• 제목/요약/키워드: branch

검색결과 6,867건 처리시간 0.034초

Estimation Model and Vertical Distribution of Leaf Biomass in Pinus sylvestris var. mongolica Plantations

  • Liu, Zhaogang;Jin, Guangze;Kim, Ji Hong
    • 한국산림과학회지
    • /
    • 제98권5호
    • /
    • pp.576-583
    • /
    • 2009
  • Based on the stem analysis and biomass measurement of 36 trees and 1,576 branches in Pinus sylvestris var. mongolica (Mongolian pine) plantations of Northeast China, this study was conducted to develop estimation model equation for leaf biomass of a single tree and branch, to examine the vertical distribution of leaf biomass in the crown, and to evaluate the proportional ratios of biomass by tree parts, stem, branch, and leaf. The results indicated that DBH and crown length were quite appropriate to estimate leaf biomass. The biomass of single branch was highly correlated with branch collar diameter and relative height of branch in the crown, but not much with stand density, site quality, and tree height. Weibull distribution function would have been appropriate to express vertical distribution of leaf biomass. The shape parameters from 29 sample trees out of 36 were less than 3.6, indicating that vertical distribution of leaf biomass in the crown was displayed by bell-shaped curve, a little inclined toward positive side. Apparent correlationship was obtained between leaf biomass and branch biomass having resulted in linear function equation. The stem biomass occupied around 80% and branch and leaf made up about 20% of total biomass in a single tree. As the level of tree class was increased from class I to class V, the proportion of the stem biomass to total biomass was gradually increased, but that of branch and leaf became decreased.

고주파열응고술을 이용한 척수신경 후내측지 신경절제술에서 후내측지를 확인하는 새로운 기준 -증례 보고- (A New More Reliable Indicator for Confirmation of the Medial Branch in Radiofrequency Neurotomy -Case report-)

  • 신근만;최상은;윤선혜;임소영;정배희;이기헌;홍순용;최영룡
    • The Korean Journal of Pain
    • /
    • 제13권2호
    • /
    • pp.242-246
    • /
    • 2000
  • Radiofrequency medial branch neurotomy is an effective way of controlling pain in the posterior compartment of the spine such as the facet joint, and the interspinous ligament. However, it is difficult to determine the exact location of the medial branch. Up until now we have relied on sensory response provoked by 50 Hz stimulation. The responses elicited using this method are quite subjective and can originate from sources other than the medial branch such as the periosteum, the intermediate or lateral branch. We need a confirmed indicator to locate the medial branch reliably. We applied 2 Hz stimulation under 0.4 volts to locate the medial branch and elicited a motor response. Twitching of multifidus and muscles around the SI joint was observed. The observation of these muscles provides a much more reliable method for confirmation of the medial branch. We have treated 45 chronic nonspecific low back pain patients using radiofrequency medial branch neurotomy with this method of confirming the medial branch.

  • PDF

4-Way 캐쉬의 선택된 Element를 이용한 향상된 동적 분기 예측기 구현 (An Improved Dynamic Branch Predictor by Selective Access of a Specific Element in 4-Way Cache)

  • 황인성;황선영
    • 한국통신학회논문지
    • /
    • 제38A권12호
    • /
    • pp.1094-1101
    • /
    • 2013
  • 본 논문은 4-Way 캐쉬의 선택된 element만을 사용하여 어플리케이션 수행 사이클을 줄인 향상된 동적 분기 예측기를 제안한다. 제안된 동적 분기 예측기는 분기명령어가 페치되면 MRU 버퍼를 참조하여 4-Way 캐쉬의 선택된 element에서 타깃 주소를 얻으므로, 모든 element에 접근하는 기존의 동적 분기 예측기보다 제한된 전력하에서 BTAC entry 수를 증가시킬 수 있어 분기 예측 성공률과 어플리케이션의 수행속도가 상당히 향상된다. 제안된 동적 분기 예측기의 효율성을 SMDL 시스템에 의해 생성된 코어가 벤치마크 어플리케이션을 수행하여 검증한다. 실험결과 동적 분기 예측기가 없는 코어에 비해 생성된 코어의 어플리케이션 수행 사이클은 평균 10.1% 감소하고 어플리케이션의 전력소모는 7.4% 증가한다. 기존 동적 분기 예측기를 사용하는 코어에 비해 수행 사이클은 평균 4.1% 줄어든다.

CPW 구조를 이용한 94 GHz Branch-line 대역통과 여파기의 설계 및 제작 (Design and Fabrication of the 94 GHz Branch-line Bandpass Filter using CPW structure)

  • 권혁자;방석호;이상진;윤진섭;이진구
    • 대한전자공학회논문지SD
    • /
    • 제44권5호
    • /
    • pp.36-41
    • /
    • 2007
  • 본 논문에서는 밀리미터파 대역에서 동작하는 단일 평면 구조의 회로에 쉽게 집적화 할 수 있는 94 GHz CPW branch-line 대역통과 여파기를 설계 및 제작하였다. 본 논문은 커플링 포트들을 open load stub로 연결하고, 격리 포트를 출력노드로 취하여 branch-line 커플러를 transversal filtering section으로 사용하는 것이다. 94 GHz branch-line 대역통과 여파기를 설계하기 위해서 CPW 라이브러리를 구축하고, branch-line 커플러와 open load stub들의 임피던스 및 길이를 최적화하였다. 제작된 대역통과 여파기의 측정결과, 주파수 94 GHz를 중심으로 11.7 %의 3 dB 상대 대역폭과 2.5 dB의 삽입 손실 특성을 나타내었다. 또한, 94 GHz에서 -18.5 dB의 입출력 반사 손실 특성을 얻었다.

멀티프로그래밍 환경에서의 분기 예측 (Branch Prediction in Multiprogramming Environment)

  • 이문상;강영재;맹승렬
    • 한국정보과학회논문지:시스템및이론
    • /
    • 제26권9호
    • /
    • pp.1158-1165
    • /
    • 1999
  • 조건부 분기 명령어(conditional branch instruction)의 잘못된 분기 예측(branch misprediction)은 프로세서의 성능 향상에 심각한 장애 요인이 되고 있다. 특히 시분할(time-sharing) 시스템과 같이 문맥 교환(context switch)이 발생하는 멀티프로그래밍 환경(multiprogramming environment)에서는 더욱 낮은 분기 예측 정확성(branch prediction accuracy)을 보인다. 본 논문에서는 문맥 교환이 발생하는 멀티프로그래밍 환경에서 높은 분기 예측 정확성을 보이는 중첩 분기 예측표 교환(Overlapped Predictor Table Switch, OPTS) 기법을 소개한다. 분기 예측표(predictor table)를 분할하여 각각의 프로세스(process)에 할당하는 OPTS 기법은 문맥 교환의 영향을 최소화함으로써 높은 분기 예측 정확성을 유지하는 분기 예측 방법이다.Abstract There is wide agreement that one of the most important impediments to the performance of current and future pipelined superscalar processors is the presence of conditional branches in the instruction stream. Accurate branch prediction is required to overcome this performance limitation. Many branch predictors have been proposed to help to alleviate this problem, including the two-level adaptive branch predictor, and more recently, hybrid branch predictor. In a less idealized environment, such as a time-sharing system, code of interest involves context switches. Context switches, even at fairly large intervals, can seriously degrade the performance of many of the most accurate branch prediction schemes. In this study, we measure the effect of context switch on the branch prediction accuracy in various situation and show the feasibility of our new mechanism, OPTS(Overlapped Predictor Table Switch), which save and restore branch history table at every context switch.

정확하고 효율적인 간접 분기 예측기 설계 (Design of Accurate and Efficient Indirect Branch Predictor)

  • 백경호;김은성
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2005년도 추계종합학술대회
    • /
    • pp.1083-1086
    • /
    • 2005
  • Modern superscalar processors exploit Instruction Level Parallelism to achieve high performance by speculative techniques such as branch prediction. The indirect branch target prediction is very difficult compared to the prediction of direct branch target and branch direction, since it has dynamically polymorphic target. We present a accurate and hardware-efficient indirect branch target predictor. It can reduce the tags which has to be stored in the Indirect Branch Target Cache without a sacrifice of the prediction accuracy. We implement the proposed scheme on SimpleScalar and show the efficiency running SPEC95 benchmarks.

  • PDF

간호감독 업무현황에 관한 연구 (A Survey on the Role of Supervisor Nurse)

  • 조원정;김소야자;문희자;양원영;최영희
    • 대한간호
    • /
    • 제19권5호통권108호
    • /
    • pp.39-49
    • /
    • 1980
  • The survey was performed with supervisor nurse at 30 general hospitals which had a system in concerning about supervisor nurse in seoul from Nov. 15 to Dec. 2, 1979. The findings as follows; 1. Age distribution of the subjects were from 25 to 65, most of

  • PDF

퍼셉트론을 이용한 다중 분기 예측법 (The Multiple Branch Predictor Using Perceptrons)

  • 이종복
    • 전기학회논문지
    • /
    • 제58권3호
    • /
    • pp.621-626
    • /
    • 2009
  • This paper presents a multiple branch predictor using perceptrons. The key idea is to apply neural networks to the multiple branch predictor. We describe our design and evaluate it with the SPEC 2000 integer benchmarks. Our predictor achieves increased accuracy than the Bi-Mode and the YAGS multiple branch predictor with the same hardware cost.