• 제목/요약/키워드: branch history

검색결과 210건 처리시간 0.034초

내장형 프로세서를 위한 저전력 분기 예측기 설계 기법 (A Power-aware Branch Predictor for Embedded Processors)

  • 김철홍;송성근
    • 정보처리학회논문지A
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    • 제14A권6호
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    • pp.347-356
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    • 2007
  • 프로세서의 파이프라인 길이가 점차 길어지고 한 사이클에 이슈되는 명령어의 수가 증가함에 따라, 분기 예측기의 정확도는 프로세서의 성능에 상당한 영향을 미치게 되었다. 또한, 내장형 프로세서를 설계하는데 있어서는 전력 효율성이 가장 중요한 설계 고려 사항 중 하나가 되었다. 그러므로, 내장형 프로세서의 분기 예측기를 설계할 때에는 성능과 전력 효율성이 함께 고려되어야 한다. 본 논문에서는 gshare 분기 예측기가 적용된 내장형 프로세서에서 선택적인 BTB (Branch Target Buffer) 접근을 가능하게 하는 저전력 분기 예측기를 제안하고자 한다. 제안하는 분기 예측기 내에서 BTB는 직전 명령어가 테이큰 (Taken) 분기로 예측되지 않는 경우에는, PHT (Pattern History Table)의 예측 결과가 테이큰인 경우에만 접근된다. PHT의 예측 결과가 테이큰인 분기 명령어의 경우에만 다음에 인출될 명령어의 주소를 BTB 접근을 통해 얻은 주소로 결정하기 때문이다. 물론, 이와 같은 선택적인 BTB 접근으로 인하여 성능 저하가 발생하는 것을 방지하기 위해 직전 명령어가 테이큰분기로 예측된 경우에는 PHT의 예측 결과에 관계없이 BTB는 항상 접근된다. 선택적인 BTB 접근을 하기 위해, 제안하는 분기 예측기 내의 PHT는 기존 분기 예측기의 PHT와 비교하여 1 사이클 일찍 접근되도록 구현한다. 1 사이클 빠른 접근을 위해 제안하는 PHT는 한 번의 접근을 통해 두 개의 예측 결과를 동시에 얻어오게 구현하고, 이를 통해 PHT의 접근 횟수도 줄임으로써 분기 예측기의 전력 소모를 줄이는 효과 또한 얻게 된다. 제안하는 분기 예측기는 하드웨어 오버헤드나 예측 정확도의 감소 없이 전력 소모를 줄일 수 있다는 장점을 가진다. 실험 결과에 따르면, 제안하는 분기 예측기는 기존의 분기 예측기와 비교하여 $35{\sim}48%$의 전력 소모를 줄이는 결과를 보인다.

Verification and validation of isotope inventory prediction for back-end cycle management using two-step method

  • Jang, Jaerim;Ebiwonjumi, Bamidele;Kim, Wonkyeong;Cherezov, Alexey;Park, Jinsu;Lee, Deokjung
    • Nuclear Engineering and Technology
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    • 제53권7호
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    • pp.2104-2125
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    • 2021
  • This paper presents the verification and validation (V&V) of a calculation module for isotope inventory prediction to control the back-end cycle of spent nuclear fuel (SNF). The calculation method presented herein was implemented in a two-step code system of a lattice code STREAM and a nodal diffusion code RAST-K. STREAM generates a cross section and provides the number density information using branch/history depletion branch calculations, whereas RAST-K supplies the power history and three history indices (boron concentration, moderator temperature, and fuel temperature). As its primary feature, this method can directly consider three-dimensional core simulation conditions using history indices of the operating conditions. Therefore, this method reduces the computation time by avoiding a recalculation of the fuel depletion. The module for isotope inventory calculates the number densities using the Lagrange interpolation method and power history correction factors, which are applied to correct the effects of the decay and fission products generated at different power levels. To assess the reliability of the developed code system for back-end cycle analysis, validation study was performed with 58 measured samples of pressurized water reactor (PWR) SNF, and code-to-code comparison was conducted with STREAM-SNF, HELIOS-1.6 and SCALE 5.1. The V&V results presented that the developed code system can provide reasonable results with comparable confidence intervals. As a result, this paper successfully demonstrates that the isotope inventory prediction code system can be used for spent nuclear fuel analysis.

양생의학 연구의 회고와 전망 (Retrospect on Preventive Medicine Research and its Future)

  • 김남일
    • 한국의사학회지
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    • 제29권2호
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    • pp.71-81
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    • 2016
  • This paper discusses the research of preventive medicine in terms of philosophy and history, publication and people, branch research, applied research, Gi-gong, conduction exercise and so on. Currently, fields of philosophy, history, physical education and Korean Medicine are actively participating in the research on preventive medicine. From the philosophical view, theoretical aspects of preventive medicine are closely examined. From the historical view, the historical context is of focus. From the physical education viewpoint, Gi-gong, gymnastics and physical education philosophy are studied. In the field of Korean medicine where practicality is most important, plans to apply preventive medicine to life are creating new possibilities for research on preventive medicine. In this time where social interest on health is at peak, combined research of basic theory and application will have positive effects on the development of preventive medicine.

Review of Neurosurgical Fluorescence Imaging Systems for Clinical Application

  • Kim, Hong Rae;Lee, Hyun Min;Yoo, Heon;Lee, Seung Hoon;Kim, Kwang Gi
    • Journal of the Optical Society of Korea
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    • 제20권2호
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    • pp.305-313
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    • 2016
  • A number of fluorescence imaging techniques for use in the surgical removal of glioma have been developed over the course of the long history of neurosurgery. Various biomarkers, biochemical agents, and detection systems for glioma have also been developed. This review focuses on 5-aminolevulinic acid (5-ALA), which is used to detect glioma. Numerous forms of fluorescence-guided surgery use 5-ALA, which is helpful to the surgeon. The surgical microscope system is the observational method generally used with 5-ALA, while the loupe, endoscope, and exoscope are simpler alternatives. A system is needed for minimal resection and other issues that arise during neurosurgery. Such an enhanced system should be able to detect low-grade tumors and provide information on microinvasive diseases, resulting in an improved survival rate and better surgical skills. Development of systems that fulfill certain needs would help protect the brain function of the patient and broaden the use of such systems in neurosurgery.

콜럼부스의 대서양 항해 -항해의 경과와 역사적 의의를 중심으로- (A Case Study focused on Columbus's Sailing - A Study on the European Expansion in the later Middle Age -)

  • 김성준
    • 한국항해학회지
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    • 제21권1호
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    • pp.33-55
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    • 1997
  • The European expansion in the later middle age, as Adam Smith stated, influenced greatly on development of the world history. In the various events of the European expansion the discovery of the New World by Christopher Columbus is very important because the effect of the discovery of the New World have still continued to the present. I have interested to find out the reason why the western civilization has seized on the hegemony of the world over other civilizations. As many scholars pointed out, the most distinguished difference between the western civilization and other civilizations is that the western civilization was maritime-oriented, while other civilization were continental-oriented. So I set up the maritime histoy on the theme of my study in order to ruminate upon meaning of the se-power that is one of the motivating forces to drive histoy. Maritime history is not simply about that is maritime affairs, but a branch of history that inquires into inter-relations between maritime affairs and inland affairs. Maritime history constitutes of history of naval war, history of shipping and history of marine development. As above reasons, I have interested the European expansion in the later middle age that maritime activity was the most vigorous in the history. This is a case study to compose maritime history.

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Analysis of Microsatellite DNA Polymorphisms in Five China Native Cattle Breeds and Application to Population Genetics Studies

  • Jin, Hai-Guo;Zhao, Yu-Min;Zhou, Guo-li
    • Asian-Australasian Journal of Animal Sciences
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    • 제18권12호
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    • pp.1696-1700
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    • 2005
  • Five China native cattle breeds have been characterized by using 10 microsatellite DNA markers. The studied populations can be divided into five groups: Luxi cattle, Nanyang cattle, Jinnan cattle, Qinchuan cattle and Yanbian cattle. Allele frequencies were calculated and used for the characterization of the breeds and the study of their genetic relationships. Heterozygosity, polymorphism information content, the effective number of alleles was calculated. Nei' standard genetic distance (1978) was calculated and used for a neighbor-joining tree construction. NJ tree showed that Luxi cattle, Nanyang cattle, Jinnan cattle and Qinchuan cattle are closely related, whereas Yanbian cattle are clearly distinct from other four populations. The genetic relationship of five breeds corresponds to their history and geographic origins. This work analyzes the recent origin of these populations and contributes to the knowledge and genetic characterization of China native breeds.

Thymidylate Synthase and Dihydropyrimidine Dehydrogenase Levels Are Associated with Response to 5-Fluorouracil in Caenorhabditis elegans

  • Kim, Seongseop;Park, Dae-Hun;Shim, Jaegal
    • Molecules and Cells
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    • 제26권4호
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    • pp.344-349
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    • 2008
  • 5-Fluorouracil (5-FU), a pyrimidine antagonist, has a long history in cancer treatment. The targeted pyrimidine biosynthesis pathway includes dihydropyrimidine dehydrogenase (DPD), which converts 5-FU to an inactive metabolite, and thymidylate synthase (TS), which is a major target of 5-FU. Using Caenorhabditis elegans as a model system to study the functional and resistance mechanisms of anti-cancer drugs, we examined these two genes in order to determine the extent of molecular conservation between C. elegans and humans. Overexpression of the worm DPD and TS homologs (DPYD-1 and Y110A7A.4, respectively) suppressed germ cell death following 5-FU exposure. In addition, DPYD-1 depletion by RNAi resulted in 5-FU sensitivity, while treatment with Y110A7A.4 RNAi and 5-FU resulted in similar patterns of embryonic death. Thus, the pathway of 5-FU function appears to be highly conserved between C. elegans and humans at the molecular level.

Data-driven modeling of optimal intensity measure of soil-nailed wall structures

  • Massoumeh Bayat;Mahdi Bayat;Mahmoud Bayat
    • Structural Engineering and Mechanics
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    • 제86권1호
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    • pp.85-92
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    • 2023
  • This article examines the seismic vulnerability of soil nail wall structures. Detailed information regarding finite element modeling has been provided. The fragility function evaluates the relationship between ground motion intensities and the probability of surpassing a specific level of damage. The use of incremental dynamic analysis (IDA) has been applied to the soil nail wall against low to severe ground motions. In the nonlinear dynamic analysis of the soil nail wall, a set of twenty seismic ground motions with varying PGA ranges are used. The numerical results demonstrate that the soil-nailed wall reaction is extremely sensitive to earthquake ground vibrations under different intensity measures (IM). In addition, the analytical fragility curve is provided for various intensity values.

Comparative Morphology and Seasonality of Campylaephora borealis and C. crassa (Ceramiaceae, Rhodophyta)

  • Seo, Kyung-Suk;Boo, Sung-Min
    • ALGAE
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    • 제20권4호
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    • pp.325-331
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    • 2005
  • Populations of Campylaephora borealis (Nakamura) Seo, Cho et Boo and C. crassa (Okamura) Nakamura show a year-around occurrence of all life-history stages. Such a concurrency of life-history stages produces problems in recognizing species in the field. Here, we invesitgated the morphological variation and life-history stages of both species using a statistical character analysis. Life-history stage was correlated with the seawater temperature in C. borealis, whereas it was dependant on biomass in C. crassa. Thalli had dichotomous branches with adaxial branchlets. The statistics showed that the seasonal change in morphology of C. borealis was significantly different from that of C. crassa in seven qualitative characters and five quantitative characters (p < 0.001), although six quantitative features including tetrasporangial size were similar in both species. The morphological difference between the two species may be due to the annual variation of branchlet number and the variance of branch subangle.