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31.
For decades renewable energy has remained a “blind spot” within the sphere of international energy governance. The existing institutional network is highly fragmented, resulting in a myriad of international organizations, which all claim to deal with energy issues, yet do not focus on renewables on a global scale. Since 2009, IRENA, the International Renewable Energy Agency, seeks to fill up this vacuum, thereby creating a new (and maybe more Southern-led) political arena for governing renewable energy issues. This article focuses on IRENA’s role as a changemaker in the sphere of global energy governance by investigating IRENA’s governance practices and contributions to knowledge production. 相似文献
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33.
Grün B Hornik K 《Journal of the Royal Statistical Society. Series C, Applied statistics》2012,61(2):201-218
The measurement of human immunodeficiency virus ribonucleic acid levels over time leads to censored longitudinal data. Suitable models for dynamic modelling of these levels need to take this data characteristic into account. If groups of patients with different developments of the levels over time are suspected the model class of finite mixtures of mixed effects models with censored data is required. We describe the model specification and derive the estimation with a suitable expectation-maximization algorithm. We propose a convenient implementation using closed form formulae for the expected mean and variance of the truncated multivariate distribution. Only efficient evaluation of the cumulative multivariate normal distribution function is required. Model selection as well as methods for inference are discussed. The application is demonstrated on the clinical trial ACTG 315 data. 相似文献
34.
Attribution theory remains popular in the social sciences and often informs education studies. However, attributional style questionnaires tend to reflect the context-dependent character of the theory and existing measures have been found to have poor psychometric properties. Clearly, both issues need to be carefully considered by researchers prior to them applying any scales that incorporate attributional dimensions. Here we report on the development of a reliable and valid measure that applies an attributional style within the context of citizenship. Two separate studies were conducted to inform the development of the Citizenship Attributional Style Questionnaire (CASQ). The factor loadings of eight positive and eight negative events for the internality and stability dimensions were found to range between .41 and .75. The Cronbach’s alpha reliability of positive and negative events were found to be .79 and .74, respectively. While CASQ is seen to be a reliable and valid measure, the results also indicate broader psychometric properties than many of the instruments currently used in studies with an attributional approach. 相似文献
35.
İlknur Aykurt Karlıbel Seyhan Dülger Meliha Kasapoğlu Aksoy Muhammet Güzelsoy Ali Rıza Türkoğlu Lale Altan 《The aging male》2019,22(2):109-115
Objective: This study aims to investigate the effect of smoking on sexual functions in AS patients.Patients and methods: A total of 67 male AS patients with a median age of 34 years (range: 18–57) reporting sexual activity at least for the past 4 weeks period were included. Patients were divided into smokers (Group 1, n?=?47) and non-smokers (Group 2, n?=?20). Fagerström test for nicotine dependence, smoking history, exhaled carbon monoxide test were recorded for smoking AS patients. Visual analogue scale (VAS), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Metrology Index (BASMI), Bath Ankylosing Spondylitis Functional Index (BASFI), Ankylosing Spondylitis Quality of Life (ASQoL), International Index of Erectile Function (IIEF), Beck Depression Inventory (BDI) were filled for both groups.Results: There was no significant difference between smokers and non-smokers in all evaluation parameters. BASMI scores were significantly lower in the mild dependency subgroup as compared to those with moderate or severe dependency (p?=?.005 and p?=?.007, respectively). Total IIEF score and IIEF categories correlated significantly with BASDAI, BASFI, BASMI, ASQoL, pain, fatigue, and cumulative smoking. BDI showed an inverse correlation with the IIEF score and IIEF category (p?.001 r?=?–0.520, p?.001 r?=?–0.508, respectively).Conclusions: Sexual function in AS patients is associated with the pain, fatigue, disease activity, functional status, quality of life, depression as well as the cumulative exposure to smoking, and that sexual functions tend to decline with increasing degree of cigarette dependency. 相似文献
36.
Many optimisation problems arise in managing the Blood Donation (BD) supply chain. Most of them have been addressed in the literature, while other problems, e.g. donation scheduling, have not been sufficiently addressed so far. However, blood collection from donors may have a disruptive impact on the entire BD supply chain if not properly managed. For example, scheduling donation appointments based on some system metrics may improve the flow of blood units through the BD supply chain and increase the quality of service perceived by donors. In this short communication, we present the donation scheduling problem and highlight the lack of work in the literature that deals with this problem. Then, we analyse the impact of an unbalanced flow of blood units on the BD system and the benefits that may derive from a suitable appointment scheduling. Finally, we propose suggestions for future research in BD collection scheduling that may improve the BD process. 相似文献
37.
38.
Prior information is often incorporated informally when planning a clinical trial. Here, we present an approach on how to incorporate prior information, such as data from historical clinical trials, into the nuisance parameter–based sample size re‐estimation in a design with an internal pilot study. We focus on trials with continuous endpoints in which the outcome variance is the nuisance parameter. For planning and analyzing the trial, frequentist methods are considered. Moreover, the external information on the variance is summarized by the Bayesian meta‐analytic‐predictive approach. To incorporate external information into the sample size re‐estimation, we propose to update the meta‐analytic‐predictive prior based on the results of the internal pilot study and to re‐estimate the sample size using an estimator from the posterior. By means of a simulation study, we compare the operating characteristics such as power and sample size distribution of the proposed procedure with the traditional sample size re‐estimation approach that uses the pooled variance estimator. The simulation study shows that, if no prior‐data conflict is present, incorporating external information into the sample size re‐estimation improves the operating characteristics compared to the traditional approach. In the case of a prior‐data conflict, that is, when the variance of the ongoing clinical trial is unequal to the prior location, the performance of the traditional sample size re‐estimation procedure is in general superior, even when the prior information is robustified. When considering to include prior information in sample size re‐estimation, the potential gains should be balanced against the risks. 相似文献
39.
Demographic ageing is a challenge for many countries. Even though Turkey has a relatively younger demographic composition, the proportion of the older people (65+) within the population is rapidly increasing. Within this framework, older people are becoming more important clients for both social work students and social workers in Turkey. This study aims to reveal the attitudes of social work students towards older people and determine the various factors that affect their views on older persons. In the scope of the project, Kogan's Attitude Towards Old People Scale was applied to 419 social work undergraduate students at a university located in Central Anatolia. The findings showed that social work students scored a mean of 130.96 and they generally had positive attitudes towards older people. The correlation between year of study, gender and age was not statistically significant. However, having lived mostly in urban areas was positively correlated with the mean Kogan scores and this finding was found to be statistically significant. Exposure to personal contact with older people at both the personal and professional levels was influential in shaping attitudes about the older people. 相似文献
40.
Cord A. Müller 《Journal of applied statistics》2019,46(13):2338-2356
ABSTRACTAcceptance sampling plans offered by ISO 2859-1 are far from optimal under the conditions for statistical verification in modules F and F1 as prescribed by Annex II of the Measuring Instruments Directive (MID) 2014/32/EU, resulting in sample sizes that are larger than necessary. An optimised single-sampling scheme is derived, both for large lots using the binomial distribution and for finite-sized lots using the exact hypergeometric distribution, resulting in smaller sample sizes that are economically more efficient while offering the full statistical protection required by the MID. 相似文献