• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.11
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• pp.1055-1064
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• 2017

Since a device such as a rocket motor requires very high reliability, a reasonable reliability design process is essential. However, Korea has implemented a design method for applying a safety factor to each component. In classic reliability analysis, input variables such as mean and standard deviation, used in the limit state function, are treated as deterministic values. Because the mean and standard deviation are determined by a small amount of data, this approach could lead to inaccurate results. In this study, reliability analysis is performed for bolted joints and o-ring seals, and the Bayesian approach is used to statistically estimate the input variables. The estimated variables and failure probability, calculated by the reliability analysis, are derived in the form of probability distributions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.4987-4998
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• 2014

Recently, the use of nanotechnology in products is constantly expanding, and the problems on human health hazard has emerged as a major issue. A nanomaterials regulatory policy on the products is urgently required. This study analyzed the introduction of regulatory policies of nanomaterials contained in industrial products. In this study, the AHP (Analytic Hierarchy Process) method was applied and three regulatory policies were evaluated to analyze the validity of the introduction of a nanomaterials regulatory policy. To select the optimal regulatory policy, the policy evaluation criteria were set as enforcement (effectiveness), economics, acceptability, and protection. For the regulatory policies, self-regulation, product labelling, and enforced registration were introduced and evaluated as the regulatory policies, and product labelling was selected as the optimal regulatory policy.

• Convergence Security Journal
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• v.10 no.4
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• pp.31-37
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• 2010

The risks and threats in IT security systems to protect, prevent damage and Risk should be minimized. Context of information security products such as information processing, storage, delivery, and in the process of information system security standards, That is the basic confidentiality, availability, integrity and secondary clarity, potential evidence, detection, warning and defense capabilities, to ensure sufficient and should be. Web services are the most important elements in the security, the web nature of port 80 for the service to keep the door open as a structure, Web applications, web sources and servers, networks, and to hold all the elements are fundamental weaknesses. Accordingly, these elements through a set of Web application development errors and set-up errors and vulnerabilities in Web applications using their own home pages and web servers to prevent hacking and to improve the efficiency of Web services is proposed methodology performs security BMT.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.1
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• pp.125-132
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• 2011

Fire monitoring system detects a fire based on the values of various sensors, such as smoke, CO, temperature, or change of temperature. It detects a fire by comparing sensed values with predefined threshold values for each sensor. However, to prevent a fire it is required to predict a situation which has a possibility of fire occurrence. In this work, we propose a fire recognition system using a fuzzy inference method. The rule base is constructed as a combination of fuzzy variables derived from various sensed values. In addition, in order to solve generalization and formalization problems of rule base construction from expert knowledge, we analyze features of fire patterns. The constructed rule base results in an improvement of the recognition accuracy. A fire possibility is predicted as one of 3 levels(normal, caution, danger). The training data of each level is converted to fuzzy rules by FCM(fuzzy C-means clustering) and those rules are used in the inference engine. The performance of the proposed approach is evaluated by using forest fire data from the UCI repository.

• Journal of the Earthquake Engineering Society of Korea
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• v.11 no.3 s.55
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• pp.43-52
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• 2007

This study suggests a method to determine optimal seismic retrofitting schemes for existing bridges based on weighting-factored evaluation. According to the recognition for potential seismic risk, various kinds of retrofitting methods are applied to improve the seismic performance of existing bridges. However, the relevant technique is not available to select optimal retrofitting scheme for bridges now. This suggested method weights five factors, structural compatibility, economic efficacy, environmental factor, consturctability and maintenance, and draws out optimal seismic retrofitting schemes. The application of the developed method to one hundred sixty existing bridges verifies the adaptability of this method. As a result, this study provides an idealized retrofitting schemes, and the suggested method could be a guideline to determine the more cost-effective and optimal retrofitting schemes for existing bridges in Korea.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.912-916
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• 2010

국내 통합수자원관리기술 수준은 계속되는 연구와 개발 노력으로 선진국 수준을 따라잡을 것으로 기대되나 개발된 기술의 실용성, 적용효과를 가시적으로 보여주지 못하고 있다. 따라서 본 연구에서는 통합수자원 관리 기술을 적용하고자 강원도 평창군의 평창강 유역을 대상으로 통합수자원관리 전략을 수립한다. 평창강 유역의 대부분이 평창군이라는 하나의 행정구역에 속해 있어 본 연구에서는 평창강 유역 단위로 자료의 수집이 어려운 부문은 평창군을 기준으로 수집하여 분석하였다. 이수, 치수, 환경, 조직 및 정책 부문으로 나누어 평창군의 수자원 현황을 파악하고 평창군 수자원관리의 강점, 약점, 기회, 위협 요인을 분석(SWOT 분석)하였다. 그 결과 평창군의 강점은 수자원에 대한 관심이 높고, 관련 문제를 해결하고자 하는 의지가 강하다는 것이다. 약점은 수자원관리를 위한 총괄조직이 없다는 것이고, 위협요인은 기후변화에 따른 국지성 집중 호우로 홍수피해 위험성이 증가하고 있다는 점이다. 반면, 평창군의 기회요인으로는 동계올림픽 유치를 위한 노력이 계속되고 있어 토지 및 수자원 개발 측면에서도 좋은 기회가 될 수 있다. SWOT 분석의 결과를 고려하여 통합수자원관리를 위한 전략을 제안하였다. 평창군 물문제 해결을 위한통합수자원관리 실행을 목표로 '평창물관리위원회' 설치를 제안하였다. 그리고 평창군의 통합수자원관리 기반을 조성하기 위해서는 이해당사자의 참여가 필요하며, 평창군 통합수자원관리지원시스템 구축을 제안하였다. 이러한 전략에 따라 강원도 평창군에서는 '평창군 물관리위원회 운영 조례(2009.9.11, 평창군 조례 제1919호)'가 제정되었고 평창군 물관리위원회를 이끌어갈 위원들의 구성도 마무리되었으며, 이를 지원할 평창군 통합수자원관리 지원 시스템도 구축되어 운영되고 있다. 앞으로의 계획은 2010년 4월 평창군 물관리위원회 창립총회를 시작으로 평창군 스스로 위원회를 운영하고 물관리 비전을 설정하고 실행계획을 수립할 수 있도록 지원할 계획이며;구축된 평창군 통합수자원관리지원시스템의 운영을 활성화하는 것이다. 이와 같은 통합수자원관리 적용 노력을 통합수자원관리 성공 사례로 발전시켜 나아가 국내는 물론 국외에서도 좋은 모델로 활용할 수 있을 것이다.

• Smart Media Journal
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• v.8 no.1
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• pp.9-18
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• 2019

In the era of the 4th industrial revolution, the big data industry is gathering attention for new business models in the public and private sectors by utilizing various information collected through the internet and mobile. However, although the big data integration and analysis are performed with de-identification techniques, there is still a risk that personal privacy can be exposed. Recently, there are many studies to invent effective methods to maintain the value of data without disclosing personal information. In this paper, a personal information protection system is investigated to boost big data utilization in industrial sectors, such as healthcare and agriculture. The criteria for evaluating the de-identification adequacy of personal information and the protection scope of personal information should be differently applied for each industry. In the field of personal sensitive information-oriented healthcare sector, the minimum value of k-anonymity should be set to 5 or more, which is the average value of other industrial sectors. In agricultural sector, it suggests the inclusion of companion dogs or farmland information as sensitive information. Also, it is desirable to apply the demonstration steps to each region-specific industry.

• The Journal of the Korea Contents Association
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• v.22 no.5
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• pp.1-15
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• 2022

In this study, text analysis was performed on the mealkit product review data to identify factors affecting the evaluation of the mealkit product. The data used for the analysis were collected by scraping 334,498 reviews of mealkit products in Naver shopping site. After preprocessing the text data, wordclouds and sentiment analyses based on word frequency and normalized TF-IDF were performed. Logistic regression model was applied to predict the polarity of reviews on mealkit products. From the logistic regression models derived for each product category, the main factors that caused positive and negative emotions were identified. As a result, it was verified that text analysis can be a useful tool that provides a basis for maximizing positive factors for a specific category, menu, and material and removing negative risk factors when developing a mealkit product.

• 한국벤처창업학회:학술대회논문집
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• 2021.04a
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• pp.49-53
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• 2021

'양손잡이 조직(Organizational Ambidexterity)'은 새로운 기회를 찾고 위험을 감수하며, 신제품이나 신사업을 개발해 가는 탐색(Exploration) 역량과, 최소한의 리스크와 보유한 자원을 토대로 기존 제품이나 서비스를 중심으로 효율성을 높이는 활용(Exploitation)적 혁신을 동시에 추구하는 조직의 능력으로 경영자들이 비즈니스 환경의 난기류와 다차원성에 대처하도록 권고하는 개념들 중 하나이다. 본 연구는 스타트업의 양손잡이 역량 균형이 기업 성과에 미치는 영향에 대한 연구를 기반으로 양손잡이 역량이 실제 스타트업에 긍정적으로 영향을 미치는 지를 조사하는데 목적으로 하고 있다. 따라서 탐색(Exploration)과 활용(Exploitation)의 적절한 균형(Balance)을 중심으로 기업성과에 미치는 영향과 더불어 환경적 동태성(Environmental Dynamics)의 조절효과에 대하여 알아보고 분석하였다. 실제로 선행 연구를 통해 탐색(Exploration)과 활용(Exploitation)에 모두 관여하는 양손잡이 기업들이 하나에 집중하는 기업보다 우수한 성과를 달성할 가능성이 높은 것으로 나타났으며, 탐색(Exploration)과 활용(Exploitation)의 적절한 균형(Balance)을 유지하는 것이 생존과 번영을 위해 중요한 것으로 나타났다. 특히, 자원이 부족한 스타트업의 경우 부족한 자원을 효과적으로 활용하고 양방향으로 행동할 수 있는 능력은 경영 능력과 역량에 달려 있기 때문에 지속적인 생존을 위해 탐색과 활용의 균형을 맞추고 효과적인 조직을 구축해 양손잡이 조직으로 거듭나야만 한다. 양손잡이 조직에 대한 연구 이론은 보통 여유 자원이 높은 대기업을 기준으로 정의되고 있으며, 상대적으로 여유 자원의 수준이 낮은 중소기업이나 스타트업을 위한 양손잡이 조직의 의미와 이러한 기업들이 추구할 수 있는 현실적인 실행방안에 대해서는 연구가 부족한 실정이다. 따라서, 본 연구는 실제 스타트업 기업의 성장을 위한 전략적 방향 설정을 제시할 수 있으며, 급격하게 변화하는 시장에서 스타트업의 양손잡이 역량과 기업성과 영향 관계를 분석하여 학술적인 기여를 할 수 있을 것으로 기대한다.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.4
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• pp.317-325
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• 2015

An adequate downscaling of synoptic forecasts is a prerequisite for improved agrometeorological service to rural areas in South Korea where complex terrains and small farms are common. In this study, geospatial schemes based on topoclimatology were used to scale down the Korea Meteorological Administration (KMA) temperature forecasts to the local scale (~30 m) across a rural catchment. Then, using these schemes, local temperatures were estimated at 14 validation sites at 0600 and 1500 LST in 2013/2014 and were compared with the observations. The estimation errors were substantially reduced for both 0600 and 1500 LST temperatures when compared against the uncorrected KMA products. The improvement was most notable at low lying locations for the 0600 temperature and at the locations on west- and south-facing slopes for the 1500 LST temperature. Using the downscaled real-time temperature data, a pilot service has started to provide the field-specific weather information tailored to meet the requirements of small-scale farms. For example, the service system makes a daily outlook on the phenology of crop species grown in a given field using the field-specific temperature data. When the temperature forecast is given for next morning, a frost risk index is calculated according to a known relationship of phenology and frost injury. If the calculated index is higher than a pre-defined threshold, a warning is issued and delivered to the grower's cellular phone with relevant countermeasures to help protect crops against frost damage.