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941.
In this paper, silt sediment is considered to be Bingham body, which is made up of coarse and fine particles in front of a hydraulic gate. The coarse and fine particles provide friction and shear stress in the course of opening the gate. They constitute together the adhesion force of the sediment. Based on this viewpoint, this paper puts forward a formula for the effect of silt sediment on the lifting force. The formula includes gate weight, down-suction force, sealing rubber friction, plus-weight, water-column pressure, plus-silted-sediment weight and rolling (or sliding)-bearing friction. Finally, the verification results show that the formula has certain reliability and the calculation accuracy can meet the need of practical engineering. 相似文献
942.
A neuro-space mapping(Neuro-SM) for modeling heterojunction bipolar transistor(HBT) is presented, which can automatically modify the input signals of the given model by neural network. The novel Neuro-SM formulations for DC and small-signal simulation are proposed to obtain the mapping network. Simulation results show that the errors between Neuro-SM models and the accurate data are less than 1%, demonstrating that the accurcy of the proposed method is higher than those of the existing models. 相似文献
943.
The Bacillus strain BH072 isolated from a honey sample showed strong antifungal activity against phytopathogen. Gene cloning test demonstrated that the strain had a tasA gene encoding an antifungal TasA protein. Although the wild strain simultaneously produced various antifungal substances, only the physicochemical property and antifungal activity of TasA protein were unclear due to the difficulty in extraction. In this study, tasA gene encoding the protein from Bacillus sp. BH072 was amplified by using the polymerase chain reaction (PCR) method and cloned into pET 28a (+) vector, and then expressed in host cells Escherichia coli BL21 (DE3). The expressed proteins were collected by centrifugation and ultrasonic treatment, and then purified by using nickel-nitrilotriacetic acid (Ni-NTA) metal affinity column and dialysis methods. The result of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) test showed that an expected protein band appeared with a size of 31 kDa. The expressed products possessed antifungal activity against the phytopathogenic indicator strain Botrytis cinerea. A genetically engineered strain tasA of E. coli was established in this study which can efficiently express Tas A protein. 相似文献
944.
Jennifer Bragger Eugene J. Kutcher Gaynell Schettino Bridget Muzyczyn Pamela Farago Emily Fritzky 《Performance Improvement Quarterly》2016,29(2):97-124
Structuring job interviews is a method of decreasing bias and increasing the predictive validity of job performance, but research suggests that applicants can react negatively to structure (Chapman & Zweig, 2005) and that negative attitudes about selection tools can predict performance (Hausknecht, Day, & Thomas, 2004). The current exploratory study investigates how structuring the job interview in conjunction with priming the ethnicity and sex of the applicant, and in some conditions providing an explanation of the structure, affected post‐interview cognitive ability performance. Three levels of structure were randomly assigned. Those who experienced a structured interview without an explanation of its purpose scored lower than those who experienced an unstructured interview, but those who experienced a structured interview with an explanation of its purpose did not score lower than those who experienced an unstructured interview. Scores differed for females and Hispanics depending on the structure condition, but not in the same manner. Implications for recruitment, selection, and performance management are discussed. 相似文献
945.
Scott D. Anderson 《Performance Improvement》2016,55(10):27-31
The candidate chooses projects for his or her ability to establish credentials as a performance technologist. The clearer the links between actions and improved performance for the client, the stronger the case each example makes. Candidates will need to show this linkage between contribution and outcome for each project used in preparing the submission package. 相似文献
946.
Family Income Dynamics,Early Childhood Education and Care,and Early Child Behavior Problems in Norway
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The sociopolitical context of Norway includes low poverty rates and universal access to subsidized and regulated Early Childhood Education and Care (ECEC). In this context, the association between family income dynamics and changes in early child behavior problems was investigated, as well as whether high‐quality ECEC buffers children from the effects of income dynamics. In a population‐based sample (N = 75,296), within‐family changes in income‐to‐needs predicted changes in externalizing and internalizing problems (from ages 18 to 36 months), particularly for lower income children. For internalizing problems, ECEC buffered the effect of income‐to‐needs changes. These findings lend further support to the potential benefits of ECEC for children from lower income families. 相似文献
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949.
Relationship Reciprocation Modulates Resource Allocation in Adolescent Social Networks: Developmental Effects
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Stephanie Burnett Heyes Yeou‐Rong Jih Per Block Chii‐Fen Hiu Emily A. Holmes Jennifer Y. F. Lau 《Child development》2015,86(5):1489-1506
Adolescence is characterized as a period of social reorientation toward peer relationships, entailing the emergence of sophisticated social abilities. Two studies (Study 1: N = 42, ages 13–17; Study 2: N = 81, ages 13–16) investigated age group differences in the impact of relationship reciprocation within school‐based social networks on an experimental measure of cooperation behavior. Results suggest development between mid‐ and late adolescence in the extent to which reciprocation of social ties predicted resource allocation. With increasing age group, investment decisions increasingly reflected the degree to which peers reciprocated feelings of friendship. This result may reflect social‐cognitive development, which could facilitate the ability to navigate an increasingly complex social world in adolescence and promote positive and enduring relationships into adulthood. 相似文献
950.