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Adventures Beyond Amdahl's Law:How Power-Performance Measurement and Modeling at Scale Drive Server and Supercomputer Design

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Journal of Computer Science & Technology 2023年第1期38卷 80-86页

作者： Kirk w.Cameron Computer Science Virginia TechWashington D.C.VA 24061U.S.A.

Amdahl’s Law painted a bleak picture for large-scale *** implication was that parallelism was limited and therefore so was potential *** Amdahl’s contribution was seminal and important,it drove others vested in parallel processing to define more clearly why large-scale systems are critical to our future and how they fundamentally provide opportunities for speedup beyond Amdahl’s *** the early 2000s,much like Amdahl,we predicted dire consequences for large-scale systems due to power *** our early work was often dismissed,the implications were clear to some:power would ultimately limit *** this retrospective,we discuss how power-performance measurement and modeling at scale led to contributions that have driven server and supercomputer design for more than a *** the influence of these techniques is now indisputable,we discuss their connections,limits and additional research directions necessary to continue the performance gains our industry is accustomed to.

关键词： Amdahl’s Law speedup power-aware computing power modeling performance modeling performance prediction power measurement

Validation of VO<sub>2Peak</sub>and performance using a SciFit<sup>TM</sup>Arm Ergometer

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Open Journal of Therapy and Rehabilitation 2014年第1期2卷 33-37页

作者： James A. Yaggie w. Jeffrey armstrong Ian K. Ratz Stephen J. McGregor Applied Physiology Laboratory Eastern Michigan University Ypsilanti USA Department of Health & Physical Education Western Oregon University Monmouth USA Department of Health and Human Performance The University of Findlay Findlay USA

For individuals with lower extremity injury or disability, upper body exercise provides a mechanism of functional mobility training, car-diovascular fitness, as well as a means for clinical fitness assessment. However, the validity of fitness assessment relies on the efficacy of di-agnostic tools and measures in order to provide meaningful data to clinicians. The purpose of this investigation was to determine if the SciFitTMPro II Arm Ergometer, a widely available upper body ergometer (UBE), is a reliable device for the determination of VO2Peak in fit able-bodied swimmers. Eight trained male swimmers (28 ± 9 yrs) performed two incremental protocols VO2Peak consisting of a 4-min warm-up at 15 w followed by 2 min at 50 w and progressing 10 w every 2 min until volitional exhaustion. There was a linear relationship between workload and VO2 in all trials (R = 0.96;p ≤ 0.01) while Cronbach’s alpha for test-retest reliability for VO2 was 0.98. In conclusion, the UBE is an accurate and reliable device for determination of VO2Peak in trained swimmers, and further may be a viable alternative trainingVO2Peak injured athlete.

关键词： Reliability Validity Upper Body Ergometry Swimmers

Exposure to the sun:Harmful or healthy?

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Exposure to the sun:Harmful or healthy?

北京论坛（2005）文明的和谐与共同繁荣——全球化视野中亚洲的机遇与发展

作者： Bruce K armstrong School of Public Health The University of Sydney

At some time in their history,most peoples have revered the sun for its life-giving properties. Most probably still view the sun as a benign *** is not true now,though,of many European populations in which a rising incidence of melanoma of the skin,the most fatal of skin cancers,has seen the rise of a strong movement towards sun *** creed is neatly

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阴山东段先寒武变质岩的Rb-Sr年代

地质科学 1987年第3期3卷 258-264页

作者：孙荣圭,Richard Lee armstrong,孙大中,韩光北京大学地质学系不列颠哥伦比亚大学地质科学系天津地质矿产研究所天津地质矿产研究所

采自阴山东段先寒武变质岩的全岩样品给出四个等时线年龄。下部集宁群为2497±124Ma;上部乌拉山群为2367±127Ma;上部二道洼群给出两个年龄:2067±39Ma和325±16Ma。据此认为,2.5Ga前发生了麻粒岩化;2.35Ga前发生混合岩化;2.0Ga和0.33G... 详细信息

采自阴山东段先寒武变质岩的全岩样品给出四个等时线年龄。下部集宁群为2497±124Ma;上部乌拉山群为2367±127Ma;上部二道洼群给出两个年龄:2067±39Ma和325±16Ma。据此认为,2.5Ga前发生了麻粒岩化;2.35Ga前发生混合岩化;2.0Ga和0.33Ga前有变质事件叠加。

关键词：阴山先寒武铷-锶年代

Biological and historical overview of Zika virus

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world Journal of Virology 2017年第1期6卷 1-8页

作者： Najealicka armstrong wangheng Hou Qiyi Tang Deparment of Microbiology Howard University College of Medicine

The recent outbreak of the Zika virus attracts worldwide attention probably because the most recently affected country(Brazil) will host the 2016 Olympic Game. Zika virus infected cases are now spreading to many other countries and its infection might be linked to some severe medical sequelae. Since its first isolation from the infected monkey in 1947 in Uganda, only a few studies had been taken until recent outbreak. According to the history of referenced publications, there is a 19-year gap from 1989 to 2007. This might be because only mild diseases were diagnosed from Zika virus infected populations. Obviously, the recent reports that Zika virus infection is probably associated with microcephaly of the neonates makes us reevaluate the medical significance of the viral pathogen. It can be transmitted sexually or by mosquito biting. Sexual transmission of the Zika virus distinguishes it from other members of the Genus Flavivirus. Detailed information of the Zika virus is needed through a thorough investigation covering basic, epidemical, subclinical and clinical studies. Here, we reviewed the published information of Zika virus.

关键词： Zika virus Flavivirus Congenital infection Outbreak Microcephaly

An Instrument Variable Model of the Impact of Financing Decisions on Performance of Small Businesses in Australia＇s Pre-global Financial Crisis

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Journal of Modern Accounting and Auditing 2012年第7期8卷 1052-1065页

作者： LI Yongqiang Anona armstrong Andrew Clarke Victoria University Melbourne Australia

Firm level empirical research on the impact of financing decisions on small business performance is scarce in the Australian context. This study adopts an instrument variable （IV） approach to analyze the impact of financing decisions, in particular, equity or debt are obtained, on the performance of small businesses by using the panel data from Australian Bureau of Statistics （ABS） Business Longitudinal Database （BLD） 2004-2005, 2005-2006, and 2006-2007. Performance variables, i.e., sales and expenditure, are used as dependent variables. Equity and debt obtained are used as independent variables （or known as treatments）. IV includes size of the business, age of the business, number of locations, and industry division etc.. The results from IV modeling outperformed those obtained from OLS （Ordinary Least Squares）. Findings include：（1） financing has significantly positive impacts on the performance of small businesses in Australia; （2） equity and debt financing are used as alternatives, comparatively, equity financing is preferred; （3） capital purchases are largely funded by debt financing, while non-capital purchases and salary expenses are funded by equity financing; and （4） equity financing is more often used by firms with increasing capital purchases and declining non-capital purchases, while debt financing is used by firms with the opposite trends. The paper concludes with a discussion of the limitations of this research and future research＇s directions.

关键词： equity financing debt financing small business performance empirical study

Limits on light emission from silicon

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Chinese Optics Letters 2009年第4期7卷 268-270页

作者： Peter würfel Institut für Angewandte Physik Universitt KarlsruheD-76128 KarlsruheGermany

Although silicon is an indirect semiconductor, light emission from silicon is governed by the same gener- alized Planck＇s radiation law as the emission from direct semiconductors. The emission intensity is given by the absorptance of the volume in which there is a difference of the quasi Fermi energies. A difference of the Fermi energies may result h＇om the absorption of external light （photoluminescence） or from the injection of electrons and holes via selective contacts （electroluminescence）. The quantum efficiency may be larger than 0.5 for carrier densities below 10^15 cm^-3. At larger densities, non-radiative recombination, in particular Auger recombination dominates. At all carrier densities, the relation between emission intensity and difference of the quasi Fermi energies is maintained. Since this difference is equal to the voltage of a properly designed solar cell, luminescence is the key indicator of material quality for solar cells.

关键词： Carrier concentration Fermi level Light Light emission Photoluminescence Semiconducting silicon Silicon

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Development of a telehealth monitoring service after colorectal surgery:A feasibility study

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world Journal of Gastrointestinal Surgery 2017年第9期9卷 193-199页

作者： Damian D Bragg Helena Edis Sian Clark Simon L Parsons Binoy Perumpalath Dileep N Lobo Charles A Maxwell-armstrong Gastrointestinal Surgery Nottingham Digestive Diseases Centre and National Institute of Health Research(NIHR)Nottingham Biomedical Research CentreNottingham University Hospitals and University of NottinghamQueen’s Medical CentreNottingham NG7 2UHUnited Kingdom

AIM To evaluate the feasibility of a text-messaging system to remotely monitor and support patients after discharge following elective colorectal surgery,within an enhanced recovery *** Florence(FLO) is a National Health Service telehealth solution utilised for monitoring chronic health conditions,such as hypertension,using *** were designed to monitor the well-being,basic physiological observations and any patient-reported symptoms,and provide support messages to patients undergoing colorectal surgery within an enhanced recovery after surgery protocol for 30 d after *** interactions with FLO and physiological readings were recorded and patients were invited to provide *** Over a four-week period,16 out of 17 patients used the FLO telehealth service at *** patients did not receive telephone follow-up at three days,as per our standard protocol,unless they reported being unwell or did not make use of the *** patients were readmitted within 30 d,and two of these were identified as being unwell by FLO prior to *** adverse events attributable to the use of the technology were *** The utilisation of telehealth in the early follow-up of patients who have undergone major colorectal surgery after discharge is *** use of this technology may assist in the early recognition and management of complications after discharge.

关键词： Telehealth Remote monitoring Colorectalsurgery Telephone follow up Readmission

PREDICTION OF CHARACTERISTICS FOR VERTICAL ROUND NEGATIVE BUOYANT JETS IN HOMOGENEOUS AMBIENT

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Journal of Hydrodynamics 2001年第1期13卷 103-110页

作者： Huai, w.X. Li, w. Dep. of River Eng. Coll. of Water Resource Eng. Wuhan 430072 China

The k-Ε turbulence model is used to establish a mathematical model of a vertical round jet with negative buoyancy in a static homogeneous ambient. The hybrid finite analytic method, with a non-uniform staggered grid, is used to calculate the whole flow field. The variations of centerline velocity, density and turbulent kinetic energy along the axial line for a given exit densimetric Froude number are found to converge to single curves under the unified scaling law derived by Chen and Rodi. The profiles of mean velocities, mean density difference and the half-width of negative buoyant jets for velocity and density are given. The calculation confirmed that the maximum height of rise is proportional to M03/4 B0-1/2, where M0 and B0 are the momentum flux and the buoyancy flux at the source, respectively.

关键词： Computer simulation Jets Mathematical models Numerical methods

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