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151.
In this paper we study in details a system of two weakly coupled harmonic oscillators from the point of view of Bohm’s interpretation
of quantum mechanics. This system may be viewed as a simple model for the interaction between a photon and a photodetector.
We obtain exact solutions for the general case. We then compute approximate solutions for the case where one oscillator is
initially in its first excited state (a single photon) reaching the other oscillator in its ground state (the photodetector).
The approximate solutions represent the state of both oscillators after the interaction, which is not an eigenstate of the
individual hamiltonians for each oscillator, and therefore the energies for each oscillator do not exist in the Copenhagen
interpretation of Quantum Mechanics. We use the approximate solutions that we obtained to compute Bohmian trajectories and
to study the energy transfer between the oscillators. We conclude that, even using the Bohmian view, the energy of each individual
oscillator is not well defined, as the nonlocal quantum potential is not negligible even after the coupling is turned off. 相似文献
152.
Patrice Philie 《Philosophical Studies》2007,134(2):183-210
On an internalist account of logical inference, we are warranted in drawing conclusions from accepted premises on the basis
of our knowledge of logical laws. Lewis Carroll’s regress challenges internalism by purporting to show that this kind of warrant
cannot ground the move from premises to conclusion. Carroll’s regress vindicates a repudiation of internalism and leads to
the espousal of a standpoint that regards our inferential practice as not being grounded on our knowledge of logical laws.
Such a standpoint can take two forms. One can adopt either a broadly externalist model of inference or a sceptical stance.
I will attempt, in what follows, to defend a version of internalism which is not affected by the regress. The main strategy
will be to show that externalism and scepticism are not satisfying standpoints to adopt with regard to our inferential practice,
and then to suggest an internalist alternative. 相似文献
153.
Structural equations and causation 总被引:2,自引:2,他引:0
N. Hall 《Philosophical Studies》2007,132(1):109-136
Structural equations have become increasingly popular in recent years as tools for understanding causation. But standard structural
equations approaches to causation face deep problems. The most philosophically interesting of these consists in their failure
to incorporate a distinction between default states of an object or system, and deviations therefrom. Exploring this problem,
and how to fix it, helps to illuminate the central role this distinction plays in our causal thinking.
相似文献
N. HallEmail: |
154.
Takahiro Hoshino 《Psychometrika》2007,72(4):535-549
Due to the difficulty in achieving a random assignment, a quasi-experimental or observational study design is frequently used
in the behavioral and social sciences. If a nonrandom assignment depends on the covariates, multiple group structural equation
modeling, that includes the regression function of the dependent variables on the covariates that determine the assignment,
can provide reasonable estimates under the condition of correct specification of the regression function. However, it is usually
difficult to specify the correct regression function because the dimensions of the dependent variables and covariates are
typically large. Therefore, the propensity score adjustment methods have been proposed, since they do not require the specification
of the regression function and have been applied to several applied studies. However, these methods produce biased estimates
if the assignment mechanism is incorrectly specified. In order to make a more robust inference, it would be more useful to
develop an estimation method that integrates the regression approach with the propensity score methodology. In this study
we propose a doubly robust-type estimation method for marginal multiple group structural equation modeling. This method provides a consistent estimator
if either the regression function or the assignment mechanism is correctly specified. A simulation study indicates that the
proposed estimation method is more robust than the existing methods.
This research was partially supported by the Ministry of Education, Science, Sports and Culture, Grant-in-Aid for Young Scientists
(B), 187-30406. 相似文献
155.
Dale Jacquette 《Argumentation》2007,21(4):335-347
This essay proposes and defends a general thesis concerning the nature of fallacies of reasoning. These in distinctive ways
are all said to be deductively invalid. More importantly, the most accurate, complete and charitable reconstructions of these
species and specimens of the informal fallacies are instructive with respect to the individual character of each distinct
informal fallacy. Reconstructions of the fallacies as deductive invalidities are possible in every case, if deductivism is
true, which means that in every case they should be formalizable in an expressively comprehensive formal symbolic deductive
logic. The general thesis is illustrated by a detailed examination of Walter Burleigh's paradox in his c. 1323 work, De Puritate Artis Logicae Tractatus Longior (Longer Treatise on the Purity of Logic), as a challenge to the deductive validity of hypothetical syllogism. The paradox has the form, ‹If I call you a swine, then
I call you an animal; if I call you an animal, then I speak truly; therefore, if I call you a swine, then I speak truly'.
Several solutions to the problem are considered, and the inference is exposed as an instance of the common deductive fallacy
of equivocation. 相似文献
156.
小学儿童一维空间方位传递性推理能力的发展 总被引:7,自引:2,他引:5
研究了小学儿童一维空间方位传递性推理能力的发展水平及认知策略 ,同时 ,对心理模型理论进行了检验。被试为城市中等小学 7岁、9岁、11岁儿童各 2 4名 ,男女各半。 4种实验任务分别为三前提单模型、三前提双模型、四前提单模型和四前提双模型。采用个别实验 ,儿童在前提呈现的情况下进行推理。主要研究结果 :(1)从小学 7岁到 11岁 ,儿童的一维空间方位传递性推理能力明显提高 ,7岁儿童初步形成了一维空间方位推理能力 ,9岁和 11岁基本具有了这种能力 ;(2 )随着年龄增长 ,使用模型建构策略解决问题的儿童人次越来越多 ,绝大部分 11岁儿童都能使用这一策略进行推理。但即使儿童使用了模型建构策略 ,他们的推理成绩也没有反映出模型数量所造成的任务难度差异 ,即不符合心理模型理论关于模型数量的主要预期。 相似文献
157.
Transitive performance (TP) is a learning-based behaviour exhibited by a wide range of species, where if a subject has been taught to prefer A when presented with the pair AB but to prefer B when presented with the pair BC, then the subject will also prefer A when presented with the novel pair AC. Most explanations of TP assume that subjects recognize and learn an underlying sequence from observing the training pairs. However, data from squirrel monkeys (Saimiri sciureus) and young children contradict this, showing that when three different items (a triad) are drawn from the sequence, subjects' performance degrades systematically (McGonigle and Chalmers, Nature 267:694-696, 1977; Chalmers and McGonigle, Journal of Experimental Child Psychology 37:355-377, 1984; Harris and McGonigle, The Quarterly Journal of Experimental Psychology 47B:319-348, 1994). We present here the two-tier model, the first learning model of TP which accounts for this systematic performance degradation. Our model assumes primate TP is based on a general-purpose task learning system rather than a special-purpose sequence-learning system. It supports the hypothesis of Heckers et al. (Hippocampus 14:153-162, 2004) that TP is an expression of two separate general learning elements: one for associating actions and contexts, another for prioritising associations when more than one context is present. The two-tier model also provides explanations for why phased training is important for helping subjects learn the initial training pairs and why some subjects fail to do so. It also supports the Harris and McGonigle (The Quarterly Journal of Experimental Psychology 47B:319-348, 1994) explanation of why, once the training pairs have been acquired, subjects perform transitive choice automatically on two-item diads, but not when exposed to triads from the same sequence. 相似文献
158.
Three experiments investigated whether participants used Take The Best (TTB) Configural, a fast and frugal heuristic that processes configurations of cues when making inferences concerning which of two alternatives has a higher criterion value. Participants were presented with a compound cue that was nonlinearly separable from its elements. The compound was highly valid in Experiments 1 and 2, but invalid in Experiment 3. Participants’ causal mental models were manipulated via instructions: participants were either told that cues acted through the same causal mechanism (configural causal model), through different causal mechanisms (elemental causal model), or the causal mechanisms were not specified (neutral causal model). A high percentage of participants used TTB-Configural when they had a configural causal model and a highly valid compound existed, suggesting that causal knowledge can be incorporated in otherwise very basic cognitive mechanisms to allow fine-grained adaptation to complex task structures. 相似文献
159.
Combining versus analyzing multiple causes: how domain assumptions and task context affect integration rules 总被引:1,自引:0,他引:1
Waldmann MR 《Cognitive Science》2007,31(2):233-256
In everyday life, people typically observe fragments of causal networks. From this knowledge, people infer how novel combinations of causes they may never have observed together might behave. I report on 4 experiments that address the question of how people intuitively integrate multiple causes to predict a continuously varying effect. Most theories of causal induction in psychology and statistics assume a bias toward linearity and additivity. In contrast, these experiments show that people are sensitive to cues biasing various integration rules. Causes that refer to intensive quantities (e.g., taste) or to preferences (e.g., liking) bias people toward averaging the causal influences, whereas extensive quantities (e.g., strength of a drug) lead to a tendency to add. However, the knowledge underlying these processes is fallible and unstable. Therefore, people are easily influenced by additional task-related context factors. These additional factors include the way data are presented, the difficulty of the inference task, and transfer from previous tasks. The results of the experiments provide evidence for causal model and related theories, which postulate that domain-general representations of causal knowledge are influenced by abstract domain knowledge, data-driven task factors, and processing difficulty. 相似文献
160.