerbation of these phenomena, this study suggests that the government reconsider its short-term work permit policy for less skilled workers.

Correlation Analysis between COVID-19 and Plastic Emissions: Upcycle (코로나19와 플라스틱 배출량과의 상관관계 분석: 업사이클)

  • Lee, Ji-Hyeon;Hwang, Seung-Yeon;Kim, Jeong-Joon
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.22 no.5
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    • pp.165-170
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    • 2022
  • The amount of data generated by recent developments in Big data and related technologies has been rapidly increasing, and the need to predict changes in future societies and present technologies to be realized has been continuously raised to lay the foundation for national scientific and technological planning. The existing methods of predicting future technologies have their respective advantages, but problems also exist. Thus, this paper newly establishes and applies the methodology to be used for predicting future technologies specialized in information security fields beyond the existing comprehensive prediction, and draws out innovative technologies that are expected to have high ripple effects in the future, and analyzes the technological diffusion points of each technology to predict future technological changes in the information security sector. It is expected that this will ensure reliability and objectivity of the forecast survey results and allow more sophisticated and multilayered predictions than the overall scientific and technological forecast surveys.

A Study on the Consumption Patterns of Poor Households (빈곤계층의 소비패턴에 관한 연구 : 2007년과 2008년의 변화 비교)

  • Joung, Won Oh;Lee, Sun Jeong
    • Korean Journal of Social Welfare Studies
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    • v.42 no.1
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    • pp.305-331
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    • 2011
  • This study analyzes the consumption patterns of the poor households. The first objective of this analysis is to show that the group living in poverty get not one consumption pattern but several types of consumption patterns. The second objective is to understand what factors effect the consumption patterns. This study use the data of Korea Welfare Panel Study in 2008 & 2009. In oder to achieve first goal, We conduct factor analysis and cluster analysis. And to achieve second goal, We conduct multinomial logistic Analysis. Major findings are as follows. First we find six patterns of consuming types of the poor households. They are education oriented consuming type, diet oriented type, social network oriented type, transportation-communication oriented type, health & medical oriented type, and housing expenditure oriented type. Second we find these consumption patterns are effected by not economic factors but socio-populational factors, especially by life cycle of members of household.

Token-Based User Dynamic Access Control for Secure Device Commands in Smart Home (스마트 홈에서 안전한 디바이스 제어 명령을 위한 토큰 기반 사용자 동적 접근제어 기법)

  • Hyeseon Yu;Minhye Seo
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.34 no.4
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    • pp.553-568
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    • 2024
  • Due to the rapid development of IoT technology and the increase in home activities after the COVID-19 pandemic, users' demand for smart homes has increased significantly. As the size of the smart home market increases every year and the number of users increases, the importance of personal information protection and various security issues is also growing. It often grants temporary users smart home owner rights and gives them access to the system. However, this can easily allow access to third parties because the authorities granted are not properly managed. In addition, it is necessary to prevent the possibility of secondary damage using personal information collected through smart home devices and sensors. Therefore, in this paper, to prevent indiscriminate access to smart home systems without reducing user convenience, access rights are subdivided and designed according to the functions and types of smart home devices, and a token-based user access control technique using personal devices is proposed.

The Effect of Employment Security on Suicide Ideation: Moderating Effect of Family Function (고용안정성이 자살생각에 미치는 영향: 가족기능의 조절효과 분석)

  • Jun, So Dam;Lee, Jin Hyuk;Song, In Han
    • The Journal of the Korea Contents Association
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    • v.20 no.4
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    • pp.553-563
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    • 2020
  • Suicide is one of the major social problems in Korea, and its suicide rate is highest among the OECD countries. It has been reported that employment instability in labour market is causal factor of suicide ideation. Because the unemployed and temporary or part-time workers are reported to have high level of suicide ideation due to unstable job security, and they are likely to be a high risk group for suicide, it is necessary to do in-depth research on the effect of job stability on suicide ideation and the protective factors. For this purpose this study investigates the relationship between employment status and suicide ideation, and examine the moderating effect of family function. Data of 1,235 adults from the national-wide 'Longitudinal Study of Suicide Survivors' Mental Health were analyzed. Employment status were associated with the level of suicide ideation(B=-.904, p<.001), and the level of suicide ideation was the highest in the unemployed group. And the moderating effect of family function was statistically significant(B=-.218, p<.05), and good family function buffers the effect of unstable job status on suicide as a protective factor. Based on these findings, policy and practical implications for suicide prevention for precarious employment from the family dimension are discussed.

A study on the Form of Sijo seen from Various Aspects (다각적 관점에서 본 시조 형식 연구)

  • Im, Jong-Chan
    • Sijohaknonchong
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    • v.30
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    • pp.147-164
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    • 2009
  • The conclusion of this paper is as follows. First, the authentic syllable count of sijo can be summed up as following: Second, the structure of the statement can be summed up as following: 1) Each statement extremely excludes the use of modifiers to clarify the development of the logic. 2) The meaning of each of the three statement, chojang (the 1st statement), jungjang (the middle statement) and jongjang (the last statement), is connected to the previous one closely, so the text as a whole is perfect. 3) The last statement identifies itself as the conversion or conclusion of the whole text. Therefore, the last statement should begin with a connective adverb like 'Therefore' or 'Then'. But in ancient sijo works, this sort of connected adverb is normally omitted. 4) Each statement of sijo is composed of one of the 4 structures suggested below: a) subjective phrase + predicative phrase b) the formal clause + the latter clause c) location-indicating phrase + sentence d) objective phrase + predicative phrase Since the text of a sijo work is formed like this, sijo is said to be composed of three jang (statement) & six gu (phrase), which is the very feature that proves that sijo is a fixed form of verse.

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Supporting Market Entry Decisions For Global Expansion Using Option +Scenario Planning Analysis (실물옵션 및 시나리오 분석을 활용한 해외 건설시장 진출 의사결정 지원모델의 개발)

  • Kim, Byung-Il;Kim, Du-Yon;Han, Seung-Heon
    • Korean Journal of Construction Engineering and Management
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    • v.10 no.5
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    • pp.135-147
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    • 2009
  • The world has witnessed the dramatic expansion of international construction markets during the last decades, particularly around the developing economies and energy resource-rich countries. However, despite the booming markets, the risks of emerging regions have also increased under the rapidly changing environments confronting the global contractors. Most of all, success in overseas business mainly depends on selecting the right market to enter. Accordingly, the right market selection requires global firms to carefully carry out the scientific market entry decision by evaluating country risks, market prospects, firm's capability, level of competition, and among others. This study aims at developing a market entry model by the use of real option analysis (ROA) and scenario planning, which addresses the corporate strategic flexibility against the uncertainties encompassing the overseas construction markets. Based on the suggested approach, global contractors are expected to make a better decision rather than a typically static approach in pursuing, postponing, or abandoning a prospective market to their capacity with a concurrent consideration of uncertainties as well as its option value.

Study on the Effectiveness of Korean Active Labour Market Polices (재정지원 일자리사업의 정책효과성 추정)

  • Chon, Joo-Yong;Jun, Jaesik
    • Journal of Labour Economics
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    • v.40 no.1
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    • pp.99-132
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    • 2017
  • This study examines the employability of participants and employment outcomes in the Korean active labor market policies(ALMPs). The data used in empirical testing is Korea Labor and Income Panel Study 1~15th survey data, participants database in ALMPs and Unemployment Insurance database. The main results are as follows. Level of employability in participants with ALMPs is about 56.3 and that of participants with direct job creation(DJC) programs shows the most low level in sub-type of ALMPs. About 30.8% of all people participating in ALMPs belongs to vulnerable group and 71.5% of participants in DJC programs is in vulnerable group. In DJC programs, the participants with low level of employability are some more likely to be in vulnerable group. As the level of employability in participants with DJC programs increases, their job-search time after moved in labor market reduces and their duration of employment increases. To summarize, one can imply that the DJC programs are effective to transit vulnerable groups in labour market and improve the labor market outcomes by enhancing the employability of participants.

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Clinical Results of Arthroscopic Salvage Repair including Popliteus Tendon as a Post for Complex Lateral Meniscus Tear (복합성 외측 반월상 연골판 파열에서 슬와건을 한시적 지주로 시행한 구제적 성격의 관절경 봉합술의 임상 결과)

  • Park, Sang-Eun;Kim, Sang-Kil
    • Journal of the Korean Arthroscopy Society
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    • v.14 no.1
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    • pp.1-6
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    • 2010
  • This study was undertaken to document the clinical results and technical aspects of arthroscopic repair including popliteus tendon as a post for the treatment of complex lateral meniscus in young people indicated as total meniscectomy. From June 2004 to May 2006, we prospectively studied arthroscopic repairs on 32 young people knees with symptomatic complex lateral meniscus that was treated by all inside repair technique using Popliteus tendon as a post. Clinical results were evaluated using Lysholm knee scores preoperatively and at final follow-up. 2nd look arthroscopy or MRI was taken at final follow-up. 80% of patients carried out MRI or 2nd look arthroscopy under permission. Most patients who follow up were able to return to their previous life activities with little or no limitation, and no reoperation was required after an average follow-up of 42.8 months. Mean Lysholm knee scores improved from 65.4 (range, 55 to 75) preoperatively to 93.9 (range, 79 to 100) at the final follow-up (P<.001). 80% meniscus healing was found on arthroscopic or MRI follow up. Conclusively, arthroscopic repair using Popliteus tendon as a post is effective for treating young people with complex lateral meniscus tear as a salvage procedure.

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