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61.
Two models of second-order ZFC need not be isomorphic to each other, but at least one is isomorphic to an initial segment of the other. The situation is subtler for impure set theory, but Vann McGee has recently proved a categoricity result for second-order ZFCU plus the axiom that the urelements form a set. Two models of this theory with the same universe of discourse need not be isomorphic to each other, but the pure sets of one are isomorphic to the pure sets of the other.This paper argues that similar results obtain for considerably weaker second-order axiomatizations of impure set theory that are in line with two different conceptions of set, the iterative conception and the limitation of size doctrine. 相似文献
62.
The point of scientificity, or pos,represents a place in history whereeducational administration was founded as ascience. A pos creates a field of memoryand a field of studies. A pos isepistemologically sustained in its claim forscientific status by a line of demarcation orlod. A lod is supported by truthclaims based on various forms ofcorrespondence. As these forms have beeninterrogated and abandoned, correspondence hasgiven way to coherentism and finally to testsof falsification. As falsification has shownto contain serious flaws when compared to theactual history of scientific discoveries, theentire project of a distinct and unitaryfield known as educational administration isseriously cast into doubt. Contemporaryexaminations in educational administrationdiscourse show that even when the lod hasbeen undermined by epistemological shifts, theinitial pos has remained to supportclaims regarding the project of a ``science ofleadership.' The analysis contained in thisarticle show, however, that when claims of thelod are demonstrably unsustainable, theinitial pos must be similarly abandoned. With that collapse the concept of a fieldis likewise effaced. The epistemologicalalternative is to envision fields ofstudy which do not require a lod, excepton a longitudinal basis to ascertain whether aresearch program shaped and sustained by it isprogressive or regressive. In short, there areno aprori meta-criteria to separate sciencefrom non-science in educationaladministration. 相似文献
63.
本研究中运用了两个实验探讨数数干预和测查条件对儿童在集合比较中运用数数的影响。干预对3岁儿童(M=3:9)没有影响。在平均年龄为4岁4个月时.干预组儿童比控制组儿童更倾向于用数数比较集合.自然组儿童也比传统组更倾向于用数数。许多4岁儿童在无干预时不用数数可能是因为,1)不知数数比视觉性比较更有效,或2)他们在集合比较中的数数极易受测查情景因素的影响。儿童在集合比较中的数数运用与他们的数数水平密切关联。 相似文献
64.
We are concerned here with the existential question: In order to live a virtuous life, whether it is better to commit one's life to good works among humankind or to the perfection of one's spiritual being by turning away from humanity and devoting oneself entirely to God. We examine this issue—a controversy in moral philosophy from the time of the ancient Greeks—in a short story by Leo Tolstoy. 相似文献
65.
The key aim of the present research was to study the “functionality” of two global variables in the Olweus Bully/Victim Questionnaire and to examine the appropriateness of different cutoff points of these variables for prevalence estimation. Several empirical and conceptual analyses strongly attested to the functionality of the two selected variables in terms of construct validity and selected measurement properties. Similarly, a number of analyses indicated that (having been bullied/having bullied other students) “2 or 3 times a month” was a reasonable and useful lower‐bound cutoff point. With this cutoff point, “involved” students, victims, and bullies differed very markedly and in clearly different ways from “non‐involved” students in conceptually related variables. Prevalence estimates derived in this way can be conveniently obtained, have a reasonably well‐defined meaning, can be easily understood by users, and can be reproduced unambiguously by different researchers/administrators and at different times. An important background for the article is the fact that several common methods, including peer nominations, are not well suited for prevalence estimation. Prevalence data for victims, bullies, and bully‐victims are also presented. All data were derived from the New Bergen Project Against Bullying, comprising a sample of 5,171 students from 37 schools in the town community of Bergen, Norway. At the time of the data collection, the spring of 1997, the 2,544 girls and 2,627 boys were in grades 5 through 9, with modal ages of 11 through 15 years. Aggr. Behav. 29:239–268, 2003. © 2003 Wiley‐Liss, Inc. 相似文献
66.
We investigate a contractionless naive set theory, due to Grisin [11]. We prove that the theory is undecidable. 相似文献
67.
Koji Sakai 《The Japanese psychological research》2003,45(2):122-128
Abstract: A two-interval forced-choice of constant stimuli was used to measure the point of subjective equality (PSE) and discrimination threshold for standard contour curvature (1.91, 3.24 deg−1 ) held in short-term visual memory (STVM). At both standard curvatures, the PSE for remembered curvature was nearly constant for standard curvature from 2 s to 16 s retention intervals, while the discrimination threshold increased as a linear function of retention interval. These results show that the decay in STVM for contour curvature is due to the noisy representation of curvature, neither to fading of the represented curvature nor to converging to the constant curvature. Furthermore, the Weber fraction was nearly constant for both standard curvatures at any delay from 2 to 16 s. 相似文献
68.
于保荣 《医学与哲学(人文社会医学版)》2008,29(12)
提出制约新农合制度发展的瓶颈有:筹资方式及筹资成本问题、筹资水平、补偿内容的设计问题、过多照搬了城镇职工基本医疗保险的资金管理方式、管理能力与管理手段、位于卫生局内的合管办、无法实现“解决因病致贫、因病返贫”的政策目标。 相似文献
69.
Cohen SL 《Journal of the experimental analysis of behavior》1975,24(3):333-341
Responses on one key (the main key) of a two-key chamber produced food according to a second-order variable-interval schedule with fixed-interval schedule components. A response on a second key (the changeover key) alternated colors on the main key and provided a second independent second-order variable-interval schedule with fixed-interval components. The fixed-interval component on one variable-interval schedule was held constant at 8 sec, while the fixed interval on the other variable-interval schedule was varied from 0 to 32 sec. Under some conditions, a brief stimulus terminated each fixed interval and generated fixed-interval patterns; in other conditions, the brief stimulus was omitted. Relative response rate and relative time deviated substantially from scheduled relative reinforcement rate and, to a lesser extent, from obtained relative reinforcement rate under both brief-stimulus and no-stimulus conditions. Matching was observed with equal components on both schedules; with unequal components, increasingly greater proportions of time and responses than the matching relation would predict were spent on the variable-interval schedule containing the shorter component. Preference for the shorter fixed interval was typically more extreme under brief-stimulus than under no-stimulus schedules. The results limit the extension of the matching relation typically observed under simple concurrent variable-interval schedules to concurrent second-order variable-interval schedules. 相似文献
70.