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101.
Spoken natural language interfaces are characterized by a high degree of opacity. This characteristic leads many new users to converse with the machine on the basis of an inaccurate image of the system, which results in numerous dysfunctions and failures in the human-machine spoken dialogue. The application of the principle of transparency aims to correct this problem by enabling the system to make it “visible” (it can, so to speak, be seen “from the inside”). This report presents a study that compares two versions of the same spoken dialogue system that differ only by some of their dialogue strategies. In particular, one version of this system starts the dialogue with a recall of the main system's function followed by an open-ended prompt, while the other version only produces an open-ended prompt (What can I do for you?). Moreover, one version of this system makes explicit some possible actions in specific dialogue contexts, while the other version leaves these possible actions implicit. These strategies were compared by having a group of 28 users test them in real conditions of use. The results highlight that transparency strategies can help users in formulating simple and acceptable requests, satisfying their goals more easily while provoking less recognition and comprehension errors.  相似文献   
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103.
This paper deals with the performance of delay-sensitive applications running over a network that offers multiple classes of service, where the adaption of application rates in response to network feedback is the primary mechanism available for controlling quality of service. We first evaluate the gain in utilisation allowed by the introduction of several classes of service. To this end we compare the pairs of achievable rates, or schedulable regions, for two types of applications with two distinct delay requirements that make use of a single resource, with either no differentiation, simple priority-based differentiation, or earliest-deadline-first (EDF) scheduling-based differentiation. The main observations are that the gain achieved by differentiation is essentially affected by traffic burstiness, and that the two differentiation schemes yield very similar performance.

We then consider what feedback information should be sent to traffic sources from different classes, casting the problem in the framework of optimisation-based congestion control. We establish a connection between the sample-path shadow price rationale for feedback synthesis and the rare perturbation analysis technique for gradient estimation in discrete event systems theory. Based on this connection, we propose several marking schemes, for simple priority-based differentiation with a measure of cost based on loss or delay, and also for EDF-based differentiation with loss-based cost. The interaction of these marking algorithms with simple congestion control algorithms is studied via simulations.  相似文献   

104.
The frequency stability of an atomic fountain clock can be limited by the phase noise of the interrogation oscillator via the "Dick effect." In this paper we demonstrate the rejection of the phase fluctuations of the interrogation oscillator by the synchronization of atomic fountains. A reduction by a factor of 16 in the Allan standard deviation of the relative frequency difference between two fountains has been obtained.  相似文献   
105.
106.
Differences among agents may be constructive in so far as they can bring solution enhancements or conflicts, the second case leading to solution modifications. What is dealt with in this paper is a cooperation involving different rational agents resulting in more than a mere addition of the agents' individual skills, thanks to a process of approval and refutation of the current solution. Lakatos' work is taken as a basis and adapted to a set of cooperating agents, so as to define the concept of supfA-cooperation and the corresponding interaction model. Three case studies are given, involving SuprA-cooperating human or artificial agents.  相似文献   
107.
Adjuvant immunotherapy with interferons and/or interleukin 2 (IL-2) is widely used for advanced kidney cancer. However, the results are not satisfactory so far. The purpose of this study is to evaluate the inducible activity of lymphokine-activated killer (LAK) cells against autologous human renal cell carcinoma. The effect of interleukin 7 (IL-7) on IL-2-induced LAK activity was assessed by the autologous assay system which we have established. Peripheral blood lymphocytes from patients with renal cell carcinoma were stimulated with IL-2 and/or IL-7, and tested for antitumor activity against autologous renal cell carcinoma. In all 10 cases tested, IL-7 alone induced LAK activity. Moreover, IL-2-induced LAK activity was augmented by the concomitant addition of IL-7. Flow cytometry revealed an increase in IL-2-receptor-positive lymphocytes following incubation with IL-7. These results suggest that combination therapy using IL-2 and IL-7 may be a useful treatment for patients with advanced renal cell carcinoma.  相似文献   
108.
109.
The causes of learning disorders are numerous and, although some learning difficulties can be remedied by special educative measures only, many such problems, especially when they are more severe represent a disorder of the total personality. In such a case a diagnosis must be established by a team of different specialists. After a careful evaluation a treatment programme is planned and a choice is made among various specific therapies. Very often the treatment of learning disorders must take into account more or less important emotional factors. A combined approach of psychotherapy and remedial teaching is sometimes essential to attain some success in helping a child. Such a combination of treatments requires close cooperation between psychotherapist and special teacher. Their respective roles have to be frequently clarified and both gain in understanding of the child needs through mutual communication. Following the evolution of a child from two points of view demonstrates more and more clearly how the intellectual processes necessary for learning are subject to inhibiting patterns that are observed in neurotic defense mechanisms against emotional conflicts. In some instances this practical knowledge would be necessary to understand why a child does not profit from remedial measures and to determine how new techniques are to be used to help him. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
Electromechanical properties of (1-x)Pb (Mg1/3Nb2/3)O3-xPbTiO3 (PMN-PT) single crystals with x = 0.35 were investigated as a function of different external disturbances. The polarization dependence on the electromechanical properties was first studied in order to determine the best polarization path. The correlation with X-ray measured phase ratio is presented and shows that the maximum of electromechanical properties may be correlated with a minimum rhombohedral/tetragonal phase ratio. Temperature, stress, electric field, and time (aging) stability was studied in order to determine performance-limiting factors of these materials. The rhombohedral/tetragonal phase transition is observed on temperature (80 degrees C), inducing a decrease of the electromechanical coupling factor (from 85% to 50%); but the whole properties are recovered while returning to room temperature. Stress measurement shows a large depoling of sample for stresses above 30 MPa. The PMN-PT single crystals were found to be surprisingly stable during aging, except for mechanical and dielectric losses. The same tendency was found on alternating current (AC) electric field dependence.  相似文献   
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