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191.
192.
The inhalation of 7.5% CO2 has been shown to induce cognitive effects similar to anxiety. Sixteen healthy participants (14 male; mean age 25.6 years) inhaled either a mixture of 7.5% CO2 gas or air while playing a group combat computer game. Participants reported greater feelings of anxiety and fired fewer bullets when inhaling CO2 compared with air, indicating CO2-induced anxiety may improve efficiency without task-related decrements. Being able to induce controlled and measured anxiety in group situations by CO2 inhalation may be a useful technique when evaluating response to stressful situations, such as combat, in simulators or real-life scenarios.  相似文献   
193.
A formalism for optimized many body (OMB) potentials to describe the interatomic interactions in fcc metals is described. The OMB approach is based on the Tersoff potential, widely used to describe covalently bonded materials, and is closely related to the charge optimized many body (COMB) potential formalism for oxides. OMB extends to first nearest neighbors only, and employs a third-order Legendre polynomial to distinguish fcc and hcp structures, the strength of which can be adjusted to match the intrinsic stacking fault energy to arbitrary precision. The potential also predicts generalized stacking fault energy curves that are in very close agreement to the values determined from electronic-structure calculations. This potential is thus well-suited to investigating mechanical properties such as plastic deformation at the atomic scale.  相似文献   
194.
ABSTRACT

The Autobiographical Memory Test (AMT) has been central in psychopathological studies of memory dysfunctions, as reduced memory specificity or overgeneralised autobiographical memory has been recognised as a hallmark vulnerability for depression. In the AMT, participants are asked to generate specific memories in response to emotional cue words, and their responses are scored by human experts. Because the manual coding takes some time, particularly when analysing a large dataset, recent studies have proposed computerised scoring algorithms. These algorithms have been shown to reliably discriminate between specific and non-specific memories of English-speaking children and Dutch- and Japanese-speaking adults. The key limitation is that the algorithm is not developed for English-speaking adult memories, which may cover a wider range of vocabulary that the existing algorithm for English-speaking child memories cannot process correctly. In the present study, we trained a new support vector machine to score memories of English-speaking adults. In a performance test (predicting memory specificity against human expert coding), the adult-memory algorithm outperformed the child-memory variant. In another independent performance test, the adult-memory algorithm showed robust performances to score memories that were generated in response to a different set of cues. These results suggest that the adult-memory algorithm reliably scores memory specificity.  相似文献   
195.
The paper starts with a critics of the potential information which is related to the statistical entropy. In order to include the syntactic and semantic aspects of information, we propose a distinction between structural and functional information, instead. Structural information represents the structural determination of a system state, it measures the content of information, as given by the material structure. Functional information, on the other hand, represents the operational closure of the system, it could be e.g. an algorithm which activates and interprets the existing structural information.

From an evolutionary point of view, pragmatic information is generated by an interplay of structural and functional information. This leads to a new insight into the concept of pragmatic information, which is not an invariant of evolution, but must be steadily re‐generated.

The active role of information in a self‐organization process is demonstrated in a model of artificial agents. It is shown by means of computer simulations that the feedback of already existing information on the generation of new information performs analogies to the creation of a collective memory.  相似文献   
196.
Although the literature on reinforcement in behavioral psychology is extensive, few studies have examined the derived transformation of reinforcing functions in accordance with equivalence classes, and no published research has yet examined the derived transformation of consequential functions in accordance with nonequivalence relations. In the present study, which consisted of four experiments, the basic preparation was as follows. First, an arbitrary stimulus, B2, was established as a conditioned punisher, using direct stimulus pairing. Following nonarbitrary relational training, designed to establish SAME and OPPOSITE contextual cues, subjects were exposed to arbitrary relational training using these contextual cues to establish A1 as the same as B1 and C1, and as opposite to B2 and C2. Subsequently, C2 (based on its Same relation with B2) functioned as a punisher and C1 (based on its Opposite relation with B2) functioned as a reinforcer in a simultaneous discrimination task. Critically, the C1 stimulus acquired reinforcing functions, based on the derived relation of Opposite, although no such function had actually been established for any member of the network. Furthermore, these effects were observed across ABA reversals in the baseline contingencies.  相似文献   
197.
We assessed choices on a computerized test of self-control (CTSC) for a group of children with features of attention deficit hyperactivity disorder (ADHD) and a group of controls. Thirty boys participated in the study. Fifteen of the children had been rated by their parents as hyperactive and inattentive, and 15 were age- and gender-matched controls in the same classroom. The children were observed in the classroom for three consecutive mornings, and data were collected on their activity levels and attention. The CTSC consisted of two tasks. In the delay condition, children chose to receive three rewards after a delay of 60 s or one reward immediately. In the task-difficulty condition, the children chose to complete a difficult math problem and receive three rewards or complete an easier problem for one reward. The children with ADHD features made more impulsive choices than their peers during both conditions, and these choices correlated with measures of their activity and attention in the classroom.  相似文献   
198.
The author has surveyed a quarter of the accredited undergraduate computer science programs in the United States. More than half of these programs offer a “social and ethical implications of computing” course taught by a computer science faculty member, and there appears to be a trend toward teaching ethics classes within computer science departments. Although the decision to create an “in house” computer ethics course may sometimes be a pragmatic response to pressure from the accreditation agency, this paper argues that teaching ethics within a computer science department can provide students and faculty members with numerous benefits. The paper lists topics that can be covered in a computer ethics course and offers some practical suggestions for making the course successful. An earlier version of this paper was presented at the 2005 conference, Ethics and Social Responsibility in Engineering and Technology, Linking Workplace Ethics and Education, co-hosted by Gonzaga University and Loyola Marymount University, Los Angeles, California, 9–10 June 2005.  相似文献   
199.
Courses on ethics and technology have become compulsory for many students at the three Dutch technical universities during the past few years. During this time, teachers have faced a number of didactic problems, which are partly due to a growing number of students. In order to deal with these challenges, teachers in ethics at the three technical universities in the Netherlands — in Delft, Eindhoven and Twente — have developed a web-based computer program called Agora (see www.ethicsandtechnology.com). This program enables students to exercise their ethical understanding and skills extensively. The program makes it possible for students to participate actively in moral reflection and reasoning, and to develop the moral competencies that are needed in their later professional practice. The developers of the program have tried to avoid two traps. Firstly, they rejected, from the outset, a cookbook style of dealing with ethical problems that applied ethics is often taken to be and, secondly, they wanted to design a flexible program that respects the student’s as well as the teacher’s creativity, and that tries to engage students in moral reflection. Agora meets these requirements. The program offers possibilities that extend beyond the requirements that are usually accepted for case-exercises in applied ethics, and that have been realised in several other computer models for teaching ethics. In this article, we describe the main considerations in the development of Agora and the features of the resulting program.  相似文献   
200.
Two experiments compared performances on conditional discrimination tasks using single-participant designs with and without speed contingencies. Experiment 1 was a systematic replication of Spencer and Chase (1996). Experiment 2 presented equal numbers of training and testing trials. In each experiment, 2 female undergraduates participated. Each formed three five-member and three seven-member equivalence classes in Experiments 1 and 2, respectively. Response speed was an inverse function of nodal number and relational type in Experiment 1, but only of relational type (i.e., baseline, symmetry, transitivity, and equivalence) in Experiment 2, with and without the speed contingency. Accuracy tended to peak without the speed contingency in both experiments. Adding the speed contingency increased response speeds in both experiments, more so in Experiment 2 with a lower limited hold for I participant. The results of Experiment 2 cast doubt on previous reports of the nodality effect and on the notion of "relatedness" among class members, and they support a reinforcement-contingency, rather than a structural, account of equivalence class formation.  相似文献   
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