Byunghun Song

Surveillance Tracking System Using Passive Infrared Motion Sensors in Wireless Sensor Network

Wireless Sensor Networks for surveillance systems in home, office, or factory environment require correct tracking of intruders. For such systems, passive infrared motion sensors (PIR sensors) are ideal because they do not require any signal or devices on the object to be tracked and they can work in dark environment as well. This paper first analyzes the performance and the applicability of the PIR sensors for security systems. Then, we propose a region-based human tracking algorithm with actual implementation and experiment in real environment. From the experiments, we show that the human tracking algorithm based on the PIR sensors performs very well with proper sensor deployment.

MRED: a new approach to random early detection

In order to reduce the increasing packet loss rates caused by an exponential increase in network traffic, the IETF (Internet Engineering Task Force) is considering the deployment of active queue management techniques such as RED (random early detection). While active queue management in routers and gateways can potentially reduce packet loss rates in the Internet, this paper has demonstrated the inherent weakness of current techniques and shows that they are ineffective in preventing high loss rates. The inherent problem with these queue management algorithms is that they all use queue lengths as the indicator of the severity of congestion. In order to solve this problem, a new active queue management algorithm called MRED is proposed. MRED computes the packet drop probability based on our heuristic method rather than the simple method used in RED. Using simulation, MRED is shown to perform better than existing queue management schemes.

SRTP: TCP-Friendly Congestion Control for Multimedia Streaming

Multimedia streaming applications are becoming increasingly popular on the Internet. Most of these applications do not share the available bandwidth fairly with applications built on TCP, such as webb rowsers, FTP- or email-clients. The Internet community strongly fears UDP-based multimedia applications, because the UDP traffic could lead to a congestion collapse and starvation of TCP traffic. For this reason, TCP-friendly protocols are being developed that behave fairly with respect to co-existent TCP flows. In this paper, we propose a new TCP-friendly protocol, called Smart RTP(SRTP), for multimedia streaming. Our proposed protocol has two salient features. One is TCP-friendliness and the other is rate smoothness. As a result, the end-to-end quality of service (QoS) is improved. The evaluation results demonstrate the effectiveness of our proposed schemes.

Energy-Aware Pipeline Monitoring System Using Piezoelectric Sensor

A pipeline can be damaged through a variety of ways and means. If the pipeline damage is directly connected to safety problems, an urgent need to continuously monitor the pipeline exists. For such continuous monitoring, a wireless sensor network has recently been regarded as a solution. However, existing techniques consume a large amount of energy, it is therefore very hard in practice to employ sensor nodes that have limited energy resources. In this paper, we propose a pipeline monitoring system based on piezoelectric sensors to replace the existing high-power-consuming sensing system. The system consists of wireless impedence nodes that are operated with energy-aware software techniques. The experiments conducted in a real pipeline test bed show that the proposed system, indeed, detects pipeline structural deformation and also manages the monitoring system continuously with a guaranteed operation time.

The Method of Location Error Detection and Correcting in Smart Home Environments

The location awareness system is an essential factor for the development of low cost sensor networks for use in the smart home environments and ubiquitous networking. This paper addresses the problem of tracking a moving intelligent robot using the pharos indoor location system. Our motivating applications include intelligent robot navigation, where location sensors provide position information to a moving robot. All of these applications require the position of a device moving at human speeds to be tracked. Ubiquitous indoor environments often contain substantial amounts of metal and other such reflective materials that affect the propagation of radio frequency signals in non-trivial ways, causing severe multi-path effects, dead-spots, noise, and interference. In this paper, we address the location error detection and correcting problems of the sensor network platform with RF and ultrasonic for location tracking system. Especially we present a novel detecting error of location and correcting using LQI that is particularly well suited to support context-aware smart home computing. It is achieved by considering the speed variance of the moving object and the corrected the interference errors. This proposed scheme applied the method of an error correct to the mobile object. We brought a 5% efficiencies comparing with a three existing schemes (listener inference algorithm). And The system called Pharos, aims to combine the advantages of real-time tracking systems that implement distributed environment with regardless of infrastructure or infrastructure-less wireless sensor networks.

On Efficient SC-Based Soft Handoff Scheme in Proxy Mobile IPv6 Networks

This study examines mobility support functions in soft handoff and IP-based mobile network, and distinguishes the control areas in the cell’s range areas. Several important characteristics of cell configurations for soft handoff are used to propose new structures for mobile network’s efficient session control (SC). A fixed-point strategy is proposed in order to not only determine the handoff traffic’s arrival speed, but stably calculate the loss probabilities or set the optimum guard channel numbers. We suggest a False Handoff Sessions (FHS) for improving the channel use efficiency based on mobility information. Numerical analyses indicate the efficiency of the presented Markov chain model and the advantage of proposed soft handoff method.

Prioritized Multipath Video Forwarding in WSN

The realization of Wireless Multimedia Sensor Networks (WMSNs) has been fostered by the availability of low cost and low power CMOS devices. However, the transmission of bulk video data requires adequate bandwidth, which cannot be promised by single path communication on an intrinsically low resourced sensor network. Moreover, the distortion or artifacts in the video data and the adherence to delay threshold adds to the challenge. In this paper, we propose a two stage Quality of Service (QoS) guaranteeing scheme called Prioritized Multipath WMSN (PMW) for transmitting H.264 encoded video. Multipath selection based on QoS metrics is done in the first stage, while the second stage further prioritizes the paths for sending H.264 encoded video frames on the best available path. PMW uses two composite metrics that are comprised of hop-count, path energy, BER, and end-to-end delay. A colorcoded assisted network maintenance and failure recovery scheme has also been proposed using (a) smart greedy mode, (b) walking back mode, and (c) path switchover. Moreover, feedback controlled adaptive video encoding can smartly tune the encoding parameters based on the perceived video quality. Computer simulation using OPNET validates that the proposed scheme significantly outperforms the conventional approaches on human eye perception and delay. Keywords—WMSN, H.264, Multiple Paths, Quality of Service

On Cross-Layer Based Handoff Scheme in Heterogeneous Mobile Networks

The necessities of the MNs are generally included in the cellular modules available in LTE/3G and Wi-Fi for high-speed Internet. Further, many people with Wi-Fi and LTE/3G use a cross-layer-based handoff as they move from one place to another. MN mobility management has been handled adequately; however, using the network-based mobility management described in this paper, carriers can manage and maintain a lower-cost network.

Multi-Channel Multi-Path video transmission over wireless sensor networks

Recently, various applications have emerged which utilize wireless sensor network (WSN) consisting of low cost and low power sensors in smart spaces. Here a great deal of research has been carried out on transmitting video over WSN. WSN has limited resources in terms of bandwidth and data processing capability, while video requires bulk data to be transmitted. In this paper we propose a two-stage Quality of Service (QoS) guaranteeing scheme for video transmission over WSN, called the Multi-Channel Multi-Path (MCMP) scheme. It selects the best paths from the source camera to the gateway based on hop-count, aggregated path energy, BER, and end-to-end delay. A failure recovery scheme is also provided to cope with link failure. Computer simulation reveals that the proposed scheme significantly outperforms the existing scheme in terms of channel utilization and delay.

Design of Smart Factory Web Services Based on the Industrial Internet of Things

The Industrial Internet of Things (IIoT) is cited as the latest means for making manufacturing more flexible, cost effective, and responsive to changes in customer demands. However, a major concern surrounding the IIoT is interoperability between devices and machines that function within different protocols and architectures. This paper presents the Smart Factory Web (SFW), which is based on the IIoT concept of improving factory-to-factory interoperability. The proposed SFW enables secure data and service integration in cross-site application scenarios as well as ‘plug & work’ functions for devices, machines, and data analytics software by applying industrial standards, Open Platform Communications Unified Architecture (OPC UA), and Automation Markup Language (AutomationML) . To reach the goal, experimental factories that have heterogeneous manufacturing infrastructures are linked and the SFW is implemented in four phases. The usage scenario, called order-driven adaptive production, used to align capacity across factories, will also be validated in the real deployment .