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International Journal of Technology Management 2015年第7期 152-154页

作者： Ying Cao Northeast Petroleum University QinhuangdaoHebei066000 China

In this paper, we research the probability theory and matrix transformation based technique to manage the data for processing and analysis. Clustering analysis research has a long history, over the decades, the importance and the cross characteristics with other research direction to get the affirmation of the people. The probability theory and linear algebra act as the powerful tool for analyzing and mining data. The experimental result illustrates the effectiveness. In the near future, we plan to conduct more theoretical analysis on the topic.

关键词： probability model Matrix Transformation Data Analysis and Management.

A Feature Compensation Method Based probability model and Spectrum Difference

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A Feature Compensation Method Based Probability Model and Sp...

probability-based analytical model for predicting the post-earthquake residual deformation of SDOF systems

第一届建立和谐人机环境联合学术会议（HHME2005）

作者： Ma Zhifei Chenshuo Wang Bingxi PLA Information and Engineering University

The article introduces a new feature compensation method which will induct the relativity of the prediction of spectrum based probability model in detail. The method evaluates the parameters of the jo

关键词： speech recognition denoising probability model spectrum difference

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Earthquake Engineering and Engineering Vibration 2022年第2期21卷 341-358页

作者： Zhang Qin Gong Susu Gong Jinxin Zhang Guanhua Xi Guangheng College of Civil and Transportation Engineering Hohai UniversityNanjing 210098China Highway Maintenance Technology Research and Development Center of Liaoning Provincial Communication Planning&Design Insitute Co.Ltd. Shenyang 110111China Department of Civil Engineering Dalian University of TechnologyDalian 116014China

A probability-based analytical model for predicting the seismic residual deformation of bilinear single-degreeof-freedom(SDOF)systems with a kinematic/Takeda hysteretic model is proposed based on a statistical analysis of the nonlinear time history response,and the proposed model explicitly incorporates the influence of record-to-record *** addition,the influence of primary parameters such as the natural vibration period,relative yield force coefficient,stiffness ratio and peak ground acceleration(PGA)on the seismic residual/maximum deformation ratio(dR/dm)are *** results show that significant dispersion of the dR/dm ratio is observed for SDOF systems under different seismic ground motion records,and the dispersion degree is influenced by the model parameters and record-to-record *** statistical distribution of the dR/dm results of SDOF systems can be described by a lognormal ***,a case study for seismic residual deformation and reparability assessment of the bridge structure designed with a single pier is carried out to illustrate the detailed analytical procedure of the probability-based analytical model proposed in this study.

关键词： residual deformation probability model repairability assessment single-degree-of-freedom system nonlinear seismic response record-to-record variability

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On the Application of Mixed models of probability and Convex Set for Time-Variant Reliability Analysis

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Computer modeling in Engineering & Sciences 2024年第5期139卷 1981-1999页

作者： Fangyi Li Dachang Zhu Huimin Shi Center for Research on Leading Technology of Special Equipment School of Mechanical and Electric EngineeringGuangzhou UniversityGuangzhou510006China

In time-variant reliability problems,there are a lot of uncertain variables from different ***,it is important to consider these uncertainties in *** addition,time-variant reliability problems typically involve a complexmultilevel nested optimization problem,which can result in an enormous amount of *** this end,this paper studies the time-variant reliability evaluation of structures with stochastic and bounded uncertainties using a mixed probability and convex set *** this method,the stochastic process of a limit-state function with mixed uncertain parameters is first discretized and then converted into a timeindependent reliability ***,to solve the double nested optimization problem in hybrid reliability calculation,an efficient iterative scheme is designed in standard uncertainty space to determine the most probable point(MPP).The limit state function is linearized at these points,and an innovative random variable is defined to solve the equivalent static reliability analysis *** effectiveness of the proposed method is verified by two benchmark numerical examples and a practical engineering problem.

关键词： Mixed uncertainty probability model convex model time-variant reliability analysis

Global Optimization for Advertisement Selection in Sponsored Search

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Journal of Computer Science & Technology 2015年第2期30卷 295-310页

作者：崔卿白峰杉高斌刘铁岩 Department of Mathematical Sciences Tsinghua University Beijing 100084 China Microsoft Research Asia Beijing 100080 China

Advertisement （ad） selection plays an important role in sponsored search, since it is an upstream component and will heavily influence the effectiveness of the subsequent auction mechanism. However, most existing ad selection methods regard ad selection as a relatively independent module, and only consider the literal or semantic matching between queries and keywords during the ad selection process. In this paper, we argue that this approach is not globally optimal. Our proposal is to formulate ad selection as such an optimization problem that the selected ads can work together with downstream components （e.g., the auction mechanism） to achieve the maximization of user clicks, advertiser social welfare, and search engine revenue （we call the combination of these objective functions as the marketplace objective for ease of reference）. To this end, we 1） extract a bunch of features to represent each pair of query and keyword, and 2） train a machine learning model that maps the features to a binary variable indicating whether the keyword is selected or not, by maximizing the aforementioned marketplace objective. This formalization seems quite natural; however, it is technically difficult because the marketplace objective is non-convex, discontinuous, and indifferentiable regarding the model parameter due to the ranking and second-price rules in the auction mechanism. To tackle the challenge, we propose a probabilistic approximation of the marketplace objective, which is smooth and can be effectively optimized by conventional optimization techniques. We test the ad selection model learned with our proposed method using the sponsored search log from a commercial search engine. The experimental results show that our method can significantly outperform several ad selection algorithms on all the metrics under investigation.

关键词： advertisement selection sponsored search probability model

Probabilistic model of disc-cutter wear in TBM construction:A case study of Chaoer to Xiliao water conveyance tunnel in China

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Science China(Technological Sciences) 2023年第12期66卷 3534-3548页

作者： YANG WenKun CHEN ZuYu WU GenSheng XING Hai School of Civil Engineering Institute of Future Underground SpaceSoutheast UniversityNanjing 211189China Department of Geotechnical Engineering China Institute of Water Resources and Hydropower ResearchBeijing 100038China Sinohydro Bureau 6 Co. Ltd.Shenyang 110179China

Disc-cutters play a crucial role in the penetration process during construction using a tunnel boring machine(TBM).Their wear status has a significant impact on working efficiency and costs that accounts for a large part of the *** the wear pattern and characteristics of disc-cutters could provide a valuable guide for field maintenance and cutter replacement *** also provides insight into the wear mechanism of cutters at different positions for optimizing the disc-cutter arrangement *** this study,the cutter wears data of 34 disc-cutters over 643 days in the Chaoer River to Xiliao River water diversion tunnel was *** dataset contains 21862 manual readings measured from 1079 disc-cutters replaced in this *** raw data from the hard copy version was transformed into a digital twin database by eliminating abnormal data,filling in empty values,and performing linear *** has been found that the cutters can pass statistical testing for an exponential probability distribution function with respect to the wear rate(w).The regression ratios of R2are essentially greater than *** findings would help estimate the future service life of a currently working cutter,which means significant savings for the costly *** application of exponential distribution has the advantage of only one shape parameter,λ,whose reciprocal represents both the statistical mean and standard deviation of the wear *** is simple and practically amenable.A preliminary study was carried out to simulate the wear process between two neighboring cutters for drafting a replacement plan for disc-cutters by the Monte Carlo *** prediction results agreed reasonably well with the measured information.

关键词： tunnel boring machine disc-cutter wear wear rate probability model

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Development of predictive models for egg freshness and shelf-life under different storage temperatures

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Food Quality and Safety 2021年第4期5卷 344-350页

作者： Chunli Quan Qian Xi Xueping Shi Rongwei Han Qijing Du Fereidoun Forghani Chuanyun Xue Jiacheng Zhang Jun Wang College of Food Science and Engineering Qingdao Agricultural UniversityQingdaoChina College of Life Science Tarim UniversityAlarChina College of Animal Science and Technology Qingdao Agricultural UniversityQingdaoChina Shandong Engineering Technology Research Center of Food Quality and Safety Control QingdaoChina Molecular Epidemiology Inc.Lake Forest ParkWAUSA

The objective of the present study was to develop models for egg freshness and shelf-life predictions for the selected evaluation indicators including egg weight,Flaugh unit(HU),and albumen *** were carried out at different storage temperatures for a total period of 29-32 *** data were collected and fitted in to Arrhenius equation for egg freshness,while the HU data were applied to a probability model for shelf-life *** results showed that egg weight,albumen height,and HU decreased significantly,while albumen pH increased with the extension of storage *** higher the storage temperature,the faster the egg quality *** addition,the bias factor,accuracy factor,and the standard error of prediction were selected to verify the developed quality *** rescaled R-square statistic,the Hosmer-Lemeshow goodness-of-fit statistic,and the receiver operating characteristic curve were used to evaluate the goodness-of-fit of the developed probability model for the shelf-life of eggs,which indicated that the presented predictive models can be used to assess egg freshness and predict shelf-life during different storage temperatures.

关键词： Eggs predictive models probability model shelf-life freshness

Timely Data Delivery for Energy-Harvesting IoT Devices

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Chinese Journal of Electronics 2022年第2期31卷 322-336页

作者： LU Wenwei GONG Siliang ZHU Yihua School of Computer Science and Technology Zhejiang University of Technology College of Mathematics and Computer Science Zhejiang A&F University

The devices in the Internet of things(Io T) gain capability of sustainable operation when they harvest energy from ambient sources. Fluctuation in the harvested energy may cause the energy-harvesting IoT devices to suffer from frequent energy shortage, which may bring in intolerable packet delay or packet discarding. It is important to design a low-delay packet delivery scheme that adapts to variation in the harvested *** this paper, we present the timely data delivery(TDD)scheme for the IoT devices. Using Markov chain, we develop a probability model for the TDD scheme, which leads to the expected number of packets delivered in an operation cycle, the expected numbers of packets waiting in the data buffer in an operation cycle and an energy-harvesting cycle, and the expected packet delay. Additionally, we formulate the optimization problem that minimizes the packet delay in the TDD scheme, and the solution to the optimization problem yields the optimal parameters for the IoT devices to determine when to harvest energy and when to deliver data under the TDD *** simulation results show that the proposed TDD scheme outperforms the existing schemes in terms of packet delay.

关键词： operation cycle harvested energy probability model low-delay packet delivery scheme energy-harvesting cycle Internet of Things Markov processes probability expected packet delay Markov chain frequent energy shortage energy-harvesting IoT devices optimisation timely data delivery scheme intolerable packet delay packet discarding TDD scheme energy harvesting delays Internet of things telecommunication power management

Micro-blogs Entity Recognition Based on DSTCRF

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Chinese Journal of Electronics 2014年第1期23卷 147-150页

作者： WANG Jing LIU Zhijing ZHAO Hui Xidian University Xi'an Jiaotong University

We proposed a unified model for Chinese named entity recognition in micro-blogs. The models provide a simple statistical framework to incorporate a wide variety of linguistic knowledge and statistical models in a unified way. In our approach, KNN classifier is used to get suitable training data. An optimal algorithm to generate the hierarchically structured DSTCRF is executed to select the structure attributes of the named entity in micro-blogs knowledge. The experimental results showed that the accuracy rate was significantly improved.

关键词： Named entity Micro-blog probability model

Micromechanical Study on Moisture Induced Tensile Strength Reduction of GFRP

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Transactions of Nanjing University of Aeronautics and Astronautics 2022年第2期39卷 250-262页

作者： GAO Chaogan ZHOU Chuwei State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China

The main focus of this paper is to investigate the influence of hygrothermal aging on tensile strength of epoxy resin matrix ***,tests of water absorption and moisture induced tensile strength degradation of glass fiber reinforced polymer(GFRP)are *** show that the moisture absorption behavior of the GFRP follows the Fick’s law,and its tensile strength retention decreases notably in the early hygrothermal aging stage and then gradually approaches a ***,microscale longitudinal and transverse strength prediction models for unidirectional fiber reinforced composites are *** are moisture concentration dependent and reflect the inherent probability of failures of fiber and matrix(or fiber/matrix interface).The moisture diffusing analysis demostrates that the proposed models can predict degradation of tensile strength of epoxy resin matrix composites undergoing different hygrothermal *** proposed models are validated by the experiments of hygrothermal residual strength of the GFRP mentioned above.

关键词： composites hygrothermal aging residual strength micromechanics probability model

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