• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.22 no.8
• /
• pp.75-81
• /
• 2008

Water treatment study employing plasma is thoroughly examined in the following paper. The research using water plasma torch showed superior results in terms of economical and energy efficiency due to the substantial reduction of electric power. A comparison of streamer and arc discharge phenomena taken place in water was put under close scrutiny. Dyeing wastewater exposed to the plasma treatment was sampled and analyzed for relative dissolved ozone concentration, hydrogen peroxide, as well as the color removal efficiency. It was found that streamer discharges is more effective than arc discharge in growth of $H_2O_2$ and $O_3$ by plasma chemical constituents, though plasma torch had small oxidation reagents selectivity. Thus, streamer discharges, due to the efficient plasma-chemical reactions environment, proved to be more efficient compare to the thermal arc plasma loading.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2008.08a
• /
• pp.128-132
• /
• 2008

본 논문에서는 현재 자가용 차량 번호판으로 사용되고 있는 4종류의 번호판인, 구형 녹색 번호판 두 종류와 유럽식 신형 흰색 번호판 두 종류에 대해 개별 코드를 효과적으로 추출하기 위한 개선된 퍼지 이진화 방법을 제안한다. 차량 영상에서 수직 에지와 반복 이진화 기법, 그리고 Grassfire 알고리즘을 적용하여 번호판의 후보 영역을 추출하고, 번호판의 형태학적 특징을 이용해 잡음을 제거한 후, 최종 번호판 영역을 추출한다 추출된 번호판 영역에서 개선된 퍼지 이진화 기법을 적용하여 개별 코드를 추출한다. 본 논문에서 제안하는 개선된 퍼지 이진화 방법은 추출한 번호판 영역을 그레이 레벨로 변환한 후에 번호판의 명도를 2구간으로 나누고 각각의 구간에 퍼지 소속 함수를 적용하여 번호판 영역을 이진화한 후, 퍼지 소속 함수에 의해 이진화 된 2개의 번호판 영역 중에서 가장 최적화된 번호판 영역을 선택하여 개별 코드를 추출한다. 본 논문에서 제안한 기법을 4종류의 번호판이 부착된 327장(구형녹색 50장, 신형녹색 157장, 짧은 흰색 60장, 긴 흰색 60장)을 대상으로 실험한 결과, 번호판 영역 추출은 327장의 영상중 97%가 추출되었고 개별 코드 추출은 번호판 영역이 추출된 324장의 영상에서 97%가 추출된 결과를 보였다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.18 no.11
• /
• pp.1726-1734
• /
• 1993

This paper propose a survivable communication network design process using node degree that augments the usual traffic flow and cost analyses with previously ignored topological survivability and computing time considerations. At first, decide a initial topology, and then measure a throughput of network. If the throughput is smaller than the required traffic, add edge to the optimum place by using minimum node degree and link distance. Otherwise, drop useless edge by using maximum node degree, link distance and link utilization. This process is repeated until throughput equals to the required traffics. This Process designs a survivable communication network with the minimized cost and computing time and usual traffic flow. The design proceses that minimized computing time are freely select initial topology and easily design a large network. And these results of algorithm are compared with the Kris and Pramod's in order to analyses the perfmance of the designed network.

• Archives of design research
• /
• v.17 no.3
• /
• pp.441-448
• /
• 2004

Mobile devices such as mobile phones or PDAs are considered as main interlace tools in ubiquitous computing environment. For searching information in mobile device, it should be possible for user to input some text as well as to control cursor for navigation. So, we should find efficient interlace method for text input in limited dimension of mobile devices. This study intends to suggest a new approach to mobile interaction using camera based virtual keyboard for text input in mobile devices. We developed a camera based virtual keyboard prototype using a PC camera and a small size LCD display. User can move the prototype in the air to control the cursor over keyboard layout in screen and input text by pressing a button. The new interaction method in this study is evaluated as competitive compared to mobile phone keypad in left input efficiency. And the new method can be operated by one hand and make it possible to design smaller device by eliminating keyboard part. The new interaction method can be applied to text input method for mobile devices requiring especially small dimension. And this method can be modified to selection and navigation method for wireless internet contents on small screen devices.

• The KIPS Transactions:PartB
• /
• v.13B no.2 s.105
• /
• pp.89-96
• /
• 2006

In this paper, we propose two approaches for the character segmentation on Korean document images. One is an improved version of a projection profile-based algorithm. It involves estimating the number of characters, obtaining the split points and then searching for each character's boundary, and selecting the best segmentation result. The other is developed for low quality document images where adjacent characters are connected. In this case, parts of the projection profile are cut to resolve the connection between the characters. This is called ${\alpha}$-cut. Afterwards, the revised former segmentation procedure is conducted. The two approaches have been tested with 43,572 low-quality Korean word images punted in various font styles. The segmentation accuracies of the former and the latter are 91.81% and 99.57%, respectively. This result shows that the proposed algorithm using a ${\alpha}$-cut is effective for low-quality Korean document images.

• The Transactions of the Korea Information Processing Society
• /
• v.6 no.12
• /
• pp.3718-3726
• /
• 1999

Color image is more effective than gray one in human visual perception. Therefore, color image processing becomes important area. Color images are often corrupted by noises due to the input sensor, channel transmission errors and so on. Some filtering techniques such as vector median, mean filter, and vector $\alpha-trimmed$ mean filter have been used for color noise removal. Among them, vector $\alpha-trimmed$ mean filter gave the best performance in the mixed color noise. But, there are edge shift and blurring effect because vector $\alpha-trimmed$ mean filter is uniformly processed across the image. So, we proposed a conditional fuzzy cluster filter to improve this problems. Simulation results showed that the proposed scheme improves the NCD measure and visual quality over the conventional vector $\alpha-trimmed$ mean filter in the mixed color noise.

• The Korean Journal of Applied Statistics
• /
• v.28 no.1
• /
• pp.9-21
• /
• 2015

The support vector machine has been successfully applied to various classification areas due to its flexibility and a high level of classification accuracy. However, when analyzing imbalanced data with uneven class sizes, the classification accuracy of SVM may drop significantly in predicting minority class because the SVM classifiers are undesirably biased toward the majority class. The weighted $L_2$-norm SVM was developed for the analysis of imbalanced data; however, it cannot identify irrelevant input variables due to the characteristics of the ridge penalty. Therefore, we propose the weighted $L_1$-norm SVM, which uses lasso penalty to select important input variables and weights to differentiate the misclassification of data points between classes. We demonstrate the satisfactory performance of the proposed method through simulation studies and a real data analysis.

• The Korean Journal of Applied Statistics
• /
• v.30 no.1
• /
• pp.135-145
• /
• 2017

Principal component analysis (PCA) describes the variation of multivariate data in terms of a set of uncorrelated variables. Since each principal component is a linear combination of all variables and the loadings are typically non-zero, it is difficult to interpret the derived principal components. Sparse principal component analysis (SPCA) is a specialized technique using the elastic net penalty function to produce sparse loadings in principal component analysis. When data are structured by groups of variables, it is desirable to select variables in a grouped manner. In this paper, we propose a new PCA method to improve variable selection performance when variables are grouped, which not only selects important groups but also removes unimportant variables within identified groups. To incorporate group information into model fitting, we consider a hierarchical lasso penalty instead of the elastic net penalty in SPCA. Real data analyses demonstrate the performance and usefulness of the proposed method.

• Journal of Soil and Groundwater Environment
• /
• v.8 no.1
• /
• pp.1-8
• /
• 2003

Three different surfactants, APG, Brij30, and SDS, were tested to study the characteristics of sorption on soil surfaces, washing ability, biodegradability, and electrokinetic removal. Kaolinite and phenanthrene were selected as a model soil and a representative HOC, respectively. Phenanthrene was sorbed on kaolinite up to 2,200 mg/kg dry soil. The APG, Brij30, and SDS were sorbed on soil to 40, 7, and 4g/kg soil, respectively. The washing ability of phenanthrene was in order of Brij30＆gt;SDS＆gt;APG. The biodegradability tested with sludge was in order of APG＆gt;Brij30＆gt;SDS. In the electrokinetic test, the highest removal efficiency was obtained with APG that exhibited the highest electroosmotic flow. To increase the removal efficiency of HOC in the electrokinetic remediation, the most important factor was the selection of surfactant which maximized the electroosmotic flow.

• Membrane Journal
• /
• v.25 no.5
• /
• pp.431-439
• /
• 2015

The study was evaluated and compared to commercial heterogeneous membrane in order to make cation exchange membrane set up the optimal preparing condition. The research findings show that ion exchange resin was added more than 40 wt% in order to show chemical properties of HPVDF higher than commercial heterogeneous membrane. But ion exchange resin was added less than 40 wt% in order to show mechanical properties of HPVDF higher than commercial heterogeneous membrane. According to conditions above, Electrical resistance was $1.83{\Omega}{\cdot}cm^{-1}$, water uptake was 79%, ion exchange capacity was 1.60 meq/g, and burst strength was 0.97 MPa. Also The TDS remove efficiency was measured by approximately 40%.