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We proposed a silicon-on-insulator (SOI) based coplanar dual gate ion-sensitive field-effect transistor (Cop-DG-ISFET) pH sensor to improve the performance of conventional ISFET pH sensors. Cop-DG-ISFET employs coplanar dual gates consisting of a control gate (CG) and a sensing gate (SG) over the channel, and a floating gate (FG) under the channel. Since CG and SG are capacitively coupled to FG, both gates can be used to modulate FET channel conductance. As a result, this device can amplify the sensing signal according to the capacitive coupling ratio between FG and coplanar gates (CG or SG). Since the amplification factor can be adjusted by the capacitance ratio of SG and CG, the pH sensitivity is improved by reducing the CG area compared to the SG area. Moreover, we evaluated the stability of the device by measuring the hysteresis width and drift rate, and found the stability was improved when the sensitivity was taken into consideration. Therefore, the SOI-based Cop-DG-ISFET sensor is expected to be a promising point-of-care biosensor application platform with a simple structure and excellent sensitivity and stability.

For efficient IoT mobility management, CoAP-based mobility management protocol (CoMP) was proposed to counteract constraints of mobility internet protocol version 6 (MIPv6). CoMP exchanges Binding Update (BU) messages to manage location changes but the BU messages are subjected to security vulnerabilities like denial of service (DoS), false BU, session hijacking, and man in the middle (MITM) attacks. In this paper, we extend CoMP by proposing a security scheme based on a private key to protect the BU CoMP messages exchanged between the mobile nodes and clients referred to as PKBU-CoMP (private key-based BU for CoMP). PKBU-CoMP ensures that clients check address ownership and validity of mobile nodes before performing any BU operation. A detailed signalling flow diagram was designed, and we conducted a performance analysis of the PKBU-CoMP.

The spry maturation of Internet of Things (IoT) has paved way to the rapid development of numerous sectors and these have been envisioned in; connected transport, smart cities, connected homes, connected healthcare, etc. IoT is a technology that connects "things" that are embedded with sensors, actuators and network connectivity to collect and exchange the data to the internet. The ability of IoT that offers distinct technologies for a small constrained device to collect and deliver messages across sophisticated networks leaves room for more exploration. Zeroing down to the healthcare sector, a couple of Personal Health Devices (PHDs) have been developed to collect and share information across the internet. One Machine to Machine (oneM2M), ISO/IEEE 11073 PHD are some of the healthcare standards that have been developed have been developed to deal with the issue of interoperability in the IoT. In this paper we design and implement an interoperable messaging system that is based on international standards for IoT healthcare services. Standard IoT protocols; Message Queuing Telemetry Transport (MQTT) and Constrained Application Protocol (CoAP) are some of the protocols that were designed to be used in an IoT environment. We designed and implemented a message system using CoAP following international standards for IoT healthcare services. This is due to better performance that CoAP offers in a constrained environment over other protocols. The paper further analyses and evaluates a comparative performance of number of packets transmitted in a transaction and packet loss rate number during transmission between the designed system and existing messaging system that uses MQTT.

Non-oriented electrical steels are widely used as core material of electrical machinery such as motors and generators. Manufacturing process such as punching and shearing is needed to produce the core with non-oriented electrical steels, but the stress induced unavoidably during the manufacturing process makes the magnetic property of core is severely deteriorated. Stress relief annealing treatment, therefore, is commonly applied to remove the harmful effect of internal residual stress in the processed core. In this paper, the effect of stress relief annealing temperature and atmosphere on microstructure and magnetic properties of fully processed non-oriented electrical steels with different grades were investigated. Cut samples were prepared by shearing and submitted to stress relief annealing with various temperature (650∼850°C) and H 2 gas ratio in atmosphere (0∼30%). It was found that core loss of sample is improved as temperature increases from 650 to 850°C, while the magnetic flux density is deteriorated with increase of annealing temperature. Decrease of core loss was reasoned by grain size coarsening and shows some different tendency between samples, while decrease of magnetic flux density was caused by texture changes with annealing temperature. Increase of annealing temperature makes the coating layer is damaged and oxide layer is formed at interface between coating layer and parent metal. Increase of H 2 gas ratio in annealing atmosphere also affects the magnetic properties weekly by formation of internal oxides.

For Web-based applications in Internet of Things (IoT) environment, the IETF CoRE Working Group developed the Constrained Application Protocol (CoAP). A limitation of CoAP is that it does not address a mobility management for CoAP sensor nodes, which may move between different IP domains of a wireless sensor network. In this paper, we propose the CoAP-based Mobility Management Protocol (CoMP), which can provide mobility management for mobile CoAP sensor nodes. CoMP keeps track of the current IP addresses of mobile sensor and enables sensing data to be reliably delivered to the Web clients, using both HTTP and CoAP. The idea is that CoMP employs a separate location management function to support CoAP service mobility, and two operating modes, CoMP holding and binding modes, are used for a reliable data transmission during handover. To do this, we have designed the architecture of CoMP. Furthermore, we have designed the detailed signaling flow, the message format and algorithm of CoMP for the mobility support. Finally, the numerical analysis and simulation results of the handover latency and packet loss show the benefits of the proposed protocol.

We demonstrate the integration of nanowires to design gate-all-around field-effect-transistors (GAA-FETs) in the shape of horizontally aligned 3-dimensional semiconductor nano-bridges. The transistors exhibited a high on/off-current ratio, low sub-threshold swing and very low off-currents. In addition to designing low-voltage non-volatile memory cells, the photosensitivity of the FETs is employed to demonstrate several analog and digital applications such as electro-optical OR gate circuit elements and frequency doublers. Based on this approach, nanowires with high mobility can be integrated on Si platform to enable the next generation high performance nanowire FETs.

For the first time, herein we demonstrate gate-all-around field-effect-transistors having a horizontally suspended nanowire channel. The suspended nanowires were grown using the vapor-liquid-solid technique. The gate-all-around field-effect-transistor exhibited a p-type accumulation mode with desirable performance. To study properties of the connection between the nanowire channels and electrodes, measurements of surface photocurrent and temperature dependent current-voltage between source and drain electrodes were carried out. The results including an energy band diagram are discussed in this paper.

In order to provide the mobile multimedia service cost-effectively, the smartphone user's demand on free access to widely deployed Wireless LAN (WLAN) systems has been greatly increasing. This is because 3G or 4G mobile networks are usually expensive, and slower than WLAN. Unfortunately, although secure WLANs are installed widely, they are usually not shared. In this article, we have designed and implemented secure WLAN access sharing system using Social Network Service (SNS). A new secure WLAN access sharing model has been designed and implemented, in which the social trust strength between people is employed for secure WLAN access control.

As the performance of the next-generation broadband wireless networks is dramatically enhanced, various real time multimedia services have been provided to users through a smart mobile platform. Most of previous research attempts to provide multimedia streaming service are not suitable to support QoS-guaranteed multimedia streaming service. In addition, they have scalability problem with regard to traffic management. In this article, we have designed architecture of P2P-based group service management for live video streaming communication. More specifically, we have designed the group management protocol and algorithm for group member management and the traffic management. We have mathematically analyzed the performance with regard to the average transmission delay.

In order to receive mobile multimedia service cost-effectively, the smartphone user's demand on free access to widely deployed wireless LAN (WLAN) systems has been greatly increasing. This is because 3G or 4G mobile networks are usually expensive, and slower than WLAN. Unfortunately, although secure WLANs are installed widely, they are usually not shared. In this article, we have designed and implemented secure WLAN sharing system using social network service (SNS). A new secure WLAN sharing model has been proposed in which the social trust strength between people is employed for secure WLAN access control.

Most of the current mobility management protocols such as the mobile IPv4 or mobile IPv6 and its variants standardized by the IETF do not support global seamless handover. This is because they require comprehensive changes in the existing network infrastructure. In this article, we propose a simple mobility management protocol (SMMP) which can support global seamless handover between homogeneous or heterogeneous wireless networks. The underlying principle of the SMMP is that it uses a separate location management function similar to the session initiation protocol (SIP) to support global user and service mobility. In addition, in the SMMP, bidirectional tunnels are dynamically constructed to support seamless Internet protocol (IP) mobility using the IEEE 802.21 media-independent handover (MIH) standards. The detailed architecture and functions of the SMMP have been designed. Finally, the simulation results, using network simulator NS-2, show that the proposed SMMP outperforms the existing MIPv6 and hierarchical mobile IPv6 (HMIPv6) in terms of handover latency, packet loss and pear signal noise ratio (PSNR).

Precise localization of Wi-Fi Access Point (AP) is becoming increasingly important with the rise of diverse location-based services based on smartphone. In this article, we propose a new method for precise Wi-Fi AP localization using GPS information of smartphone. The idea is that the possible area of Wi-Fi AP location, called AP_Area, is first determined by measuring GPS information and the Received Signal Strength (RSS) of smartphones from Wi-Fi AP. As the number of measurement points from users' smartphones increases, the AP_Area can be successively narrowed down to the actual AP location. Simulation results show that the proposed algorithm can detect the Wi-Fi AP localization within 5 m (probability over than 80%).

In this paper, we provide a comprehensive survey of recent energy-efficient medium access control (MAC) protocols for wireless body area networks (WBANs) and presents a comparison of the various approaches pursued. At the outset, we outline the crucial attributes for a good MAC. Several sources that contribute to the energy inefficiency are identified. Then, we investigate few MAC protocols devised for WBAN by emphasizing their salient features. As a conclusion, we put forward a number of open research challenges with regard to prospects of medium access techniques and other issues. Refereed/Peer-reviewed

In this article, we present QoS-Guaranteed local mobility management with bicasting tunnels for mobile devices with dual interfaces. The IETF standard HMIPv6 has been extended where bi-casting tunnels between an access router and the mobile node in 3G/WiFi network are dynamically constructed using dual interfaces. The detailed signaling procedure for the extension of HMIPv6 has been designed and NS2 simulation has been done for performance evaluation. The simulation results show that, comparing with other standard IP mobility management protocols such as MIPv6 and HMIPv6, the proposed mechanism demonstrates better performance in terms of handover latency, packet loss the peak signal noise ratio and jitter delay.

Design of power-efficient medium access control (MAC) protocols in wireless body area networks (WBANs) is important as it helps to prolong the network lifetime. This paper attempts to survey recent works of power efficient MAC protocols for WBANs and presents a comparison of the approaches pursued. We investigate a few MAC protocols devised for WBAN by highlighting their salient features. Finally, a number of open research issues are discussed. Refereed/Peer-reviewed

Recently, there appear diverse smart phones with dual wireless interfaces such as Wi-Fi and 3G. In this article, we present a novel IP mobility management scheme in which dual wireless network interfaces are assigned active IPv6 Care-of-Addresses and used simultaneously for achieving fast handover without packet loss. In order to do that, the IETF standard HMIPv6 has been extended such that while the mobile node is moving, parallel distribution packet tunnels between an access router and the MN are dynamically constructed using dual interfaces. The detailed architecture and algorithms for the extension of HMIPv6 has been designed and simulation has been done for performance evaluation. The simulation results show that the proposed mechanism demonstrates high efficiency with regard to handover latency, packet loss and throughput.

Wireless body area network is one of the most suitable technologies for building patient monitoring systems in hospitals, residential and work environment. The reliability of wireless body area networks is an important research issue since it may jeopardize the vital human life, unless managed properly. In this paper, a new modeling and analysis of in multi-type failures in a wireless body area networks is presented. First, the nodes are classified into types in accordance with their functions. Then, the node behavior has been modeled using a novel Semi-Markov process. Simulation has finally been performed to evaluate the performance of the proposed model.

The IEEE has recently started to develop a standard for the wireless body area network (WBAN). Providing high mobility with guaranteed QoS over the u-healthcare network which are built from the converged WBAN and WLAN systems is a challenging task. This article proposes a context-aware mobility management framework which can support high mobility in the converged WBAN and WLAN networks. The salient feature of the approach is that in order to support seamless mobility management, the context information on the communication environment, the type of service, and the medical emergency has been utilized, while minimizing the power consumption. The service model and algorithms for the context-aware mobility management have been developed in detail. Simulations have finally been performed to show the efficiency of the proposed mechanism.

Providing handover with guaranteed QoS for real-time multimedia service such as VoIP, video/audio streaming, and video conferencing in wireless LAN is a challenging task. In this paper, we present a context-aware mobility management mechanism in wireless LAN, which can provide fast handover with guaranteed QoS for real-time multimedia service. To this end, the scanning period and the number of channels per scanning for handover are dynamically adapted to application context, so that both the degradation of application service quality and energy consumption are minimized simultaneously. The performance of the proposed mechanism is verified by the simulation. The simulation results show that the proposed mechanism is useful for the personalized network which is comprised of wireless LANs.

In this paper, we have designed and implemented the system architecture for extensible mobile instant messaging and presence service over the IMS. More specifically, we have implemented the SIP proxy servers for IMS P-CSCF and S-CSCF for the realization of extensible mobile instant messaging and presence service. The salient feature of the proposed system architecture is that the architecture is based on IETF SIMPLE standard, and the extensibility of the presence service is achieved by implementing theOMA IMPS specification. An efficient algorithm is presented for achieving the extensible presence service over IMS. The implementation results show that the proposed system architecture can effectively provide not only interoperability but also extensibility for representing userspsila status information in the 3 G mobile communication environment.

In the IETFpsilas FMIPv6 protocol, if a prediction about a mobile node movement is incorrect, both large handover latency and packet loss may result. In this letter, we have proposed an intelligent mobile IPv6 handover scheme, called IMIPv6, which can remedy the above limitations of the FMIPv6. In the IMIPv6, multiple pre-registrations of CoAs, intelligent movement detection and late tunneling are employed to reduce handover latency and to eliminate packet loss. The simulation results show that the IMIPv6 can drastically reduce the handover latency, while eliminating packet loss.

In IETFpsilas fast mobile IPv6, the mobile node may switches into the reactive mode of handover operation when the prediction of the movement is wrong. In this case, the mobile node may experience severe service disruption due to large handover latency and packet loss. In order to solve this problem, we propose a fast mobile IP handover with multiple pre-registration. In the proposed approach, the new IP addresses are prepared in advance at multiple locations where the mobile node may probably moves into. If the predictive mode of handover operation by FMIPv6 fails, the mobile node tries to move into the previously prepared locations. Therefore, delay time of generating new care-of-address is saved. We have built a prototype system, and measure the performance of the proposed system. The experimental results show that the proposed approach can reduce greatly the handover latency.

Recent advances in home network technology, combined with IP-based home appliances such as IPTV, can provide high-quality IP-based video conferencing service at relatively low cost. This paper presents SIP-based management architecture for large-scale home conferencing service using IPTV. In the proposed architecture, we extended the protocol stack of IPTV for the support of SIP-based signaling, and applied IPTV to large-scale home conferencing. High scalability of the proposed architecture is achieved by coordinated distributed conference control and media processing. The signaling procedures for the integrated control of IPTV have been designed in detail for SIP-based conferencing service. The performance of the proposed system has been evaluated by simulation. The simulation results show that the proposed architecture greatly improves scalability 1 .

The Real Time Locating Systems (RTLS) based on a set of Location Access Points (LAP) receiving radio frequency (RF) and associated computing equipment are models which determine the position of a transmitting device relative to the placement of the aforementioned receivers that is capable of reporting that position within several minutes of the transmission used for determining the position of the transmission. The RTLS has been widely applied in various areas such as parts replenishment, vehicle management, yard management, container management and assert management. The most challenging issues which render to reach the required accuracy for the time-based location system are non line of sight (NLOS) propagation problems. The NLOS environment prevents a LAP from receiving RF signals from an RTLS tag. Namely, RTLS which tracks location by using time difference of arrival (TDOA) cannot exactly receive RF signals from an RTLS tag attached to the object. Therefore, the estimated location of an RTLS tag is different from a tag location. Accordingly, the Kalman filtering techniques are applied to RTLS to improve the its accuracy. The Kalman filter is rather a recursive estimator than a batch estimator. Because, it gradually converges estimation by using a set of the estimated data one by one. We propose an location filter designed using the Kalman filter for location mitigation in an NLOS environment. We used the linear equation and the observation equation to apply this system to the Kalman filter.

The correlation between gate current and substrate current in surface channel(SC) PMOS with effective channel length down to 0.15 /spl mu/m is investigated within the general framework of the lucky-electron model. It is found that the impact ionization rate increases, but the device degradation is not serious in deep submicrometer PMOS. To extend the lucky-electron model to deep submicrometer regime, we empirically model the effective pinch-off length as a function of the gate length and the gate bias voltage. SCIHE is suggested as the possible physical mechanism for the enhanced impact ionization and the gate current reduction.

As various multimedia communication services are increasingly required by Internet users, several signaling protocols have been proposed for the efficient control of multimedia communication services. However, the model and architecture of multimedia conferencing which is currently being standardized by IETF is not suitable to meet the requirement for the management of large-scale multimedia conferencing service. In this paper, we have presented a management mechanism for distributed architecture of large scale multimedia conferencing service which is based on SIP. The high scalability is achieved by the coordinated distributed conference control and associated media processing without disruption of services. The SIP-based control mechanism for achieving the scalability has been designed in detail. Finally, the performance of the proposed architecture has been evaluated by simulation.

DTMOS SOI transistor was simulated by using Env-Krummenacher-Vittoz (EVK) model, because its equations are valid in all regimes of operation, above or below threshold and saturation. The electrical characteristics of GBSOI MOSFET is compared with DTMOS device. The model predicts that subthreshold swing value close to the 60 mV/decade observed in the measured data. But the reduction of subthreshold swing from 80mV/decade in the GBSOI device to 60mV/decade in the DTMOS is due to the reduction of threshold voltage with increased gate bias. The simulated results are compared with measured data.

BGP/MPLS VPN has recently been receiving much attention from industries and standards bodies. It enables Internet service providers to provide IP-services with QoS guarantees to customers over a shared MPLS backbone. We propose an efficient resilient path management mechanism for BGP/MPLS VPN which can rapidly reconfigure MPLS paths in case of multiple link and/or node failure occurrences. An existence condition for finding a fast backup path which satisfies the resilience constraint is derived for a full mesh BGP/MPLS VPN. An efficient path-finding algorithm with O(n) computational complexity is presented. A simple example is presented to illustrate the operation and effectiveness of the approach.

The paper presents the design and performance of a baseband modem for wireless LAN systems. The modem fully complies with the IEEE 802.11g standard draft 4.0. It is capable of operating in any of available modes such as ERP-DSSS/CCK, ERP-OFDM, Extended Rate PBCC, and CCK-OFDM. It offers different data rates from 1 Mbps to 54 Mbps and handles DBPSK, DQPSK, QPSK, 8-PSK, BPSK, 16-QAM, and 64-QAM modulation schemes. We show the BER performance of the presented modem as the result of simulation under AWGN and multipath channels.

In a telecommunication management network (TMN), the interworking of manager and agent needs to exchange and process management information which is defined as the shared management knowledge (SMK) in the ITU-T Recommendation M.3010. The SMK includes information on the protocol knowledge, management functions, managed object classes and their instances and authorized capabilities. We examine in detail the design issues in developing an SMK system for supporting management systems. We present a design of a CORBA-based SMK system including the procedures of obtaining the SMK information from the management information base (MIB) and of the SMK context negotiations. Finally, our effort on the prototype implementation of an SMK system using ORBeline and OSIMIS is presented.

In this paper, we present a framework for managing ATM customer networks using WWW and CORBA technologies. The WWW technology may provide network management operators with platform independence, location independence, friendly and/or consistent management behavior as well as secure management operations. The main problems in a Web-based network management system may include limited management capabilities of HTTP operations and lack of supporting mechanisms for trap or event notifications. These problems are, in this paper, solved by the integration of Java and CORBA technologies. We extend the current Web technology which is being used for transferring various information on Internet to those which can be used to transfer management requests and replies as well as event notifications. A Web browser is used as a universal user interface for monitoring and controlling the activities of the ATM customer networks. We have developed an integrated customer network management system which can manage SNMP-enabled or CMIP-enabled network devices and provide ATM CNM services. In particular, we applied the CORBA technology to accommodate several management protocols such as SNMP, CMIP and other management protocols. Through the CORBA IDL-to-Java mapping, complex management operations as well as event notifications are supported without modification of the current WWW systems.

This study presents the first experimental data for the impact of CMOS hot-carrier degradation on the performance of folded-cascode op-amps. Two types of folded-cascode op-amps have been designed and fabricated using a 0.8 /spl mu/m double-metal CMOS process. After high voltage stress, the degradation of performance parameters such as open-loop voltage gain, offset voltage, unity-gain frequency and phase margin has been analyzed and physically explained in terms of hot-carrier degradation.

This paper presents a framework for managing customer networks using the Web technology. This framework extends the current Web technology which is being used for transferring various information on the Internet to those which can be used to transfer management requests and replies as well as traps and event notifications. A Web browser is used as a universal user interface for monitoring and controlling the activities of the networks. Using this framework, we have developed an integrated customer network management system which can manage SNMP-enabled or CMIP-enabled network devices. We also applied the CORBA technology to accommodate both SNMP and CMIP protocols. The details of our prototype implementation are also presented.

In this paper, a network architecture for the integration of IRIDIUM and CDMA systems is proposed. In particular we design the architecture of Clearing House. The mechanisms of signaling protocol translation and parameter matching for numbering between IRIDIUM and CDMA systems have been designed and realized in Clearing House. New signaling procedures for location registration and call setup in the integrated network are also proposed.

In this paper, we design and implement a generic transaction capabilities (TC)/common object request broker architecture (CORBA) gateway necessary to provide inter-operability between CORBA-based control systems and legacy control systems using TC-based control protocols, such as an intelligent network application part protocol (INAP) and a mobile application part protocol (MAP). In addition, we introduce an object pool mechanism (OPM) to maintain control application objects in the CORBA domain and evaluate the performance of OPM. As a result, the object access time in a TC/CORBA gateway is reduced.

There have been growing research interests for the realization of a CORBA-based network management system for a telecommunication network, and several methods have been devised to apply CORBA technology to telecommunication management network. We consider a pure CORBA-based network management system. In this system, there is no conventional CMIP agent in a managed system. Otherwise, a managed system contains CORBA-based managed objects with which CORBA-based managing objects interact and perform the management task. To represent the containment relationship between CORBA-based managed objects in a managed system, a naming tree is used. To form the tree, a CORBA naming service is utilized. However, OMG's CORBA naming service requires the entire CORBA-based management objects to be instantiated at all times. Since the network elements usually do not have sufficient system resources, the applications running on them may experience severe degradation in performance. We design a new CORBA naming service. By modifying the OMG's naming service and adding an IDL definition for the new naming service, one can efficiently construct a naming tree without instantiating all the managed objects all at once. CORBA IDL is defined for the new naming service, and performance of the implementation is evaluated to demonstrate its efficiency.

Global number portability (GNP) is becoming a key service to increase competition and profit of a service provider in the ever-growing telephone marketplace. In this paper, we propose an architecture for providing GNP by extending the structure of the legacy local number portability (LNP) scheme of the Number Portability Administration Center Service Management System (NPAC SMS). The architecture is based on CORBA, so that the proposed system can be well integrated with other management systems. We have defined the interfaces using CORBA IDL to enable NPAC SMS to communicate with each other, and designed the procedures for managing routing numbers in multiple LNP domains. A CORBA-based GNP management system can enhance the interoperability required for the integration of different LNP management systems.

This paper presents a multi-domain Internet service management framework that uses service level agreement (SLA) to support QoS and to exchange management information across domain boundaries.