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951.
F.M. Reza 《Journal of The Franklin Institute》1981,312(5):335-343
Dissipative operators appear in abundance in the study of dynamical systems. In the classical circuit theory they are presented as Positive Real Functions. The coefficients of the Taylor expansion of PRF (driving-point impedance or admittance) must satisfy certain derived inequalities. A method is suggested for obtaining restrictions of the derivative of Positive Real Functions (Dissipative Operators). 相似文献
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The purpose of this study was to examine whether scientific mobility, either between countries or between affiliations has an effect on researchers’ productivity and impact. In order to investigate this issue, we examined the relationships between the number of institutional affiliations and countries of the top 100 authors in seven disciplines. The selected authors’ profiles contained the number of affiliations and countries each author is assigned. We studied the number of affiliations and countries and compared them to three bibliometric indicators: the number of publications in international, peer-reviewed journals, h-index and Field Weighted Citations Impact. Our findings show that although there are differences in the relationship between mobility, productivity and impact between disciplines, mobility between at least two affiliations has an overall positive effect on both output and impact while mobility between countries does not. Therefore, in most disciplines positive impact and productivity effects are tracked in affiliation mobility within a single country. 相似文献
955.
C.Henry Kempe Frederic N. Silverman Brandt F. Steele William Droegemueller Henry K. Silver 《Child abuse & neglect》1985,9(2):143-154
The battered-child syndrome, a clinical condition in young children who have received serious physical abuse, is a frequent cause of permanent injury or death. The syndrome should be considered in any child exhibiting evidence of fracture of any bone, subdural hematoma, failure to thrive, soft tissue swellings or skin bruising, in any child who dies suddenly, or where the degree and type of injury is at variance with the history given regarding the occurrence of the trauma. Psychiatric factors are probably of prime importance in the pathogenesis of the disorder, but knowledge of these factors is limited. Physicians have a duty and responsibility to the child to require a full evaluation of the problem and to guarantee that no expected repetition of trauma will be permitted to occur. 相似文献
956.
11 children meeting DSM III criteria for schizophrenia (mean age approximately 12 years), a group of normal children matched in mean mental age to the schizophrenic children, and a group of younger normal children (mean age 6.6 years) were administered a series of visual information-processing tasks in order to isolate core information-processing impairments in childhood onset schizophrenia. In Experiment 1, the schizophrenic children showed impairment relative to the MA-matched normals and performed at the level of the younger normal children on a forced-choice partial-report version of the span-of-apprehension task. Previous research has shown that this task is sensitive to dysfunction in both actively and partially recovered schizophrenic adults as well as a subset of foster children at risk for schizophrenia. Experiment 2 delimited the source of the information-processing impairment in schizophrenic children by ruling out a number of possible causes of impairment and suggesting that schizophrenic children use the same information-acquisition strategies as MA-matched children but less efficiently. Experiment 3 revealed that, consistent with the previous research, the schizophrenic children were comparable with the MA-matched controls on a full-report span-of-apprehension task that placed heavy demands on iconic and short-term memory. Both the schizophrenic and MA-matched normals performed significantly better than the younger normal children. Taken collectively, the results of the three experiments suggest that all groups of children engaged in a serial information-processing strategy while performing on the partial-report version of the span-of-apprehension task. The differential impairment of the schizophrenic children on the partial-report versions but not the full-report version of the span-of-apprehension task seems to reflect inefficiencies in controlled attentional processes that normally develop during middle childhood. 相似文献
957.
POSTMODERNISM AND JAMES A. BANKS'S MULTICULTURALISM: THE LIMITS OF INTELLECTUAL HISTORY 总被引:1,自引:0,他引:1
Thomas F. Powers 《Educational theory》2002,52(2):209-221
958.
OBJECTIVES: To investigate differences and similarities between violent offenders and two types of sex offenders, rapists and child molesters, in terms of their personality, the nature of the victim, the role of alcohol, and their confession to their crime. METHOD: Thirty-six adult sex offenders, 23 child molesters, and 32 violent offenders were compared on personality measures, their relationship with the victim, the presence of alcohol intoxication, their confession rate and retraction at trial, and the reasons they gave for having confessed to the police. RESULTS: Child molesters and adult sex offenders (rapists) were significantly more introverted than the violent offenders. The child molesters had higher social desirability scores than the other groups, they tended to assault relatives and friends, they were rarely intoxicated while committing the offense, and they had strong internal need to confess to the police. Rapists and violent offenders were more commonly intoxicated during the commission of the offense; the former tended to assault acquaintances, where violent offenders most commonly assaulted strangers. Exactly half of the rapists retracted their confession when the case went to trial; in contrast none of the other offenders retracted their confession. CONCLUSIONS: The results show that there are significant differences as well as similarities between the three groups of offenders, which have implications for assessment and treatment. 相似文献
959.
Eight rhesus monkeys were trained on a counterbalanced series of concurrent, two-choice, discrimination tasks that provided different numbers of correct or incorrect objects as lists of discriminanda. Small, large, or infinite lengths of correct or incorrect object lists were combined in different tasks, and acquisition performances were compared. When tasks had an infinite number of objects in their correct list and a small number (4) in their incorrect list, acquisition entailed significantly less error than was seen when a small number of correct objects was paired with an infinite incorrect list. This pattern of outcomes seemed attributable to novelty preference. However, comparison of error distributions from tasks with infinite. list lengths to distributions from analogous tasks with fixed list lengths provided some basis for interpreting the way monkeys integrated information that emerged from the temporally discriminative properties of the tasks. One prospective concern was whether or not these performances represented behaviors like those seen in human cognitive discriminations of frequency of occurrence. 相似文献
960.