• Journal of the Korea Institute of Military Science and Technology
• /
• v.14 no.6
• /
• pp.1091-1096
• /
• 2011

The main factors of radar signals used in electronic warfare are Radio Frequency(RF), Pulse Repetition Interval(PRI), Pulse Width(PW), Scan Parameter(SP) and so on. This radar signals may have some important information for the electronic warfare. So, there is a necessity for making a threat database to decide whether the radar signal is a threat or not. When the electronic support system collects some threat radar signals, it needs the search band to control the receivers and filter banks of the system. In this paper we propose search band implementation considering the type and center frequency of the receivers of the electronic support system.

• Journal of Institute of Control, Robotics and Systems
• /
• v.15 no.4
• /
• pp.379-384
• /
• 2009

A human gaze detection and tracing method is importantly required for HMI(Human-Machine-Interface) like a Human-Serving robot. This paper proposed a novel three-dimension (3D) human gaze estimation method by using a face recognition, an orientation estimation and SVMs (Support Vector Machines). 2,400 images with the pan orientation range of $-90^{\circ}{\sim}90^{\circ}$ and tilt range of $-40^{\circ}{\sim}70^{\circ}$ with intervals unit of $10^{\circ}$ were used. A stereo camera was used to obtain the global coordinate of the center point between eyes and Gabor filter banks of horizontal and vertical orientation with 4 scales were used to extract the facial features. The experiment result shows that the error rate of proposed method is much improved than Liddell's.

• Journal of Information Processing Systems
• /
• v.6 no.4
• /
• pp.563-574
• /
• 2010

The growing number of web applications in the global economy has made it critically important to develop secure and reliable software to support the economy's increasing dependence on web-based systems. We propose an intercepting filter approach to mitigate the risk of injection flaw exploitation- one of the most dangerous methods of attacking web applications. The proposed approach can be implemented in Java or .NET environments following the intercepting filter design pattern. This paper provides examples to illustrate the proposed approach.

• The Journal of the Acoustical Society of Korea
• /
• v.30 no.2
• /
• pp.100-106
• /
• 2011

Music recordings have been digitalized such that huge size of music database is available to the public. Thus, the automatic classification system of music genres is required to effectively manage the growing music database. Mel-Frequency Cepstral Coefficient (MFCC) is a popular feature vector for genre classification. In this paper, the combined super-vector with Decorrelated Filter Bank (DFB) and Octave-based Spectral Contrast (OSC) using texture windows is processed by Support Vector Machine (SVM) for genre classification. Even with the lower order of the feature vector, the proposed super-vector produces 4.2 % improved classification accuracy compared with the conventional Marsyas system.

• Journal of Powder Materials
• /
• v.21 no.1
• /
• pp.21-27
• /
• 2014

In this study, diatomite based materials were investigated as a support filter for silica particle coating. The silica sol for coating was synthesized by a st$\ddot{o}$ber process. The diatomite support was dry-pressed at 10 MPa and sintered at $1200^{\circ}C$ for 1 hour. The coating sol was prepared as a mixture of EtOH and silica sol. The diatomite support was coated by a dip-coating process. Silica coated diatomite filter was sintered at $1000{\sim}1200^{\circ}C$ for 1 hour. The largest pore size was decreased with increasing concentration ratio of coating sol. The gas and water permeability of silica coated diatomite decreased with increasing of concentration ratio of the coating sol.

• Journal of the Korean Ceramic Society
• /
• v.46 no.5
• /
• pp.534-539
• /
• 2009

Reaction Bonded Silicon Carbide(RBSC) has been used for engineering ceramics due to low-temperature fabrication and near-net shape products with excellent structural properties such as thermal shock resistance, corrosion resistance and mechanical strength. Recently, attempts have been made to develop hot gas filter with gradient pore structure by RBSC to overcome weakness of commercial clay-bonded SiC filter such as low fracture toughness and low reliability. In this study a fabrication process of porous RBSC with multi-layer pore structure with gradient pore size was developed. The support layer of the RBSC with multi-layer pore structure was fabricated by conventional Si infiltration process. The intermediate and filter layers consisted of phenolic resin and fine SiC powder were prepared by dip-coating of the support RBSC in slurry of SiC and phenol resin. The temperature of $1550^{\circ}C$ to make Si left in RBSC support layer infiltrate into dip-coated layer to produce SiC by reacting with pyro-carbon from phenol resin.

• The KIPS Transactions:PartB
• /
• v.17B no.3
• /
• pp.249-254
• /
• 2010

We propose an automatic spam filter for e-mail data using Support Vector Machines(SVM). We use a lexical form of a word and its part of speech(POS) tags as features and select features by chi square statistics. We represent each feature by TF(text frequency), TF-IDF, and binary weight for experiments. After training SVM with the selected features, SVM classifies each e-mail as spam or not. In experiment, the selected features improve the performance of our system and we acquired overall 98.9% of accuracy with TREC05-p1 spam corpus.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.26 no.1
• /
• pp.33-39
• /
• 2020

The objective of this study was to evaluate the possibility for the coffee filter paper of Hanji. In this study, the samples for Hanji filter papers were prepared with three different mulberry fiber contents of 10, 30 and 50%(w/w). Surface brightness and apparent density of hand-made Hanji decreased with increasing mulberry fiber contents. However, values of thickness, tensile strength, wet tensile strength, burst strength, and folding endurance for hand-made Hanji increased by increasing the contents of mulberry fibers due to fiber-to-fiber bonding. The results of the coffee extraction test using the developed filter papers showed no significant differences between commercial filter paper and Hanji filter paper. Therefore, Hanji filter paper containing more than 30%(w/w) mulberry fiber may have potential uses for the dripped coffee filter application from a physical property point of view.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2009.05a
• /
• pp.592-595
• /
• 2009

We propose an automatic spam mail classifier for e-mail data using Support Vector Machines (SVM). We use a lexical form of a word and its part of speech (POS) tags as features. We select useful features with ${\chi}^2$ statistics and represent each feature using text frequency (TF) and inversed document frequency (IDF) values for each feature. After training SVM with the features, SVM classifies each email as spam mail or not. In experiment, we acquired 82.7% of accuracy with e-mail data collected from a web mail system.

• Journal of Power Electronics
• /
• v.7 no.3
• /
• pp.257-264
• /
• 2007

Active power filters can be cost-effective for use in practical systems with the insertion of a few passive elements in shunt or series configuration. The resulting hybrid filters can be designed to provide dominant lower order harmonic elimination and reactive power support by the passive elements so that the burden on the active filter counterpart is reduced. In this paper, the rate reduction in the shunt active filter is estimated when it is connected in parallel with suitable passive tuned harmonic filters. The active filtering system is based on an appropriate control scheme. The simulation and the experimental results of the shunt active filter, along with the estimated value of reduction in rating, show that the hybrid shunt filtering system is quite effective in compensating for the harmonics and reactive power, in addition to being cost-effective.