• 한국정밀공학회지
• /
• 제16권11호
• /
• pp.74-80
• /
• 1999

In this study, a stereolithography apparatus (SLA) prototype is used as a master model to be transformed into the silicone pattern by vacuum tool forming. The tool for the first prototype is fabricated by using this silicone pattern. Following this procedure, a temporary tool with metal powder and epoxy for wax injection is prepared for the die set of quick change type which consists of upper and lower base die나 and an insert die. The die set of quick change type appears to be very effective in casting operation by changing tools rapidly. The original wax pattern is formed through the die set, and is made of lost-was. Finally the lost-wax pattern is applied to investment casting. The final casting product is checked regarding its dimensional accuracy.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2000년도 춘계학술대회논문집A
• /
• pp.505-510
• /
• 2000

Vehicle performances such as fuel consumption and catalyst-out emissions are affected by a driving pattern, which is defined as a driving cycle with the grade in this study. We developed an algorithm to recognize a current driving pattern by using a neural network. And this algorithm can be used in adapting the driving control strategy to the recognized driving pattern. First, we classified the general driving patterns into 6 representative driving patterns, which are composed of 3 urban driving patterns, 2 suburban driving patterns and 1 expressway driving pattern. A total of 24 parameters such as average cycle velocity, positive acceleration kinetic energy, relative duration spent at stop, average acceleration and average grade are chosen to characterize the driving patterns. Second, we used a neural network (especially the Hamming network) to decide which representative driving pattern is closest to the current driving pattern by comparing the inner products between them. And before calculating inner product, each element of the current and representative driving patterns is transformed into 1 and -1 array as to 4 levels. In the end, we simulated the driving pattern recognition algorithm in a temporary pattern composed of 6 representative driving patterns and, verified the reliable recognition performance.

• 식물조직배양학회지
• /
• 제25권3호
• /
• pp.177-181
• /
• 1998

토마토에서 GUS 유전자를 가진 Agrobacterium을 이용하여 형질전환된 캘러스와 형질전환 되지 않은 캘러스의 peroxidase(POD)와 superoxide dismutase(SOD) 활성 차이를 조사하여 형질전환된 세포의 안전성평가의 기초자료로 삼고자 얻어진 결과는 다음과 같다. JA101 종자로부터 형성된 hypocotyl의 POD, SOD 비활성은 각각 23 unit/mg protein와 2,156 unit/mg protein로 공시품종 중 가장 높은 활성을 나타내었다. Hypocotyl 절편체로부터 유도한 캘러스 생장은 1mg/L 2,4-D의 농도에서 가장 좋았으며, 1 mg/L 2,4-D가 함유된 배지에서 유도된 캘러스에서 POD 와 SOD 비활성은 각각 47 unit/mg protein 와 95,786 unit/mg protein로 높게 나타났다. Agrobacterium과 hypocotyl 절편체와의 공동배양으로부터 형성된 캘러스중 21.6%의 형질전환된 캘러스를 얻을수 있었으며, 형질전환된 캘러스의 POD 비활성은 54 unit/mg protein로 형질전환 되지 않은 캘러스의 64 unit/mg protein보다 낮게 나타났고, SOD 비활성은 형질전환된 캘러스가 30,300 unit/mg protein로 형질전환되지 않은 캘런스의 37,077 unit/mg protein 보다 낮게 나타났다. 형질전환된 캘러스와 형질전환되지 않은 캘러스간의 isozyme pattern 차이는 인정할 수 없었다.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
• /
• pp.616-619
• /
• 2007

Nowadays, urbanized area expands its boundary, and distribution of urbanized area is gradually transformed into more complicated pattern. In Korea, SMA(Seoul Metropolitan Area) has outstanding urbanized area since 1950s. But it is ambiguous whether urban distribution is clustered or dispersed. This study aims to show the way in which expansion of urbanized area impacts on spatial distribution pattern of urbanized area. We use quadrat analysis, nearest-neighbor analysis and fractal analysis to know distribution pattern of urbanized area in time-series urban growth. The quadrat analysis indicates that distribution pattern of urbanized area is clustered but the cohesion is gradually weakened. And the nearest-neighbor analysis shows that point patterns are changed that urbanized area distribution pattern is progressively changed from clustered pattern into dispersed pattern. The fractal dimension analysis shows that 1972's distribution dimension is 1.428 and 2000's dimension is 1.777. Therefore, as time goes by, the complexity of urbanized area is more increased through the years. As a result, we can show that the cohesion of the urbanized area is weakened and complicated.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
• /
• pp.619-623
• /
• 1992

In pattern recognition, the conventional neural networks contain a large number of weights and require considerable training times and preprocessor to classify a transformed patterns. In this paper, we propose a constrained pattern recognition method which is insensitive to rotation of input pattern by various degrees and does not need any preprocessing. Because these neural networks can not be trained by the conventional training algorithm such as error back propagation, a novel training algorithm is suggested. As such a system is useful in problem related to calssify overse side and reverse side of 500 won coin. As an illustrative example, identification problem of overse and reverse side of 500 won coin is shown.

• 디지털콘텐츠학회 논문지
• /
• 제17권3호
• /
• pp.197-202
• /
• 2016

이 논문에서는 비정형 의료이미지 정형화 및 패턴 추출을 위해, 의료기기 또는 의료전문가로부터 생성 또는 감지되는 의료이미지 저장을 위한 데이터베이스 구축한다. 이러한 비정형 이미지의 특징을 정형화된 디지털 데이터로 변환한 후 정형화된 디지털 이미지 데이터로부터 의미있는 패턴 정보를 생성한다. 이러한 경험 기술 소개를 통해 많은 연구자들은 의료이미지 데이터베이스를 보다 쉽게 접근할 수 있고 다양한 분야에서 정형화된 의료이미지를 활용할 수 있다.

• 한국광학회지
• /
• 제2권2호
• /
• pp.83-88
• /
• 1991

공간불변(space-invariant) 패턴인식에 대한 연구는 여러 접근방식에서 많은 시도가 이루어지고 있다. 학습 이미지의 가중치 선형조합(weighted linear summation)에 의한 SDF(synthetic discriminant function) 필터를 이용한 패턴인식은 그 중의 한 방식으로서 꾸준히 많은 관심을 받고 있다. 본 논문에서는 off-axis 평면기준파의 각분할(angular multiplexing) 방식과 pseude-inverse 알고리듬에 의한 pSDF 필터를 결합하여 상관기를 구성하고 상관면에서의 상관반응을 관측하여, off-axis pSDF 공간정합필터가 유형분류에 유용함을 입증하고, 광상관기로의 적용가능성을 보여주고자 한다.

• 대한전기학회논문지:시스템및제어부문D
• /
• 제50권10호
• /
• pp.473-478
• /
• 2001

Image processings using the two-dimensional wavelet transform (2DWT) have been a very active research area in recent years because the 2DWT possess many good properties. However, the discrete 2DWT can not be used for pattern recognition directly because it does not have the translation property. In this paper, we show why conventional discrete two-dimensional wavelet transforms cannot be used for pattern recognitions directly. Then, we propose a new method that makes it possible to use discrete 2DWT to pattern recognition without modification of standard pyramidal algorithms. The main idea of our method is to postprocess the wavelet transformed images using the second-order neural network. To justify the validity of the method, evaluations with test images were performed. The effectiveness of the method can be shown by the evaluation results.

• KSBB Journal
• /
• 제19권4호
• /
• pp.291-294
• /
• 2004

박테리오신의 일종인 leucocin A로 형질전환된 효모가 보이는, B. subtilis에 대한 항균 활성을 파악하기 위하여 형질 전환되지 않은 효모와 형질전환된 효모를 배양하면서 시간별로 채취하여 광학밀도, 건조중량, 총단백질량, 단백질 분해효소 그리고 항균활성을 측정하였다. Leucocin A의 항균활성은 성장양상과 비례하였다. 배양초기에 비해 12시간 배양 후에 항균활성이 3배 이상 증가하는 것으로 나타났고, 이때 B. subtilis의 성장이 70.57% 감소하는 것으로 나타났다. 정지기 이후에는 항균활성이 급속히 감소하였는데, 이는 항균활성을 보이는 leucocin A가 단백질이고, 단백질 분해효소가 정지기 이후 증가한 것에 의한 것으로 사료되었다. 이 연구는 향후 식품산업 등에 사용할 수 있는 bacteriocin의 산업적 생산에 필요한 기초자료를 제공할 수 있을 것이다.

• 한국분말재료학회지
• /
• 제10권5호
• /
• pp.305-309
• /
• 2003

We report on the formation and chemical leaching of non-equilibrium $Al_{0.6}(Fe_{75}Co_{25})$ alloy produced by rod milling. X-ray diffractometry, transmission electron microscopy, differential scanning calorimetry, scanning electron microscopy, and vibrating sample magnetometry were used to characterize the as-milled and leached specimens. After 400 h, only the $Al_{0.4}Fe_{0.6}$ peak of the body-centered cubic type was present in the XRD pattern. The entire rod milling process could be divided into three different stages of milling: agglomeration, disintegration, and homogenization. The saturation magnetization, $M_s$ decreased with increased milling time, the $M_s$ of the powders before milling was about 113.8 emu/g, the $M_s$ after milling for 400 h was about 11.55 emu/g. Leaching of the Al in KOH of the Al at room temperature from the as-milled powders did not induce any significant change in the diffraction pattern. After the leached specimen had been annealed at $600^{\circ}C$ for 1 hour, the nanoscale crystalline phases were transformed into the bcc Fe, cubic Co, and $CoFe_2O_4$ phases. On cooling the specimen from 85$0^{\circ}C$, the degree of magnetization increased slightly, then increased sharply at approximately 364.8$^{\circ}C$, indicating that the bcc $Al_{0.4}Fe_{0.6}$ phase had been transformed to the Fe and Co phases.