• Title/Summary/Keyword: Branch

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

  • Liu, Zhaogang;Jin, Guangze;Kim, Ji Hong
    • Journal of Korean Society of Forest Science
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    • v.98 no.5
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    • pp.576-583
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    • 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.

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

  • Shin, Keun-Man;Choi, Sang-Eun;Yun, Seon-Hye;Lim, So-Young;Jung, Bae-Hee;Lee, Kee-Heon;Hong, Soon-Yong;Choi, Young-Ryong
    • The Korean Journal of Pain
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    • v.13 no.2
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    • pp.242-246
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    • 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.

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

  • Hwang, In-Sung;Hwang, Sun-Young
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38A no.12
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    • pp.1094-1101
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    • 2013
  • This paper proposes an improved branch predictor that reduces the number execution cycles of applications by selectively accessing a specific element in 4-way associative cache. When a branch instruction is fetched, the proposed branch predictor acquires a branch target address from the selected element in the cache by referring to MRU buffer. Branch prediction rate and application execution speed are considerably improved by increasing the number of BTAC entries in restricted power condition, when compared with that of previous branch predictor which accesses all elements. The effectiveness of the proposed dynamic branch predictor is verified by executing benchmark applications on the core simulator. Experimental results show that number of execution cycles decreases by an average of 10.1%, while power consumption increases an average of 7.4%, when compared to that of a core without a dynamic branch predictor. Execution cycles are reduced by 4.1% in comparison with a core which employs previous dynamic branch predictor.

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

  • Kwon, Hyuk-Ja;Bang, Suk-Ho;Lee, Sang-Jin;Yoon, Jin Seob;Rhee, Jin-Koo
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.44 no.5
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    • pp.36-41
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    • 2007
  • We report the 94 GHz CPW branch-line bandpass filter for planar integrated millimeter-wave circuits. The branch-line coupler operates as a transversal filtering section by connecting the coupling ports to the open load stubs and taking the isolation port as the output node. For design of the 94 GHz branch-line bandpass filter, we built the CPW library and optimized the characteristic impedances and the lengths of the branch-line coupler and the open load stubs. The fabricated 94 GHz bandpass filter exhibits an insertion loss of 2.5 dB with an 11.7 % 3 dB relative bandwidth and the return loss is -18.5 dB at a center frequency of 94 GHz.

Branch Prediction in Multiprogramming Environment (멀티프로그래밍 환경에서의 분기 예측)

  • Lee, Mun-Sang;Gang, Yeong-Jae;Maeng, Seung-Ryeol
    • Journal of KIISE:Computer Systems and Theory
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    • v.26 no.9
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    • pp.1158-1165
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    • 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.

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

  • Paik, Kyoung-Ho;Kim, Eun-Sung
    • Proceedings of the IEEK Conference
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    • 2005.11a
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    • pp.1083-1086
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    • 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.

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

  • Jo Won Jeong;Kim So Ya Ja;Moon hee ja;Yang Won Yeong;Choe Yeong Hui
    • The Korean Nurse
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    • v.19 no.5 s.108
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    • pp.39-49
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    • 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

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

  • Lee, Jong-Bok
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.3
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    • pp.621-626
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    • 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.