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51.
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   
52.
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   
53.
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   
54.
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   
55.
Studies of the development of mental rotation have yielded conflicting results, apparently because different mental rotation tasks draw on different cognitive abilities. Children may compare two stimuli at different orientations without mental rotation if the stimuli contain orientation-free features. Two groups of children (78 6-year-olds and 92 8-year-olds) participated in an experiment investigating development of the ability to mentally rotate and the ability to recognize and use orientation-free features. Children compared two stimuli, one upright and one rotated, and responded as quickly as possible indicating whether the stimuli were the same or different. The stimuli were either two panda bears or two ice-cream cones with three scoops of ice-cream of different colors. The panda bears were either identical or mirror images. The cones were either identical, mirror images, or non-mirror images. Response times increased linearly as a function of the angle of orientation when stimuli were the same and when the stimuli were mirror images. But response times were much less dependent on angle of orientation for non-mirror image stimuli. Children as young as 6 years recognized orientation-free stimulus features and responded without mentally rotating when the task permitted this strategy.  相似文献   
56.
This article presents the results of a pilot study carried out on families of people with a diagnosis of schizophrenia (high‐frequency users of psychiatric services) using a standardized version of systemic family intervention based on the Milan Approach (‘Circular Interview’). We used expressed emotion (EE) to compare and assess two homogeneous samples of families, a treatment group (n = 10) and a control group (n = 8). We found that families participating in circular interviews showed a reduction in criticism, while 30% of their members with a diagnosis of schizophrenia relapsed. Families not receiving treatment showed no changes in EE levels, while 62.5% of their members with a diagnosis of schizophrenia relapsed. Although the difference in relapse rates is not statistically significant, these results justify further studies on the use of nondirective systemic intervention with families of people with a diagnosis of schizophrenia.  相似文献   
57.
The present study investigated the association of impulsivity, aggression and self-efficacy with protective factors against suicide. The study population consisted of 300 Italian university students (141 males, 159 females); mean age 24.2 (SD = 3.01). Participants were assessed by means of the Reasons for Living Inventory, the Aggression Questionnaire, the Barratt Impulsiveness Scale, and the General Self-Efficacy Scale. Correlations between reasons for living and aggression and impulsivity scores were weak. However, for those individuals with high self-efficacy, aggression and impulsivity were associated with stronger reasons for living. These results support the possibility that increasing general self-efficacy could be a useful target for interventions directed toward suicide prevention in individuals with problems in emotional control.  相似文献   
58.
Interaction design of mobile systems is a complex activity because it requires considering new usability and user experience aspects in order to exploit the peculiar characteristics of mobile devices, such as their pervasive and ubiquitous nature. This paper discusses issues about designing, developing and evaluating mobile systems. Italy has a rich cultural heritage, and the focus in this study is on the design of systems that enable interactive exploration of historical sites, not only for enhancing the user experience but also for learning purposes. The experience of the researchers at the Interaction, Visualisation and Usability lab, University of Bari, Italy, in designing a mobile learning system, called Explore!, which supports young students learning ancient history during a visit to archaeological parks, is reported. The evaluation of Explore! through systematic field studies shows that the adopted approach is able to transform the visit to archaeological parks into a more complete and culturally rich experience.  相似文献   
59.
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   
60.
We describe a letter-by-letter patient who produced misreading errors in both letters in isolation and in words. All errors were visual in nature. We hypothesized an access deficit to the abstract visual representation of letters that prevents letter identification. This deficit could account for the patient's letter-by-letter behavior, since each letter constituted a potential identification problem. An access deficit, moreover, could also explain the patient's letter visual errors. In access processing, in fact, the letters sharing common structural features in their abstract representations were the ones more frequently mismatched.  相似文献   
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