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排序方式: 共有877条查询结果,搜索用时 15 毫秒
871.
Policy Sciences - In June 2018, President Trump directed the development of a sixth branch of the US Armed Forces—the Space Force—whose primary mission is to enhance the space...  相似文献   
872.
873.
Environmental regulatory design addresses scientific uncertaintythrough a range of regulatory design tools. The seven approachesidentified and considered in this article are termed (1) theacknowledgement of scientific uncertainty (2) the burden shiftingapproach (3) the ‘sound science’ approach (4) theconsequences approach (5) the consensus approach (6) the estimationapproach and (7) the adaptive management approach. Analysisof some common environmental legislative frameworks suggeststhat, rather than occurring in isolation, these seven approachesare frequently incorporated into legislative regimes in a multitudeof combinations. The article also highlights the implicationsof expressly embedding a precautionary approach within pre-existingenvironmental regulatory frameworks, such as has occurred withinAustralian environmental regimes. Finally, the article exploresthe advantages and disadvantages of each approach and the variouscircumstances that favour the adoption of a particular regulatoryapproach to scientific uncertainty. In doing so, it suggestsan agenda for future empirical research on approaches to regulatorydesign for scientific uncertainty.  相似文献   
874.
Image segmentation is a fundamental precursor to quantitative image analysis. At present, no standardised methodology exists for segmenting images of fluorescent proxies for trace evidence. Experiments evaluated (i) whether manual segmentation is reproducible within and between examiners (with three participants repeatedly tracing three images) (ii) whether manually defining a threshold level offers accurate and reproducible results (with 20 examiners segmenting 10 images), and (iii) whether a global thresholding algorithm might perform with similar accuracy, while offering improved reproducibility and efficiency (16 algorithms tested). Statistically significant differences were seen between examiners’ traced outputs. Manually thresholding produced good accuracy on average (within ±1% of the expected values), but poor reproducibility (with multiple outliers). Three algorithms (Yen, MaxEntropy, and RenyiEntropy) offered similar accuracy, with improved reproducibility and efficiency. Together, these findings suggest that appropriate algorithms could perform thresholding tasks as part of a robust workflow for reconstruction studies employing fluorescent proxies for trace evidence.  相似文献   
875.
Cannabinoid hyperemesis syndrome (CHS) is one of the more clinically challenging effects of cannabis consumption. It is characterized by cyclic attacks of nausea and vomiting in chronic cannabinoid users and learned behavior of compulsive hot bathing. The deaths of a 27‐year‐old female, a 27‐year‐old male, and a 31‐year‐old male with a history of CHS are reported. The decedents had a history of cyclical nausea and vomiting, chronic cannabinoid use and negative laboratory, radiological and endoscopic findings. All presented to the emergency department with nausea and vomiting in the days preceding death and were treated symptomatically. Toxicological analysis revealed tetrahydrocannabinol in postmortem blood. The cause of death of two of the three cases was attributed to CHS. CHS was appreciated in the third case but was not the cause of death. These three cases demonstrate the importance of recognizing CHS as a potential cause or contributing factor to death in cannabinoid user.  相似文献   
876.
The Journal of Technology Transfer - This study explores how service firms in an open exchange of knowledge protect themselves against opportunistic behavior while trying to acquire some knowledge...  相似文献   
877.
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