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A Research on the Nuclear Deterrence Strategy of South Korea through Dispute of India and Pakistan

  • Dong-Kwon Cho;Young-Hwan Ryu;Sin-Young Yu
    • 방사선산업학회지
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    • 제17권4호
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    • pp.411-416
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    • 2023
  • From Cold War, Nuclear weapons have emerged military power into a very dangerous and important way of each national security. Throughout the era, the U.S. had stationed nuclear weapons in South Korea. But President George Bush initially started the withdrawal of nuclear tactical weapons deployed abroad in 1991. After that, under the protection of the nuclear umbrella, South Korea guarantees that the United States would operate its nuclear weapons to protect South Korea if it would be needed and the economy of South Korea has rapidly developed as more strong countries in the world. However, South Korea has seen and been realized the present state from the recent war between Russia and Ukraine. The protection of the U.S. nuclear umbrella from nuclear weapons and ballistic missiles of North Korea is unlikely to be permanently guaranteed. At the same time, South Korea should consider the security environment changes of surrounding nations such as China as military power acceleration and Russia as re-formation ambition. Because of these reasons, South Korea independently wants to protect itself and have the own nuclear weapons as a way to counter security threats. A majority of South Koreans also definitely believe that North Korea will not denuclearize or give up because North Korea has been having nuclear weapons as the final survival strategy of Kim Jong Un's regime. However, South Korea considers and makes new nuclear strategy through the role and effect of nuclear deterrence strategy in dispute between India and Pakistan and how to overcome the paradox of nuclear deterrence strategy. Therefore, this research is to suggest the effective nuclear deterrence strategy of South Korea from new security threats of surrounding nations through dispute between India and Pakistan. The focus of this research is that what is the role and paradox of nuclear deterrence strategy in dispute between India and Pakistan and how to find the effective nuclear deterrence strategy of South Korea.

UAM 효과 평가를 위한 현장실험 및 정량적 2차원 수치해석기법 개발에 관한 연구 (A study on the field tests and development of quantitative two-dimensional numerical analysis method for evaluation of effects of umbrella arch method)

  • 김대영;이홍성;천병식;정종주
    • 한국터널지하공간학회 논문집
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    • 제11권1호
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    • pp.57-70
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    • 2009
  • UAM(Umbrella Arch Method)의 효과 및 역학적 보강메커니즘에 대한 연구는 국내외에서 수치해석 및 실험 등을 통하여 상당한 진척이 이루어졌으나 실제 설계 및 적용에 있어서는 아직도 3차원 해석의 해석시간과 복잡성 등의 제약 때문에 UAM의 보강영역과 지반과의 환산물성을 이용하는 정량적이지 못한 2차원해석이 주로 사용되고 있다. 이러한 이유로 합리적, 이론적, 정량적이면서도 손쉽게 수행할 수 있는 설계 및 해석기법이 요구되고 있다. 본 연구에서는 UAM의 보강효과가 미치는 범위를 파악하고 그라우팅 전 후의 강관저변지반 물성변화를 파악하기 위하여 연직방향의 UAM 현장실험 및 실내시험을 수행하였다. 풍화토, 풍화암 지반에 UAM 적용시 그라우트의 주입에 의한 주변지반의 물성치 증가는 미미하며, 강관외부와 천공구경 사이의 공간 및 강관내부에 형성된 시멘트구근과 강관으 강성만이 지반보강 효과에 기여한다는 것을 확인하였다. 이러한 결과와 내공변위제어법(CCM; Convergence Confinement Method) 개념을 바탕으로, 2차원 축대칭해석을 실시하여 막장효과, UAM효과와 지보재효과를 종단변위곡선(LDP)으로 나타내었다. 또한, 2차원 평면변형률 해석시 UAM의 지보효과를 내압의 크기로 변환하여 이를 고려하는 하중분담법을 제안하였다. 이 방법과 기존의 등가환산물성을 적용하는 해석을 비교한 결과, 지반조건, 터널의 심도 및 크기, 강관조건, 초기응력상태 등에 따라 차이가 있지만, 기존의 해석방법에서의 변위량이 새로운 방법에 비해 더 크게 발생하는 것으로 나타나, UAM의 종방향 빔 지지효과를 제대로 평가하지 못하는 것으로 나타났다.

A Minimalist Model of Single Molecule Spectroscopy in a Dynamic Environment Studied by Metadynamics

  • Oh, In-Rok;Lee, Eun-Sang;Jung, Youn-Joon
    • Bulletin of the Korean Chemical Society
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    • 제33권3호
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    • pp.980-986
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    • 2012
  • In this paper we develop a minimalist model of single molecule spectroscopy in a dynamic environment. Our model is based upon a lattice system consisting of a probe molecule embedded in an Ising-model like environment. We assume that the probe molecule interacts with the Ising spins via a dipole-dipole potential, and calculate free energy curves and lineshapes of the system. To investigate fluctuation behavior of the system we exploit the metadynamics sampling method. In particular, using the method, we calculate the free energy curve of magnetization of the lattice and that of the transition energy of the probe molecule. Furthermore, we compare efficiencies of three different sampling methods used; unbiased, umbrella, and metadynamics sampling methods. Finally, we explore the lineshape behavior of the probe molecule as the system undergoes a phase transition from a sub-critical and to a super-critical temperature. We show that the transition energy of a probe molecule is broadly distributed due to the heterogeneous, local environments.

How to approach feeding difficulties in young children

  • Yang, Hye Ran
    • Clinical and Experimental Pediatrics
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    • 제60권12호
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    • pp.379-384
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    • 2017
  • Feeding is an interaction between a child and caregiver, and feeding difficulty is an umbrella term encompassing all feeding problems, regardless of etiology, severity, or consequences, while feeding disorder refers to an inability or refusal to eat sufficient quantities or variety of food to maintain adequate nutritional status, leading to substantial consequences, including malnutrition, impaired growth, and possible neurocognitive dysfunction. There are 6 representative feeding disorder subtypes in young children: infantile anorexia, sensory food aversion, reciprocity, posttraumatic type, state regulation, and feeding disorders associated with concurrent medical conditions. Most feeding difficulties are nonorganic and without any underlying medical condition, but organic causes should also be excluded from the beginning, through thorough history taking and physical examination, based on red-flag symptoms and signs. Age-appropriate feeding principles may support effective treatment of feeding difficulties in practice, and systematic approaches for feeding difficulties in young children, based on each subtype, may be beneficial.

통합 제품-서비스로의 이행: 문헌 연구, 분류 체계, 연구 방향

  • 박용태;이학연;한우리;설현주
    • 기술경영경제학회:학술대회논문집
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    • 기술경영경제학회 2009년도 동계학술발표회
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    • pp.583-604
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    • 2009
  • 최근 제조 기업들의 가장 큰 화두 중 하나는 제품과 서비스의 통합이다. 그간 제품과 서비스 통합과 관련한 다양한 개념들이 제시되어 왔으나, 정의 및 유형에 대한 보편적인 프레임워크가 존재하지 않는다. 본 연구에서는 제품과 서비스의 통합에 관련된 다양한 개념들을 아우르는 포괄적인 용어 (umbrella term)로써 통합 제품-서비스(integrated product-service: IPS)를 제시한다. 기존 문헌 연구를 통해 IPS 관련 기존 개념들을 개괄하고, 이들을 Product/service fusion과 Product/service Convergence의 두 가지로 분류한다. 다음으로 IPS를 유형화하기 위한 분류체계(typology)로써 IPS 큐브(cube)를 제시한다. IPS 큐브는 통합의 형태(pattern), 원천(origin), 기술(technology)의 세 가지 차원으로 구성되며, 각 차원이 모두 세 가지 유형으로 구분되기 때문에, IPS 큐브는 27개의 셀로 이루어진 정육면체 형태를 띤다. 각 셀은 고유한 IPS 유형을 나타내며, 각 셀에 해당하는 실제 IPS 사례들이 제시된다. 본 연구에서 제시한 IPS 큐브는 유형별 IPS 개발을 위한 전략, 프로세스, 방법론을 개발하는데 있어서 유용한 시사점을 제공해줄 수 있다.

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브랜드 아이덴티티 강화를 위한 제약회사 패키지디자인 개선방안 모색 (Pharmaceutical Companies to Enhance Brand Identity and Package Design for the Improvement)

  • 진정오;백경덕
    • 한국산학기술학회:학술대회논문집
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    • 한국산학기술학회 2011년도 춘계학술논문집 2부
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    • pp.996-999
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    • 2011
  • 패키지디자인은 상품이 다양화 되고 선택의 기회와 폭이 넓어지면서 소비자는 감성적 가치에 치중하게 되었다. 본 연구는 건강식품브랜드 패키지디자인 개발을 통하여 제약회사 패키지 개발의 특수성과 제작에 있어서 개선방안을 모색하고자 하였다. 연구대상인 제약회사 패키지 디자인은 첫째, 엄브렐러 브랜드(umbrella brand) 정책을 실시하고 있었다. 둘째, 보령 수앤수(보령 건강식품브랜드)의 브랜드 아이덴티티 부재이다. 셋째, 패키지 디자인에있어 규제가 많아서 시각적으로 보기 좋은 패키지 디자인을 하기 어려운 부분이 있다. 제약회사는 규모와 투자여력에 비하여 패키지 디자인에 투자하지 않는 영세성의 문제점을 가지고 있다. 국제적인 제약회사가 패키지 디자인에 강력한 시각적 아이덴티티 정책을 실시하고 있음을 양지하고 이를 개선하는 방안을 모색해야 한다.

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A Study on the Internal Structure of Heumgyeonggaknu

  • Kim, Sang Hyuk;Lee, Yong Sam;Lee, Min Soo;Ham, Sun Young
    • Journal of Astronomy and Space Sciences
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    • 제30권2호
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    • pp.113-121
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    • 2013
  • Heumgyeonggaknu is a water-hammering type automatic water clock which was made by Jang Yeong-Sil in 1438. The water clock that is located in Heumgyeonggaknu consists of Suho which is equipped with 2-stage overflow. Constant water wheel power is generated by supplying a fixed amount of water of Suho to Sususang, and this power is transferred to each floor at the same time. The 1st floor rotation wheel of Gasan consists of the operation structure which has the shape of umbrella ribs. The 2nd floor rotation wheel is made so that the 12 hour signal, Gyeong-Jeom signal, and Jujeon constitute a systematic configuration. The 3rd floor rotation wheel is made so that the signal and rotation of Ongnyeo and four gods can be accomplished. Based on the above conceptual design, this paper analyzed the internal signal generation and power transmission of Heumgyeonggaknu.

풍차형 초음파 전동기 고정자의 공전 및 전동 속도 특성 (Resonance & Vibration Velocity Characteristics of the Wind-mill type Stator of Ultrasonic Motor)

  • 박만주;김영균;김진수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 추계학술대회 논문집
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    • pp.231-234
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    • 1998
  • In this study, the wind-mill type ultrasonic motor was fabricated, and then resonant frequency and vibration velocity characteristics of the stator were measured. Brass metal was pressed with umbrella-type using metal mold, then slot of 4 kind was processed in each of thickness. Among sixteen's stators, resonant frequency on vibration velocity was decreased remarkably in stator of higher resonant point, but resonant frequency on vibration velocity wasn't almost changed at lower resonant point of stator. The thickener thickness of elastic body, vibration velocity was decreased. The more slot of elastic body, vibration velocity was increased Applied voltage was changed from 10$V_{max}$ to 100$V_{max}$. Maximum vibration velocity value was 2.0[m/s].

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압전 초음파 전동기의 고정자 구조에 따른 회전 특성 (Revolution Characteristics of Piezoelectric Ultrasonic Motor with Stator Configuration)

  • 박만주;김진수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 추계학술대회 논문집 학회본부 C
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    • pp.749-751
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    • 1998
  • In this study, the wind-mill type ultrasonic motor was fabricated, and then revolution and temperature characteristics of the ultrasonic motor were measured. Brass metal was pressed with umbrella-type using metal mold, then slot of 4 kind was processed in each of thickness. Among sixteen's ultrasonic motors, heat loss on applied voltage was much at stator of the highest resonant point, but heat loss on applied voltage was almost neglected at the lowest resonant point of stator. The thickener thickness of elastic body, revolution speed was decreased. The more slot of elastic body, revolution speed was increased. Applied voltage was changed from $10V_{max}$ to $100V_{max}$. When applied voltage was under $20V_{max}$, ultrasonic motor was not rotated. When applied voltage was over $90V_{max}$, revolution of ultrasonic motor was saturated. Maximum revolution speed was 510[rpm].

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경관생태학의 개념, 원리 및 식생조사와의 관계 (Landscape Ecology Concept, Principles and Its Rlation to Monothematic (e.g. Vegetation) Survey)

  • Isaak, S. Zonneveld
    • The Korean Journal of Ecology
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    • 제21권4호
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    • pp.357-372
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    • 1998
  • Land (scape) ecology is a trans-disciplinary science studying the related systems at the earth surface, in their visual, structural and functional aspects. it serves as an umbrella under which abiotic and biotic sciences, in an integrated way, study the for each relevant land attributes and their interrelations. The spatial aspects of these relations have a special interest. Landscape ecology my have a pure scientific purpose, but usually is executed in an applied context, related to land evaluation for land use and conservation. Depending on the aim and application of the study, one of the land attributes may get special attention. Vegetation mapping may contribute to landscape ecological study but also benefit from it especially in case of reconnaissance surveys. This is because in less detailed surveys of any land attribute, like land form, soil, vegetation, one must necessarily apply landscape ecological principles in the survey methodology, including remote sensing.

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