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以高校知识为研究和应用背景,研究基于本体理论的高校知识本体结构化表示和描述,并采用protege 4.0建立了高校知识本体。同时从高校知识中提取出基本公理、类内公理和类间公理,建立公理库,并采用protege的PAL推理引擎对高校知识进行一致性分析和推理。解决了高校知识语义层次上的信息共享和交互的问题,为高校知识的管理提供语义支撑。 相似文献
34.
Ruscio John; Walters Glenn D.; Marcus David K.; Kaczetow Walter 《Canadian Metallurgical Quarterly》2010,22(1):5
A number of recent studies have used Meehl’s (1995) taxometric method to determine empirically whether one should model assessment-related constructs as categories or dimensions. The taxometric method includes multiple data-analytic procedures designed to check the consistency of results. The goal is to differentiate between strong evidence of categorical structure, strong evidence of dimensional structure, and ambiguous evidence that suggests withholding judgment. Many taxometric consistency tests have been proposed, but their use has not been operationalized and studied rigorously. What tests should be performed, how should results be combined, and what thresholds should be applied? We present an approach to consistency testing that builds on prior work demonstrating that parallel analyses of categorical and dimensional comparison data provide an accurate index of the relative fit of competing structural models. Using a large simulation study spanning a wide range of data conditions, we examine many critical elements of this approach. The results provide empirical support for what marks the first rigorous operationalization of consistency testing. We discuss and empirically illustrate guidelines for implementing this approach and suggest avenues for future research to extend the practice of consistency testing to other techniques for modeling latent variables in the realm of psychological assessment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Bulent Akbudak 《International Journal of Food Science & Technology》2010,45(2):334-343
This study examines physicochemical changes in newly developed and existing tomato varieties at different levels of maturity. Serum viscosity is an important factor in the selection of tomato varieties for processing. Most of the attributes indicative of quality for fresh and paste tomatoes occurred at a less mature stage and declined with maturity. The canned varieties ‘H9888,’‘H8892’ and ‘H9780’ had a greater ascorbic acid content and antioxidant capacity. The highest lycopene contents were found in the varieties ‘H9888,’‘CXD254,’‘CXD222’ and ‘H9780’. Total soluble solids levels increased with maturity. The highest acidity values occurred in canned ‘Shasta’, ‘CXD254’ and ‘H9780’ varieties. Mid‐ and late‐season varieties harvested at an early stage produced thicker pastes with greater serum viscosity and acidity than tomatoes harvested at other points in the ripening process. The best results were obtained from canned samples of ‘H9888,’‘CXD254’ and ‘H9780.’ 相似文献
36.
火炮身管膛线加工的轮廓一致性保证技术 总被引:2,自引:2,他引:0
通过对火炮身管膛线加工过程的分析,提出膛线自动加工控制过程中膛线轨迹一致性保证技术,包括膛线方程数据细分归一处理方法、运动过程换向点校验修正技术、动态过程的轨迹验证。从定点采样过程数据看,整个过程Z/C联动轨迹的轮廓一致性能得到很好的保证,确保多次循环下轨迹的绝对重复。 相似文献
37.
One of the fundamental questions in personality psychology is whether and how strongly trait standing relates to the traits that people actually manifest in their behavior when faced with real pressures and real consequences of their actions. One reason this question is fundamental is the common belief that traits do not predict how individuals behave, which leads to the reasonable conclusion that traits are not important to study. However, this conclusion is surprising given that there is almost no data on the ability of traits to predict distributions of naturally occurring, representative behaviors of individuals (and that there are many studies showing that traits do indeed predict specific behaviors). The authors describe a meta-analysis of 15 experience-sampling studies, conducted over the course of 8 years, amassing over 20,000 reports of trait manifestation in behavior. Participants reported traits on typical self-report questionnaires, then described their current behavior multiple times per day for several days as the behavior was occurring. Results show that traits, contrary to expectations, were strongly predictive of individual differences in trait manifestation in behavior, predicting average levels with correlations between .42 and .56 (approaching .60 for stringently restricted studies). Several other ways of summarizing trait manifestation in behavior were also predicted from traits. These studies provide evidence that traits are powerful predictors of actual manifestation of traits in behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
38.
Badong Chen Jinchun Hu Yu Zhu Zengqi Sun 《International Journal of Adaptive Control and Signal Processing》2009,23(10):940-960
We study the problem of parameter identifiability with Kullback–Leibler information divergence (KLID) criterion. The KLID‐identifiability is defined, which can be related to many other concepts of identifiability, such as the identifiability with Fisher's information matrix criterion, identifiability with least‐squares criterion, and identifiability with spectral density criterion. We also establish a simple check criterion for the Gaussian process and derive an upper bound for the minimal identifiable horizon of Markov process. Furthermore, we define the asymptotic KLID‐identifiability and prove that, under certain constraints, the KLID‐identifiability will be a sufficient or necessary condition for the asymptotic KLID‐identifiability. The consistency problems of several parameter estimation methods are also discussed. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
39.
The multi-scale Gibbs–Helmholtz constrained (GHC) equation is a new predictive cubic equation of state that constrains the energy parameter in the SRK equation to satisfy the Gibbs–Helmholtz equation. It makes use of internal energies of departure calculated from NTP Monte Carlo simulations at the molecular length scale and a novel up-scaling expression to determine the energy parameter at the bulk phase length scale. 相似文献
40.
The (socio-)psychological concepts of individual aspiration for conformity and consistency are integrated into the rational choice framework. By using this integrative approach, it is shown that, after a shock, the aspiration for conformity results in a steady state that deviates from the homo oeconomicus's behavior toward the consumption of the peer group, whereas the aspiration for consistency leads to the result that the steady-state consumption is not reached at once. With the combination of these effects, a new consumption path is derived. After a shock, the individual consumption converges step by step to the new steady-state consumption. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献