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41.
42.
Engineers must deal with risks and uncertainties as a part of their professional work and, in particular, uncertainties are inherent to engineering models. Models play a central role in engineering. Models often represent an abstract and idealized version of the mathematical properties of a target. Using models, engineers can investigate and acquire understanding of how an object or phenomenon will perform under specified conditions. This paper defines the different stages of the modeling process in engineering, classifies the various sources of uncertainty that arise in each stage, and discusses the categories into which these uncertainties fall. The paper then considers the way uncertainty and modeling are approached in science and the criteria for evaluating scientific hypotheses, in order to highlight the very different criteria appropriate for the development of models and the treatment of the inherent uncertainties in engineering. Finally, the paper puts forward nine guidelines for the treatment of uncertainty in engineering modeling.  相似文献   
43.
A proof-theoretic analysis and new arithmetical semantics are proposed for some paraconsistent C-systems, which are a relevant sub-class of Logics of Formal Inconsistency (LFIs) introduced by W.A. Carnielli et al. (2002, 2005) [8] and [9]. The sequent versions BC, CI, CIL of the systems bC, Ci, Cil presented in Carnielli et al. (2002, 2005) [8] and [9] are introduced and examined. BC, CI, CIL admit the cut-elimination property and, in general, a weakened sub-formula property. Moreover, a formal notion of constructive paraconsistent system is given, and the constructivity of CI is proven. Further possible developments of proof theory and provability logic of CI-based arithmetical systems are sketched, and a possible weakened Hilbert?s program is discussed. As to the semantical aspects, arithmetical semantics interprets C-system formulas into Provability Logic sentences of classical Arithmetic PA (Artemov and Beklemishev (2004) [2], Japaridze and de Jongh (1998) [19], Gentilini (1999) [15], Smorynski (1991) [22]): thus, it links the notion of truth to the notion of provability inside a classical environment. It makes true infinitely many contradictions B∧¬B and falsifies many arbitrarily complex instances of non-contradiction principle ¬(A∧¬A). Moreover, arithmetical models falsify both classical logic LK and intuitionistic logic LJ, so that a kind of metalogical completeness property of LFI-paraconsistent logic w.r.t. arithmetical semantics is proven. As a work in progress, the possibility to interpret CI-based paraconsistent Arithmetic PACI into Provability Logic of classical Arithmetic PA is discussed, showing the role that PACIarithmetical models could have in establishing new meta-mathematical properties, e.g. in breaking classical equivalences between consistency statements and reflection principles.  相似文献   
44.
In four experiments, a computerized Corsi-like paradigm was used to assess which of the many reference frames are used in visuospatial short-term memory. By varying the relative orientation (slanted +/-45° or in an upright position) of the head and the displays, we modulate the utility of the allocentric, egocentric (eye- and head-centred), and template-centred reference frames. The results of all experiments showed the crucial importance of the gravitational allocentric reference frames while using visuospatial short-term memory to retain a spatial sequence of elements. The results also provide some support for a mental rotation process involved in recognition following angular displacement of a multi-item display.  相似文献   
45.
在其1943年一篇题为“尼采的话‘上帝死了”’的文章结尾处,海德格尔说道:宣称上帝之死的“疯子正是大声叫喊着‘上帝’而寻找上帝的人。在这里,可能真的是一位思想者发自心底的叫喊?而我们思想的耳朵呢?……除非我们开始思想,否则就听不到这种叫喊。只有当我们已经体会到,干百年来被人们颂扬不绝的理性乃是思想最顽固的敌人,思想才能启程”(海德格尔,1975-,v:267)。  相似文献   
46.
Impulsivity and reward sensitivity are often treated as interchangeable constructs. This conflation may be traced back to Gray’s interpretation of impulsivity as the trait level manifestation of the Behavioral Activation System (BAS), that mediates sensitivity to rewards. In this study (N = 696) we evaluated discriminant hypotheses regarding the relationships between BAS-mediated reward sensitivity, impulsivity and Eysenck’s PEN superfactors. We hypothesized that reward sensitivity would be mainly linked with Extraversion, and that impulsivity would be primarily connected with Psychoticism. Hypotheses were tested using structural equation modelling and equality constraints tests. Results mostly supported our expectations: reward sensitivity was more strongly related to Extraversion than to the other PEN superfactors, while impulsivity was more strongly related to Psychoticism and Neuroticism. Implications for BAS and impulsivity research are discussed.  相似文献   
47.
Based on structural differences between spoken and written language, the purpose of this paper was to investigate whether spoken and written communication imply a different representation in reporting an experienced dream. In fact, the clausal-dynamic quality of the former and nominal-synoptic quality of the latter, with the consequent differences in length, cohesion and density, could enhance/reduce the perceptual character and narrative structure of report features often considered in order to assess sleep mentation. In particular, we wondered whether, after eliminating all the elements responsible for the more conspicuous quantitative differences across the two forms (false starts, repetitions, digressions, redundancies), we would obtain two equivalent ways of reporting dreams. Three hundred and two (101 males and 201 females) subjects, raging in age from 18 to 40 years, participated as volunteers in the study and were asked to complete a dream diary daily for 14 days, by tape-recording their own dreams and putting them down in writing. The reports were analyzed by a psycholinguistic system. Results indicated that the report modality is able to affect the dream experience representation, conditioning the figurative (re)translation carried out by the tester: written forms show a loss of hallucinatory information and a non-complete correspondence also of the bizarreness features with respect to the spoken texts. Partialling out for length eliminated any difference between spoken and written dream reports on bizarreness; on the other hand, controlling the sequence effect of the report did not introduce changes. Methodological and theoretical implications were discussed.  相似文献   
48.
The aim of the study was to assess the effects of visual aesthetic perception on event-related potentials (ERPs). Eight subjects assigned an aesthetic judgment (beautiful, neutral, or ugly) and a 10-step beauty estimation to the target stimuli, consisting of famous artistic pictures and geometric shapes. In a further task, the subjects performed a motor response to the previously judged pictures and geometric shapes. ERPs were recorded through 54 scalp electrodes during both tasks. The P3b amplitude was increased during the categorization of the geometric shapes compared to the artistic figures and during the vision of the beautiful targets preceding the motor response. The categorization of the aesthetic qualities of geometrical shapes seems to induce a higher level of attention, while a higher arousal variation was elicited by the recognition of beauty, in any form that was presented.  相似文献   
49.
Aesthetic value of paintings affects pain thresholds   总被引:1,自引:0,他引:1  
Pain is modulated by cognitive factors, including attention and emotions. In this study we evaluated the distractive effect of aesthetic appreciation on subjectively rated pain (visual analogue scale;VAS) and multi-channel evoked potentials induced by CO2 laser stimulation of the left hand in twelve healthy volunteers. Subjects were stimulated by laser in the absence of other external stimulation (baseline condition) and while looking at different paintings they had previously rated as beautiful, neutral or ugly. The view of paintings previously appreciated as beautiful produced lower pain scores and a clear inhibition of the P2 wave amplitude, localized in the anterior cingulate cortex; the inhibition of P2 wave amplitude was lesser or not significant during the presentation of the ugly or neutral paintings, respectively. Dipole source localization analysis of the LEP peaks showed significant changes during different conditions, with a shift from the posterior to the anterior right cingulated cortex while looking at paintings previously rated as beautiful.Our results provide evidence that pain may be modulated at cortical level by the aesthetic content of the distracting stimuli.  相似文献   
50.
In this paper, we present a Capabilities-based Approach to the acceptability and the tolerability of risks posed by natural and man-made hazards. We argue that judgments about the acceptability and/or tolerability of such risks should be based on an evaluation of the likely societal impact of potential hazards, defined in terms of the expected changes in the capabilities of individuals. Capabilities refer to the functionings, or valuable doings and beings, individuals are able to achieve given available personal, material, and social resources. The likely impact of a hazard on individuals' capabilities should, we argue, be compared against two separate thresholds. The first threshold specifies the minimum level of capabilities attainment that is acceptable in principle for individuals to have in the aftermath of a hazard over any period of time. This threshold captures the level that individuals' capabilities ideally should not fall below. A risk is acceptable if the probability that the attained capabilities will be less than the acceptable level is sufficiently small. In practice, it can be tolerable for some individuals to temporarily fall below the acceptable threshold, provided this situation of lower capabilities attainment is temporary, reversible, and the probability that capabilities will fall below a tolerability threshold is sufficiently small. This second, tolerable threshold delimits an absolute minimum level of capabilities attainment below which no individual in a society should ever fall, regardless of whether that level of capabilities attainment is temporary or reversible. In this paper, we describe and justify this Capabilities-based Approach to the acceptability and tolerability of risks. We argue that the proposed theoretical framework avoids the limitations in current approaches to acceptable risk. The proposed approach focuses the attention of risk analysts directly on what should be our primary concern when judging the acceptability and the tolerability of risks, namely, how risks impact the well-being of individuals in a society. Also, our Capabilities-based Approach offers a transparent, easily communicable way for determining the acceptability and the tolerability of risks.  相似文献   
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