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111.
To discriminate the acquisition pipelines of digital images, a novel scheme for the identification of natural images and computer‐generated graphics is proposed based on statistical and textural features. First, the differences between them are investigated from the view of statistics and texture, and 31 dimensions of feature are acquired for identification. Then, LIBSVM is used for the classification. Finally, the experimental results are presented. The results show that it can achieve an identification accuracy of 97.89% for computer‐generated graphics, and an identification accuracy of 97.75% for natural images. The analyses also demonstrate the proposed method has excellent performance, compared with some existing methods based only on statistical features or other features. The method has a great potential to be implemented for the identification of natural images and computer‐generated graphics.  相似文献   
112.
Leaked information, such as WikiLeaks’ Cablegate, constitutes a unique and valuable data source for researchers interested in a wide variety of policy‐oriented topics. Yet political scientists have avoided using leaked information in their research. This article argues that we can and should use leaked information as a data source in scholarly research. First, the methodological, ethical, and legal challenges related to the use of leaked information in research have been considered, concluding that none of these present serious obstacles. Second, how political scientists can use leaked information to generate novel and unique insights concerning political phenomena using a variety of quantitative and qualitative methods have been shown. Specifically, how leaked documents reveal important details concerning the Trans‐Pacific Partnership negotiations, and how leaked diplomatic cables highlight a significant disparity between the U.S. government's public attitude toward traditional knowledge and its private behavior have been demonstrated.  相似文献   
113.
This paper reports the results of four studies that investigate racial profiling as an attribution about police motives. Each study explores, first, the types of police behavior that heighten or lessen the occurrence of profiling attributions and, second, the consequences of such attributions. Results support prior studies in finding that judgments about whether the police are profiling are associated with the level of public support for the police. The studies then extend the analysis of subjective profiling judgments by examining their antecedents. The findings support the procedural justice hypothesis that the fairness with which the police exercise their authority influences whether members of the public view the police as profiling.  相似文献   
114.
This paper examines the relationship between a mother's age at first childbirth and the delinquent behavior of her children. Using data from the Rochester Youth Development Study (RYDS), an ongoing longitudinal study of adolescent development, we found that children born to mothers who began childbearing at a young age were more prone to general delinquency, violence, and arrest than were children born to mothers who began childbearing when they were older. This “early first‐birth effect” was far larger in white and Hispanic families than in African‐American families. Mediating analyses found that the early first‐birth effect was most attributable to the unstable composition of families in which early childbearing occurs. That said, a substantial portion of the effect remains unmediated.  相似文献   
115.
Extending Koons‐Witt's (2002) study of whether sex‐based disparities in imprisonment likelihoods changed under sentencing guidelines in Minnesota, we examined similar models for Ohio with additional analyses of felony conviction likelihoods and sentence length for 5,472 felony defendants from twenty‐four trial courts. The main effects of a defendant's sex on imprisonment were significant during both periods (unlike the Minnesota findings), consistent with a chivalry perspective. Random coefficient models revealed that these effects were similar across the twenty‐four jurisdictions. Analyses also revealed significant postguideline reductions in sentence length disparities based on a woman's race and number of dependent children, yet increased disparities in imprisonment likelihoods postguidelines based on a woman's race and whether she was convicted on drug charges. These and other findings are discussed in the context of the Ohio legislature's implementation of a sentencing scheme that retains considerably more judicial discretion relative to Minnesota's template.  相似文献   
116.
Studies estimate that between three and ten million children in the United States witness domestic violence annually. Although studies have demonstrated a co‐occurrence of domestic violence and child abuse, there is no concrete evidence to support the assumption that a child's exposure to domestic violence increases the risk to the child of abuse or neglect. Recently the New York State Court of Appeals determined that a child's witness to abuse does not suffice, in and of itself, to show that removal of the child is necessary or that removal is in the “best interests” of the child. Programs which have developed alternatives to presumptive removal understand the importance of viewing the interests of the battered parent and children as being in accord with each other rather than in opposition. Private and government sponsored programs have demonstrated some success in protecting the parent‐child relationship, ensuring the safety of both parent and child, and increasing accountability of batterers while reducing the necessity for removals. Alternative programs are less costly to the state than foster care, and emotionally less costly to the families.  相似文献   
117.
Much of the research focusing on conventional occupations concludes that mentored individuals are more successful in their careers than those who are not mentored. Early research in criminology made a similar claim. Yet contemporary criminology has all but ignored mentors. We investigate this oversight, drawing on Sutherland's insights on tutelage and criminal maturation and incorporating ideas on human and social capital. We argue that mentors play a key role in their protégés' criminal achievements and examine this hypothesis with data from a recent survey of incarcerated adult male offenders in the Canadian province of Quebec. In this sample, a substantial proportion of respondents reported the presence of an influential individual in their lives who introduced them to a criminal milieu and whom they explicitly regarded as a mentor. After studying the attributes of offenders and their mentors, we develop a causal framework that positions criminal mentor presence within a pathway that leads to greater benefits and lower costs from crime.  相似文献   
118.
Research on self‐control theory consistently supports its central prediction that low self‐control significantly affects crime. The theory includes other predictions, however, that have received far less scrutiny. Among these is the argument that self‐control is developed early in childhood and that individual differences emerging then persist over time. The purpose of this study is to provide a rigorous test of the stability thesis. First, we examine the extent of stability and change in self‐control for a national sample of U.S. children age 7 to age 15. Second, we consider whether parenting continues to affect self‐control during adolescence—a period after the point at which self‐control differences should be fixed. The analysis revealed strong absolute and relative stability of self‐control for more than 80 percent of the sample, and this stability emerged in large part as early as age 7. Contradicting the theory was a smaller portion of respondents (roughly 16 percent) who experienced substantial absolute and relative changes in self‐control even after the age of 10. Moreover, parental socialization continued to affect self‐control during adolescence, even after accounting for both prior self‐control and exposure to parental socialization.  相似文献   
119.
Using micro-X-ray fluorescence (MXRF), a novel means of detecting fingerprints was examined in which the prints were imaged based on their elemental composition. MXRF is a nondestructive technique. Although this method requires a priori knowledge about the approximate location of a print, it offers a new and complementary means for detecting fingerprints that are also left pristine for further analysis (including potential DNA extraction) or archiving purposes. Sebaceous fingerprints and those made after perspiring were detected based on elements such as potassium and chlorine present in the print residue. Unique prints were also detected including those containing lotion, saliva, banana, or sunscreen. This proof-of-concept study demonstrates the potential for visualizing fingerprints by MXRF on surfaces that can be problematic using current methods.  相似文献   
120.
Child-sized pig carcasses (Sus scrofa) were placed in surface deposit and buried scenarios in a wooded area of Virginia from May 1998 through December 2000, to examine the taphonomic effects of decompositional changes, predator scavenging, and the extent of remains scattering. Changes were observed through on-site examination, charting of remains, and recorded video imaging. Analysis of data revealed that utilization of corpses as food sources by vertebrates was dependent upon invertebrate colonization. Vertebrates avoided feeding on the corpses while invertebrate colonization was active, and would feed before invertebrates successfully colonized a corpse, or would wait until the invertebrate populations migrated away from the corpse. Among vertebrates, there was no apparent succession order for the animals utilizing the remains as a food source. Different vertebrates would feed at different times based upon diurnal or nocturnal predilection. Analysis noted an accidental cooperative relationship between the invertebrates and vertebrates scavenging on the corpses. Certain vertebrates gained access to the internal tissues by utilizing openings in the corpses caused by invertebrate and other vertebrate scavenging. Alternately, carrion-frequenting insects were afforded access to previously inaccessible colonization sites as a result of scavenging vertebrate activities.  相似文献   
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