• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.13 no.6
• /
• pp.1091-1098
• /
• 2009

In this paper, we designed the authentication system for home network service and applied it to actual sensor nodes. The pair-wise pre-distribution key skim is applied for prevention of authentication key from sniffing on the wireless sensor networks. The authentication key and data are encrypted by using the CBC mode RC5 algorithm based on the SPINS. The experimental environment consists of a base station (BS)and sensor nodes and each sensor node sends both sensing data and the encrypted authentication key to the BS. For simulations we set up some what-if scenarios of security menaces in home network service.Slightly modified the TOS_Msg data arrays of TinyOS is suggested to store 8-byte authentication key which can enable data encryption and authentication at the each sensor node. As a result, malfunction caused by communication between BS and nodes of other groups of added nodes having malicious purpose can be protected. Also, we confirmed that a critical data of home networking service like vital signal can be transmitted securely through this system by encryption technique.

• The KIPS Transactions:PartC
• /
• v.12C no.6 s.102
• /
• pp.865-874
• /
• 2005

The information stored in the computer system needs to be protected from unauthorized access, malicious destruction or alteration and accidental inconsistency. In this paper, we propose an intrusion detection system based on sensor concept for defecting and preventing malicious attacks We use software sensor objects which consist of sensor file for each important directory and sensor data for each secret file. Every sensor object is a sort of trap against the attack and it's touch tan be considered as an intrusion. The proposed system is a new challenge of setting up traps against most interception threats that try to copy or read illicitly programs or data. We have implemented the proposed system on the Linux operating system using loadable kernel module technique. The proposed system combines host~based detection approach and network-based one to achieve reasonably complete coverage, which makes it possible to detect unknown interception threats.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.29 no.2A
• /
• pp.147-156
• /
• 2004

This paper presents an implementation and performance analysis of an access channel decoder which exploits a diversity gain due to the independent magnitude of received signals energy at each of antenna elements of a smart antenna BTS (Base-station Transceiver Subsystem) operating in CDMA2000 1X signal environment. Proposed access channel decoder consists of a searcher supporting 4 fingers, Walsh demodulator, and demodulator controller. They have been implemented with 5 of 1 million-gate FPGA's (Field Programmable Gate Array) Altera's APEX EP20K1000EBC652 and TMS320C6203 DSP (digital signal processing). The objective of the proposed access channel decoders is to enhance the data retrieval at co]1-site during the access period, for which the optimal weight vector of the smart antenna BTS is not available. Through experimental tests, we confirmed that the proposed access channel decoder exploitng the diversity technique outperforms the conventional one, which is based on a single antenna channel, in terms of detection probability of access probe, access channel failure probability, and $E_{b/}$ $N_{o}$ in Walsh demodulator.r.r.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.27 no.4
• /
• pp.108-121
• /
• 1999

Creative spatial production in Environmental design relies, in large part, on the artistic talent of the designer(s) that is applied to the design solutions or schematic plans. This study proposes the importance and necessity of the use of 'Plastic Arts" or the technique of artistic manipulation and definition of space in Environmental Design studio programs. This fundamental design approach is currently lacking in Korean design studio programs. Moreover, the current trend of interdisciplinary design (that is, between landscape architecture, architecture, urban and environmental planning) emphasizes the importance of such techniques. "plastic Arts" techniques can serve as a basic code of communication between design disciplines and can in itself be a common approach. The method of this study is based on the empirical datas, that is, the educational performances which are executed in Landscape studio programs of some Korean Universities. The results are summarized as follows; 1. The program, "Plastic Arts" Should be included in the basic organization of Landscape design studio programs. 2. Unlike France where "Plastic Arts" program is implemented through out Landscape Architecture programs in Korea, "Plastic Arts" should be intensified and continued for longer period of time for students in the initial years. 3. In creation of "Plastic Arts" programs for Korean Landscape Design studios, the traditional and contemporary values of aesthetic of the Nature should be taken in consideration. 4. In order to confirm the necessity of "Plastic arts" program in the organization of landscape curriculum, more studies should be done, with empirical datas.pe curriculum, more studies should be done, with empirical datas.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2007.10a
• /
• pp.925-928
• /
• 2007

Abilities of sensing and communication are vested in private things of actual space, therefore, Ubiquitous Computing which is offered various services with human approach will be common in the future society. For the realization of this Ubiquitous Service requires some technique such as situations of environment and recognition of locations by the Sensor Network, then sensor data have to be transferred to an application service after processes. However, there are some hindrances for communication between an application service and sensor data, these are that accessibility of data usefulness and problems of Platform and protocol in each sensors. In this paper, suggest a reference model that is independent from platform and implementation language, for USN application service with using standardized protocol.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.17 no.7
• /
• pp.1538-1543
• /
• 2013

In this paper, a novel split ring resonator is proposed for improvement of phase noise characteristics that is weak point of oscillator using planar type microstrip line resonator. Oscillator using proposed split ring resonator is designed, it has improved phase noise characteristics. At the fundamental frequency of 5.8GHz, 7.22dBm output power and -83.5 dBc@100kHz phase noise have been measured for oscillator with split ring resonator. The phase noise characteristics of oscillator is improved about 9.7dB compared to one using the general ${\lambda}/4$ microstrip resonator. Next, we designed voltage controlled oscillator using proposed split ring resonator with varactor diode. The VCO has 125MHz tuning range from 5.833GHz to 5.845GHz, and phase noise characteristic is -118~-115.5 dBc/Hz@100KHz. Due to its simple fabrication process and planar type, it is expected that the technique in this paper can be widely used for low phase noise oscillators for both MIC and MMIC applications.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.2
• /
• pp.719-723
• /
• 2016

Owing to the recent increased interest in wireless communication technology and rapid technology development, a range of applied technologies utilizing them are being released. In addition, at school, by adopting an attendance management system using wireless communication technology, attempts to solve problems caused by attendance books are being made. Representative attendance management systems include those using RFID, Bluetooth and clicker. Although these systems have solved the problem of wasting paper and time due to calling and writing attendance, they have other problems of generating additional expenses of purchasing or renting more equipment. To solve all of these problems, this paper suggests prototype system that can manage attendance by using NFC (Near Field Communication), which most smartphones provide. The attendance management system using NFC consists of two applications; one for professors and the other for students. The system solves problems, such as proxy attendance, loss of lesson time and additional cost by automatically managing attendance information using NFC and TCP/IP technologies.

• The KIPS Transactions:PartB
• /
• v.13B no.3 s.106
• /
• pp.245-254
• /
• 2006

In this work, a new rate control algorithm for transmission of H.264/AVC video bit stream through CBR(constant bit rate) channel is proposed. The proposed algorithm predicts target bit rate and MAD(mean of absolute difference) for current frame considering image complexity variance between neighboring backward and current images. In details, respective linear regression analysis for MAD and encoded bit rate against image complexity variance produce correlation parameters. Additionally, it uses frame skip technique to maintain bit stream within a manageable range and protect buffer from overflow or underflow. Implementation and experimental results show that the proposed algorithm can provide accurate bit allocation, and can effectively visual degradation after scene changes. Also our proposed algorithm encodes the video sequences with less frame skipping compared to the existing rate control for H.264/AVC.

• The KIPS Transactions:PartA
• /
• v.8A no.2
• /
• pp.107-116
• /
• 2001

A multithreaded model is a hybrid one which combines locality of execution of the von Neumann model with asynchronous data availability and implicit parallelism of the dataflow model. Much researches that have been made toward the advanced performance of multithreaded models are about the cache memory which have been proved to be efficient in the von Neumann model. To use an instruction cache or operand cache, the multithreaded models must have cache memories. If cache memories are added to the multithreaded model, they may have the disadvantage of high implementation cost in the mode. To solve these problems, we did not add cache memory but applied the method of executing the caching by using available registers of the multithreaded models. The available register-based caching method is one that use the registers which are not used on the execution of threads. It may accomplish the same effect as the cache memory. The multithreaded models can compute the number of available registers to be used during the process of the register optimization, and therefore this method can be easily applied on the models. By applying this method, we can also remove the access conflict and the bottleneck of frame memories. When we applied the proposed available register-based caching method, we found that there was an improved performance of the multithreaded model. Also, when the available-register-based caching method is compared with the cache based caching method, we found that there was the almost same execution overhead.

• KIPS Transactions on Computer and Communication Systems
• /
• v.3 no.7
• /
• pp.209-218
• /
• 2014

An AP that is used by smart device is going to be complicated because smart devices support diverse functions. As a result, multiple low-level IPs including a dedicated CPU are integrated in a high-level subsystem for supporting complicated function such as multimedia codec and camera. A subsystem has software that executes separately from main system, and the software needs to be initialized for every execution of the subsystem. This causes increase of the subsystem startup time so it should be improved because startup time of subsystem affects launching time of application. Methods in applied to computer system for fast startup also could be applied to fast startup of subsystem because subsystem is similar with computer system. In this paper, we apply snapshot method that is used in computer system to subsystem and analyzes the pros and cons. And snapshot method could not be applied to register of IP without modification because register of IP offers restricted read and write. So this paper suggests technique that applying snapshot to each characteristic of register.