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关键词： Games   Pricing   Social network services   Internet of Things   Computer science   Wireless networks   Edge computing   Backward induction   competition and cooperation   congestions   content service delivery   network effects   sponsored content   Stackelberg game  

摘要： A sponsored content policy enables a content provider (CP) to pay a network service provider (SP), and thereby mobile users (MUs) can access contents from the CP through network services from the SP with a lower charge. Thus, more users want to access the contents which potentially generates more profit gain to the CP. In this article, we study the interactions among three entities under the sponsored content policy, namely, the network SP, which is referred to as SP for brevity, the CP and MUs. We model the interactions as a hierarchical Stackelberg game, where the SP and the CP act as the leaders determining the pricing and sponsoring strategies, respectively, and the MUs act as the followers deciding on their content demand. The model incorporates the network effects in a social domain and congestion in a network domain which enables us to obtain insights from the sponsored content policy. In the model, we investigate the mutual interplay between the SP and the CP in three scenarios: 1) sequential competition, where the SP first optimizes its pricing strategy for maximizing its revenue, and then the CP optimizes its sponsoring strategy for maximizing its profit sequentially;2) simultaneous competition, where the CP and the SP optimize their individual strategies separately and simultaneously;and 3) cooperation, where both providers jointly optimize their strategies with the purpose of maximizing their aggregate payoff. Through backward induction, we derive the unique Nash equilibrium among the MUs. Furthermore, the existence and uniqueness of the Stackelberg equilibrium under three proposed scenarios are validated analytically. Via extensive simulations, it is shown that the network effects significantly improve the utilities of MUs, the profit of the CP, and the revenue of the SP.

关键词： Computer science   conceptions of learning   approaches to learning   individual differences  

摘要： The purpose of this research was to examine college students' conceptions of learning computer science and approaches to learning computer science and to examine the relationships among these two important constructs and possible moderating factors. Student data (N = 193) were collected using the conceptions of learning computer science and the approaches to learning computer science surveys at one public research institution in the southeastern United States. Data were analyzed with descriptive statistics, Confirmatory Factor Analysis models, internal consistency reliability, Pearson correlations, stepwise multiple regression models, and Multivariate Analysis of Variance models. The results suggest that college students most favorably employ a deep strategy approach for learning computer science in which prior knowledge is activated and meaningful learning strategies are used. College students appear to be more extrinsically motivated to learn computer science than intrinsically. Higher level learning conceptions are associated with a deep strategy approach to learning (e.g., Seeing in a new way) whereas low-level conceptions are associated with a surface strategy (e.g., Memorizing) approach to learning. Male college students have slightly higher conceptions of programming than their female counterparts. The findings are discussed and both limitations and delimitations of the study are enumerated.

关键词： Neuroscience   Computer science   Computer in education   Human-centered computing   Human machine interaction   Social sciences   Psychology   Mental health   Psychological disorders   Well-being   Virtual reality   Asperger's syndrome   VR illusions   Empathy   Constructivist approach  

摘要： The immense capabilities provided by virtual reality for enhancing empathy and altering social behaviors, make it possible to use virtual reality for the promotion of the understanding between individuals. A social issue that needs to be addressed is the discrimination and marginalization of people with Asperger's syndrome (AS) from the working force, stemming from the lack of recognition and justi fication of their oddities. In this paper, the effectiveness of a virtual reality simulation, raising awareness on this speci fic issue, is evaluated. Awareness is a term used in this research to refer to the combination of conceptual knowledge and sensitization on a speci fic issue. An experiment with between -group design has been carried out, where half of the participants used the simulation via a VR headset device and the other half was given a transcript of relevant medical articles instead. The comparison between the two groups indicates that the group which used the simulation gained more knowledge on AS than the group which used the transcript. Moreover, the parameter of sensitization indicates positive correlations with place illusion in the VR group.

关键词： Ecosystems   Data models   Machine learning   Delays   Computer science   IEEE transactions   Economics   Mobile virtual network operator (MVNO)   mobile network operator (MNO)   base carrier   MVNO ecosystem  

摘要： Recent years have witnessed the rapid growth of mobile virtual network operators (MVNOs), which operate on top of existing cellular infrastructures of base carriers, while offering cheaper or more flexible data plans compared to those of the base carriers. In this paper, we present a two-year measurement study towards understanding various fundamental aspects of today's MVNO ecosystem, including its architecture, customers, performance, economics, and the complex interplay with the base carrier. Our study focuses on a large commercial MVNO with one million customers, operating atop a nation-wide base carrier. Our measurements clarify several key concerns raised by MVNO customers, such as inaccurate billing and potential performance discrimination with the base carrier. We also leverage big data analytics, statistical modeling, and machine learning to address the MVNO's key concerns with regard to data usage prediction, data plan reselling, customer churn mitigation, and billing delay reduction. Our proposed techniques can help achieve higher revenues and improved services for commercial MVNOs.

关键词： Random access memory   Routing   Indexes   Access control   Topology   Memory management   Computer science   Enterprise network   forwarding table structure   routing policy  

摘要： With increasing demands for more flexible services, the routing policies in enterprise networks become much richer. This has placed a heavy burden to the current router forwarding plane in support of the increasing number of policies, primarily due to the limited capacity in TCAM, which further hinders the development of new network services and applications. The scalable forwarding table structures for enterprise networks have therefore attracted numerous attentions from both academia and industry. To tackle this challenge, in this paper we present the design and implementation of a new forwarding table structure. It separates the functions of TCAM and SRAM, and maximally utilizes the large and flexible SRAM. A set of schemes are progressively designed, to compress storage of forwarding rules, and maintain correctness and achieve line-card speeds of packet forwarding. We further design an incremental update algorithm that allows less access to memory. The proposed scheme is validated and evaluated through a realistic implementation on a commercial router using real datasets. Our proposal can be easily implemented in the existing devices. The evaluation results show that the performance of forwarding tables under the proposed scheme is promising.

关键词： Computer science   Electrical engineering   Nanotechnology   Physics methods   Computer-aided design   Semiconductors   Leakage   Standard cells   Mathematical modelling   Design   Liberty file   JAVA  

摘要： In the most advanced technology nodes, leakage has become a major concern for integrated circuits designers. In addition, the leakage calculation using SPICE simulations takes a large amount of time for the entire library of standard cells for the different PVT (Process, Voltage, and Temperature) conditions. However IC Designers usually need a fast access to the leakage current estimation in order to validate their designs. In this context, the present paper proposes a new approach of the leakage estimation. The aim of this methodology is to predict the leakage of a standard cell accurately and in a short amount of time. This method is applied to all the cells of the used standard cell library and is based on mathematical models developed from the leakage physical equation. The results of the leakage calculated with this technique shows an average error of 5%. The context of this work is part of a fast generation of a full liberty file of a standard cell library using the curve fitting method.

关键词： Heuristic algorithms   Benchmark testing   Optimization   Shape   Scalability   Cybernetics   Computer science   Adversarial examples   dynamic multiobjective optimization (DMO)   dynamics   Pareto front   scalable test problems  

摘要： Dynamic multiobjective optimization (DMO) has gained increasing attention in recent years. Test problems are of great importance in order to facilitate the development of advanced algorithms that can handle dynamic environments well. However, many of the existing dynamic multiobjective test problems have not been rigorously constructed and analyzed, which may induce some unexpected bias when they are used for algorithmic analysis. In this paper, some of these biases are identified after a review of widely used test problems. These include poor scalability of objectives and, more important, problematic overemphasis of static properties rather than dynamics making it difficult to draw accurate conclusion about the strengths and weaknesses of the algorithms studied. A diverse set of dynamics and features is then highlighted that a good test suite should have. We further develop a scalable continuous test suite, which includes a number of dynamics or features that have been rarely considered in literature but frequently occur in real life. It is demonstrated with empirical studies that the proposed test suite is more challenging to the DMO algorithms found in the literature. The test suite can also test algorithms in ways that existing test suites cannot.

关键词： Bidirectional gated recurrent unit   Abstract sentence classification   Deep learning   Crowdsourcing  

摘要： The automatic classification of abstract sentences into its main elements (background, objectives, methods, results, conclusions) is a key tool to support scientific database querying, to summarize relevant literature works and to assist in the writing of new abstracts. In this paper, we propose a novel deep learning approach based on a convolutional layer and a bidirectional gated recurrent unit to classify sentences of abstracts. First, the proposed neural network was tested on a publicly available repository containing 20 thousand abstracts from the biomedical domain. Competitive results were achieved, with weight-averaged Precision, Recall and F1-score values around 91%, and an area under the ROC curve (AUC) of 99%, which are higher when compared to a state-of-the-art neural network. Then, a crowdsourcing approach using gamification was adopted to create a new comprehensive set of 4111 classified sentences from the computer science domain, focused on social media abstracts. The results of applying the same deep learning modeling technique trained with 3287 (80%) of the available sentences were below the ones obtained for the larger biomedical dataset, with weight-averaged Precision, Recall and F1-score values between 73 and 76%, and an AUC of 91%. Considering the dataset dimension as a likely important factor for such performance decrease, a data augmentation approach was further applied. This involved the use of text mining to translate sentences of the computer science abstract corpus while retaining the same meaning. Such approach resulted in slight improvements (around 2 percentage points) for the weight-averaged Recall and F1-score values.