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161.
This paper attempts an interpretation of Everett's relative state formulation of quantum mechanics that avoids the commitment to new metaphysical entities like worlds or minds. Starting from Everett's quantum mechanical model of an observer, it is argued that an observer's belief to be in an eigenstate of the measurement (corresponding to the observation of a well-defined measurement outcome) is consistent with the fact that she objectively is in a superposition of such states. Subjective states corresponding to such beliefs are constructed. From an analysis of these subjective states and their dynamics it is argued that Everett's pure wave mechanics is subjectively consistent with von Neumann's classical formulation of quantum mechanics. It follows from the argument that the objective state of a system is in principle unobservable. Nevertheless, an adequate concept of empirical reality can be constructed. 相似文献
162.
163.
Double dissociations in visual and spatial short-term memory 总被引:11,自引:0,他引:11
A visual short-term memory task was more strongly disrupted by visual than spatial interference, and a spatial memory task was simultaneously more strongly disrupted by spatial than visual interference. This double dissociation supports a fractionation of visuospatial short-term memory into separate visual and spatial components. In 6 experiments, this interpretation could be defended against alternative explanations in terms of trade-offs in resource allocation between memory tasks and interference tasks, in terms of an involvement of short-term consolidation and long-term memory, in terms of differential phonological-loop and central-executive involvement, and in terms of similarity-based interference. 相似文献
164.
We describe a noncontact method for the ambulant measurement of basic sleep physiology parameters in humans, particularly
for field studies involving sleep research and sleep disturbances. This method traces the body movements, respiration, and
heart action of a person at rest or asleep on a bed, using four high-resolution force sensors installed under the bedposts.
The recoil movement of the body at each heartbeat, known as the cardioballistic effect, as well as the lifting and lowering
of the thorax, while breathing, causes very small shifts of the center of gravity of the bed and the subject. These shifts
are reflected in the altering force distributions across the four sensors. Cardiac and respiratory parameters and the subject’s
movement activity can be calculated from the sensor signals. Neither electrodes nor other kinds of transducers are in direct
contact with the subject, which is the main advantage of this technique over conventional methods. Laboratory experiments
were carried out to estimate validity and practicability. The method has been found to be adequate, especially for automated
and unattended sleep-data collection over long periods of time. 相似文献
165.
Classical automated theorem proving of today is based on ingenious search techniques to find a proof for a given theorem in very large search spaces—often in the range of several billion clauses. But in spite of many successful attempts to prove even open mathematical problems automatically, their use in everyday mathematical practice is still limited.The shift from search based methods to more abstract planning techniques however opened up a paradigm for mathematical reasoning on a computer and several systems of that kind now employ a mix of interactive, search based as well as proof planning techniques.The Ωmega system is at the core of several related and well-integrated research projects of the Ωmega research group, whose aim is to develop system support for a working mathematician as well as a software engineer when employing formal methods for quality assurance. In particular, Ωmega supports proof development at a human-oriented abstract level of proof granularity. It is a modular system with a central proof data structure and several supplementary subsystems including automated deduction and computer algebra systems. Ωmega has many characteristics in common with systems like NuPrL, CoQ, Hol, Pvs, and Isabelle. However, it differs from these systems with respect to its focus on proof planning and in that respect it is more similar to the proof planning systems Clam and λClam at Edinburgh. 相似文献
166.
Studies monitoring eye-movements in scenes containing entities have provided robust evidence for incremental reference resolution processes. This paper addresses the less studied question of whether depicted event scenes can affect processes of incremental thematic role-assignment. In Experiments 1 and 2, participants inspected agent-action-patient events while listening to German verb-second sentences with initial structural and role ambiguity. The experiments investigated the time course with which listeners could resolve this ambiguity by relating the verb to the depicted events. Such verb-mediated visual event information allowed early disambiguation on-line, as evidenced by anticipatory eye-movements to the appropriate agent/patient role filler. We replicated this finding while investigating the effects of intonation. Experiment 3 demonstrated that when the verb was sentence-final and thus did not establish early reference to the depicted events, linguistic cues alone enabled disambiguation before people encountered the verb. Our results reveal the on-line influence of depicted events on incremental thematic role-assignment and disambiguation of local structural and role ambiguity. In consequence, our findings require a notion of reference that includes actions and events in addition to entities (e.g. Semantics and Cognition, 1983), and argue for a theory of on-line sentence comprehension that exploits a rich inventory of semantic categories. 相似文献
167.
Filip Lievens Jan Corstjens Christoph N. Herde 《International Journal of Selection & Assessment》2023,31(2):240-251
Recently, shorter assessments have emerged as potential alternatives for more resourceful traditional selection approaches. Multiple, speeded assessments (MSAs) represent such an alternative. In MSAs, candidates participate in a large number of short (a maximum of 5 min), behavioral simulations in which they face a variety of job situations. Initial psychometric evidence on the validity of MSAs is promising. Yet, validity represents only one piece of evidence. It is not known whether MSAs disadvantage specific subgroups, which may inhibit diversity. There is also no information on candidates' experience of going through an MSA, which is pivotal for the attractiveness of the organization's selection process. Therefore, this study investigates an MSA in terms of subgroup differences (gender and nationality) and applicant perceptions. Master of Business Administration (MBA) students (N = 96) proceeded through 18 short role-plays sampling junior management situations. Score differences between men and women were negligible. Yet, there were large score differences between national citizens and foreigners. There was no evidence for predictive bias for nationality, though. Of the applicant reaction measures, interpersonal treatment perceptions contributed most to overall fairness perceptions. These findings add to the evidence in support of MSAs, while also stressing to remain vigilant for potential score differences among subgroups. 相似文献
168.
Karl Christoph Klauer 《Kognitionswissenschaft》1998,7(1):11-18
The present paper provides evidence for a differential involvement of spatial and visual mental resources in propositional and spatial reasoning. Two experiments consider the load on visuospatial working memory during reasoning. Subjects solve propositional and spatial reasoning tasks either alone or in combination with visual tracking. In the first experiment, subjects resource allocation strategy is manipulated. Independently of the allocation of mental resources to the reasoning tasks or the tracking task, tracking is found to interfere much more with spatial than with propositional reasoning. In the second experiment, propositional reasoning after a comprehension training is disrupted by a simultaneous secondary spatial task, but not by the visual tracking task. 相似文献
169.
Peter A. Singer Mark Siegler John D. Lantos Jean C. Emond Peter F. Whitington J. Richard Thistlethwaite Christoph E. Broelsch 《Theoretical medicine and bioethics》1990,11(2):87-94
Liver transplantation is the treatment of choice for many forms of liver disease. Unfortunately, the scarcity of cadaveric donor livers limits the availability of this technique. To improve the availability of liver transplantation, surgeons have developed the capability of removing a portion of liver from a live donor and transplanting it into a recipient. A few liver transplants using living donors have been performed worldwide. Our purpose was to analyze the ethics of liver transplants using living donors and to propose guidelines for the procedure before it was introduced in the United States. We used a process of “research ethics consultation” that involves a collaboration between clinical investigators and clinical ethicists. We concluded that it was ethically appropriate to perform liver transplantation using living donors in a small series of patients on a trial basis, and we published our ethical guidelines in a medical journal before the procedure was introduced. We recommend this prospective, public approach for the introduction of other innovative therapies in medicine and surgery. 相似文献
170.
Karl Christoph Klauer 《Psychometrika》1989,54(4):737-750
Ordinal network representations are graph-theoretic representations of proximity data. They seek to provide parsimonious representations of the ordinal (nonmetric) information in observed proximity data by means of the minimum-path-length distance of a connected and weighted graph. In contrast to traditional tree-based graph-theoretic approaches, ordinal network representation is not limited to but includes the representation by trees. Asymmetry in the proximity data and violations of zero-minimality are allowed for. The paper explores fundamental representation and uniqueness results and discusses a method of constructing ordinal network representations. A simple strategy for handling the problem of errors in the data is described and illustrated.This work was supported by grant Fe 75/20-2 of the Deutsche Forschungsgemeinschaft. The author is indebted to Hubert Feger for many inspiring discussions. 相似文献