• Nuclear Engineering and Technology
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• 제46권3호
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• pp.313-342
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• 2014

A Nuclear Energy Agency (NEA), Organization for Economic Co-operation and Development (OECD) benchmark for Uncertainty Analysis in Modeling (UAM) is defined in order to facilitate the development and validation of available uncertainty analysis and sensitivity analysis methods for best-estimate Light water Reactor (LWR) design and safety calculations. The benchmark has been named the OECD/NEA UAM-LWR benchmark, and has been divided into three phases each of which focuses on a different portion of the uncertainty propagation in LWR multi-physics and multi-scale analysis. Several different reactor cases are modeled at various phases of a reactor calculation. This paper discusses Phase I, known as the "Neutronics Phase", which is devoted mostly to the propagation of nuclear data (cross-section) uncertainty throughout steady-state stand-alone neutronics core calculations. Three reactor systems (for which design, operation and measured data are available) are rigorously studied in this benchmark: Peach Bottom Unit 2 BWR, Three Mile Island Unit 1 PWR, and VVER-1000 Kozloduy-6/Kalinin-3. Additional measured data is analyzed such as the KRITZ LEU criticality experiments and the SNEAK-7A and 7B experiments of the Karlsruhe Fast Critical Facility. Analyzed results include the top five neutron-nuclide reactions, which contribute the most to the prediction uncertainty in keff, as well as the uncertainty in key parameters of neutronics analysis such as microscopic and macroscopic cross-sections, six-group decay constants, assembly discontinuity factors, and axial and radial core power distributions. Conclusions are drawn regarding where further studies should be done to reduce uncertainties in key nuclide reaction uncertainties (i.e.: $^{238}U$ radiative capture and inelastic scattering (n, n') as well as the average number of neutrons released per fission event of $^{239}Pu$).

• 한국전자통신학회논문지
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• 제7권3호
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• pp.499-505
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• 2012

TPMS(Tire Pressure Monitoring System)는 차량에서 사용되는 무선통신기기의 일종으로 운전자가 타이어의 상태를 보다 효율적으로 파악하고 관리하기위한 안전보조 시스템으로 정의할 수 있다. TPMS는 무선통신을 사용하므로 데이터 송/수신 시 각종 잡음이나 간섭에 의한 통신장애가 발생하게 된다. 운전자의 안전과 직결되는 타이어 사고를 사전에 예방하고 무선통신으로 인한 데이터 전송 시 보다 정확한 데이터 신뢰성 확보를 위해 본 논문에서는 신호처리수신부에서 수신신호의 SINR(signal-to-interference and noise ratio, 신호 대 간섭 및 잡음 비)을 측정하여 데이터 신뢰도를 판정하는 신뢰도 판정기법을 제안한다. 또한, 이를 수행하기 위한 효과적인 데이터 신뢰성 판정 알고리즘 구조를 제안한다. 본 논문에서 제안된 데이터 신뢰성 판정기법은 TPMS 뿐만 아니라 센서를 이용한 양방향통신 시스템에서 폭넓게 사용될 수 있을 것으로 판단되다. 컴퓨터 시뮬레이션을 통해 95%, 97%, 99%의 데이터 신뢰도를 만족하는 임계 SINR 값을 확인한다.

• 대한핵의학회지
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• 제36권1호
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• pp.74-79
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• 2002

In addition to the well-established use of positron emission tomography (PET) in clinical oncology, novel roles for PET are rapidly emerging in the field of gene therapy. Methods for controlled gene delivery to living bodies, made available through advances in molecular biology, are currently being employed in animals for research purposes and in humans to treat diseases such as cancer. Although gene therapy is still in its early developmental stage, it is perceived that many serious illnesses could be treated successfully by the use of therapeutic gene delivery. A major challenge for the widespread use of human gene therapy is to achieve a controlled and effective delivery of foreign genes to target cells and subsequently, adequate levels of expression. As such, the availability of noninvasive imaging methods to accurately assess the location, duration, and level of transgene expression is critical for optimizing gene therapy strategies. Current endeavors to achieve this goal include methods that utilize magnetic resonance imaging, optical imaging, and nuclear imaging techniques. As for PET, reporter systems that utilize genes encoding enzymes that accumulate positron labeled substrates and those transcribing surface receptors that bind specific positron labeled ligands have been successfully developed. More recent advances in this area include improved reporter gene constructs and radiotracers, introduction of potential strategies to monitor endogenous gene expression, and human pilot studies evaluating the distribution and safety of reporter PET tracers. The remarkably rapid progress occurring in gene imaging technology indicates its importance and wide range of application. As such, gene imaging is likely to become a major and exciting new area for future application of PET technology.

• 한국산업보건학회지
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• 제4권1호
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• pp.117-126
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• 1994

Some of the important and vital roles performed by the Health Care Center of Pohang Iron & Steel Co., Ltd.(POSCO) are the periodic monitoring of the work sites as well as regular medical check-ups for each workers to ensure both pleasant and safe working conditions and to protect employees' health. Pohang Steel Works, which has 42 plants, 26 facilities and 12,000 employees, has an annual crude steel production capacity of 9,670,000 using 24,500,000 ton of raw materials. We have measured lots of areal and personal working environment according to Occupational Safety and Health Law semiannually. All data collected on industrial hygiene is stored and managed by personal computer. The developed of a computerized industrial hygiene control system linked to the company's main computer system will provide efficient evaluation of the working environment as well as critical informations on employees' health. Development of this system had begun in May, 1992 and was completed in March, 1994. The computerized industrial hygiene control system can; 1. store industrial hygiene data, providing key pertinent to the diagnosis of occupational related illnesses, and if necessary, the basis for improving the working environment, 2. decide type and time of medical examination of each work for exposure to specific agents, and supply proper protection periodically, 3. prevent occupational related illnesses through evaluation of environmental and biological monitoring, and performance of epidemiological surveillance, 4. facilitate proper job placement through linking of industrial hygiene control and personnel information systems, 5. monitor job processes. levels of chemical agents used, and new agents introduced, 6. and increase productivity by saving time resulting from the implementation of the computerized sysyte,

• 비파괴검사학회지
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• 제33권1호
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• pp.63-68
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• 2013

Some essential components in nuclear power plants are periodically inspected using non-destructive examinations, for example ultrasonic, eddy current and radiographic examinations, in order to determine their integrity. These components include nuclear power plant items such as vessels, containments, piping systems, pumps, valves, tubes and core support structure. Steam generator tubes have an important safety role because they constitute one of the primary barriers between the radioactive and non-radioactive sides of the nuclear power plant. There is potential that if a tube bursts while a plant is operating, radioactivity from the primary coolant system could escape directly to the atmosphere. Therefore, in-service inspections are critical in maintaining steam generator tube integrity. In general, the eddy current testing is widely used for the inspection of steam generator tubes due to its high inspection speed and flaw detectability on non-magnetic tubes. However, it is not easy to analyze correctly eddy current signals because they are influenced by many factors. Therefore, the performance of eddy current data analysts for steam generator tubing should be demonstrated comprehensively. In Korea, the performance of steam generator tubing analysts has been demonstrated using the Qualified Data Analyst program. This paper describes the performance demonstration program for steam generator tubing analysts and its implementation results in Korea. The pass rate of domestic analysts for this program was 71.4%.

• 대한한의학회지
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• 제33권3호
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• pp.200-230
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• 2012

Objectives: Ginseng, Panax ginseng C. A., white ginseng, has been used for thousands of years in Traditional Korean Medicine. Red ginseng can be made by a steaming process of white ginseng changing a variety of ginsenosides and ingredients such as dencichine. This article reviews red ginseng for mechanisms for pharmacodynamics and toxicity based on the content of ginseng's active ingredients, ginsenoside changed by steaming. Methods: The following electronic databases were searched: PubMed, Science Direct and Chinese Scientific Journals full text database (CQVIP), and KSI (Korean Studies Information) from their respective inceptions to June 2012. Results: Compared with unsteamed ginseng, the content of ginsenosides Rg2, Rg3, Rg5, Rh1, Rh2 and Rk1 called red ginseng-specific ginsenosides increased after the steaming process. Different ginsenosides have shown a wide variety of effects such as lowering or raising blood sugar and blood pressure or stimulating or sedating the nervous system. Especially, the levels of Rg2, Rg3, Rg5, Rh1, Rh2 and Rk1 were increased by the steaming process, showing a variety of pharmacodynamics in biological systems. Also, various processing methods such as puffing and fermentation have been developed in processing crude ginseng or red ginseng, affecting the content of ginseng's ingredients. The safety issue could be the most critical, specifically, on changed ginseng's ingredients such as dencichine. The level of dencichine was significantly reduced in red ginseng by the steaming process. In addition, the possible toxicity for red ginseng was affected by cytochrome P450, a herbal-drug interaction. Conclusions: The variety of pharmacological and toxicological properties should be changed by steaming process of Panax ginseng C. A., white ginseng. Even if it is not sure whether the steaming process of white ginseng would be better pharmacologically, it is sure that steaming reduces the level of dencichine causing a lower toxicity to the nervous system.

• 한국정보컨버전스학회:학술대회논문집
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• 한국정보컨버전스학회 2008년도 International conference on information convergence
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• pp.63-70
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• 2008

The authors, Tom Karygiannis of NIST, and Bernard Eydt, Greg Barber, Lynn Bunn, and Ted Phillips of Booz Allen Hamilton, wish to thank Steven Fick, Rick Korchak, Kate Remley, Jeff Guerrieri, Dylan Williams, Karen Scarfone, and Tim Grance of NIST, and Kenneth Waldrop and Beth Mallory of Booz Allen Hamilton. These individuals reviewed drafts of this document and contributed to its technical content. The authors would also like to express their thanks to several experts for their critical review and feedback on drafts of the publication. These experts include V.C. Kumar of Texas Instruments; Simson Garfinkel of the Naval Postgraduate School; Peter Sand of the Department of Homeland Security; Erika McCallister of MITRE; and several professionals supporting Automatic Identification Technology(AIT) program offices within the Department of Defense(DoD), especially Nicholas Tsougas, Fred Naigle, Vince Pontani, Jere Engelman, and Kathleen Smith. During the public comment period we received helpful comments from the following Federal Government agencies: the US Departments of Defense, Health and Human Services, Homeland Security, Labor, and State; the Office of the Director of National Intelligence; the Office of Management and Budget; and the General Services Administration. We also received several helpful contributions from commercial industry, including comments from EPCglobal, VeriSign, and Priway. Finally, the authors wish to thank the following individuals for their comments and assistance: Brian Tiplady, Daniel Bailey, Paul Dodd, Craig K. Harmon, William MacGregor, Ted Winograd, Russell Lange, Perry F. Wilson, John Pescatore, Ronald Dugger, Stephan Engberg, Morten Borup Harning, Matt Sexton, Brian Cute, Asterios Tsibertzopoulos, Mike Francis, Joshua Slob in, Jack Harris, and Judith Myerson.

• 산업경영시스템학회지
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• 제32권2호
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• pp.120-131
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• 2009

Most world-leading companies are aware that Environment and Health and Safety Issues are critical to the product quality and sustainable growth of their company. Environment-friendly efforts are seen in almost all aspects of business operations in an advanced nation. The Extended Producer Responsibility(EPR) and EU Directive on Waste Electric and Electronic Equipment(WEEE) attempt to tackle the growing quantity of WEEE by making producers responsible for the costs of the collection and recycling of their products at the End-of-Life(EOL). To implement the RFID-based integration system for EOL household electric appliances, such as washing machines and refrigerators, we analyzed the process of collecting, recovering, and recycling the EOL products returned from the distribution points. Furthermore, we proposed a soon-to-be process using the RFID-based integration system in the metropolitan recycling center(MRC). This soon-to-be process model is composed of RFID tags, readers, ALEs, applications and several devices. Through the introduction of the RFID-based integration system, we are expecting to see increasing traceability and real-time management for EOL products from customers, and also improvements in valuable reusable materials(VRM) produced from recycling processes.

• Smart Structures and Systems
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• 제17권6호
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• pp.917-933
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• 2016

In a prestressed concrete bridge, the magnitude of the prestress force (PF) decreases with time. This unexpected loss can cause failure of a bridge which makes prestress force identification (PFI) critical to evaluate bridge safety. However, it has been difficult to identify the PF non-destructively. Although some research has shown the feasibility of vibration based methods in PFI, the requirement of having a determinate exciting force in these methods hinders applications onto in-service bridges. Ideally, it will be efficient if the normal traffic could be treated as an excitation, but the load caused by vehicles is difficult to measure. Hence it prompts the need to investigate whether PF and moving load could be identified together. This paper presents a synergic identification method to determine PF and moving load applied on a simply supported prestressed concrete beam via the dynamic responses caused by this unknown moving load. This method consists of three parts: (i) the PF is transformed into an external pseudo-load localized in each beam element via virtual distortion method (VDM); (ii) then these pseudo-loads are identified simultaneously with the moving load via Duhamel Integral; (iii) the time consuming problem during the inversion of Duhamel Integral is overcome by the load-shape function (LSF). The method is examined against different cases of PFs, vehicle speeds and noise levels by means of simulations. Results show that this method attains a good degree of accuracy and efficiency, as well as robustness to noise.

• 인터넷정보학회논문지
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• 제13권4호
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• pp.95-102
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• 2012

차량 애드 혹 네트워크(VANETs)를 위한 응용들의 개발은 지능적 안전 운송시스템 제공이라는 매우 제한적인 명확한 목표를 가지고 있다. 공공의 안전을 위한 긴급경고 기술은 제한된 시간에 신속하고 효율적으로 경고 메세지를 전달하는 지능형 방송 기법을 필요로 하는 응용중의 하나이다. VANETs 방송 프로토콜 설계 시에 접근제어 계층에서 여러 노드들이 동시에 전송을 시도할 경우, 다수 패킷들의 충돌과 여분의 지연을 발생하는 방송폭풍 문제가 고려되어야 한다. 본 논문에서는, 효율적으로 방송폭풍 문제와 시간 한계를 해결할 수 있는 조기 지능형 경보 방송(EI-CAST) 알고리즘을 제안한다. 제안 알고리즘은 충돌시간(TTC)에 기초한 조기경보 기술과 퍼지논리에 기초한 지능형 방송 기술을 사용하며, 시뮬레이션을 통해 제안 알고리즘과 기존 경보방송 알고리즘의 성능을 비교 평가 하였다. 실험결과 제안 알고리즘의 경우 경보 전송거리 4 km 이내의 차량들은 사고발생 이전에 경보메시지를 수신할 수 있으며 패킷 충돌이 없음을 확인할 수 있었다.