青年人快速行走足底压力变化的研究

目的研究足底各区域压力分布的变化及其规律,为案件现场足迹分析提供理论基础与科学依据,促进足迹标准化与定量化检验。方法利用Footscan足底压力步态分析系统,采集15名青年人快速行走和常速行走时足底压力的数据,运用SPSS软件对两种步速下足底主要承重区域压力的分布特点作相关性分析和比较研究。结果足底各区域压力分布相关性不大,反映出压力有不同程度的改变。结论现场足迹分析时,应结合具体案情及犯罪嫌疑人的活动情况,准确把握足迹特征的变化以获得理想的分析结果。     

利用不同鞋种鞋印长度推断身高差值探究

目的研究不同鞋种的鞋印长度与赤足平面足迹长度的差值数据,为利用现场各类不同穿鞋足迹分析身高等人身特点提供科学依据,也为足迹定量化分析与检验奠定基础。方法针对犯罪现场中常见鞋种,选取不同的鞋号,采集对不同足长、身高的实验者正常行走所捺印的穿鞋样本与赤足样本,对穿鞋足迹鞋印长度与赤足足迹长度进行统计与计算。结果得出不同鞋种鞋印长度与赤足平面足迹长度的差值数据。结论应用现场穿鞋足迹分析身高等人身特点时,应针对不同的鞋种,减去相关系数,结合原有身高分析公式,综合分析身高。     

青年人赤脚正常行走跖区压力特征稳定性初探

目的探讨青年人赤脚正常行走跖区压力特征的稳定性。方法借助Novel Emed足底压力分布测量系统,经数理统计方法分析足底压力数据。结果每组压力值的标准差在15N以下的占90%,每组压力面值的标准差在3个以下的占85%。结论青年人赤脚正常行走跖区的压力特征稳定。     

从足底压力分布看步法特征的可靠性

利用比利时FootScan压力传感器,对154名年龄在18至55岁之间的健康男性赤足正常行走时的足底压力数据进行提取,以运动生理学、运动生物力学及足迹步法特征理论为基础,用数理统计学方法对足迹压力数据进行了计算分析,对步法特征形成不同时期足与承受客体相互间的作用过程和作用方式进行深入、系统、定量的研究,进而对步法特征的传统理论进行验证,阐明了对步法特征理论中未经过科学验证部分的认识,并对步法特征理论中各类特征的可靠性及特征价值进行了初步的探讨,为今后的足迹步法特征检验鉴定工作和步法特征的发展完善都提供了有力的依据。     

Footscan步态分析系统在足迹检验中的应用初探

目的 探讨对人体行走运动主要步态参数的定量化分析技术.方法 以步态分析技术与足迹检验理论和方法为基础,运用先进的Footscan足底压力步态分析系统,对154名年龄在18至55岁之间的健康男性正常行走的时间、空间和力学等主要步态参数进行检测和统计分析.结果 Footscan系统采集的数据信息客观、全面,步态参数的量化分析方便、准确.Footscan系统能为足迹检验向定量化和自动化发展提供更加可靠的手段.     

计算机技术在足迹方面的应用

利用计算机图像处理软件可以管理和处理足迹，以解决现场足迹长期保存、准确测量、快速排查等难题。首先建立计算机分类足迹库和足迹特征关键字，其次对输入的足迹进行高清晰度处理和特征关键字的准确测量，并将其存入分类足迹库，最后利用足迹特征关键字快速识别相似的足迹排除不同的足迹，并利用计算机软件强大的功能对识别的足迹进行进一步鉴定，这样就可大大提高足迹鉴定的速度和准确性。现场足迹，是罪犯进行犯罪活动时留下的比较多的痕迹，它是客观存在的，只要罪犯用脚站立、行走就会留下脚印。利用现场足迹不仅为侦察破案揭露、证实…     

Simi视频动作捕捉系统在步态识别中的应用

目的探讨人体行走运动主要步态特征参数新的提取识别方法和定量化分析技术。方法以步态分析技术与传统的足迹检验理论和方法为基础,运用先进的Simi Motion视频动作捕捉系统,对50名健康男性正常行走的步态特征参数进行识别和分析。结果提出了一种基于关节点的步态特征提取方法,得到了行走步态特征的基本参数,为步态特征定量化检验提供技术支持。结论研究表明,simi视频动作捕捉系统可以获得较精确的步态特征数据,能够满足人体步态分析的需求,进而达到人身个体识别的目的。     

我国足迹研究水平步入世界前列

只要有蛛丝马迹,就叫你难逃法网。利用计算机检验犯罪分子在现场留下的足迹,从而达到破案的目的,这在今天已经从梦想变成现实。我国从50年代起利用步法追踪和足迹检验认定人身,进入80年代以后,我国科技工作者在利用足迹进行人身认定方面,形成了诸多各有所长的“足迹动力形态检验”、“足迹定量检验”、“鞋底磨损特征检验”、“单个足迹检验”等理论和方法,这使     

立体足迹计算机自动识别系统的应用

足迹是犯罪分子在作案过程中遗留在承受客体上并能反映赤足或穿鞋袜的结构形态和人体行走动力的痕迹。在我国利用步法追踪和足迹检验认定人身起步于50年代,当时还是处于少数人掌握的经验阶段。上世纪80年代以后,在马玉林先生的步法追踪的基础上,科技工作者沿着形象特征和步法特征两条线索,使足迹检验的科学理论有了较大发展。在足迹认定人身方面,形成了诸多各有所长的检验方法。为了实现足迹检验现代化,笔者和有关部门共同研制了“立体足迹计算机自动检验系统(以下简称系统),介绍如下。1“系统”性能与功能1.1原理人体站立或行走条件下,脚掌…     

利用残缺赤足足迹推算身高

目的由于主客观条件的影响,犯罪现场中常见的足迹多为不完整的残缺足迹,如何能够有效地利用残缺足迹,对案件破获往往具有至关重要的作用。方法从残缺赤足足迹的反映形态出发,选择足迹中明显、稳定的特征点,确定特征量,通过数理统计分析,建立残缺赤足足迹推算身高的经验公式。结果在4个特征量中,跖前缘突点到跟后缘突点的距离与身高的相关性最好,跖内、外缘突点到跟后缘突点的距离与身高具有一定的相关性。结论根据现场残缺赤足足迹的反映情况,也可以近似推断嫌疑人的身高特点,为侦查提供方向。     

Two-dimensional metric comparison between dynamic bare and sock-clad footprints for its forensic implications – A pilot study

Footprints may be present at crime scenes as physical evidence. This pilot study compares two-dimensional measurements of bare and sock-clad footprints to determine if significant differences or similarities exist. Dynamic footprints were collected from 30 males and 20 females between the ages of 20 and 61?years old (mean of 28.2?years) using the Identicator Inkless Shoe Print Model LE 25P system. A midgait protocol was employed for obtaining footprints. The fifth and sixth footprint of gait were collected for the right and left foot, respectively, in both sock-clad and barefoot trials. The footprint measurements between sock-clad and bare footprints were compared. The results did not indicate any significant difference (p?>?.05) between bare and sock-clad foot length measurements for right or left feet. Significant differences were seen for the width measurements between bare and sock-clad footprints. These findings have forensic implications, particularly in criminal cases where it is unclear if a footprint impression is from a sock-clad foot or a bare foot. This study shows that such a determination is generally not necessary when utilizing two-dimensional measurements for length comparison between a bare and sock-clad footprint. However, if width measurements are being evaluated, the distinction between bare and sock-clad footprints should be considered.     

Two-dimensional linear analysis of dynamic bare footprints: A comparison of measurement techniques

In forensic intelligence-gathering, footprints have been shown to be valued evidence found at crime scenes. Forensic podiatrists and footprint examiners use a variety of techniques for measuring footprints for comparison of the crime scene evidence with the exemplar footprints. This study examines three different techniques of obtaining two-dimensional linear measurement data of dynamic bare footprints. Dynamic bare footprints were gathered from 50 students from a podiatric medical school using the Identicator® Inkless Shoe Print Model LE 25P system. After obtaining 100 bilateral footprints from the participants, the quantitative measurement data were collected by using three different measurement techniques: (i) a manual technique using a ruler (direct technique); (ii) an Adobe® Photoshop® technique; and (iii) a GIMP (GNU Image Manipulation Program) technique. The seven Reel linear measurement methodology was used for producing measurements using these three techniques.This study showed that all the mean bare footprint measurements on the right and left feet obtained using the direct technique were larger than those obtained using GIMP and Adobe® Photoshop® images. Differences were also observed in measurements produced using GIMP software and Photoshop images. However, the differences observed in the three techniques used for bare footprint measurements were not found to be statistically significant. The study concludes that there are no significant differences between the three measurement techniques when applied to two-dimensional bare footprints using the Reel method. It further concluded that any of these measurement techniques can be used when employing the Reel methodology for footprint analysis without significant difference.     

身高与足迹长度相关关系综合研究

目的全面分析研究足迹长度与身高之间的相关关系及其变化规律。方法在全国范围内大量抽样收集不同地区、不同年龄、不同性别人群的足迹样本,逐一测量其足迹长度,建立数据库,利用计算机进行综合统计、回归分析、比较研究。结果获得大量的分析数据及回归方程。结论足迹长度与身高之间的相关关系明显,可以根据足迹长度分析留痕人的身高。     

鞋内底足迹显现效果的影响因素

目的探究鞋内底足迹的显出情况及可能影响显现效果的因素,寻找有效的鞋内底足迹显现方法。方法收集PU材质的皮鞋鞋垫、EVA材质的运动鞋鞋垫、解放牌胶鞋鞋垫共144只,用多波段光源法、茚二酮法、茚三酮法三种方法分别对穿用时间为一周、一个月、三个月、六个月的鞋内底足迹进行显现,按照显现方法、材质、穿用时间进行分类讨论并对数据进行统计和分析。结果采用多波段光源法、茚二酮法、茚三酮法分别成功显出15、14、19例,有效显出率分别为31.25%、29.17%、39.58%,PU材质、EVA材质、解放牌胶鞋三种材质分别成功显出15、23、10例,有效显出率分别为31.25%、47.92%、20.83%,穿用时间为一周、一个月、三个月、六个月的检材分别成功显出3、6、13、26例,有效显出率分别为8.33%、16.67%、36.11%、72.22%。多波段光源法、茚二酮法、茚三酮法对鞋内底足迹显出率的影响,其差异无明显统计学意义;EVA材质运动鞋鞋内底足迹显出率高于PU材质皮鞋鞋内底足迹显出率,高于解放牌胶鞋鞋内底足迹显出率,并且差异具有统计学意义;穿用时间长的检材显出率高于穿用时间短的检材并且差异具有统计学意义。结论鞋内底足迹的显现效果与鞋内底材质、穿用时间因素有关,多波段光源法、茚二酮法、茚三酮法均能对鞋内底足迹有效显出。     

A statistical methodology for the comparison of blue gel pen inks analyzed by laser desorption/ionization mass spectrometry

A statistical methodology for the objective comparison of LDI-MS mass spectra of blue gel pen inks was evaluated. Thirty-three blue gel pen inks previously studied by RAMAN were analyzed directly on the paper using both positive and negative mode. The obtained mass spectra were first compared using relative areas of selected peaks using the Pearson correlation coefficient and the Euclidean distance. Intra-variability among results from one ink and inter-variability between results from different inks were compared in order to choose a differentiation threshold minimizing the rate of false negative (i.e. avoiding false differentiation of the inks). This yielded a discriminating power of up to 77% for analysis made in the negative mode. The whole mass spectra were then compared using the same methodology, allowing for a better DP in the negative mode of 92% using the Pearson correlation on standardized data. The positive mode results generally yielded a lower differential power (DP) than the negative mode due to a higher intra-variability compared to the inter-variability in the mass spectra of the ink samples.     

The Relationship between Meteorological Conditions and Homicide,Suicide, Rage,and Psychiatric Hospitalization

This study focuses on the relationship between the incidence of homicide, rage, suicide, and psychiatric hospitalization as violent behaviors with temperature, humidity, and air pressure as specific meteorological variables in the city of Mashhad, in the northeast of Iran. The data were obtained from Iran Meteorological Organization, official registry of Legal Medicine Organization and the local psychiatric hospital, March 2009 to Feb 2010 daily and were analyzed with SPSS‐14 using Pearson correlation coefficient, ANOVA, and post hoc analysis tests. The rates of rage and psychiatric admission had a significant relationship with the daily mean air temperature, minimum relative humidity, maximum relative humidity, minimum daily pressure, and maximum daily air pressure (p < 0.0001). There was no significant correlation between homicide and suicide rates with any meteorological variables (p > 0.05). We concluded that, the possibility of nonfatal violence and psychiatric hospitalization would increase in hot and arid weather with low air pressure.     

The contact area of static and dynamic footprints: Forensic implications

When found at crime scenes, footprints may be evidentially valuable and can assist with the identity of a perpetrator based on their features and/or measurements. Footprints can be either static (made while standing) or dynamic (made while walking). While extensive research has been performed on the linear measurements obtained from static and dynamic footprints, research on the comparisons between the contact area of static and dynamic footprints in the forensic context are limited. The present study compares the contact area of static and dynamic bare footprints to determine if statistically significant differences exist between the two. Static and dynamic footprints were obtained from a sample of randomly-selected 461 Jatt Sikh adults (230 males and 231 females) of Indian origin between the ages of 19 and 32 years. The footprint contact area was calculated from each footprint (excluding the toes) using a PedoGRID® sheet. No statistically significant differences were observed between the contact area of static and dynamic footprints for each foot among males and females. However, statistically significant differences between both the sexes were found in the footprint contact areas of both footprint types. The right dynamic footprint contact area was found to be the most predictive measurement for classifying and estimating sex from a footprint’s contact area. The study has implications in the analysis of footprints recovered from crime scenes.     

Shoe wear patterns and pressure distribution under feet and shoes, determined by image analysis.

A method is outlined for extracting contours of the pressure exerted by feet on the ground, either directly or through the soles of shoes, and of the wear patterns on shoe soles. The method is applied to two types of image: shoeprint images made in the laboratory, and pedobarography images recording the distribution of pressure under the foot during a footstep. The first procedure in extracting the information from images involves low pass filtering in the Fourier domain, performed by a microcomputer and frame-grabbing system. The boundaries of the regions in the resultant images are then extracted from the filtered images to display the shape of constant pressure areas and of the general shoe-wear.