• International Journal of Aerospace System Engineering
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• v.2 no.1
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• pp.38-42
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• 2015

This work is to propose a structural design and analysis procedure for development of the low noise 1kW class small wind turbine system which will be applicable to relatively low speed region like Korea and for the domestic use. The proposed structural configuration has a sandwich composite structure with the E-glass/Epoxy face sheets and the Urethane foam core for lightness, structural stability, low manufacturing cost and easy manufacturing process. Structural analysis including load cases, stress, deformation, buckling, vibration and fatigue life was performed using the Finite Element Method, the load spectrum analysis and Miner rule. In order to evaluate the designed structure, the structural test was carried out and its test results were compared with the estimated results. Moreover Investigation on structural safety of tower was verified through structural analysis by FEM.

• Proceedings of the Korean Society of Computer Information Conference
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• 2022.07a
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• pp.27-28
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• 2022

최근 우리나라에서도 인공지능 모델을 이용한 수온 예측 관련 연구가 활발히 진행되고 있으나 한반도 주변 해역의 수온 예측 연구에서는 주로 해수면 온도만을 예측하는데 중점을 두고 있다. 본 논문에서는 XBT(eXpendable Bathy-Thermograph) 데이터와 LightGBM(Light Gradient Boosting Model)을 이용하여 잠수함 작전 및 대잠전(Anti Submarine Warfare)에 있어서 군사적으로 중요한 동해의 수직 수온분포를 예측하였다. 동해 특정해역의 해수면부터 수심 200m까지 측정된 XBT 데이터를 이용하여 모델을 학습시키고 성능 평가지표(MAE, MSE, RMSE)와 수직 수온분포 그래프를 통해 예측 정확도를 평가하였다.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.44 no.3
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• pp.34-38
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• 2007

There has been skeptical aspects for the robot to be effective in combat fields even though consensus of operational needs and some technological advancements. One of fundamental problems is difficulties in the autonomous technology applicable. This technology is not sufficient to be applied for heavy combat operation, therefore, developer first make open architecture, then, application is implemented on the condition that new functions or technologies will be developed later. It is also required to partition all the functions with common segments which are general to all platforms in order to operate together in the fields and to reduce the load of development to each platform respectively. In addition, common middleware based on the reference architecture is also developed to accommodate new technology evolution. This paper introduces the architecture and middleware applied in XAV(eXperimental Autonomous Vehicle) developed in ADD. In addition, the performance of autonomous navigation and system design characteristics are introduced briefly.

• Journal of Intelligence and Information Systems
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• v.16 no.2
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• pp.55-72
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• 2010

Recently, the battlefield environment has changed from platform-centric warfare(PCW) which focuses on maneuvering forces into network-centric warfare(NCW) which is based on the connectivity of each asset through the warfare information system as information technology increases. In particular, C4I(Command, Control, Communication, Computer and Intelligence) system can be an important factor in achieving NCW. It is generally used to provide direction across distributed forces and status feedback from thoseforces. It can provide the important information, more quickly and in the correct format to the friendly units. And it can achieve the information superiority through SA(Situational Awareness). Most of the advanced countries have been developed and already applied these systems in military operations. Therefore, ROK forces also have been developing C4I systems such as KJCCS(Korea Joint Command Control System). And, ours are increasing the budgets in the establishment of warfare information systems. However, it is difficult to evaluate the C4I effectiveness properly by deficiency of methods. We need to develop a new combat effectiveness evaluation method that is suitable for NCW. Existing evaluation methods lay disproportionate emphasis on technical factors with leaving something to be desired in human factors. Therefore, it is necessary to consider technical and human factors to evaluate combat effectiveness. In this study, we proposed a new Combat Effectiveness evaluation algorithm called E-TechMan(A Combat Effectiveness Evaluation Algorithm Considering Technical and Human Factors in C4I System). This algorithm uses the rule of Newton's second law($F=(m{\Delta}{\upsilon})/{\Delta}t{\Rightarrow}\frac{V{\upsilon}I}{T}{\times}C$). Five factors considered in combat effectiveness evaluation are network power(M), movement velocity(v), information accuracy(I), command and control time(T) and collaboration level(C). Previous researches did not consider the value of the node and arc in evaluating the network power after the C4I system has been established. In addition, collaboration level which could be a major factor in combat effectiveness was not considered. E-TechMan algorithm is applied to JFOS-K(Joint Fire Operating System-Korea) system that can connect KJCCS of Korea armed forces with JADOCS(Joint Automated Deep Operations Coordination System) of U.S. armed forces and achieve sensor to shooter system in real time in JCS(Joint Chiefs of Staff) level. We compared the result of evaluation of Combat Effectiveness by E-TechMan with those by other algorithms(e.g., C2 Theory, Newton's second Law). We can evaluate combat effectiveness more effectively and substantially by E-TechMan algorithm. This study is meaningful because we improved the description level of reality in calculation of combat effectiveness in C4I system. Part 2 will describe the changes of war paradigm and the previous combat effectiveness evaluation methods such as C2 theory while Part 3 will explain E-TechMan algorithm specifically. Part 4 will present the application to JFOS-K and analyze the result with other algorithms. Part 5 is the conclusions provided in the final part.

• Journal of National Security and Military Science
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• s.5
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• pp.241-280
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• 2007

This study examines the relationship of the industry-specific factors that effect innovation of manufacturing technology and the market share within the defense industry. Since the establishment of the basic defense industry framework in 1973, there were numerous interactions of the industry-specific factors of the defense industry structure with the technological innovation and market organization of the defense industry. During last three decades, the domestic defense industry has achieved the considerable level but the framework of the basic system has not developed much in areas of the military science and the defense manufacturing technology. Industry-specific factors were formed in the process and appeared in a variety of behavioral characteristics as subsystems. Currently, there IS a growing trend where the management of defense industry is gradually deteriorating due to limitation of the domestic industry-specific factor (e.g. defense technologies, amount of demand, etc.). If there is a prominent imbalance of the industry-specific factors. it can trigger the potential problem of conflict, lack of cooperation and control, slowing the growth of the manufacturing technology thereby diminishing the market and deteriorating the defense supply/demand relationship. In a research conducted by Joe S. Bain, Bain analyzed the relationship of the traditional industrial organization where industry-specific factor(S) not only impacts the conductor(C). And, conductor(C) influences the shaping of the performance(P) of relationship of the traditional industrial organization. Consequently, the researcher has identified the demand monopoly, barriers to entry, and market competition with comparison of defense industry issues. These defense issues were three industry-specific factors identified, which are 1) The demand monopoly and The entry barriers to new market competition, 2) the industrial technical factor to a production technical competitiveness and a market sharing competitiveness, 3) the probability factor to revolution for military affairs(RMA) and a R&D production. According to baseline with these factors, the following research model is established from the special companies group(Group A), the systematization companies group(Group B), and the general companies group(Group 0. The hypothesis is that if there are more industry-specific factors, then there will be more relationships of defense industry relation statutes. This research is an empirical study on the relationship that the industry specific factors effects the innovation of manufacturing technology and the shaping of the market in the defense industry. Moreover, the existing models to evaluate the industry specific factors of the defense industry IS much to be desired with the controlled statistical analysis of the result. It is vital to study on current situation with suggesting alternative strategy to the efficient strategy. The descriptive analysis approach analysis is conducted with SPSSWIN to conduct reliability test, factor analysis, correlation analysis, cross-tabulation analysis, one-way ANOVA, and multiple regression analysis. However, there were some limitations of the survey such as the rigidity of concept about the technical factors and various market management factors. The wishes is that the decision-maker could be utilized these defence industrial factors to formulate efficient defence policy and strategy in the future.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.12
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• pp.265-270
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• 2019

In order to protect the advancement of defense technology that has a tremendous e?ect on both the national security and the economy, the Republic of Korea established the Defense Technology Security Act in 2015. As the new enactment brought changes to the landscape of the defense industry and defense industrial security, a new examination of the concept of the defense industrial security has now become necessary. Even after taking into consideration the undisclosed nature of defense industrial security research, and the fact that only the limited number of firms participates in the subject matter, scientific studies related to the topic have not been active. However, with the new enactment of the Defense Technology Security Act, it is necessary to expand the scope of security and to redefine the concept of defense industrial security. In this paper, we analyzed the research works on related technology protection policies and our environment of the defense industry in order to conceptualize defense industrial security. The established concepts are expected to provide a systematic way to protect the confidential and defense technology.

• The Journal of the Acoustical Society of Korea
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• v.18 no.3E
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• pp.9-20
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• 1999

To investigate the characteristics of internal waves (IWs) and their effects on acoustic wave propagation, a series of sea experiment were performed in the east coast of Donghae city, Korea in 1997 and 1998 where the water depth varies between 130 and 140 m. Thermistor strings were deployed to measure water temperatures simultaneously at 9 depths. CW source signals with the frequencies of 250,670 and 1000 Hz were received by an array of 15 hydrophones. Through the Wavelet transform analysis, the IWs are characterized as having typical periods of 2-17 min and duration of 1-2 hours. The IWs exist in a group of periods rather than in one period. Underwater acoustic signals also show obvious energy peaks in the periods of less than 12 min. Consistency in the periods of the two physical processes implies that acoustic waves react to the IWs through some mechanisms like mode interference and travel time fluctuation. Based on the thermistor string data, mode arriving structures are analyzed. As thermocline depth varies with time, it may cause travel time difference as much as 4-10 ms between mode 1 and 2 over 10 km range. This travel time difference causes interference among modes and thus fluctuation from range-independent stratified ocean structure. In real situations, however, there exist additional spatial variation of IWs. Model simulations with all modes and simple IWs show clear responses of acoustic signals to the IWs, i.e., fluctuations of amplitude and phase.

• Toxicological Research
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• v.17
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• pp.299-304
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• 2001

Xenobiotics and their reactive intermediates bind to cellular macromolecules and/or generate oxidative stress. which provoke deleterious effects on the cell function. Induction of xenobiotic-biotrans-forming enzymes and antioxidant molecules is an important defense mechanism against such insults. A group of genes involved in the defense mechanism. e.g. genes encoding glutathione S-transferases. NAD(P)H: quinone oxidoreductase, UDP-glucuronosyltransferase (UDP-GT) and ${\gamma}$-glutamylcysteine synthetase (GGCS). have a common regulatory sequence, Antioxidant or Electrophile Responsive Element (ARE/EpRE). Recently. Nrf2. discovered as a homologue of erythroid transcription factor p45 NF-E2, was shown to bind ARE/EpRE and induce the expression of these defense genes. Mice that lack Nrf2 show low basal levels of expression and/or impaired induction of these genes. which makes the animals highly sensitive to xenobiotic toxicity. Indeed. we show here that nrf2-deficient mice had a higher mortality than did the wild-type mice when exposed to acetaminophen (APAP). Detailed analyses of APAP hepatotoxicity in the nrf2 knockout mice indicate that a large amount of reactive APAP metabolites was generated in the livers due to the impaired basal expression of two detoxifying enzyme genes, UDP-GT (Ugt1a6) and GGCS. while the cytochrome P450 content was unchanged. Thus. the studies using the nrf2 knockout mice clearly demonstrate significance of the expression of Nrf2-regulated enzymes in protection against xenobiotic toxicity.

• Korean Journal of Materials Research
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• v.5 no.3
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• pp.333-344
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• 1995

Cu를 함유한 2종의 저합금 고장력강(HSLA-A, HSLA-B)\ulcorner 기계적 성질에 미치는 시효처리의 영향을 조사하였다. 탄소량이 적음에도 불구하고 Cu첨가로 석출물을 생성시킴으로서 2합금 모두 $650^{\circ}C$에서 시효한 경우 양호한 강도(HSLA-A:Y.S 703Mpa, E.L 22.6% HSLA-B:Y.S 810 Mpa, E.L 23.8%)와 인성(HSLA-A:271.4J, HSLA-B:197.5J at -5$0^{\circ}C$)의 조합을 나타내었다. 50$0^{\circ}C$에서 시효할 때 가장 높은 항복 강도를 나타내나 인성은 아주 낮은 값을 나타내었다. 50$0^{\circ}C$이상 시효 온도가 증가하면 강도는 감소하고 인성은 증가하였다. HSLA-B강의 강도가 HSLA-A 강보다 높은데, \ulcorner칭 상태에서의 강도 차이는 경화능을 증가시키는 원소인 Ni, Mn, Mo, Cu의 첨가량 차이에 의한 기지 조직의 차이에 의한 것이며, 시효한 상태에서의 강도 차이는 기지 조직과 석출 강화에 기여하는 Cu량의 차이에 의한 것으로 판단된다. 시효 경화 곡선에서 $700^{\circ}C$에서의 경도 증가는 오스테나이트-페라이트 2상 영역으로부터 냉각시 생성된 “M-A constituents”에 의한 것이다. HSLA-A강과 HSLA-B강의 충격 천이 온도는 각각 -1$25^{\circ}C$와 -145$^{\circ}C$이었다.

• The Plant Pathology Journal
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• v.39 no.1
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• pp.28-38
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• 2023

Plant viruses are responsible for worldwide production losses of numerous economically important crops. The most common plant RNA viruses are positivesense single-stranded RNA viruses [(+)ss RNA viruses]. These viruses have small genomes that encode a limited number of proteins. The viruses depend on their host's machinery for the replication of their RNA genome, assembly, movement, and attraction to the vectors for dispersal. Recently researchers have reported that chloroplast proteins are crucial for replicating (+)ss plant RNA viruses. Some chloroplast proteins, including translation initiation factor [eIF(iso)4E] and 75 DEAD-box RNA helicase RH8, help viruses fulfill their infection cycle in plants. In contrast, other chloroplast proteins such as PAP2.1, PSaC, and ATPsyn-α play active roles in plant defense against viruses. This is also consistent with the idea that reactive oxygen species, salicylic acid, jasmonic acid, and abscisic acid are produced in chloroplast. However, knowledge of molecular mechanisms and functions underlying these chloroplast host factors during the virus infection is still scarce and remains largely unknown. Our review briefly summarizes the latest knowledge regarding the possible role of chloroplast in plant virus replication, emphasizing chloroplast-related proteins. We have highlighted current advances regarding chloroplast-related proteins' role in replicating plant (+)ss RNA viruses.