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关键词： 林业   木材检验   作用   地位   经济效益  

摘要： 林业资源是人类生存发展和社会经济发展的保障,培育和开发利用林业资源是我们的重要职责。但是目前可采的林木资源逐渐短缺,必须通过提高木材的利用率将有效的资源条件进行经济效益最大化。因此木材检验工作是至关重要的,和企业的经济收益密切相连。本文简单介绍了木材检验的含义,对作用和地位做了分析,关于做好木材检验工作提出了一些策略,以期对该领域研究有指导意义。

关键词： 城市生活垃圾   包装废弃物   固体废物处置   资源化   类推   循环回收   全过程管理   无害化处理  

摘要： 我国城市生活垃圾每年超过1.5亿吨,并以每年8%到10%的速度递增。688座城市,除县城外已有2/3的大中城市陷入垃圾包围中,有1/4城市已没有合适场所堆放垃圾。我国城市每年因垃圾造成的资源损失价值在250至300亿元,垃圾中包装废弃物占到15%以上,由于电商快速发展,包装废弃物呈明显上升状态,形势十分令人担忧。国际社会对包括快递包装在内的固体废物处置达成了较为普遍的共识,即按照废物层次原则对固体废物进行全过程管理,从处置策略上按照事前预防(尽量不产生废物)、减量、重复使用、循环回收、能源回收(焚烧发电等)和无害化处理,即国外对包装从源头就开始筹划,让包装物循环或再生利用,产生数量最少的废物。

关键词： Android malware   frequent subgraph   familial classification  

摘要： The rapid increase in the number of Android malware poses great challenges to anti-malware systems, because the sheer number of malware samples overwhelms malware analysis systems. The classification of malware samples into families, such that the common features shared by malware samples in the same family can be exploited in malware detection and inspection, is a promising approach for accelerating malware analysis. Furthermore, the selection of representative malware samples in each family can drastically decrease the number of malware to be analyzed. However, the existing classification solutions are limited because of the following reasons. First, the legitimate part of the malware may misguide the classification algorithms because the majority of Android malware are constructed by inserting malicious components into popular apps. Second, the polymorphic variants of Android malware can evade detection by employing transformation attacks. In this paper, we propose a novel approach that constructs frequent subgraphs (fregraphs) to represent the common behaviors of malware samples that belong to the same family. Moreover, we propose and develop FalDroid, a novel system that automatically classifies Android malware and selects representative malware samples in accordance with fregraphs. We apply it to 8407 malware samples from 36 families. Experimental results show that FalDroid can correctly classify 94.2% of malware samples into their families using approximately 4.6 sec per app. FalDroid can also dramatically reduce the cost of malware investigation by selecting only 8.5% to 22% representative samples that exhibit the most common malicious behavior among all samples.

关键词： chemometrics   classification techniques   conventional chocolate   essential and toxic elements   organic chocolate  

摘要： Chocolate is an appreciated food derived from cacao fruit. The flavonoids and minerals present in the chocolate have benefits to health, and some specific minerals are known to be toxic. Because of differences in their production systems, organic chocolate has a distinguishable pattern in mineral concentrations than conventional chocolate. Aiming for authenticity and study of the toxic elements in organic chocolate, we present in this work a simple method to classify organic chocolate samples based on elemental fingerprint profiling and multivariate data analysis. Thirty-eight elements (toxic and essential) were determined in 36 chocolate samples (organic and conventional) by using inductively coupled plasma mass spectrometry to establish reference ranges and to identify differences in patterns of elements in both type of samples. Our results showed that Al, Zn, Mn, Cu, and Ba are the most present components for both types of chocolate, and higher concentrations of essential elements Fe, Zn, and Mg are found in conventional type, opposing the idea that organic food is rich in essential elements. Principal component analysis and linear discriminant analysis were used for multivariate data analysis, and sample differentiation was possible with 83% accuracy. We present a method to differentiate organic from conventional chocolate based on elemental fingerprint profiling and multivariate data analysis. Thirty-eight elements (toxic and essential) were determined in samples by inductively coupled plasmamass spectrometry. We found that Al, Zn, Mn, Cu, and Ba are the most commonly present elements for both types of chocolate, whereas higher concentrations of essential elements Fe, Zn, and Mg are found in the conventional samples.

关键词： 尿常规   甲状腺功能亢进   诊断   作用分析  

摘要： 分析尿常规检验对甲状腺功能亢进患者诊断的作用。方法:选择甲状腺功能亢进症患者,共计60例(研究组),2016年10月~2017年10月为检查期间,同期选择健康人60例作为对照组,使用尿常规检验所有研究对象,比较组间研究对象的尿比重,尿液PH值,尿糖检查结果、尿胆红素结果、尿酮体检查结果、尿蛋白检查结果呈阳性率。结果:研究组的尿比重与对照组相比更高,且尿液PH值与对照组相比更低,差异显著,P<0.05;研究组的尿糖检查结果、尿胆红素结果、尿酮体检查结果、尿蛋白检查结果呈阳性例数分别有:7例、8例、25例、20例,而对照组则无上述呈阳性例数,差异显著,P<0.05。结论:尿常规检验对甲状腺功能亢进患者的诊断作用显著,可以辅助临床医生诊断甲状腺功能亢进症患者。

关键词： 肾上腺皮质疾病   生化检验   常规检验  

摘要： 目的:阐述生化检验应用于肾上腺皮质疾病诊断里的作用。方法:从本院2017年6月~2018年6月收治的肾上腺皮质疾病患者中挑选50人进行临床研究,随机、平均的把患者分成每组25人的对照组与观察组,对照组患者行常规检验,观察组患者行生化检验,最终比较检验有效率。结果:经过检验研究发现,在检查有效率比较中,观察组的92.0%明显优于对照组的80.0%,且P <0.05,数据差异存在统计学研究价值。结论:将生化检验诊断方法引入肾上腺皮质疾病中进行使用,具有准确率高、可靠度高等优点,应在疾病例行检查项目中加入生化检验诊断项目。

关键词： 肝硬化   凝血四项指标   检验   临床作用  

摘要： 目的:研究肝硬化患者凝血四项指标的检验及其临床作用.方法:选择2016年3月—2017年3月到医院就诊的肝硬化患者42例作为观察组,同期选择健康体检查42例作为对照组.两组研究对象均进行凝血四项指标检验.对比各项指标的检验结果.结果:观察组TT(21.65±4.52)s,PT(18.46±3.55)s,APTT(41.58±9.24)s,均高于对照组;FIB(1.47±0.35)g/L,低于对照组,均具有显著差异(P<0.05).结论:肝硬化患者和健康者相比,在凝血四项指标方面均存在显著差异,可利用这些指标评价患者凝血功能,进而为疾病诊断和治疗提供依据.

关键词： 特种设备   安全管理   检验机构  

摘要： 与其他普通设备不同,特种设备是跟人身安全有直接关系的,而且它一种极具危险性的设备,在我国的很多行业中,具有着非常重要的地位。所以在安全管理中,要特别注意到特种设备的状态。所谓的检验机构,就是对特种设备的安全性能进行检验的机构,在检验时,检验机构能够到被检测设备的使用现场,利用所有的独特的检验设备和各种先进仪器,对需要检测的设备进行安全的检查和验收管理,检测人员会结合自己的专业知识,将会发现设备中可能会出现的种种问题,这样能够有效的避免现场发生安全事故。这篇文章对特种设备的检验机构进行了概述,并且分析了特种设备安全管理中检验机构所发挥的作用。