Foundation University and The Attached Institute Of Etri | Date: 2014-07-03
Various examples are provided for spherical monopole antennas. In one example, among others, a spherical monopole antenna includes a spherical conductor on a first side of a substrate and a ground plane disposed on the substrate. The spherical conductor is electrically coupled to a connector via a tapered feeding line and the ground plane surrounds at least a portion of the connector on the second side of the substrate. In another example, among others, a method includes forming a tapered mold in a die layer disposed on a first side of a substrate, filling the tapered mold with a conductive paste, and disposing a spherical conductor on a large end of the tapered mold. The conductive paste is in contact with a signal line extending through the substrate into a small end of the tapered mold and in contact with the spherical conductor.
Rhee K.,The Attached Institute of ETRI |
Won D.,Sungkyunkwan University |
Jang S.-W.,The Attached Institute of ETRI |
Chae S.,The Attached Institute of ETRI |
Park S.,The Attached Institute of ETRI
Electronic Commerce Research | Year: 2013
To enhance the security of mobile devices, enterprises are developing and adopting mobile device management systems. However, if a mobile device management system is exploited, mobile devices and the data they contain will be compromised. Therefore, it is important to perform extensive threat modeling to develop realistic and meaningful security requirements and functionalities. In this paper, we analyze some current threat modeling methodologies, propose a new threat modeling methodology and present all possible threats against a mobile device management system by analyzing and identifying threat agents, assets, and adverse actions. This work will be used for developing security requirements such as a protection profile and design a secure system. © 2013 Springer Science+Business Media New York.
Kim K.S.,The Attached Institute of ETRI |
Jeong I.R.,Korea University
Security and Communication Networks | Year: 2015
In 2012, D. Schr öder and H. Schr öder introduced verifiable data streaming (VDS) that enables a client to append, search, verify, and update the streamed data efficiently. After storing the data with a server, a client issues a query to receive a proof that the data of the client are still correctly stored. Anyone can check the validity of the proof publicly in VDS. However, the length of a secret of a client, the length of a proof, and the complexity of appending an element in the previous VDS schemes are O(logn), where n is the upper bound on the number of elements to be stored. In this paper, we suggest a more efficient VDS scheme. In our scheme, the length of a secret of a client is only O(1), and the length of a proof and the complexity of appending an element are O(logi), where i(≤n) is the index of an element. We also show that our scheme is secure under any collision-resistant hash functions and unforgeable signature schemes without random oracles. © 2015 John Wiley & Sons, Ltd.
Lee C.,Dong - A University |
Jung D.,The Attached Institute of ETRI |
Lee K.-W.,Chungwoon University
International Journal of Control and Automation | Year: 2013
Conventional electric-power grids generally have unidirectional power flows from the power plant to the consumers. At small factories, however, the problem is that they inefficiently consume electricity because they consume the electrical power depending on the time of day (e.g., on-peak usually during the day and off-peak usually at night time). In this paper, we try to improve the existing energy management system and propose an energy management system that mainly focuses on the efficiency of electricity consumption. In the proposed management system, PMU (Power Management Unit) installed in switchboard is allowed to collect electric power data in a real time. We also use data mining method, which is applied to analyze the collected data for improving energy efficiency. Also, our proposed energy management system is designed to efficiently control electricity between PMU and management system in case of a shortage of electricity or surplus electricity. Through the experiment, we demonstrate that our proposed system improves the efficiency of electric power of small scale power plant.
Jeon S.,The Attached Institute of ETRI |
Yun J.-H.,The Attached Institute of ETRI |
Kim W.-N.,The Attached Institute of ETRI
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2016
The tendency in cyber attacks has evolved from ones immediately causing abnormal operations to advanced attacks after information extraction by traffic sniffing. In particular, the unchanging characteristics of CIS networks are more susceptible to advanced attacks through information extraction. In this paper, we suggest the concept of an obfuscation method for CIS network traffic to interfere with information extraction. We investigated the characteristics of CIS traffic as found from real data. Based on our observations, we propose a method of creating fake communication to make the best use of surplus network bandwidth. We show that our method can vary the characteristics of a CIS network to prevent information extraction by sniffing. © Springer International Publishing Switzerland 2016.
Cho Y.-J.,The Attached Institute of ETRI
International Journal of Control and Automation | Year: 2013
Because nonlinear systems have more complex behaviors than linear systems, it is hard to apply classical linear system theories and techniques to analyze and control nonlinear systems. So, to apply these theories and techniques, the feedback linearization method is used when the nonlinear system satisfies certain conditions. In the linearizing procedure, there exist infinite pairs of coordinates transformations and feedback controllers. The freedom in the exact linearization technique is used to improve the feedback system in some sense. So, by the switching control with the proper switching rule, we can obtain the better transient behavior than that of using one diffeomorphism. For many real processes, nonlinear systems have uncertainties. Because the linearizing method requires the accurate mathematical models of the system for the exact linearization, the uncertainties have an effect on stability of the nonlinear system. But, if we know the bounds of uncertainties, we can compensate the uncertainties based on the Lyapunov redesign technique. In this paper, we propose a switching rule for taking the transient behavior improvements in the case of uncertain time-varying nonlinear system.
Kwon D.-K.,The Attached Institute of ETRI |
Chung K.H.,Ajou University |
Choi K.,Ajou University
Journal of Information Processing Systems | Year: 2013
One of the obstacles preventing the Zigbee protocol from being widely used is the excessive power consumption of Zigbee devices in low bandwidth and low power requirement applications. This paper proposes a protocol that resolves the power efficiency problem. The proposed protocol reduces the power consumption of Zigbee devices in beacon-enabled networks without increasing the time taken by Zigbee peripherals to communicate with their coordinator. The proposed protocol utilizes a beacon control mechanism called a "sleep pattern," which is updated based on the previous event statistics. It determines exactly when Zigbee peripherals wake up or sleep. A simulation of the proposed protocol using realistic parameters and an experiment using commercial products yielded similar results, demonstrating that the protocol may be a solution to reduce the power consumption of Zigbee devices© 2013 KIPS.
Choi Y.H.,The Attached Institute of ETRI |
Kim T.G.,The Attached Institute of ETRI |
Choi S.J.,The Attached Institute of ETRI
International Journal of Security and its Applications | Year: 2010
Rhee K.,The Attached Institute of ETRI |
Kim H.,The Attached Institute of ETRI |
Na H.Y.,The Attached Institute of ETRI
International Journal of Security and its Applications | Year: 2012
In this paper, we propose test items and methods for security functions of Mobile Device Management agent. Recently, many enterprises are adopting Mobile Device Management system to manage smart phones and tablet PCs used in business. However, there is no criteria to test whether such Mobile Device Management system correctly provide required security functions and whether such functions are secure. Especially, no criteria have been established as yet to test an agent which is installed on the mobile devices and directly controls the mobile devices. Therefore, we propose the first test methodology to test the Mobile Device Management agent by identifying security requirements and drawing test items and methods. The proposed items and methods are practical since we illustrate the test items, their processes, and real world test methods for Android devices.
Jung D.,The Attached institute of ETRI |
Lee C.,Soongsil University
International Journal of Multimedia and Ubiquitous Engineering | Year: 2014
Recently, due to the interest for personal safety, intelligent image recognition technology using the CCTV has received a lot of attention in many areas. Real-time video or image tracking technology is the technology to continuously track the movement of the target object and maintain the specified information of the object. However, the problem is that unnecessary noise or environmental changes of the input video from CCTV make it difficult to accurately detect and track the target object. In this paper, we propose a fast object tracking algorithm, which is divided into two parts: i) object detection process and ii) object tracking process. In the background image replacement technique, we compute the difference between the initial input image and input video image. Then, it replaces N×M blocks based on the changed pixels, finally leading to replacing the background images. If it changes over the pre-defined threshold value, we set the block size and generate the variable search window for object tracking. Since the variable search window only generates the minimum search area for object tracking, our proposed method is quickly able to compute the variable region for object tracking. Through various experiments, our proposed scheme outperforms the other object detection and tracking methods in terms of object tracking counts and tracking error counts. © 2014 SERSC.