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关键词： Cloud computing   Data privacy   Data splitting   Nominal data  

摘要： Outsourcing data storage and computation to the cloud is appealing due to the cost savings it entails. However, when the data to be outsourced contain private information, appropriate protection mechanisms should be implemented by the data controller. Data splitting, which consists of fragmenting the data and storing them in separate clouds for the sake of privacy preservation, is an interesting alternative to encryption in terms of flexibility and efficiency. However, multivariate analyses on data split among various clouds are challenging, and they are even harder when data are nominal categorical (i.e., textual, non-ordinal), because the standard arithmetic operators cannot be used. In this article, we tackle the problem of outsourcing multivariate analyses on nominal data split over several honest-but-curious clouds. Specifically, we propose several secure protocols to outsource to multiple clouds the computation of a variety of multivariate analyses on nominal categorical data (frequency-based and semantic-based). Our protocols have been designed to outsource as much workload as possible to the clouds, in order to retain the cost-saving benefits of cloud computing while ensuring that the outsourced stay split and hence privacy-protected versus the clouds. The experiments we report on the Amazon cloud service show that by using our protocols the controller can save nearly all the runtime because it can integrate partial results received from the clouds with very little computation.

关键词： Sap flow   Rainfall category   Inter-specific variation   Xerophytic shrub   Drylands  

摘要： Global climate change is likely to change the timing, frequency and magnitude of precipitation events, studying the response of sap flow (SF) of plants to rainfall events is thus important for understanding the response of ecosystems to global climate change. Here, we conducted a comprehensive study on the SF, rainfall events, meteorological factors and soil water content (SWC) for two typical xerophytic shrub stands (Caragana korshinskii and Salix psammophila) on the Loess Plateau of China for two rainy seasons (June-September) in 2015 and 2016. The rainfall events were classified into three rainfall categories using the K-means clustering based on the rainfall amount (RA), rainfall duration (RD) and rainfall intensity (RI) (category I: lowest mean RA, RD and RI, category II: moderate mean RA, RI and highest mean RD and category III: highest mean RA, RI and moderate mean RD). The results showed that the response of SF at both C. korshinskii and S. psammophila stands to rainfall events differed within the three categories. The occurrence of rainfall events significantly decreased daily SF of C. korshinskii in three rainfall categories, whereas the daily SF of S. psammophila is more strongly influenced by rainfall category II. Maximum decreases in daily SF between the pre-rainfall and the rainfall weather condition of the two stands both occurred in rainfall category II. Daily rainfall SF at both stands was strongly correlated with daily SR, RH and VPD, regardless of the rainfall categories. Diurnal variation of hourly SF at both stands also differed among the days with similar RA and RD in the same rainfall category. It can be inferred that SF of C. korshinskii is more susceptible to rainfall events than S. psammophila. Rainfall characteristics (RA, RD and RI) and rainfall distribution should be fully considered when assessing the response of SF of shrubs to rainfall events.

关键词： Human reliability analysis (HRA)   organizational factors   probabilistic risk assessment (PRA)   probabilistic safety assessment (PSA)  

摘要： This article presents a discourse on the incorporation of organizational factors into probabilistic risk assessment (PRA)/probabilistic safety assessment (PSA), a topic of debate since the 1980s that has spurred discussions among industry, regulatory agencies, and the research community. The main contributions of this article include (1) identifying the four key open questions associated with this topic; (2) framing ongoing debates by considering differing perspectives around each question; (3) offering a categorical review of existing studies on this topic to justify the selection of each question and to analyze the challenges related to each perspective; and (4) highlighting the directions of research required to reach a final resolution for each question. The four key questions are: (I) How significant is the contribution of organizational factors to accidents and incidents? (II) How critical, with respect to improving risk assessment, is the explicit incorporation of organizational factors into PRA? (III) What theoretical bases are needed for explicit incorporation of organizational factors into PRA? (IV) What methodological bases are needed for the explicit incorporation of organizational factors into PRA? Questions I and II mainly analyze PRA literature from the nuclear domain. For Questions III and IV, a broader review and categorization is conducted of those existing cross‐disciplinary studies that have evaluated the effects of organizational factors on safety (not solely PRA‐based) to shed more light on future research needs. [ABSTRACT FROM AUTHOR]

关键词： Tame module category   Cluster category   Infinite radical   AR quiver  

摘要： We give a geometric realization of the module category of a hereditary algebra of type (A) over tilde. We work with oriented arcs to define a translation quiver isomorphic to the AuslanderReiten quiver of the module category of type (A) over tilde. To get a description of the module category, we introduce long moves between arcs. These allow us to include the infinite radical in the geometric description. Finally, our results can also be used to describe the corresponding cluster categories by taking unoriented arcs instead.

关键词： breast cancer   Breast Imaging-Reporting and Data System   breast density   risk factors   heterogeneous effect  

摘要： We evaluated the heterogeneity of the effect of known risk factors on breast cancer development based on breast density by using the Breast Imaging-Reporting and Data System (BI-RADS). In total, 4,898,880 women, aged 40-74 years, who participated in the national breast cancer screening program in 2009-2010 were followed up to December 2018. Increased age showed a heterogeneous association with breast cancer (1-year hazard ratio (HR) = 0.92, 1.00 (reference), 1.03, and 1.03 in women with BI-RADS density category 1, 2, 3, and 4, respectively;P-heterogeneity < 0.001). More advanced age at menopause increased breast cancer risk in all BI-RADS categories. This was more prominent in women with BI-RADS density category 1 but less prominent in women in other BI-RADS categories (P-heterogeneity = 0.009). In postmenopausal women, a family history of breast cancer, body mass index >= 25 kg/m(2), and smoking showed a heterogeneous association with breast cancer across all BI-RADS categories. Other risk factors including age at menarche, menopause, hormone replacement therapy after menopause, oral contraceptive use, and alcohol consumption did not show a heterogeneous association with breast cancer across the BI-RADS categories. Several known risk factors of breast cancer had a heterogeneous effect on breast cancer development across breast density categories, especially in postmenopausal women.

关键词： morphology   linguistic typology   verbal agreement   morphotactics   linguistic complexity   language evolution  

摘要： Recent research has revealed several languages (e.g. Chintang, Raramuri, Tagalog, Murrinh-patha) that challenge the general expectation of strict sequential ordering in morphological structure. However, it has remained unclear whether these languages exhibit random placement of affixes or whether there are some underlying probabilistic principles that predict their placement. Here we address this question for verbal agreement markers and hypothesize a probabilistic universal of category clustering, with two effects: (i) markers in paradigmatic opposition tend to be placed in the same morphological position ('paradigmatic alignment';Crysmann & Bonami 2016);(ii) morphological positions tend to be categorically uniform ('featural coherence';Stump 2001). We first show in a corpus study that category clustering drives the distribution of agreement prefixes in speakers' production of Chintang, a language where prefix placement is not constrained by any categorical rules of sequential ordering. We then show in a typological study that the same principle also shapes the evolution of morphological structure: although exceptions are attested, paradigms are much more likely to obey rather than to violate the principle. Category clustering is therefore a good candidate for a universal force shaping the structure and use of language, potentially due to benefits in processing and learning.

关键词： Engaging employees   Creative potential   Innovation  

摘要： Dynamically changing environment and the coming fourth industrial revolution represent a great challenge for businesses not only in Slovakia;and increasing companies ' innovation potential is the way how such challenges can be successfully dealt with. The internal potential of a company is most significantly affected by the potential and commitment of its employees, which can be directly influenced by the individual activities of human resource management. The paper aims at analysing the focus of Slovak organisations on the activities associated with the commitment of all employees in innovation processes, and at identifying the overall change in their orientation on this issue in time. A questionnaire survey conducted between 2014 and 2018 was used to achieve the purpose of the article, which was followed by the statistical evaluation of the research hypotheses, and the evaluation of the overall change of the examined attributes using the indices of change. The obtained results showed a positive trend as to the level of the commitment of all employees in innovation processes;however the uncovered present state was not considered to be sufficient.

关键词： Morphisms determined by objects   Krull-Schmidt categories   Almost split sequences   Strongly locally finite quivers  

摘要： We study the existence and uniqueness of minimal right determiners in various categories. Particularly in a Hom-finite hereditary abelian category with enough projectives, we prove that the Auslander-Reiten-Smalo-Ringel formula of the minimal right determiner still holds. As an application, we give a formula of minimal right determiners in the category of finitely presented representations of strongly locally finite quivers.

关键词： Epidemiology   Risk factors  

摘要： Background Previous studies have shown that occupants with obesity are at a greater risk of fatality and serious injury than other occupants in motor vehicle crashes. Objective To provide a more complete description of the most frequent injuries and the most frequently injured body regions for occupants with obesity. Methods Sampled cases (n = 13,470) representing ~4.7 million adult occupants involved in frontal crashes (between 2000 and 2015) were selected from the U.S. National Automotive Sampling System-Crashworthiness Data System database. A retrospective cohort study was performed to study the effect of BMI on the risk of injury to different body regions and to identify the most frequent injuries to occupants with different BMIs. Lastly, in-depth crash analysis cases from the U.S. Crash Injury Research and Engineering Network (CIREN) database were studied to elucidate the source of the most common injuries to occupants with obesity. Results Occupants with obesity experienced a higher risk of upper extremity (4.79 vs 2.92%), lower extremity (8.37 vs 3.23%), and spine (1.53 vs 1.09%) injuries than other occupants. After adjusting for other variables, the risks of spinal, thoracic, and extremities injuries were found to be affected by the BMI class. Seven out of the ten most common injuries sustained by occupants with obesity were lower extremity injuries, and talus fractures were the most common overall. Direct loading through the plantar surface of the foot by the vehicle toe pan was found to be a likely cause of many of those injuries based on CIREN cases. Conclusions The injuries of occupants with obesity are different than other occupants which can be attributed to their different interaction with the seat belt and vehicle interior. The findings of this study should be considered for designing restraint systems to protect occupants with obesity in car crashes.

关键词： REACH   Exposure modeling   Environmental release category   SpERC   Pesticide  

摘要： The European Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) regulation requires that quantitative environmental risk assessment is carried out for hazardous substances used as coformulants in plant protection products (PPPs), if registered above 10 t/y. The European Crop Protection Association (ECPA) has developed generic exposure scenarios and specific environmental release categories (SpERCs) to support these risk assessments. The SpERCs offer refinements to the default release factors defined in environmental release categories (ERCs) and are intended to be used with nested multimedia mass balance models as part of the assessment of regional predicted environmental concentrations. Based on the application method of PPPs, 2 scenarios were defined for which SpERCs were developed: 1) spraying of PPPs and 2) direct application of granular products or treated seeds to soil. The SpERC for spray applications includes release factors to air and soil that depend on the vapor pressure of the coformulant. Calculations are presented to support the subSpERCs describing the transition from nonvolatile to volatile behavior. The most recent version of the spray application SpERC defines a release factor for surface water and more conservative release factors to soil compared with previous versions. Use of the ECPA SpERCs allows the coformulant emissions from PPPs to be fully accounted for in the regional-scale environmental risk assessment for a given substance, along with all other sources of emissions. Qualitative and quantitative justification for the ECPA-derived SpERCs is presented and serves as the background documentation to the online European Chemicals Agency (ECHA) SpERC factsheets. The approach developed here whereby regional-scale SpERCs are used in combination with a customized local-scale exposure model is potentially applicable for other sectors that are required to conduct exposure assessments outside the scope of the standard enviro