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关键词： 渔船检验   执法监督   事故发生   渔船安全   基础   安全隐患   安全管理   安全技术  

摘要： 开展全国渔船检验执法监督三大行动，旨在摸清全国渔船家底，消除安全隐患，解决渔船安全管理中多年存在的突出问题，提升我国渔船安全技术水平。

关键词： 组织文化   员工导向   结果导向   组织承诺   职业成长  

摘要： 以组织文化为自变量,组织承诺为因变量,员工职业成长为中介变量,讨论组织文化对组织承诺的影响机制。通过对385份有效样本进行统计分析,得出结论:员工导向文化正向影响组织承诺,结果导向文化负向影响组织承诺;员工导向文化正向影响职业成长,结果文化导向负向影响职业成长;职业成长在组织文化对组织承诺的影响中起不完全中介作用,职业成长的子维度在组织文化和组织承诺子维度间的中介作用存在影响差异。

关键词： Mobile explosive identification   Homemade explosives   IED   Primary explosives   Propellants   TNT  

摘要： To test explosive properties of substances, the strong exothermal reaction of an explosive after ignition can be used. Monitoring the emitted visible or infrared radiation by photodiodes and the change in pressure by a transducer in a closed system offers a low cost and mobile explosive identification device. The explosives investigated were hexamethylene triperoxide diamine, pentaerythritol tetranitrate, ammonium gelignite, ammonium nitrate fuel oil, cyclotrimethylene trinitramine, cyclotetramethylene tetranitramine, black powder, nitrocellulose, trinitrophenylmethylnitramine, gun propellant, triacetone triperoxide and trinitrotoluene. It has been shown, that the fast thermal activation of single-digit mg samples yields reproducible results for primary explosives, propellants, and trinitrotoluene. An analysis of the volatile reaction products with commercial semi-conductor gas sensors enables a differentiation between nitrate- and peroxide-based explosives and non-explosives. (C) 2015 Elsevier B.V. All rights reserved.

关键词： experts   hypothesis testing   Chernoff-Stein lemma   Neyman-Pearson lemma   naive Bayes   measure concentration  

摘要： We revisit, from a statistical learning perspective, the classical decision-theoretic problem of weighted expert voting. In particular, we examine the consistency (both asymptotic and finitary) of the optimal Naive Bayes weighted majority and related rules. In the case of known expert competence levels, we give sharp error estimates for the optimal rule. We derive optimality results for our estimates and also establish some structural characterizations. When the competence levels are unknown, they must be empirically estimated. We provide frequentist and Bayesian analyses for this situation. Some of our proof techniques are non-standard and may be of independent interest. Several challenging open problems are posed, and experimental results are provided to illustrate the theory.

关键词： BRCA1   Breast cancer   Classification   Copy number aberration profiles  

摘要： Breast cancers with BRCA1 germline mutation have a characteristic DNA copy number (CN) pattern. We developed a test that assigns CN profiles to be 'BRCA1-like' or 'non-BRCA1-like', which refers to resembling a BRCA1-mutated tumor or resembling a tumor without a BRCA1 mutation, respectively. Approximately one third of the BRCA1-like breast cancers have a BRCA1 mutation, one third has hypermethylation of the BRCA1 promoter and one third has an unknown reason for being BRCA1-like. This classification is indicative of patients' response to high dose alkylating and platinum containing chemotherapy regimens, which targets the inability of BRCA1 deficient cells to repair DNA double strand breaks. We investigated whether this classification can be reliably obtained with next generation sequencing and copy number platforms other than the bacterial artificial chromosome (BAC) array Comparative Genomic Hybridization (aCGH) on which it was originally developed. We investigated samples from 230 breast cancer patients for which a CN profile had been generated on two to five platforms, comprising low coverage CN sequencing, CN extraction from targeted sequencing panels (CopywriteR), Affymetrix SNP6.0, 135K/720K oligonucleotide aCGH, Affymetrix Oncoscan FFPE (MIP) technology, 3K BAC and 32K BAC aCGH. Pairwise comparison of genomic position-mapped profiles from the original aCGH platform and other platforms revealed concordance. For most cases, biological differences between samples exceeded the differences between platforms within one sample. We observed the same classification across different platforms in over 80% of the patients and kappa values of at least 0.36. Differential classification could be attributed to CN profiles that were not strongly associated to one class. In conclusion, we have shown that the genomic regions that define our BRCA1-like classifier are robustly measured by different CN profiling technologies, providing the possibility to retro- and prospectively in

关键词： Airline merger   Mergers & acquisitions   Synergies   Cost synergies   Revenue synergies  

摘要： Deregulation, privatization and shifting demand patterns in the airline industry, combined with the emergence of low-cost airlines and rising fuel prices have increased the competitive pressure on legacy airlines. Since alliances do not deliver sufficient benefits to counterbalance these trends, many airlines have engaged in mergers to seek for additional cost and revenue synergies. An extent body of literature investigates the synergy potential in mergers and alliances, but there is no study on how synergies differ among mergers and what potential influence factors cause these differences. This paper aims at explaining differences in synergy estimates and realized synergies in recent airline mergers and places a special focus on geographical influence factors. The research methodology uses a comparative case study comprising six large airline mergers between 2003 and 2012 from Europe, North America and Latin America. After analyzing the cases individually, the pre-merger situation of the merging airlines, the synergy estimates and the realized synergies of the cases were compared. The results show considerable geographical differences in pre-merger cost structures, synergy estimates, and synergy realization. The European mergers present lower synergy estimates but also lower integration costs than mergers in the Americas. Whereas European airlines estimate cost synergies higher than revenue synergies, both North and Latin American airlines expect more revenue synergies than cost synergies from airline mergers. Only one merger showed superior post-merger profitability which indicates that the achieved synergies in the broad majority of the cases are insignificant. (C) 2015 Elsevier Ltd. All rights reserved.

关键词： Directed acyclic graph support vector machines   Benthic macroinvertebrates   Machine learning   Classification  

摘要： Freshwater areas are an evanescent resource in the globe and, hence, the water quality assessment and examination of human induced changes on aquatic ecosystems are important. Benthic macroinvertebrates are excellent indicators of the state of freshwater area due to their intermediate life cycle and their ability to react changes in an aquatic ecosystem. However, identifying the benthic macroinvertebrates is a slow and expensive task when the process is human-made. Thus, we have an excellent opportunity to save resources by using sophisticated machine learning and pattern recognition methods. In this research we applied Directed Acyclic Graph Support Vector Machine (DAGSVM) and six other baseline methods in automated benthic macroinvertebrate classification. We performed wide experimental tests with six different feature sets where one was chosen by Scatter method. Furthermore, in the case of DAGSVM we tested every feature set with seven kernel functions. Experimental results showed that Scatter method is a good feature selection algorithm and we obtained above 80 % accuracy in classifications which is a very good result for such a challenging classification task. From all tested classification methods DAGSVM showed to be the best alternative for this classification task.

关键词： Spam   Social Networks   Preprocessing   KNN   R Package   Feature Extraction  

摘要： Spam is one of the problems which are faced on Social Networking Websites. Everyone today uses the internet very much and hence, everyone is familiar with the spam too. Spam is nothing but the mails or more appropriately it is defined as junk mails which create hindrance in doing the work. Various techniques like Decision Tree, Na?ve Bayesian etc are available to deal with this problem. Here, in this paper a spam detection system has been introduced involving the use of the Clustered KNN approach because of which great accuracy has been achieved and that too in no time.

关键词： Logistic regression   Classification   Oil analysis   Mining trucks   Machine health   Neural networks   Support vector machine   Receiver operating characteristic curve  

摘要： The era of big data has resulted in an explosion of condition monitoring information. The result is an increasing motivation to automate the costly and time consuming human elements involved in the classification of machine health. When working with industry it is important to build an understanding and hence some trust in the classification scheme for those who use the analysis to initiate maintenance tasks. Typically "black box" approaches such as artificial neural networks (ANN) and support vector machines (SVM) can be difficult to provide ease of interpretability. In contrast, this paper argues that logistic regression offers easy interpretability to industry experts, providing insight to the drivers of the human classification process and to the ramifications of potential misclassification. Of course, accuracy is of foremost importance in any automated classification scheme, so we also provide a comparative study based on predictive performance of logistic regression, ANN and SVM. A real world oil analysis data set from engines on mining trucks is presented and using cross-validation we demonstrate that logistic regression out-performs the ANN and SVM approaches in terms of prediction for healthy/not healthy engines. (C) 2015 Elsevier Ltd. All rights reserved.

关键词： binary data   double sampling   identifiability   misclassification   contingency table  

摘要： In this article, we construct two likelihood-based confidence intervals (CIs) for a binomial proportion parameter using a double-sampling scheme with misclassified binary data. We utilize an easy-to-implement closed-form algorithm to obtain maximum likelihood estimators of the model parameters by maximizing the full-likelihood function. The two CIs are a naive Wald interval and a modified Wald interval. Using simulations, we assess and compare the coverage probabilities and average widths of our two CIs. Finally, we conclude that the modified Wald interval, unlike the naive Wald interval, produces close-to-nominal CIs under various simulations and, thus, is preferred in practice. Utilizing the expressions derived, we also illustrate our two CIs for a binomial proportion parameter using real-data example.