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排序方式: 共有110条查询结果,搜索用时 15 毫秒
61.
针对未来医疗信息系统中采用轻量级射频识别(RFID)技术的安全与隐私保护问题,构建了医疗信息系统的通用流程模型,并由此提出了既有安全协议的改进方案.新方案利用业务流程中前导关联信息缩减搜索空间.安全分析表明,新方案能够有效平衡不可追踪性与伸缩性矛盾需求,抗击各类攻击,支持RFID标签复用,且与既有EPC C1G2标准兼容. 相似文献
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63.
James Crossland 《新西兰海洋与淡水研究杂志》2013,47(3):255-261
The results of three snapper tagging cruises in the Hauraki Gulf area to estimate population size and annual exploition rate are presented. Eight hundred and thirty‐two snapper were tagged around Great Barrier Island in August 1975; in the inner Hauraki Gulf 1743 were tagged in June 1976 and 2685 in October 1976. Estimates of tag loss due to the combined effect of shedding of tags and tagging mortality were made, and the crude tag return rates were adjusted accordingly. The combined returns from commercial and amateur fishermen for the first year after tagging, adjusted for tag loss, were: Great Barrier Island, 19 (2.3%); inner Hauraki Gulf, June tagging, 98 (5.7%), October tagging, 179 (6.8%). Tag return rates from different parts of the study area varied considerably. Calculations of the population size for the inner Hauraki Gulf (fishery statistical areas 006 and 007) were made from tag returns of longline and set net fishermen and their catch statistics taken from the monthly fishing returns; Petersen's method gave population sizes of 43 million (returns from June tagging) and 36 million (October). The catch statistics are thought to considerably under‐record the real landings, and better estimates of the population size may be 71 million and 60 million respectively. 相似文献
64.
J. H. R. Lesser 《新西兰海洋与淡水研究杂志》2013,47(4):357-370
The complete series of phyllosoma larval stages of spiny lobster lasus edwardsii are described. Eleven stages are recognised from specimens captured in plankton samples collected along a transect extending 185 km east of Castlepoint, North Island, New Zealand between July 1969 and December 1971. A table of distinguishing characteristics and a key for identification of stages are presented. First stage larvae occur between August and October and last stage larvae about 15 months later. Mortality through the phyllosoma stages is estimated to be 98%. Early stage larvae occur mainly inshore in Southland Current water in the upper 5 m, and later stage larvae occur more frequently offshore in East Cape Current water at 40–60 m depth. 相似文献
65.
Tag recovery rate is an important parameter for estimating exploitation and natural mortality in fished populations. Passive integrated transponder (PIT) technology can record 100% of PIT tagged animals passing within the detection limit of a PIT tag scanner. However PIT tags and PIT tag scanners are expensive compared with conventional visual tags and PIT tags are not detectable without scanners. We used simulation to evaluate the hybrid PIT tag which has the PIT tag incorporated into a conventional tag allowing both electronic detection capability by a scanner and visual detection by fishers. Simulated estimates of the precision and accuracy of exploitation and natural death rates for two lobster fishery management regimes: a 7‐month season for both sexes and a fishery with a 10‐ and 6‐month season for males and females, respectively, were used to determine the benefit of PIT tags. For a project budget of AU#DL200,000, hybrid PIT tags and 10% of the fleet being equipped with scanners produced more precise and accurate estimates of exploitation rate and natural death rate until tag reporting rate by fishers exceeds 40% for the two‐gender management regime and 90% for the 7‐month combined sex regime. Increasing the number of scanners to 20% of the fleet resulted in fewer hybrid PIT tags being inserted for the same cost and did not improve the precision or accuracy of estimates. Increasing the number of lobsters tagged by tagging during a higher catch rate period improved the precision of exploitation and natural death rate estimates at lower tag reporting rates for the conventional tag scenario, but did not alter the tag reporting rate required to make conventional tagging more beneficial than hybrid PIT tagging. Increased tag reporting rate by the 90% of the fleet that were not equipped with scanners had no significant impact on the precision or accuracy of estimates for either management regime. 相似文献
66.
Peter L. Horn 《新西兰海洋与淡水研究杂志》2013,47(3):623-631
In late 1987, bluenose (Hyperoglyphe antarctica) were tagged with streamers attached to fish hooks, at six commercial fishing grounds between Gisborne and Cape Palliser, New Zealand. The tagged hooks were fished on commercial trot lines, but were attached with traces of 5.5 kg breaking strain nylon that broke when the fish took the hook and struggled to escape. Based on catches from full strength control lines fished simultaneously with the detachable gear, 1971 bluenose were tagged. In the subsequent 8.5 years, 44 tagged bluenose (where both the sites of tagging and recapture where known) were recaptured. All but seven of these returns occurred in the first year after tagging, indicating that the rate of long‐term tag retention was not good. Bluenose appeared to be relatively sedentary in the short term, but were capable of quite rapid and extensive movement. Four tagged fish had travelled distances in excess of 450 km, with movements to both the north and south of the tagging area. These data indicate that bluenose off the eastern coast of New Zealand between North Cape and Kaikoura probably comprise a single biological stock. 相似文献
67.
《African Journal of Marine Science》2013,35(3):365-372
Understanding differences in the recapture rate between different tags (A-, B- and C-types), capture methods (rock-and-surf anglers, scientific divers and Natal Sharks Board protection nets) and life-history stages (juvenile and adult) is critical in evaluating the results obtained from cooperative tagging programmes (CTPs). A generalised linear modelling approach, using a log-linear model, was used to determine significant differences in the probability of recapture between these various factors using data from the Oceanographic Research Institute and Port Elizabeth Museum CTPs. Between 1984 and 2004, a total of 3 385 raggedtooth sharks Carcharias taurus was tagged by volunteers from both programmes along the east coast of South Africa. A likelihood ratio test indicated significant differences in the probability of recapture between A- and C-type and B- and C-type tags (p < 0.01), between different capture methods (p < 0.05) and between juvenile and adult sharks (p < 0.01). A comparison of recapture rates between members of the CTPs also indicated a marked variability in the performance of individual taggers. The study highlights important data-quality issues inherent in large CTPs. 相似文献
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69.
智能交通系统应用的迅猛发展需要高质量的交通数据,而交通数据采集技术采集到的原始数据会不可避免地混入异常数据,降低数据的有效性,从而可能引起系统应用性能的降低.本文针对基于无线射频技术(RFID)的交通数据,设计了一套交通数据评价指标,并根据交通数据评价指标的特点,综合评价权重向量计算方法的适用条件及优缺点,建立了基于IOWA(Induced Ordered Weighted Averaging)算子的交通数据综合评价方法.基于实际数据的分析结果表明,该方法可以对RFID交通数据进行有效性评价. 相似文献
70.
在管线CAD系统中,经常会对管线进行扯旗标注,以用于地图打印、出图等。本文基于Auto CAD提供的.NET类型的API,在管线扯旗标注中采用Jig技术,实现标注过程的动态性交互,标注过程可动态预览。 相似文献