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机器学习辅助微架构功耗建模和设计空间探索综述

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计算机研究与发展 2024年第6期61卷 1351-1369页

作者：翟建旺凌梓超白晨赵康余备北京邮电大学集成电路学院北京100876 北京邮电大学计算机学院北京100876 香港中文大学计算机科学与工程系中国香港999077

微架构设计是处理器开发的关键阶段,处在整个设计流程的上游,直接影响性能、功耗、成本等核心设计指标.在过去的数十年中,新的微架构设计方案,结合半导体制造工艺的进步,使得新一代处理器能够实现更高的性能和更低的功耗、成本.然而,随... 详细信息

微架构设计是处理器开发的关键阶段,处在整个设计流程的上游,直接影响性能、功耗、成本等核心设计指标.在过去的数十年中,新的微架构设计方案,结合半导体制造工艺的进步,使得新一代处理器能够实现更高的性能和更低的功耗、成本.然而,随着集成电路发展至“后摩尔时代”,半导体工艺演进所带来的红利愈发有限,功耗问题已成为高能效处理器设计的主要挑战.与此同时,现代处理器的架构愈发复杂、设计空间愈发庞大,设计人员期望进行快速精确的指标权衡以获得更理想的微架构设计.此外,现有的层层分解的设计流程极为漫长耗时,已经难以实现全局能效最优.因此,如何在微架构设计阶段进行精确高效的前瞻性功耗估计和探索优化成为关键问题.为了应对这些挑战,机器学习技术被引入到微架构设计流程中,为处理器的微架构建模和优化提供了高质量方案.首先介绍了处理器的主要设计流程、微架构设计及其面临的挑战,然后阐述了机器学习辅助集成电路设计,重点在于使用机器学习技术辅助微架构功耗建模和设计空间探索的研究进展,最后进行总结展望.

关键词：处理器设计自动化微架构设计功耗建模设计空间探索机器学习

基于IQPSO-EKF的多传感器融合姿态测量方法研究

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机电工程 2024年第2期41卷 353-363页

作者：胡启国王磊马鉴望任渝荣重庆交通大学机电与车辆工程学院重庆400074

为解决自动化竖井掘进设备的定位调姿精度对竖井、孔桩挖掘效率与质量的影响,提出了一种基于改进量子粒子群(IQPSO)-扩展卡尔曼滤波(EKF)的姿态测量算法,以提高微机电系统(MEMS)传感器测量精度。首先,对MEMS传感器数据进行了预处理(除... 详细信息

为解决自动化竖井掘进设备的定位调姿精度对竖井、孔桩挖掘效率与质量的影响,提出了一种基于改进量子粒子群(IQPSO)-扩展卡尔曼滤波(EKF)的姿态测量算法,以提高微机电系统(MEMS)传感器测量精度。首先,对MEMS传感器数据进行了预处理(除噪、滤波、校准等);然后,参考现有飞行器的坐标系,建立了姿态解算模型,通过姿态角数学模型及运动学分析,构建了EFK状态方程,针对EKF方法参数估计不准确的问题,以分段混沌映射优化初始种群,引入平均位置最优值来避免陷入局部最优的IQPSO-EFK算法,优化EKF的系统、测量噪声的协方差参数;最后,对改进算法和三组姿态误差估计进行了对比实验。研究结果表明:对比三种典型目标函数,IQPSO-EFK相较于普通粒子群算法(QPSO-EFK)具有更强的寻优能力与收敛精度;对比三组旋转速度姿态测量误差,基于IQPSO-EKF算法的姿态测量方法在测量误差时比真实测量误差减少了约86.3%,比扩展卡尔曼滤波减少了约68.7%,比普通粒子群算法减少了约28.2%,证明该算法有效地提高了MEMS传感器测量精度。

关键词：竖井掘进角度测量仪器姿态测量微机电系统传感器多传感器融合改进量子粒子群-扩展卡尔曼滤波

Image Magnification Method Using Joint Diffusion

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Journal of Computer Science & Technology 2004年第5期19卷 698-707页

作者： Zhong-XuanLiu Hong-jianwang Si-LongPeng InstituteofAutomation TheChineseAcademyofSciencesBeijing100080P.R.China

In this paper a new algorithm for image magnification is presented. Because linear magnification/interpolation techniques diminish the contrast and produce sawtooth effects, in recent years, many nonlinear interpolation methods, especially nonlinear diffusion based approaches, have been proposed to solve these problems. Two recently proposed techniques for interpolation by diffusion, forward and backward diffusion (FAB) and level-set reconstruction (LSR), cannot enhance the contrast and smooth edges simultaneously. In this article, a novel Partial Differential Equations (PDE) based approach is presented. The contributions of the paper include: firstly, a unified form of diffusion joining FAB and LSR is constructed to have all of their virtues; secondly, to eliminate artifacts of the joint diffusion, soft constraint takes the place of hard constraint presented by LSR; thirdly, the determination of joint coefficients, criterion for stopping time and color image processing are also discussed. The results demonstrate that the method is visually and quantitatively better than Bicubic, FAB and LSR.

关键词： image magnification nonlinear diffusion joint diffusion forward-and-backward diffusion level-set reconstruction

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中国特有植物水松的主要营养成分分析

广西科学 2024年第1期31卷 167-174页

作者：徐坚旺唐健民邹蓉韦霄蒋运生韦记青桂林医学院药学院广西桂林541004 广西壮族自治区中国科学院广西植物研究所广西植物功能物质与资源持续利用重点实验室广西桂林541006

为探究水松(Glyptostrobus pensilis)叶和枝的营养价值和开发潜力,本研究提取并分析水松叶和枝的基本营养物质、矿质元素和氨基酸含量,并对其氨基酸营养价值进行分析、评价。结果显示:(1)除蛋白质含量为水松枝比叶高外,干物质、灰分、... 详细信息

为探究水松(Glyptostrobus pensilis)叶和枝的营养价值和开发潜力,本研究提取并分析水松叶和枝的基本营养物质、矿质元素和氨基酸含量,并对其氨基酸营养价值进行分析、评价。结果显示:(1)除蛋白质含量为水松枝比叶高外,干物质、灰分、粗纤维、总黄酮、维生素E以及维生素C均为叶中含量较高。(2)叶和枝中均检测出16种氨基酸,其中有7种必需氨基酸。枝的异亮氨酸和亮氨酸含量高于叶。(3)叶的必需氨基酸比值系数分(Score of Ratio Coefficient of Essential Amino Acid,SRC)比枝高,为64.952,表明叶中氨基酸营养价值较枝高。(4)常量元素中的K、Ca、N含量在水松叶和枝中较高,其中Ca的含量在叶和枝中均最高,并且叶的Ca含量高于枝,为7980.00 mg/kg。(5)微量元素中的Al、Fe含量在水松叶和枝中较高,叶中Al、Zn含量均高于枝的含量,分别为19.700和1.180 mg/kg;枝中Fe含量高于叶含量,为26.700 mg/kg。本研究分析了水松叶和枝中营养成分的特点,为水松作为木本饲料和水松衍生产品开发提供了基础资料。

关键词：水松营养成分氨基酸矿质元素枝和叶

Structure of the Phytoplankton Community and Its Relationship to Water Quality in Donghu Lake, Wuhan, China

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Journal of Integrative Plant Biology 2005年第1期47卷 27-37页

作者： An-PingLEI Zhang-LiHU jianwang Zhi-XinSHI Fung-YeeNoraTAM CollegeofLifeSciences ShenzhenUniversityShenzhen518060China InstituteofHydrobiology theChineseAcademyofSciencesWuhan430072China DepartmentofBiologyandChemistry CityUniversityofHongKongHongKongChina

: The phytoplankton community structure, in terms of species composition, total standing crop, and abundance of the dominant algal species, at four stations in Donghu Lake, Wuhan, China, was investigated monthly from January 1994 to December 1996. A total of 260 taxa was observed, of which Chlorophyta (106 taxa) contributed the highest portion of the total number of taxa, followed by Bacillariophyta (82 taxa) and Cyanophyta (32 taxa). The total standing crop measured by means of chlorophyll a content, cell density, and cell biovolume, as well as the abundance of the dominant species, declined in the order of Station I to Station IV. Seasonal changes of the standing crop varied greatly among the four stations. Although the cell density at the four stations showed a single peak within a year, the peak density varied from July to November, dependent on the sampling year and the station. For chlorophyll a content and cell biovolume, multiple peaks were observed at Stations I and II, but a single peak was found at Stations III and IV. The phytoplankton community structure indicated that the trophic status was the highest at Station I (most eutrophic), followed by Station II; Stations III and IV were the least trophic areas. The long-term changes in phytoplankton community structure further suggested that changes in phytoplankton community structure were correlated with water quality, and eutrophication of Donghu Lake had been aggravated since the 1950s.

关键词： dominant groups eutrophication Donghu Lake phytoplankton species composition standing crop

Selective Oxidation of Propane by Lattice Oxygen of Vanadium-Phosphorous Oxide in a Pulse Reactor

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Journal of Natural Gas Chemistry 2005年第2期14卷 88-94页

作者： RusongZhao jianwang QunDong JianhongLiu CollegeofChemistryandChemicalEngineering BeijingPetrochemicalInstituteBeijing102617China CollegeofChemistryandChemicalEngineering DaqingPetroleumInstituteDaqing163318China

Selective oxidation of propane by lattice oxygen of vanadium-phosphorus oxide(VPO) catalysts was investigated with a pulse reactor in which the oxidation of propane and there-oxidation of catalyst were implemented alternately in the presence of water vapor. The principalproducts are acrylic acid (AA), acetic acid (HAc), and carbon oxides. In addition, small amounts ofC_1 and C_2 hydrocarbons were also found, molar ratio of AA to HAc is 1.4-2.2. The active oxygenspecies are those adsorbed on catalyst surface firmly and/or bound to catalyst lattice, i.e. latticeoxygen; the selective oxidation of propane on VPO catalysts can be carried out in a circulatingfluidized bed (CFB) riser reactor. For propane oxidation over VPO catalysts, the effects of reactiontemperature in a pulse reactor were found almost the same as in a steady-state flow reactor. Thatis, as the reaction temperature increases, propane conversion and the amount of C_1+C_2 hydrocarbonsin the product increase steadily, while selectivity to acrylic acid and to acetic acid increaseprior to 350℃ then begin to drop at temperatures higher than 350℃, and yields of acrylic acid andof acetic acid attained maximum at about 400℃. The maximum yields of acrylic acid and of aceticacid for a single-pass are 7.50% and 4.59% respectively, with 38.2% propane conversion. When theamount of propane pulsed decreases or the amount of catalyst loaded increases, the conversionincreases but the selectivity decreases. Increasing the flow rate of carrier gases causes theconversion pass through a minimum but selectivity and yields pass through a maximum. In a fixed bedreactor, it is hard to obtain high selectivity at a high reaction conversion due to the furtherdegradation of acrylic acid and acetic acid even though propane was oxidized by the lattice *** catalytic performance can be improved in the presence of excess propane. Propylene can beoxidized by lattice oxygen of VPO catalyst at 250℃, nevertheless, selectivity to AA and

关键词： propane oxidation acrylic acid acetic acid vanadium-phosphorus oxide lattice oxygen oxidation pulse reaction

前交叉韧带损伤关节镜下重建术中保留残端与清除残端的前瞻性对照研究

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中国中医骨伤科杂志 2024年第6期32卷 62-67页

作者：周晓武李健旺朱伟民钟名金深圳市龙岗区第五人民医院广东深圳518111 深圳市第二人民医院

目的:采用前瞻性对照研究方法探讨关节镜下前交叉韧带(ACL)损伤重建术中保留残端与清除残端的临床应用价值。方法:前瞻性选取2020年1月至2022年6月ShermanⅠ型前交叉韧带损伤患者102例,按照随机数字表法分组,各51例。均行关节镜下前交... 详细信息

目的:采用前瞻性对照研究方法探讨关节镜下前交叉韧带(ACL)损伤重建术中保留残端与清除残端的临床应用价值。方法:前瞻性选取2020年1月至2022年6月ShermanⅠ型前交叉韧带损伤患者102例,按照随机数字表法分组,各51例。均行关节镜下前交叉韧带重建术,术中保留残端的51例患者作为保留组,术中清除残端的51例患者作为清除组。比较两组术后疼痛视觉模拟量表(VAS)评分、手术前后膝关节功能、膝关节稳定性(KT-2000评分、Berg平衡量表(BBS)评分)、本体感觉(屈曲15°,45°,75°关节位置感觉测定值(JPS))及并发症发生情况。结果:两组术后24 h、48 h、72 h VAS评分较术前下降,保留组低于清除组,差异均有统计学意义(P<0.05);两组术后1个月、3个月、6个月膝关节活动度、Lysholm评分、IKDC评分、KT-2000、BBS评分较术前升高,保留组高于清除组,差异均有统计学意义(P<0.05);两组术后1个月、3个月、6个月屈曲15°,45°,75°感觉测定值较术前降低,保留组低于清除组,差异均有统计学意义(P<0.05);保留组并发症发生率低于清除组,差异有统计学意义(P<0.05)。结论:ShermanⅠ型前交叉韧带损伤患者关节镜下重建术中保留残端能减轻术后疼痛,改善膝关节活动度、关节功能,增强膝关节稳定性及本体感觉,且并发症较少。

关键词：前交叉韧带损伤关节镜下前交叉韧带重建术保留残端清除残端

核电厂便携式低放废水在线监测设备关键技术探讨

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辐射防护 2024年第4期44卷 349-355页

作者：周建旺尤成懋梅翔杰周克波张素杰尹旺明大亚湾核电运营管理有限责任公司广东深圳518124

结合核电厂的实际情况和需求,梳理了低放废水的特点,明确了其对便携式在线监测设备的技术要求,其中最关键是能同时满足低探测下限(MDAC≤8 Bq/L)和便携性(设备总重≤50 kg)的限制。讨论了测量方式、探测器选型和校准方式等在线监测设备... 详细信息

结合核电厂的实际情况和需求,梳理了低放废水的特点,明确了其对便携式在线监测设备的技术要求,其中最关键是能同时满足低探测下限(MDAC≤8 Bq/L)和便携性(设备总重≤50 kg)的限制。讨论了测量方式、探测器选型和校准方式等在线监测设备的关键技术,对低放废水进行了放射性在线监测,测量方式选择取样式,探测器选择大体积NaI晶体,校准方式选择代表点法。调研了低放废水在线监测设备的研究现状,现有的在线监测设备重量都在200 kg以上,与核电厂的要求之间存在较大的差距,有必要开展同时具备低探测下限和优异便携性的新型在线监测设备的研制。对新型探测器的应用、结构和新型测量方式的发展这三个研究方向给出了建议。最后,从提高探测效率的角度,提出了一种基于环形NaI晶体的新型探测器结构,初步论证了其探测下限和设备总重指标有望满足核电厂的要求。

关键词：核电厂低放废水在线监测设备便携式

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The spin and orbital moment contributions of each element to macroscopic magnetization in Co_(0.9)Fe_(0.1) films

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Chinese Science Bulletin 2006年第16期51卷 1934-1938页

作者： GUO Yuxian WANG Jie LI Honghong XU Pengshou CAI jianwang National Synchrotron Radiation Laboratory University of Science and Technology of China Hefei 230029 China State Key Laboratory of Magnetism Institute of Physics Chinese Academy of Sciences Bejing 100080 China

Co-Fe alloy films have such properties as high saturation magnetization, high Curie tem- perature and low coercive force. It is of importance to study the origin of high saturation magnetization in these alloys. In this paper, we study the spin (ms) and orbital moments (mo) of Fe and Co in the Co0.9Fe0.1 film by using X-ray magnetic circular dichroism (XMCD) and SQUID magnetometry. The ms and mo for Co are 1.58 and 0.31 μB, and for Fe are 1.63 and 0.36 μB respectively. The average magnetic moment (1.90 μB) determined by XMCD is in agreement with that obtained from SQUID measurements. The total magnetic moment ratio of Fe to Co is 10.5:89.5, while the ratio of the spin to orbital moment is 83.4:16.6. Considering the separation of the spin and orbital moment, an outcome of mFe-spin : mFe-orbit : mCo-spin : mCo-orbit = 8.6:1.9:74.8:14.7 is obtained.

关键词： XMCD Co-Fe合金自旋矩轨道矩电子结构