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Location Based Generalized Akash Distribution: Properties and Applications 认领
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作者 Ramajeyam Tharshan Pushpakanthie Wijekoon 《统计学期刊(英文)》 2020年第2期163-187,共25页
In recent years, several statistical finite mixture models have been proposed to model the lifetime data with heterogeneity. The Lindley distribution has been highlighted by many authors for these types of lifetime da... In recent years, several statistical finite mixture models have been proposed to model the lifetime data with heterogeneity. The Lindley distribution has been highlighted by many authors for these types of lifetime data analysis. This paper introduces a new Lindley family distribution called location-based generalized Akash distribution (NGAD) with monotonic increasing and bathtub?failure rates. The density function of NGAD is flexible to cover the left-skewed, right-skewed and symmetrical shapes with different tail-weights. Its fundamental structural properties and its ability to provide a suitable statistical model for various types of data sets are studied. The maximum likelihood (ML) method is used to estimate its unknown parameters and the performance of ML estimates are examined by a simulation study. Finally, several real-data sets with different characteristics are used to illustrate its flexibility. It is observed that NGAD provides a better fit than some other existing modified Lindley distributions. 展开更多
关键词 Lindley DISTRIBUTION Akash DISTRIBUTION MIXTURE
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Improving the Performance of Fixed-Bed Catalytic Reactors by Innovative Catalyst Distribution 认领
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作者 Violeta Alejandra Chichique Martínez Farhang Shadman 《应用数学与应用物理(英文)》 2020年第4期672-683,共12页
A comprehensive mathematical model is developed to simulate the interactions of the complex processes that take place in typical catalytic chemical reactors. This mathematical model includes correlations representing ... A comprehensive mathematical model is developed to simulate the interactions of the complex processes that take place in typical catalytic chemical reactors. This mathematical model includes correlations representing various modes of mass transport and chemical reactions. To illustrate the application and value of this approach for reactor optimizations, the model is applied to the case of series reactions with a desirable intermediate compound and the risk of degradation of this compound if the process conditions are not optimized. The modeling results show that in such cases, which are very common in practice, replacing the conventional uniform catalyst distribution with a novel non-uniform distribution will significantly improve the performance of the reactor and the production of the desirable compound. Various catalyst distribution options are compared, and a novel non-uniform loading of catalyst is identified that gives a much better performance compared to the conventional approach. The model is versatile and useful for both the design as well as the optimization of the catalytic fixed-bed reactors in a wide variety of reactor and reaction conditions. 展开更多
关键词 CATALYST Reactor Optimization Series REACTIONS UNIFORM CATALYST DISTRIBUTION NON-UNIFORM CATALYST DISTRIBUTION CATALYST DEACTIVATION
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Distribution of Ag(I), Li(I)-Cs(I) Picrates, and Na(I) Tetraphenylborate with Differences in Phase Volume between Water and Diluents 认领
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作者 Satoshi Ikeda Saya Morioka Yoshihiro Kudo 《美国分析化学(英文)》 2020年第1期25-46,共22页
Ionic strength conditions in distribution experiments with single ions are very important for evaluating their distribution properties. Distribution experiments of picrates (MPic) with M = Ag(I) and Li(I)-Cs(I) into o... Ionic strength conditions in distribution experiments with single ions are very important for evaluating their distribution properties. Distribution experiments of picrates (MPic) with M = Ag(I) and Li(I)-Cs(I) into o-dichlorobenzene (oDCBz) were performed at 298 K by changing volume ratios (Vorg/V) between water and oDCBz phases, where “org” shows an organic phase. Simultaneously, an analytic equation with the Vorg/V variation was derived in order to analyze such distribution systems. Additionally, the AgPic distribution into nitrobenzene (NB), dichloromethane, and 1,2-dichloroethene (DCE) and the NaB(C6H5) 4 (=NaBPh4) one into NB and DCE were studied at 298 K under the conditions of various Vorg/V values. So, extraction constants (Kex) for MPic into the org phases, their ion-pair formation constants (KMA,org) for MA = MPic in the org ones, and standard distribution constants () for the M(I) transfers between the water and org bulk phases with M = Ag and Li-Cs were determined at the distribution equilibrium potential (dep) of zero V between the bulk phases and also the Kex (NaA), KNaA,org, and values were done at A-=BPh-4. Here, the symbols Kex, KMA,org, and or were defined as [MA] org/[M+][A-], [MA] org/[M+]org [A-]org, and [M+]org/[M+] or [A-]org/[A-] at dep = 0, respectively. Especially, the ionic strength dependences of Kex and KMPic,org were examined at M = Li(I)-K(I) and org = oDCBz. From above, the conditional distribution constants, KD,BPh4 and KD,Cs, were classified by checking the experimental conditions of the I, Iorg, and dep values. 展开更多
关键词 Standard DISTRIBUTION Constants VOLUME Ratios DISTRIBUTION Equilibrium Potentials Ionic Strength Dependence Extraction CONSTANT Ion-Pair Formation CONSTANT o-Dichlorobenzene
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Assessment of Sediment and Benthic Macrofauna Distribution at Dar es Salaam Harbour Channel 认领
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作者 Benard Mwakisunga John F. Machiwa Harishchandra Bhagwanji Pratap 《地球科学和环境保护期刊(英文)》 2020年第3期133-147,共15页
Sediment and macrobenthic fauna distribution at Dar es Salaam harbour channel were investigated to attest the influence of sediment grain size distribution and total organic carbon contents on benthic macrofauna domin... Sediment and macrobenthic fauna distribution at Dar es Salaam harbour channel were investigated to attest the influence of sediment grain size distribution and total organic carbon contents on benthic macrofauna dominance and diversity. Sampling campaign was conducted from January to April, 2019 in 25 sampling stations along the channel. Sediment grain sizes ranged between 0.7405 and 0.00273 mm with an average of 0.0804 mm classified as medium silt. Sediment distribution showed an onshore-offshore pattern consisting of fine dark clay-silt sediments in the southern part of the harbour close to Mwalimu Nyerere Bridge, medium (sandy) at the harbour and coarse sandy offshore. Five classes of macrofauna were identified with sedentary Polychaetes (Diopatra cuprea) found in tubes and free forms being dominant in most of the sediment types, however more abundant in clay-silt. High species diversity index values were encountered in sediments with medium total organic carbon (TOC) and sediment grain sizes (sand-silt). Apparently, low species similarity indices were observed in all sediment type indicating significant dissimilarities in species composition among sediment grain sizes. Thus, the distribution of benthic macrofauna species along Dar es Salaam harbour channel is strongly influenced by the sediment grain sizes and organic carbon contents in sediments. 展开更多
关键词 SEDIMENT Grain Size DISTRIBUTION BENTHIC MACROFAUNA Diversity and ABUNDANCE Total Organic Carbon DISTRIBUTION Dar es Salaam HARBOR Channel
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Flumetralin and dimethyl piperidinium chloride alter light distribution in cotton canopies by optimizing the spatial configuration of leaves and bolls 认领
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作者 LIANG Fu-bin YANG Cheng-xun +3 位作者 SUI Long-long XU Shou-zhen YAO He-sheng ZHANG Wang-feng 《农业科学学报:英文版》 SCIE CAS CSCD 2020年第7期1777-1788,共12页
Plant growth regulators(PGRs)are frequently used to adjust cotton growth and development.The objectives of this study were to determine how PGRs affect plant morphology,light distribution and the spatial distribution ... Plant growth regulators(PGRs)are frequently used to adjust cotton growth and development.The objectives of this study were to determine how PGRs affect plant morphology,light distribution and the spatial distribution of leaves and bolls within the cotton canopy.The field experiments were carried out at Shihezi(Xinjiang Uyghur Autonomous Region,China)in 2014 and 2015.The experiment included two PGR treatments:(i)flumetralin(active ingredient(a.i),N-N-ethy)-2,6-dinitro-4-aniline and(i)mepiquat chloride(ai,1-dimethyl-piperidiniuchloride)plus flumetralin.No PGR(manual topping)was applied in the control treatment.The chemically-topped plants were taller and had more main stem internodes than the manually-topped plants.Furthermore,the PGRs significantly reduced the length of fruiting branches in the upper canopy,resulting in a more compact canopy.The maximum leaf area index was signifcantly greater in the chemically-topped treatments than that in the control.In particular,the PGRs increased leaf area index by 25%in the upper canopy.The leaf area duration was also longer in the chemically-topped treatments than in the control.Compared with the control,the chemically-topped treatments increased canopy diffuse non-interceptance by 35.75%in the upper canopy layer,while reducing the fraction of intercepted photosynthetically active radiation by 14.45%in the upper canopy layer.Light transmittance in the upper and middle canopy layers was greater in the chemically-topped treatments than in the control,which increased boll numbers in both the upper canopy and the middle canopy.However,the chemically-topped treatments resulted in less light-leakage through the lower canopy layer during the late growth stages,which had a tendency to increase boll numbers in the whole canopy.In summary,the PGRs optimized canopy shape,light distribution and the spatial distribution of bolls and leaves. 展开更多
关键词 COTTON chemical topping leaf spatial distribution light distribution boll spatial distribution
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Prediction of particle size and layer-thickness distributions in a continuous horizontal fluidized-bed coating process 认领
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作者 P.Bachmann K.Chen +1 位作者 A.Buck E.Tsotsas 《颗粒学报:英文版》 SCIE EI CAS CSCD 2020年第3期1-12,共12页
To predict the particle size and layer-thickness distributions(LTDs)in a continuously operated horizontal fluidized-bed granulation process,two alternative models were considered.A one-dimensional two-zone model was p... To predict the particle size and layer-thickness distributions(LTDs)in a continuously operated horizontal fluidized-bed granulation process,two alternative models were considered.A one-dimensional two-zone model was proposed,which describes with population-balance equations the particle growth in a spraying zone that is separated from the drying zone.The residence-time distribution(RTD)was calculated from a literature correlation and was coupled with a population-balance model via a tank-in-series model with reflux.A two-dimensional,one-zone population-balance model,which was based directly on the RTD and the feed particle-size distribution(PSD)was also used.Granulation experiments were conducted and analyzed microscopically and with a camera optical device to determine the sample PSDs.LTDs over the particle population were derived from the PSDs and were analyzed directly by micro-computer-tomography.To compare the simulated data with the experimentally determined distributions,the PSDs were converted to LTDs.The good agreement shows that both methods are suitable to determine the PSD from an RTD of an arbitrary granulation process in a horizontal fluidized bed.Improvement appears necessary with regards to the LTD spread. 展开更多
关键词 Fluidized bed Continuous process Coating Residence-time distribution Particle-size distribution Layer-thickness distribution
Global Sensitivity Analysis in Physiological Systems 认领
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作者 Tahmineh Azizi Robert Mugabi 《应用数学(英文)》 2020年第3期119-136,共18页
Pharmacokinetic models are mathematical models which provide insights into the interaction of chemicals with biological processes. During recent decades, these models have become central of attention in industry that ... Pharmacokinetic models are mathematical models which provide insights into the interaction of chemicals with biological processes. During recent decades, these models have become central of attention in industry that caused to do a lot of efforts to make them more accurate. Current work studies the process of drug and nanoparticle (NPs) distribution throughout the body which consists of a system of ordinary differential equations. We use a tri-compartmental model to study the perfusion of NPs in tissues and a six-compartmental model to study drug distribution in different body organs. We have performed global sensitivity analysis by LHS Monte Carlo method using PRCC. We identify the key parameters that contribute most significantly to the absorption and distribution of drugs and NPs in different organs in body. 展开更多
关键词 Global Sensitivity Analysis LATIN HYPERCUBE Sampling (LHS) Partial RANK Correlation Coefficient (PRCC) PHYSIOLOGICAL Systems Drug and NPS Distribution
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关于众包物流与配送的探讨 认领 被引量:1
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作者 李叶 《物流工程与管理》 2020年第3期17-19,共3页
随着电商的发展壮大,物流需求也越来越高,物流需求的增加带来了一系列问题,尤其体现在物流配送方面。而不断发展的物流业,也在不断进行着创新,众包物流方式应运而生。文中第一部分介绍了配送的现状及目前存在的问题,分析目前物流配送所... 随着电商的发展壮大,物流需求也越来越高,物流需求的增加带来了一系列问题,尤其体现在物流配送方面。而不断发展的物流业,也在不断进行着创新,众包物流方式应运而生。文中第一部分介绍了配送的现状及目前存在的问题,分析目前物流配送所面临的困局;第二部分介绍了众包物流及其优势和存在问题;第三部分探讨了能否利用众包物流来解决目前存在的配送问题。通过分析探讨,得出结论:众包物流要在政策约束及奖惩措施的激励下合法开展,在此基础上可以部分解决农村配送的问题并可以成为城市配送旺季的补充力量。众包物流的作用不止于此,未来,或许可以在生鲜配送等方面发挥更大的作用、解决更多的问题。 展开更多
关键词 配送 众包物流 农村配送
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State Estimation of Distribution Network Considering Data Compatibility 认领
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作者 Shengtao Wu Yan Li 《能源与动力工程(英文)》 2020年第4期73-83,共11页
Considering that the measurement devices of the distribution network are becoming more and more abundant, on the basis of the traditional Supervisory Control And Data Acquisition (SCADA) measurement system, Phasor mea... Considering that the measurement devices of the distribution network are becoming more and more abundant, on the basis of the traditional Supervisory Control And Data Acquisition (SCADA) measurement system, Phasor measurement unit (PMU) devices are also gradually applied to the distribution network. So when estimating the state of the distribution network, the above two devices need to be used. However, because the data of different measurement systems are different, it is necessary to balance this difference so that the data of different systems can be compatible to achieve the purpose of effective utilization of the estimated power distribution state. To this end, this paper starts with three aspects of data accuracy of the two measurement systems, data time section and data refresh frequency to eliminate the differences between system data, and then considers the actual situation of the three-phase asymmetry of the distribution network. The three-phase state estimation equations are constructed by the branch current method, and finally the state estimation results are solved by the weighted least square method. 展开更多
关键词 Distribution Network STATE ESTIMATION DATA Compatibility Branch CURRENT Method
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Using Confidence Statements to Ordering Medians: A Simple Microarray Nonparametric Analysis 认领
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作者 Carlos A. de B. Pereira Adriano Polpo 《统计学期刊(英文)》 2020年第1期154-162,共9页
Comparing two samples about corresponding parameters of their respective populations is an old and classical statistical problem. In this paper, we present a simple yet effective tool to compare two samples through th... Comparing two samples about corresponding parameters of their respective populations is an old and classical statistical problem. In this paper, we present a simple yet effective tool to compare two samples through their medians. We calculate the confidence of the statement “the median of the first population is strictly smaller (larger) than the median of the second.” We analyze two real data sets and empirically demonstrate the quality of the confidence for such a statement. This confidence in the order of the medians is to be seen as a pre-analysis tool that can provide useful insights for comparing two or more populations. The method is entirely based on their exact distribution with no need for asymptotic considerations. We also provide the Quor statistical software, an R package that implements the ideas discussed in this work. 展开更多
关键词 Significance Test Comparison of Two Samples CONFIDENCE INTERVAL Based on the BINOMIAL Distribution
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配给技术提升影响企业创新模式转变的机制研究 认领
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作者 孙兰 李美娟 《企业经济》 北大核心 2020年第6期54-62,共9页
配给(Distribution),定义为将产品配送给客户,是经济活动中的一个重要组成部分。配给技术的提升,不仅通过不断降低配给成本而促进经济增长,也对塑造经济增长创新模式起着重要的作用。针对这一问题,采用一个两阶段双寡头古诺竞争模型研... 配给(Distribution),定义为将产品配送给客户,是经济活动中的一个重要组成部分。配给技术的提升,不仅通过不断降低配给成本而促进经济增长,也对塑造经济增长创新模式起着重要的作用。针对这一问题,采用一个两阶段双寡头古诺竞争模型研究在市场竞争相互作用的机制下,配给技术提升如何影响企业创新模式的选择。结果表明:一方面配给技术的提升增加企业创新R&D的投入,另一方面有助于企业从流程(工艺)创新向质量不断提高的产品创新模式转变。因此,我国应不断加强高铁等运输基础设施建设和5G网络、数据中心等新型基础设施建设,使配给技术不断提高,从而激励企业从量的竞争不断向质的竞争转变,以助于实现我国高质量经济增长模式的转变。 展开更多
关键词 配给 配给技术 产品创新 流程(工艺)创新 高质量发展
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Frequency–magnitude of landslides affected by the 27–29 November 2017 Tropical Cyclone Cempaka in Pacitan, East Java 认领
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作者 SAMODRA Guruh NGADISIH Ngadisih +3 位作者 MALAWANI Mukhamad Ngainul MARDIATNO Djati CAHYADI Ahmad NUGROHO Ferman Setia 《山地科学学报:英文版》 SCIE CSCD 2020年第4期773-786,共14页
Tropical cyclone(TC) Cempaka which occurred on 27–29 November 2017 has caused floods, landslides, and strong winds in certain areas of Java Island. Pacitan Regency was the most severely affected by TC Cempaka. The la... Tropical cyclone(TC) Cempaka which occurred on 27–29 November 2017 has caused floods, landslides, and strong winds in certain areas of Java Island. Pacitan Regency was the most severely affected by TC Cempaka. The landslide frequency–area distribution curve of event inventory i.e. TC Cempaka can help to understand landslide susceptibility, hazard, vulnerability, and risk. Landslides were identified by using a local government database and by comparing pre-and post-event high-resolution satellite imageries. Field investigation was carried out in March 2018 to November 2018 to verify the landslide location and update the information. Power law, inverse gamma, and double Pareto model were employed to describe the frequency–magnitude of landslide(mLS) triggered by TC Cempaka. The exponent β values of power law, inverse gamma, and double Pareto were 2.6±0.28(fitted for 8.5% of dataset), 2.2±0.08(fitted for 83% of dataset), and 2.3±0.09(best fitted for dataset), respectively. The P-values were 0.51, 0.67, and 0.91 for power law, inverse gamma, and double Pareto, respectively. This study revealed that rollover occurred at 200 and 300 m2 for double Pareto and inverse gamma, respectively. The cutoff points totaled 1096.49 ± 236.44 and 7235.4 ± 1896.7 m2 for double Pareto and power law, respectively. Rollover phenomenon was real and existed in the dataset because it was far from the minimum resolvable size of the landslide that the authors can delineate from the satellite images. mLS for Pacitan was distributed at around 2 to 4. The magnitude of large landslides was 3.2, that of medium landslides was less than 3, and that of small landslides was almost 4. Numerical estimation calculated a fixed mLS=3.01. Comparison analysis of β values obtained from several landslide inventories triggered by heavy rainfall suggests that the variability of β is related to the intensity and duration of rainfall. Triggering events, such as intensity and duration of rainfall, affect the proportion of large landslides that occur i 展开更多
关键词 LANDSLIDE Tropical cyclone LANDSLIDE MAGNITUDE FREQUENCY DISTRIBUTION Area DISTRIBUTION Pacitan REGENCY
Study on a Stochastic Avian Influenza Epidemic Model with Generalized Incidence Rate 认领
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作者 Shasha Ma 《应用科学(英文)》 2020年第5期228-245,共18页
Avian Influenza, with a high mortality rate in human population, is considered to be one of the most significant potential threats to human beings. Based on a recent avian influenza SI-SIR model with logistic growth f... Avian Influenza, with a high mortality rate in human population, is considered to be one of the most significant potential threats to human beings. Based on a recent avian influenza SI-SIR model with logistic growth for birds, we propose a stochastic model with generalized incidence rate. For the stochastic avian-only system, sufficient conditions for the extinction of infected birds are established, and the existence of a unique ergodic stationary distribution is also obtained. For the stochastic avian-human system, a threshold number is established, and hence the extinction of disease is investigated. From the viewpoint of biology, the noise intensity in the infected birds plays a key role in the evolutionary dynamics. Moreover, we also analyze the asymptotic behavior around the endemic equilibrium of the corresponding deterministic model. 展开更多
关键词 AVIAN INFLUENZA EXTINCTION ERGODIC STATIONARY Distribution ASYMPTOTIC Behavior
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Bayesian Regularized Quantile Regression Analysis Based on Asymmetric Laplace Distribution 认领
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作者 Qiaoqiao Tang Haomin Zhang Shifeng Gong 《应用数学与应用物理(英文)》 2020年第1期70-84,共15页
In recent years, variable selection based on penalty likelihood methods has aroused great concern. Based on the Gibbs sampling algorithm of asymmetric Laplace distribution, this paper considers the quantile regression... In recent years, variable selection based on penalty likelihood methods has aroused great concern. Based on the Gibbs sampling algorithm of asymmetric Laplace distribution, this paper considers the quantile regression with adaptive Lasso and Lasso penalty from a Bayesian point of view. Under the non-Bayesian and Bayesian framework, several regularization quantile regression methods are systematically compared for error terms with different distributions and heteroscedasticity. Under the error term of asymmetric Laplace distribution, statistical simulation results show that the Bayesian regularized quantile regression is superior to other distributions in all quantiles. And based on the asymmetric Laplace distribution, the Bayesian regularized quantile regression approach performs better than the non-Bayesian approach in parameter estimation and prediction. Through real data analyses, we also confirm the above conclusions. 展开更多
关键词 ASYMMETRIC LAPLACE Distribution Gibbs Sampling Adaptive Lasso Lasso BAYESIAN REGULARIZATION QUANTILE Regression
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Avian Community Density and Distribution Patterns among Nicaraguan Conventional and Organic Shade-Coffee Plantations 认领
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作者 Wayne J. Arendt R. Cary Tuckfield +4 位作者 Juan Carlos Martínez-Sánchez Jennifer L. Reidy Frank R. Thompson III Joseph M. Wunderle Jr. José Manuel Zolotoff 《农业科学(英文)》 2020年第1期27-53,共27页
We used a distance-sampling survey method and multivariate statistics to obtain a unique estimate of bird species density and seasonal variation in shade-coffee plantations. Our aim was to determine which cultivation ... We used a distance-sampling survey method and multivariate statistics to obtain a unique estimate of bird species density and seasonal variation in shade-coffee plantations. Our aim was to determine which cultivation practices among plantations contribute most to bird abundance. We conducted avian species counts at 200 points distributed across 10 shade-coffee plantations bordering the lower slopes of the Mombacho Volcano Natural Reserve, in western Nicaragua. We measured vegetation structure (coffee plants and overstory). We used principal components analysis (PCA) among 14 habitat variables to derive a single phyto-geoclimate summary measure (PGSM). We also used PCA to derive an avian abundance summary measure (AASM) from three bird survey variables, which proved to be a good predictor of bird density. We found higher bird species densities (AASM) in organic and traditional polyculture shade coffee plantations whose structurally complex and diverse overstory could be verified by PGSM. However, this finding was true only for birds that were habitat specialists. Our results provide further evidence for promoting organic coffee cultivation practices that maintain a structurally diverse overstory and help retain avian species richness and abundance in coffee plantations. 展开更多
关键词 Bird Density COFFEE Cultivation Practices MONOCULTURE ORGANIC POLYCULTURE Spatial Distribution Species Richness
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Marginal Bottleneck Identification in Power System Considering Correlated Wind Power Prediction Errors 认领
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作者 Bin Liu Ke Meng +1 位作者 Zhao Yang Dong Wang Zhang 《现代电力系统与清洁能源学报(英文)》 SCIE EI CSCD 2020年第1期187-192,共6页
This letter investigates how to identify the marginal bottleneck,which is defined as the constraint most likely to be violated with the increasing wind generation uncertainty of power system in real-time dispatch.The ... This letter investigates how to identify the marginal bottleneck,which is defined as the constraint most likely to be violated with the increasing wind generation uncertainty of power system in real-time dispatch.The presented method takes the correlation of wind power prediction error(WPPE)into account,leading to an ellipsoidal formulation of wind power generation region(WGR).Based on constructed WGR,the identification procedure is formulated as a max-max-min problem,which is solved by the algorithm based on iteration linear program with the proposed method to select appropriate initial points of WPPE.Finally,two cases are tested,demonstrating the efficacy and efficiency of the procedure to identify marginal bottleneck. 展开更多
关键词 BOTTLENECK ELLIPTICAL DISTRIBUTION HYPERBOLIC DISTRIBUTION wind power ACCOMMODATION
Generalized Weighted Exponential-Gompertez Distribution 认领
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作者 Abd El-Moneim A. M. Teamah Hanan H. El-Damrawy Shaimaa M. T. Swan 《应用数学(英文)》 2020年第2期97-118,共22页
Statistical analysis of lifetime data is a significant topic in social sciences, engineering, reliability, biomedical and others. We use the generalized weighted exponential distribution, as a generator to introduce a... Statistical analysis of lifetime data is a significant topic in social sciences, engineering, reliability, biomedical and others. We use the generalized weighted exponential distribution, as a generator to introduce a new family called generalized weighted exponential-G family, and apply this new generator to provide a new distribution called generalized weighted exponential gombertez distribution. We investigate some of its properties, moment generating function, moments, conditional moments, mean residual lifetime, mean inactivity time, strong mean inactivity time, Rényi entropy, Lorenz curves and Bonferroni. Furthermore, in this model, we estimate the parameters by using maximum likelihood method. We apply this model to a real data-set to show that the new generated distribution can produce a better fit than other classical lifetime models. 展开更多
关键词 Generalized Weighted Exponential-G Family Gombertez DISTRIBUTION Bonferroni and LORENZ Curves Conditional MOMENTS Mean INACTIVITY Time Mean Residual Lifetime Maximum Likelihood ESTIMATORS
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Adaptive Sparse Group Variable Selection for a Robust Mixture Regression Model Based on Laplace Distribution 认领
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作者 Jiangtao Wang Wanzhou Ye 《理论数学进展(英文)》 2020年第1期39-55,共17页
The traditional estimation of Gaussian mixture model is sensitive to heavy-tailed errors;thus we propose a robust mixture regression model by assuming that the error terms follow a Laplace distribution in this article... The traditional estimation of Gaussian mixture model is sensitive to heavy-tailed errors;thus we propose a robust mixture regression model by assuming that the error terms follow a Laplace distribution in this article. And for the variable selection problem in our new robust mixture regression model, we introduce the adaptive sparse group Lasso penalty to achieve sparsity at both the group-level and within-group-level. As numerical experiments show, compared with other alternative methods, our method has better performances in variable selection and parameter estimation. Finally, we apply our proposed method to analyze NBA salary data during the period from 2018 to 2019. 展开更多
关键词 ROBUST MIXTURE Regression LAPLACE Distribution ADAPTIVE SPARSE GROUP Lasso
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Study on Backward Scattering Characteristics of Submicron Particles 认领
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作者 Keliang Hou Chunwei Wang Xiang Liu 《光学与光子学期刊(英文)》 2020年第5期79-87,共9页
In production and scientific research, the research on the characteristics of submicron particles has attracted extensive attention, which is of great significance to the development of industrial production, medical ... In production and scientific research, the research on the characteristics of submicron particles has attracted extensive attention, which is of great significance to the development of industrial production, medical and health inspection and other fields. In this paper, the characteristics of submicron particles are studied based on backlight scattering. By collecting the real-time waveform of the backscattering signal of particles with different particle sizes at different concentrations, the corresponding relationship between the particle concentration and the number of pulses was obtained. It is found that the peak value of the backscattered light energy has a good linear relationship with the particle size. The analysis of the signal distribution law of standard particle swarm with different particle size parameters found that it conformed to the lognormal distribution form. 展开更多
关键词 BACKWARD SCATTERING SUBMICRON PARTICLES LOGNORMAL DISTRIBUTION
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Understanding the role of interface in advanced semiconductor nanostructure and its interplay with wave function overlap 认领
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作者 Chenyuan Cai Yunhao Zhao +9 位作者 Faran Chang Xuebing Zhao Liting Yang Chongyun Liang Guowei Wang Zhichuan Niu Yi Shi Xianhu Liu Yuesheng Li Renchao Che 《纳米研究:英文版》 SCIE EI CAS CSCD 2020年第6期1536-1543,共8页
As the proportion of interfaces increases rapidly in nanomaterials,properties and quality of interfaces hugely impact the performance of advanced semiconductors.Here,the effect of interfaces is explored by comparative... As the proportion of interfaces increases rapidly in nanomaterials,properties and quality of interfaces hugely impact the performance of advanced semiconductors.Here,the effect of interfaces is explored by comparatively studying two InAs/AlSb superlattices with and without the thin InAsSb layers inserted inside each InAs layers.Through strain mapping,it indicates that the addition of interfaces leads to an increase of local strain both near interfaces and inside layers.Meantime,owing to the creation of hole potential wells within the original electron wells,the charge distribution undergoes an extra electron-hole alternating arrangement in the structure with inserted layers than the uninserted counterpart.Such a feature is verified to enhance electron-hole wave function overlap by theoretical simulations,which is a must for better optical performance.Furthermore,with an elaborate design of the inserted layers,the wave function overlap could be boosted without sacrificing other key device performances. 展开更多
关键词 interface engineering energy band alignment charge distribution strain distribution semiconductor multilayer nanostructures
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