反光镜法在车架号码检验中的应用

在经济利益的驱动下,犯罪分子在盗抢汽车后,通常会改动汽车发动机号码或车架号码,制作假牌、套牌,掩盖其原来的号码,以躲避侦查打击。侦查人员只有通过检验、发现和还原盗抢车辆的原始号码才能为案件的侦破提供证据。笔者在多年刑事技术检验过程中,摸索出一种非常规的机动车辆车架号码的检验方法—反光镜法。该方法针对被盗抢车辆的发动机号码完全被更改,无法通过常规的检验方法显现车辆原始号码的情况下,从车架号码入手,利用反光镜法显现车架原始号码,达到很好的检验鉴定效果。     

铝质发动机号码被锉改后的显现

随着我国经济的发展,人民生活水平的不断提高,单位、个人汽车拥有量日益增加,然而汽车被盗抢的案件也日益增多[1]。自2003年以来,石家庄市公安局刑警支队受理了各基层单位,送检涉嫌被盗抢嫌疑车辆的锉改号码显现案件达1100余件。在工作中,我们总结出一套针对铝质材质发动机号码被锉改后显现的新方法,并且成功的应用于实际案件当中,为侦查破案提供了可靠的依据。现将该方法介绍如下。1显现原理1.1号码显现的金属化学动力能[2]车辆号码印压在发动机部位上,使客体表面形成较深的凹陷字迹作为标识。金属被冲压字迹部位,一方面由于外界冲力作用,…     

塑料制品上锉除文字的显现研究及原理讨论

目的研究塑料制品上损毁文字的加热显现方法,探讨显现原理;方法将盗窃案涉及的常见塑料客体上的凸面文字进行锉除,对文字消除部位进行加热显现;结果清晰显现了几种常见塑料客体上的消除字迹;结论在利用加热法显现塑料客体上消除的文字时,塑料表面损毁程度、客体材质、生产工艺等因素对显现结果产生重要影响。     

远红外加热无损显现渗透性客体上指印初探

在指印显现实践中,渗透性客体上的汗液指印显现方法主要是有损显现,对此,本实验尝试建立远红外加热无损显现渗透性客体上汗液指印,介绍如下。1材料和方法1.1材料检材加温设备：HGXJ-807潜在手印无损显现系统（上海恒光警用器材有限公司）,HGXJ-447nm激光生物显现仪（上海恒光警用器材有限公司）,NIKON单反数码照相机,447nm干涉滤光镜。1.2方法（1）将HGXJ-807潜在手印无损显现系统通上电,预加热5min~6min,箱内温度设置185℃。     

十大技防产品的应用与发展系列报道之三：车辆防盗报警系统的应用与发展

车辆防范的主要目的是防止有人未经许可利用车辆自身的发动机驱动车辆-即防止整车被盗，再就是防止他人(包含使用工具)侵入车辆内部(如乘员厢、行李厢、发动机仓等)进行盗窃和破坏，可简单归结为“防止使用发动机、防止入侵”。应用的具体防范手段主要包括：     

用热水加温加湿“502”胶显现车辆内手印

笔者在工作中,摸索出一种用“502”胶显现车辆内手印的方法。这种方法适用轿车、面包车、农用车、挖掘机等各类车辆（驾驶室）内的手印显现,通过控制车内温度和湿度,“502”胶熏显速度达到一个较好的显现效果。现以柳州五菱面包车为例进行实验。     

热塑性塑料制品上被挫字迹的显现探讨

目的探讨热塑性塑料制品上被挫字迹的显现方法。方法采用局部加热的方法对热塑性塑料制品上被挫字迹进行显现。结果较好的显现出了凹陷状的字迹形态。结论该方法显现效果可靠，操作简单，显现迅速。     

卫生纸上汗潜手印显现方法比较研究

目的通过比较实验来探寻卫生纸上汗潜手印的最佳显现方法,为实际工作提供指导性建议。方法选择市面上常见的四种卫生纸,在每种卫生纸上制作汗潜指印实验样本,分别将茚三酮溶液浸泡法与茚二酮溶液浸泡法、茚二酮溶液浸泡法与茚二酮溶液超声雾化法、茚二酮溶液超声雾化法与(对)-二甲(替)氨基肉桂醛(DMAC)显现纸冷熏法、茚二酮溶液浸泡法与红外加热显现法、茚二酮溶液超声雾化后加热显现法与室温显现法进行两两比较,分析显现效果。结果茚二酮显现的灵敏度和质量均优于其他几种方法,特别是超声雾化后室温显现,既能很好地显现手印又不影响后期的DNA检验。结论采取茚二酮超声雾化室温条件显现方法显现卫生纸上的汗潜手印具有显现效果好、设备条件要求低、操作性强的特点,在实际案件中可以借鉴应用。     

微量加热成像技术显现热敏纸汗潜手印

利用英国Consolite Forensics公司生产的Hot Print System热敏纸快速手印显现仪(简称HPS)。通过微量加热成像技术,使汗潜手印变黑而显出纹线,新鲜或陈旧手印均有较好的显现效果。该技术具有操作简单、快速安全、无需化学试剂、显现效果明显的特点,可以作为一种显现热敏纸上汗潜手印的常用方法。     

新型荧光502粉末显现手印技术的改进研究

目的 对新型粉末状荧光502显现手印的方法进行进一步探索和完善,确保其高效便捷和科学准确.方法 将PolyCyano UV粉末加热至230℃使其升华,待该粉末在手印纹线上聚合附着后用长波紫外线或蓝光激发拍照,并与初步研究结果相比较.结果 大部分非渗透性光滑客体表面上的汗潜手印均有很好的显现效果.结论 该方法使显现流程更加高效便捷、显现时间短、无需二次染色增强、不破坏生物检材,适合推广使用.     

机动车车架号的检验技术

机动车车架号是车辆的原始标识符，也是表明车辆的唯一性代码，而犯罪分子使用各种手段对盗窃、走私车辆的车架号进行更改，从而达到销赃的目的。如何利用一定的方法与技术检验车架号的真伪，显现出原始车架号．是侦破机动车盗窃、走私案件的关键性技术环节，也是刑事技术领域中的一项重要工作，而关车架号检验的步骤及应该遵循原则的报道很少，因此结合近年来的实践经验，对车架号的捡验方法做归纳分析，提出捡验的步骤，并结合实例．总结出检验车架号应遵循的原则、     

伪造车辆车架号码发动机号码识别及检验

本文针对各种机动车的序号的识别及常见伪造方法、检验方法作了详细地论述。在伪造号码识别方面,对VIN码识别法、读码器识别法、痕迹检验识别法作了详细地分析描述;在原车号码复原方面,针对不同的伪造方法、不同的显现基体,应用不同的显现方法、不同的显现试剂检验方法进行了论述,简要阐述了固体显现剂的显现原理及使用方法。     

Use of Embryos Extracted from Individual Cannabis sativa Seeds for Genetic Studies and Forensic Applications

Legal limits on the psychoactive tetrahydrocannabinol (THC) content in Cannabis sativa plants have complicated genetic and forensic studies in this species. However, Cannabis seeds present very low THC levels. We developed a method for embryo extraction from seeds and an improved protocol for DNA extraction and tested this method in four hemp and six marijuana varieties. This embryo extraction method enabled the recovery of diploid embryos from individual seeds. An improved DNA extraction protocol (CTAB3) was used to obtain DNA from individual embryos at a concentration and quality similar to DNA extracted from leaves. DNA extracted from embryos was used for SSR molecular characterization in individuals from the 10 varieties. A unique molecular profile for each individual was obtained, and a clear differentiation between hemp and marijuana varieties was observed. The combined embryo extraction–DNA extraction methodology and the new highly polymorphic SSR markers facilitate genetic and forensic studies in Cannabis.     

Digital enhancement of sub-quality bitemark photographs.

Digital enhancement software was used to enhance bitemark photographs. This enhancement technique improved the resolution of the bitemark images. Lucis was the software program utilized in this study and case applications. First, this technique was applied on known bitemark images to evaluate the potential effectiveness of this digital enhancement method. Subsequently, Lucis was utilized on two separate unsolved cases involving enhancement of bitemark evidence. One case involved a severely beaten infant with a bitemark on the upper thigh. The second case involves a bitemark observed on the breast of a female sexual assault strangulation victim. In both cases, bitemark images were significantly improved after digital enhancement.     

云南大麻DNA的提取及检测初步研究

目的探讨云南大麻DNA的提取及检测方法。方法运用改进的SDS微量法提取大麻总DNA,对所得DNA进行PCR检测。结果用所筛选到的大麻引物检测了云南大麻的DNA遗传标记特征,图谱清晰,结果稳定。结论本方法能有效提取并检测大麻DNA,为实现大麻的品种鉴定、遗传多态性研究及来源追踪提供有价值的科学依据。     

Response surface methodology and improved interval analysis method-For analyzing uncertainty in accident reconstruction

Methods used to calculate intervals of accident reconstruction results are research hotspot in the word. The response surface methodology-interval analysis method (RSM-IAM) is a useful method for analyzing uncertainty of simulation results in this field, but there are two problems in this method because of the interval extension problem and inaccurate response surface models. In order to tackle these two problems, based on subinterval analysis thought and response surface methodology, an improved interval analysis method (RSM-IIAM) is proposed. In RSM-IIAM, the stepwise regression technique is used to obtain a reasonable response surface mode of the simulation model; and then, intervals of uncertain parameters are divided into several subintervals; after that, intervals of simulation results in accident reconstruction are calculated according to these subintervals. Finally, four numerical cases were given. Results showed that the RSM-IIAM is simple and high accuracy, which will be useful in analyzing uncertainty of simulation results in accident reconstruction.     

改良EVO150-8方法在DNA自动化检案中的应用

目的探讨改良EVO150-8方法在批量生物检材DNA检验中的应用价值,建立一种自动化、简单、快速的DNA提取方法。方法采用改良EVO150-8自动化核酸提取纯化仪器与DNA IQ磁珠法纯化试剂盒,对各现场提取的880份血迹、烟蒂、口香糖、精斑（混合斑）、组织、骨骼、脱落细胞等常见生物检材进行DNA提取与纯化,采用Identifiler试剂盒进行扩增检验,用3130XL电泳,GeneMapper ID V3.2分析软件进行分析比对。结果在880份生物检材中,有836份检材成功获得STR分型;检验92份检材仅需时128min。结论改良EVO150-8适合批量生物检材的自动化提取。     

Detection of copy-move forgery using a method based on blur moment invariants

In our society digital images are a powerful and widely used communication medium. They have an important impact on our life. In recent years, due to the advent of high-performance commodity hardware and improved human-computer interfaces, it has become relatively easy to create fake images. Modern, easy to use image processing software enables forgeries that are undetectable by the naked eye. In this work we propose a method to automatically detect and localize duplicated regions in digital images. The presence of duplicated regions in an image may signify a common type of forgery called copy-move forgery. The method is based on blur moment invariants, which allows successful detection of copy-move forgery, even when blur degradation, additional noise, or arbitrary contrast changes are present in the duplicated regions. These modifications are commonly used techniques to conceal traces of copy-move forgery. Our method works equally well for lossy format such as JPEG. We demonstrate our method on several images affected by copy-move forgery.     

Paternity testing by the detection of D1S80 VNTR using fluorescence image analyzer (Dualcolour system)

An improved method for DNA polymorphism typing of D1S80 VNTR locus and its application to paternity testing are described. For accurate estimation of the length of polymorphic DNA fragments, the size marker was labeled with fluorescence different from that of PCR primers, and co-electrophoresed as an internal standard. The dualcolour system of fluorescence image analyzer was used to detect the fragments and determine their size. This internal marker method could successfully overcome the problems of band pattern distortion and tailing, besides it allows easy and accurate interpretation of the DNA types. Our results indicate that the internal marker method is much more accurate than the method of using size marker in gel, even with the presence of distortion or tailing of the band patterns. Family studies applying this method showed complete agreement between the observed and predicated types.     

傅立叶变换红外光谱法检验静电复印墨粉

目的　通过对静电复印墨粉进行检验 ,达到对不同厂家及不同型号墨粉区分的目的。方法　首先利用电熨斗加热提取复印件的墨粉 ,然后利用傅立叶变换红外光谱法对 9个墨粉厂家和 2 4种牌号进行检验。结果可以达到厂家区分和大部分牌号区分 ,区分率达到 95 .7%。结论　本研究对实际应用有较大参考价值。