지문워터마크를 이용한 공격에 강인한 DCT 워터마킹 알고리즘

이주신 청주대학교 산업과학연구소 2003 産業科學硏究 Vol.21 No.1

In this paper, a robust DCT watermarking algorithm under attacks using a fingerprint Watermark is proposed for protecting copyrighters. A watermark is created by DCT process after it is segmented a copyrighter's fingerprint into blocks of 8×8 size. A watermarked image is created by adding the watermark to an original image. The watermark is inserted into an original image in the frequency domain, and it is reconstructed by IDCT process. DFT transform is used for transforming into frequency domain. To investigate the propriety of the proposed scheme, it is experimented with a LENA standard image. From the results of the experiment, PSNR of the watermarked images is 92.76 dB. Watermark reconstruction results are shown that the reconstructive rate is 91.97% in image scale-down, 88.46% in image rotation, 97.61% in image added Salt & Pepper noise, and 90.71% in JPEG lossy compression image.

화상추적에 관한 연구

李周信,宋宇永 淸州大學校 1982 論文集 Vol.15 No.2

This paper showse that In the case of the image restoration need not be in signal processing, the data of the still picture can be compressed of image. the still picture can be realizied of the digital signal and picture recognition by the simple method. Using the sampling technique in with sample is obtained by averaging a samall portion of the picture. The experimental results, This system is not only a picture compression but The moving image described by digital signal. It is easy to see that the digital signal in order to tracking target is obtained by using this system.

Sm₂O₃doped CeO₂의 미분말 합성 및 소결특성

김동완,박민우,이주신 경성대학교 2000 論文集 Vol.21 No.1

10mol% Sm₂O₃ CeO₂fine powders were synthesized by the coprecipitation method and then their powder characteristics and sintering behavior were studied. The characterization of powders has been investigated using thermogravimetry and differential thermal analysis for thermal analysis, X-ray diffraction for phase identification, Brunauer-Emmett-Teller, X-ray diffraction-line broadening and transmission electron microscopy for particle size and morphology determination. The sintering behavior were investigated by means of the sintering density measurements. The characteristics of powders prepared by the coprecipitaion method and their sintering behavior are discussed.

산소이온전도체용 CaO 첨가 안정화 ZrO₂의 미분말 합성 및 그 소결특성

박정일,이주신 慶星大學校 1996 論文集 Vol.17 No.2

In order to fabricate solid electrolyte CaO-stabilized ZrO₂ of high density sintered body economically, 13mol% CaO-stabilized ZrO₂powders were synthesized by the coprecipitation method. The characteristics and sintering behavior of fine powders were investigated. The precipitates had the specific surface area of 193㎡/g, and apperaed to be fine and spherical primary particles with a size of approximately 5nm. The crystallization temperature of CaO-stabilized ZrO₂was 462℃. The tetragonal phase was stable in the low calcining temperature regions, and the cubic zirconia solid solution was formed from above 1200℃ through an intermediate stage of formation of CaZrO₃. By introducing fine powers washed with alcohol and ball-milling prccess after calcination, the sintered body was possible to attain the value of above 92% of the theoretical density at low temperature of 1200℃.

3차원 이동물체의 변위평가를 위한 스테레오 비젼시스템 설계에 관한 연구

이주신 한국통신학회 1990 韓國通信學會論文誌 Vol.15 No.12

This paper described design and implementation of stereo vision system, and also, proposed method for displacement estimation of 3-D moving object using this system. The extraction of moving object is obtained by difference image algorithm. Geometrical position of 3-D moving object is calculated form the mapping of center area of two's 2-D object. 3-D coordinate position produced space depth, moving velociity, distance, moving track and proved displacement estimation of 3-D moving object. 본 논문은 스테레오비젼 시스템을 설계 제작하고, 제작된 시스템을 가지고 3차원 이동물체의 변위평가 방법을 제안하였다. 이동물체의 추출은 차영상 알고리즘에 의해 추출하고, 3차원 이동물체의 기하학적인 위치좌표는 2개의 2차원 물체의 면적중심을 합성시켜 구하였다. 3차원 이동물체의 범위평가는 합성된 3차원 좌표값에 의해서 물체의 이동속도 및 거리, 이동궤적, 카메라와 물체 사이의 공간거리를 산출하여 입증하였다.

단일 이동물체 추적을 위한 능동적인 스테레오 비젼 시스템 구현

이주신 청주대학교 산업과학연구소 1996 産業科學硏究 Vol.14 No.-

In this paper, we present the stereo vision system implemented to extract single moving objects, and the improved EDC(Equi-Depth Contour) algorithm for an edge detection. The simulation is proved the active tracking and the reconstruction of 3-D moving objects. We capture images with two line light sources. So, the brightness of image plane can be minimized under 8% As a result, we improve blurring of moving objects. Then, found that our implementation can tract the moving objects having the velocity of maximum 793.3 ㎜/sec activity. The edge detection algorithm of the improved EDC is not necessary to thinning process for detection of feature parameters. we can find that our algorithm is good for 3-D reconstruction.

High-energy ball milling process에 의해 제조된 Ga₂0₃첨가 Ce_(0.8)Gd_(0.2)O_(1.9) 세라믹스의 전기적특성

이주신 경성대학교 공학기술연구소 2010 공학기술연구지 Vol.16 No.-

The electrical property of Ga₂0₃-added Ce_(0.8)Gd_(0.2)O_(1.9) ceramics was investigated. The gadolinia-doped ceria powders were prepared by the high-energy ball milling process using commercially available powders. Dense Ce_(0.8)Gd_(0.2)O_(1.9) ceramics with 97% of the theoretical density could be obtained by sintering of the milled mixture with 0.5 mol% Ga₂0₃ addition at 1250℃ for 5 h. Total conductivity of 0.5 mol% Ga₂0₃-added specimen showed the maximum conductivity of 2.88x10^(-3) Ω^(-1)·cm^(-1) at 500℃. Pure Ce_(0.8)Gd_(0.2)O_(1.9) ceramics needed to be sintered at 1600℃ in order to obtain an equivalent theoretical density and conductivity. Introduction of high-energy ball milling process and Ga₂0₃ doping had a good effect on the electrical conductivity of gadolinia-doped ceria.

Stereo Vision System에 의한 3차원 이동물체의 변위평가

이주신 청주대학교 산업과학연구소 1989 産業科學硏究 Vol.7 No.-

Stereo Vision System have been used to instrument that position of 3-D moving object and recognition of 3-D object can extract information. This paper describes displacement estimate of 3-D moving object used to Stereo Vision System. The extraction of moving object is done by difference image between background image and current image, and then calculated the center of object area. Coordinate position of 3-D moving object is calculated by matching of two with 2-D moving object position. Displacement estimation of 3-D moving object can accomplish by the value of geometrical 3-D coordinate. The results show that from position 3-D moving object, the moving object velocity, moving distance and tracking was simulated eva1uating.

출발 Si 분말의 입자크기에 따른 Sintered RBSN의 기계적특성 변화

이주신,문지훈,한병동,박동수,김해두 한국세라믹학회 2001 한국세라믹학회지 Vol.38 No.8

출발원료 Si 분말의 입자크기를 다양하게 하여 질화반응 및 가스압 소결시 입자크기에 따른 산소함량의 차이에서 나타나는 상변화와 그로 인한 치밀화 거동, 미세구조 발달 및 기계적 특성에 대하여 고찰하였다. 145$0^{\circ}C$의 질화반응에서는 조대분말을 사용한 경우가 미세분말을 사용한 경우보다 높은 질화율을 나타냈으며, 각 분말크기에 따른 native oxide의 함량차에 따라 각기 다른 2차 결정상들이 검출되었다. 조대분말을 사용한 경우에는 제 2상의 석출로 인한 액상량의 부족으로 고온의 소결온도에서도 치밀화를 이루지 못해 낮은 강도값을 나타내었다. 한편, 미세분말을 사용한 경우에는 질화반응 후 석출된 제 2상이 소결온도가 증가함에 따라 용융되면서 치밀화를 이루어 높은 강도값을 나타내었다. 높은 강도값은 미세분말을 사용한 시편들에서 얻어졌으나 높은 파괴인성값은 상대적으로 큰 분말을 사용한 시편들에서 얻어졌는데, 이는 미세한 입자들로 구성된 기지상 내에 잘 발달된 주상정 입자들을 갖는 미세구조에 기인된 것으로 사료된다.

산소이온전도체 CaO 안정화 ZrO₂에의 Al₂O₃첨가효과

최용규,이주신 경성대학교 생산기술연구소 1997 생산기술연구지 Vol.4 No.-

The effects of Al₂O₃additions on sintering behavior and electrical conductivity of 13 mol% CaO-stabilized ZrO₂were systematically investigated from the following aspects: the variation in sintering density, the variation in grain size, the forms and existence position of Al₂O₃in ZrO₂and the variation in resistance. The powders of composition [??, (×=0, 0.01, 0.02, 0.03, 0.05)] were synthesized by the coprecipitation method. The synthesized powders were uniaxially pressed at 1000㎏/㎝²,and the pressed pellets were sintered at 1400℃ for 5hr. According to the result of SEM and XRD analysis, the solubility limit of Al₂O₃on 13 mol% CaO-stabilized ZrO₂can estimated to be nearly 1 mol%. Addition of 1 mol% Al₂O₃causes the increment on grain growth, and it brings the increment of the sintered density. The electrical conductivity is also increased with increasing Al₂O₃content up to 1 mol%. It is suggested that soluble and insoluble Al₂O₃have opposite effects on sintering behavior and electrical conductivity.