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关键词： Land-cover mapping   Classifier accuracy assessment   Image classification   Image heterogeneity   SUPPORT VECTOR MACHINES   COVER CLASSIFICATION   IMAGE CLASSIFICATION   NEURAL-NETWORKS   RANDOM FOREST   ALGORITHMS   TM   METAANALYSIS   AREAS  

摘要： A major issue in land cover mapping is classifier selection. Here we investigated classifier performance under different sample sizes, reference class distribution, and scene complexities. Twenty six 10 km x 10 km blocks with complete reference information across the continental US are used. Per-pixel classification took place using six spectral bands from Landsat imagery. The tested classifiers included Naive Bayes (NB), Support Vector Machine (SVM), K-Nearest Neighbor (KNN), Bootstrap-aggregation ensemble of decision trees (BagTE), artificial neural network up to 2 hidden layers, and deep neural network (DNN) up to 3 hidden layers. For the entire block, our accuracy assessment indicated that all classifiers, with the exception of NB (a Maximum Likelihood variant), performed similarly. However, when we concentrated on edge pixels (pixels at the border of adjacent land cover classes), it was clear that the SVM and KNN offer considerable accuracy advantages, especially for larger reference datasets. Because of their relatively low execution times SVM and KNN would be recommended for classifications using Landsat's spectral inputs and Anderson's 11-level classification scheme. However, both SVM and KNN demonstrated substantial accuracy degradation during the parameter grid search. For this reason, an exhaustive parameter optimization process is suggested. While the ANN and DNN neural network variants did not perform as well, their performance may have been restricted by the lack of rich contextual information in our simple six band per-pixel input space. The effect of class distribution in the training dataset was also evident on the calculated accuracy metric. Gradual accuracy degradation as edge pixel presence increased was also observed. Future work could focus on data-rich classification problems such as change detection using Landsat stacks or expand in high spectral or spatial resolution sensors.

关键词： Sampling  

摘要： The problem of analyzing various methods for the formation of the classified training sample that ensure the effective operation of the automatic compensator for active interferences with simultaneous presence of passive interference is solved in this paper. For the first time an adaptive method for the formation of the classified training sample based on the use of threshold estimation of the interchannel correlation coefficient of the combined interference is proposed. An adaptive method for the formation of the classified training sample based on the current interval estimation of the distribution of the passive component of the combined interference in range (time) is also proposed. The method provides an estimation of the coefficient of interchannel correlation with the selection of the maximum value and its utilization for the formation of weight coefficients in the following probing period. Experiment in the testing ground is conducted with a quantitative estimation of the cancellation ratio of active interference for the formation of the classification sample using spectral differences in the structure of active and passive interferences. © Allerton Press, Inc., 2018.

关键词： Bicycle   Active living research   Built environment   Choice-based conjoint   Sawtooth   Preferences   Physical activity   Infrastructure   Route choice   PHYSICAL-ACTIVITY   NEIGHBORHOOD   WALKING   ADULTS   SCHOOL  

摘要： Installing cycling infrastructure well-separated from motorized traffic is hypothesized to increase children's transportation cycling. However, in some streets it may not be possible to install such cycling paths (e.g. due to financial or space constraints). The current paper investigates which physical factors could increase parents' perceptions of environmental supportiveness for children's transportation cycling, across six different types of cycling infrastructure. Parents completed a choice-based conjoint task by indicating which photographed street they preferred to let their child cycle along. The streets were experimentally manipulated on 7 physical factors (e.g. traffic speed, vegetation). Interactions between type of cycle path and the other environmental factors were identified. When no or limited separation from motorized traffic is present, street characteristics increasing parents' safety perceptions (traffic density and speed) should be prioritized when aiming to improve the supportiveness of streets for children's transportation cycling. Comfort and aesthetics can further improve streets' environmental supportiveness when cycling paths are more separated from traffic.

关键词： QC小组   质量管理   检验  

摘要： 在质检机构提高发展质量和效益的背景下,检验机构持续通过开展QC小组活动,推动检验技术和技术改造和创新的发展,QC小组活动作为全面质量管理的一项重要工作,广泛的开展QC小组活动,是实现全员参与质量改进的有效方法,是提高检验水平和技术改造及创新的有效途径.

关键词： 检验科   医院感染   预防   管理措施  

摘要： 目的:探讨检验科在预防医院感染中的作用,提出加强实验室的管理和宣传教育等措施.方法:根据分析近三年来我院消毒灭菌合格率表和探讨预防医院感染的相关措施.结果:加强对医院消毒工作的管理来降低院内感染率是有实际意义的.结论:加强预防措施,可有效地防止院内感染.

关键词： 形式   形式瑕疵   履行补正  

摘要： 法律行为的形式自罗马法以来就十分重要。当时虽然没有法律行为的概念,但是人们认为某个行为所能够产生的法律效果与形式紧密相连,“无形式则无行为”,因此形式是绝对形式。现代法治国家都确立了形式自由的原则。但是,例外地也会有形式强制。我国在民事法律的许多具体规定中也规定了形式要求。不过,我国合同法缺乏关于欠缺形式的合同效力的规定,仅仅是在第36条规定了形式瑕疵补正的规则。本文主要围绕履行补正形式瑕疵一般规则合理性展开讨论,并简要探讨了补正规则的具体适用。本文具体内容安排包括:第一章讨论形式和意思表示、法律行为之间的关系。本文所说的形式并非意思表示的载体,而是与意思表示密切相关、但相互分离的一种外在表现方法。现代社会对于形式的关注不再是意思表示的表达,而是其他利益保护的需求。尤其在合同情形中,形式与当事人的合意是可以独立的。第二章讨论我国合同法上形式瑕疵的效力问题。比较法上,虽然各个国家具体的规定皆有不同,但是本质上都将欠缺形式的合同作为无效处理或者不具备强制执行的效力。在我国,虽然《合同法》和其他法律规定了需书面形式的合同,但是都没有规定欠缺形式时的法律后果。从意思表示的角度出发,结合形式的具体功能,法定形式瑕疵的合同应为无效。在约定形式瑕疵的情况下,若形式仅为证明效力,则合同效力不受影响;若形式作用重大或者约定不明,则意思表示尚未生效,合同不成立。第三章讨论履行治愈形式瑕疵的可能性。从制度上而言,比较法上各国基本都存在履行治愈形式瑕疵的规定或者判例,我国也是如此。而履行之所以能够治愈形式瑕疵,则根本上在于形式目的的完成、相对人信赖的保护。而在法律行为因形式瑕疵而无效时,当事人履行合同则适用不当得利法的规定,当事人的不当得利返还请求权不受影响。第四章讨论在我国现有制度上履行治愈瑕疵一般化规定的合理性。在我国,由于合同法上形式功能相对弱化,因此我国合同形式的目的也较为单一且容易被其他行为或者事实所替代和完成,此时形式的立法目的既已实现,则合同的效力不受阻碍。其次,我国合同形式的种类与国外相比也大有不同,数量很少,也限制形式功能的发挥。第五章讨论我国《合同法》第36条具体适用。首先,第36条仅适用于法定形式瑕疵的情况。其次,主要义务原则上指的是合同的主给付义务,特殊情况下,从给付义务和附随义务的履行也可能达到治愈效果。再者,一方的履行并不指其对于合同义务的完全履行,部分履行经常也会治愈合同瑕疵。除此之外,瑕疵治愈对于合同没有溯及力。

关键词： 宫颈癌腔内放疗   局部感染   细菌学检验  

摘要： 目的:研究细菌学检验对宫颈癌腔内放疗合并局部感染患者临床治疗的作用.方法:本次研究选取的研究对象为2016年7月11日至2017年7月12日期间在我院进行治疗的宫颈癌腔内放疗合并局部感染患者80例,对照组(n=40)由医生评估患者的感染程度后进行经验性抗生素用药,观察组(n=40)根据细菌学检验结果 并结合患者的实际情况予以个体化抗生素用药.将两组患者的临床疗效、并发症发生情况进行比对.结果:观察组宫颈癌腔内放疗合并局部感染患者的临床总有效率更高且并发症发生率更低,P<0.05.结论:细菌学检验应用在宫颈癌腔内放疗合并局部感染患者的临床治疗中能够对抗菌方案进行优化,提高临床疗效和用药安全性.

关键词： 船舶电气   接地故障   查找   处理  

摘要： 在造船业开始时,生产和检验是整合的,即船舶制造商是检验员.随着生产力的不断发展,车间范围逐渐扩大,产量不断提高.研讨会的主人不仅能够亲自处理所有管理事务.因此,车间所有者和不同生产主人的专家将分开进行检查.生产和检验实际上是一个凝聚力和协调的整体,检验是生产的一个组成部分.它是造船过程中的重要组成部分,特别是海洋现代化和自动化生产线的两条不同路线.可以说,没有检查就无法做到生产.特别是在造船业中,减少质量检查工作和中断质量检测的机构是绝对不可以的.

关键词： 合同价格形式   结算   风险利弊  

摘要： 在当今建设工程施工合同价格的核算中,通用核算形式大致可分为三种:固定总价、 固定单价、 成本加酬金.在合同范本的选择上,一般经常采用的是总价包干和综合单价这两种形式.而施工合同价格的形式,又决定了结算审计工作过程中的难易程度,以及审核风险的高低.本文将从合同性质、 核算方式、 适用范围、 结算审计难度、 风险利弊等角度,浅淡三种施工合同价格形式对于结算工作的各方面影响.

关键词： 痕迹检验技术   刑事技术   地位   作用  

摘要： 痕迹检验技术是警方刑事侦查经常运用的一种刑侦方法,属于刑事研究领域一项司法鉴定工作,能为案件侦破提供详实的参考依据.本文对痕迹检验技术对案件侦破的作用和重要性进行了分析,以期为公安机关侦查工作提供有益借鉴.