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41.
We trace self-reference phenomena to the possibility of namingfunctions by names that belong to the domain over which thefunctions are defined. A naming system is a structure of theform (D, type( ),{ }), where D is a non-empty set; for everya D, which is a name of a k-ary function, {a}: Dk D is thefunction named by a, and type(a) is the type of a, which tellsus if a is a name and, if it is, the arity of the named function.Under quite general conditions we get a fixed point theorem,whose special cases include the fixed point theorem underlyingGödel's proof, Kleene's recursion theorem and many othertheorems of this nature, including the solution to simultaneousfixed point equations. Partial functions are accommodated byincluding "undefined" values; we investigate different systemsarising out of different ways of dealing with them. Many-sortednaming systems are suggested as a natural approach to generalcomputatability with many data types over arbitrary structures.The first part of the paper is a historical reconstruction ofthe way Gödel probably derived his proof from Cantor'sdiagonalization, through the semantic version of Richard. Theincompleteness proof–including the fixed point construction–resultfrom a natural line of thought, thereby dispelling the appearanceof a "magic trick". The analysis goes on to show how Kleene'srecursion theorem is obtained along the same lines.  相似文献   
42.
    
This paper critically examines a formal argument against deducing ought-judgments from is-judgments, an argument suggested by a literal reading of a famous passage in Hume'sTreatise of Human Nature. According to this argument, judgments of the two kinds have different logical structures (i.e., their subjects are differently related to their predicates) and this difference disallows cross-categorical deductive inferences. I draw on Fregean accounts of the is- copula and on syntactical interpretations of ought-judgments that have become standard in deontic logic to argue that twentieth century work in philosophical grammar and logic casts doubt on all three of the argument's premises.  相似文献   
43.
服务质量差异模型及应用   总被引:14,自引:0,他引:14  
服务是市场营销的重要因素。服务质量差异模型认为现实的服务、感受到的服务和期望的服务之间存在差异。消费者评价服务质量,有两种标准,一种是期望标准,一种是最低可接受标准,二者之差形成可接受区间。以该模型为指导的Servqual量表在服务质量研究领域得到了广泛的应用。  相似文献   
44.
45.
The value‐action gap poses a considerable challenge to normative environmental ethics. Because of the wide array of empirical research results that have become available in the fields of environmental psychology, education, and anthropology, ethicists are at present able to take into account insights on what effectively motivates proenvironmental behavior. The emotional aspect apparently forms a key element within a transformational process that leads to an internalization of nature within one's identity structure. We compare these findings with studies on environmental activists, which appear to a significantly lesser degree hampered by the value‐action gap, thereby attempting to understand what provides them with the drive to act more consistently on their moral attitudes. Hermeneutics is found to play a crucial role in the processes that lead to lasting and consistent motivation toward proenvironmental behavior. An empirically informed hermeneutical approach could therefore provide a promising impetus for contemporary environmental ethics.  相似文献   
46.
Irradiation of polymers has become an important technique in producing special materials for electronic applications. In this study, the effects of electron and gamma irradiation on ultra-high-molecular-weight polyethylene (UHMWPE) samples have been studied using UV–Vis absorption spectroscopy. The UHMWPE samples were irradiated with electron and gamma rays with doses ranging from 25 kGy up to 500 kGy. An increase in the optical absorption and a shifting from the UV–Vis towards longer wavelengths were observed. Concomitantly, a pronounced decrease in the optical band gap was recorded as a function of dose level. The optical band gap E g varied from 2.86 eV for a pristine sample down to ~1.98 eV and ~2 eV for samples irradiated with gamma rays and electrons at the highest doses, respectively. A correlation between E g and the number of carbon atoms N in a formed cluster is discussed in terms of a modified Tauc equation.  相似文献   
47.
ABSTRACT

Psychological treatment and assessment necessarily rely on patients’ recall. Yet several empirical studies have documented a gap between memory and real-life experience (i.e., memory–experience gap; MeG). We investigated and compared the MeG of sadness, social anxiety, happiness, and physical activity for participants diagnosed with a major depressive disorder (MDD), a social phobia (SP), and participants without such diagnoses (CG). The study included 118 participants diagnosed with a MDD, 47 with a SP, and 119 CG. Using event-sampling methods (ESM), participants were asked via smartphone to report their experiences throughout a week and then to recall those again retrospectively at the end of the study week. Results indicate significant differences in the MeG with respect to the experience that was salient to them (e.g., MDD group – sadness; SP group – social anxiety; CG group – happiness). Furthermore, all groups showed a MeG for physical activity and, the results indicate significant group differences in the magnitude of the MeGs.

This study demonstrated the presence of a MeG in individuals in a MDD, SP, and CG group and in positive and negative affective experiences. Differential patterns across the samples contribute to a better understanding of this gap and its implications.  相似文献   
48.
Objective

Two studies were conducted with the aim of closing the intention–behaviour gap for sunscreen use and sun protection behaviours by examining the influence of self-regulatory capacity on the prediction of sunscreen use (Study 1) and self-regulatory capacity and habit on sun protection behaviours (Study 2).

Design

Studies were conducted online. Participants completed questionnaires and cognitive measures and then reported behaviour one week later.

Main Outcome Measures

Questionnaires measuring intention and cognitive tasks measuring self-regulatory capacity were administered to 209 university students. One week later, participants reported behaviour. In Study 2, questionnaires measuring intentions, and habit and cognitive tasks measuring self-regulatory capacity were administered to 178 university students who reported behaviour one week later.

Results

Intention accounted for 7.1% of variance in sunscreen use, no measures of self-regulation accounted for variance in behaviour or moderated the intention–behaviour gap (Study 1). Intention, self-regulatory capacity and habit accounted for 56.1% of variance in sun protection behaviours (Study 2). Intention, self-regulatory ability and habit predicted behaviour, while habit moderated the intention–behaviour gap.

Conclusion

Interventions aimed at increasing sun protection behaviours should take into account level of intention, self-regulatory capacity and habit. Individuals may benefit from habit formation strategies and self-regulation training.  相似文献   
49.
The combination of low physical activity rates and increased cardiovascular deaths indicate the overwhelming need for behaviour change interventions that can effectively promote physical activity among sedentary women. This 11-week randomised controlled trial examined the effects of an implementation intentions intervention on sedentary women's walking behaviour. Seventy-five women (M age = 48.17) were randomly assigned to either a control group where they were required to self-monitor their daily pedometer-determined step count or to an experimental group where they were asked to form specific walking plans (i.e. implementation intentions) every 6 weeks and to self-monitor their daily pedometer-determined step count. Measures of exercise intentions, perceived behavioural control, scheduling and barrier self-efficacy were administered at baseline, week 6 and week 11. Analyses indicated higher step counts over the first 6 weeks for women in the experimental condition (p < 0.02). Furthermore, higher self-efficacy to schedule (p < 0.01) and overcome walking barriers (p < 0.03), as well as higher perceptions of behavioural control (p < 0.02) were found at week 11 for women in the experimental versus control condition. However, none of the control beliefs were found to mediate the effects of the intervention on the women's walking behaviour. Furthermore, the intervention did not have any effect on the strength of the goal intention–behaviour relationship. The findings suggest implementation intentions are an effective strategy for initiating leisure-time walking within sedentary women.  相似文献   
50.
Despite widespread recognition of a research–practice gap in multiple service sectors, less is known about how pre‐existing communication channels facilitate the flow of information between researchers and practitioners. In the current study, we applied an existing typology of brokerage developed by Gould and Fernandez (Sociol Methodol 19:89–126, 1989 ) to examine what types of brokerage facilitate information spread between researchers and educational practitioners. Specifically, we conducted semi‐structured interviews with 19 school administrators and staff in two public school districts regarding their experiences searching for information about instructional, health, and social skills programs. Using deductive content analysis, we found evidence of all five types of brokerage identified by Gould and Fernandez ( 1989 ). However, only three types of brokerage—gatekeepers, representatives, and liaisons—were involved in the flow of information between school administrators and researchers. Moreover, information transfer often occurred in longer chains that involved multiple, distinct types of brokerage. We conclude with the broad implications of our findings for narrowing the research–practice gap by improving researchers’ dissemination efforts and practitioners’ search for information.  相似文献   
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