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41.
This paper reports the objectives, design approach and first results of a research project that aims to develop an intelligent computer-based learning environment for industrial applications. Jonas , an expert system, is part of a modelling/simulation environment which enables shopfloor workers to test and to put new philosophies of work into practice in the context of manufacture. Our approach is focused on three main ideas: the Intelligence Augmentation paradigm, user-centred system design and the constructionist theory of learning. The architecture of the modelling environment and the main features of Jonas are presented as an illustration of the design ideas discussed in the paper.  相似文献   
42.
Traditionally, recommender systems for the web deal with applications that have two dimensions, users and items. Based on access data that relate these dimensions, a recommendation model can be built and used to identify a set of N items that will be of interest to a certain user. In this paper we propose a multidimensional approach, called DaVI (Dimensions as Virtual Items), that consists in inserting contextual and background information as new user–item pairs. The main advantage of this approach is that it can be applied in combination with several existing two-dimensional recommendation algorithms. To evaluate its effectiveness, we used the DaVI approach with two different top-N recommender algorithms, Item-based Collaborative Filtering and Association Rules based, and ran an extensive set of experiments in three different real world data sets. In addition, we have also compared our approach to the previously introduced combined reduction and weight post-filtering approaches. The empirical results strongly indicate that our approach enables the application of existing two-dimensional recommendation algorithms in multidimensional data, exploiting the useful information of these data to improve the predictive ability of top-N recommender systems.  相似文献   
43.
Beliefs about emotion utility can influence context-sensitive emotion goals (i.e., desired emotional responses). Although key for emotion regulation, emotion goals have been overlooked in children and adolescents. In 2018–2019 results of Studies 1 and 2 showed that children (N = 192, Mage = 8.65, 47% girls, 96% White) were less motivated by and found anger less useful in confrontation than adolescents (N = 192, Mage = 12.96, 50% girls, 93% White) and adults (N = 195, Mage = 29.82, 51% women, 96% White). The link between emotion goals and beliefs about emotion utility was weaker in children. In 2021, Study 3 (N = 60, 8-year-olds, 47% girls, 90% White) ruled out expectations as a possible explanation for the previous findings. Context-sensitive utility of emotions may be acquired during development.  相似文献   
44.
Two fundamental processes usually arise in the production planning of many industries. The first one consists of deciding how many final products of each type have to be produced in each period of a planning horizon, the well-known lot sizing problem. The other process consists of cutting raw materials in stock in order to produce smaller parts used in the assembly of final products, the well-studied cutting stock problem. In this paper the decision variables of these two problems are dependent of each other in order to obtain a global optimum solution. Setups that are typically present in lot sizing problems are relaxed together with integer frequencies of cutting patterns in the cutting problem. Therefore, a large scale linear optimizations problem arises, which is exactly solved by a column generated technique. It is worth noting that this new combined problem still takes the trade-off between storage costs (for final products and the parts) and trim losses (in the cutting process). We present some sets of computational tests, analyzed over three different scenarios. These results show that, by combining the problems and using an exact method, it is possible to obtain significant gains when compared to the usual industrial practice, which solve them in sequence.  相似文献   
45.
The aim of this study was to determine the effect of two arm swing techniques, the simultaneous arm swing and the early arm swing, on vertical countermovement jump performance and on the contribution of the arms to vertical movement at the centre of mass (CM) during the propulsion phase. Participants were 28 athletes practicing sports in which the vertical jump constitutes a basic ability. Ground reaction forces were recorded by a force platform and the sagittal plane motion was recorded by a video camera. Although at take-off the vertical velocity (2.7 ± 0.2 m/s for simultaneous technique vs. 2.8 ± 0.2 m/s for early technique; p = 0.040) and position (1.18 ± 0.06 m for simultaneous vs. 1.17 ± 0.05 m for early; p = 0.033) of the CM were significantly different, no difference was observed in jump height (1.56 ± 0.01 m in both techniques). The arm action differed during the initial and final propulsion phases in both styles but the accumulated vertical contribution was similar. The practical implication in sports is that the use of the arm-swing technique to reach the maximum jump height should be determined by tactical demands instead of the technical execution of the arms.  相似文献   
46.
Based on a spatial extension of an R&D investment model, this paper measures the macroeconomic impact of the French R&D policy mix on business R&D using regional data. Our measure takes into account not only the direct effect of policies but also indirect effects generated by the existence of spatial interaction between regions. Using a unique database containing information on the levels of various R&D policy instruments received by firms in French NUTS3 regions over the period 2001–2011, our estimates of a spatial Durbin model with structural breaks and fixed effects reveal the existence of a negative spatial dependence among R&D investments in regions. In this context, while a-spatial estimates would conclude that all instruments have a crowding-in effect, we show that national subsidies are the only instrument that is able to generate significant crowding-in effects. On the contrary, it seems that the design, size and spatial allocation of funds from the other instruments (tax credits, local subsidies, European subsidies) lead them to act (in the French context) as beggar-thy-neighbor policies.  相似文献   
47.
The most common way of designing databases is by means of a conceptual model, such as E/R, without taking into account other views of the system. New object-oriented design languages, such as UML (Unified Modelling Language), allow the whole system, including the database schema, to be modelled in a uniform way. Moreover, as UML is an extendable language, it allows for any necessary introduction of new stereotypes for specific applications. Proposals exist to extend UML with stereotypes for database design but, unfortunately, they are focused on relational databases. However, new applications require complex objects to be represented in complex relationships, object-relational databases being more appropriate for these requirements. The framework of this paper is an Object-Relational Database Design Methodology, which defines new UML stereotypes for Object-Relational Database Design and proposes some guidelines to translate a UML conceptual schema into an object-relational schema. The guidelines are based on the SQL: 1999 object-relational model and on Oracle8i as a product example.Received: 22 January 2002, Revised: 10 June 2002, This paper is a revised and extended version of Extending UML for Object-Relational Database Design, presented in the UML2001 conference [17].  相似文献   
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49.
A particular twenty-first-century understanding of the Aztec concept nepantla, one which has recently taken hold in critical education thanks to the writings of Gloria Anzaldúa, does not accurately reflect traditional Aztec history and philosophy. This essay reveals why this is the case, demonstrating in detail the meaning of nepantla within the broader Aztec ontology. It then asks education researchers and practitioners to instead use the theoretical framework of malinalli, the Aztec philosophical concept which best aligns with transformative social justice goals.  相似文献   
50.
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