• International Journal of Contents
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• 제10권1호
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• pp.23-28
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• 2014

When developing a classifier using various objective functions, it is important to compare the performances of the classifiers. Although there are statistical analyses of objective functions for classifiers, simulation results can provide us with direct comparison results and in this case, a comparison criterion is considerably critical. A Receiver Operating Characteristics (ROC) graph is a simulation technique for comparing classifiers and selecting a better one based on a performance. In this paper, we adopt the ROC graph to compare classifiers trained by mean-squared error, cross-entropy error, classification figure of merit, and the n-th order extension of cross-entropy error functions. After the training of feed-forward neural networks using the CEDAR database, the ROC graphs are plotted to help us identify which objective function is better.

• 산업기술연구
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• 제16권
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• pp.123-129
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• 1996

A method of calculating the natural frequency corresponding to the first mode of vibration of beams and tower structures with irregular cross-sections and with arbitrary boundary conditions was developed and reported by D. H. Kim in 1974. In order to obtain the natural frequency by the presented method, the first step to take is to obtain the deflection influence surfaces. In design and analysis of any structure, the first step to be taken is to obtain this deflection influence surfaces. Any method can be used for this purpose. Then using this surfaces, deflections, slopes, moments, shears, and natural frequencies can be obtained by differentiating either the continuous function or discrete function defined at certain points. The merit of the presented method is that the natural frequency can be obtained by the deflection influence surfaces obtaining which is the first step in structural analysis.

• Clinics in Shoulder and Elbow
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• 제5권1호
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• pp.23-28
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• 2002

Purpose Displaced lateral end fracture of clavicle and acromioclavicular dislocation type Ⅲ∼Ⅵ may be required surgical treatment. Material and Methods : From May 1998 to March 2001, we operated with Welter plate with minimal incision by one surgeon. Immediately, pendulum and passive exercise was initiated after surgery. The shoulder function was evaluated using UCLA score. Average follow up was on 28(12∼45) months. Results : All 11 patients were regained satisfactory function. Average UCLA score was 31.9(29~35) at last follow up. Conclusion . The merit of Welter plate fixation with minimal incision is simple technique, reduced surgical time, smaller scar than large plate, strong fixation, early exercise, reduced implant failure. The disadvantage is expensive, skin irritatatation by long hook. But Welter plate fixation with minimal incision is a good method of internal fixation and excellent clinical result in surgical treatment of type H displaced lateral end fracture of the clavicle and type Ⅲ∼Ⅵ acromioclavicular dislocation.

• International Journal of Contents
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• 제8권4호
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• pp.30-35
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• 2012

Error surfaces provide us with very important information for training of feed-forward neural networks (FNNs). In this paper, we draw the contour plots of various error or objective functions for training of FNNs. Firstly, when applying FNNs to classifications, the weakness of mean-squared error is explained with the viewpoint of error contour plot. And the classification figure of merit, mean log-square error, cross-entropy error, and n-th order extension of cross-entropy error objective functions are considered for the contour plots. Also, the recently proposed target node method is explained with the viewpoint of contour plot. Based on the contour plots, we can explain characteristics of various error or objective functions when training of FNNs proceeds.

• 한국통신학회논문지
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• 제32권5C호
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• pp.530-535
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• 2007

변이공간영상(Disparity space image, DSI) 방법은 스테레오 영상간의 정합을 찾는 방법이다. 이 방법은 각 화소 단위로 변이값을 계산해 내는 장점이 있다. DSI 방법은 비용함수를 최소화시키는 정합을 찾는 방법이다. 이 비용함수에서 폐색영역비용 값과 정합 보상값을 경험적으로 정하여왔다. 본 논문에서는 변이공간영상 방법에서 폐색영역비용과 정합보상값이 영상 잡음과 물체와 배경간의 차이에 영향을 받는 것을 이론적으로 분석하였다.

• 복식
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• 제57권3호
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• pp.23-36
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• 2007

It is important that ubiquitous technology changes paradigm of thought, not simple definition in the 21st digital era. Characteristics of ubiquitous computing are pervasive, disappearing, invisible, calm through environment. As IT Technology develops, designers, computer scientists, chemists, performance artists cooperate in order to find out the best way to make desirable digital clothing in the future, with the merit of each part. Digital clothing defines clothes of new generation equipped computer, digital installations. Digital clothing design demands intercept of electromagnetic waves, light-weight and esthetic appearance, for it is attached high-technology equipment near body. The purpose of this study is to analyze design features of digital clothing according to ubiquitous characteristics. The methods of this study are documentary research of previous study and case study. In the theoretical study, ubiquitous characteristics are function-intensive by convergence, interactivity, embedded mobility and human & emotion-oriented attributes. Based on ubiquitous characteristics, digital clothing design classified function-intensive design by convergence, design for Interactivity and multi-sensible & emotion-oriented design, because embedded mobility is a basic element of ubiquitous environment. The early days digital clothing design is function-intensive design, and have esthetic appearances and design for interactivity increasingly. Recently digital clothing design is expressed multi-sensible and emotion-oriented design.

• 한국자기학회지
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• 제10권3호
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• pp.99-105
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• 2000

두 종류의 유전체 층(A: $SiO_2$, B: T $a_2$ $O_{5}$ )을 주기적으로 적층한 구조에, Bi를 다량 치환한 가네트 박막(M: $Y_{1.93}$ B $i_{1.07}$F $e_{5}$ $O_{12}$ )을 결함층으로 삽입한 (A/B)$^{k}$ /M(B/A)$^{k}$ 의 구조를 갖는 1차원 자성 포토닉 결정의 자기 광학 특성을 수치해석하였다. 가시광과 적외선 영역에서 1차원 자성 포토닉 결정의 자성체 층의 두께( $d_{M}$)와 유전체 층의 적층수(k)를 변화시키며, 투과율(T)과 페러데이 회전각($\theta$$_{F}$ ) 및 성능지수(Q)를 조사하였다. 조사한 1차원 자성 포토닉 결정의 각 국재 모드에서의 페러데이 회전각 및 성능지수의 극대값들은 동일 조성의 단층 가네트 박막에 비해 수 배 내지 수 백 배 큰 값이 얻어졌다. 가시광 영역에서는 k = 11이고, $d_{M}$ = 375 nm일때, 최대값 Q = 0.15이 얻어졌다. 이 값은 단층의 가네트 막에 비해 약 30배 큰 값이며, 이 때의 = 720 nm, T = 0.54, $\theta$ = 8.13$^{\circ}$이었다. 적외선 영역에서는 k = 11이고, $d_{M}$ = 800 nm일때 , 최대값 Q = 0.285(단층 가네트 막에 비해 100배 큰 값)이 얻어졌고, 이 때의 = 1114 nm, T = 0.485, $\theta$$_{F}$ = 18$^{\circ}$이었다.

• 한국정밀공학회지
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• 제19권6호
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• pp.77-85
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• 2002

An analysis method which calculates corrective machining information for improving the motion accuracy of linear motion guide Is proposed in this paper. The method is composed of two algorithms. One is the algorithm fur prediction of the motion errors from rail form error. The other is the algorithm for prediction of rail form error from the motion errors of table. Transfer function is utilized in each algorithm, which represents the ratio of bearing reaction force variation to unit magnitude of spatial frequencies of raid from error. As the corrective machining information is acquired from the measured motion errors of table, the method has a merit not to measure rail form error directly. Validity of the method is verified both theoretically and experimentally. By applying the method, linear motion error of test equipment is reduced from 5.97$\mu$m to 0.58$\mu$m, and reduced from 32.78arcsec to 6.21 arcsec in case of angular motion error. From the results, it is confirmed that the method is very effective to improve the motion accuracy of linear motion guide.

• Transactions on Electrical and Electronic Materials
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• 제14권5호
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• pp.242-245
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• 2013

Sn-doped $In_2O_3$ (ITO) thin films were prepared by radio frequency magnetron sputtering without intentional substrate heating on bare glass and $TiO_2$-deposited glass substrates to investigate the effect of a $TiO_2$ buffer layer on the electrical and optical properties of ITO films. The thicknesses of $TiO_2$ and ITO films were kept constant at 5 and 100 nm, respectively. As-deposited ITO single layer films show an optical transmittance of 75.9%, while $ITO/TiO_2$ bi-layered films show a lower transmittance of 76.1%. However, as-deposited $ITO/TiO_2$ films show a lower resistivity ($9.87{\times}10^{-4}{\Omega}cm$) than that of ITO single layer films. In addition, the work function of the ITO film is affected by the $TiO_2$ buffer layer, with the $ITO/TiO_2$ films having a higher work-function (5.0 eV) than that of the ITO single layer films. The experimental results indicate that a 5-nm-thick $TiO_2$ buffer layer on the $ITO/TiO_2$ films results in better performance than conventional ITO single layer films.

• 한국진공학회지
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• 제6권1호
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• pp.69-76
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• 1997

순간 증착법으로 $Bi_{0.5}Sb_{1.5}Te_3$(p형)와 $Bi_2Te_{2.4} Se_{0.6}$(n형) 박막을 제조하여 두께와 어닐 링 조건에 따른 Seebeck 계수, 전기전도도, carrier 농도 및 이동도, 열전도도, 성능지수의 변화 등 열-전기적 특성을 조사하였다. 473K에서, 1시간 진공 열처리한 결과 p형과 n형의 성능지구는 각각 $1.3{\times}10^{-3}K^{-1}$ 및 $0.3{\times}10^{-3}K^{-1}$으로 향상되었으며 두께에 크게 의존하지 않았 다. 이런 성질을 갖는 열전 박막을 소자화한 박막 온도 센서를 유리와 Teflon기판 위에 제 조하였으며, 이들의 온도 변화에 대한 열기전력, 민감도 및 시간 상수 등 센서 특성을 측정 하였다. p 및 n형의 leg 폭 1mm$\times$길이 16mm인 박막 온도 센서의 경우, Teflon 기판일 때 좋은 성능을 나타내었으며, 민감도는 2.91V/W, 시간 상수는 28.2초이었다.