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1.
利用美国M IL-STD-822B标准的原理和方法构建了出口食品农产品检验检疫风险评价矩阵,首次定义了检验检疫风险事故是不合格产品引起的国内外不良反应,并制定了风险事故后果的严重等级划分标准,确立了以一年内发生风险事故的频次作为风险事故发生概率的原则;同时依据欧盟2002/63/EC指令对风险评价结果制定了以连续459批为一个监控周期的抽样方案。根据风险评价体系,将出口食品农产品检验检疫风险设置为5个风险等级:HHH、HH、H、M和L,依据监控抽样的检测结果可以对具体出口企业和产品进行风险等级加严或放宽的动态调节。  相似文献   
2.
本文分析了日本福岛第一核电站核泄漏的情况和放射性物质可能扩散到我国的途径,并对日本福岛核泄漏事件对我国的影响进行了风险评估。最后结论为:根据目前的情况,日本福岛核泄漏事件不会危害我国公民的健康。  相似文献   
3.
本文根据新古典贸易模型中的贸易所得的理论定义,对测算源于比较优势的贸易所得的基本方法及其理论基础进行了回顾和分析,在此基础上利用进出口额的现值与贸易所得的估算值之间的格兰杰逻辑关系,对中国源于比较优势的贸易所得进行了测算。本文的测算结果表明,中国源于比较优势的贸易所得的最大估算值约为GDP的5%。从比较的角度考察,这一结论的政策含义是,主要依赖劳动力资源或不可再生自然资源比较优势的贸易模式已不具备可持续发展性,建立基于动态比较优势的对外贸易战略应成为包括中国在内的发展中国家的贸易政策选择。  相似文献   
4.
随着经济和社会的快速发展,人们越来越关注自然资源的价值和生态环境的效益。评估森林生态资产已经成为学术界研究的焦点问题。通过比较其他研究者的成果,总结出生态资产评估现存的三个视角,并分析了各自的优缺点。按照寒温带针叶林、温带落叶阔叶林、针阔混交林等不同林分,对伊春林区森林的涵养水源价值、固定C02和释放02价值、保育土壤价值、营养物质循环和养分储藏、净化大气环境、生物多样性保护、森林景观资源等7种生态资产形式在三种视角下做出评估,并比较三种视角下的差异,在此基础上提出了生态资产运营途径,旨在为伊春林区森林可持续发展政策的制定提供参考依据,对该区域森林资源保护和利用具有重要的意义。  相似文献   
5.
I. Caas  E. Ayuga  F. Ayuga 《Land use policy》2009,26(4):1173-1181
The purpose of this paper is to validate a model for predicting the public's preference for a landscape using simple statistical techniques. The model assigns numerical values to 42 landscape variables grouped into physical, aesthetic and psychological attributes. The landscape value is obtained using an additive value function. The results of the model on certain landscapes are compared with the preference expressed by the public in a survey of 183 people.The homogeneity of the survey responses was checked in each photograph. It was determined that means and standard deviations of the scores represent the true preference.A strong positive association was observed between preference and certain landscape attributes such as expression, soil use or colour. A marked negative association was detected with respect to landscape alterations.A linear regression was carried out to analyse the predictive capacity of the model. The independent variable was the global score assigned by the model to each photograph and the dependant variable was the mean of the scores assigned by the survey respondents. The high level of correlation obtained indicates that the model is a good predictor of the public's preferences in relation to the set of photographs shown in the survey.To complete the analysis of the model as a preference predictor, a multiple linear regression was carried out between the mean score obtained in the survey and the model elements. Attributes and variables that have the greatest influence on pubic preference were detected.  相似文献   
6.
本文首先介绍了美国财产税在美国地方财政中的重要地位及财产税的基本税制构成,进而对美国财产税的估税周期与估税方法进行了详细分析,以期为我国今后可能开征的物业税税制设计提供参考。  相似文献   
7.
This study summarizes the main conclusions from a systematic review of the empirical literature regarding the impact on firms of the use of knowledge external sources (universities, research institutes and knowledge intensive business services). With the aim to organize the literature, we classify the different works according to the research question addressed: (i) which firms use knowledge external sources?; (ii) Do firms using knowledge external sources achieve better results?; And (iii) which firms benefit the most from using knowledge external sources? Stylized facts are that larger, more R&D intensive and high tech firms are more likely to use knowledge external sources and that use of knowledge external sources is associated to firms higher technical results. Less attention has been paid to the third question and evidence is not conclusive. Several recommendations for future research emerge. First, to take in greater consideration methodological issues so that potential biases in the results caused by sample selection and endogeneity are handled properly. Second, to pay more attention to heterogeneous outcomes. Third, to use continuous indicators of depth and breadth of links allowing for non‐linear relationships and fourth, to extend evidence for developing countries and service industries.  相似文献   
8.
基于价值评价的外包决策模型研究   总被引:3,自引:0,他引:3  
业务外包已经成为企业适应复杂的竞争环境的必然选择,基于价值评价的外包决策模型通过经济增加值和战略价值评价形成四种可能的结果,根据不同的评价结果企业可以进行是否外包的战略决策。  相似文献   
9.
Background: Biologic treatments have enhanced the treatment outcomes of patients with active ankylosing spondylitis (AS). Until recently, TNF-alpha-inhibitors have been the only biologics approved for the treatment of active AS. The objective of this study was to assess the potential financial impact of the first non-TNF-alpha biologic secukinumab (fully human IL-17A-inhibitor) vs adalimumab (TNF-alpha-inhibitor) in the treatment of AS in Finland.

Materials and methods: In this model-based budget impact analysis, patients were treated either with secukinumab (150?mg) or adalimumab (40?mg). The number of patients and market share of different biologics were based on national reimbursement registry data. Adalimumab was the most commonly used biologic treatment for AS, and in the base case analysis all adalimumab patients are assumed to switch to secukinumab. Response rates were based on a matching-adjusted indirect comparison between secukinumab and adalimumab. Patients not achieving response were switched to another biologic treatment.

Results: Treating AS patients with secukinumab instead of adalimumab leads to potential savings of 18.2 million euros within a 5-year time period. The total costs within the follow-up time were 59.5 million euros and 77.7 million euros with and without secukinumab, respectively. According to sensitivity analyses, a higher adoption rate of secukinumab corresponds to higher potential savings.

Conclusions: Secukinumab is a cost-saving treatment option compared with adalimumab in the treatment of AS in Finland. More patients could be treated with a biologic by allocating resources more efficiently.  相似文献   
10.
Climate change is an inevitable trend,which challenges security of water resources in China,especially in cities.Assessing vulnerability of water resource to climate change in cities has important role for policy makers. The paper constructs a vulnerability function,including exposure,sensitivity and adaptive capacity,according to the vulnerability concept proposed by IPCC,establishes an assessment indicators system of water resources to climate change in cities,and analyzes vulnerability features of Chinese cites based on 655 cities'data in 2006.The vulnerability assessment results show that there are distinctive differences among all the cities,between east,central and west cities,between ordinary,big and mega cities,while there is no statistical significant difference between north and south cities.Based on the research,the paper suggests that strategic emphasis should focus on the central cities and ordinary cities  相似文献   
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