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A new bandwidth allocation mechanism for next generation wireless cellular networks
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In this paper we design and study the performance of a Medium Access Control (MAC) scheme for the multiplexing and the integrated delivery of voice, mobile messaging, IP, gaming and H.264 videoconference traffic over a high-speed cellular TDMA channel with errors and capture. To the best of our knowledge, this is one of the first papers in the literature investigating the integration of actual H.264 video traces and gaming traffic with other types of traffic over wireless networks. Our results show that the proposed scheme achieves high throughput results while preserving the strict Quality of Service (QoS) requirements of each traffic type, and outperforms two efficient schemes previously proposed in the literature.
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... [1] Recently, with the emergence and rapid development of businesses related to ubiquitous networks, today in Korea different public institutions are pursuing such relevant projects to provide local-level ubiquitous network service. [2] Social stress contributes allegedly to the increasing occupancy rate of the patients addicted to drugs, including alcohol and narcotics, among mental patients. Such addiction patients change their emotions in a wider range even within a short period of time; for effective treatment, their daily routine data should be collected in a large volume and tracked to see the cycle of emotional change. ...
... The sensors exchange data in a ZigBee communication method between sensor nodes to send such collected data via a gateway server to the hospital where specialists conduct. [2,3] ...
Recently, with the rapid development of related ubiquitous industries, ubiquitous-Zone (u-Zone) development is being promoted to build a ubiquitous environment within a specific area. From a health care system perspective, in particular, u-Zone is expected to contribute to reducing cost and effort to manage patients’ condition such as in-patients, addiction patients and mental patients. In contrast, the current health care system only targets specific persons or continues to expand the internal system of hospitals. As addiction patients are on the rise in terms of drug addiction, including alcohol and narcotics, behavioural addiction attributable to the exposure to games, gambling, Internet and mobile communications and shopping is also becoming a problem. That is why it is difficult to collect data for the daily addiction status, which causes difficulties in systematic management and accurate diagnosis. Therefore, this paper suggests a remote measuring system to collect continuous condition data, which monitors the addiction patients via the vital sign measuring sensor within u-Zone. That is, the system collects their condition information from the sensors measuring heart rate, body temperature and acceleration, based on which the specialists determine the patient's emotional state. These data are expected to become the basis of diagnosing and managing addiction patients.
... Wireless Personal Area Network, which is abbreviated as WPAN, includes linkage between sensors and element technologies between sensors and networks. A larger ubiquitous network can be formed through connection to WLAN or CDMA network using the core technology of ubiquitous sensor networks [2] . In the medical field, the smartphone healthcare system that can transfer diagnosis data to patient's smartphone using healthcare systems has been applied. ...
In recent years, mobile healthcare systems that transfer patient data wirelessly have been used in the medical field. However, the current messages supported to patients are difficult to satisfy the specific patients, and there is a lack of healthcare systems to help manage patients with diabetes or pregnant women on a regular basis. In this regard, this paper demonstrates that the semantic-web service to which data transfer method, application framework and networking of WPAN are applied can be implemented. In addition, it suggests common data types to integrate data from a variety of sources and provides a common framework in which information on the Web can be shared and reused in applications, businesses and communities, etc. As an example, the healthcare monitoring that can manage healthcare for pregnant women, which includes confirmation of pregnancy, periodic health management, fetal movement, prenatal care and health-related knowledge, is proposed.
... According to the data of the National Health Insurance Corporation, the number of hospitals across the country was more than 82,300, that of medical personnel approximately 47 million, and that of admission days about 1 billion as of 2011, which indicates that the contents shown by above figures should be processed and kept in hospitals or pharmacies. [1] Thus, this paper proposes an order communication system using QR codes as a method to ensure the confidentiality of the prescription that contains sensitive information to its disclosure and store information efficiently. [2] This paper is composed of Chapter II. ...
With recent development in information technology, IT convergence has been achieved ubiquitously in all areas of industry. In particular, there have been a lot of changes in medical IT conversion sector in terms of user service. In this regard, this paper attempts to propose an environment in which the existing paper prescription can be transferred in the form of QR codes using mobile handsets as one of practices from the perspective of user service. QR codes can minimize the burden resulting from the process of the output, delivery and storage of paper prescriptions. In addition, they can utilize the representation of the information in a wide variety of ways, and they are considered to be media that can minimize the risk of personal information exposure and falsification due to the restoration and encryption of the information. Accordingly, the application of QR codes to the medical field is expected to improve confidentiality ad storage capability of the information, along with users' convenience.
... Ⅰ. 서 론 인기가 최근 급격히 증가하고 있는 멀티플레이어 게 임은 대부분 사람들과의 상호 작용이 포함되기 때문에 대역폭 관리 [1] 와 상태 일관성(consistency)에 대한 복잡 도 문제가 수반된다 [2] . 통신 대역폭 요건은 게임의 규모 [5] . ...
Multiplayer games typically organized based on a client-server(CS) or peer-to-peer(PP) architecture. The CS architecture is not scalable with the number of players due to a large bandwidth requirement at the server. The PP architecture, on the other hand, introduces significant overhead for the players, as each player needs to check the consistency between its local state and the state of all other players. We then propose a method that combines the merits of CS and PP. In this method, players exchange updates with lower priority in a peer-to-peer manner but communicate directly with a central server for the other updates. As a result, the proposed method has a lower network bandwidth requirement than the server of a CS architecture and the server bandwidth bottleneck is removed. For another important issue about multiplayer games, this method always maintains state consistency among players correctly. The performance of this method is evaluated through extensive simulation experiments and analysis.
... 통신망 기반의 클라이언트/서버 구조로 구성된다 [3] . [4,5] . [7,8] . ...
Multiplayer, real-time games are a kind of soft real-time systems because a game server has to respond to requests from many clients within specified time constraints. Client events have different timeliness and consistency requirements according to their nature in the game world. These requirements lead to different priorities on CPU processing. Events can be divided into different groups, depending on their consistency degree and priority. To handle these events with different priority and meet their timing constraints, we propose a priority-based group task scheduling policy in this paper. The number of clients or events requested by each client may be increased temporarily. In the presence of transient overloading, the game server needs to allocate more CPU bandwidth to serve an event with the higher priority level preferentially. The proposed scheduling policy is capable of enhancing real-time performance of the entire system by maximizing the number of events with higher priority completed successfully within their deadlines. The performance of this policy is evaluated through extensive simulation experiments.
This paper seeks to propose a senior living lab prototype based on the Internet of Things (IoT). Currently, IoT research is actively being conducted in various fields, and the field of IoT healthcare for elderly people is being highlighted with a rapid growth of ageing population. In this paper, a living lab platform was designed to recognize the movements of elderly people in real time and measure the quantity of motion by using Arduino's ultrasonic sensors and to help maintain a comfortable environment by using temperature & humidity sensors, which complemented the shortcomings of living lab based on the IoT healthcare.
In recent years, there has been a rapid development in ubiquitous related industries. Based on this trend, the development of U-Healthcare system has actively been promoted. In particular, a health status information system that can measure heath information of users through a real-time environmental and wireless method has been required. In this regard, this paper proposes a pulse measurement monitoring system can process health information and pulse measurement of a large number of hospitalized patients through a wireless pulse measuring instrument. The pulse of users is measured using the principle of Photo-PlethysmoGraphy, and health-related information of users can be identified through a mobile device after converting pulse status information into two-dimensional bar code for the switchover of analog signals to digital ones. In addition, visual information of pulse wave and expert opinions are provided through the MMS service.
Designing an effective and high performance network requires accurate characterization and modeling of network traffic. This paper provides a study of the transmission, modeling, and analysis of variable bit rate (VBR) video, which is fundamental for designing protocols and for effective utilization of networks in video transmission. To meet the specified requirements of future networks, the scalable video codec (SVC) was chosen as the video compression standard. The main objective of this work was to propose a statistical model that will allow better coordination between generated SVC video traffic and original video traffic. The performance of the proposed model was evaluated by comparing the model with three existing low-complex statistical models using graphical and statistical measurements as well as cross-validation. For all evaluation techniques, the accuracy of the proposed model was evaluated, and the frame size distribution of the modeled traffic was found to match that of the original video traffic better than other existing models. Copyright © 2015 John Wiley & Sons, Ltd.
This paper reveals the present status of wireless telemedicine system for m-health application. Wireless telemedicine network equipped with mobile, computer and telecommunication technologies which provide medical data, information and services from distant locations. Telemedicine opens a world of healthcare delivery by building clinical bridges between patients and available healthcare by integrating Information and Communication Technology, Biomedical Engineering, Medical Science, etc. using minimum costs, effective development and utilization of ancillary infrastructure and services. We have studied 130 research papers on telemedicine and its aspects, this paper is an extraction which emphasized on wireless technologies like GSM, General Packet Radio Services, EDGE, 3G, 4G, 5G, Cognitive Radio Network, World Wide interoperability of Microwave Access, Wireless Local Area Network, Wireless Body Area Network, Very Small Aperture Terminal, Satellite communication and WPAN (Bluetooth) used for m-health application. It also gives the details of storage, security, protocols, optimum bandwidth and fair scheduling schemes used for transmission of medical signals, images and videos.
Most of the multiplayer games available online are based on a client-server architecture because this architecture gives better administration control to the game providers than peer-to-peer architecture. In this architecture, the server is responsible for all the communication between the connected clients. The weakness of this architecture is its bandwidth requirement and scalability. Peer-to-peer architectures have then been proposed to solve these issues. In this paper, we propose a hybrid client-server architecture in which the game state is partially shared by the mobile terminal to achieve consistency among different players. Like a peer-to-peer architecture, this architecture uses client-side capacities to reduce bandwidth requirements for the server and improves consistency in wireless networks. Client events have different timeliness and consistency requirements according to their nature in the game world. These requirements lead to tasks with different priorities on CPU processing. In the proposed architecture, either the server or the client applies consistency mechanism according to the priority level. Simulation experiments show that the bandwidth of the server in this architecture is smaller than that of the client-server architecture. As a result, the server in the proposed architecture can accommodate more clients with enhancing the scalability.
We investigate pilot-symbol-aided parameter estimation for OFDM systems. We first derive a minimum mean-square error pilot-symbol-aided parameter estimator. Then, we discuss a robust implementation of the pilot-symbol-aided estimator that is insensitive to channel statistics. From the simulation results, the required SNRs for a 10% word error rate (WER) are 6.8 dB and 7.3 dB for the typical urban channels with 40 Hz and 200 Hz Doppler frequencies, respectively, and are 8 dB and 8.3 dB for the hilly-terrain channels with 40 Hz and 200 Hz Doppler frequencies, respectively. Compared with the decision-directed parameter estimator, the pilot-symbol-aided estimator is highly robust to Doppler frequency for dispersive fading channels with noise impairment even though it has some performance degradation for systems with lower Doppler frequencies
This chapter gives results from some illustrative exploration of the performance of information-theoretic criteria for model selection and methods to quantify precision when there is model selection uncertainty. The methods given in Chapter 4 are illustrated and additional insights are provided based on simulation and real data. Section 5.2 utilizes a chain binomial survival model for some Monte Carlo evaluation of unconditional sampling variance estimation, confidence intervals, and model averaging. For this simulation the generating process is known and can be of relatively high dimension. The generating model and the models used for data analysis in this chain binomial simulation are easy to understand and have no nuisance parameters. We give some comparisons of AIC versus BIC selection and use achieved confidence interval coverage as an integrating metric to judge the success of various approaches to inference.
Because of EMC problem PLC access networks have to operate with a limited signal power, which causes also reduction of available data rate. To be able to compete with other access technologies, PLC systems have to ensure a good network utilization and realization of different QoS guarantees. This can be provided by application of an efficient MAC layer. The investigation of MAC protocols for PLC has to be done under possibly realistic traffic models. For this purpose, we consider simple and multimodal source models, representing internet based data traffic, and apply them for investigation of different MAC protocols using per-packet reservation. Simulations under near to realistic traffic conditions confirm advantages of the two-step protocol, compared with extended ALOHA and extended polling reservation protocols. It is also concluded that the protocol performance depends mainly on the mean packet size and the mean interarrival time, defined in the traffic models.
We study the traffic generated by sessions of a popular multi-player network game. Our analysis indicates that empirical game traffic can be characterized well by certain analytical models. While clients and servers as well as hosts with different configurations, produce different models, all models from the game are well modeled by the same families of distributions. We find that some data sets are best modeled with split distributions; that is, one portion of the data is well modeled with one particular distribution, and the rest of the data with another. We describe how our models can be simulated and discuss how host processing speed influences packet interarrival processes, which in turn influence playability. The latter is a clear indication that end user quality of service is more than just a network issue-host characteristics must be considered as well. These are empirical results that have been rarely incorporated into theoretical analyses of network traffic. As Internet gaming becomes more popular, we expect that our models will be useful for testing hardware and protocols that support gaming.
We develop a model to quantify the performance of message transmission systems in which users must reserve transmission resources via a contention mechanism prior to transmission. Our work is motivated by a desire to understand the performance characteristics of systems such as the general packet radio service (GPRS), where the single forward link of the wireless access system is organized as a sequence of frames, each of which has first a contention period and then a service period. There are a fixed number of fixed-length contention slots in each contention period. Each contending customer chooses at random the slot in which to contend, and success is determined by a capture model. A contender who fails waits for the next contention period, then again chooses at random the slot in which to contend; this process is repeated until the contender is successful. Customers who have contended successfully are served during the service period, which has a prescribed number of fixed-length slots, on a first-come-first-served (FCFS) basis, with the required number of service units being drawn independently from a general discrete distribution having finite support. We model the system as a Markov renewal process embedded at service departure times. We solve the model and then compute the equilibrium distributions of the number of customers in the system at arbitrary points in time and at customer arrival times. Finally, we give a numerical example in which we demonstrate the usefulness of our results in understanding the behavior of GPRS.
Mainly deal with queueing models, but give the properties of many useful statistical distributions and algorithms for generating them.
Introduction One of the principal aims of cosmology is to identify the correct cosmological model, able to explain the available high-quality data. Determining the best model is a two-stage process. First, we must identify the set of parameters that we will allow to vary in seeking to fit the observations. As part of this process we need also to fix the allowable (prior) ranges that these parameters might take, most generally by providing a probability density function in the N-dimensional parameter space. This combination of parameter set and prior distribution is what we will call a model, and it should make calculable predictions for the quantities we are going to measure. Having chosen the model, the second stage is to determine, from the observations, the ranges of values of the parameters which are compatible with the data. This second step, parameter estimation, is described in the cosmological context by Lewis and Bridle in Chapter 3 of this volume. In this article, we shall concentrate on the choice of model. Typically, there is not a single model that we wish to fit to the data. Rather, the aim of obtaining the data is to choose between competing models, where different physical processes may be responsible for the observed outcome. This is the statistical problem of model comparison, or model selection. This is readily carried out by extending the Bayesian parameter estimation framework so that we assign probabilities to models, as well as to parameter values within those models.
H.264/MPEG-4 AVC is the latest international video coding standard. It was jointly developed by the Video Coding Experts Group (VCEG) of the ITU-T and the Moving Picture Experts Group (MPEG) of ISO/IEC. It uses state-of-the-art coding tools and provides enhanced coding efficiency for a wide range of applications, including video telephony, video conferencing, TV, storage (DVD and/or hard disk based, especially high-definition DVD), streaming video, digital video authoring, digital cinema, and many others. The work on a new set of extensions to this standard has recently been completed. These extensions, known as the Fidelity Range Extensions (FRExt), provide a number of enhanced capabilities relative to the base specification as approved in the Spring of 2003. In this paper, an overview of this standard is provided, including the highlights of the capabilities of the new FRExt features. Some comparisons with the existing MPEG-2 and MPEG-4 Part 2 standards are also provided.