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111.
A case situation arising in a normal interaction among people is the baseline for discussing properties of the theory of viewpoints. In particular we consider how to ensure agreement on the meaning of certain utterances by agents who have different perspectives on the situation, while maintaning other knowledge as private. We argue that communication should be modeled as adding facts to the common knowledge of agents. We introduce the principle of 'referent sharing' in communications and argue that common knowledge resulting from communication should only use constants whose referent is manifest to the parties involved.  相似文献   
112.
Although enthusiasm for measuring health-related quality of life (HRQL) in clinical trials exists, information is limited on the meaning of scores. We examined the relation between scores from the 34-item Medical Outcomes Study HIV Health Survey (MOS-HIV) and the more detailed HIV Overview of Problems-Evaluation System (HOPES) using the responses of 318 HIV-infected outpatients being treated in Los Angeles and Baltimore. With the HOPES problem statements as independent variables, statistically significant predictors of the variation in MOS-HIV scores for the Physical Function, Mental Health, and Energy/Fatigue scales were identified using stepwise regression. Approximately 60% to 70% of the variation in each of the scores was explained by five to seven different HOPES problem statements, with a single item explaining 47% to 59% of the variation. We created illustrative profiles for each of the three MOS-HIV scales using the HOPES items identified in the regressions. Independent of the scale, persons scoring in the top MOS-HIV quartile tended to report few if any problems, whereas a decline in score to the next quartile was characterized by functional difficulties (e.g., "HIV interferes with work"). The onset of specific problems might trigger further evaluation and potential intervention from health care providers to help maintain patient functioning.  相似文献   
113.
Ferromagnetic and perovskite-like thin films (<1m) of La1–xCaxMnO3+ have been routinely prepared by heat treatment of an amorphous La–Ca–Mn precursor. The precursor was electrodeposited cathodically in the absence of oxygen and water onto polished silver substrates from a nonaqueous solution of the components' nitrates. Analysis by X-ray diffraction and SQUID magnetometry shows these materials exhibit the appropriate structural and magnetic phases indicative of colossal magnetoresistance.  相似文献   
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4. Conclusions Diastolic LV function and myocardial HEP metabolism are impaired only when LVH is caused by permanent pressure or volume overload, and not by a temporary increase in cardiac workload during part of the day as in elite athletes. Therefore, training-induced and pressure/volume-overload-induced LVH seem to represent different phenotypes of LVH, possibly related to genetic reprogramming which only occurs during permanent cardiac overload [17]. Moreover, there is an association between impaired LV diastolic function and altered myocardial HEP metabolism in patients with hypertension and in patients with aortic valve disease. Finally we did not find a correlation between myocardial HEP metabolism and LV mass in any of the groups studied. The latter indicates that LVH should be regarded as an epiphenomenon to cardiac overload, and not as a primary factor causing abnormal HEP metabolism.  相似文献   
116.
The Millimetre and Infrared Testa Grigia Observatory 2.6-m Cassegrain telescope has been designed to allow high-sensitivity observations in the millimeter spectral range. For this purpose, in order to reduce unwanted contributions from local foregrounds, we adopted a sky-chopping technique, by wobbling the telescope subreflector. We describe the design and performance of the wobbling system, which can endure external forced two and three fields square-wave modulation and includes features such as high frequency, high amplitude, high duty cycle, low microphonics, and high stability.  相似文献   
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We present empirical results of an auction-based algorithm for dynamic allocation of tasks to robots. The results have been obtained both in simulation and using real robots. A distinctive feature of our algorithm is its robustness to uncertainties and to robot malfunctions that happen during task execution, when unexpected obstacles, loss of communication, and other delays may prevent a robot from completing its allocated tasks. Therefore tasks not yet achieved are resubmitted for bids every time a task has been completed. This provides an opportunity to improve the allocation of the remaining tasks, enabling the robots to recover from failures and reducing the overall time for task completion.  相似文献   
120.
Missing data are omnipresent in forestry research, and this poses problems in the analysis of primary data. Many statistical problems have been viewed as missing data problems. To cope with incomplete data, several methods are currently being used. They are all based on assumptions some of which might not be valid in a particular case. The choice mostly depends on the objective of the study. Considerable mensuration research is motivated by the need for yield projections that can support forest management decisions. This paper is focused on a new approach for filling gaps in diameter measurements on standing tree boles. Dealing with this problem, an attempt was made to examine the applicability of artificial neural network models for missing data estimation and to use the estimated values in the subsequent analysis. The procedure that should be followed in the development of such models is outlined. The results show good performance of the examined ANN models compared to regression treatments for missing data and ANN models demonstrate their adequacy and potential for filling gaps in diameter measurements on standing tree boles. The ANN models applied in this study are sufficiently general and have great potential to be applicable for estimating the missing values of many variables in environmental applications.  相似文献   
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