• Title/Summary/Keyword: Air-core

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Design and Fabrication of Digital 3-axis Magnetometer for Magnetic Signal from Warship (함정 자기신호 측정용 3-축 디지털 자기센서 설계 및 제작에 관한 연구)

  • Kim, Eunae;Son, Derac
    • Journal of the Korean Magnetics Society
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    • v.24 no.4
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    • pp.123-127
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    • 2014
  • We developed a digital 3-axis flux-gate magnetometer for magnetic field signal measurement from warship during demagnetizing and degaussing processes. For the magnetometer design, we considered following points; the distance between magnetic field measurement station and magnetometer located under sea is about several 100 m, the magnetometer is exposed to magnetic field of ${\pm}1mT$ during demagnetizing process, and magnetometer is located under the sea about 30 m depth. To overcome long distance problem, magnetometer could be operated on wide input supply voltage range of 16~36 V using DC/DC converter, and for the data communication between the magnetometer and measurement station a RS422 serial interface was employed. To improve perming effect due to the ${\pm}1mT$ during demagnetizing process, magnetometer could be compensated external magnetic field up to ${\pm}1mT$ but magnetic field measuring rang is only ${\pm}100{\mu}T$. The perming effect was about ${\pm}2nT$ under ${\pm}1mT$ external magnetic field. The magnetometer was tested water vessel with air pressure up to 6 bar for the sea water pressure problems. Linearity of the magnetometer was better than 0.01 % in the measuring range of ${\pm}0.1mT$ and noise level was $30pT/\sqrt{Hz}$ at 1 Hz.

Photochemical Ozone Research in Korea - Present Status, Problems and Tasks (우리나라 광화학 오존 연구의 현황과 문제점, 과제)

  • 김영성;김용표
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 1998.10a
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    • pp.83-92
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    • 1998
  • 오존 경보제와 예보제의 실시가 오존 오염에 관한 일반인의 관심을 증폭시키는 중요한 계기가 되었음에도 우리 연구계와 정책 당국의 대응은 이에 훨씬 못미치고 있다. 1990년 이래 학회지 관련 논문 편수는 연간 1∼3편에 그치고 있고, 다른 이차오염 현상과 달리 정책 당국은 여전히 지원을 고려하지 않고 있다. 오존 연구가 뿌리를 내리지 못한 가운데 강행된 경보제와 예보제의 와중에 책임을 떠맡은 지방자치단체는 조급하게 노련한 예보 모델을 찾고 있고 충분한 검토도 없이 외국의 사례에서 대책을 구하고 있다. 논란이 되고 있는 오존 예보의 부정확성은 모델 선택의 문제가 아니라 모델 이용이 잘못된 때문이다. 현재 오존 대책의 일환으로 검토되고 있는 차량 부제 실시와 같은 단기 대책은 역효과를 낼 수 있다는 연구결과도 있다. 선진국의 오존 연구는 도시 규모에서 지역 규모로 확대되고 있고, 구츰 등 액상반응의 효과 규명과 1 kin 이하 미세 변화 모델링이 시도되고 있고, 지구 단위 대류권 실험의 일환으로 태평양 상공의 오존과 오존 전구물질의 대기화학이 조사되고 있다. 우리는 우선 우리의 오존 문제를 정확히 이해하도록 노력하여야 한다 합리적 계획 아래 체계적으로 접근하여 갈 때 당장은 아니지만 우리의 오존에 대한 이해가 깊어갈수록 예보의 정확성은 향상될 수 있다. 많은 비용과 노력이 필요한 오존 대책의 시행은 충분히 신중하여야 한다. 서울과 같은 대도시라면 적합한 수치모델을 구비하여 효과를 점검할 수 있어야 한다. 일부에서는 예보의 정확성을 높일 수 있는 방안의 하나로 수치모델 이용을 거론하고 있으나 수치모델은 매일의 예보와 같이 일상적 목적을 위하여 사용될 수 있는 모델이 아니며, 현재와 같이 기초가 갖추어져 있지 않은 상황에서는 더욱 그러하다. 정상적 모델 이용이 가능할 수 있도록 배출원 자료 체계를 갖추어야 하고, 서을 등 특징적 지역에 대하여서는 집중적 현장 조사를 실시하여야 한다.3)와 NAS(National Academy of Sciences, 1983), 미국에서 발행되는 정부 지침서 (Federal Register)에 고시된 내용 등을 토대로 하였다. 연구는 당면현실로 다가온 정보화 및 세계화의 기업환경에서 예견되는 몰입(committment)의 약화에 대한 치유방안으로서, 정보화된 경영모의게임의 기업 교육훈련 시스템(Business Training System)으로의 발전 가능성을 제시한다 하겠다.암시하며, 따라서 우리 교육문화에 맞는 재택수업 형태의 개발이 시급함을 제시한다고 하겠다.column density of HCaN is (1-3):n1014cm-2. Column density at distant position from MD5 is larger than that in the (:entral region. We have deduced that this hot-core has a mass of 10sR1 which i:s about an order of magnitude larger those obtained by previous studies.previous studies.업순서들의 상관관계를 고려하여 보다 개선된 해를 구하기 위한 연구가 요구된다. 또한, 준비작업비용을 발생시키는 작업장의 작업순서결정에 대해서도 연구를 행하여, 보완작업비용과 준비비용을 고려한 GMMAL 작업순서문제를 해결하기 위한 연구가 수행되어야 할 것이다.로 이루어 져야 할 것이다.태를 보다 효율적으로 증진시킬 수 있는 대안이 마련되어져야 한다고 사료된다.$\ulcorner$순응$\lrcorner$의 범위를 벗어나지 않는다. 그렇기 때문에도 $\ulcorner$순응$\lrcorner$$\ulcorner$표현$\lrcorner$의 성격과 형태를 외형상으로 더욱이 공간

Removal of Volatile Organic Compounds (VOCs) of Deodorant by Adding a Metal Oxide to the Essential Oils (식물정유물질에 금속산화물을 첨가한 탈취제의 휘발성유기화합물질의 제거에 관한 연구)

  • Lim, You-Young;Lee, Min-Ho;Jeon, Soo-Bin;Yang, Kyeong-Soon;Jeong, Hae-Eun;Oh, Kwang-Joong
    • Clean Technology
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    • v.22 no.2
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    • pp.96-105
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    • 2016
  • VOCs emissions from industries cause the air pollution and odor. In the industrial facilities, the existing odor treatment techniques have limits and problems. In this study, the optimum essential oil and metal oxide selected by screening test. lavender oil, cypress oil and TiO2 were determined by deodorant materials and those were blended by 5%, 45%, 10%, respectively. In addition, the result of batch type experiments depending on the dilution rate, injection, rate, temperature showed that the optimum condition of deodorant is 6 mL of injection rate, and 200 times of dilution rate and the removal efficiency increased in proportion with temperature. In addition, the activation energy was calculated from the rate equation, which appeared in the 3-4 times lower than conventional deodorants.

A Case Study on the Creating Artificial Planting Ground on the Waste Landfill Sites -In Case of the Bank Isolated Section Planting Layer at the Landfills of Satellite Cities of Seoul- (폐기물매립지 인공식재지반 조성 사례연구 -수도권매립지 제방이격구간 식재층을 대상으로-)

  • 조주형;이재근
    • Journal of the Korean Institute of Landscape Architecture
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    • v.29 no.1
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    • pp.131-139
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    • 2001
  • This paper aims at surveying through case studies the planting possibility on the interval artificial ground between the bank and the core landfill of the first section of works in the SUDOKWON Landfill area landfill area which was completed, followed by the layer-on-layer landfill process involving the latch or sealing layer against emitting landfill gas from the reclaimed waste. The survey results are as follows; 1. The layers of the artificial planting ground on the landfill were established on the basis of top-on-top procedure for a waste layer, a topping soil layer (T=50cm), a gas blocking layer (broken stones T=30cm), a filter layer (non-woven fabric 700g), a sheet protecting soil layer (T=20cm), and a blocking layer (HDPE SHEET 2.0mm), an irrigation layer (SAND T=30cm), a filter layer (non-woven fabric 700g), a sheet protecting soil layer (T=20cm), and a blocking layer (HDPE SHEET 2.0mm), an irrigation layer (SAND T=30cm), a filter layer (non-woven fabric 700g), a planting layer (T=90cm+), a top mound (T=2m). 2. Since no direct damage on the planting layer affected by the landfill gas was detected, planting is found to be still possible and successful except the severely unequal subsidence portion. 3. The mortality rate is discovered different on different trees: Pinus thunbergii (H3.0$\times$W1.0m) 11.25%, Pinus thunbergii (H2.5$\times$W0.8m) 4.73%, Koelreuteira paniculata 8.67%, Hibiscus syriacus 5.68%, Deutzia parviflora 6.50%, Forsythia koreana 8.17%, Rho. yedoense v. poukhanese 32.22%, and Spiraea pru v. symplicifolia 18.89%; although the last two of which are generally considered to have a strong generic growing character, they are subject to be weakened when exposed to the contaminated microclimate of the site like landfill gas. 4. The damage rates, on Pinus thunbergii, Koelreuteria paniculata, Hibiscus syracus, Forsythia koreana, Deutzia parviflora, Rho. yedoense v. poukhanense were shown to decrease to 7.31-17.69% in the second check (June 2000) lower than 5.77-46.92% in the first examination (June 1999), whereas the damage on Spiraea pru v. symplicifolia relatively increased. It is believed that preparatory method of the air pollution, change of temperature, odor by emitting landfill gas, and minute dust from vehicles should be made, and a research on this matter will be conducted in the near future.

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Effects of the Organizational Culture Types of Airline Members on the Effectiveness of Organizational Work: Focusing on the Mediating Effect of Knowledge Sharing (항공사 구성원의 조직문화 유형이 조직업무 효과성에 미치는 영향: 지식공유의 매개효과를 중심으로)

  • Lee, Jung-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.8
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    • pp.594-603
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    • 2019
  • This purpose of this study is for an Airline company to discover and utilize new knowledge because knowledge and information are considered core tools for achieving high performance and competitive advantage, and achieving high performance and competitive advantage will surely determine the long-term survival of airline companies. Therefore, this study aims to reveal the causal relationships among different types of organizational culture, the knowledge sharing activities and the effectiveness of organizational work by airline members from a holistic viewpoint. The results of analysis are as follows. First, when examining the effects of the organizational culture types of airline members on knowledge sharing, a creative innovation culture, a relational group culture and a hierarchical orientation culture all showed positive effects on knowledge sharing. Second, the knowledge sharing by airline members showed a significant positive effect on the effectiveness of organizational work. Third, the creative innovation culture, the relational group culture and the hierarchical orientation culture all showed positive effects on the effectiveness of organizational work. Fourth, knowledge sharing did not have a mediating effect on the relationship between organizational culture and the effectiveness of organizational work.

A Study on the Balance of Power and Changes in Military Strength in Northeast Asia: Prospect of the Northeast Asian Security Environment in 2030 Based on the Balance of Power Theory (동북아시아의 세력균형과 군사력 수준 변화 연구: 세력균형이론에 기초한 2030년경의 동북아시아 안보환경 전망)

  • Kim, Myung-soo
    • Maritime Security
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    • v.3 no.1
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    • pp.73-114
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    • 2021
  • This study examines the distribution of power in Northeast Asia based on the balance of power theory, a representative theory of realism, assuming military capabilities as the core power of states. The results of previous studies on the balance of power and military forces are reviewed and used to analyze changes in the strength of the US, China, Russia, Japan, South Korea, and North Korea through 2020 to predict the security environment in 2030. In the balance of power theory, if the balance of power between a nation or a group of powers collapses, the possibility of war is high, and to survive in the international community with high uncertainty and distrust, the theory predicts that states must increase their powers in a self-help world and strengthen cooperation and alliance. Countries in Northeast Asia are also continuing to strengthen their military capabilities, and countries neighboring China are paying keen attention and remaining vigilant due to the rapid changes in the international security environment after the rapid rise of China. To mark the future 100th anniversary of the Chinese armed forces in the 2030s, China aims to realize 'defense and military modernization' and build a 'world-class military force' by the nation's 100th anniversary in the 2050s. The US is busy checking China's rise by strengthening international cooperation and alliances. The security environment and power dynamics in Northeast Asia are slowly changing as the US and China continue to compete for global hegemony. The changes and implications of the distribution of power in Northeast Asia after 2030 are examined based on the balance of power theory.

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Service Learning: A New Approach in Science Education to Address Environmental Challenges (서비스 러닝: 환경문제를 다루기 위한 과학교육의 새로운 접근)

  • Byung-Yeol Park
    • Journal of Science Education
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    • v.46 no.3
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    • pp.278-292
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    • 2022
  • Researchers in science education have recently focused on service learning as an important educational approach to address environmental challenges including climate change. However, there are a limited number of studies focused on service learning in science education in Korea. In this study, based on existing related literature, the theoretical background of service learning is introduced and a conceptual framework that can be applied in the science education environment in Korea as a new approach to address environmental challenges is proposed. Given this, 112 relevant academic documents collected by searching a global database were analyzed. As a result, the theoretical background of service learning rooted in Dewey's experiential learning is introduced. Specifically, service learning is defined as a form of experiential learning that supports students in helping communities with structured services related to learning content, while at the same time fostering their in-depth understanding of content and engaging in civic and social responsibility as members of their community. In addition, a conceptual framework for service learning to address environmental challenges that can be applied to the science education environment in Korea is proposed. The proposed framework classifies the members of service learning into schools, students, and communities, and presents knowledge, experience, and learning through critical reflection as its core elements. It is important to actively implement service learning in science education to address various environmental challenges including climate change, biodiversity loss, air pollution, and deforestation, as just a few pressing challenges. Therefore, based on the proposed conceptual framework for service learning, studies that apply and verify diverse forms of educational approaches to addressing environmental challenges in local communities at school sites are needed.

A Study on the Architecture for Avionics System of Jet Fighters (제트 전투기의 항공전자 시스템 아키텍처에 관한 연구)

  • Gook, Kwon Byeong;Won, Son Il
    • Journal of Aerospace System Engineering
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    • v.16 no.1
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    • pp.86-96
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    • 2022
  • The development trend of jet fighter's avionics system architecture is the digitization of subsystem component functions, increased RF sensor sharing, fiber optic channel networks, and modularized integrated structures. The avionics system architecture of the fifth generation jet fighters (F-22, F-35) has evolved into an integrated modular avionics system based on computing function integration and RF integrated sensor systems. The integrated modular avionics system of jet fighters should provide improved combat power, fault tolerance, and ease of jet fighter control. To this aim, this paper presents the direction and requirements of the next-generation jet fighter's avionics system architecture through analysis of the fifth generation jet fighter's avionics system architecture. The core challenge of the integrated modularized avionic system architecture requirements for next-generation fighters is to build a platform that integrates major components and sensors into aircraft. In other words, the architecture of the next-generation fighters is standardization of systems, sensor integration of each subsystem through open interfaces, integration of functional elements, network integration, and integration of pilots and fighters to improve their ability to respond and control.

Changes of International Aviation Regimes (국제항공 레짐의 변화)

  • Lee, Jong-Sik
    • The Korean Journal of Air & Space Law and Policy
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    • v.17
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    • pp.55-89
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    • 2003
  • What are the international aviation regimes? It is said that they are sets of principles, norms, rules, and decision-making procedures of international aviation around which aviation actors' (states-actors, intergovernmental aviation organization, international aviation conventions, airlines and their organizations etc.) expectations converge in a given aviation issue-area for the purposes of the human welfare and the operations of the stable civil aviation. In this regards, the purposes of this study are focused on the aviation actors' shifts. Chronologically, international aviation regimes have been developed by some stages as followings; The 1st stage is the period from 1944 Chicago Convention to 1978 US Deregulation Act, when the aviation regulations and rules within the international aviation relations were implemented by Chicago-Bermuda regimes as Christer Jonsson pointed out. In this first stage, the sovereignty for the airspace over their countries is absolute. The second stage is the period from 1978 to '1992 Open Skies Agreement' between US and Netherlands. In this regime, airlines' activities as well as state-actors' have been actuated. The third stage is the period from 1992 to the contemporary. In this stage, airlines' activities for the consumers such as 'Open Skies Agreements', 'e-commerce business', 'airspace open policy within EU area', 'service open policy of WTO', and 'airlines' strategic alliance' are the central focal points in the world aviation relationship. In the conclusion, this phenomenon of the core actors in the international aviation rules has been shifted from the states-actors to the non-states actors especially, operating airlines, or consuming customers. Finally, I' d like to suggest that international aviation regimes should be developed to promote and facilitate the globalized level for the people's movements among the global aviation society. That is the way to proceed to the welfare and peace for all human beings of the World.

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A Study on the infringement of privacy of unmanned aircraft : Focusing on the analysis of legislation and US policy (무인항공기의 사생활 침해에 대한 법적 대응 : 미국 정책.입법안 분석을 중심으로)

  • Kim, Sun-Ihee
    • The Korean Journal of Air & Space Law and Policy
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    • v.29 no.2
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    • pp.135-161
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    • 2014
  • An unmanned aerial vehicle (UAV), commonly known as a drone and also referred to as an unpiloted aerial vehicle and a remotely piloted aircraft (RPA) by the International Civil Aviation Organization (ICAO), is an aircraft without a human pilot aboard. ICAO classify unmanned aircraft into two types under Circular 328 AN/190. Unmanned aircraft, which is the core of the development of the aviation industry. However, there are also elements of the legal dispute. Unmanned aircraft are manufactured in small size, it is possible to shoot a record peripheral routes stored in high-performance cameras and sensors without the consent of the citizens, there is a risk of invasion of privacy. In addition, the occurrence of the people of invasion of privacy is expected to use of civilian unmanned aircraft. If the exposure of private life that people did not want for unmanned aircraft has occurred, may occur liability to the operator of unmanned aircraft, this is a factor to be taken into account for the development of unmanned aircraft industry. In the United States, which is currently led by the unmanned aircraft industry, policy related to unmanned aircraft, invasion of privacy is under development, is preparing an efficient measures making. Unmanned aircraft special law has not been enforced. So there is a need for legal measures based on infringement of privacy by the unmanned aircraft. US was presented Privacy Protection Act of unmanned aircraft (draft). However Korea has many laws have been enacted, to enact a new law, but will be able to harm the legal stability, there is a need for the enactment of laws for public safety of life. Although in force Personal Information Protection Law, unmanned aerospace, when the invasion of privacy occurs, it is difficult to apply the Personal Information Protection Law. So, it was presented a privacy protection bill with infringement of privacy of unmanned aircraft in the reference US legislation and the Personal Information Protection Act.