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41.
Responses ofRhagoletis pomonella (Walsh) (Diptera: Tephritidae) flies to host fruit visual stimuli (apples or models of apples) and chemical stimuli (synthetic apple volatile blend) were studied in semidwarf field-caged apple trees. Three different fruit or model densities (1, 4, or 16 fruit or models/ tree) and two odor release rates [ca. 0.7g/hr (close to the natural release rate of a ripe apple) and ca. 500g/hr (amount of odor released by commercially sold apple maggot traps)] were tested. Individually released flies were followed as they moved within a tree for a maximum of 20 min. We recorded three-dimensional search paths followed by foraging flies and computed such variables as total relative distance traveled before alighting on a fruit or model, track length between individual alightment sites, and directness of flight to fruits or models. Effect of odor on propensity to alight on fruit or models and host-searching behavior prior to alighting on fruit or on models varied according to fruit or model color and density. If the fruit visual stimulus was strong (e.g., red color), odor did not increase the probability of finding fruit or fruit models. As the visual stimulus became progressively weaker (red to green to clear), odor (irrespective of concentration) appeared to aid flies during the fruit-finding process. As density of fruit or models increased, the probability of flies finding a fruit or model also increased (e.g., 50% of flies found a red fruit model at 1 model/tree while 90% found a red model at 16 models/tree; 4% of flies found a clear model with odor at 1 model/tree while 35% found a clear model with odor at 16 models/tree). Findings reported elsewhere indicate thatR. pomonella flies are able to discover a point source of odor (an odor-bearing tree in a patch of trees) by flying upwind (in the tree patch) in response to intermittent exposure to odor. Findings here indicate that after arrival on a host tree (point source), flies discover individual apparent and abundant host fruit on the basis of vision. If fruit are less apparent or scarce, odor appears to interact with vision during the fruit-finding process.  相似文献   
42.
This paper describes a novel algorithm for numerical optimization, called Simple Adaptive Climbing (SAC). SAC is a simple efficient single-point approach that does not require a careful fine-tunning of its two parameters. SAC algorithm shares many similarities with local optimization heuristics, such as random walk, gradient descent, and hill-climbing. SAC has a restarting mechanism, and a powerful adaptive mutation process that resembles the one used in Differential Evolution. The algorithms SAC is capable of performing global unconstrained optimization efficiently in high dimensional test functions. This paper shows results on 15 well-known unconstrained problems. Test results confirm that SAC is competitive against state-of-the-art approaches such as micro-Particle Swarm Optimization, CMA-ES or Simple Adaptive Differential Evolution.  相似文献   
43.
Behavioral cues to deception are instrumental in detecting deception. As one of the primary sources of deception behavior, text has been analyzed at the level of sub-sentence or message but not the discourse of interaction. Additionally, empirical studies on cues to deception in the case of multiple receivers remain nonexistent. To fill these voids, we propose a discourse framework and six hypotheses about deception behaviors in a multi-receiver environment. The deception behaviors are operationalized by discourse features based on an analysis of real-world data. The results of statistical analysis validate the efficacy of discourse features in discriminating deceivers from truth-tellers.  相似文献   
44.
The promising potential of cloud computing and its convergence with technologies such as mobile computing, wireless networks, sensor technologies allows for creation and delivery of newer type of cloud services. In this paper, we advocate the use of cloud computing for the creation and management of cloud based health care services. As a representative case study, we design a Cloud Based Intelligent Health Care Service (CBIHCS) that performs real time monitoring of user health data for diagnosis of chronic illness such as diabetes. Advance body sensor components are utilized to gather user specific health data and store in cloud based storage repositories for subsequent analysis and classification. In addition, infrastructure level mechanisms are proposed to provide dynamic resource elasticity for CBIHCS. Experimental results demonstrate that classification accuracy of 92.59% is achieved with our prototype system and the predicted patterns of CPU usage offer better opportunities for adaptive resource elasticity.  相似文献   
45.
Flehmen is a stereotyped response of ungulates and other mammals to urine. In black-tailed deer, Flehmen occurs typically in males (rarely in females), and its frequency shows an annual cycle. Flehmen in response to female urine was most frequent in November, and to male urine in January. The response minimum to both types of urine occurred in May. Fifty-five to 100% of initial responses to female urine resulted in Flehmen. The deer responded more often to female urine, and the difference between the responses to female and male urine increased from May to November. A male's own urine released Flehmen more often than did urine of other males. The response intensity varied with the spatial orientation of the male to the urinating female, and responses were usually limited to distances of 15 m or less.  相似文献   
46.
鱼群中的个体如何通过信息传递从而达到一致的群体运动状态,至今还没有刻画这一现象的统一数学模型.本文阐述了一种利用视频数据和传递熵构建鱼群中个体间信息传递网络的方法.首先用实验获取斑马鱼集群的视频数据,并采用计算机视觉跟踪的方法获取鱼群中每个个体的位置和运动速度,然后利用传递熵计算个体两两之间的信息传递关系,在此基础上构建了鱼群信息传递网络.通过网络分析,揭示了鱼群中个体间的信息交互个数与信息传播速度之间的关系,进一步发现了鱼群信息传递网络中的频繁子结构.本文提供了一种利用探测时间序列间因果关系建立鱼群信息传递网络的方法,为鱼群信息传递研究提供了一种新的思路.  相似文献   
47.
ABSTRACT

In this research, the effect of particle size on the surface oxidation and flotation behavior of galena in the lime system was studied. Coarse (?0.074 + 0.038 mm), intermediate (?0.038 + 0.025 mm) and fine (?0.025 mm) galena particles were used in the experiment. The dissolution tests, flotation tests, and sorption tests were accomplished. Through further analysis by XPS, the effect of particle size and lime was observed. The decrease of mineral particle sizes increased the adsorption ratio of collector and the dissolution of galena, while the hydrophilic product OH?/Ca(OH)+ produced by dissolution occupied the dominant position, which led to the minerals hydrophilic.  相似文献   
48.
利用差示扫描量热仪研究了丙烯酸接枝线形低密度聚乙烯(PE-LLD-g-AA)的热学行为,结果表明,与纯线形低密度聚乙烯(PE—LLD)相比,PE-LLD-g-AA的熔融温度(Tm)略有增加,结晶温度(Tc)增加大约4℃,熔融焓(AHm)随AA含量的增加而降低。还利用差示扫描量热仪研究了PE—LLD和PE—LLD-g—AA的等温结晶动力学,用扫描电子显微镜观察了PE—LLD-g—AA等温结晶形态。结果表明,PE-LLD-g-AA的结晶速率大于纯PE—LLD的,随着接枝率的增加,PE-LLD的球晶半径减小,接枝到PE—LLD分子链上的AA分子起到了成核剂的作用。  相似文献   
49.
2903综采工作面是城郊煤矿二水平第一个单顺槽沿空掘巷综采工作面。项目针对该工作面初采、初放期间的矿压显现规律进行了数据采集、分析和总结。  相似文献   
50.
提出了一种基于监控日志挖掘的移动应用用户访问模型自动构造方法,该方法包括监控代码注入和界面访问模型构造两部分。首先,提出了一种监控代码自动注入方法,即通过对移动应用代码的静态分析,自动地在相应位置插入监控代码以支持在运行时动态地监控用户的访问行为。其次,提出了一种基于状态机的移动应用用户访问模型构造方法。访问模型中状态机的节点和节点间跳转上的附加属性描述了UI界面之间的跳转行为和界面内控件的使用情况。对移动应用进行的实验表明,这种基于监控日志挖掘的移动应用用户访问模型自动构造方法能够成功地自动注入移动应用的监控代码,并能够有效获得移动应用用户界面访问行为。  相似文献   
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