• 제목/요약/키워드: Early Branch

검색결과 303건 처리시간 0.033초

분기 명령어의 조기 예측을 통한 예측지연시간 문제 해결 (Early Start Branch Prediction to Resolve Prediction Delay)

  • 곽종욱;김주환
    • 정보처리학회논문지A
    • /
    • 제16A권5호
    • /
    • pp.347-356
    • /
    • 2009
  • 정교한 분기 예측기의 설계는 오늘날의 프로세서 성능 향상에 중요한 역할을 하게 되었다. 분기 예측의 정확도가 더욱 더 중요해 지면서 정확도의 향상을 위한 다수의 기법들이 제안되었지만, 기존의 연구들은 예측 지연 시간을 간과하는 경향이 있었다. 본 논문에서는 예측 지연 시간 문제를 해결하고자 조기 예측 기법 (ESP, Early Start Prediction)을 제안한다. 조기 예측 기법은 분기 예측에 있어서 활용되는 분기 명령어의 주소 대신 그것과 일대일 대응이 되는 기본 블록의 시작 주소 (BB_SA, Basic Block Start Address)를 이용한다. 즉, 분기 명령어의 주소가 사용되는 기존의 환경에서, BB_SA를 활용하여 조기 예측을 시작함으로써, 예측 지연 시간을 숨긴다. 또한 제안된 기법은 짧은 간격 숨김 기법(short interval hiding technique)을 통해 보다 더 나은 성능 향상을 기대할 수 있다. 실험 결과 본 논문에서 제안된 기법은 예측 지연 시간을 줄임으로써, 예측 지연 시간이 1 사이클인 이상적인 분기 예측기의 성능에 0.25% 이내로 근접한 IPC 결과를 얻었다. 또한 기본 블록의 시작주소와 분기 명령어 사이에 짧은 간격을 가질 경우에 대한 개선 방법을 추가적으로 적용시킬 경우, 기존의 방식과 비교하여 평균 4.2%, 최대 10.1%의 IPC 향상을 가져왔다.

Effects of Pruning Season on Compartmentalization of Pruning Wounds in Acer palmatum and Pinus strobus

  • Lee, Kyu-Hwa;Lee, Kyung-Joon
    • 한국산림과학회지
    • /
    • 제99권2호
    • /
    • pp.226-234
    • /
    • 2010
  • This study was conducted to examine the effects of pruning season on the compartmentalization of pruning wounds in Acer palmatum and Pinus strobus. A total of eighty five field-grown trees for each species were allocated to five different seasons, early- and late-winter, mid-spring, mid- and late-summer, for pruning treatments. Wound closure rate (WCR) of the two species for one year after treatment, area of discolored stem tissue on the medial longitudinal surface and cambial dieback length under the pruning wound of A. palmatum were measured. Changes of total phenols and variations of extractives, holocellulose and lignin at the treated branch unions were examined. In WCR of A. palmatum, late-winter (March, 39.8%) and mid-spring (May, 39.7%) were higher than any other seasons, while early-winter (November, 28.4%) was significantly lower than late-winter and mid-spring. P. strobus showed similar results with A. palmatum. The WCR of early-winter (57.2%) was the lowest significantly among the five seasons, and mid-spring (73.5%) and late-winter (71.4%) showed higher a WCR than other seasons. In the discolored/wound area ratio of A. palmatum, early-winter (73.2%) was the highest by far, and mid- (July) and latesummer (September, 36.7%, respectively) were the lowest among the five seasons. In the length of cambial dieback, two dormant seasons, early- and late-winter were longer than any other seasons. Phenol contents at the treated branch union were changed in line with the seasonal fluctuation of the tree. Total phenols in the below core of the treated union were higher than those of the branch union with living branch, while little differences were seen in the above core. At the branch core of the treated union, phenols of A. palmatum decreased one month after the treatments, but P. strobus maintained similar to or a little higher than those at the controls. The major changes in chemical composition at pruning wounds were extractives and lignin increased by less than 20% in A. palmatum, while extractives in P. strobus remarkably increased by 70%.

Branch and Bound Approach for Single-Machine Sequencing with Early/Tardy Penalties and Sequence-Dependent Setup Cost

  • Akjiratikarl, Chananes;Yenradee, Pisal
    • Industrial Engineering and Management Systems
    • /
    • 제3권2호
    • /
    • pp.100-115
    • /
    • 2004
  • The network representation and branch and bound algorithm with efficient lower and upper bounding procedures are developed to determine a global optimal production schedule on a machine that minimizes sequence-dependent setup cost and earliness/tardiness penalties. Lower bounds are obtained based on heuristic and Lagrangian relaxation. Priority dispatching rule with local improvement procedure is used to derive an initial upper bound. Two dominance criteria are incorporated in a branch and bound procedure to reduce the search space and enhance computational efficiency. The computational results indicate that the proposed procedure could optimally solve the problem with up to 40 jobs in a reasonable time using a personal computer.

Early Stages in Morphogenesis of the Shell of Crenella decussata (Bivalvia: Mytilidae)

  • Kolotukhina, N.K.;Kulikova, V.A.;Evseev, G.A.
    • 한국패류학회지
    • /
    • 제27권2호
    • /
    • pp.91-97
    • /
    • 2011
  • This study examines the morphological features of larval and postlarval shells of the paedomorphic bivalve Crenella decussata Montagu, 1808 from the Sea of Japan. During the early morphogenesis of the shell of C. decussata the following characteristics appear: prodissoconch I -the anterior and posterior provincular teeth, a broad primary ligament pit located on the chondrophore; nepioconch - the anterior and posterior juvenile teeth,primary lateral teeth, fine commarginal and radial sculpture. Larvae of C. decussata distinctly differ from other mytilid larvae by a D-shaped shell, absence of umbo, astraight hinge margin, and homogeneous fine-grained sculpture without co-marginal lines of growth. These shell characters indicate lecithotrophic development of this species. Some morphostructures are revealed which might be used in crenellin taxonomy.

이식시기가 잔디 생장에 미치는 영향 (Study on the Transplanting Methods of Raising Turf seedling from Seedling Tray; III. Effects of Turf Growth to Transplanting Times)

  • 이명선;임상철
    • 한국자원식물학회지
    • /
    • 제18권1호
    • /
    • pp.194-197
    • /
    • 2005
  • 본 시험은 한국잔디의 실생묘 이식 재배에 따른 적정 이식 시기를 구명하기 위해 수행하였다. 정식시기가 지연됨에 따라 잔디의 생육저하를 초래하였고, 생육특성을 고려할 때, 이식 시기는 7월 초순이전에 하는 것이 좋은 것으로 나타났다. 단일 조건이 지속되는 7월4일 이후부터 정식 묘의 포복 분지경수를 비롯한 마디수, 포복경의 총길이 등에서 급격한 생장 감소 현상을 나타냈다. 특히 제2직립경부터는 포복 분지 경수의 감소를 초래하였다.

History of Minimally Invasive Surgery for Gastric Cancer in Korea

  • Kim, Young-Woo;Yoon, Hong-Man;Eom, Bang-Wool;Park, Ji-Yeon
    • Journal of Gastric Cancer
    • /
    • 제12권1호
    • /
    • pp.13-17
    • /
    • 2012
  • Laparoscopic gastrectomy was begun in 1995 in Korea. But, there was 4 years gap to reactivate in 1999. High incidence of gastric cancer and increasing proportion of early cancer through national screening program along with huge effort and enthusiasm of laparoscopic gastric surgeon, and active academic exchange with Japanese doctors contributed development of laparoscopic gastrectomy in Korea. Study group activity of Korean Laparoscopic Gastrointestinal Surgery Study (KLASS) group and Collaborative Action for Gastric Cancer (COACT) group were paramount to evoke large scale multicenter clinical study and various well performed clinical studies. This review encompasses mainly international publications about this area so far in Korea.