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1.
Techniques of 2D–3D superimposition are widely used in cases of personal identification from video surveillance systems. However, the progressive improvement of 3D image acquisition technology will enable operators to perform also 3D–3D facial superimposition. This study aims at analyzing the possible applications of 3D–3D superimposition to personal identification, although from a theoretical point of view. Twenty subjects underwent a facial 3D scan by stereophotogrammetry twice at different time periods. Scans were superimposed two by two according to nine landmarks, and root‐mean‐square (RMS) value of point‐to‐point distances was calculated. When the two superimposed models belonged to the same individual, RMS value was 2.10 mm, while it was 4.47 mm in mismatches with a statistically significant difference (p < 0.0001). This experiment shows the potential of 3D–3D superimposition: Further studies are needed to ascertain technical limits which may occur in practice and to improve methods useful in the forensic practice.  相似文献   

2.
This study assessed the speed of recognition of facial emotional expressions (happy and angry) as a function of violent media consumption. Color photos of calm facial expressions morphed to either an angry or a happy facial expression. Participants were asked to make a speeded identification of the emotion (happiness or anger) during the morph. Results indicated that, independent of trait aggressiveness, participants high in violent media consumption responded slower to depictions of happiness and faster to depictions of anger than participants low in violent media consumption. Implications of these findings are discussed with respect to current models of aggressive behavior.  相似文献   

3.
Studies focused on facial development during childhood have been conducted by means of 3D technology to provide modifications of anthropometric parameters. Facial mobility was also considered. This study proposed a 3D approach to facial growth changes. Facial surface data of 6 subjects were acquired in T1 (age 7–14 years) and after 7 years (T2), in rest position, and during voluntary movements, by a 3D laser scanner. Linear and angular measurements on rest position scans at T1 and T2 were compared. Each mimic scan was superimposed with the corresponding rest scan. Displacement of significant anthropometric points was measured for each facial gesture and at T1 and T2 statistically compared. Vertical measurements were those most influenced by aging. Some measurements of central facial area were consistent over time. The pattern of soft tissues displacement for each expression was consistent in T1 and T2. These results may be helpful for missing children identification.  相似文献   

4.
This study presents Anthropological Facial Approximation in Three Dimensions (AFA3D), a new computerized method for estimating face shape based on computed tomography (CT) scans of 500 French individuals. Facial soft tissue depths are estimated based on age, sex, corpulence, and craniometrics, and projected using reference planes to obtain the global facial appearance. Position and shape of the eyes, nose, mouth, and ears are inferred from cranial landmarks through geometric morphometrics. The 100 estimated cutaneous landmarks are then used to warp a generic face to the target facial approximation. A validation by re‐sampling on a subsample demonstrated an average accuracy of c. 4 mm for the overall face. The resulting approximation is an objective probable facial shape, but is also synthetic (i.e., without texture), and therefore needs to be enhanced artistically prior to its use in forensic cases. AFA3D, integrated in the TIVMI software, is available freely for further testing.  相似文献   

5.
Forensic facial approximation is an auxiliary method for human identification and allows facial recognition. The midface, that includes the nose, is vital for the recognition of a familiar face. The purpose of this study was to set hard tissue parameters to estimate nasal width, to test the method to estimate nasal width of Brazilians, and to analyze the relationship between nasal profile and facial type. A total of 246 computed tomography scans (183 females and 63 males) of adults were analyzed in Horos. Bone tissue measurements and facial type classification were performed on the skull scan. Nasal profile morphology was accessed through the tool 3D surface rendering. There was a difference around 3 mm from real to predicted nose through the method to estimate nasal width in Brazilians. So, the method may be used in forensic practice. Straight nose was associated with long face type.  相似文献   

6.
The utilization of 3D computerized systems has allowed more effective procedures for forensic facial reconstruction. Three 3D computerized facial reconstructions were produced using skull models from live adult Korean subjects to assess facial morphology prediction accuracy. The 3D skeletal and facial data were recorded from the subjects in an upright position using a cone-beam CT scanner. Shell-to-shell deviation maps were created using 3D surface comparison software, and the deviation errors between the reconstructed and target faces were measured. Results showed that 54%, 65%, and 77% of the three facial reconstruction surfaces had <2.5 mm of error when compared to the relevant target face. The average error for each reconstruction was -0.46 mm (SD = 2.81) for A, -0.31 mm (SD = 2.40) for B, and -0.49 mm (SD = 2.16) for C. The facial features of the reconstructions demonstrated good levels of accuracy compared to the target faces.  相似文献   

7.
This study verified the difference between two methods of forensic facial approximation (FFA) regarding recognition and resemblance rates. Three‐dimensional models of skulls were obtained from computerized tomography (CT) scans of two subjects (targets). Two manual FFAs were performed for each target, by applying two different guidelines for the facial structures (what we called “American method” (AM) and “Combined method” (CM)). Unfamiliar assessors evaluated the sculptures by recognition and resemblance tests. The AM was that which allowed more correct responses of recognition and higher resemblance's scores for the male target (p < 0.001). Regarding guidelines for modeling characteristics of the face, the ones that are practical and easily performed for sculptures, such as the length of the anterior nasal spine multiplied by 3 for nose prediction, may offer better results in terms of resemblance.  相似文献   

8.
Abstract: Faces are assumed to be unique, but their use in court has remained problematic as no method of comparison with known error rates has been accepted by the scientific community. Rather than relying on the assumed uniqueness of facial features, previous research has been directed at estimations of face shape frequency. Here, the influence of age, sex, and ancestry on variation was investigated. Statistical shape analysis was used to examine the necessity for sub‐divisions in forensic comparisons, using a large sample of facial images on which 30 anthropometric landmark points had been placed in 3D. Results showed a clear pattern of separation of the sexes in all age groups, and in different age groups in men. It was concluded that sub‐division of databases by sex will be necessary in forensic comparisons. Sub‐division by age may be necessary in men (although not necessarily in women), and may be necessary by ancestry.  相似文献   

9.
Photogrammetry is a three-dimensional acquisition method potentially applicable to the forensic field. This possibility requires the verification of its accuracy. In this study, 3D volumes of skulls are generated to compare the photogrammetry versus the CT scan. In order to provide eligible material to the photogrammetric software, photographs were captured at a distance of 30 cm from the skull placed on a support 1 m in height and illuminated with diffused laboratory ceiling artificial light. A Nikon Coolpix P7100 camera was used. Photographs capture common elements with the previous and the next photograph so as to allow the photogrammetric software to recognize these common points between photographs and create a 3D puzzle. The Zephyr Lite (3DFlow©) software was employed to register the 3D volume. CT-based skulls are taken as a metric reference. The photogrammetry-based skulls are then enlarged according to the measurements of some landmarks or Zygion and Zygion, the distance between end of nasal and base of nasal pyramid for frontal projection, and minimum breadth of the mandibular ramus for the right lateral projection. The accuracy of the photogrammetry is compared to that of the CT scan by measuring the 3D volumes of the skulls studied. Specific landmarks are used as reference points for the measures in both frontal and lateral views. Bland–Altman graph shows homogeneity. The mean difference (1.28 mm) indicates that the measurements taken on the photogrammetry-based skull tend to slightly overestimate compared with the measurements taken on the CT-based skull.  相似文献   

10.
This study examines facial tissue depth in Canadian Aboriginal children. Using ultrasound, measurements were taken at 19 points on the faces of 392 individuals aged 3–18 years old. The relationships between tissue thickness, age, and sex were investigated. A positive linear trend may exist between tissue thickness and age for Aboriginal females and males at multiple points. No points show significant differences in facial tissue depth between males and females aged 3–8 years old; seven points show significant differences in facial tissue depth between males and females aged 9–13 years old; and five points show significant differences in facial tissue depth between males and females aged 14–18 years old. Comparisons were made with White Americans and African Nova Scotians. These data can assist in 3‐D facial reconstructions and aid in establishing an individual's identity. Previously, no data existed for facial tissue thickness in Canadian Aboriginal populations.  相似文献   

11.
Different facial reconstruction methods rely on the average facial soft tissue thickness values provided in previous studies. Facial soft tissue thickness is influenced by the age, sex, and ethnicity of the individual. The aim of the present study was to determine facial soft tissue thickness of adult Pakistani subjects with different facial morphology. A total of 166 subjects were categorized into three skeletal classes (based on convex, straight, or concave facial profile) employing the classification system used in orthodontics. Facial soft tissue thickness was determined at ten midline points on lateral cephalograms. Significant differences in facial soft tissue thickness were present at glabella, labrale superius, stomion, and labiomentale in males and at labrale superius, labrale inferius, labiomentale, and pogonion in females among different skeletal classes. The current study suggests that the skull morphology-related variations in facial soft tissue thickness should be considered during facial reconstruction to achieve accurate results.  相似文献   

12.

Purpose

This research investigated the roles of perceivers’ facial mimicry and empathy in the emotional victim effect (EVE) – the finding that complainants tend to appear more credible when exhibiting (vs. not exhibiting) negative emotional displays during their statements. Because facial mimicry plays a key role in empathic responding, it was hypothesized that inhibiting and facilitating perceivers’ mimicry would attenuate and amplify the EVE, respectively.

Methods

Participants (= 362) in an experiment were instructed to mimic or not to mimic facial expressions (controls received no mimicry instructions) while watching a statement by an emotional or non‐emotional rape complainant. Participants rated the complainant's believability and the extent to which they experienced cognitive and affective empathy.

Results

The perceived believability of the complainant was not affected by complainant emotions, thus failing to replicate the EVE. However, the inhibition of mimicry unexpectedly reduced the perceived believability of the complainant, apparently by decreasing participants’ cognitive empathy.

Conclusions

The current findings suggest that mimicry inhibition may increase scepticism in the context of credibility assessment. This has important implications for decision‐making in legal settings and for research on the process of credibility attribution. Moreover, the failure to replicate the EVE adds to the cumulative evidence on the underlying effect size for the phenomenon.  相似文献   

13.
As a second step in our three-dimensional (3D) ultrasound research on facial tissues, orthodontic patients with available lateral cephalographs (radiographs) allowing measurements of tissues along the midline of the face were recruited for ultrasound scanning. Comparison of three points on the upper lip (A-point), chin (B-point), and nose (nasion) produced differences of varying magnitude between radiographic and ultrasound measurements, with the B-point measurement being clearly affected by head orientation. Concordance was better for A-point and best for nasion. Although extension of two-dimensional (2D) ultrasound scanning of facial tissues to 3D scanning for forensic and surgical reconstructive purposes remains a worthy goal, it must be recognized that because of the differences in technique, measurements obtained from the different visualization modalities at present vary in their comparability.  相似文献   

14.
Both lay persons and professionals believe that the emotions displayed by a child witness during disclosure of sexual abuse are a factor of importance when judging the child's credibility. Unfortunately, not all children display emotions according to expectations, leading to misjudgments, and possible miscarriage of justice. In the present study, we examined how lay people's credibility judgments were influenced by a child's displayed emotions during the disclosure of sexual abuse. Participants (n?=?119), viewed video recordings of a mock police interview of an 11-year-old child actor disclosing sexual abuse, displaying one of four emotional expressions (angry, sad, neutral, and positive). Results showed that participants were strongly influenced by the emotions displayed; in particular, the display of strong negative emotions (anger) or positive emotions during disclosure significantly reduced judged credibility. The credibility ratings predicted the participant? judgments of the defendant's guilt and the willingness to pass a guilty vote in a hypothetical trial.  相似文献   

15.
Beliefs in a Just World as a Buffer Against Anger   总被引:2,自引:0,他引:2  
Anger is the emotion typically accompanying unfairness appraisals. Belief in a just world (BJW) was expected to buffer against angry feelings because subjects high in BJW play down unfairness, justify unfairness as being self-inflicted, and avoid self-focused rumination. Three studies were run to test this hypothesis. A questionnaire study revealed that subjects who strongly endorse the belief in a personally just world are less likely to experience anger and, if they do experience such feelings, are less likely to suppress them. In two experiments, an angry, a happy, or a sad mood was induced. In the anger-evoking condition, subjects high in BJW were less angry and suffered no decrease in self-esteem compared to subjects low in BJW, who reported increased feelings of anger and decreased self-esteem. It is concluded that individuals high in BJW are better able to cope with anger-evoking situations, and that BJW can be seen as a personal resource protecting not only mental but also physical health.  相似文献   

16.
Facial approximations based on facial soft tissue depth measurement tables often utilize the arithmetic mean as a central tendency estimator. Stephan et al. (J Forensic Sci 2013;58:1439) suggest that the shorth and 75‐shormax statistics are better suited to describe the central tendency of non‐normal soft tissue depth data, while also accommodating normal distributions. The shorth, 75‐shormax, arithmetic mean, and other central tendency estimators were evaluated using a CT ‐derived facial soft tissue depth dataset. Differences between arithmetic mean and shorth mean for the tissue depths examined ranged from 0 mm to +2.3 mm (average 0.6 mm). Differences between the arithmetic mean plus one standard deviation (to approximate the same data points covered by the 75‐shormax) and 75‐shormax values ranged from ?0.8 mm to +0.7 mm (average 0.2 mm). The results of this research suggest that few practical differences exist across the central tendency point estimators for the evaluated soft tissue depth dataset.  相似文献   

17.
Most of the previous studies about nose prediction were concentrated only some landmarks of the nose. This study aimed to generate prediction equations for ten landmarks of the nose in the midline and alar regions for forensic facial approximation. The six midline landmarks were the sellion, nasion–pronasale posterior, nasion–pronasale anterior, pronasale, nasal drop, and subnasale. The four landmarks of the alar region were the alare, superior alar groove, posterior alar groove, and inferior alar groove. We used the skull landmarks in the nasal, zygomatic, and maxillary bone to predict the landmarks of the nose. Cone-beam computed tomography scans of 108 Thai subjects with normal BMI and age ranging from 21.0 to 50.9 years were obtained in a sitting position. The data were converted into three-dimensional (3-D) images of the skull and face. The Cartesian coordinates of the landmarks of the skull and nose were used to formulate the multiple regression equations. The formulated equations were tested in 24 new subjects. The mean differences in the predicted midline landmarks varied between −0.4 mm and 0.5 mm, whereas those for bilateral landmarks varied between −1.0 mm and 1.4 mm. In conclusion, the prediction equations formulated here will be beneficial for facial approximation of the nose in a Thai population.  相似文献   

18.
During forensic facial reconstruction, facial features may be predicted based on the parameters of the skull. This study evaluated the relationships between alar cartilage and piriform aperture and nose morphology and facial typology. Ninety‐six cone beam computed tomography images of Brazilian subjects (49 males and 47 females) were used in this study. OsiriX software was used to perform the following measurements: nasal width, distance between alar base insertion points, lower width of the piriform aperture, and upper width of the piriform aperture. Nasal width was associated with the lower width of the piriform aperture, sex, skeletal vertical pattern of the face, and age. The current study contributes to the improvement of forensic facial guides by identifying the relationships between the alar cartilages and characteristics of the biological profile of members of a population that has been little studied thus far.  相似文献   

19.
Abstract: Postmortem computed tomography (CT) images can show internal findings related to the cause of death, and it can be a useful method for forensic diagnosis. In this study, we scanned a ready‐made box by helical CT on 2‐mm slices in a mobile CT scanner and measured each side of the box to assess whether reconstructed images are useful for superimposition. The mean difference between the actual measurements and the measurements on the three‐dimensional (3D) reconstructed images (3D‐CT images) is 0.9 mm; we regarded it as having no effect on reconstruction for the superimposition method. Furthermore, we could get 3D‐CT images of the skull, which were consistent with the actual skull, indicating that CT images can be applied to superimposition for identification. This study suggested that postmortem CT images can be applied as superimpositions for unidentified cases, and thinner slices or cone beam CT can be a more precise tool.  相似文献   

20.
Abstract: Recently a small sampled cadaver study (n = 4) suggested that the human eyeballs are placed closer to the orbital roof and lateral orbital wall as first reported in the anatomical literature many years previously. This contrasts with central positioning of the eyeball within the orbit as advocated by the facial approximation literature. Given the limits of such small samples, this study re-examined globe position in nine new cadavers to help clarify which relationship is accurate. The results essentially confirm prior empirical findings except that the mean lateral divergences from the orbit center were found to be larger—the eyeball was found to be “displaced” 1.4 mm superiorly and 2.4 mm laterally. Medians calculated across all 13 cadavers from this study and the above-mentioned recent report refine these measurements to 1.4 and 2.3 mm respectively. Globe projection values were identical to those observed for living individuals (c. 16 mm).  相似文献   

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