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This paper explores a deep-learning approach to evaluate the position of circular delimiters in cartridge case images. These delimiters define two regions of interest (ROI), corresponding to the breech face and the firing pin impressions, and are placed manually or by an image-processing algorithm. This positioning bears a significant impact on the performance of the image-matching algorithms for firearm identification, and an automated evaluation method would be beneficial to any computerized system. Our contribution consists in optimizing and training U-Net segmentation models from digital images of cartridge cases, intending to locate ROIs automatically. For the experiments, we used high-resolution 2D images from 1195 samples of cartridge cases fired by different 9MM firearms. Our results show that the segmentation models, trained on augmented data sets, exhibit a performance of 95.6% IoU (Intersection over Union) and 99.3% DC (Dice Coefficient) with a loss of 0.014 for the breech face images; and a performance of 95.9% IoU and 99.5% DC with a loss of 0.011 for the firing pin images. We observed that the natural shapes of predicted circles reduce the performance of segmentation models compared with perfect circles on ground truth masks suggesting that our method provide a more accurate segmentation of the real ROI shape. In practice, we believe that these results could be useful for firearms identification. In future work, the predictions may be used to evaluate the quality of delimiters on specimens in a database, or they could determine the region of interest on a cartridge case image.  相似文献   
43.
Various aspects of the judicial process have been hypothesized as damaging to sexual harassment plaintiffs, though limited research has been conducted that actually examines this hypothesis. We examined data from a large sample of women who participated in a class action lawsuit alleging workplace sexual harassment and discrimination (n?=?1218) and another sample of similarly situated women who opted out of litigation (n?=?465, non-litigants). We then followed the litigants for 5 years. This study takes an initial look at some of the variables theorized to play a role in the psychological outcomes of both harassment and subsequent litigation. Both the severity of harassment and participation/persistence in the litigation process were related to psychological outcomes at each of three assessments across a 5-year period; the frequency and severity of harassment, as well as plaintiffs’ cognitive appraisals of their situation, appeared to have the strongest relationship to psychological harm. Results of multivariate analysis of covariance (MANCOVA) revealed that participation and persistence in litigation played a consistent role in psychological outcomes across time, over and above the impact of harassment itself. However, litigation did not appear to be the cause of psychological outcomes as posttraumatic stress disorder (PTSD) symptomatology, in particular, was the result of the original harassment experience.  相似文献   
44.
Juvenile age estimation methods used in forensic anthropology generally lack methodological consistency and/or statistical validity. Considering this, a standard approach using nonparametric Multivariate Adaptive Regression Splines (MARS) models were tested to predict age from iliac biometric variables of male and female juveniles from Marseilles, France, aged 0–12 years. Models using unidimensional (length and width) and bidimensional iliac data (module and surface) were constructed on a training sample of 176 individuals and validated on an independent test sample of 68 individuals. Results show that MARS prediction models using iliac width, module and area give overall better and statistically valid age estimates. These models integrate punctual nonlinearities of the relationship between age and osteometric variables. By constructing valid prediction intervals whose size increases with age, MARS models take into account the normal increase of individual variability. MARS models can qualify as a practical and standardized approach for juvenile age estimation.  相似文献   
45.
Human geolocation is prefaced on the accuracy of the geographic precision of mapped isotopic values for drinking water. As most people live in cities, it becomes important to understand city water supplies and how the isotopic values uniquely reflect that city. This study investigated the isotopic distribution of δ2H and δ18O from sourced tap waters that were collected from across the Metro Vancouver (MV) area (n = 135). The results revealed that the isotopic values reflect their water sources with a range of 5.3‰ for δ18Otap and 29.3‰ for δ2Htap for MV. The results indicate that individual cities need higher resolution studies to determine their tap water isotopic ranges, and a good understanding of the water supply network itself for human geolocation work. With an extended high‐resolution understanding of each city, human tissue may be compared with more certainty for geolocation.  相似文献   
46.
The first jurisdictions in the world to introduce legislation regulating donor conception were Victoria (Australia) and Sweden in the 1980s. Under the Infertility (Medical Procedures) Act 1984 (Vic), donor-conceived people (aged 18 years and over), their parents (if children were under 18 years) and donors gained the right to apply for identifying information about each other. Information can only be given with the consent of each party. To date, over 3,500 donor-conceived children have been born in Victoria since the 1984 Victorian legislation was introduced (and enacted in 1988). The first 106 donor-conceived children under this legislation turned 18 in 2006 and many of them may not know that they are donor-conceived. The Infertility Treatment Authority, Victoria, conducted a public education campaign to provide information and support to people affected by the legislation. The campaign and services associated with donor registers have had a significant initial impact.  相似文献   
47.
Researchers and the mass media have focused increasing attention on campus crime in light of a few high-profile incidents. While rare, these incidents are important because college students are less likely to attend, spend time on, or participate in social activities on high crime campuses. The current study contributed to research on campus crime by exploring the generalizability of the updated social disorganization model to campus communities by using data collected from Peterson's Guide to Four-Year Colleges and the Uniform Crime Report for the year 2000. While social structural features of campus populations are clearly associated with rates of campus property crime, the role of social organization is less certain. These results have implications for future research and crime prevention planning on college campuses.  相似文献   
48.
Correctional scholars have suggested that research describing the world of imprisonment can help illuminate some of the consequences of incarceration, specifically how individuals experience incarceration and the ways in which these experiences effect their reentry and reintegration into society. The present study examines the perceptions, daily interactions, and relationships between prison inmates and correctional officers from the perspectives of those who have been incarcerated. Qualitative, in-depth interviews of men released from Texas prisons focus on former inmates’ personal experiences and perceptions toward correctional officers while serving time.  相似文献   
49.
A backspatter pattern results from blood drops that travel retrograde to an applied external force. Historically, an array of animals and nonhuman objects have been used to create and study backspatter patterns. In this study, backspatter patterns captured on foam core targets that were placed 45.72 cm (18 in) behind the impact site (occipital area of the skull) were produced by cranial gunshots to human cadavers that were reinfused with fresh defibrinated bovine blood. These patterns were compared to the backspatter patterns produced by shooting blood‐soaked sponges, a typical simulant used in controlled studies of backspatter pattern production and characteristics. The backspatter pattern produced by shooting an actual human head was found to be different than those of blood‐soaked sponges in the number of stains produced, the size and size range of the stains, and the stain dispersion patterns.  相似文献   
50.
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