• 대한기계학회논문집
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• 제12권1호
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• pp.152-162
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• 1988

본 연구에서는 열물성치 측정시 여러가지 어려운 수고를 가급적 줄이고 측정시간도 짧도록 하기 위해서 방평파 펄즈상가열법을 채용하여 이론적 검토와 고온에 유한원형인 시료로 부터 복사열손실을 최소화할 수 있는 방법을 고려하였다. 물론 시료는 전지회로의 용량소자, 콘텐서(condenser) 또는 전기절연이 주용도이며 유전율이 서로 다른 5종류의 세라믹 유전체에 관해서도 상온으로부터 약 1300k 까지 열물성치를 계측하였다. 특히 세라믹 유도체에는 유전율 및 기공율에 의한 열물성치가 가 다르기 때문에 그들사이의 관계에 대해서도 검토하였다.

• 정신신체의학
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• 제5권1호
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• pp.129-134
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• 1997

The meddle years start when persons achieve maturity and end when they realize they are old, and we commonly call ages between thirty-live and sixty five the middle years. Thinking of life as a play, the middle years lead up to and away from the climax of the plot. In the early part of middle age, the man is the main support of his family, and is out to establish himself in his career. He is in a race toward success, and may acquire a sponsor who picks him out as a protege. In the middle part of middle age, the man is ready to come into his own and may break with his sponsor. Most persons are now at the height of their potential, know their areas of competence, and have the satisfaction of feeling in control in them. They need no longer prove themselves from day to day, for they are credited with past accomplishments. Some are caught in "promotion or success depression", and some continue to change jobs creating difficulties is readjustment. The more satisfactory changes usually occur within a career rather than through shifiting careers. In e later part of the middle age the man worries about his physical health, and experiences depression in facing the retirement. Woman frequently change the course of their lives some time between the ages of thirty-five and forty, and may resume their education or careers. Tee quarters of women are passing through "involutional melancholia".

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 춘계학술발표회
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• pp.37-37
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• 2018

The genus Crepidiastrum (Asteraceae), containing ca. 20 species, is mainly distributed in Asia. Crepidiastrum denticulatum, an edible plant that commonly call "e-go-deulppae-gi" in Korean, distributes in Korea, Japan, and China. The complete chloroplast (cp) genome sequences of C. denticulatum was characterized from MiSeq2000 (Illumina Co.) pair-end sequencing data. The cp genome of C. denticulatum has a total sequence length of 152,689 bp and show a typical quadripartite structure. It consists of the large single copy (LSC: 84,022 bp), small single copy (SSC: 18,519 bp), separated by a pair of inverted repeats (IRs: 25,074 bp) and contains 110 unique genes and 18 genes duplicated in the IR regions. Our comparative analysis identified three cpDNA regions (matK, rbcL, and psbA-trnH) from three Crepidiastrum species, which may be useful for molecular identification of each species, and providing a guideline for its clear confirming about dried medical herb.

• 정보와 통신
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• 제28권9호
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• pp.3-9
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• 2011

본고에서는 급속히 성장하고 있는 M2M 서비스의 융합과 발전을 위해 어떤 걸림돌이 있으며, 무엇을 준비해야 하는지에 대해 알아보고자 한다. 지난 1T839 정책에서 3대 인프라의 하나로 정의된 USN이 본격 확산에 미흡했던 사항에는 어떤 것들이 있었으며 당시 기술적인 환경과 서비스 사례를 통해 2% 부족했던 것들은 되짚어 보고, USN이 현재 시점에 가지는 의미를 찾아보고자한다. USN 서비스가 활성화 되던 시점에 M2M의 기반기술이라고 할 수 있는 (W)CDMA 등 광역 무선망 기술과의 접목이 어려웠던 부분과 USN의 다양한 근거리 무선 네트워크 기술들이 USN 서비스를 완벽히 구현하고 확산까지 갈 수 없었던 미흡했던 이유를 알아보고자 한다. 또한 M2M의 시작배경에는 어떠한 의미가 있으며, 현재에서 바라본 M2M은 시작과 비교해서 달라진 점이 무엇이며 현재에 요구되는 M2M은 무엇인지에 대해 논의해보고자 한다. 이와 함께 M2M의 다양한 정의와 현재의 M2M을 비교해보고 M2M이 급속히 증가하고 있는 이유들을 찾아본다. M2M 서비스를 크게 나누면 텔레매틱스와 텔레매트리로 나눌 수 있으며 최근에는 차량 관련된 분야에 M2M 서비스가 급속히 증가되고 있는데 해외의 eCall 서비스와 국내의 DTG 연계 M2M 서비스, 국가위험물관리 등 국내외 차량관련 M2M 서비스 사례를 분석해 보고, RFID/USN+LBS+M2M의 융복합 서비스 진화에 대해 알아보고자 한다. 끝으로 M2M 시대의 시대적 요구사항을 반영하여 M2M의 활성화를 위해서 필요한 공공과 민간의 역할을 짚어보고, 우리가 준비해야할 것에 대해 제언하고자 한다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권5호
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• pp.2029-2043
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• 2018

In this paper, we propose a novel inter-cell handover approach from a new perspective in dense Heterogeneous and Small Cell Networks (HetSNets). We first devise a cell selection mechanism to choose a proper candidate small cell for the UEs that tend to implement inter-small cell handover (ICH). By exploiting the property of a typical non-concentric circle, i.e., circle of Apollonius, we then propose a novel analytical method for modeling inter-cell handover regions and present mathematical derivation to prove that the inter-small cell handover issues fit the property of the circle of Apollonius. We design an inter-cell handover algorithm (ICHA) by means of our proposed handover model to dynamically configure hysteresis margin and properly implement handover decision in terms of UE's mobility. Simulation results demonstrate that the proposed ICHA yields lower call drop rate and radio link failure rate than the conventional methods and hence achieve high Handover Performance Indicator (HPI).

• 한국컴퓨터정보학회논문지
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• 제24권3호
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• pp.77-86
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• 2019

The advent of Internet of Things (IoT) makes common nowadays computing environments involving programming not a single computer but several heterogeneous distributed computers together. Developing programs separately, one for each computer, increases programmer burden and testing all the programs become more complex. To address the challenge, this paper proposes an RPC-based unified programming language, UniPy, for development of MGC (eMbedded, Gateway, and Cloud) applications in IoT systems configured with popular computers such as Arduino, Raspberry Pi, and Web-based DB server. UniPy offers programmers a view of classes as locations and a very simple form of remote procedure call mechanism. Our UniPy compiler automatically splits a UniPy program into small pieces of the program at different locations supporting the necessary RPC mechanism. An advantage of UniPy programs is to permit programmers to write local codes the same as for a single computer requiring no extra knowledge due to having unified programming models, which is very different from the existing research works such as Fabryq and Ravel. Also, the structure of UniPy programs allows programmers to test them by directly executing them before splitting, which is a feature that has never been emphasized yet.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제10권1호
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• pp.29-34
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• 2021

실시간 화상교육은 원격지에서 강의자와 학습자의 면대면 교육을 대체하는 효과적인 수업 운영방식으로 활용되고 있다. 하지만 기존의 영상통화 및 화상회의 시스템을 활용하는 형태가 주를 이루고 있으며 이는 영상을 통한 강의에 치중하게 되어 어학교육에서 효과성을 보이고 있다. 그러나 그 외의 교육에서는 활용도가 미비한 실정이다. 최근 코로나로 인해 영상 중심의 화상 교육이 있으면서 화상 회의 시스템이 가지는 영상 중심 화상교육의 제한점을 개선하여 강의자와 학습 참여자 모두에게 수업 중 활용할 수 있는 기능을 제공한다. 본 논문에서는 수학교육에서 효과성을 향상시킬 수 있는 실시간 화상 시스템의 설계 모델을 제시한다.

• 대한안전경영과학회지
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• 제22권1호
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• pp.9-14
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• 2020

Artificial intelligence (AI) has been applied to most industries by enhancing automation and contributing greatly to efficient processes and high-quality production. This research analyzes the applications of AI-based automobile accident prevention systems. It deals with AI-based collision prevention systems that learn information from various sensors attached to cars and AI-based accident detection systems that automatically report accidents to the control center in the event of a collision. Based on the literature review, technological and institutional changes are taking place at the national levels, which recognize the effectiveness of the systems. In addition, start-ups at home and abroad as well as major car manufacturers are in the process of commercializing auto parts equipped with AI-based collision prevention technology.

• Asia pacific journal of information systems
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• 제29권3호
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• pp.503-523
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• 2019

Many cities in the world have increased initiative to realize smart tourism. There are unexplored challenges for the people which lead and manage smart tourism projects and realize its value in tourism (we call them as 'Smart tourism initiatives'), such as orchestrating of tourism complexity, developing and sharing tourism strategy, sustaining tourism projects and innovation. Concerning these challenges, we aim to design a holistic capability maturity model for sustainable and smart tourism governance enabling sustainable tourism innovations via tackling the challenges above. We adopted Dynamic capability theory as a theoretical lens and introduced Design science research methodology in order to develop a new capability maturity governance model as a design artifact. As a result of the study, we could synthesize findings from iterations of the design research cycle based on the IT Capability Maturity Model. Our result proposes a potential capability maturity model supporting effective communication and strategic alignment for the initiatives with illuminating future paths with evaluation methods on tourism capabilities for the initiatives. Throughout this study, we contribute to the body of knowledge as well as practice by proposing a new tourism capability governance model.

• 대한수학회보
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• 제25권2호
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• pp.203-209
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• 1988

In this paper, we define a g-regular semigroup which is a generalization of a regular semigroup. And we want to find some properties of g-regular semigroup. G-regular semigroups contains the variety of all regular semigroup and the variety of all periodic semigroup. If a is an element of a semigroup S, the smallest left ideal containing a is Sa.cup.{a}, which we may conveniently write as $S^{I}$a, and which we shall call the principal left ideal generated by a. An equivalence relation l on S is then defined by the rule alb if and only if a and b generate the same principal left ideal, i.e. if and only if $S^{I}$a= $S^{I}$b. Similarly, we can define the relation R. The equivalence relation D is R.L and the principal two sided ideal generated by an element a of S is $S^{1}$a $S^{1}$. We write aqb if $S^{1}$a $S^{1}$= $S^{1}$b $S^{1}$, i.e. if there exist x,y,u,v in $S^{1}$ for which xay=b, ubv=a. It is immediate that D.contnd.q. A semigroup S is called periodic if all its elements are of finite order. A finite semigroup is necessarily periodic semigroup. It is well known that in a periodic semigroup, D=q. An element a of a semigroup S is called regular if there exists x in S such that axa=a. The semigroup S is called regular if all its elements are regular. The following is the property of D-classes of regular semigroup.group.