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881.
Yoshino M Taniguchi M Imaizumi K Miyasaka S Tanijiri T Yano H David C Thomas L Clement JG 《Forensic science international》2005,148(2-3):113-120
A new retrieval system for a 3D facial image database was designed and its reliability was experimentally examined. This system has two steps, firstly to automatically adjust the orientation of all 3D facial images in a database to that of the 2D facial image of a target person, and then to identify the facial image of the target person from the adjusted 3D facial images in the database using a graph-matching method. From the experimental study [M. Yoshino, K. Imaizumi, T. Tanijiri, J.G. Clement, Automatic adjustment of facial orientation in 3D face image database, Jpn. J. Sci. Tech. Iden. 8 (2003) 41-47], it is concluded that the software developed for the first step will be applicable to the automatic adjustment of facial orientation in the 3D facial image database. In 28 out of 110 sets (25.5%), the 3D image of the target person was chosen as the best match (from a database of 132 3D facial images) according to the similarity of the facial image characteristics based on the graph matching. The 3D facial image of the target person was ranked in the top of 10 of the database in 75 out of 110 sets (68.2%). These results suggest that this system is inadequate for the identification level, but may be feasible for screening method in a small database. It will be necessary to further pursue the possibility of realization of a facial image retrieval system for a large database such as suspects' facial images in future. 相似文献
882.
Salas A Prieto L Montesino M Albarrán C Arroyo E Paredes-Herrera MR Di Lonardo AM Doutremepuich C Fernández-Fernández I de la Vega AG Alves C López CM López-Soto M Lorente JA Picornell A Espinheira RM Hernández A Palacio AM Espinoza M Yunis JJ Pérez-Lezaun A Pestano JJ Carril JC Corach D Vide MC Alvarez-Iglesias V Pinheiro MF Whittle MR Brehm A Gómez J 《Forensic science international》2005,150(2-3):191-198
A qualitative and quantitative analytical method was developed and validated for the determination of 49 licit and illicit drugs in oral fluid. Small oral fluid samples, volume 1mL, were collected from volunteers using a modified Omni-Sal device and the analytes were extracted from an oral fluid/buffer mixture using a single Bond Elut Certify solid phase extraction cartridge. Liquid chromatography-tandem mass spectrometry (LC-MS-MS) and gas chromatography-repetitive full scan mass spectrometry (GC-MS) were used in parallel to analyze the extracts for the targeted drugs. Extracts were analyzed by GC-MS in their underivatized form and as their pentafluoropropionyl derivatives. Deuterated internal standards were used for quantification of drugs of abuse by LC-MS-MS to minimize matrix effects. Methadone-d(9) and tumoxetine were used as the internal standards for quantification of non-derivatized and derivatized analytes respectively by GC-MS. Linearity was demonstrated over the range 5-200 ng/mL and limits of detection were less than 4 ng/mL for each drug analyzed. The method demonstrated acceptable recoveries for most of the analytes and good intra- and inter-day precision. Acquisition of data by repetitive full scan GC-MS allows the addition of further analytes to the target menu. 相似文献
883.
The capacity of police departments to solve crimes and apprehend offenders is low for many types of crime, particularly crimes of profit. This article reviews a variety of studies of police apprehension and hypothesizes that an important determinant of the ability of the police to apprehend criminals is information. The complete absence of information for many types of crime places fairly clear upper bounds on the ability of the police to effect solutions.To discover whether these boundaries are high or low we analyzed data from the 1973 National Crime Panel about the types and amount of information potentially available to police through victim reports and patrol activities. The evidence suggests that if the police rely on information made readily available to them, they will never do much better than they are doing now. On the other hand, there appears to be more information available to bystanders and passing patrols than currently is being used, which suggests that surveillance strategies and improved police methods for eliciting, recording, and analyzing information supplied by victims and witnesses might increase the probability of solving crimes and making arrests. In light of this we review a few possibly helpful innovations suggested in the literature on police productivity and procedure. 相似文献
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The technique of isoelectric focusing in ultra-thin polyacrylamide gels as a method of typing human red cell phosphoglucomutase (PGM1) has been studied. Typing was possible without the samples attaining true equilibrium focusing conditions. The isozyme patterns so obtained were clearly defined and free from distortion. The importance of assessing relative band intensities when interpreting the isozyme patterns is discussed. Our experience of using the technique to analyse casework material is described. 相似文献
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