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91.
We studied the effects of expectation and repetition on searching for singletons in very brief displays. In Experiment 1, we found that when a given feature defined the singleton for a whole block--so that in every trial the subject could expect a particular target feature--search accuracy was significantly higher than when the feature setting was randomly redetermined from trial to trial. However, an unexpected repetition triggered almost no advantage. In Experiment 2, we found no advantage for expected alternation. Experiments 3 and 4 demonstrated that there is little or no advantage for perception in conditions allowing only for target-feature facilitation or distractor-feature inhibition. We propose that in singleton search a division of feature space facilitates detection, and that this division works best under conditions of expected repetition. Experiment 5 replicated Experiment 1, but in Experiment 5 we examined response times and long display exposures. Results suggested that previous findings of singleton priming reflect mainly postperceptual factors. 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.
94.
This paper presents a multinomial logit analysis of the methods used by Taiwanese individuals who completed suicide between 1991 and 1993. We investigated the influence of age, gender, urban or rural residence, seasons, and occupations on the six "choices" of suicide methods. The findings suggest that a systematic pattern exists between the choice of method and demographic characteristics of persons who have completed suicide. Most of the different patterns of suicide by sex, age, occupation, or residence can be understood by the different availability and accessibility to the means of suicide faced by the individuals. Our findings support Becker's (1962, 1974, 1993) contention that all kinds of human behavior or choices are shaped by the constraints imposed on the individuals. The findings also have important policy implications for suicide prevention in that they support Lester's advocacy to prevent or reduce suicide incidents by limiting availability, blocking accessibility, or "inconveniencing" the suicidal individuals. 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.
Previous researchers have proposed that there are two types of symmetry detection: one based on crude preattentive symmetry
judgments and another based on detailed scrutiny of individual parts (Barlow & Reeves, 1979; S. E. Palmer & Hemenway, 1978;
Royer, 1981). Four experiments were conducted to examine capacity limits in different symmetry judgments. Observers were required
to discriminate between random patterns and approximate symmetry (Experiments 1 and 3) or between perfect and approximate
symmetry (Experiments 2 and 4). The patterns were divided into two sets of dots, presented either simultaneously or successively.
A comparison of accuracy under these two presentation conditions suggested that symmetry detection involves an analysis that
is spatially parallel but coarse, regardless of either task difficulty or task type (detecting symmetry vs. detecting asymmetry). 相似文献
97.
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
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.
Effects of experience on fetal voice recognition 总被引:1,自引:0,他引:1
Kisilevsky BS Hains SM Lee K Xie X Huang H Ye HH Zhang K Wang Z 《Psychological science》2003,14(3):220-224
Abstract - The ability of human fetuses to recognize their own mother's voice was examined. Sixty term fetuses were assigned to one of two conditions during which they were exposed to a tape recording of their mother or a female stranger reading a passage. Voice stimuli were delivered through a loudspeaker held approximately 10 cm above the maternal abdomen and played at an average of 95 dB SPL. Each condition consisted of three 2-min periods: no stimulus, voice (mother or stranger), and no stimulus. Fetal heart rate increased in response to the mother's voice and decreased in response to the stranger's; both responses were sustained for 4 min. The finding of differential behavior in response to a familiar versus a novel voice provides evidence that experience influences fetal voice processing. It supports an epigenetic model of speech perception, presuming an interaction between genetic expression of neural development and species-specific experience. 相似文献
100.
To study maternal question-asking of Taiwanese children during free play and at meal time each mother-child dyad was videotaped at home. The mothers of children with Down syndrome asked more questions across different types of question during free play, at meal time, and for the sum of these two. Although no group difference was found for producing each type of question during free play, these 20 mothers asked more directive questions at meal time. Combined conditions analysis showed they used more directive questions and fewer requests for clarification than the 20 mothers of children with no disability. 相似文献