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1.
《民法典》侵权责任编对原有通知删除规则进行了科学修正,但事前保护缺位与事后救济程序失范的问题仍然存在。随着网络服务提供者完成角色转型和技术升级,其作为网络侵权风险的控制者和参与者,有必要且有能力承担未通知阶段的主动预防义务和已通知阶段的证明材料审查义务,以弥补著作权保护和用户利益保护的漏洞。双重注意义务应分别与网络服务提供者对侵权危险的预期和控制能力以及材料审查能力相适应。未通知阶段之注意义务以技术措施为主要履行方式,其注意标准的认定应综合考量技术水平、服务类型、内容介入程度、是否直接获取收益等要素,未尽该注意义务仅为过错认定的考量因素而非唯一标准,并不必然导致侵权责任。已通知阶段之注意义务仅限于对提交的证明材料进行形式审查和有限的实质审查,尽到此注意义务的,可以免于承担侵权责任。  相似文献   
2.
Abstract

The problem of testing equality of two multivariate normal covariance matrices is considered. Assuming that the incomplete data are of monotone pattern, a quantity similar to the Likelihood Ratio Test Statistic is proposed. A satisfactory approximation to the distribution of the quantity is derived. Hypothesis testing based on the approximate distribution is outlined. The merits of the test are investigated using Monte Carlo simulation. Monte Carlo studies indicate that the test is very satisfactory even for moderately small samples. The proposed methods are illustrated using an example.  相似文献   
3.
《Risk analysis》2018,38(9):1988-2009
Harbor seals in Iliamna Lake, Alaska, are a small, isolated population, and one of only two freshwater populations of harbor seals in the world, yet little is known about their abundance or risk for extinction. Bayesian hierarchical models were used to estimate abundance and trend of this population. Observational models were developed from aerial survey and harvest data, and they included effects for time of year and time of day on survey counts. Underlying models of abundance and trend were based on a Leslie matrix model that used prior information on vital rates from the literature. We developed three scenarios for variability in the priors and used them as part of a sensitivity analysis. The models were fitted using Markov chain Monte Carlo methods. The population production rate implied by the vital rate estimates was about 5% per year, very similar to the average annual harvest rate. After a period of growth in the 1980s, the population appears to be relatively stable at around 400 individuals. A population viability analysis assessing the risk of quasi‐extinction, defined as any reduction to 50 animals or below in the next 100 years, ranged from 1% to 3%, depending on the prior scenario. Although this is moderately low risk, it does not include genetic or catastrophic environmental events, which may have occurred to the population in the past, so our results should be applied cautiously.  相似文献   
4.
In most mid- and high-income countries, there have been significant demographic, structural, and cultural changes in the past decades. However, we know little about how these changes have shaped women's work patterns during a key life stage: the transition to motherhood. Using longitudinal data from Chile, covering over 30 years of employment histories and three periods of first births (1980–2010), I conduct sequence analysis to identify women's work-care trajectories during an eight-year period of the transition to motherhood. Over time, I find that continuous care work at home has declined, for which education plays a key role, while the chances of working continuously have not changed over time. Instead, I find an increasing trend of unsteady paths that combine paid work with either caretaking or unemployment. I discuss how these changes, as well as their association with education, have important implications for both gender and social inequality.  相似文献   
5.
Random effects regression mixture models are a way to classify longitudinal data (or trajectories) having possibly varying lengths. The mixture structure of the traditional random effects regression mixture model arises through the distribution of the random regression coefficients, which is assumed to be a mixture of multivariate normals. An extension of this standard model is presented that accounts for various levels of heterogeneity among the trajectories, depending on their assumed error structure. A standard likelihood ratio test is presented for testing this error structure assumption. Full details of an expectation-conditional maximization algorithm for maximum likelihood estimation are also presented. This model is used to analyze data from an infant habituation experiment, where it is desirable to assess whether infants comprise different populations in terms of their habituation time.  相似文献   
6.
Abstract

In this article we develop the minimax estimation approach of general linear models to the semiparametric linear models when the parameters are simultaneously constrained by an ellipsoid and linear restrictions. Combining sample information and prior constraints the minimax estimator is obtained and compared with partially least square estimator by theoretical and simulation methods.  相似文献   
7.
依据水杨酸、间苯二酚、对氨基苯甲酸三组分的比值光谱特征,以对氨基苯甲酸为干扰组分,选择241nm、278nm作为测定水杨酸的波长;以水杨酸作为干扰组分,选择214nm、240nm作为测定间苯二酚的波长;以间苯二酚作为干扰组分,选择222nm、279nm作为测定对氨基苯甲酸的波长.结果显示,水杨酸浓度在1~80mg/L,基本二酚浓度在0.8~40mg/L,对氨基苯甲酸浓度在0.4~40mg/L范围内具有良好的线性关系.本方法具有测定波长少,光谱分离能力强、计算简单、能在低档分光光度计上实现、易于推广等特点.  相似文献   
8.
Abstract

The mean estimators with ratio depend on multiple auxiliary variables and unknown parameters in a finite population setting. We propose a new generalized approach with matrices for modeling the mutivariate mean estimators with two auxiliary variables. Our approach brings naturally a graphical analysis for comparing mean estimators.  相似文献   
9.
金诗学唐的历程   总被引:1,自引:0,他引:1  
金代诗歌在受苏轼等宋代诗人的影响之外 ,也受到唐诗的浸润。本文依据金诗发展变化的自身情况 ,考察了金诗学唐的历程。文中将金诗学唐分为金初“借才异代”时期、“国朝文派”时期、金代后期等三个阶段 ,做了比较详细的论述 ,从一个方面展示了金诗发展的轨迹 ,揭示了金诗的某些重要特点 ,对于我们深入地认识金诗是有裨益的  相似文献   
10.
This report evaluates the extent of perceived and enacted HIV/AIDS-related stigma in a rural setting in Zambia. Stigmatisation is abundant, ranging from subtle actions to the most extreme degradation, rejection and abandonment. Women with HIV and pregnant women assumed to be HIV positive are repeatedly subjected to extensive forms of stigma, particularly once they become sick or if their child dies. Despite increasing access to prevention of mother to child transmission initiatives, including anti-retroviral drugs, the perceived disincentives of HIV testing, particularly for women, largely outweigh the potential gains from available treatments. HIV/AIDS related stigma drives the epidemic underground and is one of the main reasons that people do not wish to know their HIV status. Unless efforts to reduce stigma are, as one peer educator put it, “written in large letters in any HIV/AIDS campaign rather than small”, stigma will remain a major barrier to curbing the HIV/AIDS pandemic.  相似文献   
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