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Reconstruction of incomplete satellite SST data sets based on EOF method 被引量:2
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作者 DING Youzhuan WEI Zhihui +2 位作者 MAO Zhihua WANG Xiaofei PAN Delu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2009年第2期36-44,共9页
As for the satellite remote sensing data obtained by the visible and infrared bands myers,on, the clouds coverage in the sky over the ocean often results in missing data of inversion products on a large scale, and thi... As for the satellite remote sensing data obtained by the visible and infrared bands myers,on, the clouds coverage in the sky over the ocean often results in missing data of inversion products on a large scale, and thin clouds difficult to be detected would cause the data of the inversion products to be abnormal. Alvera et a1.(2005) proposed a method for the reconstruction of missing data based on an Empirical Orthogonal Functions (EOF) decomposition, but his method couldn't process these images presenting extreme cloud coverage(more than 95%), and required a long time for recon- struction. Besides, the abnormal data in the images had a great effect on the reconstruction result. Therefore, this paper tries to improve the study result. It has reconstructed missing data sets by twice applying EOF decomposition method. Firstly, the abnormity time has been detected by analyzing the temporal modes of EOF decomposition, and the abnormal data have been eliminated. Secondly, the data sets, excluding the abnormal data, are analyzed by using EOF decomposition, and then the temporal modes undergo a filtering process so as to enhance the ability of reconstruct- ing the images which are of no or just a little data, by using EOF. At last, this method has been applied to a large data set, i.e. 43 Sea Surface Temperature (SST) satellite images of the Changjiang River (Yangtze River) estuary and its adjacent areas, and the total reconstruction root mean square error (RMSE) is 0.82℃. And it has been proved that this improved EOF reconstruction method is robust for reconstructing satellite missing data and unreliable data. 展开更多
关键词 EOF SST Changjiang River estuary Missing data sets
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Evolution algorithm for water storage forecasting response to climate change with little data sets:the Wolonghu Wetland,China
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作者 尼庆伟 叶人珍 +1 位作者 杨凤林 雷坤 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第2期127-133,共7页
An attempt of applying a novel genetic programming(GP) technique,a new member of evolution algorithms,has been made to predict the water storage of Wolonghu wetland response to the climate change in northeastern part ... An attempt of applying a novel genetic programming(GP) technique,a new member of evolution algorithms,has been made to predict the water storage of Wolonghu wetland response to the climate change in northeastern part of China with little data set.Fourteen years(1993-2006) of annual water storage and climatic data set of the wetland were taken for model training and testing.The results of simulations and predictions illustrated a good fit between calculated water storage and observed values(MAPE=9.47,r=0.99).By comparison,a multilayer perceptron(MLP)(a popular artificial neural network model) method and a grey model(GM) with the same data set were applied for performances estimation.It was found that GP technique had better performances than the other two methods both in the simulation step and predicting phase and the results were analyzed and discussed.The case study confirmed that GP method is a promising way for wetland managers to make a quick estimation of fluctuations of water storage in some wetlands under condition of little data set. 展开更多
关键词 water storage little data set evolution algorism Wolonghu wetland
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Incidence and Survivability of Acute Lymphocytic Leukemia Patients in the United States: Analysis of SEER Data Set from 2000-2019
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作者 Ishan Ghosh Sudipto Mukherjee 《Journal of Cancer Therapy》 2024年第4期141-163,共23页
The main goal of this research is to assess the impact of race, age at diagnosis, sex, and phenotype on the incidence and survivability of acute lymphocytic leukemia (ALL) among patients in the United States. By takin... The main goal of this research is to assess the impact of race, age at diagnosis, sex, and phenotype on the incidence and survivability of acute lymphocytic leukemia (ALL) among patients in the United States. By taking these factors into account, the study aims to explore how existing cancer registry data can aid in the early detection and effective treatment of ALL in patients. Our hypothesis was that statistically significant correlations exist between race, age at which patients were diagnosed, sex, and phenotype of the ALL patients, and their rate of incidence and survivability data were evaluated using SEER*Stat statistical software from National Cancer Institute. Analysis of the incidence data revealed that a higher prevalence of ALL was among the Caucasian population. The majority of ALL cases (59%) occurred in patients aged between 0 to 19 years at the time of diagnosis, and 56% of the affected individuals were male. The B-cell phenotype was predominantly associated with ALL cases (73%). When analyzing survivability data, it was observed that the 5-year survival rates slightly exceeded the 10-year survival rates for the respective demographics. Survivability rates of African Americans patients were the lowest compared to Caucasian, Asian, Pacific Islanders, Alaskan Native, Native Americans and others. Survivability rates progressively decreased for older patients. Moreover, this study investigated the typical treatment methods applied to ALL patients, mainly comprising chemotherapy, with occasional supplementation of radiation therapy as required. The study demonstrated the considerable efficacy of chemotherapy in enhancing patients’ chances of survival, while those who remained untreated faced a less favorable prognosis from the disease. Although a significant amount of data and information exists, this study can help doctors in the future by diagnosing patients with certain characteristics. It will further assist the health care professionals in screening potential patients and early detection of cases. This could also save the lives of elderly patients who have a higher mortality rate from this disease. 展开更多
关键词 Acute Lymphocytic Leukemia SURVIVABILITY INCIDENCE DEMOGRAPHY SEER data Set
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Top-k probabilistic prevalent co-location mining in spatially uncertain data sets 被引量:5
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作者 Lizhen WANG Jun HAN +1 位作者 Hongmei CHEN Junli LU 《Frontiers of Computer Science》 SCIE EI CSCD 2016年第3期488-503,共16页
A co-location pattern is a set of spatial features whose instances frequently appear in a spatial neighborhood. This paper efficiently mines the top-k probabilistic prevalent co-locations over spatially uncertain data... A co-location pattern is a set of spatial features whose instances frequently appear in a spatial neighborhood. This paper efficiently mines the top-k probabilistic prevalent co-locations over spatially uncertain data sets and makes the following contributions: 1) the concept of the top-k prob- abilistic prevalent co-locations based on a possible world model is defined; 2) a framework for discovering the top- k probabilistic prevalent co-locations is set up; 3) a matrix method is proposed to improve the computation of the preva- lence probability of a top-k candidate, and two pruning rules of the matrix block are given to accelerate the search for ex- act solutions; 4) a polynomial matrix is developed to further speed up the top-k candidate refinement process; 5) an ap- proximate algorithm with compensation factor is introduced so that relatively large quantity of data can be processed quickly. The efficiency of our proposed algorithms as well as the accuracy of the approximation algorithms is evaluated with an extensive set of experiments using both synthetic and real uncertain data sets. 展开更多
关键词 spatial co-location mining top-k probabilistic prevalent co-location mining spatially uncertain data sets matrix methods
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Constructing Isosurfaces from 3D Data Sets Taking Account of Depth Sorting of Polyhedra
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作者 周勇 唐泽圣 《Journal of Computer Science & Technology》 SCIE EI CSCD 1994年第2期117-127,共11页
Creating and rendering intermediate geometric primitives is one of the approaches to visualize data sets in 3D space. Some algorithms have been developed to construct isosurface from uniformly distributed 3D data sets... Creating and rendering intermediate geometric primitives is one of the approaches to visualize data sets in 3D space. Some algorithms have been developed to construct isosurface from uniformly distributed 3D data sets. These algorithms assume that the function value varies linearly along edges of each cell. But to irregular 3D data sets, this assumption is inapplicable. Moreover, the depth sorting of cells is more complicated for irregular data sets, which is indispensable for generating isosurface images or semitransparent isosurface images, if Z-buffer method is not adopted.In this paper, isosurface models based on the assumption that the function value has nonlinear distribution within a tetrahedroll are proposed. The depth sorting algorithm and data structures are developed for the irregular data sets in which cells may be subdivided into tetrahedra. The implementation issues of this algorithm are discussed and experimental results are shown to illustrate potentials of this technique. 展开更多
关键词 ISOSURFACE 3D data sets depth sorting POLYHEDRA
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An Evaluation of the Reliability of Complex Systems Using Shadowed Sets and Fuzzy Lifetime Data 被引量:3
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作者 Olgierd Hryniewicz 《International Journal of Automation and computing》 EI 2006年第2期145-150,共6页
In this paper, we consider the problem of the evaluation of system reliability using statistical data obtained from reliability tests of its elements, in which the lifetimes of elements are described using an exponent... In this paper, we consider the problem of the evaluation of system reliability using statistical data obtained from reliability tests of its elements, in which the lifetimes of elements are described using an exponential distribution. We assume that this lifetime data may be reported imprecisely and that this lack of precision may be described using fuzzy sets. As the direct application of the fuzzy sets methodology leads in this case to very complicated and time consuming calculations, we propose simple approximations of fuzzy numbers using shadowed sets introduced by Pedrycz (1998). The proposed methodology may be simply extended to the case of general lifetime probability distributions. 展开更多
关键词 Estimation of reliability fuzzy reliability data shadowed sets.
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A dataset of scientific literature on floods,1990-2017
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作者 Zhang Hongyue Li Guoqing +2 位作者 Huang Mingrui Qing Xiuling Zhang Huarong 《中国科学数据(中英文网络版)》 CSCD 2018年第3期76-85,共10页
With an increasing number of scientific achievements published,it is particularly important to conduct literature-based knowledge discovery and data mining.Flood,as one of the most destructive natural disasters,has be... With an increasing number of scientific achievements published,it is particularly important to conduct literature-based knowledge discovery and data mining.Flood,as one of the most destructive natural disasters,has been the subject of numerous scientific publications.On January 1,2018,we conducted literature data collection and processing on flood research and categorized the retrieved paper records into Whole SCI Dataset(WS)and High-Citation SCI Dataset(HCS).These data sets can serve as basic data for bibliometric analysis to identify the status of global flood research during 1990-2017.Our study shows that while the Chinese Academy of Sciences was the most productive institution during this period,the United States was the most productive country.Besides,our keyword analysis reveals the potential popular issues and future trends of flood research. 展开更多
关键词 literature data sets FLOOD WS HCS
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Oil-gas reservoir in the Mesozoic strata in the Chaoshan depression,northern South China Sea:a new insight from long off set seismic data 被引量:1
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作者 Tao XING Guangjian ZHONG +2 位作者 Wenhuan ZHAN Zhongquan ZHAO Xi CHEN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第4期1377-1387,共11页
The Chaoshan depression,a Mesozoic basin in the Dongsha sea area,northern South China Sea,is characterized by well-preserved Mesozoic strata,being good conditions for oil-gas preservation,promising good prospects for ... The Chaoshan depression,a Mesozoic basin in the Dongsha sea area,northern South China Sea,is characterized by well-preserved Mesozoic strata,being good conditions for oil-gas preservation,promising good prospects for oil-gas exploration.However,breakthrough in oil-gas exploration in the Mesozoic strata has not been achieved due to less seismic surveys.New long-off set seismic data were processed that acquired with dense grid with single source and single cable.In addition,the data were processed with 3D imaging method and fi ner processing was performed to highlight the target strata.Combining the new imaging result and other geological information,we conducted integrated interpretation and proposed an exploratory well A-1-1 for potential hydrocarbon.The result provides a reliable basis for achieving breakthroughs in oil and gas exploration in the Mesozoic strata in the northern South China Sea. 展开更多
关键词 Chaoshan depression Mesozoic strata oil and gas exploration long off set seismic data integrated interpretation exploratory well
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A Middleware for Polyglot Persistence and Data Portability of Big Data PaaS Cloud Applications
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作者 Kiranbir Kaur Sandeep Sharma Karanjeet Singh Kahlon 《Computers, Materials & Continua》 SCIE EI 2020年第11期1625-1647,共23页
Vendor lock-in can occur at any layer of the cloud stack-Infrastructure,Platform,and Software-as-a-service.This paper covers the vendor lock-in issue at Platform as a Service(PaaS)level where applications can be creat... Vendor lock-in can occur at any layer of the cloud stack-Infrastructure,Platform,and Software-as-a-service.This paper covers the vendor lock-in issue at Platform as a Service(PaaS)level where applications can be created,deployed,and managed without worrying about the underlying infrastructure.These applications and their persisted data on one PaaS provider are not easy to port to another provider.To overcome this issue,we propose a middleware to abstract and make the database services as cloud-agnostic.The middleware supports several SQL and NoSQL data stores that can be hosted and ported among disparate PaaS providers.It facilitates the developers with data portability and data migration among relational and NoSQL-based cloud databases.NoSQL databases are fundamental to endure Big Data applications as they support the handling of an enormous volume of highly variable data while assuring fault tolerance,availability,and scalability.The implementation of the middleware depicts that using it alleviates the efforts of rewriting the application code while changing the backend database system.A working protocol of a migration tool has been developed using this middleware to facilitate the migration of the database(move existing data from a database on one cloud to a new database even on a different cloud).Although the middleware adds some overhead compared to the native code for the cloud services being used,the experimental evaluation on Twitter(a Big Data application)data set,proves this overhead is negligible. 展开更多
关键词 Cloud computing platform as a service MIDDLEWARE polyglot persistence SQL NOSQL data migration tool Twitter data set
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Robustness Evaluation of Remote-Sensing Image Feature Detectors with TH Priori-Information Data Set
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作者 Yiping Duan Xiaoming Tao +1 位作者 Xijia Liu Ning Ge 《China Communications》 SCIE CSCD 2020年第10期218-228,共11页
In this paper,we build a remote-sensing satellite imagery priori-information data set,and propose an approach to evaluate the robustness of remote-sensing image feature detectors.The building TH Priori-Information(TPI... In this paper,we build a remote-sensing satellite imagery priori-information data set,and propose an approach to evaluate the robustness of remote-sensing image feature detectors.The building TH Priori-Information(TPI)data set with 2297 remote sensing images serves as a standardized high-resolution data set for studies related to remote-sensing image features.The TPI contains 1)raw and calibrated remote-sensing images with high spatial and temporal resolutions(up to 2 m and 7 days,respectively),and 2)a built-in 3-D target area model that supports view position,view angle,lighting,shadowing,and other transformations.Based on TPI,we further present a quantized approach,including the feature recurrence rate,the feature match score,and the weighted feature robustness score,to evaluate the robustness of remote-sensing image feature detectors.The quantized approach gives general and objective assessments of the robustness of feature detectors under complex remote-sensing circumstances.Three remote-sensing image feature detectors,including scale-invariant feature transform(SIFT),speeded up robust features(SURF),and priori information based robust features(PIRF),are evaluated using the proposed approach on the TPI data set.Experimental results show that the robustness of PIRF outperforms others by over 6.2%. 展开更多
关键词 REMOTE-SENSING TH data set image feature robustness evaluation
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Hybrid Warehouse Model and Solutions for Climate Data Analysis
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作者 Hasan Hashim 《Journal of Computer and Communications》 2020年第10期75-98,共24页
Recently, due to the rapid growth increment of data sensors, a massive volume of data is generated from different sources. The way of administering such data in a sense storing, managing, analyzing, and extracting ins... Recently, due to the rapid growth increment of data sensors, a massive volume of data is generated from different sources. The way of administering such data in a sense storing, managing, analyzing, and extracting insightful information from the massive volume of data is a challenging task. Big data analytics is becoming a vital research area in domains such as climate data analysis which demands fast access to data. Nowadays, an open-source platform namely MapReduce which is a distributed computing framework is widely used in many domains of big data analysis. In our work, we have developed a conceptual framework of data modeling essentially useful for the implementation of a hybrid data warehouse model to store the features of National Climatic Data Center (NCDC) climate data. The hybrid data warehouse model for climate big data enables for the identification of weather patterns that would be applicable in agricultural and other similar climate change-related studies that will play a major role in recommending actions to be taken by domain experts and make contingency plans over extreme cases of weather variability. 展开更多
关键词 data Warehouse HADOOP NCDC data Set WEATHER
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ERA5再分析10m风速数据在“两洋一海”的适用性分析 被引量:3
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作者 陈君芝 施晓晖 温敏 《气象》 CSCD 北大核心 2023年第1期39-51,共13页
西太平洋-南海-东印度洋(以下简称“两洋一海”)地区对我国的天气气候、国家安全和社会经济有重要影响,但由于资料条件的限制,现有的海上高风速事件研究主要集中于近海,导致对“两洋一海”地区远洋高风速事件的时空分布、变化特征及其... 西太平洋-南海-东印度洋(以下简称“两洋一海”)地区对我国的天气气候、国家安全和社会经济有重要影响,但由于资料条件的限制,现有的海上高风速事件研究主要集中于近海,导致对“两洋一海”地区远洋高风速事件的时空分布、变化特征及其机理仍然不够了解,急需利用新的高分辨率资料进行深入的研究。目前欧州中期天气预报中心第五代全球大气再分析资料(ERA5)再分析近地面10 m风速数据与现场观测风速的比较研究还相对较少,因此本文将“两洋一海”地区的国际海洋大气综合数据集(ICOADS)锚定浮标观测资料与ERA5进行了对比分析。结果表明:ERA5再分析10 m风速数据能够较好地表现出海面风场的分布特点和变化特征。ERA5再分析资料具有较高的时空分辨率、较长的时间序列以及完整的数据记录,将其用于海上高风速事件的气候分析是可行的,且具有一定的优势。需要注意的是,ERA5再分析风速总体上存在低估实测风速的系统偏差,尤其是实测风速较大时,ERA5偏离于实测风速的现象更为明显。 展开更多
关键词 ERA5 ICOADS(International Comprehensive Ocean-Atmosphere data Set) 近地面10m风速 两洋一海 高风速事件
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Cross-Validation Convolution Neural Network-Based Algorithm for Automated Detection of Diabetic Retinopathy
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作者 S.Sudha A.Srinivasan T.Gayathri Devi 《Computer Systems Science & Engineering》 SCIE EI 2023年第5期1985-2000,共16页
The substantial vision loss due to Diabetic Retinopathy(DR)mainly damages the blood vessels of the retina.These feature changes in the blood vessels fail to exist any manifestation in the eye at its initial stage,if t... The substantial vision loss due to Diabetic Retinopathy(DR)mainly damages the blood vessels of the retina.These feature changes in the blood vessels fail to exist any manifestation in the eye at its initial stage,if this problem doesn’t exhibit initially,that leads to permanent blindness.So,this type of disorder can be only screened and identified through the processing of fundus images.The different stages in DR are Micro aneurysms(Ma),Hemorrhages(HE),and Exudates,and the stages in lesion show the chance of DR.For the advancement of early detection of DR in the eye we have developed the CNN-based identification approach on the fundus blood lesion image.The CNN-based automated detection of DR proposes the novel Graph cutter-built background and foreground superpixel segmentation technique and the foremost classification of fundus images feature was done through hybrid classifiers as K-Nearest Neighbor(KNN)classifier,Support Vector Machine(SVM)classifier,and Cascaded Rotation Forest(CRF)classifier.Over this classifier,the feature cross-validation made the classification more accurate and the comparison is made with the previous works of parameters such as specificity,sensitivity,and accuracy shows that the hybrid classifier attains excellent performance and achieves an overall accuracy of 98%.Among these Cascaded Rotation Forest(CRF)classifier has more accuracy than others. 展开更多
关键词 CNN networking SEGMENTATION hybrid classifier data set CROSSVALIDATION fundus image
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Preliminary results of the High Energetic Particle Package on-board the China Seismo-Electromagnetic Satellite 被引量:5
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作者 Wei Chu JianPing Huang +5 位作者 XuHui Shen Ping Wang XinQiao Li ZhengHua An YanBing Xu XiaoHua Liang 《Earth and Planetary Physics》 2018年第6期489-498,共10页
The high energetic particle package(HEPP) on-board the China Seismo-Electromagnetic Satellite(CSES) was launched on February 2, 2018. This package includes three independent detectors: HEPP-H, HEPP-L, and HEPP-X. HEPP... The high energetic particle package(HEPP) on-board the China Seismo-Electromagnetic Satellite(CSES) was launched on February 2, 2018. This package includes three independent detectors: HEPP-H, HEPP-L, and HEPP-X. HEPP-H and HEPP-L can detect energetic electrons from 100 keV to approximately 50 MeV and protons from 2 MeV to approximately 200 MeV. HEPP-X can measure solar X-rays in the energy range from 1 keV to approximately 20 keV. The objective of the HEPP payload was to provide a survey of energetic particles with high energy, pitch angle, and time resolutions in order to gain new insight into the space radiation environments of the near-Earth system. Particularly, the HEPP can provide new measurements of the magnetic storm related precipitation of electrons in the slot region, and the dynamics of radiation belts. In this paper, the HEPP scientific data sets are described and initial results are provided.The scientific data can show variations in the flux of energetic particles during magnetic storms. 展开更多
关键词 CSES energetic particles HEPP data sets data quality preliminary results
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Coronavirus Dynamics:The Undulating Playing Field
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作者 Bongs Lainjo 《Psychology Research》 2020年第3期118-123,共6页
The goal of the paper is to conduct an exploratory review and analyses of the dynamics of the pandemic focusing on two themes:pandemic morbidity and vulnerable populations.Method:Review of literature,anecdotal evidenc... The goal of the paper is to conduct an exploratory review and analyses of the dynamics of the pandemic focusing on two themes:pandemic morbidity and vulnerable populations.Method:Review of literature,anecdotal evidence,and reports on the morbidity of COVID-19;including scope of its devastating effects in selected countries.Findings:The devastating effects of the coronavirus are felt across different vulnerable populations.These include the elderly,front line workers,marginalized communities,visible minorities,and more.Inadequate and sometimes conflicting remarks by“experts”have only contributed in exacerbating the confusion in the general population.However,compassion and empathy from different communities have had positive effects on mitigating some of the health outcomes like mental health and other health-related effects of the pandemic.Institutional support needs to be strengthened,especially with regard to individual risks and supply chain coordination:personal protection equipment(PPE),masks,swabs,reagents,etc.The challenge in Africa is especially daunting,because of limited and inadequate financial resources and infrastructure,as confirmed by the health budget allocations as a percentage of their respective GDP(gross domestic product).Discussion:The effects of the COVID-19 are producing unprecedented and catastrophic outcomes in many countries.These have been exacerbated by the level of unpreparedness and inadequate degrees of prevention and intervention strategies.With a few exceptions,the common and current intervention approach is driven by many unknowns including compilation of relevant reliable and compelling data sets.Vulnerable communities continue to suffer most:a situation that is highlighted in this essay as one attempt to remind institutions of their duty to provide appropriate support,including compassion and empathy to these populations.The repercussions of no or inadequate action are numerous,significant,and mind-boggling with unpredictable future outcomes and possible dire consequences.The continuous carnage caused by COVID-19 is a wake-up call reminding all stakeholders(public and private institutions)that once again the inequality infiltrating vulnerable populations needs to be effectively addressed with emphasis on affordability,improved quality of life,and an inclusive long-term strategic plan.Ubiquitous and inadequate supply chain coordination mechanisms have been a major deterrent towards mitigating the effects of this coronavirus pandemic. 展开更多
关键词 coronavirus pandemic front line workers vulnerable populations compassion and empathy supply chain coordination unprecedented future outcomes relevant and compelling data sets protective personal equipment(PPE)
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Application of Self-Organizing Feature Map Neural Network Based on K-means Clustering in Network Intrusion Detection 被引量:5
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作者 Ling Tan Chong Li +1 位作者 Jingming Xia Jun Cao 《Computers, Materials & Continua》 SCIE EI 2019年第7期275-288,共14页
Due to the widespread use of the Internet,customer information is vulnerable to computer systems attack,which brings urgent need for the intrusion detection technology.Recently,network intrusion detection has been one... Due to the widespread use of the Internet,customer information is vulnerable to computer systems attack,which brings urgent need for the intrusion detection technology.Recently,network intrusion detection has been one of the most important technologies in network security detection.The accuracy of network intrusion detection has reached higher accuracy so far.However,these methods have very low efficiency in network intrusion detection,even the most popular SOM neural network method.In this paper,an efficient and fast network intrusion detection method was proposed.Firstly,the fundamental of the two different methods are introduced respectively.Then,the selforganizing feature map neural network based on K-means clustering(KSOM)algorithms was presented to improve the efficiency of network intrusion detection.Finally,the NSLKDD is used as network intrusion data set to demonstrate that the KSOM method can significantly reduce the number of clustering iteration than SOM method without substantially affecting the clustering results and the accuracy is much higher than Kmeans method.The Experimental results show that our method can relatively improve the accuracy of network intrusion and significantly reduce the number of clustering iteration. 展开更多
关键词 K-means clustering self-organizing feature map neural network network security intrusion detection NSL-KDD data set
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Discrete rough set analysis of two different soil-behavior-induced landslides in National Shei-Pa Park,Taiwan 被引量:4
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作者 Shih-Hsun Chang Shiuan Wan 《Geoscience Frontiers》 SCIE CAS CSCD 2015年第6期807-816,共10页
The governing factors that influence landslide occurrences are complicated by the different soil conditions at various sites.To resolve the problem,this study focused on spatial information technology to collect data ... The governing factors that influence landslide occurrences are complicated by the different soil conditions at various sites.To resolve the problem,this study focused on spatial information technology to collect data and information on geology.GIS,remote sensing and digital elevation model(DEM) were used in combination to extract the attribute values of the surface material in the vast study area of SheiPa National Park,Taiwan.The factors influencing landslides were collected and quantification values computed.The major soil component of loam and gravel in the Shei-Pa area resulted in different landslide problems.The major factors were successfully extracted from the influencing factors.Finally,the discrete rough set(DRS) classifier was used as a tool to find the threshold of each attribute contributing to landslide occurrence,based upon the knowledge database.This rule-based knowledge database provides an effective and urgent system to manage landslides.NDVI(Normalized Difference Vegetation Index),VI(Vegetation Index),elevation,and distance from the road are the four major influencing factors for landslide occurrence.The landslide hazard potential diagrams(landslide susceptibility maps) were drawn and a rational accuracy rate of landslide was calculated.This study thus offers a systematic solution to the investigation of landslide disasters. 展开更多
关键词 Landslide data mining Discrete rough sets Taiwan
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Application of Weighted Cross-Entropy Loss Function in Intrusion Detection 被引量:2
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作者 Ziyun Zhou Hong Huang Binhao Fang 《Journal of Computer and Communications》 2021年第11期1-21,共21页
The deep learning model is overfitted and the accuracy of the test set is reduced when the deep learning model is trained in the network intrusion detection parameters, due to the traditional loss function convergence... The deep learning model is overfitted and the accuracy of the test set is reduced when the deep learning model is trained in the network intrusion detection parameters, due to the traditional loss function convergence problem. Firstly, we utilize a network model architecture combining Gelu activation function and deep neural network;Secondly, the cross-entropy loss function is improved to a weighted cross entropy loss function, and at last it is applied to intrusion detection to improve the accuracy of intrusion detection. In order to compare the effect of the experiment, the KDDcup99 data set, which is commonly used in intrusion detection, is selected as the experimental data and use accuracy, precision, recall and F1-score as evaluation parameters. The experimental results show that the model using the weighted cross-entropy loss function combined with the Gelu activation function under the deep neural network architecture improves the evaluation parameters by about 2% compared with the ordinary cross-entropy loss function model. Experiments prove that the weighted cross-entropy loss function can enhance the model’s ability to discriminate samples. 展开更多
关键词 Cross-Entropy Loss Function Visualization Analysis Intrusion Detection KDD data Set ACCURACY
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Early Nutrient Diagnosis of Kentucky Bluegrass Combining Machine Learning and Compositional Methods
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作者 Abdo Badra Léon Etienne Parent 《American Journal of Plant Sciences》 CAS 2022年第9期1247-1260,共14页
Kentucky bluegrass (Poa pratensis L.) is the most common perennial turfgrass species grown on playgrounds, municipal and residential lawn areas, and golf tees, fairways and roughs. Fertilization is the most efficient ... Kentucky bluegrass (Poa pratensis L.) is the most common perennial turfgrass species grown on playgrounds, municipal and residential lawn areas, and golf tees, fairways and roughs. Fertilization is the most efficient way to improve and maintain turfgrass aesthetic quality. Tissue diagnosis can guide fertilization, but tissue concentration ranges are biased by not taking into consideration nutrient inter-relationships, carryover effects and other key features. The centered log-ratio transformation reflects nutrient interactions in plants and avoids statistical biases. Machine learning (ML) models relate the target variable to the key features ex ante, and can predict future events from prior knowledge. The objective of his study was to predict turfgrass quality from key features and rank nutrients in the order of their limitations. The experimental setup comprised four N, three P, and four K rates applied on permanent plots during three consecutive years. Soils were a loam and an USGA sand. Eleven elements (N, S, P, K, Ca, Mg, B, Cu, Zn, Mn, Fe) were quantified in clippings collected during spring, summer and autumn every year. Turfgrass quality was categorized as target variable by color rating. Concentrations were centered log-ratioed (clr) partitioned into four quadrants in the confusion matrix generated by the xgboost ML model. The area under curve (AUC) and model accuracy were high to predict turfgrass color from the nutrient analyses of clippings collected in the preceding season, facilitating the seasonal adjustment of the fertilization regime to sustain high turfgrass quality. We provide a computational example to run the ML model and rank nutrients in the order of their limitations. 展开更多
关键词 Centered Log Ratio data Set Machine Learning Turfgrass Foliage Color Turfgrass Shoot Density Xgboost
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Pivot Points in Bivariate Linear Regression
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作者 Carl V. Lutzer David L. Farnsworth 《Open Journal of Statistics》 2021年第3期393-399,共7页
There are little-noticed points in the plane, which are artifacts of linear regression. The points, which are called pivot points, are the intersections of sets of regression lines. We derive the coordinates of the pi... There are little-noticed points in the plane, which are artifacts of linear regression. The points, which are called pivot points, are the intersections of sets of regression lines. We derive the coordinates of the pivot point and explain its sources. We show how a pivot point arises in a certain notable data set, which has been analyzed often for points of high leverage. We obtain the application of pivot points that shortens calculations when updating a set of bivariate observations by adding a new point. 展开更多
关键词 Augmented data Set Bilinear Regression Influence Leverage Pivot Point Updating a Regression Line
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