Based on the computer simulations the potential effect of various systems for reduction of guiding forces in track curves for electric locomotives was compared. From this comparison, the greatest potential is shown by...
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the research of automatic recognition of machining features constitutes a crucial supporting pillar for intelligent design and manufacturing. Despite the availability of existing algorithms, there are prevalent proble...
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We consider the over-time version of the MAX-MIN FAIR ALLOCATION problem. Given a time horizon t = 1, 2,..., T, with at each time t a set of demands and a set of available resources that may change over the time defin...
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ISBN:
(纸本)9781450356497
We consider the over-time version of the MAX-MIN FAIR ALLOCATION problem. Given a time horizon t = 1, 2,..., T, with at each time t a set of demands and a set of available resources that may change over the time defining instance I-t, we seek a sequence of solutions S-1, S-2,, S-T that (1) are near-optimal at each time t, and (2) as stable as possible (inducing small modification costs). We focus on the impact of the knowledge of the future on the quality and the stability of the returned solutions by distinguishing three settings: the off-line setting where the whole set of instances through the time horizon is known in advance, the on-line setting where no future instance is known, and the k-lookahead setting where at time t, the instances at times t + 1,, t + k are known. We first consider the case without restrictions where the set of resources and the set of agents are the same for all instances and where every resource can be allocated to any agent. For the off-line setting, we show that the over-time version of the problem is much harder than the static one, since it becomes NP-hard even for families of instances for which the static problem is trivial. then, we provide a rho/rho+1-approximation algorithm for the off-line setting using as subroutine a rho-approximation algorithm for the static version. We also give a rho/rho+1-competitive algorithm for the online setting using also as subroutine a p-approximation algorithm for the static version. Furthermore, for the case with restrictions, we show that in the off-line setting it is possible to get a polynomial-time algorithm withthe same approximation ratio as in the case without restrictions. For the online setting, we prove that it is not possible to find an online algorithm with bounded competitive ratio. For the 1-lookahead setting however, we give a rho/2(2 rho +1) approximation algorithm using as subroutine a rho-approximation algorithm for the static version.
In this paper we propose two associative parallel algorithms for the edge update of a minimum spanning tree when an edge is deleted or inserted in the underlying graph. these algorithms are represented as the correspo...
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E-learning is recently days considered the easy media used to teach materials and courses. the E-learning environment contains a lot of resources and content related to each user profile. those contents are considered...
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Predicting students' academic performance has long been an important research topic in many academic disciplines. the prediction will help the tutors identify the weak students and help them score better marks;the...
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ISBN:
(纸本)9789897580208
Predicting students' academic performance has long been an important research topic in many academic disciplines. the prediction will help the tutors identify the weak students and help them score better marks;these steps were taken to improve the performance of the students. the present study uses free style comments written by students after each lesson. these comments reflect their learning attitudes to the lesson, understanding of subjects, difficulties to learn, and learning activities in the classroom. (Goda and Mine, 2011) proposed PCN method to estimate students' learning situations from their comments freely written by themselves. this paper uses C (Current) method from the PCN method. the C method only uses comments with C item that focuses on students' understanding and achievements during the class period. the aims of this study are, by applying the method to the students' comments, to clarify relationships between student's behaviour and their success, and to develop a model of students' performance predictors. To this end, we use Latent Semantic Analyses (LSA) and K-means clustering techniques. the results of this study reported a model of students' academic performance predictors by analysing their comment data as variables of predictors.
Positive user experience (UX), including its pragmatic and hedonic aspects, is a central design target for interactive products and services. Increasingly, Web services are developed for both PCs and mobile terminals ...
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ISBN:
(纸本)9781605582474
Positive user experience (UX), including its pragmatic and hedonic aspects, is a central design target for interactive products and services. Increasingly, Web services are developed for both PCs and mobile terminals to support user needs for media content management and social interaction. Even though many UX models have been developed over the last decade, the specific characteristics affecting UX of Web services have not been studied systematically. In this paper we present the first phase of our service UX study in which three Web services were evaluated by three UX experts each, using an initial set of service UX evaluation heuristics. We discuss how well these heuristics covered the positive and negative service UX evaluation findings, and how the heuristics and the expert evaluation approach of UX should be developed further.
A key issue in artificial intelligence methods for interactive preference elicitation is choosing at each stage an appropriate query to the user, in order to find a near-optimal solution as quickly as possible. A theo...
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Presently across the world, financial institutions strive tremendously hard to make financial services smarter to benefit from the advantages of digitization. To enhance client services, financial technology (Fintech)...
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