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331.
While there are many studies of self-regulation, they have not yet systematically analyzed the very process by which rules are developed and implemented. This article treats self-regulation as a process with sufficient autonomy and functional coherence to display identifiable stages, each of which deserves independent attention in turn. It draws from the literature on the stages of public policy processes and uses this as a template to identify and analyze the unique properties of private rule-making, while acknowledging the criticisms that have been made of excessive determinism and simplicity in some applications of the general idea of stages. The article shows that our understanding of self-regulation is significantly advanced by examining it as a process with stages but it emphasizes that the different stages of the self-regulatory policy process (agenda-setting, problem identification, decision, implementation and evaluation) are criss-crossed in numerous and interesting ways. It also shows that private rule-making often seeks to solve societal problems in domestic and international settings and is an important alternative to public regulation but self-regulation is rarely completely de-coupled from public authority. Instead, public authority is activated to solidify self-regulatory arrangements across the different stages of the policy process.  相似文献   
332.
Short tandem repeat (STR) analysis is a valuable tool in identifying the source of biological stains, particularly from the investigation of sexual assault crimes. Difficulties in analysis arise primarily in the interpretation of mixed genotypes when cell separation of the sexual assailant's sperm from the victim's cells is incomplete. The forensic community continues to seek improvements in cell separation methods from mixtures for DNA typing. The feasibility of applying laser microdissection (LMD) technology to precisely separate sexual assault cell mixtures by visual inspection coupled with laser dissection was assessed through three experiments. First, various histological stains were evaluated for use with LMD and DNA analysis. Second, different DNA isolation methods were evaluated on LMD-collected cells. Finally, STR analysis was performed on LMD-separated sperm cells from mixtures of semen and female buccal epithelial cells. The results indicated (a) hematoxylin/eosin staining performed best in its ability to differentiate sperm and epithelial cells while exhibiting the least negative effect on further downstream analysis; (b) both QIAamp and Lyse-N-Go methods were useful for recovery of DNA from LMD-collected sperm cells; and (c) LMD separation provided clear STR profiles of the male donor with the absence of any additional alleles from the female donor. This report describes an efficient, low-manipulation LMD method for the efficient separation of spermatozoa from two-donor sperm/epithelial cell mixtures.  相似文献   
333.
On The Application of Fuzzy Clustering for Crime Hot Spot Detection   总被引:4,自引:1,他引:3  
   One of the fundamental challenges in crime mapping and analysis is pattern recognition. Efforts and methods to detect crime hot-spots, or geographic areas of elevated criminal activity, are wide ranging. For aggregate data, such as total crime events in a census tract(s), measures of spatial autocorrelation have proven useful. For disaggregate data (i.e. individual crime events), kernel density smoothing and non-hierarchical cluster analysis (e.g. k-means), are widely used. Non-hierarchical techniques are particularly effective in delineating geographic space into areas of higher or lower crime concentrations, because each observation is assigned to one and only one cluster. The resulting set of partitions provides clear-cut spatial boundaries that can be used for hot-spot evaluation and interpretation. However, the strength of non-hierarchical methods can also be viewed as a weakness. Although the hard-clustering of observations into a set of discrete clusters is helpful, there are many cases where ambiguity exists in the data. In such cases, a more generalized approach for hot-spot detection would be helpful. The purpose of this paper is to explore the use of a generalized partitioning method known as fuzzy clustering for hot-spot detection. Functional and visual comparisons of fuzzy clustering and two hard-clustering approaches (medoid and k-means), across a range of cluster values are analyzed. The empirical results suggest that a fuzzy clustering approach is better equipped to handle intermediate cases and spatial outliers.
Tony H. GrubesicEmail:
  相似文献   
334.
Richard Sanders 《当代中国》2006,15(46):113-132
Since the early 1990s, the Chinese government has been promoting organic agriculture as an alternative to the ‘conventional’ agriculture practised in the Chinese countryside. The latter uses increasingly large amounts of chemical fertilisers and pesticides and, as a result, threatens the environmental sustainability of the rural economy. Though absolute numbers of organic farmers remain small, there has been a dramatic increase in their rate of growth since 1995, aided and abetted by the work of the Chinese Organic Food Development Centre (OFDC) in Nanjing established in that year. In 2002, the OFDC gained full international accreditation and recognition, allowing Chinese organic products certified by it to be sold in lucrative markets throughout the world.

At the same time, there is a vigorous debate going on inside China regarding changes in property rights over land, with many scholars advocating full privatisation. This paper, through case study research, contributes to this debate in the context of the extension of organic farming in China. It examines current land rights arrangements in nine organic villages in different parts of the Chinese countryside to investigate whether they are conducive to organic agriculture expansion or hostile to it. On the basis of this research, it argues that the extant ‘partially privatised common property regime’ associated with the Household Responsibility System, when combined with appropriate collective arrangements amongst farmers, can be a satisfactory basis for the adoption of organic agriculture, particularly amongst China's poorest farmers. As a result, it concludes that the Chinese government should encourage those collective arrangements rather than risk new forms of instability as well as environmental unsustainability through wholesale land privatisation.  相似文献   

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This paper identifies from studies made of specific schemes the major social and administrative problems confronting the improvement and extension of small-scale irrigation in Africa. The first section reviews the studies and notes the conclusions to be drawn from each separate one. Underlying these separate conclusions six general problems are identified and in the second section of the article each of these six is elaborated and discussed: the relation between the direct producer'S benefit and wider social benefits: problems of control, commitment to hierarchy, the working of production units, and how to learn from farmers in respect of water use; and finally the general problem of how to plan for the further change that follows after irrigation is introduced.  相似文献   
340.
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