Multidimensional Scalability Research Articles

Policy Optimization of the Power Allocation Algorithm Based on the Actor–Critic Framework in Small Cell Networks

A practical solution to the power allocation problem in ultra-dense small cell networks can be achieved by using deep reinforcement learning (DRL) methods. Unlike traditional algorithms, DRL methods are capable of achieving low latency and operating without the need for global real-time channel state information (CSI). Based on the actor–critic framework, we propose a policy optimization of the power allocation algorithm (POPA) for small cell networks in this paper. The POPA adopts the proximal policy optimization (PPO) algorithm to update the policy, which has been shown to have stable exploration and convergence effects in our simulations. Thanks to our proposed actor–critic architecture with distributed execution and centralized exploration training, the POPA can meet real-time requirements and has multi-dimensional scalability. Through simulations, we demonstrate that the POPA outperforms existing methods in terms of spectral efficiency. Our findings suggest that the POPA can be of practical value for power allocation in small cell networks.

Data reorganization for scalable video service with embedded mobile devices

Recent development of high-speed wireless networks and embedded systems has enabled the recording and delivery of high-performance multimedia to heterogeneous mobile users. To support heterogeneous mobile users with high-quality multimedia services, scalable video coding was introduced. In the scalable video coding (SVC), through multidimensional scalability, all types of these scalability can be exploited at the same time. However, the generated video sequences of scalable video coding are not adequate for mobile multimedia service systems since its flexibility makes non contiguous storing and retrieval of partial stream data. In this article, we propose efficient scalable video data reorganization for video servicing systems, which consist of video server and mobile clients. For video server, we reorganize scalable video streams taking into account both of decoding dependency and location in disk array storage, where disk array is widely used for storage systems of video server. In the mobile devices, we place substreams with the consideration of NAND flash memory page and block boundaries, which is storage for mobile devices. The experimental results show that the proposed reorganization of scalable video can improve the performance of mobile multimedia service systems.

Quality assessment of multidimensional video scalability

Scalability is a powerful concept for adaptive video content delivery to many end users having heterogeneous and dynamic characteristics of networks and devices. In order to maximize users' quality of experience by selecting appropriate combinations of multiple scalability parameters, it is crucial to understand and model the relationship between multidimensional scalability and perceived quality. In this article, we address the latest advances in subjective and objective quality evaluation of multidimensional video scalability for optimal content distribution, present their applications, and discuss future trends and challenges.

A Wireless Sensor Network Architecture for Diversiform Deployment Environments

Network architecture is the foundation of network system. Wireless sensor networks (WSN) are always concentrated some key technologies under specific applications, and some prototype systems are developed according to specific applications of environments, but the research on WSN architecture is relatively weak currently. WSN is a highly complex distributed system, the defects in traditional WSN architectures are firstly studied, then the typical requirement objectives of WSN are acquired by analysis, and a set of design principles for WSN model is concluded. Because the WSN is mostly intended for variable and inhospitable environments, where persistent and continuous energy supply is lacking, the environment adaptive and energy efficient capabilities are integrant for WSN architecture. According with other objectives scalability and service-customized, an environment adaptive, energy efficient, hierarchical structure and sub-facets functions architecture model of WSN (EAWNA) is proposed. Furthermore, the design methods, general characteristics and functions of every lay or every module are described and discussed. At last, from the abstract levels of component framework, EAWNA is described formally besides all component layers entities are defined. EAWNA has not only the double characteristics: environment adaptive and energy efficient, but also has the traits such as multi-dimensional scalability, service-customized, and cross-layer interaction. EAWNA model can supply a theoretical framework and a kind of unified description method for diversified protocols in WSN.

Multidimensional Factor-Analysis-Based Procedures for Assessing Scalability in Personality Measurement

Most personality tests are made up of Likert-type items and analyzed by means of factor analysis (FA). In this type of application, the fit of the model at the level of individual respondents is almost never assessed. This article proposes procedures for assessing individual fit (scalability). The procedures are intended for the analysis of multitrait personality questionnaires, and based on the multiple FA model. A general assessment procedure is described, and 2 multidimensional scalability indexes that use the chi-square and normal distribution are proposed. These indexes are derived both as residual measures and as likelihood-based person-fit measures, and their relations with some item-response, theory-based measures is discussed. The indexes are proposed mainly as first-step exploratory devices, and procedures for obtaining further information about the possible causes of misfit are also discussed. The behavior of the indexes is assessed in simulation studies, and the general procedure is illustrated by means of an empirical example.

Analysis and case study on multi-dimensional scalability of the Internet architecture

This paper presents the definition of multi-dimensional scalability of the Internet architecture, and puts forward a mathematical method to evaluate Internet scalability based on a variety of constraints. Then, the method is employed to study the Internet scalability problem in performance, scale and service scalability. Based on the examples, theoretical analysis and experimental simulation are conducted to address the scalability issue. The results show that the proposed definition and evaluation method of multi-dimensional Internet scalability can effectively evaluate the scalability of the Internet in every aspect, thus providing rational suggestions and methods for evaluation of the next generation Internet architecture.