• 제목/요약/키워드: Dynamic Coordination

검색결과 176건 처리시간 0.036초

동적 경쟁윈도우를 이용한 Ad Hoc 망에서의 Medium Access Control 프로토콜 (Medium Access Control Protocol for Ad Hoc Networks Using Dynamic Contention Window)

  • 안홍영
    • 한국인터넷방송통신학회논문지
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    • 제8권4호
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    • pp.35-42
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    • 2008
  • DCF 성능 분석 모델에 사용되는 Bianchi의 2차원 Markov Chain 모델은 오류가 없는 이상적 채널에서 충돌 문제만을 다루므로 페이딩, 간섭, 잡음 등 실제 채널의 특성을 반영하지 못한다. 802.11 DCF는 전송실패가 충돌에 의한 것이든, 채널 전송오류에 의한 것이든 경쟁윈도우(CW) 크기를 두 배로 증가시키는 2진 지수후퇴 알고리즘을 작동시킨다. 이상적으로 경쟁윈도우 증가는 혼잡에 의한 충돌방지 때에만 사용되어져야 한다. 통신오류에 의한 경쟁윈도우 증가는 데이터 처리율을 떨어뜨리고 전송지연의 증가를 야기 시킨다. 오류 채널에서는 전송실패 증가가 과도한 이진 지수후퇴를 야기하므로 초기 경쟁윈도우(CW) 크기를 줄여줄 필요가 있다. 본 논문에서는 경쟁윈도우(CW), 타임슬롯에서 전송 확률(${\Im}$), 전송 실패 확률($p_f$) 등이 시스템 성능에 미치는 영향을 정량적, 정성적으로 분석을 하고 등가적으로 CW 값을 얼마큼 줄여야 할지를 제시한다.

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저항운동치료 처방에 관한 연구 (A Study of Resistive Therapeutic Exercise Prescription)

  • 배성수;김태숙;김은주
    • The Journal of Korean Physical Therapy
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    • 제11권1호
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    • pp.149-156
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    • 1999
  • Resistive therapeutic exercise prescription goal is to improve functional performance and capabilities through the development of increased muscular strengh endurance or power. Resistance can be applied to either dynamic or static muscle contractions. Resistive therapeutic exorcise can be carried nut concentrically, eccentrically, isometrically, isokinetically. Neurodevelopmental treatment has not resistive therapeutic exercise concept. But proprioceptive neuromuscular facilitate techniques have resistive therapeutic exercise concept with pattens and techniques. It is aid muscle contraction, motor control and increase strength. Manual muscle testing will help the therapist establish a qualitative and quantitative baseline level of strength. Manual resistance maybe applied a against controlled lengthening contraction re static contraction of a muscle. A repetition maximum is not easy to calculate and is not the most accurate method available today to measure strength before of after a resistive therapeutic exercise program. Oddvar Holten Diagram is essy to calculate and is the most accurate method available today to measure strength before of after a resistive therapeutic exercise program. Plyometric training emphasize the development of muscular power and coordination. Quick bursts of force in functional movement patterns are often necessary of a patient is to return to high-demand occupational, recreational or sports related activities.

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전원사고 시 3상 계통연계 인버터의 전원 전압 고속 검출 방법 (High Speed Grid Voltage Detection Method for 3 Phase Grid-Connected Inverter during Grid Faults)

  • 최형진;송승호;정승기;최주엽;최익
    • 한국태양에너지학회 논문집
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    • 제29권5호
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    • pp.65-72
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    • 2009
  • The new method is proposed to improve high speed detection of grid voltage phase and magnitude during a voltage dip due to a grid faults. Usually, A LPF(Low Pass Filter) is used in the feedback loop of PLL (Phase Locked Loop) system because the measured grid voltage contains harmonic distortions and sensor noises. so, a new design method of the loop gain of the PI -type controller in the PLL system is proposed with the consideration of the dynamics of the LPF. As a result, a better transient response can be obtained with the proposed design method. The LPF frequency and PI controller gain are designed in coordination according to the steady state and dynamic performance requirement. This paper shows the feasibility and the usefulness of the proposed methods through the computer simulation and the lab-scale experiments.

3D 디지털 기술을 활용한 패션 갤러리 제작에 관한 연구 (A Study on the Application of 3D Digital Technology to Producing Cyber Fashion Gallery)

  • 김지언
    • 복식문화연구
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    • 제15권3호
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    • pp.446-460
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    • 2007
  • This study shows that digital technology is adapted practical method in fashion design process and virtual simulation and cyber fashion gallery based on virtual reality are researched. This study is proposed the 3D fashion design simulation in the virtual space used on 3D studio max, poser, photoshop program according to fashion design process. The main design concept is "temporary bridge" from rainbow. This study is supposed six fashion design in accordance with three sub-theme under main concept by changing color and texture used on 3D simulation. The results of this study are as follows: 1. This study produced Cyber Fashion Gallery in virtual space to the form of CD Rom title and web title by Macromedia Director 8.5, Macromedia Flash, Sound Forge. And it is enlarged the field of expression in aspect of Fashion Exhibition, beyond restriction of time and space. 2. Clothes modelling tools is able to easily adapt to various textiles and patterns in 3D dynamic virtual mannequin before making clothes. Digital technology is able to express image changed color and texture, especially new material, multi-finishing material and brilliant material and so on. So this study is able to develop tools for study of fashion coordination. 3. Cyber Fashion Gallery consists of gallery, story, painting, symbolism, example, image, quit. This study is enlarged the range of clothing expression by digital technology and open to possibility customized-manufacture.

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구매후기 정보의 충족/미충족에 따른 소비자의 만족/불만족 인식 및 구매후기 정보의 유형화 (Classification of Consumer Review Information Based on Satisfaction/Dissatisfaction with Availability/Non-availability of Information)

  • 홍희숙
    • 한국의류학회지
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    • 제35권9호
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    • pp.1099-1111
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    • 2011
  • This study identified the types of consumer review information about apparel products based on consumer satisfaction/dissatisfaction with the availability/non-availability of consumer review information for online stores. Data were collected from 318 females aged 20s' to 30s', who had significant experience in reading consumer reviews posted on online stores. Consumer satisfaction/dissatisfaction with availability or non-availability of review information on online stores is different for information in regards to apparel product attributes, product benefits, and store attributes. According to the concept of quality elements suggested by the Kano model, two types of consumer review information were determined: Must-have information (product attribute information about size, fabric, color and design of the apparel product; benefit information about washing & care and comport of the apparel product; store attribute information about responsiveness, disclosure, delivery and after service of the store) and attracting information (attribute information about price comparison; benefit information about coordination with other items, fashionability, price discounts, value for price, reaction from others, emotion experienced during transaction, symbolic features for status, health functionality, and eco-friendly feature; store attribute information about return/refund, damage compensation and reputation/credibility of online store and interactive and dynamic nature of reviews among customers). There were significant differences between the high and low involvement groups in their perceptions of consumer review information.

중도 정신지체아동의 보행 후 이동동작 개선에 관한 연구 - 단일 사례 연구 - (A Study on Improvement of Postwalk Locomotion in Child with Severe Mental Retardation : Single Subject)

  • 송주영;이효정;김진상;최진호
    • The Journal of Korean Physical Therapy
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    • 제12권1호
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    • pp.119-127
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    • 2000
  • In this case report we demonstrated the improvemen of gait pattern and the facilitation of postwalk locomotion on the child who has severe mental retardation with Incomplete gait pattern. Treatments included to stimulate vestibular using balance board and vestibular stimulator, to train weight hearing and shifting, to facilitate visual perception motor coordination, and to train walk ann postwalk locomotion in environment similar to actual daily life. It was performed 130 sessions for 10 months. With this treatment, she could accomplished dynamic stability so that she didn't fall at walk after $1\~2$ months of treatment, and could have done climbing up and down without hand support after 10 months. In gross motor function measure(GMFM), total motor function was improved to $89.98\%$ from $73.53\%$.

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통합건강관리간호사 역할규명을 위한 직무분석: 연 회원제 건강관리 서비스 중심 (Job Analysis of Health Guide Nurse for Role Identification: Focusing on Annual Health Guidance Membership Service)

  • 심원희;이주연
    • 간호행정학회지
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    • 제22권2호
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    • pp.129-136
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    • 2016
  • Purpose: The aim of this study was to identify nurses' role in the delivery of health guidance service within the annual health guidance membership service. Methods: Dynamic job analysis process was applied with vertical job analysis and horizontal job analysis through a focus group workshop and expert survey. Results: As a result of this study, job description was established with 4 duties, 11 tasks, 60 task elements. Major duties consisted of 'professional nurse practice', 'coordination and cooperation', 'education and consultation', and 'administrative work and improvement'. A job process map was also framed. Conclusion: The results can be used to establish nurses' role in providing health care service. Ongoing research on nurse's role as a health guider will be a fundamental base for health care service development and will contribute to expansion of common health management services.

대학생 봉사학습에 관한 실증적 사례연구 (An Experiential Study on Service Learning Experiences of University Students)

  • 김통원;김혜란
    • 한국사회복지학
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    • 제47권
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    • pp.148-177
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    • 2001
  • Service learning usually has two aspects. One aspect is associated with applying class learning to related fields. The other aspect is associated with challenging and dynamic volunteering experiences. This study examined experiences of 70 social work students who took service learning courses at a university. After the courses, these students were asked regarding (1) evaluation and satisfaction of overall service learning experiences, (2) evaluation of service learning contents and the following activities, (3) the process of volunteering activities, and (4) the differences between service learning courses and other regular courses. Results were as follows: students generally regarded service learning experiences as positive; students reported understanding of social work practice and learning of professional skills; however, the service learning courses seemed to be very demanding in time and adjusting personal schedules; teamwork among students seemed to be good, especially in cooperation and emotional support; however, some students reported struggling experiences in allocating roles among team members; finally, the relationship between students and social workers at the agencies and the coordination of community resources seemed to be weak. In order for service learning courses to be more effective, this study presented some suggestions in the conclusion.

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A Conceptual Framework for Value Co-creation in an Innovation Ecosystem: The Case of Technology-based Collaboration Network

  • 한은정;홍순구
    • 한국산업정보학회논문지
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    • 제22권4호
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    • pp.29-43
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    • 2017
  • Innovation Cosystems are Conceptualized as Organizational Networks of Economic Actors, Technologies and Social Contexts that Interact for Knowledge Production, use, and Adaptation. This Paper Proposed a Conceptual Framework to Describe Value Co-creation of Organizational Networks Engaged in Technology Innovation. We Adopted Theory-Based Approach by Integrating the Perspective of Service-Dominant (S-D) Logic Into the Evolutionary Model of the Triple Helix. The Framework Gives a Plausible Explanation on how Actors Collaborate to Create Value in Dynamic Contexts of an Innovation Ecosystem. The Innovation Ecosystem can be Considered as a Composite of Sub-Ecosystems, Including Knowledge, Sectoral, and Business Ecosystems. When these Sub-Ecosystems are Recursively Transformed by Coordination of Functional Mechanisms that Serve Value Co-creation in the Innovation Process, the Innovation Ecosystem will be Re-Organized and Evolve. The case of the Digital Living Network Alliance (DLNA) was Examined to Demonstrate the Fundamental Mechanisms for Value Co-creation that was Described in the Framework. The case Study Indicates Features of Value Co-creation when Implementing Innovation in Organizational Networks.

Genetic Diversity of avrBs-like Genes in Three Different Xanthomonas Species Isolated in Korea

  • Oh, Chang-Sik;Lee, Seung-Don;Heu, Sung-Gi
    • The Plant Pathology Journal
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    • 제27권1호
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    • pp.26-32
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    • 2011
  • Plant-pathogenic bacteria including Xanthomonas spp. carry genetic diversity in composition of avirulence genes for interaction with their host plants. Previously, we reported genetic diversity of avirulence genes in X. axonopodis pv. glycines. In this study, we determined genetic diversity of five avirulence genes, avrBs1, avrBs2, avrBs3, avrBs4, and avrRxv, in three other Xanthomonas species isolated in Korea by genomic southern hybridization. Although Korean races of X. campestris pv. vesicatoria that were isolated from year 1995 to 2002 had the same avirulence gene patterns as those that already reported, there was race shift from race 3 to race 1 by acquisition of avrBs3 genes. X. campestris pv. campestris isolated from Chinese cabbage, but not from cabbage or radish, carried two avrBs3 genes, and one of them affected HR-eliciting ability of this bacterium in broccoli. X. oryzae pv. oryzae carried eight to thirteen avrBs3 gene homologs, and this bacterium showed dynamic changes of resistance patterns in rice probably by losing or obtaining avrBs3 genes. These results indicate that avrBs3 gene is more diverse in Xanthomonas spp. than other four avirulence genes and also host ranges of these bacteria can be easily changed by loss or acquisition of avrBs3 genes.