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1.
Professional search in patent repositories poses several unique challenges. One key requirement is to search the entire affected space of concepts, following well-defined procedures to ensure traceability of results obtained. Several techniques have been introduced to enhance query generation, preferably via automated query term expansion, to improve retrieval effectiveness. Currently, these approaches are mostly limited to computing additional query terms from patent documents based on statistical measures. For conceptual search to solve the limitation of traditional keyword search standard dictionaries are used to provide synonyms and keyword phrases for query refinement. Studies show that these are insufficient in such highly specialized domains. In this paper, we present an approach to extract keyword phrases from query logs created during the validation procedure of the patent applications. This creates valuable domain-specific lexical databases for several specific patent classes that can be used to both expand as well as limit the scope of a patent search. This provides a more powerful means to guide a professional searcher through the search process. We evaluate the lexical databases based on real query sessions of patent examiners.  相似文献   
2.
Experimental tests showed that poststrike elevation in tongue-flicking rate (PETF) and strike-induced chemosensory searching (SICS) in the gila monster last longer than reported for any other lizard. Based on analysis of numbers of tongue-flicks emitted in 5-min intervals, significant PETF was detected in all intervals up to and including minutes 41–45. Using 10-min intervals, PETF lasted though minutes 46–55. Two of eight individuals continued tongue-flicking throughout the 60 min after biting prey, whereas all individuals ceased tongue-flicking in a control condition after minute 35. The apparent presence of PETF lasting at least an hour in some individuals suggests that there may be important individual differences in duration of PETF. PETF and/or SICS are present in all families of autarchoglossan lizards studied except Cordylidae, the only family lacking linguallly mediated prey chemical discrimination. However, its duration is known to be greater than 2-min only in Helodermatidae and Varanidae, the living representatives of Varanoidea. That prolonged PETF and SICS are typical of snakes provides another character supporting a possible a varanoid ancestry for Serpentes. Analysis of 1-min intervals showed that PETF occurred in the first minute. A review of the literature suggests that a pause in tongue-flicking and delay of searching movements are absent in lizards and the few nonvenomous colubrid snakes tested. The delayed onset of SICS may be a specific adaptation of some viperid snakes to allow potentially dangerous prey to be rendered harmless by venom following voluntary release after envenomation and preceding further physical contact with the prey.  相似文献   
3.
A very simple algorithm for computing all k nearest neighbors in 2-D is presented. The method does not rely on complicated forms of tessellation, it only requires simple data binning for fast range searching. Its applications range from scattered data interpolation to reverse engineering.  相似文献   
4.
一种有机化合物名称编码与亚结构检索方法   总被引:1,自引:0,他引:1  
本文以 IUPAC 为基础,考虑有机化合物母体和取代基的关联,采用库中已有的化合物名称进行亚结构检索,这种检索方法,由于由化合物名称所劈裂的编码数量较少,所以索引文件小,检索速度较快。另外,这种方法是侧重在化学上有意义的母体和宫能团,它可以和碎片编码亚结构检索方法互相补充。  相似文献   
5.
穷举法是程序设计中经常用到的一种算法,用来解决一些用常规的数学方法无法解决的问题.文章通过两个典型的例子对穷举法的思路和有关注意事项进行了分析,供编程学习者参考.  相似文献   
6.
超声波压力检测中回波搜索算法   总被引:2,自引:0,他引:2  
王爱明  李艾华 《机床与液压》2003,(5):280-281,114
通过对超声波压力测量中回波信号特征的分析,提出了回波自动搜索算法。该方法把快速傅立叶变换方法和小波多分辨率信号分解相结合,精确地检测出回波的包络信号,从而准确地搜索到回波,为后续的压力信号处理及提高压力测量的精度奠定了基础。  相似文献   
7.
针对现有大区域范围路径规划算法存在的一些问题,提出一种限制搜索区域的多比例尺最优路径规划算法。该算法在进行路径规划时,一方面根据路网的多比例尺信息对路网进行分级,另一方面对搜索区域进行合理限制。测试实验表明此算法可以提高路径规划的效率。  相似文献   
8.
As a response to attack by herbivores, plants can emit a variety of volatile substances that attract natural enemies of these insect pests. Predators of the banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae) such as Dactylosternum abdominale (Coleoptera: Hydrophilidae) and Pheidole megacephala (Hymenoptera: Formicidae), are normally found in association with weevil-infested rotten pseudostems and harvested stumps. We investigated whether these predators are attracted to such environments in response to volatiles produced by the host plant, by the weevil, or by the weevil–plant complex. We evaluated predator responses towards volatiles from banana pseudostem tissue (synomones) and the synthetic banana weevil aggregation pheromone Cosmolure+ in a two-choice olfactometer. The beetle D. abdominale was attracted to fermenting banana pseudostem tissue and Cosmolure+, whereas the ant P. megacephala was attracted only to fermented pseudostem tissue. Both predators were attracted to banana pseudostem tissue that had been damaged by weevil larvae irrespective of weevil presence. Adding pheromone did not enhance predator response to volatiles from pseudostem tissue fed on by weevils. The numbers of both predators recovered with pseudostem traps in the field from banana mats with a pheromone trap were similar to those in pseudostem traps at different distance ranges from the pheromone. Our study shows that the generalist predators D. abdominale and P. megacephala use volatiles from fermented banana pseudostem tissue as the major chemical cue when searching for prey.  相似文献   
9.
结合高效的动态格点搜索(DLS)算法与扰动操作(Perturbation Operation)提出一种新的改进方法(DLS-PO),用于确定团簇的最低能量结构。针对一个特定构型,DLS算法总能给出其对应搜索空间的最规则结构。然而,一次失败的DLS优化将消耗大量的运算资源。为此,采取原子移动和结构旋转的扰动操作成功地改变了构型,再结合后续的DLS操作,提高了优化效率。将该算法用于原子数高达309的Lennard-Jones团簇及100原子NP-B函数铝团簇的结构优化。优化结果显示相比于DLS算法,DLS-PO算法更为高效。  相似文献   
10.
The origin of olfactory stimuli involved in the host microhabitat location inCotesia flavipes, a parasitoid of stem-borer larvae, was investigated in a Y-tube olfactometer. The response of femaleC. flavipes towards different components of the plant-host complex, consisting of a maize plant infested with two or more larvae of the stem borerChilo partellus, was tested in dualchoice tests. The concealed lifestyle of the stem-borer larvae did not limit the emission of volatiles attractive to a parasitoid. A major source of the attractive volatiles from the plant-host complex was the stem-borer-injured stem, including the frass produced by the feeding larvae. Moreover, the production of volatiles attractive to a parasitoid was not restricted to the infested stem part but occurs systemically throughout the plant. The uninfested leaves of a stem-borer-infested plant were found to emit volatiles that attract femaleC. flavipes. We further demonstrate that an exogenous elicitor of this systemic plant response is situated in the regurgitate of a stem-borer larva. When a minor amount of regurgitate is inoculated into the stem of an uninfested plant, the leaves of the treated plant emit volatiles that attract femaleC. flavipes.  相似文献   
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