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981.
Heat transfer in laminar tube flow with convective boundary conditions and axial heat conduction in the fluid is solved exactly. The effects of the external Biot numbers and the axial conduction in fluid on the temperature distribution and the local Nusselt number are determined for both the upstream and the downstream regions. In order to illustrate the effects of velocity profile, the results for the slug flow and the parabolic velocity profiles are plotted simultaneously. The heat transfer characteristics of the flow are found to be rather sensitive to the Péclét number, the external Biot numbers and the velocity profile in the thermal entrance region.  相似文献   
982.
983.
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   
984.
985.
986.
ABSTRACT

Blogging has been associated with the Library and Information Science (LIS) community for some time now. Libfocus.com is an online blog that was founded in 2011. Its goal was to create a communal communication space for LIS professionals in Ireland and beyond, to share and discuss issues and ideas. The content of the blog is curated by an editorial team and features guest bloggers from across all sectors and experience levels. Using a qualitative methodological approach, open-ended surveys were conducted with twelve previous guest bloggers, in order to explore how and why Irish-based LIS professionals choose to communicate through blogging. It is hoped that this evidence will provide a greater understanding of both the value and effectiveness of blogging as an outreach and communication tool within the profession, helping both libraries and librarians to be more strategic in their use of it as a medium.  相似文献   
987.
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   
988.
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   
989.
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   
990.
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