• Wind and Structures
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• 제21권6호
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• pp.597-607
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• 2015

With an increasing demand of a renewable energy, new offshore wind turbine farms are being planned in some parts of the world. Foundation installation asks a significant cost of the total budget of offshore wind turbine (OWT) projects. Hence, a cost reduction from foundation parts is a key element when a cost-efficient designing of OWT budget. Mono-piles have been largely used, accounting about 78% of existing OWT foundations, because they are considered as a most economical alternative with a relatively shallow-water, less than 30 m of seawater depth. OWT design standards such as IEC, GL, DNV, API, and Eurocode are being developed in a form of reliability based limit state design method. In this paper, reliability analysis using the response surface method (RSM) and numerical simulation technique for an OWT mono-pile foundation were performed to investigate the sensitivities of mono-pile design parameters, and to find practical implications of RSM reliability analysis.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 1998년도 Proceedings of International Workshop on Advanced Image Technology
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• pp.79-84
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• 1998

This paper describes implementation of the core DSM-CC UU interface. It briefly describes the reference model for the DSM-CC and related standards that should be reviewed for the implementation. The Common Object Request Broker Architechture, Revision 2.0 (CORBA 2.0) is sued as a remote procedure call (RPC) scheme for the UU Interface. Entire system was implemented with C++ on Windows NT platforms. The implementation procedure has been decomposed ito two tasks. The first task is to implement the Naming Service for service navigation. The Naming Service is one of the CORBA Services that extend the core CORBA specification. A client GUI is implemented for easy navigation among various services. The second task is to construct multimedia server and client for a Video-on-Demand (VoD) system. MPEG-2 Transport Stream is transported via ATM AAL5 using the Windows Socket 2.2 ATM extension API. A GUI enables the user to navigate the service domain and select a program. After the selection the user can control the MPEG-2 stream with VCR-like buttons.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 추계학술대회
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• pp.467-470
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• 2016

이 논문은 농업 비즈니스에서 농산물 생장/유통 환경에서의 센서 정보를 GS1 표준을 통해 운용하는 방법을 다룬다. 농산물 생장/유통 환경 모니터링을 위해 사용되는 센서들의 종류와, 이러한 센서 정보를 운용하기 위한 GS1 표준 식별자, 표준 이벤트의 구조, 생장/유통 환경정보를 저장/공유하는 스키마의 구조를 정의하며, 표준 인터페이스로 정보를 저장,공유 하는 방법을 설명한다.

• 대한의생명과학회지
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• 제29권4호
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• pp.256-262
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• 2023

The purpose of this study is to investigate microbial contamination in water purifiers from two universities (A and B) in Chungcheong region and to evaluate about the harmfulness of the isolated bacteria to the human. The degree of microbiological contamination of six water purifiers at university A was investigated three times from July 2018 to September 2019, and nine water purifiers at university B were investigated in 2023. The isolated bacteria were biochemically identified using an API kit and Vitek-2 system, and then the bacteria were identified to the species level using MALDI-TOF MS. In addition, the possibility of human infection of the isolated bacteria was evaluated through a literature search. In July 2018 and September 2019, the number of bacteria isolated inside the faucet was below the acceptable standard for hot water, but exceed for cold water in all water purifiers. In January and September 2019, bacteria exceeding the acceptable standards were isolated nine times from the cold water of six water purifies (a total of 12 water purifiers). Bacteria identified by MALDI-TOF MS included anaerobic bacteria (Clostridium novyi, Clostridium themopalmarium etc.), Gram-positive bacilli (Microbacterium testaceum, Arthrobacter woluwensis etc.), and Gramnegative bacilli (Acinetobacter nosocomialis, Comamonas kerstersii etc.), which are difficult identify by biochemical methods. In conclusion, bacteria exceeding the acceptable standard were isolated from the cold water of most of the water purifiers. Most of the isolated bacteria were low-pathogenic bacteria from natural environment, but opportunistic bacteria that can cause infection in humans were also isolated from some water purifiers.

• 디지털콘텐츠학회 논문지
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• 제13권1호
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• pp.1-11
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• 2012

웹사이트의 게시판은 각종 정보를 올리고 공유할 수 있는 정보소통의 장이다. 지금 이 순간에도 수많은 정보들이 각종 웹사이트의 게시판을 통해 공유되고 있다. 웹 게시판에 등록되어 공유된 정보는 누군가에게는 득이 될 수 있고 또 누군가에게는 실이 될 수 있다. 이러한 이유로 웹 게시판에 등록되는 정보에 대하여 실시간으로 모니터링하고 그 결과를 알려주는 기술에 대한 연구가 오래 전부터 있어 왔다. 기존의 방법들은 DB에 직접 접근하는 방법과 오픈API를 이용하는 방법으로 게시판을 모니터링 하였다. 또한 이를 사용자에게 알려주기 위해 이메일을 이용하는 방법을 사용하였다. 이러한 방법에는 두 가지 큰 문제가 있다. 오픈되지 않은 게시판에 접근할 수 없는 문제와 사용자에게 실시간으로 알려주기 어렵다는 문제이다. 특히나 모니터링과 같은 서비스는 실시간성이 매우 중요하다. 왜냐하면 모니터링의 목적은 그에 대한 대응을 기본적으로 하고 있기 때문이다. 모바일 웹은 언제 어디서나 접속할 수 있다는 장점으로 인하여 실시간적인 요소가 필요한 서비스에 적합하다. 하지만 휴대폰 단말기에 따라 콘텐츠의 규격이 다르다는 단점으로 인하여 콘텐츠를 미리 생성해야 하기 때문에 이러한 실시간적인 서비스에 잘 이용하지 못하였다. 본 논문은 비 규격화된 모바일 웹의 단점을 극복하는 기술을 제시함으로서 모니터링과 같은 실시간성이 필요한 서비스에 모바일웹을 이용하여 그 효과를 극대화하는 모습을 보여주고자 한다.

• 해양환경안전학회지
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• 제25권2호
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• pp.237-243
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• 2019

PE(PolyEthylene) 재료를 활용한 해상부유 구조물은 바다, 강 또는 호수의 인근이나 수역 내에 일정한 공간 부를 형성하는 부유식 구조물로, 현재는 그 용도가 소형선박 계류장뿐만 아니라 양식장, 수상 펜션, 해상부교 등에 다양하게 활용되고 있다. 이 제품군의 특징은 유연성이 뛰어나고 재활용할 수 있으며, 내약품성, 내후/내식성이 우수하다. 기존의 PE 제품군을 활용한 부유식 플랫폼은 한 개의 브래킷에 한 개의 부력관을 체결하는 단순한 구조를 구성하였고, 이로 인하여 사용자가 용도 변경 및 사용환경이 변경될 때는 적용하는데 제한이 있었다. 이에 본 연구에서는 한 개의 브래킷에 다양한 크기를 갖는 부력 관을 체결할 수 있는 구조를 개발하고, 제품의 구조 안전성을 유한요소법을 활용하여 검증하였다. 구조해석 결과, 브래킷 하단에 지름 500 mm 부력관 모델에서 충돌 하중에 대해 최대값을 나타내었으나, 허용기준을 만족하였다. 본 연구 결과를 기반으로 하여, 향후 다양한 형태의 부유체 플랫폼에 대한 구조 안전성 평가에 관한 연구가 가능하며, 관련 평가 기준에 대한 정립이 필요하다.

• 한국컴퓨터정보학회논문지
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• 제29권4호
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• pp.83-89
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• 2024

인터넷 익스플로러의 서비스 종료 이후 ActiveX의 사용이 종료됨에 따라 Non-ActiveX 정책이 확산되었다. Non-ActiveX 정책을 바탕으로 정해진 웹 페이지 표준 규약으로 HTML5가 채택되어 사용되고 있다. W3C(World Wide Web Consortium)에서 개발된 HTML5는 다양한 기능을 플러그인 없이 브라우저만으로 쉽게 사용할 수 있고, 기존 HTML에 비해 다양한 요소와 속성이 추가되었으며 API를 통해 더 나아진 웹 응용 환경을 제공하고 있다. 그러나 새로 추가된 기술들로부터 새로운 보안 취약점이 발견되었고, 이러한 취약점으로 인하여 공격 범위가 넓어졌다. HTML5가 적용된 웹 사이트에서 발생할 수 있는 보안 취약점을 찾기 위한 연구가 부족하다. 본 논문은 최근 5년 이내에 플러그인이 제거된 공공기관 웹 페이지를 대상으로 웹 페이지의 보안 취약점을 탐지하고 분석하여 웹 취약점을 가지는 태그 및 속성을 탐지하는 모델을 제안한다. 제안된 모델을 웹 페이지에 적용한다면 플러그인 제거 후에도 현재까지 웹 페이지의 웹 표준 준수 여부 및 취약점을 분석할 수 있어 신뢰성 있는 웹 서비스를 제공할 수 있다. 그리고 해킹 피해로 인한 금전적, 물리적 문제들을 예방하는 데 도움이 될 것으로 기대된다.

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 1994년도 교수 연수회(환경)
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• pp.681-691
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• 1994

The American Conference of Governmental Industrial Hygienists (ACGIH) has proposed a threshold limit value (TLV) for benzene of 0.1 ppm. Individuals representing the American Petroleum Institute (API)and the Chemical Manufacturers Association (CMA) have argued that 1) the risk assessment by Rinsky .et al. which ACGIH partially relied upon for its proposed TLV overestimates the risk; however, at the exposures levels of interest - (e.g., 0.1 to 1.0 ppm) for establishing a benzene TLV, the Rinsky et al. assessment provides lower estimates of leukemia risk than most others; 2) ACGIH should not use the Dow study for direct observational evidence of leukemia risk associated with low-level benzene exposure because of confounding exposure; however, it is unlikely that confounding exposures played a role in the excess of leukemia demonstrated in the study, and the Dow cohort was exposed to an average benzene concentration of about 5.5 ppm benzene for 7.11 years (31:1.5 ppm-years), while some of the individuals in the study who died from leukemia were exposed to an average of only 1.0 ppm without the opportunity for highpeak exposures; 3) the Occupational Safety and Health Administration (OSHA) established an 8-hour time-weighted average (TWA) of 1.0 ppm in 1987, and there is no new evidence that would justify reducing the TWA below that level; however, the OSHA TWA of 1.0 ppm was based on economic feasibility and the level of excess risk remaining at 1.0 ppm, i.e., 10 excess leukemia deaths per 1000 workers over an occupational lifetime (45 years) according to OSHA's preferred estimate leaves behind I risk considered significant by OSHA. In addition, chromosomal studies among workers and in animals exposed to benzene indicate that low-level exposure, i.e., 1.0 ppm, is associated with elevated Cytogenetic damage. On the basis of adverse health effects data alone, in this author's opinion, it would be poor science and poor public health policy to establish a benzene TLV greater than 0.1 ppm.

• 한국약용작물학회지
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• 제25권2호
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• pp.108-114
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• 2017

Background: The study was conducted to investigate the distributions of faecal bacteria in commercial oriental medicine herb products. Methods and Results: A survey was conducted on the microbial contamination levels and antimicrobial specificity of Bacillus cereus and other microbes using 106 oriental medicine herb products on sale in Seoul. Pouring and isolation methods such as standard plate counts were used to identify the bacteria. The isolated bacterias included coliforms, Bacillus spp., Enterococcus spp., Staphylococcus spp., Listeria spp.were identified by using gram staining and an API (analytical profile index) kit. Antimicrobial drugs discs were determined by CLSI (clinical and laboratory standards institute). Conclusions: The bacterial isolates present in the herbal medicines included 98 coliforms, 45 Bacillus spp., 29 Enterococcus spp., and 2 Listeria spp. Among these, there were nine Bacillus cereus strains, one Enterococcus faecium strain, and one Enterococcus faecalis strain present. The 9 Bacillus cereus strains were tested for susceptibility to 36 types of antibiotics products by the disc diffusion method. The strains showed resistance to 13 of these antibiotic products and semi-resistance to 5 antibiotic products. On the basis of these results, any oriental medicine herb product can be assumed to be contain resistant or semi-resistant bacterial strains. Therefore, we suggest prescribing guidelines and special management for the use of antibiotics in farms producing oriental medicine herb products.

• 한국해양공학회지
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• 제17권2호
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• pp.34-39
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• 2003

Recent deepwater offshore structures in the Gulf of Mexico utilize butt welded tubular joints. Application of a welded tubular joint includes tendons, production risers, and steel catenary risers. Fatigue life assessment of these joints becomes more critical, as the structures to which they are attached are allowed to undergo cyclic and sometimes large displacements around an anchored position. Estimation of the fatigue behavior of these tubular members in the design stage is generally condrcted by using S-N curves, as specified in the codeds and standards. Applying the stress concentration factor of the welded structure to the S-N approach often results in a very conservative assessment, because the stress field acting on the tubular has a non-uniform distribution through the thickness. Fatigue life analysis using fracture mechanics has been applied in the design of the catenary risers. This technology enables the engineer to establish proper requirements on weld quality and inspection acceptance criteria to assure satisfactory structural integrity during its design life. It also provides guidance on proper design curves and a methodology for accounting for the effects of non-uniform stress distribution through the wall thickness. Still, there is inconsistency when designing tubular joints using a conventional S-N approach and when specifying weld flaw acceptance criteria using fracture mechanics approach. This study developed fatigue curves that are consistent with both the S-N approach and the fracture mechanics approach. Accounting for non-uniform stress distribution and threshold stress intensity factor were key parameters in relating both approaches. A series of S-N curves, generated from the fracture mechanics approach, were compared to the existing S-N curves. For flat plate butt joint, the S-N curve generated from fracture mechanics matches with the IIW class 100 curve when initial crack depth was 0.5 mm (0.02 ). The new curves for tubular joint agree very well with the experimental results. The comparison also indicated the degree of conservatism built into the API X design curve.