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Prediction of Lubricant Physicochemical Properties Based on Gaussian Copula Data Expansion
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作者 Feng Xin Yang Rui +1 位作者 Xie Peiyuan Xia Yanqiu 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第1期161-174,共14页
The composition of base oils affects the performance of lubricants made from them.This paper proposes a hybrid model based on gradient-boosted decision tree(GBDT)to analyze the effect of different ratios of KN4010,PAO... The composition of base oils affects the performance of lubricants made from them.This paper proposes a hybrid model based on gradient-boosted decision tree(GBDT)to analyze the effect of different ratios of KN4010,PAO40,and PriEco3000 component in a composite base oil system on the performance of lubricants.The study was conducted under small laboratory sample conditions,and a data expansion method using the Gaussian Copula function was proposed to improve the prediction ability of the hybrid model.The study also compared four optimization algorithms,sticky mushroom algorithm(SMA),genetic algorithm(GA),whale optimization algorithm(WOA),and seagull optimization algorithm(SOA),to predict the kinematic viscosity at 40℃,kinematic viscosity at 100℃,viscosity index,and oxidation induction time performance of the lubricant.The results showed that the Gaussian Copula function data expansion method improved the prediction ability of the hybrid model in the case of small samples.The SOA-GBDT hybrid model had the fastest convergence speed for the samples and the best prediction effect,with determination coefficients(R^(2))for the four indicators of lubricants reaching 0.98,0.99,0.96 and 0.96,respectively.Thus,this model can significantly reduce the model’s prediction error and has good prediction ability. 展开更多
关键词 base oil data augmentation machine learning performance prediction seagull algorithm
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An Exploration of Building a Thematic Sub-database within the Framework of DDE:A New Detrital Zircon U-Pb Dating Database
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作者 LI Chao LAI Wen +3 位作者 HU Xiumian XU Yajun YANG Jianghai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第S01期37-39,共3页
Within the framework of the Deep-time Digital Earth(DDE)project,thematic databases driven by scientific issues will have strong scientific vitality.In the field of sedimentology,thematic databases based on the current... Within the framework of the Deep-time Digital Earth(DDE)project,thematic databases driven by scientific issues will have strong scientific vitality.In the field of sedimentology,thematic databases based on the current unified sedimentary knowledge tree established by the Sedimentary Data Group(Fig.1),can solve specific scientific problems effectively and improve the scope and utility of the DDE platform significantly. 展开更多
关键词 DDE platform thematic database SEDIMENTARY knowledge TREE SEDIMENTARY data Group
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Blockchain-Based Cognitive Computing Model for Data Security on a Cloud Platform 被引量:1
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作者 Xiangmin Guo Guangjun Liang +1 位作者 Jiayin Liu Xianyi Chen 《Computers, Materials & Continua》 SCIE EI 2023年第12期3305-3323,共19页
Cloud storage is widely used by large companies to store vast amounts of data and files,offering flexibility,financial savings,and security.However,information shoplifting poses significant threats,potentially leading... Cloud storage is widely used by large companies to store vast amounts of data and files,offering flexibility,financial savings,and security.However,information shoplifting poses significant threats,potentially leading to poor performance and privacy breaches.Blockchain-based cognitive computing can help protect and maintain information security and privacy in cloud platforms,ensuring businesses can focus on business development.To ensure data security in cloud platforms,this research proposed a blockchain-based Hybridized Data Driven Cognitive Computing(HD2C)model.However,the proposed HD2C framework addresses breaches of the privacy information of mixed participants of the Internet of Things(IoT)in the cloud.HD2C is developed by combining Federated Learning(FL)with a Blockchain consensus algorithm to connect smart contracts with Proof of Authority.The“Data Island”problem can be solved by FL’s emphasis on privacy and lightning-fast processing,while Blockchain provides a decentralized incentive structure that is impervious to poisoning.FL with Blockchain allows quick consensus through smart member selection and verification.The HD2C paradigm significantly improves the computational processing efficiency of intelligent manufacturing.Extensive analysis results derived from IIoT datasets confirm HD2C superiority.When compared to other consensus algorithms,the Blockchain PoA’s foundational cost is significant.The accuracy and memory utilization evaluation results predict the total benefits of the system.In comparison to the values 0.004 and 0.04,the value of 0.4 achieves good accuracy.According to the experiment results,the number of transactions per second has minimal impact on memory requirements.The findings of this study resulted in the development of a brand-new IIoT framework based on blockchain technology. 展开更多
关键词 Blockchain Internet of Things(IoT) blockchain based cognitive computing Hybridized data Driven Cognitive Computing(HD2C) Federated Learning(FL) Proof of Authority(PoA)
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Creating Bengali Freebase Using Wikidata
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作者 Rukaiya Habib Mahmuda Ferdous Md Musfique Anwar 《Journal of Computer and Communications》 2023年第5期151-160,共10页
Freebase is a large collaborative knowledge base and database of general, structured information for public use. Its structured data had been harvested from many sources, including individual, user-submitted wiki cont... Freebase is a large collaborative knowledge base and database of general, structured information for public use. Its structured data had been harvested from many sources, including individual, user-submitted wiki contributions. Its aim is to create a global resource so that people (and machines) can access common information more effectively which is mostly available in English. In this research work, we have tried to build the technique of creating the Freebase for Bengali language. Today the number of Bengali articles on the internet is growing day by day. So it has become a necessary to have a structured data store in Bengali. It consists of different types of concepts (topics) and relationships between those topics. These include different types of areas like popular culture (e.g. films, music, books, sports, television), location information (restaurants, geolocations, businesses), scholarly information (linguistics, biology, astronomy), birth place of (poets, politicians, actor, actress) and general knowledge (Wikipedia). It will be much more helpful for relation extraction or any kind of Natural Language Processing (NLP) works on Bengali language. In this work, we identified the technique of creating the Bengali Freebase and made a collection of Bengali data. We applied SPARQL query language to extract information from natural language (Bengali) documents such as Wikidata which is typically in RDF (Resource Description Format) triple format. 展开更多
关键词 KNOWLEDGE-base Structured data NLP RDF
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原料性质大幅变化情况下催化重整Delta-Base数据的生成方法
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作者 宋雨雨 吕文进 +2 位作者 崔晨 宋建 周祥 《石油炼制与化工》 CAS CSCD 北大核心 2024年第8期157-163,共7页
针对催化重整原料性质变化幅度较大的情况,提出采用变步长计算结合分子水平机理模型生成装置Delta-Base数据的方法。该方法通过计算原料性质扰动时产品质量分数变化量绝对值随原料性质变化量绝对值的变化率;并将该变化率的值域分成若干... 针对催化重整原料性质变化幅度较大的情况,提出采用变步长计算结合分子水平机理模型生成装置Delta-Base数据的方法。该方法通过计算原料性质扰动时产品质量分数变化量绝对值随原料性质变化量绝对值的变化率;并将该变化率的值域分成若干等份,根据每次计算得到变化率值域的范围不同,选择下一步计算时的变量扰动步长;继而在计算过程中取每次变量扰动的中点值产品质量分数进行验证,从而在提高计算效率的同时保证了计算结果的准确性。结果表明:利用该方法计算得到的各产品质量分数相对误差较小,基本不超过2.5%;对计算数据拟合可得到不同产品质量分数数据拟合方程,通过拟合方程可生成芳烃潜含量变化三阶段Delta-Base数据;比较原料芳烃潜含量(w)为42%时的产品预测结果,发现Delta-Base数据预测值和拟合方程计算值的平均偏差均为0.16%,说明该方法具有很好的准确性,利用分子水平机理模型生成的Delta-Base数据更能反映真实的分子反应历程。 展开更多
关键词 催化重整 分子水平模型 线性规划 Delta-base数据
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Use of Linear Spectral Mixture Model to Estimate Rice Planted Area Based on MODIS Data 被引量:2
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作者 WANG Lei Satoshi UCHID 《Rice science》 SCIE 2008年第2期131-136,共6页
MODIS (Moderate Resolution Imaging Spectroradiometer) is a key instrument aboard the Terra (EOS AM) and Aqua (EOS PM) satellites. Linear spectral mixture models are applied to MOIDS data for the sub-pixel classi... MODIS (Moderate Resolution Imaging Spectroradiometer) is a key instrument aboard the Terra (EOS AM) and Aqua (EOS PM) satellites. Linear spectral mixture models are applied to MOIDS data for the sub-pixel classification of land covers. Shaoxing county of Zhejiang Province in China was chosen to be the study site and early rice was selected as the study crop. The derived proportions of land covers from MODIS pixel using linear spectral mixture models were compared with unsupervised classification derived from TM data acquired on the same day, which implies that MODIS data could be used as satellite data source for rice cultivation area estimation, possibly rice growth monitoring and yield forecasting on the regional scale. 展开更多
关键词 RICE planted area Moderate Resolution Imaging Spectroradiometer thematic Mapper data mixed pixel linear spectral mixture model
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“Deep-time Digital Basin” Based on Big Data and Artificial Intelligence 被引量:2
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作者 FENG Zhiqing LIAN Peiqing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第S01期14-16,共3页
1 Introduction Information technology has been playing an ever-increasing role in geoscience.Sphisicated database platforms are essential for geological data storage,analysis and exchange of Big Data(Feblowitz,2013;Zh... 1 Introduction Information technology has been playing an ever-increasing role in geoscience.Sphisicated database platforms are essential for geological data storage,analysis and exchange of Big Data(Feblowitz,2013;Zhang et al.,2016;Teng et al.,2016;Tian and Li,2018).The United States has built an information-sharing platform for state-owned scientific data as a national strategy. 展开更多
关键词 deep-time DIGITAL earth(DDE) deep-time DIGITAL basin(DDB) BIG data artificial intelligent knowledge base
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Data Mining and Neural Network Techniques in Case Based System 被引量:2
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作者 Ni Zhi wei 1,2 , Cai Qing sheng 1, Li Long shu 2 1.Department of Computer Science, University of Science and Technology of China,Hefei 230027,China 2.The Key Laboratory of Intelligent Computing and Signal Processing ,Ministry of Education 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期601-605,共5页
This paper first puts forward a case based system framework based on data mining techniques. Then the paper examines the possibility of using neural networks as a method of retrieval in such a case based system. In ... This paper first puts forward a case based system framework based on data mining techniques. Then the paper examines the possibility of using neural networks as a method of retrieval in such a case based system. In this system we propose data mining algorithms to discover case knowledge and other algorithms. 展开更多
关键词 data mining neural network case based reasoning retrieval algorithm
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Fast Web - Based Data Transmission 被引量:2
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作者 Wei Zukuan Department of Computer Science & Engineering, Inha University, Inchon 402 751, Korea Kim Jaehong Department of Computer Science, Youngdong University, Youngdong, Korea Bae Haeyoung Department of Computer Science & Engineering, Inha Uni 《Journal of China University of Geosciences》 SCIE CSCD 2001年第2期165-176,共12页
Since web based GIS processes large size spatial geographic information on internet, we should try to improve the efficiency of spatial data query processing and transmission. This paper presents two efficient metho... Since web based GIS processes large size spatial geographic information on internet, we should try to improve the efficiency of spatial data query processing and transmission. This paper presents two efficient methods for this purpose: division transmission and progressive transmission methods. In division transmission method, a map can be divided into several parts, called “tiles”, and only tiles can be transmitted at the request of a client. In progressive transmission method, a map can be split into several phase views based on the significance of vertices, and a server produces a target object and then transmits it progressively when this spatial object is requested from a client. In order to achieve these methods, the algorithms, “tile division”, “priority order estimation” and the strategies for data transmission are proposed in this paper, respectively. Compared with such traditional methods as “map total transmission” and “layer transmission”, the web based GIS data transmission, proposed in this paper, is advantageous in the increase of the data transmission efficiency by a great margin. 展开更多
关键词 spatial data transmission spatial query processing web based GIS geographic information system spatial database.
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A Path-Based Approach for Data Aggregation in Grid-Based Wireless Sensor Networks 被引量:1
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作者 Neng-Chung Wang Yung-Kuei Chiang Chih-Hung Hsieh 《Journal of Electronic Science and Technology》 CAS 2014年第3期313-317,共5页
Sensor nodes in a wireless sensor network (WSN) are typically powered by batteries, thus the energy is constrained. It is our design goal to efficiently utilize the energy of each sensor node to extend its lifetime,... Sensor nodes in a wireless sensor network (WSN) are typically powered by batteries, thus the energy is constrained. It is our design goal to efficiently utilize the energy of each sensor node to extend its lifetime, so as to prolong the lifetime of the whole WSN. In this paper, we propose a path-based data aggregation scheme (PBDAS) for grid-based wireless sensor networks. In order to extend the lifetime of a WSN, we construct a grid infrastructure by partitioning the whole sensor field into a grid of cells. Each cell has a head responsible for aggregating its own data with the data sensed by the others in the same cell and then transmitting out. In order to efficiently and rapidly transmit the data to the base station (BS), we link each cell head to form a chain. Each cell head on the chain takes turn becoming the chain leader responsible for transmitting data to the BS. Aggregated data moves from head to head along the chain, and finally the chain leader transmits to the BS. In PBDAS, only the cell heads need to transmit data toward the BS. Therefore, the data transmissions to the BS substantially decrease. Besides, the cell heads and chain leader are designated in turn according to the energy level so that the energy depletion of nodes is evenly distributed. Simulation results show that the proposed PBDAS extends the lifetime of sensor nodes, so as to make the lifetime of the whole network longer. 展开更多
关键词 base station cell head data aggregation grid-based wireless sensor networks
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The 8×10 GHz Receiver Optical Subassembly Based on Silica Hybrid Integration Technology for Data Center Interconnection 被引量:3
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作者 Chao-Yi Li Jun-Ming An +8 位作者 Jiu-Qi Wang Liang-Liang Wang Jia-Shun Zhang Jian-Guang Li Yuan-Da Wu Yue Wang Xiao-Jie Yin Yong Li Fei Zhong 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第10期39-43,共5页
An 8×10 GHz receiver optical sub-assembly (ROSA) consisting of an 8-channel arrayed waveguide grating (AWG) and an 8-channel PIN photodetector (PD) array is designed and fabricated based on silica hybrid in... An 8×10 GHz receiver optical sub-assembly (ROSA) consisting of an 8-channel arrayed waveguide grating (AWG) and an 8-channel PIN photodetector (PD) array is designed and fabricated based on silica hybrid integration technology. Multimode output waveguides in the silica AWG with 2% refractive index difference are used to obtain fiat-top spectra. The output waveguide facet is polished to 45° bevel to change the light propagation direction into the mesa-type PIN PD, which simplifies the packaging process. The experimentM results show that the single channel I dB bandwidth of AWG ranges from 2.12nm to 3.06nm, the ROSA responsivity ranges from 0.097 A/W to 0.158A/W, and the 3dB bandwidth is up to 11 GHz. It is promising to be applied in the eight-lane WDM transmission system in data center interconnection. 展开更多
关键词 AWG GHz Receiver Optical Subassembly based on Silica Hybrid Integration Technology for data Center Interconnection The 8 PD
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Proposed Caching Scheme for Optimizing Trade-off between Freshness and Energy Consumption in Name Data Networking Based IoT 被引量:1
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作者 Rahul Shrimali Hemal Shah Riya Chauhan 《Advances in Internet of Things》 2017年第2期11-24,共14页
Over the last few years, the Internet of Things (IoT) has become an omnipresent term. The IoT expands the existing common concepts, anytime and anyplace to the connectivity for anything. The proliferation in IoT offer... Over the last few years, the Internet of Things (IoT) has become an omnipresent term. The IoT expands the existing common concepts, anytime and anyplace to the connectivity for anything. The proliferation in IoT offers opportunities but may also bear risks. A hitherto neglected aspect is the possible increase in power consumption as smart devices in IoT applications are expected to be reachable by other devices at all times. This implies that the device is consuming electrical energy even when it is not in use for its primary function. Many researchers’ communities have started addressing storage ability like cache memory of smart devices using the concept called—Named Data Networking (NDN) to achieve better energy efficient communication model. In NDN, memory or buffer overflow is the common challenge especially when internal memory of node exceeds its limit and data with highest degree of freshness may not be accommodated and entire scenarios behaves like a traditional network. In such case, Data Caching is not performed by intermediate nodes to guarantee highest degree of freshness. On the periodical updates sent from data producers, it is exceedingly demanded that data consumers must get up to date information at cost of lease energy. Consequently, there is challenge in maintaining tradeoff between freshness energy consumption during Publisher-Subscriber interaction. In our work, we proposed the architecture to overcome cache strategy issue by Smart Caching Algorithm for improvement in memory management and data freshness. The smart caching strategy updates the data at precise interval by keeping garbage data into consideration. It is also observed from experiment that data redundancy can be easily obtained by ignoring/dropping data packets for the information which is not of interest by other participating nodes in network, ultimately leading to optimizing tradeoff between freshness and energy required. 展开更多
关键词 Internet of Things (IoT) Named data NETWORKING Smart CACHING Table Pending INTEREST Forwarding INFORMATION base CONTENT Store CONTENT Centric NETWORKING INFORMATION Centric NETWORKING data & INTEREST Packets SCTSmart CACHING
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Optimal Tracking Control for a Class of Unknown Discrete-time Systems with Actuator Saturation via Data-based ADP Algorithm 被引量:4
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作者 SONG Rui-Zhuo XIAO Wen-Dong SUN Chang-Yin 《自动化学报》 EI CSCD 北大核心 2013年第9期1413-1420,共8页
为有致动器浸透和未知动力学的分离时间的系统的一个班的一个新奇最佳的追踪控制方法在这份报纸被建议。计划基于反复的适应动态编程(自动数据处理) 算法。以便实现控制计划,一个 data-based 标识符首先为未知系统动力学被构造。由介绍... 为有致动器浸透和未知动力学的分离时间的系统的一个班的一个新奇最佳的追踪控制方法在这份报纸被建议。计划基于反复的适应动态编程(自动数据处理) 算法。以便实现控制计划,一个 data-based 标识符首先为未知系统动力学被构造。由介绍 M 网络,稳定的控制的明确的公式被完成。以便消除致动器浸透的效果, nonquadratic 表演功能被介绍,然后一个反复的自动数据处理算法被建立与集中分析完成最佳的追踪控制解决方案。为实现最佳的控制方法,神经网络被用来建立 data-based 标识符,计算性能索引功能,近似最佳的控制政策并且分别地解决稳定的控制。模拟例子被提供验证介绍最佳的追踪的控制计划的有效性。 展开更多
关键词 最优跟踪控制 离散时间系统 饱和执行器 DP算法 控制方案 神经网络 性能指标 系统动力学
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Percentile-based Neighborhood Precipitation Verification and Its Application to a Landfalling Tropical Storm Case with Radar Data Assimilation 被引量:3
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作者 ZHU Kefeng YANG Yi Ming XUE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第11期1449-1459,共11页
The traditional threat score based on fixed thresholds for precipitation verification is sensitive to intensity forecast bias. In this study, the neighborhood precipitation threat score is modified by defining the thr... The traditional threat score based on fixed thresholds for precipitation verification is sensitive to intensity forecast bias. In this study, the neighborhood precipitation threat score is modified by defining the thresholds in terms of the percentiles of overall precipitation instead of fixed threshold values. The impact of intensity forecast bias on the calculated threat score is reduced. The method is tested with the forecasts of a tropical storm that re-intensified after making landfall and caused heavy flooding. The forecasts are produced with and without radar data assimilation. The forecast with assimilation of both radial velocity and reflectivity produce precipitation patterns that better match observations but have large positive intensity bias. When using fixed thresholds, the neighborhood threat scores fail to yield high scores for forecasts that have good pattern match with observations, due to large intensity bias. In contrast, the percentile-based neighborhood method yields the highest score for the forecast with the best pattern match and the smallest position error. The percentile-based method also yields scores that are more consistent with object-based verifications, which are less sensitive to intensity bias, demonstrating the potential value of percentile-based verification. 展开更多
关键词 neighborhood precipitation threat score percentile-based verification radar data assimilation
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A Rule Management System for Knowledge Based Data Cleaning
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作者 Louardi BRADJI Mahmoud BOUFAIDA 《Intelligent Information Management》 2011年第6期230-239,共10页
In this paper, we propose a rule management system for data cleaning that is based on knowledge. This system combines features of both rule based systems and rule based data cleaning frameworks. The important advantag... In this paper, we propose a rule management system for data cleaning that is based on knowledge. This system combines features of both rule based systems and rule based data cleaning frameworks. The important advantages of our system are threefold. First, it aims at proposing a strong and unified rule form based on first order structure that permits the representation and management of all the types of rules and their quality via some characteristics. Second, it leads to increase the quality of rules which conditions the quality of data cleaning. Third, it uses an appropriate knowledge acquisition process, which is the weakest task in the current rule and knowledge based systems. As several research works have shown that data cleaning is rather driven by domain knowledge than by data, we have identified and analyzed the properties that distinguish knowledge and rules from data for better determining the most components of the proposed system. In order to illustrate our system, we also present a first experiment with a case study at health sector where we demonstrate how the system is useful for the improvement of data quality. The autonomy, extensibility and platform-independency of the proposed rule management system facilitate its incorporation in any system that is interested in data quality management. 展开更多
关键词 RULE data Quality data CLEANING KNOWLEDGE RULE Management SYSTEM RULE based SYSTEM Structure
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Analysis of Complex Correlated Interval-Censored HIV Data from Population Based Survey
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作者 Khangelani Zuma Goitseone Mafoko 《Open Journal of Statistics》 2015年第2期120-126,共7页
In studies of HIV, interval-censored data occur naturally. HIV infection time is not usually known exactly, only that it occurred before the survey, within some time interval or has not occurred at the time of the sur... In studies of HIV, interval-censored data occur naturally. HIV infection time is not usually known exactly, only that it occurred before the survey, within some time interval or has not occurred at the time of the survey. Infections are often clustered within geographical areas such as enumerator areas (EAs) and thus inducing unobserved frailty. In this paper we consider an approach for estimating parameters when infection time is unknown and assumed correlated within an EA where dependency is modeled as frailties assuming a normal distribution for frailties and a Weibull distribution for baseline hazards. The data was from a household based population survey that used a multi-stage stratified sample design to randomly select 23,275 interviewed individuals from 10,584 households of whom 15,851 interviewed individuals were further tested for HIV (crude prevalence = 9.1%). A further test conducted among those that tested HIV positive found 181 (12.5%) recently infected. Results show high degree of heterogeneity in HIV distribution between EAs translating to a modest correlation of 0.198. Intervention strategies should target geographical areas that contribute disproportionately to the epidemic of HIV. Further research needs to identify such hot spot areas and understand what factors make these areas prone to HIV. 展开更多
关键词 Analysis of COMPLEX CORRELATED Interval-Censored HIV data from Population based SURVEY
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Stroke Based Painterly Rendering with Mass Data through Auto Warping Generation
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作者 Taemin Lee Beomsik Kim +1 位作者 Sanghyun Seo Kyunghyun Yoon 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第3期1441-1457,共17页
Painting is done according to the artist’s style.The most representative of the style is the texture and shape of the brush stroke.Computer simulations allow the artist’s painting to be produced by taking this strok... Painting is done according to the artist’s style.The most representative of the style is the texture and shape of the brush stroke.Computer simulations allow the artist’s painting to be produced by taking this stroke and pasting it onto the image.This is called stroke-based rendering.The quality of the result depends on the number or quality of this stroke,since the stroke is taken to create the image.It is not easy to render using a large amount of information,as there is a limit to having a stroke scanned.In this work,we intend to produce rendering results using mass data that produces large amounts of strokes by expanding existing strokes through warping.Through this,we have produced results that have higher quality than conventional studies.Finally,we also compare the correlation between the amount of data and the results. 展开更多
关键词 Painterly rendering stroke based rendering image mass data stroke warping non-photorealistic rendering
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Construction of Free Amino Acids Composition Data Base for Food
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作者 Hinako Ito Hiroshi Ueno 《Journal of Chemistry and Chemical Engineering》 2014年第5期501-515,共15页
Significant amounts of free amino acids exist in commercially sold vegetables and fruits. Despite of the fact, only a little information is available about the free amino acid contents in foods. To utilize information... Significant amounts of free amino acids exist in commercially sold vegetables and fruits. Despite of the fact, only a little information is available about the free amino acid contents in foods. To utilize information of free amino acids in food, we have carried out the experiments to quantitate the free amino acids by derivatized with NBD-F (4-fluoro-7-nitrobenzofurazan) and analyzed on reversed-phase UHPLC (ultra-high pressure liquid chromatography) equipped with ultraviolet visible detector. Almost all of food extracts contained free amino acids including GABA (T-amino butyrate). Contents of free amino acids vary considerably depending upon vegetables and fruits. Principal free amino acids found in vegetables and fruits were asparagine, glutamine, arginine and GABA, which are involved in important metabolic pathways in human. About 140 species of vegetables and fruits were subjected for the data base. All of the plants and fruits we examined exhibit significant amount of free amino acids, those are clearly distinct from data bases obtained after acid hydrolysis treated food samples. Since glutamate and GABA act as excitatory and inhibitory neurotransmitters in CNS, respectively; free amino acids in vegetables and fruits that we eat daily, should be an important source for the cellular metabolic activities. 展开更多
关键词 Free amino acid GABA data base FOOD UHPLC.
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Semantic Analysis of Natural Language Queries for an Object Oriented Database
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作者 Bentamar Hemerelain Hafida Belbachir 《Journal of Software Engineering and Applications》 2010年第11期1047-1053,共7页
This paper presents the semantic analysis of queries written in natural language (French) and dedicated to the object oriented data bases. The studied queries include one or two nominal groups (NG) articulating around... This paper presents the semantic analysis of queries written in natural language (French) and dedicated to the object oriented data bases. The studied queries include one or two nominal groups (NG) articulating around a verb. A NG consists of one or several keywords (application dependent noun or value). Simple semantic filters are defined for identifying these keywords which can be of semantic value: class, simple attribute, composed attribute, key value or not key value. Coherence rules and coherence constraints are introduced, to check the validity of the co-occurrence of two consecutive nouns in complex NG. If a query is constituted of a single NG, no further analysis is required. Otherwise, if a query covers two valid NG, it is a subject of studying the semantic coherence of the verb and both NG which are attached to it. 展开更多
关键词 QUERY NOMINAL Group Natural LANGUAGE Object Oriented data base SEMANTIC Validation
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Global Statistical Study of Ionospheric Waves Based on COSMIC GPS Radio Occultation Data
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作者 Xuan-Yun Zeng Xiang-Hui Xue +4 位作者 Xin-An Yue Ming-Jiao Jia Bing-Kun Yu ian-Fei Wu Chao Yu 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第10期93-97,共5页
Extracting and parameterizing ionospheric waves globally and statistically is a longstanding problem. Based on the multichannel maximum entropy method(MMEM) used for studying ionospheric waves by previous work, we c... Extracting and parameterizing ionospheric waves globally and statistically is a longstanding problem. Based on the multichannel maximum entropy method(MMEM) used for studying ionospheric waves by previous work, we calculate the parameters of ionospheric waves by applying the MMEM to numerously temporally approximate and spatially close global-positioning-system radio occultation total electron content profile triples provided by the unique clustered satellites flight between years 2006 and 2007 right after the constellation observing system for meteorology, ionosphere, and climate(COSMIC) mission launch. The results show that the amplitude of ionospheric waves increases at the low and high latitudes(~0.15 TECU) and decreases in the mid-latitudes(~0.05 TECU). The vertical wavelength of the ionospheric waves increases in the mid-latitudes(e.g., ~50 km at altitudes of 200–250 km) and decreases at the low and high latitudes(e.g., ~35 km at altitudes of 200–250 km).The horizontal wavelength shows a similar result(e.g., ~1400 km in the mid-latitudes and ~800 km at the low and high latitudes). 展开更多
关键词 COSMIC Global Statistical Study of Ionospheric Waves based on COSMIC GPS Radio Occultation data GPS
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