检索结果-南通市图书馆

提高DSSS信号PN码相位测量精度的三点二次插值法

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

通信学报 2007年第2期28卷 130-133页

作者：龚国辉李思昆国防科技大学计算机学院湖南长沙410073

提出了利用三点二次插值法处理相关谱谱峰数据以提高DSSS(直序扩频)信号PN码相位测量精度的算法。该算法利用相关谱谱峰及其邻近的2个数据点确定二次插值多项式,然后求取插值多项式的极大值点以确定相关谱谱峰精确位置,有效地提高DSSS信... 详细信息

提出了利用三点二次插值法处理相关谱谱峰数据以提高DSSS(直序扩频)信号PN码相位测量精度的算法。该算法利用相关谱谱峰及其邻近的2个数据点确定二次插值多项式,然后求取插值多项式的极大值点以确定相关谱谱峰精确位置,有效地提高DSSS信号PN码相位的测量精度。实验结果表明,该算法实现了大幅度提高PN码相位测量精度的目的。

关键词：直序扩频信号 PN码相位测量快速傅立叶变换三点二次插值

在线全文

学校读者我要写书评

暂无评论

微处理器体系结构级测试程序自动生成技术

软件学报 2005年第12期16卷 2172-2180页

作者：朱丹李暾郭阳李思昆国防科学技术大学计算机学院湖南长沙410073

提出了一种由体系结构描述驱动的基于约束求解的微处理器体系结构级测试程序自动生成的新方法,并基于此开发了原型系统——MA2TG(microprocessorarchitecturalautomatictestprogramgenerator).该系统不仅可以随机生成测试程序,最主要的... 详细信息

提出了一种由体系结构描述驱动的基于约束求解的微处理器体系结构级测试程序自动生成的新方法,并基于此开发了原型系统——MA2TG(microprocessorarchitecturalautomatictestprogramgenerator).该系统不仅可以随机生成测试程序,最主要的是可以产生针对特定要求的测试程序.其优点在于:首先,通过体系结构语言描述简化了体系结构建模,方便了对目标处理器体系结构的探索;第二,利用比较成熟的约束求解技术来生成满足需求的测试程序;第三,极大地缩减了测试程序的大小以及微处理器的验证时间.MA2TG已应用于DLX处理器和自主开发的EStar嵌入式微处理器的验证.实验结果表明了此方法的有效性.

关键词：体系结构描述语言约束满足问题指令模板库测试程序生成

Converting an O-vacancy-rich oxide into a multifunctional separator modifier for long-lifespan lithium metal batteries

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第10期97卷 371-378,I0007页

作者： Juntao si Xiaoying li Yixuan li Kuo Cao Yiran Zhu Chunhua Chen CAS Key Laboratory of Precision and Intelligent Chemistry Department of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026AnhuiChina

The lithium metal anode is hailed as the desired "holy grail" for the forthcoming generation of highenergy-density batteries,given its astounding theoretical capacity and low ***,the formation and growth of dendrites seriously compromise battery life and ***,an yttriastabilized bismuth oxide(YSB) layer is fabricated on the polypropylene(PP) separator,where YSB reacts with li anode in-situ in the cell to form a multi-component composite interlayer consisting of li_(3)Bi,li_(2)O,and Y_(2)O_(3).The interlayer can function not only as a redistributor to regulate li^(+) distribution but also as an anion adsorber to increase the li^(+) transference number from 0.37 to 0.79 for suppressing dendrite nucleation and ***,compared with the cell with a baseline separator,those with modified separators exhibit prolonged lifespan in both li/li symmetrical cells and li/Cu ***,the full cells coupled with ultrahigh-loading liFePO_(4) display an excellent cycling performance of 1700 cycles with a high capacity retention of ~80% at 1 C,exhibiting great potential for practical *** work provides a feasible and effective new strategy for separator modification towards building a much-anticipated dendrite-free li anode and realizing long-lifespan lithium metal batteries.

关键词： lithium metal battery Separator Dendrite-free Multifunctional interlayer Conversion-alloying reaction

在线全文

学校读者我要写书评

暂无评论

虚拟战场的实时四声道立体声合成

国防科技大学学报 2000年第4期22卷 45-50页

作者：曾亮李思昆国防科技大学计算机学院湖南长沙410073

面向虚拟战场提出了实现实时四声道立体声合成的简化算法。针对四声道立体声的特殊性 ,首先探讨了四声道立体声系统中扬声器的配置方案。在四声道立体声系统扬声器配置方案的基础上 ,解决了单声源的表示、声强衰减及实时立体声化问题 ,... 详细信息

面向虚拟战场提出了实现实时四声道立体声合成的简化算法。针对四声道立体声的特殊性 ,首先探讨了四声道立体声系统中扬声器的配置方案。在四声道立体声系统扬声器配置方案的基础上 ,解决了单声源的表示、声强衰减及实时立体声化问题 ,然后提出一种评价混声效果的标准及一个评价声源对整个声音所作贡献的公式 ,并由此提出一个混声公式 ,从而解决了多声源环境的实时混声问题。该套算法用于应用系统 ,取得了较好的效果。

关键词：四声道立体声虚拟战场虚拟现实

核心循环到粗粒度可重构体系结构的流水化映射

在线全文

学校读者我要写书评

暂无评论

计算机学报 2009年第6期32卷 1089-1099页

作者：王大伟窦勇李思昆国防科学技术大学计算机学院软件所长沙410073

粗粒度可重构体系结构为数据密集型应用提供了灵活性和高效的解决方法,而应用中的核心循环消耗了程序的大量执行时间,满足核心循环在CGRAs上实现的性能/开销的严格约束仍旧是个重大难题.针对已有工作在研究映射核心循环到CGRAs上的不足... 详细信息

粗粒度可重构体系结构为数据密集型应用提供了灵活性和高效的解决方法,而应用中的核心循环消耗了程序的大量执行时间,满足核心循环在CGRAs上实现的性能/开销的严格约束仍旧是个重大难题.针对已有工作在研究映射核心循环到CGRAs上的不足,文中提出一种新颖的核心循环自动流水映射到粗粒度可重构体系结构上的方法.文中形式化了核心循环到CGRAs的流水映射问题,阐述了CGRAs的资源共享和流水方法,定义了其循环自流水CGRAs体系结构模板,并给出核心循环流水映射方法.实验结果表明,与已有的先进的方法相比,文中方法的资源占用率降低16.3%、吞吐量提高169.1%.

关键词：可重构计算粗粒度可重构体系结构数据密集型应用循环自流水

Carbonation of Pure Minerals in Portland Cement:Evolution in Products as a Function of Water-to-solid Ratio

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1214-1222页

作者： XIONG kun SHANG Xiaopeng li Hongyan WANG Dan Zhengzhou Lutong Highway Construction Co. Ltd.Zhengzhou 450052China (Special Glass Key Lab of Hainan Province)&(State Key Laboratory of Marine Resource Utilization in South China Sea) Hainan UniversityHaikou 570228China Department of Architectural Engineering Shandong Urban Construction Vocational CollegeJinan 250103China (State Key Laboratory of High Performance Civil Engineering Materials Jiangsu Sobute New Materials Co.Ltd.)&(School of Material Science and EngineeringSoutheast UniversityNanjing 211189China)

Minerals in Portland cement including tricalcium silicate(C_(3)S),β-dicalcium silicate(β-C_(2)S),tricalcium aluminate(C_(3)A),and tetracalcium ferroaluminate(C_(4)AF),show a significantly different activity and product evolution for CO_(2)curing at various water-to-solid *** pure minerals were synthesized and subject to CO_(2)curing in this study to make an in-depth understanding for the carbonation properties of cement-based *** showed that the optimum water-to-solid ratios of C_(3)S,β-C_(2)S,C_(3)A and C_(4)AF were 0.25,0.15,0.30 and 0.40 for carbonation,corresponding to 2 h carbonation degree of 38.5%,38.5%,24.2%,and 21.9%,*** produced calcite duringβ-C_(2)S carbonation decreased as the water-to-solid ratio increased,with an increase in content of metastable CaCO_(3)of vaterite and *** thermodynamic stability of CaCO_(3)produced during carbonation was C_(3)A>C_(4)AF>β-C_(2)S>C_(3)*** carbonation degree of Portland cement was predicted based on the results of pure minerals and the composition of cement,and the error of predicted production of CaCO_(3)was only 1.1%,which provides a potential method to predict carbonation properties of systems with a complex mineral composition.

关键词： accelerated carbonation portland cement calcium carbonate water-to-solid ratio

面向SoC任务分配的应用程序存储需求量分析方法

在线全文

学校读者我要写书评

暂无评论

电子学报 2010年第3期38卷 541-545页

作者：赵鹏王大伟李思昆国防科技大学计算机学院湖南长沙410073

通过分析应用程序的存储需求量,辅助片上系统(System-on-Chip,SoC)任务分配进行数据存储与传输优化,是改善SoC性能的途径之一.目前,存储需求量分析方法的分析粒度单一、速度缓慢,不利于进行多粒度任务分配空间的高效探索.本文面向SoC任... 详细信息

通过分析应用程序的存储需求量,辅助片上系统(System-on-Chip,SoC)任务分配进行数据存储与传输优化,是改善SoC性能的途径之一.目前,存储需求量分析方法的分析粒度单一、速度缓慢,不利于进行多粒度任务分配空间的高效探索.本文面向SoC任务分配,提出一种多粒度、快速存储需求量分析方法.该方法可进行多粒度的存储需求量分析,并针对多媒体程序,引入数组数据域划分技巧,大幅度减少了存储需求量的分析时间.

关键词：片上系统任务分配存储需求量分析多面体模型

A Novel Fall Detection Framework Using Skip-DSCGAN Based on Inertial Sensor Data

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第1期78卷 493-514页

作者： kun Fang Julong Pan lingyi li Ruihan Xiang College of Information Engineering China Jiliang UniversityHangzhou310018China

With the widespread use of Internet of Things(IoT)technology in daily life and the considerable safety risks of falls for elderly individuals,research on IoT-based fall detection systems has gainedmuch *** paper proposes an IoT-based spatiotemporal data processing framework based on a depthwise separable convolution generative adversarial network using skip-connection(Skip-DSCGAN)for fall *** method uses spatiotemporal data from accelerometers and gyroscopes in inertial sensors as input data.A semisupervised learning approach is adopted to train the model using only activities of daily living(ADL)data,which can avoid data imbalance ***,a quantile-based approach is employed to determine the fall threshold,which makes the fall detection frameworkmore *** proposed fall detection framework is evaluated against four other generative adversarial network(GAN)models with superior anomaly detection performance using two fall public datasets(sisFall&MobiAct).The test results show that the proposed method achieves better results,reaching 96.93% and 92.75% accuracy on the above two test datasets,*** the same time,the proposed method also achieves satisfactory results in terms ofmodel size and inference delay time,making it suitable for deployment on wearable devices with limited *** addition,this paper also compares GAN-based semisupervised learning methods with supervised learning methods commonly used in fall *** clarifies the advantages of GAN-based semisupervised learning methods in fall detection.

关键词： Fall detection skip-connection depthwise separable convolution generative adversarial networks inertial sensor

Advancements in synthetic and electrocatalytic exploitation of guest-host intercalated 2D materials

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2024年第3期34卷 454-469页

作者： Qian Yang kun Wang Meiling Zhang Feihong Du Jiayang li Chen Zheng Jinyang li School of Chemistry Southwest Jiaotong University Yibin Institute of Southwest Jiaotong University

The emergence and development of layered materials have shown great promise for many applications, especially in recent years, the effective modulation of the physicochemical properties of layered materials by intercalation chemistry has led to great potential in material design. In this paper, we review the reaction mechanisms of different guest species(metal atoms/ions, organic molecules/ions, inorganic molecules and inorganic ions)intercalated into the host layered materials as well as the recent progress. It is also reviewed that layered intercalated materials with controllable structure and tunable physicochemical properties can be prepared through the occurrence of interactions between different subjects and guests. The specific applications of intercalation chemistry in the field of electrocatalysis, such as the hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction and other electrocatalytic reactions, are then discussed, with emphasis on the mechanism of the improved catalytic activity and stability of the layered materials after guest intercalation.

关键词： Layered materials Intercalation chemistry Guest species Electrocatalysis