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61.
Existing NASA supported scientific databases are usually developed and managed by a team of database administrators whose main concern is the efficiency of the databases in terms of normalization and data search constructs. The populating of the database is usually done in a manual fashion by row and column as the data become available, and the data dictionary is usually defined by the same team (at times with little input from the end science user). This process is tedious, error prone and self-limiting in terms of what can be described in a relational Data Base Management System (DBMS). The next generation Earth remote sensing platforms [i.e., Earth Observing System (EOS)] will be capable of generating data at a rate of over 300 Megabits per second from a suite of instruments designed for different applications. What is needed is an innovative approach that creates object-oriented data-bases that segment, characterize, and catalog, and are manageable in a domain-specific context, and whose contents are available interactively and in near-real-time to the user community. This paper describes work in progress that utilizes an artificial neural net approach to characterize satellite imagery of undefined objects into high-level data objects. The characterized data is then dynamically allocated to an object-oriented database where it can be reviewed and accessed by a user. The definition, development, and evolution of the overall data system model are steps in the creation of an application-driven knowledge-based scientific information system. 相似文献
62.
Compared the frequency resolving power of 3 male budgerigar birds and 3 humans on several nonsimultaneous masking procedures in which one pure tone was used to mask another. Similar patterns of frequency selectivity were found for all 3 masking procedures (forward, backward, and combined forward/backward) for both species. Budgerigars showed considerably greater frequency resolving power on all 3 procedures than humans. Budgerigars also showed differences in frequency resolving power across masking conditions, but human Ss did not. Results indicate that the budgerigar auditory system may be even more highly tuned than was previously thought and suggest fundamental differences between the mechanisms of frequency selectivity of birds and humans. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
63.
We will analyze the economic sensitivity of new energy-saving technologies to weather, future energy price, and system lifetime uncertainties. Graphical rate of return analysis is employed. A representative residential solar water heating investment is analyzed to illustrate the impact of uncertainties. The wide range of reasonable rates of return found suggests some considerations for policy makers and some areas of future research. 相似文献
64.
Previous papers have demonstrated that low-cost off-peak electricity can be used to provide auxiliary heating for a passive-solar-heated residence. This paper describes the development of optimal control strategies for the operation of this auxiliary heating system. The temperature in the residence throughout the day as determined by computer simulation is presented for several optimal and conventional control strategies. The optimal control strategies improved the temperature control in the building compared to the conventional strategies. All strategies were shown to depend heavily on weather prediction. Computer simulations showed that errors in weather prediction had a small effect on heating cost and a large effect on being able to maintain the desired indoor temperature. 相似文献
65.
Anthony R. Tricker M. John Perkins Robert C. Massey David J. McWeeny 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1985,180(5):379-383
Zusammenfassung Der Gehalt an Nitrosoaminosäuren und ihr Anteil an den Gesamt-N-Nitrosoverbindungen im Fettgewebe von rohem Schinkenspeck wurde untersucht. In 80% der Proben wurde ein Gehalt an Nitrosoaminosäuren von bis zu 0,2 mg/kg festgestellt. Scheinbare Gesamt-N-Nitrosoverbindungen waren in allen Proben in einer Konzentration von 0,4 bis 3,7 mg (N-NO)/kg vorhanden. Die eigentlichen Nitrosoaminosäuren machen nur etwa 1% der scheinbaren Gesamt-N-Nitrosoverbindungen aus. Die Mehrzahl der scheinbaren Gesamt-N-Nitrosoverbindungen im Fettgewebe findet sich im nichtlöslichen Bindegewebe, wobei der verbleibende Rest chloroformlöslich ist.Summary The levels of nitrosoamino acids and apparent total N-nitroso compounds in the adipose tissue of raw bacon have been examined. Nitrosoamino acids were detected in 80% of the samples in levels of up to 0.2 mg/kg. Apparent total N-nitroso compounds were present in all samples in concentrations of between 0.4 and 3.7 mg (N-NO)/kg. Nitrosoamino acids accounted for approximately only 1 % of the apparent total N-nitroso compounds. The majority of the apparent total N-nitroso compounds in the adipose tissue were associated with the insoluble connective tissue fraction, with the remainder present as chloroform soluble species.
Einige Nitrosoaminosäuren im fettgewebe von Schinkenspeck und ihr anteil an der Konzentration der Gesamt-N-Nitrosoverbindungen相似文献
66.
Proposes a cross-cultural validation methodology that allows for the validation of French versions of English psychological scales. The 7 basic steps in the method are described: (1) preparation of a preliminary French version; (2) evaluation and modification of the preliminary version; (3) evaluation of the experimental French version in a pretest; (4) evaluation of content and concomitant validity; (5) evaluation of reliability; (6) evaluation of construct validity; and (7) preparation of norms for the French version. Examples of each step are presented. (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
Backward priming was investigated under conditions similar to those used in lexical ambiguity research. Ss received prime-target word pairs that were associated either unidirectionally (BABY-STORK) or bidirectionally (BABY-CRY). In Exp 1, targets were presented 500 ms following the onset of visual primes, and Ss made naming or lexical decision responses to the targets. Forward priming was obtained in all conditions, while backward priming occurred only with lexical decision. In Exp 2, primes were presented auditorily, either in isolation or in a sentence. Targets followed the offset of the primes either immediately or after 200 ms. Backward priming occurred with both response tasks, but only when the prime was an isolated word. Backward priming decreased over time with the naming task, but not with lexical decision. These results suggest that the locus of the backward priming effect is different for the 2 response tasks. Results support a context-independent view of lexical access. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
The current distribution and overall polarization behavior of electrodeposition at a flow-through (packed bed or fluidized bed) electrode are modeled by means of a one-dimensional model involving a primary reacting species and a simultaneous side reaction. The model equations are solved by orthogonal collocation; the time and storage requirements compare favorably to those of finite-difference methods. Experimental data obtained using a packed-bed electrode are compared with the model predictions and various methods of fitting the data are compared. 相似文献
69.
Prentky Robert A.; Knight Raymond A.; Lee Austin F. S. 《Canadian Metallurgical Quarterly》1997,65(1):141
This study examined the predictive efficacy of 10 rationally derived, archivally coded variables for assessing reoffense risk among extrafamilial child molesters. Follow-up data on 111 child molesters who were discharged from the Massachusetts Treatment Center between 1960 and 1984 were used. Degree of sexual preoccupation with children, paraphilias, and number of prior sexual offenses predicted sexual recidivism. Juvenile and adult antisocial behavior, paraphilias, and low amount of contact with children predicted nonsexual victim-involved and violent recidivism. Area under the receiver-operating characteristic curves in all three analyses indicated discrimination that was substantially better than chance, ranging from .73 to .79. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
King Abby C.; Taylor C. Barr; Haskell William L.; DeBusk Robert F. 《Canadian Metallurgical Quarterly》1989,8(3):305
Evaluated 120 healthy, sedentary, middle-aged adults randomly assigned to either a 6-mo home-based aerobic exercise training program or to an assessment-only control condition. Adherence across the 6-mo period by the exercise group was demonstrated by self-report and heart rate microprocessor methods to exceed 75%. A 14-item Likert rating scale was used to measure a variety of psychological variables. Significant between-groups differences favoring the exercise group were found on scale items closely associated with actual physical changes that occurred with exercise (satisfaction with shape/appearance, perceived fitness). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献