Localization Algorithm of Indoor Wi-Fi Access Points Based on Signal Strength Relative Relationship and Region Division

Precise localization techniques for indoor Wi-Fi access points(APs)have important application in the security inspection.However,due to the interference of environment factors such as multipath propagation and NLOS(Non-Line-of-Sight),the existing methods for localization indoor Wi-Fi access points based on RSS ranging tend to have lower accuracy as the RSS(Received Signal Strength)is difficult to accurately measure.Therefore,the localization algorithm of indoor Wi-Fi access points based on the signal strength relative relationship and region division is proposed in this paper.The algorithm hierarchically divide the room where the target Wi-Fi AP is located,on the region division line,a modified signal collection device is used to measure RSS in two directions of each reference point.All RSS values are compared and the region where the RSS value has the relative largest signal strength is located as next candidate region.The location coordinate of the target Wi-Fi AP is obtained when the localization region of the target Wi-Fi AP is successively approximated until the candidate region is smaller than the accuracy threshold.There are 360 experiments carried out in this paper with 8 types of Wi-Fi APs including fixed APs and portable APs.The experimental results show that the average localization error of the proposed localization algorithm is 0.30 meters,and the minimum localization error is 0.16 meters,which is significantly higher than the localization accuracy of the existing typical indoor Wi-Fi access point localization methods.

Relative Abundance and the Relationships between Aniline,Phenol and Catechol Degraders in Fresh Water

Relative abundance and relationships between aniline, phenol and catechol degraders were investigated in unpolluted and polluted fresh waters in Osaka prefecture, Japan. Phenol and catechol degraders were found more frequently compared to aniline degraders. The results indicate that these degraders were more abundant in polluted waters than in unpolluted waters. Aniline degraders isolated from the Ina River water showed a higher capability of degrading catechol than phenol. Analysis on sequence homology among these three kinds of degraders indicated a possible relationship between aniline degraders and certain strains of both catechol and phenol degraders.

Relationships between two Pseudoalteromonas strains isolated from the Canada Basin and the Southern Ocean using a polyphasic approach

The evolutionary relationships and taxonomic position of two marine planktonic bacterial strains BSw20211 and BSwl0014, isolated from the Canada Basin and from the Southern Ocean, respectively, were determined using a polyphasic taxonomic approach. There was a close phylogenetic relationship between the two strains and most phenotypic properties were shared. Nonetheless, they were found to belong to different species of the genus Pseudoalteromonas on the basis of genotypic analyses. Findings were consistent with the suggestion that gyrB gene sequence comparison and DNA-DNA relatedness might better define phylogenetic relationships of bacteria at the species level. However, a cut-off value of 90% gyrB gene sequence similarity was not reliable for the differentiation of species within the genus Pseudoalteromonas.

一种基于语义关系图的词语语义相关度计算模型

词语的语义计算是自然语言处理领域的重要问题之一,目前的研究主要集中在词语语义的相似度计算方面,对词语语义的相关度计算方法研究不够.为此,本文提出了一种基于语义词典和语料库相结合的词语语义相关度计算模型.首先,以HowNet和大规模语料库为基础,制定了相关的语义关系提取规则,抽取了大量的语义依存关系;然后,以语义关系三元组为存储形式,构建了语义关系图;最后,采用图论的相关理论,对语义关系图中的语义关系进行处理,设计了一个基于语义关系图的词语语义相关度计算模型.实验结果表明,本文提出的模型在词语语义相关度计算方面具有较好的效果,在Word Similarity-353数据集上的斯皮尔曼等级相关系数达到了0.5358,显著地提升了中文词语语义相关度的计算效果.

基于遗传标记的亲缘关系估测方法的建立

【目的】利用分子标记重构动物之间的亲缘关系。【方法】利用分子标记的同源相同特性,通过对一个随机交配的大群体中任意两个个体在某个标记位点4个等位基因的比较,建立估测群体中任意两个个体之间的亲缘关系的方法(记为Liu模型)。【结果】用蒙特卡罗模拟法(Monte Carlo Simulation)随机模拟4种特殊亲缘关系的群体对Liu模型进行了研究,在4种特定的亲缘关系下,与其它几种模型相比较,Liu模型对个体之间亲缘关系的估测最接近模拟群体的真实值,且估测结果稳定。【结论】建立了估测两个个体之间亲缘关系的Liu模型,通过比较分析证明了Liu模型是目前估测效果最好的模型。

论贿赂犯罪的职务关联性

成立贿赂犯罪,要求职务与贿赂之间存在对价关系,具有职务关联性。公务员的职务既包括正当的职务亦包括不正当的职务。下述几种情形可以成立受贿犯罪:(1)公务员不是就现在担当的职务,而是就其一般性职务权限收受贿赂的;(2)就过去担任的职务收受贿赂,如果存在对价性,而且受贿当时具有公务员身份的;(3)公务员就现在尚未担任但将来有可能担任的职务收受贿赂的;(4)不是就公务员本来的职务,而是针对职务密切关联行为收受贿赂的。不过,公务员利用自己的地位或者权限,对相关人员施加影响的,要认定成立受贿犯罪,还需要能将施加影响的行为评价为职务,即便处于能对对方施加某种影响的地位,也不能仅凭这一点就直接认定属于职务密切关联行为。公务员不正当地使用、泄露因职务而获得的信息的行为,难以被直接评价为公务员的职务。

鸟类宿主对西尼罗河病毒传播能力的种间差异性及影响因素

宿主物种对特定病原的传播能力通常具有明显的种间差异性.研究表明,物种的一些生活史特征和其病原传播能力表现出显著的相关性.本研究以虫媒传播型的西尼罗河病毒为例,通过文献检索系统收集了37种鸟类的病原传播能力指数,运用一般线性模型及系统发育比较法,分析了病原传播能力和3种生活史特征(体重、窝卵数及孵化时间)间的关系.一般线性模型和系统发育比较法的结果均表明,宿主物种的3种生活史特征和其病原传播能力间均无显著相关关系;但系统发育比较分析发现,病原传播能力表现出显著的系统发育信号,表明宿主间的亲缘关系能够在一定程度上解释病原传播能力的种间差异性.