• 제목/요약/키워드: Thread mechanism

검색결과 53건 처리시간 0.036초

실제 적용 타당성 탐색을 위한 고전적 상호배제 알고리즘 성능 평가 (A Performance Evaluation on Classic Mutual Exclusion Algorithms for Exploring Feasibility of Practical Application)

  • 이형봉;권기현
    • 정보처리학회논문지:컴퓨터 및 통신 시스템
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    • 제6권12호
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    • pp.469-478
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    • 2017
  • 상호배제는 원래 다중처리기 시스템을 지원하는 운영체제의 경쟁상황 예방 이론에서 출발하였으나, 최근에는 다중코어처리기의 일반화로 그 적용범위가 급격하게 병렬처리 어플리케이션 영역으로 이동되었다. POSIX 스레드, WIN32 스레드, Java 스레드 등이 대표적인 병렬 처리 어플리케이션 개발환경인데, 이들은 각자 고유한 상호배제 메커니즘을 제공하고 있다. 이들 환경에서 성능에 매우 민감한 어플리케이션들은 코딩의 불편함 등 약간의 희생을 감수하더라도 상호배제를 위한 부담 경감을 필요로 할 수 있다. 이 연구에서는 두 스레드 사이에서 Dekker와 Peterson 알고리즘을 플랫폼별로 바쁜 대기와 처리기 양보 형태로 구현하여 각각의 고유 상호배제 메커니즘들과의 성능을 비교하고, 그 알고리즘들의 유용성을 평가한다. 분석 결과 POSIX 및 WIN32 스레드 환경에서 처리기 양보 형 Dekker 알고리즘이 최소 2배에서 최대 70배까지 우수한 것으로 나타나 이 알고리즘의 실용성이 충분한 것으로 확인되었다.

중재 쓰레드와 지연 캐싱에 의한 스퀴드 프록시 서버 성능 향상에 관한 연구 (A Study on Improving SQUID Proxy Server Performance by Arbitral Thread and Delayed Caching)

  • 이대성;김유성;김기창
    • 정보처리학회논문지C
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    • 제10C권1호
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    • pp.87-94
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    • 2003
  • 인터넷 사용자의 폭발적인 증가로 인해 캐시 서버의 사용이 대두되고 있다. 이에 따라 캐시 서버의 성능을 향상시키기 위한 많은 연구들이 진행되었다. 본 논문에서는 캐시 서버의 병목 현상을 유발하는 원인을 분석하고 그에 대한 해결책으로 중재 쓰레드와 지연 캐싱을 제안한다. 중재 쓰레드를 사용함으로써 캐시 서버가 디스크 쓰기 연산 시에 준비된 다중 쓰레드를 탐색해야 하는 문제점을 없애고 즉시 사용자의 서비스 요청에 응답함으로써 보다 빠른 서비스를 제공할 수 있도록 한다. 또한 준비된 다중 쓰레드가 없는 경우에는 지연 캐싱을 이용해 과부하 상태의 디스크 연산을 피하고 큐가 안정화될 때 캐싱을 하도록 하여 시스템이 안정성 있게 동작하도록 하였다. 제안된 캐시 서버는 스퀴드(SQUID) 캐시 서버를 변형하여 구현되었고 실험을 통해 기존 스퀴드 캐시 서버의 성능과 비교한 결과, 응답 시간의 향상을 관찰할 수 있었다.

매선요법의 류마티스 관절염 동물모델을 활용한 실험연구: 체계적 문헌고찰 (Thread Embedding Therapy in Rheumatoid Arthritis: A Systematic Review of Animal Studies)

  • 전푸르메;조혜연;강석윤;한창현
    • Korean Journal of Acupuncture
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    • 제38권3호
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    • pp.122-132
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    • 2021
  • Objectives : This systematic review aims to assess the effectiveness of thread embedding therapy on animal model for rheumatoid arthritis. Methods : Search was conducted in the Cochrane library, MEDLINE (PubMed), EMBASE, the Chinese National Knowledge Infrastructure, Wan-Fang Database, Technology Journal Database, the Korean Studies Information Service System, the Oriental Medicine Advanced Searching Integrated System, the Research Information Sharing Service, the National Digital Science Library, the Korean Traditional Knowledge Portal and the Korea Citation Index. Data were extracted concerning animal model, intervention and rheumatoid arthritis indicator by two independent reviewers. Reporting quality was also evaluated by the ARRIVE (Animal Research: Reporting In Vivo Experiments) guidelines 2.0. Results : One thousand thirty six studies were primarily selected. After screening, 10 studies met the inclusion criteria. 1 study was published 2005, 1 study was published 2010, 1 study was published 2012, 1 study was published 2015, 2 studies were published 2016, 3 studies were published 2017, 1 study was published 2018. The most frequently used acupoints were ST36 and BL23, and were used with an average frequency of 11.8 days. All of these thread embedding therapy studies were effective on behavioral, morphological, immunohistological and hematological indicators to treat of rheumatoid arthritis model. Conclusions : These results demonstrated the effectiveness of thread embedding therapy and suggested the putative mechanism. However, considering the small number of included studies, low reporting quality and differences in study design, further studies with rigorous designs and high reporting quality need to be conducted.

다양한 마이크로쓰레드(Micro thread)의 개수를 가지는 임플란트의 상부구조물 형상과 하중조건에 따른 3차원 유한요소해석을 이용한 하악골의 응력분포에 관한 연구 (Three-dimensional Stress Analysis of Implant Systems with Micro Threads in the Maxillary Bone)

  • 신하식;한종현;이수홍;전흥재
    • 한국정밀공학회지
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    • 제22권3호
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    • pp.179-186
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    • 2005
  • A comparative study of stress distributions in the maxillary bone with three different types of abutment was conducted. Finite element analysis was adopted to determine stress generated in the bone with the different implant systems with micro threads (Onebody type implant, Internal type implant, and External type implant). It was found that the types of abutments and the number of micro threads have significant influence on the stress distribution in the maxillary bone. They were due to the difference in the load transfer mechanism and the size of contact area between abutment and fixture. Also the maximum effective stress in the maxillary bone was increased with increasing inclination angle of load. It was concluded that the maximum effective stress in the bone was the lowest by the internal implant among the maximum effective stresses by other two types of implants and by appropriate number of micro threads, and that the specific number of micro thread was existed to decrease the maximum effective stress in the maxillary bone due to different implant systems and loading conditions.

솔기유형에 따른 손바느질과 재봉질의 봉합강도 (Seam Strength of Hand Sewing and Machine Sewing according to The Seam Type in Korea Costumes)

  • 김정진;장정대
    • 한국의류산업학회지
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    • 제2권2호
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    • pp.146-149
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    • 2000
  • This study has been investigated the comparison of the seam strength of hand sewing with machine sewing using two kinds of sewing thread. On machine sewing, thread is used for sale, on hand sewing, thread is used for every fabric weft yarn. Breaking strength, efficiency and breaking mode of seams were examined under various sewing conditions using three kinds of fabric and three kinds of stitch type. The results obtained are as follows: The seam strength is not affected by sewing mechanism, but affected by a breaking mode : The type of slipped mode has a higher seam strength of hand sewing than that of machine sewing. When fabrics and threads were broken by a higher seam strength of machine sewing than that of hand sewing. Fabrics having low density using plain seam slipped more easily, so seam strength was greatly lesser. Fabrics having higher density had higher to seam strength. We should choose appropriate seams based on production, economy and aesthetics.

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멀티 쓰레드 기반 N-IDS 모델의 설계 및 구현 (A Design and Implementation of N-IDS Model based on Multi-Thread)

  • 주수홍;엄윤섭;김상철;홍승표;이재호
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2003년도 추계종합학술대회
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    • pp.542-547
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    • 2003
  • 많은 해킹 기법의 발전과 해킹 툴 들이 대중화됨으로 인해 기존의 보안 기술만으로는 발전하는 해킹 기술에 대한 문제를 해결할 수 없게 되었다. 이러한 기존 보안 기술을 대체하기 위한 여러 기술이 등장하였는데 IDS가 그 대표적인 기술 중 하나이다. 네트워크 기반 침입 탐지 시스템인 N-IDS는 패킷에서 침입을 탐지하는 실시간 시스템이다. 따라서 패킷을 캡쳐하고 처리하는 능력이 시스템의 성능을 결정하게 되는데 기존의 N-IDS는 그 구조상 패킷의 캡쳐, 처리 후 다음 패킷 캡쳐까지의 시간 지연이 처리할 패킷의 종류에 따라 불규칙하게 발생한다. 기존의 단일 프로세서 구조를 가진 N-IDS로는 불규칙적인 시간 지연 문제를 해결할 수 없으므로 본 논문에서는 파일 소켓 및 멀티 쓰레드 구조를 이용하여 이러한 문제점을 해결하였다.

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고속 탭핑에서의 절삭 특성 해석 (Analysis of Cutting Characteristics in High Speed Tapping)

  • 강지웅;김용규;이돈진;김선호;김화영;안중환
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2000년도 추계학술대회 논문집
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    • pp.243-246
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    • 2000
  • Productivty of tapping has been increasing through the tcchnological advances in synchronization between spindle rotation and feed motion even in the high spindle speed. However, not much researches have been conducted about tapping process because its complicate cutting mechanism. In order ta investigate the characteristics of the tapping process, this paper concentrates on the analysis of curting torque behavior during one cycle of lapping. As one completc thread is performed through the whole chamfer ercuttlng, cutting torque increases highly in chamfer cutting, but smaothly in full thread cutting Functioning of the threads guide. Cutting torque in backward cutting is smaller than in Sorwerd cutting due to only friction farce in against between the tool and workpiece. And torque behavior of a periodic Sine ripple-mark was identified during one revolution of a tap.

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전동식 사출기의 특성파악 및 수명예측 (Characterization and Life Prediction for an Electric Molding Machine)

  • 김정석;홍성원;정필중
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집A
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    • pp.794-799
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    • 2001
  • For the development of an electric molding machine with low energy, high performance, and high reliability, characterization, finite element analysis and fatigue strength analyses were performed. Strain was measured by strain gages bonded on electric molding machine and compared with stress analysis results using I-DEAS. The analyses showed good agreement with test results. By means of the comparison, we could draw an adequate boundary condition for the stress analysis of the components of electric molding machine. Additionally, we could verify the load distribution mechanism among the parts. The life prediction results for tie bar and thread zone showed infinite life.

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금사, 금침, 금주를 중심으로 한 금(金)의 인체 내 매장요법에 대한 연구동향 고찰연구 (A Review of Research Trends in Gold Implantation Therapy Focused on Gold Thread, Gold Needle and Gold Bead)

  • 조대현;아리온치멕;조예은;이상훈;이재동
    • Journal of Acupuncture Research
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    • 제33권1호
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    • pp.79-93
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    • 2016
  • Objectives : The purpose of this study is to explore research trends in gold implantation therapy performed on the animal and human body, through a review of clinical studies focused on gold thread, gold needle and gold bead. Methods : Medical databases, including Pubmed, CENTRAL, MEDLINE, EMBASE, RISS4u, KISTI, OASIS and KTKP, were searched for relevant articles published from their launch to December 31, 2015 using the key word 'gold' with '$thread^*$', '$needle^*$', '$acupuncture^*$', '$wire^*$', '$bead^*$', '$embed^*$', '$implant^*$', or '$insert^*$'. The results were classified into in vivo studies, clinical trials and clinical reports. Analysis of the results was conducted in several research areas, from the identity of studies such as nationality and published year, to the gold preparations-features and implanted locations and to the outcomes that reflect the clinically favorable or adverse effect of gold implantation therapy. Results : A total of 30 studies including 11 in vivo studies, 4 clinical trials and 15 case reports, were found in the search. We observed certain research trends according to the research time, nationality and target indication of the studies. The studies primarily revealed a chronic local inflammatory response which could be a useful mechanism for pain-relief in musculoskeletal diseases and facial rejuvenation. Researches concerning long-term reactions or adverse effects were rare. Conclusion : The results show that the efforts to discover the level of clinical efficacy of gold implantation therapy were steady and worldwide. However, further researches on the longterm effect, and more importantly, the safety of gold implantation therapy are required.