Special Theme 3 화재예방과 안전시스템 구축 - 노인요양시설의 화재안전 개선방안

최동수,Choe, Dong-Su 한국화재보험협회 2011 防災와 保險 Vol.142 No.-

주요국의 정보통신산업에 대한 규제완화정책 비교

최동수 한국경영교육학회 2012 경영교육연구 Vol.27 No.4

This study is intended to compare the competition principles and deregulation policy trends of major developed countries (USA, Japan, UK, Germany, France, New Zealand) in the information communication industry, and to determine future implications for Korea’s information communication policy based on such comparison. In major developed countries’ deregulation policies regarding the information communication industry, they have promoted, in common, market liberalization-centric restructuring such as a separation of regulatory agency from a general administrative body and operating agency, the information communication business’ privatization, a relief of conditions for new entries, a combination of broadcasting and information communication, a change into price ceiling and an inducement of foreign capital. On the other hand, as to the differences in major developed countries’ deregulation processes, the USA and UK have introduced and strengthened competition, New Zealand has promoted a universal removal of regulations, and Japan has an asymmetric regulation against NTT. Considering the aforementioned developed countries’ information communication environment, South Korea should promote the liberalization (privatization and marketization) by deregulation for growth of the information communication industry. As one of methods for responding to the global information communication environment, South Korean information communication carriers also should actively support such environment through a development of new business and partnerships and cooperation with developed countries in information communication, as well as technology development. The introduction of competition into the information communication system, a reform of information communication business structure and the formation of a fair competition environment among information communication carriers which have been promoted for an opening of the information communication market will seem to give rise to improving the competitiveness of the domestic information communication industry. 본 연구에서는 주요 선진국(미국, 일본, 영국, 독일, 프랑스, 뉴질랜드)의 정보통신시장에서의 경쟁원리의 도입과정과 규제완화 정책동향을 비교하고, 이를 토대로 우리나라의 정보통신정책에의 시사점을 모색하는데 그 목적이 있다. 먼저 주요 선진국의 정보통신산업 규제완화정책에 대한 공통점은 규제기관과 일반 행정기과 및 사업운영기관의 분리, 정보통신사업체의 민영화, 신규진입조건의 완화, 방송·정보통신의 융합, 가격상한제으로의 전환, 외자도입 등 시장의 자유화를 중심으로 구조조정을 추진하고 있다. 반면, 주요 선진국의 규제완화과정에서 나타난 차이점을 살펴보면 미국, 영국 등은 경쟁의 도입·강화, 뉴질랜드는 규제의 전면적 철폐, 일본은 NTT에 대한 비대칭적 규제를 하고 있다. 이러한 선진국의 정보통신환경을 고려해 볼 때 우리나라 역시 정보통신산업의 발전을 위해 규제완화에 의한 자유화(민영화 및 시장화)를 추진하고, 또한 세계의 정보통신환경에 대응하기 위한 방법의 일환으로 우리나라의 정보통신사업자는 기술개발뿐만 아니라 신규 사업의 전개 및 통신선진국과의 제휴와 협력관계를 통해 적극적으로 대처해 나가야 할 것이다. 그리고 정보통신시장의 개방에 대비하여 추진했던 정보통신사업경쟁체제도입, 정보통신사업구조 개편, 정보통신사업자간 공정경쟁 환경조성 등이 국내 정보통신사업의 경쟁력 강화라는 결실로 맺어지게 될 것이다.

F-5 전투기 에어컨 냉각터빈 손상원인 분석 및 향후 결함발생 방지를 위한 오리피스 설계

최동수,이영규,황진석,신보현 한국항공우주학회 2011 한국항공우주학회 학술발표회 논문집 Vol.2011 No.4

F-5 전투기에 사용하고 있는 에어컨 냉각터빈에 대한 손상분석과 향후 결함발생 방지를 위한 대책으로 오리피스를 설계하였다. 현재 공군에서 장기 운용중인 F-5 전투기는 신형과 구형의 두 가지 종류의 에어컨을 장착하여 사용 중에 있다. 이중 구형 에어컨의 냉각터빈은 신형보다 과다한 성능으로 터빈의 내구성이 저하되어 잦은 결함을 발생시킨다. 오리피스는 냉각터빈으로 유입되는 공기압력을 일정량 감소시키기 위한 목적으로 설계되었다. 오리피스 유량공식으로부터 압력차와 영구압력 손실량을 계산하였으며, 상용 전산유체 및 유한요소해석 프로그램을 사용하여 압력강하를 검증 및 구조재를 선정하였다. 또한 오리피스가 장착된 에어컨에 대한 성능은 지상 작동시험 및 비행시험을 통하여 입증하였다. Failure analysis on air-con. cooling turbine of F-5 fighter was performed, and orifice to prevent the further damage on that was also designed. Currently, F-5 fighters of R.O.K. Air Force have two kinds of air-con. packages, i.e. old type and new type. Between them, the old type has more defects than the new one because of the excessive performance of cooling turbine. The orifice was designed to reduce the air pressure which is entering the cooling turbine and it also lowers the speed of turbine rotor. The difference of pressure and the permanent pressure loss was calculated using orifice flow formula. The quantity of pressure loss was confirmed using commercial computational flow program and the material of orifice was selected through FEA. The performance of orifice was verified by ground flight test.

돼지고기 시장동향과 전망

최동수,Choe, Dong-Su 대한양돈협회 1999 養豚 Vol.21 No.5

천연가스의 안전과 가스 누설 감지 기술

최동수 한국가스학회 1997 가스산업과 기술 Vol.1 No.1

디지털시장의 시장구조와 제품판매방식

최동수 기술경영경제학회 2002 Journal of Technology Innovation Vol.10 No.2

Expansion and enhancement of information and communication infrastructure can create a market closer to an ideal type for a perfect competition, utilizing a cyber space in the network (with the expanded usage of Internet and e-commerce) and it could be a market of a monopolistic form. The government can take one of the two approaches responding to this monopolization of the digital market. First, the government maintains laissez-faire policy since the monopoly cannot be maintained over a long period of time due to an increasing in the production, decrease in the price, profit resulting from this and rapid technology evolution. Second, the government can actively interrupt the monopolization of the digital market. Monopolization in a digital market can lead to a market failure. Unstable market structure and too much frequent merger and acquisition contribute to making the digital market very dynamic. Information goods exchanged in the digital market have the features of very low marginal cost required to copy the original product whereas its initial fixed cost is very high. This explains why the information products are not priced based on the existing marginal price determination principles and why companies producing them have various product sales strategies (price/product differentiation strategy, and other sales strategies).

Static and Dynamic FEM Simulation of Packaging Tray Cup Pad for Korean Pears

최동수,손재영,김진세,김용훈,박천완,정현모,황성욱 한국포장학회 2019 한국포장학회지 Vol.25 No.3

Among the many packaging materials used in cushion packaging, there is a lack of optimum design for the tray cup pad used in fruit packaging for export and domestic distribution. It causes over-packaging due to excessive material input, and this could be solved by applying various parameters needed to optimize the design of the tray cup pad considering the packaging material and the quantity of fruits in the box. In the case of a tray cup for fruits, the economic efficiency of material and thickness should be considered. Therefore, it is possible to design a tray cup pad depending on the packaging material used by applying appropriate design parameters. The static and dynamic characteristics of the materials used for packaging of pears were analyzed by using the FEM (finite element Method) simulation technique to derive the optimal design parameters. And by applying the appropriate design parameters considering the quantity of fruit and distribution environment, it is possible to design an appropriate fruit tray cup pad. In this study, as a result of simulating the contact stresses between the fruit and the tray cup for the PP, PE, and PS materials used in the fruit tray cup, the material with the lowest contact stress was PP and the value was found to be 398 Pa. The contact displacement between fruit and tray cup using this material was about 0.0463 mm, which was the lowest value compared with other materials. Also the resonance frequency band of tray cup made of PP material was below 36.81 Hz, and the strain energy was below 12.20 J. The resonant frequency band of the pear is more than 80 Hz and it could be applied to all the tray cup materials as compared with the resonance band of 38.81 Hz or less which is the resonance band of all tray cup pads for packaging. Finally, PP is the most suitable material for the tray cup pad.

전투기 날개 수리를 위한 기계적 체결의 형상 선정에 관한 연구

최동수,Choi, Dongsu 한국군사과학기술학회 2021 한국군사과학기술학회지 Vol.24 No.5

A study on optimal shape selection of a mechanical fastening for the repair of crack defect of ROK Air Force F-5 fighter wing was conducted. The crack defect occurred in the spar of the wing, and the technical manual does not specify the repair method. However, ROK Air Force decided to develop a repair technology for this defect in consideration of various logistic conditions. Three repair shapes for the proper repair were devised and the finite element analysis was performed to examine the structural safety of these three connection members. As a result of the structural safety review, two connection members except one were structurally safe with safety margins over zero because the calculated stress values were at or below the yield strength level. Therefore, two connection members were determined to be able to use for repair under the condition that the aircraft operated within the design limit load. The results of this study would be very useful if the same defect occurs in long-term aircraft operated by the ROK Air Force.

PLA 트레이 포장 수출용 배의 수송 모의환경 진동 스트레스에 의한 품질변화

최동수,손재용,김진세,김용훈,박천완,황성욱,박종민,정현모,Choi, Dong-Soo,Son, Jae-Yong,Kim, Jin-Se,Kim, Yong-Hoon,Park, Chun-Wan,Hwang, Sung-Wook,Park, Jong-Min,Jung, Hyun-Mo 한국포장학회 2021 한국포장학회지 Vol.27 No.2

The characteristics of vibrational stress (shock and vibration) during transport and the possibility of damage to the packaged pears by functional PLA tray were investigated. And this study was conducted to analyze how environmental conditions by simulated transport environment affect quality factors such as weight loss (%) and soluble solid content (SSC, %), and firmness (bioyield strength, kPa) of packaged pears by PLA tray and Expanded PET foam pad (Group 1), EPE cushion cup pad and net (Group 2) for exporting. Pears with or without vibration stress were stored for 30 days at low temperatures (5 ± 0.8℃, 80 ± 5% relative humidity). There was the statistically significant difference (p ≤ 0.05) between pears with and without vibration stress for weight loss, soluble solid content, and firmness (bioyield strength) after 30 days storage. Vibration stress accelerated pear quality deterioration during storage, resulting in increased weight loss, soluble solids content, and reduced hardness. The firmness (bioyield strength) and weight changes of pears with PLA trays were smaller than those of conventional packaging box systems. It was determined that the firmness of agricultural products was a quality factor closely related to the storage period and that PLA could be applied.

국내 지육가격 변동에 따른 돼지고기의 수입가능성

최동수,Choe, Dong-Su 대한양돈협회 1996 養豚 Vol.18 No.3