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91.
Texture gradients can reveal surface orientation in a manner similar to shape from shading, and therefore provide an important cue for object recognition. In this study, we tested whether a complex 3-D object, such as a face, can be identified from texture gradients alone. The stimuli were laser-scanned faces for which the texture element was a fractal-noise pattern mapped onto the 3-D surface. An eight-alternative forced choice task was used in which participants matched a face defined by texture gradients to one of eight faces defined by shape from shading (Experiment 1) or by texture gradients (Experiment 2). On average, participants scored 24% and 18%, respectively, above chance in these experiments. Although this performance was much poorer than the performance based entirely on shape-from-shading stimuli (Experiment 3), the results suggest that texture gradient information may be used to recover surface geometry of complex objects. 相似文献
92.
Matthew Hoffman 《Jewish History》2005,19(1):65-78
The Russian Jewish intellectual, Chaim Zhitlovsky (1865–1943), a leading architect of secular Jewish culture and thought, was a central figure in the progressive Jewish intelligentsia of the late nineteenth and early twentieth century. In an essay written in 1927, Yidn un Yiddishkayt (Jews and Jewishness), he sought to define the secular essence of what he calls Yiddishkayt. This essay is not the first in Zhitlovskys long publicistic career in which he searches for new, secular definitions of Jewish identity and culture. But this essay differs, since it is marked by Zhitlovskys use of contemporary social scientific notions of race and racial traits to conceptualize what he believes constitutes Jewishness in a non-religious context, along with his adoption of the mystical Jewish concept of the pintele yid, the theory of an innate Jewishness embodied by a Jewish spark. Zhitlovskys desire to craft a truly secular theory of Jewish identity led him ironically to accept models of Jewish identity at odds with his stated larger vision. In turning to contemporary racial theory, as well as long nurtured mystical models of Yiddishkayt, Zhitlovsky reveals the wide range of ideological discourses that led him to innovative and controversial notions of modern Jewish identity. 相似文献
93.
晏婴以极忠尽谏闻名,而其劝谏的主要内容便是要齐君效法古之贤君爱民、重民,体现出中国传统文化中的民本思想.本文以《晏子春秋》为据,描述晏婴的谏诤形象和高超的进谏艺术与技巧. 相似文献
94.
Ran MS Xiang MZ Mao WJ Hou ZJ Tang MN Chen EY Chan CL Yip PS Conwell Y 《Suicide & life-threatening behavior》2005,35(6):694-701
In this study, demographic and clinical characteristics of individuals with schizophrenia in a Chinese rural community who had attempted suicide at some time in their lives and those who had not made a suicide attempt were compared. Among individuals with schizophrenia, subjects with (n = 38) and without (n = 472) a lifetime history of suicide attempt were assessed with the Present State Examination. The results indicate that attempters had a significantly younger age, higher level of education, higher rate of lifetime depressed mood and hopelessness, and a larger number of positive symptoms than patients without suicide attempts. The logistic regression models also indicated that hopelessness, the number of positive symptoms and age were the most important predictors. Early interventions focusing on reducing hopelessness and controlling positive symptoms may help reduce the risk of suicide attempts among patients with schizophrenia. 相似文献
95.
Throughout the U.S., state laws require professionals who work with children to report cases of suspected child abuse to child protection services. Both practically and conceptually, however, significant problems arise from a lack of clarity regarding the threshold that has been set for reporting. Specifically, there is no consensus as to what constitutes reasonable suspicion, and little direction for how mandated reporters should gauge their legal and professional responsibilities when they harbor suspicion. In this paper we outline the context of the problem, discuss the nature and scope of its conceptual underpinnings, and offer recommendations for moving towards a concrete, practical solution. 相似文献
96.
Catalano GD 《Science and engineering ethics》2004,10(2):409-415
A senior level capstone design experience has been developed and offered with a particular emphasis on many of the professional
issues raised in Accreditation Board for Engineering and Technology (ABET) Engineering Criterion IV. The course has sought
to develop student awareness of the ethical foundation of the engineering profession, the global and societal framework within
which engineers practice, and the environmental impact on engineering. The capstone design course also focused upon improving
the technical communications skills of the graduating senior class with both extensive instruction in writing and multiple
workshops dealing with the art of making an effective oral presentation. The effectiveness of the design course was assessed
using Kirkpatrick’s model for evaluating training programs.
An earlier version of this paper was presented at the “Ethics and Social Responsibility in Engineering and Technology” meeting,
New Orleans, 2003. 相似文献
97.
By regarding the latent random vectors as hypothetical missing data and based on the conditional expectation of the complete-data
log-likelihood function in the EM algorithm, we investigate assessment of local influence of various perturbation schemes
in a nonlinear structural equation model. The basic building blocks of local influence analysis are computed via observations
of the latent variables generated by the Metropolis-Hastings algorithm, while the diagnostic measures are obtained via the
conformal normal curvature. Seven perturbation schemes, including some perturbation schemes on latent vectors, are investigated.
The proposed procedure is illustrated by a simulation study and a real example.
Acknowledgment: This research is fully supported by a grant (CUHK 4243/02H) from the Research Grant Council of the Hong Kong
Special Administration Region. The authors are indebted to ICPSR and the relevant funding agency for allowing use of their
data, and to the Editor and reviewers for their valuable comments for improving the paper. 相似文献
98.
Faculty members at Canadian business schools were surveyed regarding their ethical perceptions of behaviours related to undergraduate instruction. Fifty-five behavioural statements were listed and respondents were asked to rate the extent to which they felt each behaviour was ethical or unethical. The only item that respondents endorsed as unequivocally unethical (90% indicated it was definitely unethical) was Becoming sexually involved with an undergraduate in one of your classes. We also compared the results of our sample to those of an American sample. Overall, an interesting pattern of differences emerged between the responses obtained in Canada and the U.S. In general, the direction of the significant differences was such that Canadian professors viewed the behaviours in question as less ethical than did their American counterparts. 相似文献
99.
Hong YY Chan G Chiu CY Wong RY Hansen IG Lee SL Tong YY Fu HY 《Journal of personality and social psychology》2003,85(6):1147-1160
Social identity approaches assume that social identification affects both self-conception and intergroup orientation. The authors contend that such social identification effects are accentuated when people hold a fixed view of human character and attribute immutable dispositions to social groups. To these individuals, social identities are immutable, concrete entities capable of guiding self-conception and intergroup orientation. Social identification effects are attenuated when people hold a malleable view of human character and thus do not view social identities as fixed, concrete entities. The authors tested and found support for this contention in three studies that were conducted in the context of the Hong Kong 1997 political transition, and discussed the findings in terms of their implications for self-conceptions and the meaning of social identification. 相似文献
100.
Yu H Russell DM Sternad D 《Journal of experimental psychology. Human perception and performance》2003,29(3):616-630
Variability in rhythmic movements has been interpreted as a signature of internal or peripheral noise processes. Grounded in an oscillator interpretation, this study hypothesized that period variability and drift arises from the asymmetry between target period and the limb's intrinsic dynamics. Participants synchronized to 7 target periods, swinging 1 of 3 pendulums in a continuation paradigm; 3 periods were longer, 3 shorter, and 1 identical to the preferred period. Results supported 5 predictions: Drift toward the preferred period was observed that scaled with the asymmetry. Variability was lowest for symmetry conditions and increased with the asymmetry. Variability decreased concomitant with the approach toward the preferred period. Periods exponentially approached the preferred period with positive autocorrelations up to 10 cycles. 相似文献