• 제목/요약/키워드: Small world theory

검색결과 55건 처리시간 0.028초

초소형 풍력발전용 블레이드에 대한 구조설계 몇 해석 (Structural Design and Analysis for Small Wind Turbine Blade)

  • 이승표;강기원;장세명;이장호
    • 한국생산제조학회지
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    • 제19권2호
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    • pp.288-294
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    • 2010
  • In recent years, wind energy has been the world's fastest growing source of energy. This paper describes the structural design and analysis of composite blade for 2 kW-level HAWT (horizontal axis wind turbine). The aerodynamic design and force, which are required to design and analyze a composite blade structurally, are calculated through BEMT(blade element momentum theory) implemented in public code PROPID. To obtain the equivalent material properties of filament wound composite blades, the rule-of-mixture is applied using the basic material properties of fiber and matrix, respectively. Lay-up sequence, ply thickness and ply angle are designed to satisfy the loading conditions. Structural analysis by using commercial software ABAQUS is performed to compute the displacement and strength ratio of filament wound composite blades.

Topological and Statistical Analysis for the High-Voltage Transmission Networks in the Korean Power Grid

  • Kang, Seok-Gu;Yoon, Sung-Guk
    • 한국통신학회논문지
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    • 제42권4호
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    • pp.923-931
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    • 2017
  • A power grid is one of the most complex networks and is critical infrastructure for society. To understand the characteristics of a power grid, complex network analysis has been used from the early 2000s mainly for US and European power grids. However, since the power grids of different countries might have different structures, the Korean power grid needs to be examined through complex network analysis. This paper performs the analysis for the Korean power grid, especially for high-voltage transmission networks. In addition, statistical and small-world characteristics for the Korean power grid are analyzed. Generally, the Korean power grid has similar characteristics to other power grids, but some characteristics differ because the Korean power grid is concentrated in the capital area.

Particle Swarm Optimization based Haptic Localization of Plates with Electrostatic Vibration Actuators

  • Gwanghyun Jo;Tae-Heon Yang;Seong-Yoon Shin
    • Journal of information and communication convergence engineering
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    • 제22권2호
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    • pp.127-132
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    • 2024
  • Haptic actuators for large display panels play an important role in bridging the gap between the digital and physical world by generating interactive feedback for users. However, the generation of meaningful haptic feedback is challenging for large display panels. There are dead zones with low haptic sensations when a small number of actuators are applied. In contrast, it is important to control the traveling wave generated by the actuators in the presence of multiple actuators. In this study, we propose a particle swarm optimization (PSO)-based algorithm for the haptic localization of plates with electrostatic vibration actuators. We modeled the transverse displacement of a plate under the effect of actuators by employing the Kirchhoff-Love plate theory. In addition, starting with twenty randomly generated particles containing the actuator parameters, we searched for the optimal actuator parameters using a stochastic process to yield localization. The capability of the proposed PSO algorithm is reported and the transverse displacement has a high magnitude only in the targeted region.

의과대학생 국가시험 거부 사태에 대한 고찰: 신호게임 이론을 중심으로 (A Study on the Refusal of National Examination for Medical Students: Focusing on the Signaling Game Theory)

  • 현승효;김다영;이민규
    • 보건행정학회지
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    • 제31권4호
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    • pp.479-490
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    • 2021
  • Background: Conflict in the medical world in 2020 led to the rejection of the national examination for doctors. This study explained the process until the end of the national test refusal situation triggered in 2020 through the signaling game theory. The government has succeeded in requiring medical students to take the national exam. Methods: To explain the rejection of the national examination, we first compose and show an example of two small non-signaling games where medical students know which type the government is of, then combine them to play a signaling game. Results: The behavior of the government and medical students was examined through the signaling game model. In the context of the coronavirus disease 2019 (COVID-19) pandemic, the government makes an ultimatum, whatever the type. And the medical students accept it. They judged that the government could not be expected to abolish the policy. If COVID-19 had not occurred, medical students would have been able to continue the confrontation. Conclusion: The government instilled in the other party the perception that the government would not bend its policies because it was the surly type and would not be afraid of a strong confrontation. Through the image created in this way, the government was forced to accept the ultimatum by medical students. Academically, this study is to deal with the policy-making process through the signaling game theory. In the area of health care policy, this study suggests that various situations such as the type of government or the spread of COVID-19 can become important in addition to the rationality of the policy itself.

금융(金融)의 전업(專業) 및 겸업화(兼業化) 이론(理論): 금융산업조직론(金融産業組織論)의 모색(摸索) (A Theory on the Scope of Financial Activity)

  • 좌승희
    • KDI Journal of Economic Policy
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    • 제13권1호
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    • pp.167-197
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    • 1991
  • 최근의 세계금융산업(世界金融産業)은 이종금융업무간(異種金融業務間)의 통합(統合)(겸업(兼業))과 동시에 이와는 반대로 개별업무(個別業務)의 분할현상(分割現象)을 동시에 같이 경험하고 있는데, 본고(本稿)는 이러한 금융산업조직(金融産業組織)의 내생적(內生的) 재편현상(再編現象)을 체계적으로 설명할 수 있는 금융산업조직이론(金融産業組織理論)을 모색하는 데 그 목적이 있다. 기존의 전문화(專門化)와 겸업화이론(兼業化理論)을 통합한 잠정적 분석체계는 대체로 다음과 같은 시사점을 주고 있다. 첫째로, 독자적으로는 규모(規模)의 경제(經濟)가 강하고 여타 업무와는 범위(範圍)의 비경제하(非經濟下)에 있거나 범위(範圍)의 경제(經濟)가 약한 업무는 기존 업무세트에서 분할(分割) 전문화(專門化)될 것이다. 둘째로, 여타업무와는 범위(範圍)의 경제(經濟)가 강하면서, 독자적으로는 규모(規模)의 비경제하(非經濟下)에 있거나 혹은 규모(規模)의 경제(經濟)가 약한 업무는 겸업(兼業)될 것이다. 셋째로, 자유금융하(自由金融下)의 경쟁금융산업균형(競爭金融産業均衡)은 겸업기업(兼業企業)과 전업기업(專業企業)이 공존하는 혼합균형(混合均衡)이 될 것이다. 넷째로, 금융산업조직(金融産業組織)의 국가별 차이는 금융시장(金融市場) 및 수요규모(需要規模)의 차이에 의해 결정되며, 최근 진행되고 있는 금융(金融)의 세계화(世界化) 국제화(國際化)는 각국이 직면하게 될 금융시장(金融市場)의 규모를 균등화시킴으로써 장기적으로 각국 금융산업조직(金融産業組織)의 동질화(同質化)를 촉진시킬 것이다. 다섯째로, 금융제도(金融制度)에 대한 인위적 규제가 없다면 겸업주의(兼業主義) 은행제도(銀行制度)는 금융시장(金融市場)의 규모(規模)가 상대적으로 작은 경제에서, 전업주의(專業主義) 은행제도(銀行制度)는 금융시장의 규모가 상대적으로 큰 경제에서 주로 관찰되게 될 것이다. 본고(本稿)는 이러한 시사점들을 응용하여 주요국에 있어서의 전업주의(專業主義)와 겸업주의(兼業主義) 은행제도(銀行制度)의 역사적 변천과정을 각국 금융시장규모(金融市場規模)의 변천과정에 의해 설명하고, 현재 구조변화(構造變化)를 경험하고 있는 세계각국(世界各國) 금융산업조직(金融産業組織)은 장기적으로 구조가 동질화(同質化)되면서 혼합균형상태(混合均衡狀態)로 이행해 나갈 것으로 전망하고 있다.

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Small Business Innovation Research Program in the United States: A Political Review and Implications for East Asian Countries

  • Ryu, Youngbok
    • STI Policy Review
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    • 제6권2호
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    • pp.54-86
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    • 2015
  • The study examines the U.S. Small Business Innovation Research (SBIR) program, with a focus on the recent Reauthorization, and compares, in the political context, the U.S. and East Asian countries-Japan, Korea and Taiwan-that adopted the U.S. SBIR program. For the systematic analysis and cross-country comparison, the study employs Kingdon (2003)'s framework-his political theory and Garbage Can Model-to identify political participants and processes underlying the SBIR Reauthorization and to analyze the differences in problem, policy, and politics streams between the U.S. and East Asian countries. For the cross-country comparison, specifically, the study uses various data sources such as OECD, Global Entrepreneurship Monitor, Hofstede's Cultural Dimensions, and World Value Survey. Based on the analysis outcomes, implications of U.S. practices on East Asian countries are extracted as follows. East Asian countries tend to: Have higher entrepreneurial aspiration while lower entrepreneurial activity and attitude than the U.S.; bear higher long term orientation and uncertainty avoidance while lower individualism than the U.S.; and have greater expectations of technology development and higher confidence in political parties while participating less in political action than the U.S. Drawing on the differences, the following policy recommendations are suggested. East Asian countries should: Improve entrepreneurs' access to resources (in particular, financial resource) in order to link their high entrepreneurial aspiration to actual entrepreneurial activities; cultivate failure-tolerating culture and risk-taking entrepreneurs, for instance, by providing a second chance to SBIR-participating businesses that failed to materialize their innovative ideas; and leverage their high expectations of new technology in order to take bold actions regarding their SBIR programs, and update the programs by drawing out constructive dialogues between SBIR stakeholders.

유럽 상징주의 복식에 관한 연구 -구스타브 클림트(Gustav Klimt)의 회화 세계를 중심으로- (A Study on the European Symbolist Costume -Focusing on Gustav klimt's Art World-)

  • 양숙희
    • 복식
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    • 제22권
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    • pp.277-296
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    • 1994
  • The progressive artists in Austria including Gustav Klimt organized the Viennes Se-cessionist in 1897 and they took an active part in the reformation of the reformation of the applied art by accepting the Jugendstil standing for the true art. The vocabularies which characterize this group are decoration literature and the power of symbol. Klimt especially expressed these characteristics and his strong person-ality. For he created his works with the sym-bolic and friendly splendor through his highly decorative talents by accepting the enwly changed artistic situation in those days and by getting out of the naturalistic trends he was regarded as an avant-garde artist as a major figure among the Symbolist artists who revived European culture which was destroyed through the World War I. The characteristics of klimt's works was to express the various human thoughts and minds through the decorativeness and the femininity and to use the decorative elements of old Greek and Egyptian culture and Japanese art as the motives of his works, His art is to be found between the naturalistic characteristics and formalization as well as between the in-dustrial arts and the fine arts. In his many portraits he preferred women by trying to express eroticism hidden behind the human inner world. For this he demonstrated the attractiveness and the characteristics of the models by designing the illusionary and unique clothes. In general his genius was to be seen through the costume which was decorated with metals and jewels and through the characteristics of the modern costume in which the previous solid silhouette was removed and the gentle and elegant me-dium color was used. by accepting the new artistic trends in the turn of the century by fully expressing those characteristics in his creative world and by taking his theme from the eroticism through the decorativeness and the expression of women Gustav Klimt's uniquely decorative ex-pression completely realized the aesthetics of Jugendstil symbol decoration and expression which displayed not only the external appear-ance but also the inner world. Especially he created a new appearance emphasizing the costume of the characters in his works. Also through the costume he expressed his artistic consciousness and psy-chology. He showed the characteristics of the reformed costume through the medium color the simple forms and gentle silhouette. Also he tried to symbolize the passionate inner pow-er by designing the small mosaics such as the geometrical patterns whirlpool patterns and the indecent meanings all over the costume. Klmt's this kinds of attemps shows a Stil Kostume as the external outcome of the inner spiritual activities like art and it establishes a basis for the theory of costume are which deals with the concepts of costume from the artistics points of view. This tradition playing an important role in the contemporary history of costume even has been still inherited up to today.

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조선시대 무속복식연구-좌당 내력을 중심으로- (A Study on the Apparels of Shamanism during Cho Sun Dynasty)

  • 조효순
    • 복식
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    • 제34권
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    • pp.195-208
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    • 1997
  • 1) The color of JOGORI and CHIMA was such gorgeous and those garments were put on during the events of GAM-EUNG-CHUNG-BAI HO-GU-GEO-RI JO-SANG-GEO-RI DEWT-JUN and CHAN-BOO-GEO-RI. 2)BULSA-JANG-SAM(JE-SUK-GEO-RI) was white colored and had wide sleeves putting on a pink priestrobe and a pink belt on it 3) they put on HONG-CHUL-NIK(GU-REUNG) and CHONG-CHUL-NIK(DAE-GEO-RI). 4)They put on GOO-GUN-BOK(JUN-RIP JUN-BOK(BYUL-SUNG-GEO-RI) DONG-DA-RI(Expel the demon) 5) MONG-DOO-RI(MAN-SIN-MAL-BYUNG) put on the garment constructed with the color and from of a white straight collar a wide sleeve and a pink belt 6) A long robe was colored with green (GAM-EUNG-CHUNG-BAI) and was used not as a headdress but as a man's overcoat. 7) CHANG-EUI was a green colored small CHAHG-EUI(SUNG-JO-GEO-RI). As observed above the Shaman apprel during Chosun Dynasty is a part of the traditional clothing originated from THE THEORY OF THE COSMIC DUAL FORCES and THEORY OF THE COSMIC DUAL FORCES and the FIVE ELEMENTS (i.e. metal wood water fire and earth) It's basic form and wearing method were not so different from the traditional clothing silmilar to the official uniform during Chosun Dynasty and the official uniform was the symbol of authority(almost almighty) at that time of period and to that the Shaman apparel was constructed with the more gorgeous colors to emphasize the sanctity or the descent of the Divine Being from heaven. We realized that a Shaman had put on the symbolic garment suitable for the grade and nature of the Divine Body at every events to enter into " The World of Gods"Gods."

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Predicting Discharge Rate of After-care patient using Hierarchy Analysis

  • Jung, Yong Gyu;Kim, Hee-Wan;Kang, Min Soo
    • International Journal of Advanced Culture Technology
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    • 제4권2호
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    • pp.38-42
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    • 2016
  • In the growing data saturated world, the question of "whether data can be used" has shifted to "can it be utilized effectively?" More data is being generated and utilized than ever before. As the collection of data increases, data mining techniques also must become more and more accurate. Thus, to ensure this data is effectively utilized, the analysis of the data must be efficient. Interpretation of results from the analysis of the data set presented, have their own on the basis it is possible to obtain the desired data. In the data mining method a decision tree, clustering, there is such a relationship has not yet been fully developed algorithm actually still impact of various factors. In this experiment, the classification method of data mining techniques is used with easy decision tree. Also, it is used special technology of one R and J48 classification technique in the decision tree. After selecting a rule that a small error in the "one rule" in one R classification, to create one of the rules of the prediction data, it is simple and accurate classification algorithm. To create a rule for the prediction, we make up a frequency table of each prediction of the goal. This is then displayed by creating rules with one R, state-of-the-art, classification algorithm while creating a simple rule to be interpreted by the researcher. While the following can be correctly classified the pattern specified in the classification J48, using the concept of a simple decision tree information theory for configuring information theory. To compare the one R algorithm, it can be analyzed error rate and accuracy. One R and J48 are generally frequently used two classifications${\ldots}$

트위터를 통한 제조 기업의 부정적 구전 확산: 공급사슬 리스크 관점에서 (Spread of Negative Word-of-mouth of Manufacturing Companies Via Twitter: From the Supply Chain Risk's Perspective)

  • 정의범;유한나
    • 한국산업정보학회논문지
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    • 제26권5호
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    • pp.79-94
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    • 2021
  • 소셜 미디어상의 부정적 구전에 대한 기업의 공급사슬 리스크의 중요성과 심각성에도 불구하고 관련된 연구는 미흡한 실정이다. 이에 본 연구는 제품의 부정적 구전이 소셜 미디어를 통해 어떻게 유통되는지, 부정적 구전의 유통과 확산에 영향을 주는 주체의 특징은 무엇인지를 사회적 교환이론에 기초하여 분석하였다. 이를 위해 트위터를 이용해 미국도로교통안전국(NHTSA)에서 4개 자동차 기업의 자동차 리콜 정보를 수집하였다. 최초 트위터(Seed tweet)를 바탕으로 부정적 구전의 유통과 확산을 살펴보기 위한 RT(Re-tweet) 네트워크를 구조를 분석하여 부정적 구전 네트워크의 특징을 파악하고, 초기 유포자의 특성이 부정적 구전 확산에 미치는 영향을 분석하였다. 그 결과 부정적 구전은 다수 이용자와 연결된 허브 이용자를 중심으로 확산하는 스몰월드 네트워크 구조임을 확인하였으며, 초기 유포자의 영향력이 크고 상호호혜성이 높을수록 부정적 구전 확산의 속도와 규모가 유의미하게 증가함을 발견하였다.