• 한국인터넷방송통신학회논문지
• /
• 제22권3호
• /
• pp.93-98
• /
• 2022

최근 옵테인 등 고속 스토리지의 출현으로 하드디스크에 적합하게 설계된 메모리 시스템 설정에 대한 재고가 필요한 시점에 이르렀다. 본 논문에서는 고속 스토리지의 탑재에 따라 페이지 크기가 메모리 시스템의 성능에 어떠한 영향을 미치는지를 분석하고, 가상화 환경에서 워크로드 상황에 맞게 페이지 크기를 설정할 수 있는 모델을 설계하였다. 전통적인 시스템의 경우 워크로드 별로 페이지 크기를 설정하는 것이 쉬운 일이 아니지만 최근 클라우드 환경의 활성화로 개별 워크로드 수행을 위해 별도의 가상머신이 생성되므로 가상머신이 시작될 때 해당 가상머신의 페이지 크기를 결정할 수 있어 제안한 모델의 효용이 높을 것으로 기대된다. 다양한 가상머신 시나리오에 대한 시뮬레이션 실험을 통해 제안한 모델이 워크로드 상황에 맞게 페이지 크기를 설정하여 메모리 접근 시간을 크게 개선함을 보인다.

• Nuclear Engineering and Technology
• /
• 제47권4호
• /
• pp.479-487
• /
• 2015

The thallium-doped sodium iodide [NaI(Tl)] scintillation detector is preferred as a gamma spectrometer in many fields because of its general advantages. A silicon photomultiplier (SiPM) has recently been developed and its application area has been expanded as an alternative to photomultiplier tubes (PMTs). It has merits such as a low operating voltage, compact size, cheap production cost, and magnetic resonance compatibility. In this study, an array of SiPMs is used to develop an NaI(Tl) gamma spectrometer. To maintain detection efficiency, a commercial NaI(Tl) $2^{\prime}{\times}2^{\prime}$ scintillator is used, and a light guide is used for the transport and collection of generated photons from the scintillator to the SiPMs without loss. The test light guides were fabricated with polymethyl methacrylate and reflective materials. The gamma spectrometer systems were set up and included light guides. Through a series of measurements, the characteristics of the light guides and the proposed gamma spectrometer were evaluated. Simulation of the light collection was accomplished using the DETECT 97 code (A. Levin, E. Hoskinson, and C. Moison, University of Michigan, USA) to analyze the measurement results. The system, which included SiPMs and the light guide, achieved 14.11% full width at half maximum energy resolution at 662 keV.

• 한국디지털정책학회:학술대회논문집
• /
• 한국디지털정책학회 2007년도 춘계학술대회
• /
• pp.127-143
• /
• 2007

As the informationized society develops, for companies to be industrially competitive in global competition, innovation of business administration through informationization is a nation-wide task that must be driven. Small-to-mid size companies also tend to recognize the need for informationization and build the information systems, improving their informationization levels. To reduce errors in bringing in and running the information systems and increase efficiency In using them, the need for the standard and guide for informationization in small-to-mid size companies has increased. Accordingly, the national office of small and medium business administration has developed the informationized management system (IMS) certification standard in order to provide a national motive to secure the means for management innovation of small-to-mid size companies and have them recognize informationization as a business strategy. Now, there arises the need for the IMS certification standard, which was developed in early 2000, due to changes in environments of small-and-medium businesses and problems that have been revealed in field applications. In this research, we have examined the current situations of informationization in small-and-medium businesses that were revealed by the 2005 survey on the levels of informationization in small and medium business, have drawn the problems that have occurred in the process of applying the IMS in many small-to-mid size companies, have devised the measures against those problems, and have proposed a new IMS certification standard that reflects those measures. This research has proposed only the direction for development of the IMS certification standard. Future researches should deal with detailed items and criteria for evaluation and continuous improvement of them.

• 복식문화연구
• /
• 제31권3호
• /
• pp.296-309
• /
• 2023

This study gathered basic information on the development of Jiu-Jitsu uniforms suitable for players in Korea. Detailed data were collected between December 20^th and December 30^th, 2022 on 21 selected brands sold in online shopping malls. For each, information was recorded on the production country, product type, price, colors, material, and sizing system. A total of 612 datasets were analyzed using frequency analysis, cross-tabulation, and Chi-square tests. Jiu-Jitsu uniforms were classified as either standard or limited edition. Limited edition uniforms were more expensive than regular uniforms. International brands had a higher price range than domestic brands. The most commonly used colors for Jiu-Jitsu uniforms were the regulation colors associated with the sport: white, black, and blue. Domestic brands were more likely to use non-regulation colors than international brands. The material used for the top half of the uniform was predominantly pearl weave, while the bottom half was usually ripstop. International brands used a more diverse range of materials than domestic brands. The Jiu-Jitsu uniform sizing system incorporated a range of sizes between A00 and A6. While sizing designations differed according to the established sizing systems of different countries, the sizes remained the same, as did the range of sizes available. Where size guides were provided, height and weight were used to help the customer determine the appropriate size. The dimensions of each size varied between brands. Overall, we found that international brands offer a more diverse range of Jiu-Jitsu uniform designs than domestic brands.

• 대한간호학회지
• /
• 제43권5호
• /
• pp.587-594
• /
• 2013

Purpose: The purpose of this study is to provide researchers with a simplified approach to undertaking exploratory factor analysis for the assessment of construct validity. Methods: All articles published in 2010, 2011, and 2012 in Journal of Korean Academy of Nursing were reviewed and other relevant books and articles were chosen for the review. Results: In this paper, the following were discussed: preliminary analysis process of exploratory factor analysis to examine the sample size, distribution of measured variables, correlation coefficient, and results of KMO measure and Bartlett's test of sphericity. In addition, other areas to be considered in using factor analysis are discussed, including determination of the number of factors, the choice of rotation method or extraction method of the factor structure, and the interpretation of the factor loadings and explained variance. Conclusion: Content validity is the degree to which elements of an assessment instrument are relevant to and representative of the targeted construct for a particular assessment purpose. This measurement is difficult and challenging and takes a lot of time. Factor analysis is considered one of the strongest approaches to establishing construct validity and is the most commonly used method for establishing construct validity measured by an instrument.

• Ocean and Polar Research
• /
• 제27권3호
• /
• pp.323-333
• /
• 2005

The paper is to serve as a guide for deciding on a desirable direction for the vessel buyback program, reviewing their performance and economic effects from fish harvest reduction due to not reaching MSY. Compared with maximum willingness to pay for vessel buyback programs designed to avoid economic losses occurring as a result of overfishing, the portions of investment costs for buyback program are so small comparatively to the range of 0.32% to 12.19% at the annual base. The economic loss effects occurred in terms of the reduction of fishing harvest are comprehensively estimated at the present value of 30,877 billion won since 1971, and exceeded the revenues for fish harvests from 1999. In order to resole fish stocks through a vessel buyback program, this paper recommends that the yield should be reduced to less than the intrinsic growth rate. Otherwise, the buyback program policy eventually fails regardless of the temporal effect of benefits. This paper further argues that technical policy tools such as fishing grounds, fishing seasons, size of fish and minimum size of meshes should be effectively utilized.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2007년도 춘계학술대회A
• /
• pp.1803-1806
• /
• 2007

The General roles of a spacer grid(SG) are providing a lateral and vertical support for fuel rods, promoting a mixing of coolant and keeping guide tubes straight so as not to impede a control rod insertion under any normal or accidental conditions. To evaluate the impact characteristics of a SG such as impact velocity, critical buckling strength and duration time, a few types of impact tests for SGs have been conducted. In a previous study, a new welding method, a through-welding method, was proposed to increase critical buckling strength of a SG without any design change or material change and was verified by impact tests with $7{\times}7$ partial SG specimens.In this paper, the effect of through-welding method in case of a $16{\times}16$ full-size SG is investigated by pendulum impact tests with $16{\times}16$ SG specimens. And the increase of critical buckling strength for full-size SGs is measured by comparison with impact results of spot-welded and through-welded SGs.

• 한국시뮬레이션학회논문지
• /
• 제17권3호
• /
• pp.85-94
• /
• 2008

본 연구는 컨테이너 터미널에서 사용될 수 있는 교착방지를 위한 알고리즘 개발을 목표로 하였다. 기존의 교착방지 알고리즘은 많은 계산시간을 소요한다는 단점을 극복하기 위하여 본 연구에서는 하나의 경로에 대해서 예약스케줄을 작성하여 두고 반복적으로 사용하는 예약 스케줄 표 방식을 제안하였다. 시뮬레이션 실험 결과 예약 스케줄 표 방식은 그때그때의 주행경로에 대한 예약스케줄링을 위하여 계산시간이 필요 없기 때문에 AGV의 실시간 운영을 위하여 유용한 방식임을 알 수 있었다.

• Korea-Australia Rheology Journal
• /
• 제19권3호
• /
• pp.171-176
• /
• 2007

LCD-BLU (Liquid Crystal Display-Back Light Unit) of medium size is usually manufactured by forming numerous dots with $50{\sim}300\;{\mu}m$ in diameter by etching process and V-grove shape with $50\;{\mu}m$ in height by mechanical cutting process. However, the surface of the etched dots is very rough due to the characteristics of the etching process and V-cutting needs rather high cost. Instead of existing optical pattern made by etching and mechanical cutting, 3-dimensional continuous micro-lens of $200\;{\mu}m$ in diameter was applied in the present study. The continuous micro-lens pattern fabricated by modified LIGA with thermal reflow process was tested to this new optical design of LGP. The manufacturing process using LIGA-reflow is made up of three stages as follows: (i) the stage of lithography, (ii) the stage of thermal reflow process and (iii) the stage of electroplating. The continuous micro-lens patterned LGP was fabricated with injection molding and its test results showed the possibility of commercial use in the future.

• Nuclear Engineering and Technology
• /
• 제38권4호
• /
• pp.353-358
• /
• 2006

Alpha track analysis for the determination of the trace amount of alpha emitting nuclides in a very small particle was performed as an efficient and powerful technique during safeguard inspection. Metal particles with well-defined spherical shape, size and isotopic compositions as a reference material were used to correlate the number of tracks or track diameter with an isotopic composition eventually to identify the uranium enrichment in the environmental swipe samples. Slopes in the number of tracks versus the exposure time curve provide a simple insight into the uranium enrichment of an unknown particle. Low enriched uranium metal particles result in slopes still steeper than the depleted or natural uranium metal particles. In addition, a linear relationship between track diameter and particle size Is thought to be a useful first stage analytical tool as an efficient and convenient inspection guide. The significance of the simple linear model was also judged using the usual statistical tests.