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黄河三角洲附近海域地形测量最佳时段确定 被引量:1
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作者 王万战 吴嫡捷 《人民黄河》 CAS 北大核心 2018年第8期22-26,共5页
为减小黄河三角洲附近海域地形高程测量误差,利用渤海潮汐平面二维数学模型和2015年黄河三角洲附近海域大范围加密地形测量资料等,首先研究了三角洲岸边有、无潮滩对测验断面沿程水位及海底高程计算结果的影响,发现验潮站位于有、无潮... 为减小黄河三角洲附近海域地形高程测量误差,利用渤海潮汐平面二维数学模型和2015年黄河三角洲附近海域大范围加密地形测量资料等,首先研究了三角洲岸边有、无潮滩对测验断面沿程水位及海底高程计算结果的影响,发现验潮站位于有、无潮滩的岸边时,岸边与断面测点同步水位都具有越向深水区差值越大的特点,但是当验潮站位于有潮滩的沟道时,潮滩附近出现陡坎式水面线,岸边与断面测点同步水位差值还会在浅水区出现极大值,岸边与测点同步水位差值最大为1.3 m。基于水位引用造成的断面高程平均误差最小化原则,给出了渤海湾、莱州湾地形测量典型断面最佳测量时段:渤海湾有潮滩的断面最佳测验时段是高潮前、大潮后的低潮前,无潮滩的断面测量则是低低潮前、后和高低潮前、后;莱州湾无潮滩断面最佳测验时段是低低潮与其前、后高高潮之间,有潮滩的断面则是低高潮前、后和高高潮前。最佳测量时段长占一个潮周期的25%~50%,这些时间断面测量平均误差较小,为0.04~0.12 m。 展开更多
关键词 高程误差 潮位 测量时机 海底地形测量 黄河三角洲海域
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全血粘度测量时间探讨 被引量:1
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作者 戴莉莎 朱凤菊 李璐 《中国血液流变学杂志》 CAS 1999年第1期48-49,共2页
关键词 全血粘度 测量时机 血液检测
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浅谈高海拔异型钢结构施工质量控制——湖北神农架机场航站楼工程 被引量:1
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作者 李秀峰 李东浩 李钦 《工程质量》 2013年第S1期181-184,共4页
本工程利用AutoCAD三维技术和Xsteel软件将整个结构在计算机中按现实情况进行虚拟建造。根据确定的安装方案及通用原则将虚拟建成的三维模型拆解,进行节点和构造方面的处理,在钢结构深化时,就充分利用了科技手段把加工和安装的误差消除... 本工程利用AutoCAD三维技术和Xsteel软件将整个结构在计算机中按现实情况进行虚拟建造。根据确定的安装方案及通用原则将虚拟建成的三维模型拆解,进行节点和构造方面的处理,在钢结构深化时,就充分利用了科技手段把加工和安装的误差消除。通过温差测量时机的选择和合理测量方案,对屋面梁安装空间定位精确,使安装过程非常顺利。根据高海拔多雨雾的实际情况,自制防雨棚,有效地解决了雨雾对构件焊接的影响,保证了焊接质量。 展开更多
关键词 高海拔 多雨雾 测量时机 质量控制
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Nonlinear Time Series Prediction Using LS-SVM with Chaotic Mutation Evolutionary Programming for Parameter Optimization 被引量:1
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作者 XU Rui-Rui CHEN Tian-Lun GAO Cheng-Feng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第4期641-646,共6页
Nonlinear time series prediction is studied by using an improved least squares support vector machine (LSSVM) regression based on chaotic mutation evolutionary programming (CMEP) approach for parameter optimizatio... Nonlinear time series prediction is studied by using an improved least squares support vector machine (LSSVM) regression based on chaotic mutation evolutionary programming (CMEP) approach for parameter optimization. We analyze how the prediction error varies with different parameters (σ, γ) in LS-SVM. In order to select appropriate parameters for the prediction model, we employ CMEP algorithm. Finally, Nasdaq stock data are predicted by using this LS-SVM regression based on CMEP, and satisfactory results are obtained. 展开更多
关键词 nonlinear time series prediction least squares support vector machine chaotic mutation evolu tionary programming
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Discussion About Nonlinear Time Series Prediction Using Least Squares Support Vector Machine 被引量:3
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作者 XURui-Rui BIANGuo-Xin GAOChen-Feng CHENTian-Lun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第6期1056-1060,共5页
The least squares support vector machine (LS-SVM) is used to study the nonlinear time series prediction. First, the parameter gamma and multi-step prediction capabilities of the LS-SVM network are discussed. Then we e... The least squares support vector machine (LS-SVM) is used to study the nonlinear time series prediction. First, the parameter gamma and multi-step prediction capabilities of the LS-SVM network are discussed. Then we employ clustering method in the model to prune the number of the support values.. The learning rate and the capabilities of filtering noise for LS-SVM are all greatly improved. 展开更多
关键词 least squares support vector machine nonlinear time series PREDICTION CLUSTERING
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A Trusted Measurement Scheme Suitable for the Clients in the Trusted Network 被引量:3
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作者 GONG Bei ZHANG Jianbiao +1 位作者 YE Xiaolie SHEN Changxiang 《China Communications》 SCIE CSCD 2014年第4期143-153,共11页
The trusted network connection is a hot spot in trusted computing field and the trust measurement and access control technology are used to deal with network security threats in trusted network.But the trusted network... The trusted network connection is a hot spot in trusted computing field and the trust measurement and access control technology are used to deal with network security threats in trusted network.But the trusted network connection lacks fine-grained states and real-time measurement support for the client and the authentication mechanism is difficult to apply in the trusted network connection,it is easy to cause the loss of identity privacy.In order to solve the abovedescribed problems,this paper presents a trust measurement scheme suitable for clients in the trusted network,the scheme integrates the following attributes such as authentication mechanism,state measurement,and real-time state measurement and so on,and based on the authentication mechanism and the initial state measurement,the scheme uses the realtime state measurement as the core method to complete the trust measurement for the client.This scheme presented in this paper supports both static and dynamic measurements.Overall,the characteristics of this scheme such as fine granularity,dynamic,real-time state measurement make it possible to make more fine-grained security policy and therefore it overcomes inadequacies existing in the current trusted network connection. 展开更多
关键词 trusted computing trusted network AUTHENTICATION state measurement real-time measurement
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Managing High Volume Data for Network Attack Detection Using Real-Time Flow Filtering
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作者 Abhrajit Ghosh Yitzchak M. Gottlieb +5 位作者 Aditya Naidu Akshay Vashist Alexander Poylisher Ayumu Kubota Yukiko Sawaya Akira Yamada 《China Communications》 SCIE CSCD 2013年第3期56-66,共11页
In this paper, we present Real-Time Flow Filter (RTFF) -a system that adopts a middle ground between coarse-grained volume anomaly detection and deep packet inspection. RTFF was designed with the goal of scaling to hi... In this paper, we present Real-Time Flow Filter (RTFF) -a system that adopts a middle ground between coarse-grained volume anomaly detection and deep packet inspection. RTFF was designed with the goal of scaling to high volume data feeds that are common in large Tier-1 ISP networks and providing rich, timely information on observed attacks. It is a software solution that is designed to run on off-the-shelf hardware platforms and incorporates a scalable data processing architecture along with lightweight analysis algorithms that make it suitable for deployment in large networks. RTFF also makes use of state of the art machine learning algorithms to construct attack models that can be used to detect as well as predict attacks. 展开更多
关键词 network security intrusion detection SCALING
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Rankings of Universities and Power in the Digital Age
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作者 Mario Alberto Velazquez Garcia Lilian lvetthe Salado Rodriguez 《Sociology Study》 2015年第4期269-281,共13页
This paper will discuss one topic in the current debate on higher education: How power is exercised between universities? How do colleges determine what the best college is? What are the differences in the excersis... This paper will discuss one topic in the current debate on higher education: How power is exercised between universities? How do colleges determine what the best college is? What are the differences in the excersise of power in the digital age? The authors analyze one of the mechanisms of relationship and contact between different universities: the rankings. They will discuss the practices that allow certain values and organizations they are becoming central nodes between universities and the influences of the information and communication technologies in the measurement mechanisms. The authors seek to show the rankings serve as mechanisms to exercise power among universities. These measurements become a tool and justification in competition between universities for resources such as funding, prestige, and student demand. The analysis is based on the University of Mexico, the authors use the ranking of the best universities in Latin America and the best universities in Mexico. 展开更多
关键词 TECHNOLOGY POWER UNIVERSITY RANKING Mexico
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Definition of Stationarity Based on Monitoring the Uncertainty at Real Measurement Conditions
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作者 Alois Heiss Woelfel Engineering Group 《Journal of Mechanics Engineering and Automation》 2018年第2期71-81,共11页
In the statistical standard literature the stationarity of a time dependent process generally is defined by the invariance in time of the distribution of the variable, like a SPL (sound pressure level) fluctuating i... In the statistical standard literature the stationarity of a time dependent process generally is defined by the invariance in time of the distribution of the variable, like a SPL (sound pressure level) fluctuating in time. However in reality there cannot exist constant distribution, respectively characteristics, in time in the strict mathematical sense because the time intervals of observation only can be finite due to practical reasons. Hence on every distribution and characteristics based on it a certain, but evaluable uncertainty is imposed. For monitoring these uncertainties the online-measurement technique, i.e. primarily appropriate software, is already available, also for customers. According to this state of the art the following expanded definition of the stationarity is proposed: Stationarity during a quality controlled measurement process becomes established, when the upper confidence limit of the interesting specific characteristic has no positive slope in time and correspondingly the lower confidence limit of the specific characteristic no negative slope and, as a third, a common condition, the interesting specific characteristic has adjusted itself to a constant position in time. From this a systematic criteria scheme is established and in examples applied on different in- and outdoor situations of sound impact. 展开更多
关键词 Stochastic processes stationarity UNCERTAINTY criteria.
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Measurement of Emissions from Passenger-Picking-up Vehicles at Airport Terminals
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作者 Fengxiang Qiao Larry Hill +1 位作者 Xiaobing Wang Lei Yu 《Journal of Environmental Science and Engineering(A)》 2016年第2期65-70,共6页
Rather than parking at nearby hourly parking lots, many passenger-picking-up vehicles prefer to idle at terminals and/or drive cycling around terminal facilities. As a result, extra vehicle emissions may be produced i... Rather than parking at nearby hourly parking lots, many passenger-picking-up vehicles prefer to idle at terminals and/or drive cycling around terminal facilities. As a result, extra vehicle emissions may be produced in an airport area. Even though there are limited studies on such emissions at airports, these estimations were normally based on the date emission models, which might cause bias in emission estimations. This paper proposes an approach to employ the floating car method and Global Positioning System (GPS) to record speeds and acceleration rates of idling and cycling vehicles at airport terminals. The tests were conducted under different time periods and traffic demands with different waiting time. The speeds and acceleration rates are synthesized to yield Vehicle Specific Power's (VSP) and Operational Mode (OM) distributions. Utilizing the Environmental Protection Agency (EPA) emission estimation model Motor Vehicle Emission Simulator (MOVES), pollutants and green house gas emission indexes (e.g. NOx, CO, CO2 and HC) and fuel consumptions can be easily estimated. As an illustration of the proposed approach, the research team collected GPS data at a terminal in Houston William Hobby Airport (HOU), and calculated the VSP distributions and OM distributions. Emissions of passenger-picking-up vehicles around these congested airport terminals. 展开更多
关键词 Vehicle emissions passenger-picking-up vehicle terminals AIRPORT vehicle specific power operational modedistribution.
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教会学生调节运动负荷的本领 被引量:2
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作者 刘家义 石云 《田径》 2017年第1期16-17,共2页
所谓运动负荷,是指人在练习时所承受的生理负荷。运动负荷包括运动量和运动强度两个方面。合理地安排和调节体育课运动负荷是对体育教师教学的一项基本要求,也是评价体育教学和体育活动锻炼效果的一项重要指标。学生掌握了调节运动负荷... 所谓运动负荷,是指人在练习时所承受的生理负荷。运动负荷包括运动量和运动强度两个方面。合理地安排和调节体育课运动负荷是对体育教师教学的一项基本要求,也是评价体育教学和体育活动锻炼效果的一项重要指标。学生掌握了调节运动负荷的本领,学会了科学锻炼身体的方法,克服了盲目性,提高了自觉性。对增强学生体质,掌握和提高运动技术、技能,提高运动成绩,防止伤害事故,都具有重要意义。 展开更多
关键词 运动负荷 体育教学 脉搏 测量时机 平均数
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A non-contact real-time measurement of lamp dimension based on machine vision 被引量:5
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作者 宋丽梅 王朋强 +4 位作者 常玉兰 李晓捷 习江涛 郭庆华 李秉男 《Optoelectronics Letters》 EI 2015年第2期145-148,共4页
In order to realize the online measurement of lamp dimension,the bulb image dimension measurement based on vision(BIDMV)is proposed.The image of lamp is obtained by camera.After image processing,such as Otsu algorithm... In order to realize the online measurement of lamp dimension,the bulb image dimension measurement based on vision(BIDMV)is proposed.The image of lamp is obtained by camera.After image processing,such as Otsu algorithm,median filter,ellipse fitting and envelope rectangle fitting,the dimension of lamp can be calculated.Based on this method,a non-contact real-time measurement system of the lamp’s dimension is developed.The precision of the proposed method is 0.07 mm,and it can satisfy the tolerance of the National Standard GB15766.1-2008.The experiment results show that the proposed method has a faster measuring speed and a higher precision compared with other measurement methods. 展开更多
关键词 Image processing Median filters Time measurement
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A new quantitative structure-retention relationship model for predicting chromatographic retention time of oligonucleotides 被引量:2
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作者 ZHAO Wei LIANG GuiZhao +1 位作者 CHEN YuZhen YANG Li 《Science China Chemistry》 SCIE EI CAS 2011年第7期1064-1071,共8页
An integrated approach is proposed to predict the chromatographic retention time of oligonucleotides based on quantitative structure-retention relationships (QSRR) models. First, the primary base sequences of oligon... An integrated approach is proposed to predict the chromatographic retention time of oligonucleotides based on quantitative structure-retention relationships (QSRR) models. First, the primary base sequences of oligonucleotides are translated into vectors based on scores of generalized base properties (SGBP), involving physicochemical, quantum chemical, topological, spatial structural properties, etc.; thereafter, the sequence data are transformed into a uniform matrix by auto cross covariance (ACC). ACC accounts for the interactions between bases at a certain distance apart in an oligonucleotide sequence; hence, this method adequately takes the neighboring effect into account. Then, a genetic algorithm is used to select the variables related to chromatographic retention behavior of oligonuclcotides. Finally, a support vector machine is used to develop QSRR models to predict chromatographic retention behavior. The whole dataset is divided into pairs of training sets and test sets with different proportions; as a result, it has been found that the QSRR models using more than 26 training samples have an appropriate external power, and can accurately represent the relationship between the features of sequences and structures, and the retention times. The results indicate that the SGBP-ACC approach is a useful structural representation method in QSRR of oligonucleotides due to its many advantages such as plentiful structural information, easy manipulation and high characterization competence. Moreover, the method can further be applied to predict chromatographic retention behavior of oligonucleotides. 展开更多
关键词 OLIGONUCLEOTIDE quantitative structure-retention relationship scores of generalized base properties auto cross covariance genetic algorithm support vector machine
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Measurements of the concentration of organic solutions by femtosecond time-resolved ERE-CARS
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作者 HE Ping WANG Ming +5 位作者 WANG HuiLi FAN RongWei CHEN DeYing YU Xin WANG JiaLing JIANG YuGang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第10期1808-1812,共5页
A variant of all-resonant CARS named electronic-resonant enhancement CARS (ERE-CARS) is applied to measure the methanol-water solution concentration at room temperature. The measurements are performed using the ERE-... A variant of all-resonant CARS named electronic-resonant enhancement CARS (ERE-CARS) is applied to measure the methanol-water solution concentration at room temperature. The measurements are performed using the ERE-CARS signal of the Raman vibrations near the C--H stretching modes (at 2835 and 2942 cm^-1) in methanol. By changing the timing (△t〉0) of the laser pulses of this non-degenerate four wave mixing technique, the concentration information based on the vibrational dynamics of the C--H bonds can be successfully detected as the frequency-spread dephasing rate duiing the first few hundred fs in the ERE-CARS signal with high sensitivity and accuracy. Femtosecond time-resolved ERE-CARS technique is applied to the concentration analysis of a mixture of the organic solution. This investigation indicates that femtosecond time-resolved ERE-CARS technique might be a powerful tool for real-time detection for solution concentration of different liquids. 展开更多
关键词 FEMTOSECOND ERE-CARS time-resolved spectroscopy CONCENTRATION
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