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arXiv 2017年

作者： Huang, Jianhong Hu, Bin Skiba, Alexander N. School of Mathematics and Statistics Jiangsu Normal University Xuzhou221116 China Department of Mathematics and Technologies of Programming Francisk Skorina Gomel State University Gomel246019 Belarus

Let σ = {σi|i ∈ I} be a partition of the set of all primes P and G a finite group. Let σ(G) = {σi: σi∩ π(G) 6= Ø. A set H of subgroups of G is said to be a complete Hall σ-set of G if every member ≠ 1 of H is a Hall σi-subgroup of G for some i ∈ I and H contains exactly one Hall σi-subgroup of G for every i such that σi∈ σ (G). We say that G is σ-full if G possesses a complete Hall σ-set. A complete Hall σ-set H of G is said to be a σ-basis of G if every two subgroups A,B ∈ H are permutable, that is, AB = BA. In this paper, we study properties of finite groups having a σ-basis. In particular, we prove that if G has a a σ-basis, then G is generalized σ-soluble, that is, G has a complete Hall σ-set and for every chief factor H/K of G we have |σ (H/K)| ≤ 2. Moreover, answering to Problem 8.28 in [3], we prove the following Theorem A. Suppose that G is σ-full. Then every complete Hall σ-set of G forms a σ-basis of G if and only if G is generalized σ-soluble and for the automorphism group G/CG(H/K), induced by G on any its chief factor H/K, we have either σ (H/K) = σ (G/CG(H/K)) or σ (H/K) = {σi} and G/CG(H/K) is a σi∪ σj-group for some i ≠ j. Copyright © 2017, The Authors. All rights reserved.

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K-groups: A generalization of k-means clustering

arXiv

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arXiv 2017年

作者： Li, Songzi Rizzo, Maria L. Biostatistics and Programming Department Pharmaceutical Product Deparment LLC WilmingtonNC28401 Dept. of Mathematics & Statistics Bowling Green State University Bowling GreenOH43403 United States

We propose a new class of distribution-based clustering algorithms, called k-groups, based on energy distance between samples. The energy distance clustering criterion assigns observations to clusters according to a multi-sample energy statistic that measures the distance between distributions. The energy distance determines a consistent test for equality of distributions, and it is based on a population distance that characterizes equality of distributions. The k-groups procedure therefore generalizes the k-means method, which separates clusters that have different means. We propose two k-groups algorithms: k-groups by first variation;and k-groups by second variation. The implementation of k-groups is partly based on Hartigan and Wong's algorithm for k-means. The algorithm is generalized from moving one point on each iteration (first variation) to moving m (m > 1) points. For univariate data, we prove that Hartigan and Wong's k-means algorithm is a special case of k-groups by first variation. The simulation results from univariate and multivariate cases show that our k-groups algorithms perform as well as Hartigan and Wong's k-means algorithm when clusters are well-separated and normally distributed. Moreover, both k-groups algorithms perform better than k-means when data does not have a finite first moment or data has strong skewness and heavy tails. For non-spherical clusters, both k-groups algorithms performed better than k-means in high dimension, and k-groups by first variation is consistent as dimension increases. In a case study on dermatology data with 34 features, both k-groups algorithms performed better than k-means. Copyright © 2017, The Authors. All rights reserved.

关键词： Cluster analysis

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HEALTH OF SEXUAL MINORITY WOMEN CARING FOR ADULTS WITH CANCER VS OTHER DISEASES: AN INTERNET SURVEY

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Innovation in Aging 2018年第SUPPL_1期2卷 273–273页

作者： Fredman, L Clark, M Margolies, L Winter, M Boehmer, U Boston University School of Public Health University of Massachusetts Medical School National LGBT Cancer Network Statistical Programming School of Public Health - BEDAC - Statistics Community Health Sciences Department Boston University School of Public Health

Little is known about the health of sexual minority women caregivers, or vulnerable subgroups in this population. We compared self-rated health of caregivers to adults with cancer versus other conditions among 266 sexual/gender minority women who completed an internet survey during January 2018. Women were recruited via the National LGBT Cancer Network Facebook site. Eligibility included identifying as lesbian, gay, bisexual or transgender (LGBT), and providing care to an adult for > 2 hours/week. Respondents’ mean age was 38.0 (+ 8.4) years; 76% were white; 45% cared for a relative or friend with cancer, which were mainly breast (24%) and lung (26%) cancers, followed by lymphoma, colorectal, and prostate cancer. Other respondents cared for persons with dementia (29%), heart disease, aging-related disorders, mental illness, and AIDS (12%-23%). Cancer caregivers were significantly (p<0.05) more likely than other caregivers to be non-white, care for a spouse, live with the care recipient, and perform caregiving tasks >5 hours/day. They were more likely to rate their own health as fair/poor (43% vs. 12%), particularly if they helped a spouse with cancer (45%). In confounder-adjusted multinomial logistic regression analyses, cancer caregivers had higher odds than other caregivers of rating their health as fair/poor (adjusted odds ratio, aOR = 8.20, 95% confidence interval, CI= 3.26–20.61) or good (aOR = 1.97, CI = 0.89–4.34) versus excellent/very good (22% vs. 49%). In conclusion, LGBT women caregivers for persons with cancer had worse self-rated health and may be at risk of adverse health outcomes; these results merit further study.

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Fuzzy vs neural network models for environmental decision support system implementation aiming to standardise the multiparametric decision in a Drinking Water Plant with Electrodialysis Reversal 8

Fuzzy vs neural network models for environmental decision su...

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8th International Congress on Environmental Modelling and Software - Environmental Modelling and Software for Supporting a Sustainable Future, iEMSs 2016

作者： Dalmau, Montse Monclús, Hèctor Espasa, Joan Atanasova, Natasa Poch, Manel Emiliano, Pere Capdevila, Oriol González, Santiago Valero, Fernando Institute of the Environment University of Girona Girona CataloniaE-17003 Spain Logic and Programming Research Group Department of Computer Science Applied Mathematics and Statistics University of Girona Girona CataloniaE-17003 Spain ATLL-Concessionària de la Generalitat de Catalunya Sant Martí de l'Erm 30 Sant Joan Despí Barcelona CataloniaE08970 Spain

ISBN: (纸本)9788890357459

The development of an environmental decision support system (EDSS) by means of two different aims to support the operators' decisions in the drinking water treatment plant (DWTP), equipped with the biggest electrodialysis reversal (EDR) in the world. A fuzzy artificial neural network (ANN) modelling and adaptive network-based fuzzy inference system (ANFIS) have been compared for optimizing the decision: how to manage water blending ratios from EDR and conventional treatment of the drinking water plant, evaluating Llobregat River characteristics (inlet DWTP), current operating conditions of DWTP, weather conditions and distribution requirements on-line. This tool has been tested among 4,5 months in the facility, showing better tendencies regarding the ANFIS model in comparison to the ANN model. A further application of the ANN and ANFIS process models, tested and validated, will be integrated into a process-controlled architecture of the EDSS. © 2016 Environmental Modelling and Software for Supporting a Sustainable Future, Proceedings - 8th International Congress on Environmental Modelling and Software, iEMSs 2016. All rights reserved.

关键词： Fuzzy inference

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Automatic Fault Detection in WDM-PON with Tunable Photon Counting OTDR

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Journal of Lightwave Technology 2015年第24期33卷 5025-5031页

作者： Amaral, Gustavo C. Garcia, Joaquim D. Herrera, Luis E. Y. Temporão, Guilherme P. Urban, Patryk J. Von Der Weid, Jean Pierre Center for Telecommunications Studies Pontifical Catholic University of Rio de Janeiro Rio de Janeiro22451-900 Brazil Laboratory for Applied Mathematical Programming and Statistics Pontifical Catholic University of Rio de Janeiro Rio de Janeiro22451-900 Brazil Ericsson Research Ericsson AB Stockholm164 83 Sweden

An automatic fiber-optical fault analysis system making use of a tunable photon counting optical time-domain reflectometry (OTDR) (ν-OTDR) is proposed and demonstrated in a passive optical network testbed. The employment of the 1 trend filter as a signal processing tool enables the minimization of the intrinsic coherent random noise impact on the acquired data and also an automatic identification of fiber faults. A feedback loop between an FPGA-based acquisition unit and the filter's selections yields highly accurate automatic results and minute monitoring periods with ITU-T grid DWDM tunability, spatial resolution of 6 m and a measured 32 dB dynamic range. © 1983-2012 IEEE.

关键词： Reflectometers

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Change-Point Analysis of Survival Data with Application in Clinical Trials

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Open Journal of statistics 2014年第9期4卷 663-677页

作者： Xuan Chen Michael Baron Department of Biostatistics and Programming Sanofi Beijing China Department of Mathematics and Statistics American University Washington DC USA Department of Mathematical Sciences University of Texas at Dallas Richardson USA

Effects of many medical procedures appear after a time lag, when a significant change occurs in subjects’ failure rate. This paper focuses on the detection and estimation of such changes which is important for the evaluation and comparison of treatments and prediction of their effects. Unlike the classical change-point model, measurements may still be identically distributed, and the change point is a parameter of their common survival function. Some of the classical change-point detection techniques can still be used but the results are different. Contrary to the classical model, the maximum likelihood estimator of a change point appears consistent, even in presence of nuisance parameters. However, a more efficient procedure can be derived from Kaplan-Meier estimation of the survival function followed by the least-squares estimation of the change point. Strong consistency of these estimation schemes is proved. The finite-sample properties are examined by a Monte Carlo study. Proposed methods are applied to a recent clinical trial of the treatment program for strong drug dependence.

关键词： Change-Point Problem Failure Rate Kaplan-Meier Estimation Least Squares Estimation Maximum Likelihood Estimation Strong Consistency Survival Function

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Methods for Confidence Intervals for Vaccine Efficacy

Methods for Confidence Intervals for Vaccine Efficacy

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更好创新与全球健康——2013第五届世界疫苗大会

作者： Huiling Xiong Tian Dai Kerry Go Fabrice Bailleux Xiao Geng Andrew Dunning Head of Statistics and Programming Biometry China Sanofi Pateur

The large size and high cost of vaccine efficacy trials means that small improvements in statistical efficiency might have appreciable benefits in terms of sample size and power. Ewell published Comparing Methods for Confidence Intervals for Vaccine Efficacy in 1996, comparing eight methods. Since then, a number of other possible approaches and modifications of previous methods have been developed or become feasible. In this presentation, a review of methods for constructing exact and large sample intervals for vaccine efficacy is provided as a framework for comparison. Theoretical comparisons and simulation study are used to determine when and under what circumstances each method yields conservative, unbiased or anti-conservative lower limits of the confidence interval. Finally, it discusses the relative merits of the methods and provides suggestions on using these methods under different circumstances in terms of efficiency.

关键词： Confidence Interval Vaccine Efficacy Efficiency.

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Evaluation of Nutrition Surveys in Flood-affected Areas of Pakistan: Seeing the Unseen!

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IDS BULLETIN-INSTITUTE OF DEVELOPMENT STUDIES 2013年第3期44卷 10-20页

作者： Hossain, S. M. Moazzem Talat, Mah Boyd, Erin Chowdhury, Shamim Rafique Soofi, Sajid Bashir Hussain, Imtiaz Ahmed, Imran Salam, Rehana Abdus Bhutta, Zulfiqar A. Chief of Health and Nutrition in UNICEF Afghanistan having previously worked in UNICEF Pakistan Sri Lanka and the New York Headquarters. Certified Master Trainer with expertise in facilitation skills monitoring and programme management. Emergency Nutrition Specialist at the United Nations Children''s Fund (UNICEF) Headquarters with over ten years of experience in humanitarian response and policy related to emergency nutrition programming and data analysis. Has Been the Director General of the Bureau of Statistics (BOS) Planning and Development Department Government of Punjab Pakistan since 2007. Pediatrician and researcher. He is a Fellow of Pediatrics and has a long affiliation with the Department of Pediatrics and Child Health at the Aga Khan University Karachi where he is currently working as an Assistant Professor and Coordinator. Presently holds the position of Senior Social Scientist at the Aga Khan University Karachi. Working as Data Manager at the Department of Paediatrics Aga Khan University Karachi. Has been a Senior Instructor (Research) at the Aga Khan University Karachi since November 2012 and holds a master''s degree in Epidemiology and Biostatistics from the university. Professor and founding chair of the Division of Maternal and Child Health Aga Khan University Karachi

In 2010 Pakistan experienced the worst floods recorded in its history;millions of people were affected and thousands lost their lives. Nutrition assessment surveys led by UNICEF were conducted in flood-affected areas of Punjab and Sindh provinces to assess the nutrition status of children between 659 months while Aga Khan University (AKU) undertook a parallel assessment including micronutrient status in their project areas within Balochistan, Sindh and Punjab. Standardised Monitoring and Assessment of Relief and Transition (SMART) methodology was used. 881 children from Sindh, 1,143 from Punjab and 817 from AKU project areas were measured for anthropometry and their households were interviewed. The findings indicated that while immediate life-saving interventions were essential, there was also an urgent need to address chronic malnutrition. Through high-level dissemination of the survey results, treatment and prevention of malnutrition has become a priority for the provincial and federal government in Pakistan and for donors.

关键词： FLOODS NUTRITION surveys MALNUTRITION -- Treatment ANTHROPOMETRY PUNJAB (Pakistan) -- Environmental conditions

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Implementation and comparison of machine learning classifiers for information security risk analysis of a human resources department

Implementation and comparison of machine learning classifier...

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International Conference on Computer Information Systems and Industrial Management Applications

作者： Eminagaoglu, Mete Eren, Saban Department of Computer Programming Yasar University Izmir Turkey Department of Statistics Yasar University Izmir Turkey

ISBN: (纸本)9781424478170

The aim of this study is threefold. First, a qualitative information security risk survey is implemented in human resources department of a logistics company. Second, a machine learning risk classification and prediction model with proper data set is established from the results obtained in this survey. Third, several classifier algorithms are tested where their training and test performances are compared using error rates, ROC curves, Kappa statistics and F-measures. The results show that some classifier algorithms can be used to estimate specific human based information security risks within acceptable error rates. ©2010 IEEE.

关键词： Surveys

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The positive outcomes of information security awareness training in companies - A case study

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Information Security Technical Report 2009年第4期14卷 223-229页

作者： Eminaǧaoǧlu, Mete Uçar, Erdem Eren, Şaban Yaar University Department of Computer Programming Izmir Turkey Trakya University Department of Computer Engineering Edirne Turkey Yaar University Department of Statistics Izmir Turkey

One of the key factors in successful information security management is the effective compliance of security policies and proper integration of "people", "process" and "technology". When it comes to the issue of "people", this effectiveness can be achieved through several mechanisms, one of which is the security awareness training of employees. However, the outcomes should also be measured to see how successful and effective this training has been for the employees. In this study, an information security awareness project is implemented in a company both by training and by subsequent auditing of the effectiveness and success of this training (which focussed on password usage, password quality and compliance of employees with the password policies of the company). The project was conducted in a Turkish company with 2900 white-collar employees. Each employee took information security training including password usage. Also, there were several supporting awareness campaigns such as educational posters, animations and e-messages on the company Intranet, surveys and simple online quizzes. The project was carried out over a 12 month period and three password security strength audits were made during this period. The results were comparatively and statistically analysed. The results show us the effectiveness of the project and the impact of human awareness on the success of information security management programmes in companies. This study gives us some crucial results, facts and methods that can also be used as a guideline for further similar projects. © 2010 Elsevier Ltd. All rights reserved.

关键词： Personnel training

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