37867207
A Low-Latency Peer-to-Peer Approach for Massively Multiplayer Games
This paper focuses on the latency reduction problem in massively multiplayer games (MMGs). As the client-server (CS) architecture in use today in most commercial MMGs applications are exposing its weakness in scalability as the number of players increases, researchers start to consider the peer-to-peer (P2P) model that has inherent high scalability for MMGs. However, existing P2P models generally lead to high latency that significantly detracts from the playing experience. To improve this, we present a novel communication model intended to reduce the latency of network communication on game states. The model, based on DHT protocol, can select the best candidate node to perform server's role for a game zone. In contrast, existing P2P models designate 'peer servers' randomly without considering latency effects. The simulation shows that our approach obtains much lower latency than existing P2P models. The performance of our approach is shown to be even better than that of CS models.
1622406
Structure Analysis and SNR-Variance Evolution for Parallel Concatenated Coded IDMA Systems
This paper is concerned with parallel concatenated coded interleave-division multiple-access (IDMA) systems. We briefly present the transmitter/receiver structure of these systems and propose an efficient SNR-variance evolution scheme for bit-error-rate (BER) performance evaluation. The proposed evolution scheme is also useful for system performance optimization. Numerical results show that the BER performance curves obtained by simulation and evolution are quite close when the data length is long enough.
39099940
Efficient error recovery techniques in a novel multimedia streaming framework with peer-paired collaboration
Recently, active research has gone to application-level multicast that tries to bring all the merits of unicast and IP multicast together while avoiding their drawbacks. How to efficiently recover from errors in such a system is a difficult question yet to be answered. The current research focus is primarily on developing local error recovery techniques, but these techniques would not work in case of shared losses, which often occur in application-level multicast. In this paper, a novel multimedia streaming framework called peer-paired pyramid streaming (P/sup 3/S) is proposed. It is basically a hybrid client/server and peer-to-peer structure. In P/sup 3/S, clients are hierarchically organized and those at the same level are coupled and peer-pairs are then formed. Based on P/sup 3/S, we introduce some controlled delay between packets that are vulnerable to shared losses to combat with the shared losses. The proposed technique is supported by both theoretical and experimental results presented in this paper.
15663663
Kernel based articulated object tracking with scale adaptation and model update
Kernel based object tracking (KBOT) is one of the most popular and effective techniques for tracking task. However the constancy of the target model and unsound scale adaptation method are two main limitations. In this paper, we present a kernel based approach incorporated with scale estimation and target model update for articulated object tracking task. After predicating the object center with scale fixed KBOT, we extend scale selection theory to estimate the local optimal object scale. Once the object scale has been estimated, a kernel density estimation based strategy is developed to update the target model. Experimental results show that our approach is superior to traditional KBOT in the following two aspects: 1) it is less affected by the object scale change; 2) it is less prone to appearance variation.
38177882
A Hybrid Feature Selection Approach for Microarray Gene Expression Data
Due to the huge number of genes and comparatively small number of samples from microarray gene expression data, accurate classification of diseases becomes challenging. Feature selection techniques can improve the classification accuracy by removing irrelevant and redundant genes. However, the performance of different feature selection algorithms based on different theoretic arguments varies even when they are applied to the same data set. In this paper, we propose a hybrid approach to combine useful outcomes from different feature selection methods through a genetic algorithm. The experimental results demonstrate that our approach can achieve better classification accuracy with a smaller gene subset than each individual feature selection algorithm does.
16868039
Automatic text discovering through stroke-based segmentation and text string combination
In this paper we present a novel framework of automatic text discovering for content-based multimedia application. For single image, the stroke-based binarization and the coarse-to-fine text extraction will collaborate to generate a clean text image for recognition. For image sequence, multi-frame text enhancement is adopted to increase the text/background contrast, and the recognition results are finally refined by the text string combination algorithm to get more precise semantic information. Two prototype demos have been successfully developed on mobile phones. The experimental results on different platforms show the superior performance of the proposed method.
5494803
Wireless Network Dynamic Topology Routing Protocol Based on Aggregation Tree Model
As the scale of the network increases, especially wireless and mobile networks comes into fashion, the problem of network dynamic topology management turns into a focus topic in the network world. When network information changes, frequent route computing and network state updates can cause computing and traffic overhead, respectively. Therefore, minimum of influence to network structure has been identified as one of the key issues in designing dynamic network routing protocols. A novel protocol, which is based on Aggregation Tree Routing Model (ATRM) as well as an effective ball-and-string algorithm, is introduced in this paper which aims to minimize the alteration of network topology and to speed up the minimum cost route computation. This routing protocol is applicable to all kinds of networks, including Internet, ad hoc and wireless sensor networks. The simulations show that our protocol not only results in significantly lower overhead, but also gives high levels of dynamic network topology management performance while keeping practical.
15004157
A Semantic QoS-Aware Discovery Framework for Web Services
Augmenting web services with explicit semantics forms the foundation of Service Oriented Architectures (SOAs) automation. As more and more Semantic Web Services (SWSs) are deployed, similar SWSs could have quite different quality-of-service (QoS) levels. The QoS-aware discovery becomes an important challenge. While some efforts try to solve it via Constraint Programming (CP), they suffer from the purely syntactic matchmaking method. Furthermore, the construction of constraints and the selection of services are completely dependent on the literal translation from QoS descriptions, which increase obstacles to actually apply CP. In this paper, we propose a semantic QoS-aware framework for SWSs discovery by combining the semantic matchmaking and CP. Initially, a QoS ontology is presented to define QoS data into service descriptions. Then the ontology reasoning is adopted to change previous syntactic matchmaking into a semantic way. Through confirming the compatibility of concepts, complex QoS conditions are solved as constraints and a selection algorithm is proposed to obtain the optimal offer. Finally, the prototype implementation of our framework is discussed and a SWSs discovery case is used to illustrate the comprehensive discovery process.
6984424
Ontology-based security assessment for software products
This paper proposes an ontology-based approach to analyzing and assessing the security posture for software products. It provides measurements of trust for a software product based on its security requirements and evidence of assurance, which are retrieved from an ontology built for vulnerability management. Our approach differentiates with the previous work in the following aspects: (1) It is a holistic approach emphasizing that the system assurance cannot be determined or explained by its component assurance alone. Instead, the software system as a whole determines its assurance level. (2) Our approach is based on widely accepted standards such as CVSS, CVE, CWE, CPE, and CAPEC. Our ontology integrated these standards seamlessly thus provides a solid foundation for security assessment. (3) Automated tools have been built to support our approach, delivering the environmental scores for software products.