• Title/Summary/Keyword: strength of security

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A Study on the Finite Element Analysis and Management Criteria by Applying UPRS Method in the Subway Station (기존 지하철정거장 비개착공법 적용시 유한요소 해석과 관리기준에 관한 연구)

  • Cho, Byeong Joon
    • Journal of Korean Society of Disaster and Security
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    • v.12 no.4
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    • pp.43-52
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    • 2019
  • To analyze the influence on the stability, resulting from application of upgrade pipe roof structure (UPRS) method to the structure existed under subway Station, physical properties of a ground, elasticity and elasto-plastic theories, including displacement analysis of finite elements, stress analysis of finite elements, displacement caused by steel pipe propulsion and internal excavation, and stress change in a steel pipe, were introduced. Then, the influence on structural stability when applying the UPRS method was compared and reviewed based on the construction management standard of the Ministry Land, Infrastructure and Transport and foreign sources, using numerical analysis with a model which assumes that each microelement divided into a structurally stable point consists of the connection of finite points. As a result of the finite element analysis, 7.21 mm maximum displacement, 1/3,950 angular displacement, 70.28 MPa bending compressive stress of steel pipe structure constructed with UPRS (non-excavation) method and 477.38 MPa maximum shear strength were within their allowable standards (25.00 mm, 1/500, 210.00 MPa and 120.00 MPa, respectively), and therefore, the results showed that the design and construction are stable.

A Study of the Future Terrorism : Its Patterns and Perspectives (미래 국제 테러 유형과 전망에 관한 연구)

  • Choi, Jin-Tai
    • Korean Security Journal
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    • no.15
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    • pp.337-358
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    • 2008
  • With the Japanese attacks on Pearl Harbor in 1941, approximately 2,500 people were killed. The terrorist attack on World Trade Center in the United States resulted in the heavy loss of people's lives, 2,749 in all. The 9.11 demonstrated that terrorist attack could be more serious problem than the war in our modern life. In addition, terrorist armed with new and high technologies have become more dangerous elements to the international community. Especially, the fact that the weapons of mass destruction are used by terrorist organizations is a matter of great concern. The strength of terrorist arsenal gives terrorist a decided advantage over us. The chances of success for terrorist have been increased due to the terrorist friendly environments. Terrorism has evolved without stopping from its birth, which is imposing a great burden on the authorities concerned. The counter-terrorism strategy and tactics used in the past have been useless in the fighting against new terrorism. To cope with the fast changing terrorism, comprehensive countermeasures should be developed. The purpose of this study is to know the enemy. To achieve the goal, the current situation on international terrorism as a whole is examined. Based on the result of the research, this paper also tried to give a perspectives on the future terrorism. At the same time, it provides a guidelines of the direction in the fighting against terrorism.

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Video Watermarking Scheme with Adaptive Embedding in 3D-DCT domain (3D-DCT 계수를 적응적으로 이용한 비디오 워터마킹)

  • Park Hyun;Han Ji-Seok;Moon Young-Shik
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.15 no.3
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    • pp.3-12
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    • 2005
  • This paper introduces a 3D perceptual model based on JND(Just Noticeable Difference) and proposes a video watermarking scheme which is perceptual approach of adaptive embedding in 3D-DCT domain. Videos are composed of consecutive frames with many similar adjacent frames. If a watermark is embedded in the period of similar frames with little motion, it can be easily noticed by human eyes. Therefore, for the transparency the watermark should be embedded into some places where motions exist and for the robustness its magnitude needs to be adjusted properly. For the transparency and the robustness, watermark based on 3D perceptual model is utilized. That is. the sensitivities from the 3D-DCT quantization are derived based on 3D perceptual model, and the sensitivities of the regions having more local motion than global motion are adjusted. Then the watermark is embedded into visually significant coefficients in proportion to the strength of motion in 3D-DCT domain. Experimental results show that the proposed scheme improves the robustness to MPEG compression and temporal attacks by about $3{\sim}9\%$, compared to the existing 3D-DCT based method. In terms of PSNR, the proposed method is similar to the existing method, but JND guarantees the transparency of watermark.

A Study about The Global Trend of Neo-Grouting Technology (최신 그라우팅 기술의 세계적인 동향에 관한 연구)

  • Kim, Jin-Chun;Kim, Sang-Gyun;Yoo, Byung-Sun;Kang, Hee-Jin
    • Journal of Korean Society of Disaster and Security
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    • v.7 no.2
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    • pp.25-34
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    • 2014
  • This study researches on global technology trend in each of composing technology, such as grouting material, grouting equipment, and construction management technology, which grouting technology has been founded upon to improve relatively inadequate domestic grouting technology and to establish the global standard for overseas expansion in the future. As far as grouting material is concerned, while High-Penetration and High-Strength micro cement ($1.5{\mu}m$) has been developed in 2000's in Japan, JinChun Kim et al. (2014) has been developing hybrid type micro cement grouting material and examining specifications of different kinds of projects and countries to analyze the trend of grouting equipment development. The specification contains detailed requisite specification for materials, mixers, pumps, agitators, and packers and it has to satisfy the standard of different countries to win global contracts. Grouting management technology can be divided into four different generations and Scandinavian countries, such as Sweden, Norway, and Finland, Japan, and South Korea are recently doing vigorous researches on the Fourth generation which merges grouting technology with ICT.

A study on unmanned watch system using ubiquitous sensor network technology (유비쿼터스 센서 네트워크 기술을 활용한 무인감시체계 연구)

  • Wee, Kyoum-Bok
    • Journal of National Security and Military Science
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    • s.7
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    • pp.271-303
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    • 2009
  • "Ubiquitous sensor network" definition is this-Someone attaches electro-magnetic tag everything which needs communication between man to man, man to material and material to material(Ubiquitous). By using attached every electro-magnetic tag, someone detects it's native information as well as environmental information such as temperature, humidity, pollution and infiltration information(Sensor). someone connects it realtime network and manage generated information(Network). 21st century's war is joint combined operation connecting with ground, sea and air smoothly in digitalized war field, and is systematic war provided realtime information from sensor to shooter. So, it needs dramatic development on watch reconnaissance, command and control, pinpoint strike etc. Ubiquitous computing and network technologies are essential in national defense to operate 21st century style war. It is possible to use many parts such as USN combined smart dust and sensor network to protect friend unit as well as to watch enemy's deep area by unmanned reconnaissance, wearable computer upgrading soldier's operational ability and combat power dramatically, RFID which can be used material management as well as on time support. Especially, unmanned watch system using USN is core part to transit network centric military service and to get national defense efficiency which overcome the dilemma of national defense person resource reducing, and upgrade guard quality level, and improve combat power by normalizing guardian's bio rhythm. According to the test result of sensor network unmanned watch system, it needs more effort and time to stabilize because of low USN technology maturity and using maturity. In the future, USN unmanned watch system project must be decided the application scope such as application area and starting point by evaluating technology maturity and using maturity. And when you decide application scope, you must consider not only short period goal as cost reduction, soldier decrease and guard power upgrade but also long period goal as advanced defense ability strength. You must build basic infra in advance such as light cable network, frequency allocation and power facility etc. First of all, it must get budget guarantee and driving force for USN unmanned watch system project related to defense policy. You must forwarded the USN project assuming posses of operation skill as procedure, system, standard, training in advance. Operational skill posses is come from step by step application strategy such as test phase, introduction phase, spread phase, stabilization phase and also repeated test application taking example project.

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Evaluation of the Mechanical Properties of Field-Cast Shotcrete and Long-Term Durability by Combined Deterioration Test (현장타설 숏크리트의 역학적 성능 평가 및 복합열화시험을 통한 장기내구성 평가)

  • Ma, Sang-Joon;Jang, Phil-Sung;Kim, Dong-Min;Choi, Jae-Seok
    • Journal of the Korea Concrete Institute
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    • v.19 no.1
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    • pp.47-56
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    • 2007
  • Recently, tunnels are increasingly constructed in this country with the increased construction of highways, high-speed railways and subways. Shotcrete is one of the major processes in the tunnel construction. Many problems, however, exist in the current shotcrete practice. The purpose of the study is, therefore, to explore the trobles in the current shotcreting practice, and to develop high-quality silica fume shotcrete. For the purpose of security a long-term durability of shotcrete, this study conducted combined deterioration tests. In this study, a combined deterioration test in consideration of a variety of deterioration factors were proceeded. Especially, micro-silica fume that was used frequently in overseas because of a outstanding strength-promotion effect was applied to combined deterioration test, and a long-term durability of shotcrete was investigated according to additions mixing. As a result of test, the shotcrete mixed Micro-silica fume showed a good deterioration quality compared with the other mixes. And is shows that the Micro-silica fume has an outstanding strength-promotion effect and is effective to secure a long-term durability of shotcrete by means of decreasing a deterioration caused by steel fiber mixed.

Impact response of a novel flat steel-concrete-corrugated steel panel

  • Lu, Jingyi;Wang, Yonghui;Zhai, Ximei;Zhou, Hongyuan
    • Steel and Composite Structures
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    • v.42 no.2
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    • pp.277-288
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    • 2022
  • A novel flat steel plate-concrete-corrugated steel plate (FS-C-CS) sandwich panel was proposed for resisting impact load. The failure mode, impact force and displacement response of the FS-C-CS panel under impact loading were studied via drop-weight impact tests. The combined global flexure and local indentation deformation mode of the FS-C-CS panel was observed, and three stages of impact process were identified. Moreover, the effects of corrugated plate height and steel plate thickness on the impact responses of the FS-C-CS panels were quantitatively analysed, and the impact resistant performance of the FS-C-CS panel was found to be generally improved on increasing corrugated plate height and thickness in terms of smaller deformation as well as larger impact force and post-peak mean force. The Finite Element (FE) model of the FS-C-CS panel under impact loading was established to predict its dynamic response and further reveal its failure mode and impact energy dissipation mechanism. The numerical results indicated that the concrete core and corrugated steel plate dissipated the majority of impact energy. In addition, employing end plates and high strength bolts as shear connectors could prevent the slip between steel plates and concrete core and assure the full composite action of the FS-C-CS panel.

A Theoretical Analysis of International Civil Aviation Organization (국제민간항공기구의 이론적 고찰)

  • Kim, Kwan-Ok
    • The Korean Journal of Air & Space Law and Policy
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    • v.14
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    • pp.151-174
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    • 2001
  • Theories of international organization have explained the creation, maintenance, and decline of international organization. However, their explanations on changes of international organization have been much more different one another. For example, the theory of hegemonic stability argues that international organization can be created and maintained only by a hegemonic state and will be declined if the hegemonic state decline. On the other hand, the functional approach believes that the positive functions and effects that international organization provides motivate states to create and maintain the organization, while the game-theoretical approach explains international organization based on cost-benefit calculation of rational states. Thus, the empirical evaluation of the arguments of the theories of international organization and defining the major factors that determine international organization are necessary not only for the development of theories of international organization but also for making desirable policies toward international organization. For the purpose, this paper compares and contrasts the three major theories of international organization and applies the approaches to the case of the International Civil Aviation Organization (ICAO) to test their arguments. Since the ICAO has been rarely examined by the theories of international organization, the case study could be desirable case to evaluate theories of international organization. In this sense, this paper attempts to define the major factors that determine the creation, maintenance, and decline of the ICAO. In particular, since the Korean government has changed its policy for air transport security system recently, it will investigate the role of ICAO on the policy change to define the limits and strength of ICAO. In conclusion, this paper will assess the relative explanatory power of each approach based on the analysis of the creation and changes of ICAO

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Psychology of Young Adulthood (청년기심리 (靑年期心理))

  • Cho, Doo-Young
    • Korean Journal of Psychosomatic Medicine
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    • v.5 no.2
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    • pp.223-236
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    • 1997
  • One faces four major developmental tasks to achieve in young adulthood, ages between 20 and 40 : intimacy, vocation, marriage and child-rearing. Intimacy is the capacity to commit oneself to concrete affiliations and partnerships and to develop the ethical strength to abide by such commitments, even though they call for significant sacrifices and compromises. Through vocation and marriage young adults become united to networks of persons, find tasks that demand involvement, and gain roles into which they fit and are fitted and which help define their identities. An occupation represents much more than a set of skills and functions : it means a way of life. The extent of vocational choice increases with educational level, and the unconscious factors are frequency the decisive element. The vocational choice stare with fantasy choices in childhood, passes through tentative choices in adolescence, realistic choices in college days, and crystallized choices in post-college days, and finally ends up to the choice of specification. Along with the hazards and the need for realignment of personality functioning, the marriage brings with it new opportunities for self-fulfillment and completion. Motives other than a romantic love gain more importance in the decision to marry and in the choice of a partner. The impulsions to marry are sexual gratification, the desire to propagate, narcissistic gratification, and a need of interdependence. Many factors such as oedipal wishes, sexuality and sexual attractions, socio-economic classes, and geography involve in selection of marriage partner. There are also various motivations to marry a romantic love, the desire for a home of one's own, sexual attractions, the wish for security and a shelter, and the wish for children. The hostile marriage, the marriage on the rebound, the marriage rooted in rescue fantasies, and sado-masochistic marriage are the examples of pathological marriages. A successful marriage will usually both Lead to and require a marked reorganization of the personality structure of each partner that will influence the lurker personality development of each. Many marital problems are largely dependent upon the personality characteristics of one partner which might well create difficulties no manor who was the spouse.

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A Study on the Cases of Merchandising and Suggestions for Improving Competitive Power of Traditional Liquor (전통주류 상품화 사례 및 경쟁력 제고 방안 연구)

  • Jun Young-Mi;Ahn Yoon-Su;Kim Mi-Hee
    • The Korean Journal of Community Living Science
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    • v.17 no.2
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    • pp.3-14
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    • 2006
  • This study intends to offer suggestions for improving the security and competitive power of traditional liquors by investing in the status of intellectual property rights. Merchandising and the marketing strategies of traditional liquor are also addressed. The data was collected through a questionnaire survey given to 101 CEOs of traditional liquor manufacturers. The major results of this study were as follows: The management types of traditional liquor manufacturers were classified as the company 57 (56.4%), the corporation or the union 29 (28.7%), domestic industry 10 (9.9%), and marketing community or technology center 5 (5.0%). The competitive power degree of traditional liquor products was classified as strength 30 (31.6%), usual 30 (31.6%), weakness 35 (36.8%). The elements of strong competitive power were taste, functional (wellbeing) character, and attractiveness of the brand name. On the other side, reasons for weakness in competitive power were the marketing system, price competitiveness, and advertisement. The trademark registration of the traditional liquor appeared with 53%. The reasons not to pursue a trademark registration included the complicated and unnecessary process of registration acquisition, high registration expenses, etc. The perceptions of CEOs about the consumer's brand awareness for their product were low with an average 2.97. Explanations included insufficient advertisement and public relations, unrefined trademark design, and the meaninglessness of brand names. The marketing strategy of traditional liquor manufacturers according to annual sales were as follows: Manufacturers with high sales emphasized marketing strategies that focused on functional character, traditional image, high quality in image and package materials and design, high price strategies based on quality, and various sale promotions.

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