• 제목/요약/키워드: Mass communication

검색결과 980건 처리시간 0.026초

비정상 위치 및 이중혈액공급을 받는 외엽형 폐격리증 -1례 보고- (Extralobar Pulmonary Sequestration of Unusual Location and Dual Blood Supply -A Case of Report-)

  • 서성구
    • Journal of Chest Surgery
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    • 제27권9호
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    • pp.804-807
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    • 1994
  • Pulmonary sequestration is an unusual congenital malformation characterized by the presence of nonfunctioning lung tissue which usually has no communication with the normal bronchial tree and receives its blood supply from an anomalous systemic artery. Extralobar form is a very rare congenital malformation. We have experienced a 54 year old female patient with a mass in the upper lobe complaining of cough and blood tinged sputum. A triangular shaped mass was located in the left upper lobe, medially. The arterial blood supply were from the thoracic aorta and the pulmonary artery but there was no the tracheobronchial communication. The venous drainage was through the pulmonary vein. The mass was confirmed as extralobar pulmonary sequestration associated with a pericardial defect.

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정지궤도 통신위성의 추진시스템 개념설계 연구

  • 박응식;박봉규;김정수
    • 항공우주기술
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    • 제1권1호
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    • pp.55-64
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    • 2002
  • 수명 12년의 중형급 정지궤도 통신위성의 추진시스템 개념설계과정이 기술된다. 임무해석을 통해 주어진 전속도 증분량(ΔV)을 사용하여 임무수명기간동안 필요한 추진제 양이 계산되었으며 이 값을 기초로 하여 연료탱크와 산화제 탱크의 형상을 설계하였고 필요한 가압제의 양과 가압제 탱크의 압력을 구할 수 있었다. 구조계와 Trade-Off Study를 통해 추력기의 배치와 로켓엔진의 개수, 탱크의 배치 등을 결정하였으며 전체적인 추진시스템 개념설계 형상이 최종적으로 제시된다.

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IT제조기업의 베트남 진출 전략 및 성과에 관한 연구 (IT Manufacturing Companies' Strategies and Performance for Overseas Expansion to Vietnam)

  • 윤혜정;장창환;이중정
    • 한국IT서비스학회지
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    • 제16권3호
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    • pp.1-15
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    • 2017
  • This study is aimed to find out which factors among firm-specific resources, industry-based competition, and institutional conditions affect strategies for Korean IT manufacturing companies when they expand their business overseas, especially to Vietnam in this study. Also, it attempts to reveal which strategies among cost reduction, mass production, and localization affect performance of overseas expansion. Based on Strategy Tripod Theory as an integrating point-of-view embracing resource-based view, industry-based view, and institution-based view, research model was developed and tested through the survey of 83 Korean IT manufacturing companies expanded their business to Vietnam. Research findings show that (1) communication competency, industry competitiveness, industry attractiveness, and regulation of partner country affect cost reduction strategy. (2) International experience, communication competency, international orientation, and competitiveness is significantly associated with mass production strategy. (3) And international experience, communication competency, and industry competitiveness affect localization. (4) Ultimately, mass production strategy and localization strategy significantly increase performance of expansion to Vietnam. The theoretical contribution of this study is to adopt an integrative approach based on strategy tripod theory. As practical implications, it suggests factors and strategies that IT manufacturing companies interested in expansion to Vietnam should consider. In sum, we believe this study can contribute to Korean IT manufacturing industry by suggesting key success factors and appropriate strategies for overseas expansion.

자율운항선박 도입에 따른 선박교통관제 업무 변화에 관한 연구 (Study on Changes in Vessel Traffic Services Due to Introduction of Maritime Autonomous Surface Ships)

  • 김대원;이명기;박상원;박영수
    • 한국항해항만학회지
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    • 제47권6호
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    • pp.430-436
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    • 2023
  • 자율운항선박 관련 기술개발은 2010년도 중반부터 충돌회피, 항로 지정, 디지털 트윈 및 통신 기술개발 등의 주제로 활발하게 진행되고 있다. 그러나, 이와 비교하여 자율운항선박과 연계된 물류시스템, 항만시설 및 선박교통관제 등의 육상 인프라에 관한 연구는 상대적으로 관심을 받지 못하고 있다. 이 연구에서는 자율운항선박의 등장에 따라 기존 선박교통관제 업무에 미치게 되는 영향을 분석함과 동시에 이를 대비하기 위한 관제 업무 변화 방안을 제시하였다. 이를 위하여 현행 선박교통관제 업무를 분석하고, 동시에 자율운항선박 기술 중 선박교통관제에 영향을 미칠 수 있는 요소를 파악하였다. 또한, 선박교통관제사들을 대상으로 자율운항선박 관제 관련 항목 도출을 위한 설문조사를 수행하였으며, 이를 AHP 기법으로 분석한 결과 비상 상황 대응 및 자율운항선박과의 통신 방법에 대한 준비가 가장 중요한 것으로 도출되었다. 이를 기반으로 해상교통관제구역 내에서 데이터 통신을 기반으로 한 기본적인 자율운항선박 관제 절차 및 비상 대응 절차 등 세부 방안을 도출할 수 있었다. 이 연구에서 제안하는 자율운항선박 관제 절차는 향후 자율운항선박의 연안 해상교통안전에 관한 문제점들을 해소하는 방안으로 활용될 수 있을 것으로 기대된다.

A Case of Cavitated Uterine Mass from Müllerian duct in a Mixed Breed Dog

  • Park, Chul-Ho;Son, Chang-Ho
    • 한국임상수의학회지
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    • 제35권6호
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    • pp.279-281
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    • 2018
  • This report describes a case of newly recognized congenital $M{\ddot{u}}llerian$ duct anomaly in a bitch. A fourteen-year-old, mixed breed bitch was presented with mild hematuria and mammary gland tumor. Complementary examinations were performed and abdominal ultrasonography revealed distended uterine horns and uterine tumor-like mass around the right ovarian area. Macroscopic examination showed the mass to be on the level of insertion of the right round ligament. The mass was cystic in nature, and had no communication with the uterine cavity. Histopathologically, the mass was identified as an accessory cavity lined by functional endometrium, which confirmed the diagnosis of accessory and cavitated uterine mass.

터빈 발전기 축 시스템의 다중 질량체 모델링을 통한 비틀림 응답 구현 (Realization of Torsional Response based on Multi-mass Modeling of Turbine-Generator Shaft System)

  • 박지경;조규정;손승현;정세진;김철환
    • 전기학회논문지
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    • 제64권2호
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    • pp.201-207
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    • 2015
  • Turbine-generator torsional response is caused by interaction between electrical transient air-gap torque and mechanical characteristics of turbine-generator shafts. If torsional shaft torque exceeds a certain threshold, the loss of fatigue life may occur and, in the end, it is possible to happen permanent shaft failure. Therefore, it is required to understand the torsional response for reliable operation and protection of turbine-generator shaft system. In this paper, we introduced multi-mass modeling method of turbine-generator shaft system using mechanical-electrical analogy and state-space equation to verify the transient torsional response based on ElectroMagnetic Transient Program (EMTP). These simple realization methods for turbine-generator shaft torsional response could be helpful to understand torsional interaction phenomena and develop the transient torque reduction countermeasures for turbine-generator shaft system.

Factors Influencing Resistance to the Metaverse: Focusing on Propagation Mechanisms

  • Mina Lee;Minjung Kim
    • International journal of advanced smart convergence
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    • 제13권2호
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    • pp.110-118
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    • 2024
  • This study examines factors influencing nonusers' resistance to the adoption of the metaverse, focusing on propagation mechanisms. It elucidates the role of innovation resistance within the metaverse adoption process. We applied the Innovation Resistance Model in the context of the metaverse and considers three major groups of factors influencing resistance to the metaverse: innovation characteristics (perceived usefulness, compatibility, perceived risk, and complexity), consumer characteristics (personal innovativeness), and propagation mechanisms (mass media, online media, and personal communication). An online survey of college students who do not use the metaverse revealed that perceived usefulness, compatibility, personal innovativeness, and online media were negative predictors of resistance to the metaverse. Conversely, perceived risk, mass media, and personal communication were positive predictors of resistance to the metaverse. Furthermore, innovation resistance was found to play a mediating role in the metaverse adoption process. Drawing upon the findings, we suggested marketing strategies to decrease resistance to the metaverse.