撞击角度和速度已知条件下的球形弹丸飞行弹道轨迹算法

针对刑侦工作中弹打玻璃类案件的侦破难点,研究一种用于计算球形弹丸抛射击打玻璃案件中弹丸飞行轨迹的算法。本文以弹丸撞击角度和撞击速度为基础参数,在阐明前置基础数据的前提下,将弹打玻璃类案件中的玻璃窗分为垂直于地面及倾斜于地面两类,采用三角函数计算和参数替换的方法,通过对弹丸撞击瞬间的弹道参数设定、弹孔图像在玻璃平面内的二维图像参数设定、相关角度的描述、计算抛物线轨迹与弹道轨迹朝向等一系列步骤,最终,研究出上述两类玻璃窗的弹道轨迹计算方法。研究表明,弹丸弹道飞行轨迹算法可以还原弹丸飞行的轨迹抛物线,作为现场弹道轨迹重建系统的核心算法使用,为开发弹打玻璃类案件的现场弹道轨迹重建系统提供了关键技术。     

现代足迹检验技术实验室的建设实践与发展

足迹是案件现场出现率最高的痕迹物证,是现场勘查中发现其他物证的关键“导航仪”,在案件侦破中发挥着重要的作用。新形势下,足迹检验技术专业受限于人才培养不足、体系建设粗疏、理论研究滞后等问题,未能紧跟时代步伐,对侦查、诉讼的支撑明显弱化。2018年,公安部物证鉴定中心与重庆市公安局刑侦总队决定共建“现代足迹检验技术实验室”,希望起到以点带面的作用,实现足迹检验技术的继承创新、跨越发展。本文主要介绍实验室的规划、组织架构、战法流程和运行机制,并对利用新兴技术推动足迹检验技术发展进行展望。     

Traceology,criminalistics, and forensic science

There is a serious issue within the forensic science community, which even extends outside of the field. The role of the scientist in the investigation of crime has been increasingly confined to the laboratory, which has been accompanied by the conflation of the terms forensic science and criminalistics. This unfortunate situation has been festering for years. To make matters worse, the era of the proactive, problem-defining, criminalist (generalist) is waning, and possibly over. Present-day “criminalists” are treated as little more than reactive, protocol-constrained, laboratory technicians, with few, if any, consequential crime scene roles. In most cases, these “criminalists” merely respond to routine requests from prosecutors and police. The absence of science at the front end of forensic investigations, i.e., the scene, has resulted in biased, ineffective, inefficient, and/or erroneous outcomes with immediate and long-term societal impacts. To disentangle this imbroglio, we propose the use of another term, traceology, which has seen limited use worldwide except in the field of archaeology. With respect to criminalistics, this term has been previously proposed by Margot (20–21). Traceology is an historical science, dealing with the examination, analysis, and scientific interpretation of event traces (signs or remnants) of earlier activities. In this commentary, we define and redefine familiar, but ambiguous, terms and concepts with the hope of recapturing the essence of criminalistics (32), which we suggest is best termed traceology.