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On an Enhanced Model of System Readiness Level by Incorporating Safety for the Development of Live Fire Test Systems (실사격 시험시스템의 효율적인 개발을 위해 안전도 반영을 통해 개선된 시스템 성숙도 모델에 관한 연구)

  • Ye, Sung Hyuck;Lee, Jae-Chon
    • Journal of the Korea Safety Management & Science
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    • v.17 no.3
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    • pp.195-204
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    • 2015
  • The live fire test has been playing a critical role in evaluating the goals-to-meet of the weapon systems which utilize the power of explosives. As such, the successful development of the test systems therein is quite important. The test systems development covers that of ranges and facilities including system-level key components such as mission control, instrumentation or observation, safety control, electric power, launch pad, and so on. In addition, proper operational guidelines are needed with well-trained test and operation personnel. The emerging weapon systems to be deployed in future battle field would thus have to be more precise and dynamic, smarter, thereby requiring more elaboration. Furthermore, the safety consideration is becoming more serious due to the ever-increasing power of explosives. In such a situation, development of live fire test systems seems to be challenging. The objective of the paper is on how to incorporate the safety and other requirements in the development. To achieve the goal, an architectural approach is adopted by utilizing both the system components relationship and safety requirement when advanced instrumentation technology needs to be developed and deteriorated components of the range are replaced. As an evaluation method, it is studied how the level of maturity of the test systems development can be assessed particularly with the safety requirement considered. Based on the concepts of both systems engineering and SoS (System-of-Systems) engineering process, an enhanced model for the system readiness level is proposed by incorporating safety. The maturity model proposed would be helpful in assessing the maturity of safety-critical systems development whereas the costing model would provide a guide on how the reasonable test resource allocation plan can be made, which is based on the live fire test scenario of future complex weapon systems such as SoS.

A Comparison Study of Various Water Sources for Feasibility of Expanding the use of Groundwater in Public Water Supply of South Korea (지하수 상수원 활용의 타당성 고찰을 위한 상수도 취수원의 특성 비교 연구)

  • Cha, Eun-Jee;Hyun, Yunjung
    • Journal of Soil and Groundwater Environment
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    • v.22 no.4
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    • pp.60-70
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    • 2017
  • As water sources become more vulnerable to the effects of climate change such as drought and contamination, the diversification of water sources is important for securing water supply. This study examines the properties of five water sources for public supply, including river and river-bed water, dams, reservoirs, and groundwater, while ensuring that the quantities available from such sources are stable and the water itself is safe for use. This study also analyzes the power, chemical, repair and maintenance, and labor costs associated with each water source. The results demonstrate that groundwater has high potential as a water source because it is readily available (about $12.89billion\;m^3/yr$), but only a small portion of it is currently used. Analyses indicated that groundwater is the most efficient source of water to meet water demand below $1,000,000m^3/yr$, which covers 62.5% of water supply facilicities. With the implementation of groundwater dams, groundwater can become cost-efficient even for larger water demand. Additionally, the water source protection areas are the smallest for groundwater among the five water sources. In conclusion, the use of groundwater as an alternative water source is feasible becasue it is readily available, safe, cost-efficient, and requires the lowest amount of environmental regulations for the diversification of water supply sources.

Numerical Analysis for Supercavitation Characteristics around Underwater Vehicle according to Ventilated Gas Temperature (분사가스 온도에 따른 수중운동체 주위 초공동 특성 분석을 위한 수치해석)

  • Hwang, Hyunsung;Park, Warngyu;Nguyen, Van Tu;Kim, Donghyun;Nguyen, Duy Trong
    • Journal of the Korea Institute of Military Science and Technology
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    • v.25 no.5
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    • pp.487-500
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    • 2022
  • Supercavitation is a phenomenon in which the cavity covers the entire underwater vehicle. The purpose of this paper is to compare and analyze the thermal effect on the cavity characteristics by changing the ventilated gas temperature through computational analysis. For this study, a homogeneous mixture model based on the 3D Navier-Stokes equation was used. As a phase change model, it is its own code considering both pressure change and temperature change. A dimensionless number Tm was presented to analyze the numerical results, and as the Tm increased, the cavity length increased by about 3.6 times and the cavity width by about 3.3 times at 393.15 K compared to room temperature. Analyzing these thermal effects, it was confirmed that rapid heat exchange and heat transfer between the gas phase and the liquid phase occurred at the location where the ventilated gas was sprayed, affecting the cavity characteristics. In addition, it can be confirmed that the initial cavity surface becomes unstable as the ventilated gas temperature increases, and it can be confirmed based on the numerical analysis results that the critical temperature at which the cavity surface becomes unstable is 373.15 K.

Effects of Encapsulation Layer on Center Crack and Fracture of Thin Silicon Chip using Numerical Analysis (봉지막이 박형 실리콘 칩의 파괴에 미치는 영향에 대한 수치해석 연구)

  • Choa, Sung-Hoon;Jang, Young-Moon;Lee, Haeng-Soo
    • Journal of the Microelectronics and Packaging Society
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    • v.25 no.1
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    • pp.1-10
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    • 2018
  • Recently, there has been rapid development in the field of flexible electronic devices, such as organic light emitting diodes (OLEDs), organic solar cells and flexible sensors. Encapsulation process is added to protect the flexible electronic devices from exposure to oxygen and moisture in the air. Using numerical simulation, we investigated the effects of the encapsulation layer on mechanical stability of the silicon chip, especially the fracture performance of center crack in multi-layer package for various loading condition. The multi-layer package is categorized in two type - a wide chip model in which the chip has a large width and encapsulation layer covers only the chip, and a narrow chip model in which the chip covers both the substrate and the chip with smaller width than the substrate. In the wide chip model where the external load acts directly on the chip, the encapsulation layer with high stiffness enhanced the crack resistance of the film chip as the thickness of the encapsulation layer increased regardless of loading conditions. In contrast, the encapsulation layer with high stiffness reduced the crack resistance of the film chip in the narrow chip model for the case of external tensile strain loading. This is because the external load is transferred to the chip through the encapsulation layer and the small load acts on the chip for the weak encapsulation layer in the narrow chip model. When the bending moment acts on the narrow model, thin encapsulation layer and thick encapsulation layer show the opposite results since the neutral axis is moving toward the chip with a crack and load acting on chip decreases consequently as the thickness of encapsulation layer increases. The present study is expected to provide practical design guidance to enhance the durability and fracture performance of the silicon chip in the multilayer package with encapsulation layer.

A Real-Time Stock Market Prediction Using Knowledge Accumulation (지식 누적을 이용한 실시간 주식시장 예측)

  • Kim, Jin-Hwa;Hong, Kwang-Hun;Min, Jin-Young
    • Journal of Intelligence and Information Systems
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    • v.17 no.4
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    • pp.109-130
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    • 2011
  • One of the major problems in the area of data mining is the size of the data, as most data set has huge volume these days. Streams of data are normally accumulated into data storages or databases. Transactions in internet, mobile devices and ubiquitous environment produce streams of data continuously. Some data set are just buried un-used inside huge data storage due to its huge size. Some data set is quickly lost as soon as it is created as it is not saved due to many reasons. How to use this large size data and to use data on stream efficiently are challenging questions in the study of data mining. Stream data is a data set that is accumulated to the data storage from a data source continuously. The size of this data set, in many cases, becomes increasingly large over time. To mine information from this massive data, it takes too many resources such as storage, money and time. These unique characteristics of the stream data make it difficult and expensive to store all the stream data sets accumulated over time. Otherwise, if one uses only recent or partial of data to mine information or pattern, there can be losses of valuable information, which can be useful. To avoid these problems, this study suggests a method efficiently accumulates information or patterns in the form of rule set over time. A rule set is mined from a data set in stream and this rule set is accumulated into a master rule set storage, which is also a model for real-time decision making. One of the main advantages of this method is that it takes much smaller storage space compared to the traditional method, which saves the whole data set. Another advantage of using this method is that the accumulated rule set is used as a prediction model. Prompt response to the request from users is possible anytime as the rule set is ready anytime to be used to make decisions. This makes real-time decision making possible, which is the greatest advantage of this method. Based on theories of ensemble approaches, combination of many different models can produce better prediction model in performance. The consolidated rule set actually covers all the data set while the traditional sampling approach only covers part of the whole data set. This study uses a stock market data that has a heterogeneous data set as the characteristic of data varies over time. The indexes in stock market data can fluctuate in different situations whenever there is an event influencing the stock market index. Therefore the variance of the values in each variable is large compared to that of the homogeneous data set. Prediction with heterogeneous data set is naturally much more difficult, compared to that of homogeneous data set as it is more difficult to predict in unpredictable situation. This study tests two general mining approaches and compare prediction performances of these two suggested methods with the method we suggest in this study. The first approach is inducing a rule set from the recent data set to predict new data set. The seocnd one is inducing a rule set from all the data which have been accumulated from the beginning every time one has to predict new data set. We found neither of these two is as good as the method of accumulated rule set in its performance. Furthermore, the study shows experiments with different prediction models. The first approach is building a prediction model only with more important rule sets and the second approach is the method using all the rule sets by assigning weights on the rules based on their performance. The second approach shows better performance compared to the first one. The experiments also show that the suggested method in this study can be an efficient approach for mining information and pattern with stream data. This method has a limitation of bounding its application to stock market data. More dynamic real-time steam data set is desirable for the application of this method. There is also another problem in this study. When the number of rules is increasing over time, it has to manage special rules such as redundant rules or conflicting rules efficiently.

The Changeability of Fashion Style Using the Concept Expressed in the Mobility of 'la Différant' Play and Supplement Logic (차연적 놀이의 운동성과 대리보충 논리로 본 패션스타일의 가변성)

  • Park, Shinmi
    • Journal of the Korean Society of Costume
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    • v.65 no.3
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    • pp.28-46
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    • 2015
  • The aim of this research is to classify the concept expressed in the mobility of la diff${\acute{e}}$rant play, and supplement logic, which is process of the changeability of fashion style. The specific research questions are as follows: first question deals with the relationship between changeability and la diff${\acute{e}}$rant images, and how la diff${\acute{e}}$rant images are divided by each phase and how their circumduction play is proceeded. The second question is about the important features of the mobility of la diff${\acute{e}}$rant play and the method of la diff${\acute{e}}$rance play. The last topic of this study covers the supplement logic and the condition, and how supplement logic has been applied in the process of changeability of fashion style. This paper deploys a qualitative research method providing a systematic review of the previous studies. To sum it up, the mobility of la diff${\acute{e}}$rant play is the root of power, which is controlling the changeability of fashion style, and the objective of the play is to outline new la diff${\acute{e}}$rant images through spatialization of time. In addition, supplement logicis the method of la diff${\acute{e}}$rant play and the purpose of the logic is to harmonize 'ultimate la diff${\acute{e}}$rant image', which is the phenomenological construction stratum in the state of sub-conscious changeability, and 'immediate la diff${\acute{e}}$rant image', which is the structural construction level stratum in the state of external changeability. This research proves that the intrinsic attribute of changeability is contained the mobility of la diff${\acute{e}}$rant play and supplement logic.

Characteristics of Fur Design in the Contemporary Fashion -Mainly Focused on Works after the Year 2000- (현대패션에 나타난 모피디자인의 특성 -2000년 이후를 중심으로-)

  • Kim, Sun-Young
    • Journal of the Korean Society of Clothing and Textiles
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    • v.33 no.4
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    • pp.563-573
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    • 2009
  • This study analyzed the trends and aesthetic characteristics of fur design found in the contemporary fashion to examine the status of fur material in the contemporary fashion design, and through an analysis of the meaning it attempted to come up with a new viewpoint and form on material for the future fashion design. A literature review was used to explore the kinds and properties of furs. In addition, an empirical analysis of works that have appeared in fashion collections since the year 2000 was conducted with local and foreign fashion magazines such as Gap, Vogue, and Mode & Mode and other publications related to fashion collections. In the contemporary fashion, the trends of fur design are represented by use of various items, material combinations, application to decorative purposes(like trimmings, details, or accessories), and a wide range of colors and textures available by advanced dyeing and finishing techniques. The aesthetic values intrinsic to fur design are that the expression of conspicuous luxury covers even the qualitative aspect of luxury and adds fashionable images to casual items, contributing to the popularization of fur fashion, by using a variety of artificial furs; the expression of sensual feminine beauty allows the animal and primitive feel characteristic of furs to convert a feminine body into a sensual image of more than a simple biological impulse; and the expression of hybridity presents a new viewpoint through distortions, exaggerations, deviations from the existing constituent forms, or futuristic sensibilities in all elements of fashion design.

Past, Present, and Future of Psychosomatic Medicine in the Field of Korean Medical Education (한국 의학 교육에서 정신신체의학의 과거와 현재 그리고 미래)

  • Kim, Eui-Joong
    • Korean Journal of Psychosomatic Medicine
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    • v.20 no.1
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    • pp.14-17
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    • 2012
  • There were several documents that might reflect the great concern on the education of psychosomatic medicine in medical school from the 1960s. But the hour of class and proportion of psychosomatic medicine have been quite small among the total lecture time of psychiatry. Notwithstanding the importance of biopsychosocial perspective in practice and research there have been no agreement on the goal and content of teaching psychosomatic medicine in the medical school curriculum. Consultation-liaison psychiatric activity in the hospital were currently under-developed and educational content and process were not systematic. We should have established the goal of psychosomatic education in the medical school that includes making doctor who could not only cure disease but also care the ill patients. And we should develop the curriculum that covers essential area of psychosomatic medicine and checking system to monitor the process of education. With the continuance of psychosomatic perspectives from medical school education to clinical subspecialty we can make progress in this field.

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Study on Development of Crafts Cultural Industry - Central Region of South Korea Craft Industrial as center - (공예문화산업의 발전방안 연구 - 중부권 공예문화산업 중심으로 -)

  • Kim, Sung-Min
    • Journal of Digital Convergence
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    • v.14 no.5
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    • pp.385-390
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    • 2016
  • Cultural industry consists of a national own value and life style known as the cultural characteristics, and it has decorative and practical features so it covers necessaries and items of personal preference that the public use. Craft Culture Industry means the craft industry where goods with cultural features of traditional art are made based on specific region and surroundings, which is a series of process in which inherent traditional and cultural elements are produced, representing cultural industry. With the review on issues and solutions in each section of Craft Culture Industry, it would help solve the problem when developing Craft Culture Industry. This study examines the popularity and status of the craft cultural products and figures out the current situation of the domestic cultural industry and the development plan.

Location Strategy of Sports Oulets to Maximize the Market Share (시장 점유율을 최대로 할 수 있는 스포츠용품점 위치 결정 전략)

  • Lee, Sang-Un;Lee, Young-Sook;Choi, Seong-Beom;Han, Tae-Yong
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.13 no.3
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    • pp.93-101
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    • 2013
  • This paper suggests optimal location algorithm of new firm $A(F_A)^{\prime}s$ p(p$B(F_B)$ already operating q outlets of sports in the market. This algorithm selects top q nodes among $V=V{\backslash}F_B$ nodes that covers maximum nodes based on the shortest distance. Then, q nodes choose next node that has a maximum cover with inclusion-exclusion principle. At the time of same number of cardinality in q sets to pre-defined q, we select the maximum cover node set. This algorithm called by competitive algorithm. The competitive algorithm simply decides the optimal location of the outlets p=1,2,3,4 for q=5. Also, we show that the market share of competitive algorithm can be maximize.