• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.3 no.1 s.4
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• pp.75-83
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• 2004

This paper describes the design, fabrication, and measurement of a low side lobe antenna for RSE base station of the ETCS which is one of the ITS services. The antenna is installed on the gantry of road side and provides the wireless communication lint between vehicles and RSE. The required characteristics of ETCS base station antenna are low sidelobe and specific beam pattern by the road and install environment and installed place of OBU. To minimize the affects of multipath signal by reflection, Circular polarization is required. To get low sidelobe of antenna, array configuration and weighting factor by Taylor distribution in radiator elements are applied. The measured results of fabricated antenna are as follows; return loss of 130MHz by -10dB, an axial ratio of 2.6dB, and a gain of 17dBi. It is found that the measured beam patterns are similar to design results.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.3 no.2 s.5
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• pp.95-104
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• 2004

This paper describes the design, fabrication, and measurement of a omni-directional beam pattern antenna for base station of the BIS which is one of the ITS services. The antenna is installed on the signal lamp of important crossroad and provides the wireless communication link between vehicles and RSE(Road Side Equipment). The required characteristics of BIS base station antenna are omni-directional beam pattern and specific beam pattern by the road and install environment and installed place of OBU. To get omni-directional beam pattern of antenna, Array configuration and OMA are applied. The measured results of fabricated antenna are as follows; return loss of 640MHz by -10 dB, and a gain of 10.3dBi. It is found that the measured beam patterns are similar to design results.

• Journal of the Korea Convergence Society
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• v.7 no.6
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• pp.43-48
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• 2016

Wireless sensor networks (WSN) can be more reliable and easier to program and use with the help of sensor database management systems (SDMS). SDMS establish a user-friendly SQL-based interface to process declarative user-defined queries over sensor readings from WSN. Typical queries in SDMS are ad-hoc snapshot queries and long-running, continuous queries. In SDMSs queries are flooded to all nodes in the sensor net, and query results are sent back from nodes that have qualified results to a base station. For query flooding to all nodes, and result flooding to the base station, a lot of communication energy consuming is required. This paper suggests an efficient in-network index solution, named Distributed Information Gathering (DIG) to process range queries in a sensor net environment that can save energy by reducing query and result flooding.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.28 no.3
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• pp.665-679
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• 2018

With the development of information and communication technology, especially wireless Internet technology and the spread of smart phones, digital data has increased. As a result, privacy issues which concerns about exposure of personal sensitive information are increasing. In this paper, we analyze the privacy vulnerability of online big data in domestic internet environment, especially focusing on portal service, and propose a measure to evaluate the possibility of privacy violation. For this purpose, we collected about 50 million user posts from the potal service contents and extracted the personal information. we find that potal service user can be identified by the extracted personal information even though the user id is partially anonymized. In addition, we proposed a risk measurement evaluation method that reflects the possibility of personal information linkage between service using partial anonymized ID and personal information exposure level.

• Journal of Korea Society of Digital Industry and Information Management
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• v.10 no.2
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• pp.61-73
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• 2014

An automatic vehicle location tracing system is to build GIS server and on transmission for providing service in various ways by collecting a GPS location information from each vehicle. It is to save GPS data from OBU built-in on the vehicle and transmit the GPS data using the RSU on the roadside and WAVE communication technology. The collected data from the RSU is transmitted to the GIS server and stored in DB(database) and based on the GPS data that was collected from the each vehicle the system is to provide user service to suit the applications so it is to provide various services between RSU and OBU. In this paper, by implementing a multi-session process between the RM and the RMA a variety of services between RSU and OBU are provided. In addition, the system is designed and implemented using GPS to provide a variety of services, for the services provided from each RMA by configuring them as an independent session so it enables a variety of services implemented from one of RSU. With the result of the comparative analysis on the multi-session processing and single-session processing it shows that the differenes of them are minor in repect of the data loss rate and the data transfer rate but various services can be provided.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.12
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• pp.5049-5057
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• 2010

As communication technologies are developed and variety of services to mobile devices are provided, mobile users is rapidly increasing every year. However, mobile services running on wireless network environment are exposed to various security threats, such as illegal tampering, eavesdropping, and disguising identity. Accordingly, the secure mobile communications services to 3GPP were established that the standard for 3GPP-AKA specified authentication and key agreement. But in the standard, sequence number synchronization problem using false base station attack and privacy problem were discovered through related researches. In this paper, we propose an efficient authentication mechanism for enhanced privacy protection in the 3G network. We solve the sequence number synchronization existing 3GPP authentication scheme using timestamp and strengthen a privacy problem using secret token. In addition, the proposed scheme can improve the bandwidth consumption between serving network and home network and the problem of authentication data overhead for the serving network because it uses only one authentication vector.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.7
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• pp.566-569
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• 2018

A power line coupler that can apply high-frequency power to a railway overhead line structure was analyzed. It is difficult to supply auxiliary power to an overhead line in a high-voltage environment, and doing so requires a long-distance transfer. A method is proposed that utilizes the resonance on the Rogowski coil, which does not use a magnetic core. A simple overhead line structure was fabricated that consisted of a contact wire, messenger wire, and dropper. Couplers of various sizes were fabricated and deployed on the messenger wire, and the transfer characteristics of the two couplers were compared at a distance. As a result of applying the matching circuit to the coupler, the transmission efficiency was 53% at a distance of 2.5 m. The proposed method shows that it is possible to apply the auxiliary power by using the existing conductor in a special structure, such as the overhead line.

• Journal of Korea Multimedia Society
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• v.12 no.5
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• pp.708-716
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• 2009

Applications which are implemented on Table Top Display are controlled by hands, so that they support an intuitive interface to users. Users feel the real sense when they interact on the virtual scene in Table Top Display. However, most of conventional augmented reality applications on Table Top Display satisfy only visual sense. In this paper, we propose an interface that supports multi-modal sense in that tactile sense is utilized for augment reality by vibrating a physical control unit when it collides to virtual objects. Users can feel the collision in addition to visual scene. The proposed system facilitates tactile augmented reality through an air hockey game. A physical control unit vibrates when it receives virtual collision data over wireless communication. Since the use of tabletop display environment is extended with a tactile sense based physical unit other than hand, it provides a more intuitive interface.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.05a
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• pp.560-563
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• 2003

In this paper describes for use Authentication with the WPKI and Kerberos protocol. this paper is the security structure that defined in a WAP forum and security and watches all kinds of password related technology related to the existing authentication system. It looks up weakness point on security with a problem on the design that uses wireless public key-based structure and transmission hierarchical security back of a WAP forum, and a server-client holds for user authentication of an application level all and all, and it provides one counterproposal. Therefore, We offer authentication way solution that connected X.509 with using WIM for complement an authentication protocol Kerberos and its disadvantages.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.10B
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• pp.894-903
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• 2008

The position of sensors generally affects coverage, communication costs, and resource management of surveillance sensor networks. Thus we are required to place a sensor in the best location. However, it is difficult to consider that terrain and climate factors influencing sensors when sensor nodes are deployed in the real world, such as a mountain area or a downtown area. We therefore require a sensor deployment method for detecting effectively targets of interest in terms of surveillance area coverage in such environment. Thus in this paper, we analyze various environmental factors related to sensor deployment, and quantify these factors to use when we deploy sensors. By considering these quantified factors, we propose a practical and effective method for deploying sensors in terms of sensing coverage. We also demonstrate the propriety of the proposed method through implementing a sensor deployment management system according to the method.