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Required 50 educable retarded children to predict their recognition accuracy when recall failed. Ss were divided into 3 ability levels: (a) old Ss (mean CA 13.25 yrs, mean MA 10.5 yrs), (b) medium Ss (mean CA 11.25 yrs, mean MA 8.75 yrs), and (c) young Ss (mean CA 9 yrs 5 mo, mean MA 6 yrs 9 mo). Results indicate that old and medium Ss could reliably predict their recognition accuracy, suggesting sensitivity to their own feeling of knowing experience, but that the young Ss showed no evidence of this sensitivity. Even though the young Ss had difficulty predicting their recognition accuracy in advance they were able to estimate the success or failure of their responses after they had occurred. Results are discussed in terms of the complexity of the metamemory judgment required, and the advisability of evaluating metamemorial knowledge across several situations is emphasized. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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As a part of a year long aerosol measurement program in the Nepal Himalayas, a series of 12 h samples of aerosol and event-based samples of precipitation were collected in postmonsoon, 1996; premonsoon, 1997; and monsoon, 1997. Results show that diurnal variations in the regional valley wind system are responsible for variations in the major ion (Na + , NH 4 + , K + , Mg 2+ , Ca 2+ , Cl - , NO 3 - , and SO 4 -2 ) concentrations in the aerosol. On time scales greater than a day, changes in atmospheric circulation and associated changes in the precipitation regime have an important effect on aerosol ion concentrations. Periods of high major ion concentration in the aerosol generally coincide with similar periods in precipitation chemistry, although a linear relationship between concentrations in these 2 media is not robust due to limited data. High scavenging ratio values are found for all species except SO 4 2- . Nitrate, Cl - , and NH 4 + are enriched in the precipitation compared to the aerosol, implying the presence of gaseous acidic species (HNO 3 and HCl) and gaseous NH 3 in the air. Ammonium was also enriched with respect to SO 4 2- in aerosol during a dry episode in the monsoon season. This may represent relatively local sources of NH 3 (from neighboring villages) and was not scavenged due to the lack of precipitation. Empirical orthogonal function (EOF) analysis clearly shows the presence of 2 dominant pollutant transport mechanisms for the premonsoon and monsoon seasons (i.e., valley wind system and monsoon circulation). Although physically different, these 2 transport mechanisms follow similar transport pathways and transport aerosol into the Himalayas from similar source regions. Further, EOF analysis suggests a southerly maritime signal in the aerosol during monsoon and a more distant westerly maritime signal during premonsoon. Our results support the potential for using glaciochemical records from the Himalayas to investigate variations in the strength of past monsoon circulation and westerly disturbances.  相似文献   
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As urban problems become more complex and as accountability and cost minimization become more of a requirement than simply a suggestion computerization is being relied upon to handle the large amounts of data upon which public administrators base decisions. Interdisciplinary teams of faculty and staff from Texas A&M University, in the areas of urban planning, computing science, industrial engineering and accounting, have been involved in studies dealing with several aspects of computerization within municipal organizations. Experience shows that the participation and support of public administrators is vital to the success of the implementation management of computerized systems.This paper develops a staged methodology useful in conducting municipal computerization studies. Investigation of the benefits and disadvantages of computerizing existing manual systems or of a major upgrade of a present computer system is performed via a four staged process. The process highlights the role of the municipal administrator, study team, potential users of the system, and the citizens.When the administrator, the study team members and the future users have a clear understanding of the goals of the system and their goals, the study has a very high chance of being successful. The Texas A&M teams use the methodology discussed here to make a concentrated effort to ensure that all parties have a part in formulating their goals and to understand their role in the design and implementation of the system.  相似文献   
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The dissolved component of the apparent silver complexation capacity was determined for Susquehanna and Chenango River water samples collected over a 3-month period in the vicinity of Binghamton, New York. Silver ion activities detected by the Ag+/S2? ion selective electrode during potentiometric titration of the river water with AgNO3 were lower than Ag+ activities calculated with an inorganic equilibrium speciation model. The maximum difference in Ag+ activity, which ranged from 1.5 × 10?8 to 8.4 × 10?8, was attributed to the presence of a constituent or constituents in the river water which strongly bind Ag, perhaps dissolved organic matter and/or colloidal material. Variation in apparent complexation capacity between river water samples was explained by different concentrations of the ligands complexing Ag. A tentative extrapolation of the dissolved Ag speciation to Ag concentrations in natural river water suggested that most of the Ag would be complexed by Cl? and an unidentified constituent or constituents.  相似文献   
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Sallie Henry  Roger Goff 《Software》1989,19(11):1065-1088
For many years the software engineering community has been attacking the software reliability problem on two fronts. First via design methodologies, languages and tools as a pre-check on complexity and secondly by measuring the complexity of produced software as a post-check. This research attempts to unify the approach to creating reliable software by providing the ability to measure the complexity of a design prior to its implementation. We have successfully defined and applied software metrics to graphical designs in an effort to predict software complexity early in the software life cycle. Metric values from the graphical design are input to predictor equations, provided in this paper, to give metric values for the resultant source code.  相似文献   
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The design and analysis of the structure of software systems has typically been based on purely qualitative grounds. In this paper we report on our positive experience with a set of quantitative measures of software structure. These metrics, based on the number of possible paths of information flow through a given component, were used to evaluate the design and implementation of a software system (the UNIX operating system kernel) which exhibits the interconnectivity of components typical of large-scale software systems. Several examples are presented which show the power of this technique in locating a variety of both design and implementation defects. Suggested repairs, which agree with the commonly accepted principles of structured design and programming, are presented. The effect of these alterations on the structure of the system and the quantitative measurements of that structure lead to a convincing validation of the utility of information flow metrics.  相似文献   
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Sallie Marston 《Cities》1985,2(2):120-123
This article examines the contemporary position of women in US urban areas. It seeks to explain the increasing numbers of service-dependent women residing in urban locations through reference to the historical evolution of the urban political economy as it reflects the national and global political economy. More specifically, it recognizes that policies at the national level influence and change urban form and function, a process which has definite and identifiable consequences for society.  相似文献   
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