• 제목/요약/키워드: Delta method

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An Automated System for Constant ${\Delta}K_{eff}$ Fatigue Crack Growth Testing through Real-time Measurement of Crack Opening Load (${\Delta}K_{eff}$ 제어 피로 균열 진전 시험 자동화 시스템에 관한 연구)

  • Shin, Sung-Chul;Song, Ji-Ho
    • Proceedings of the KSME Conference
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    • 2001.06a
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    • pp.447-452
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    • 2001
  • An automated system is developed to perform fatigue crack growth tests under constant effective stress intensity factor range ${\Delta}K_{eff}$. In the system, crack length and crack opening load are measured in real-time by using the unloading elastic compliance method. The system consists of two personal computers, an analogue electrical subtraction circuit, a stepping motor, a stepping motor driver, a PIO board, and the application software used to integrate the whole system. The performance of the developed system was tested and discussed performing constant ${\Delta}K_{eff}$ crack growth tests on a CT specimen of 7075-T6 aluminum alloy. The performance of the system is found to be strongly dependent on the accuracy of measurements of crack opening load. Besides constant ${\Delta}K_{eff}$ testing, the system is expected to be successfully applied for automation of various fatigue tests.

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Reduction Properties of $(La_{1-x}Sr_x)MnO_{3+\delta}$ Powder by GNP (GNP법에 의한 $(La_{1-x}Sr_x)MnO_{3+\delta}$ 분말의 환원특성)

  • Lee, Mi-Jai;Paik, Jong-Hoo;Kim, Sei-Ki;Park, Sang-Sun;Choi, Byung-Hyun;Lee, Kyung-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.11a
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    • pp.242-243
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    • 2005
  • In this study, (La,Sr)$MnO_{3+\delta}$ powder used cathode material for SOFC was synthesized with precursor by GNP and the properties of powder, crystal phase, electric properties and deoxidization properties with precursor were investigated. The synthesis powder was prepared when oxidant/fuel mole and pH were 1 and 1, respectively and the synthesis powder was synthesized by GNP method using nitrate solution or oxide solution as precursor. Deoxidization peak of the nitrate solution was appeared lower temperature than the oxide solution, at $450^{\circ}C$. In this result, synthesis (La,Sr)$MnO_{3+\delta}$ powder using nitrate solution with Mn excess was suitable cathode material for SOFC due to had higher deoxidization properties. Also synthesis (La,Sr)$MnO_{3+\delta}$ powder according to precursor had difference electrical conductivity according to influence sintering density and crystal phase with precursor. Specially, the synthesis method and starting material had effect on deoxidization properties for SOFC.

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A Study on Enhanced Self-Generation Supervised Learning Algorithm for Image Recognition (영상 인식을 위한 개선된 자가 생성 지도 학습 알고리듬에 관한 연구)

  • Kim, Tae-Kyung;Kim, Kwang-Baek;Paik, Joon-Ki
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.2C
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    • pp.31-40
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    • 2005
  • we propose an enhanced self-generation supervised algorithm that by combining an ART algorithm and the delta-bar-delta method. Form the input layer to the hidden layer, ART-1 and ART-2 are used to produce nodes, respectively. A winner-take-all method is adopted to the connection weight adaption so that a stored pattern for some pattern is updated. we test the recognition of student identification, a certificate of residence, and an identifier from container that require nodes of hidden layers in neural network. In simulation results, the proposed self-generation supervised learning algorithm reduces the possibility of local minima and improves learning speed and paralysis than conventional neural networks.

A Design of Delta-Average Queue Management Method for Supporting QoS in Wireless Sensor Networks (무선 센서 네트워크에서 QoS 제공을 위한 Delta-Average 큐 관리 기법 설계)

  • Yu Tae-Young;Kum Hyun-Tae;Jee Suk-Kun;Ra In-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2006.05a
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    • pp.446-450
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    • 2006
  • Recently, the advances on sensor technology increases the study on data processing oriented middleware. Usually, most of middleware uses the naive and delta method for queue management to process data effectively. But such a queue management method it is difficult to support guaranteeing of the requested quality of services because it simply discards the data in a queue when the overflow is occurred. To handle this problem, some methods for minimizing data volumes in a wireless sensor network have been studied, but most of them cause another problem that needs the huge processing time additionally with higher complexity of the proposed algorithm. In this paper, we propose a new method of delta-average queue management by applying the mean value to the exiting delta queue management method using the data differences to handle the problem of queue overflow. The proposed method has lower complexity than the others and increases the QoS of a WSN application by using mean value instead of using data discarding policy. In addition, it is designed to manage a queue effectively by controlling the range of data differences adaptively to the target sensor network environment.

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$\Delta$-Shaped Interpolation Algorithm for Displaying the Multi-Source Signal on the Flat Panel Display (FPD 상에서 다중 신호원을 디스플레이하기 위한 $\Delta$-Shaped 보간 알고리즘)

  • 박병기;최철호;박진성;권병헌;최명렬
    • Journal of Korea Multimedia Society
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    • v.2 no.1
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    • pp.89-98
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    • 1999
  • In this paper, we propose the delta-shaped interpolation method for displaying multi-source video signals on a-Si TFT LCD Panel. The proposed method can be implemented by using less circuits than the conventional methods. Thus it can be applied to the FPD(Flat Panel Display) system without any cost increase such as field memory cost. In order to compare the picture quality of the proposed method with that of the conventional methods, the computer simulation has been executed by checking PSNR, which is especially focused on the edge characteristics. The simulation results show that the proposed method is better than others from the point of view on the edge and local characteristics of the image. Finally, the characteristics and trade-off of the proposed method are discussed.

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Study of 3-Ketosteroid Dehydrogenase System Using Whole-cell-enzyme from Arthrobacter simplex

  • Park, Eun-Chung;Ryu, Dewey Doo-Young
    • YAKHAK HOEJI
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    • v.21 no.3
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    • pp.167-171
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    • 1977
  • A new assay method for delta-l-dehydrogenated-3-ketoco-rticosteroid in the presence of proteinous material or whole-cell-enzyme and 3-ketocorticosteroid has been developed. This method makes use of the linear relationship between the ratio of absorbances at 265 nm and at 242 nm and the fractional concentration of delta-1-3-ketosteroid. Theoretical values were calculated based on the absorbances of proteinous material at fixed concentrations of the 3-ketosteroid and delta-1-dehydrogenated-3-ketosteroid. The values obtained experimentally showed good agreement with the values obtained experimentally showed good agreement with the values theoretically predicted. The new assay method developed for the steroid mixtiure containing proteinous material is of some practical importance. The use of such assay method enables one to determine the enzyme activity and the rate of enzyme reaction or conversion rather quickly, easily and accurately. By the use of this assay method, the reaction kinetics of whole-cell-enzyme has also been studied. It was found that it followed the simple Michaelis-Menten type enzyme kinetics. Also the reversibility of this reaction with actively metabolizing cell was examined. It was found that delta-l-dehydrogenated-3-ketosteroid could not be hydrogenated reversibly to 3-ketosteroid by this enzyme system.

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Threshold Voltage Control of a-Si TFT by Delta Doping of Phosphorous

  • Soh, Hoe-Sup;Kim, Cheol-Se;Kim, Eung-Do
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08b
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    • pp.1165-1167
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    • 2007
  • Delta doping method can separate the threshold voltage control region from the charge transport region in a-Si TFT, whereby the threshold voltage of a TFT could be modified. Threshold voltage could be changed by delta doping, while field effect mobility was estimated to be 80% of that of standard TFT.

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A Study on Auto-Tuning Method of learning Rate by Using Fuzzy Logic System (퍼지 논리 시스템을 이용한 학습률 자동 조정 방법에 관한 연구)

  • 주영호;김태영;김광백
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2003.05a
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    • pp.484-489
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    • 2003
  • 본 논문에서는 역전파 알고리즘의 성능 개선을 위해 퍼지 논리 시스템을 이용한 학습률 자동 조정 방법을 제안한다. 제안된 방법은 목표값과 출력값의 차이에 대한 절대값이 $\varepsilon$ 보다 적거나 같으면 정확성으로 분류하고 크면 부정확성으로 분류한다. 정확성의 총 개수를 퍼지 논리 시스템에 적용하여 학습률과 모멘텀을 동적으로 조정한다. 제안된 방법을 XOR 문제와 숫자패턴 문제에 적용하여 실험한 결과, 기존의 역전파 알고리즘, 모멘텀 방식, Jacob의 delta-bar-delta 방식보다 성능이 개선됨을 확인하였다.

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C-Glucuronide from O-Glucuronyl Trichloroacetimidate

  • Baek, Seung-Hwa
    • Bulletin of the Korean Chemical Society
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    • v.12 no.6
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    • pp.604-606
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    • 1991
  • From O-glucuronyl trichloroacetimidate (4) and ${\Delta}^6$-tetrahydrocannabinol (5), the C-glucuronide of ${\Delta}^6-tetrahydrocannabinol({\Delta}^6-THC)$ (7) was obtained using mild Lewis acid catalysis. The known method for the synthesis of C-glucuronide from 1-O-unprotected glucuronide provided low chemical yields. The C-glucuronide of ${\Delta}^6-THC$ was obtained through inversion of configuration at the anomeric center in O-glucuronyl trichloroacetimidate (4).

A STUDY ON THE CHANCES OF THE SOFT TISSUE PROFILE FOLLOWING ORTHODONTIC TREATMENT BY DIGITAL SUBTRACTION METHOD (교정치료에 따른 측모 연조직의 변화에 관한 계수공제 영상측정법적 연구)

  • Cho, Won-Tak;Yu, Dong-Hwan
    • The korean journal of orthodontics
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    • v.27 no.3 s.62
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    • pp.411-420
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    • 1997
  • The propose of this study was to quantify the changes of soft tissue profile following orthodontic treatment and to evaluate the relationship of those to the skeletal elements. Pre-and post-treatment lateral cephalometric head films of 40 cases(20 extraction cases, 20 non-extraction cases) were traced, and the changes following treatment were measured and quantified by digital subtraction method, and statisticall analyzed. The obtained results were as follows; 1. in extraction group, the change of upper lip area(UL) was $558.60\pm355.17$ pixels, that of lower lip area(LL) was $941.15\pm364.07$ pixels. But, in non-extraction group the change of uper lip area(UL) was $125.65\pm404.16$ pixels, that of lower lip area(LL) was $104.05\pm440.93$ pixels, which was significantly lesser than those in extraction group. 2. In extraction group, there was significant correlationship between upper lip area change(UL) and difference of upper incisor point(${\Delta}UIP$). Lower lip area change(LL) was significantly correlated with difference of upper incisor(${\Delta}UIP$), difference of Franlrfort upper incisor angle(${\Delta}FUIA$) or difference of interincisal angle(${\Delta}IIA$). 3. In extraction group, the ratio of difference of upper incisor point(${\Delta}UIP$) to difference of labrale superius(${\Delta}LSP$) was 1.68; difference of lower incisor point(${\Delta}LIP$) to difference of labrale inferius(${\Delta}LI$) was 1.19; difference of upper incisor point(${\Delta}UIP$) to increment in upper lip thickness(${\Delta}TUL$) was 1.95. 4. In non-extraction group, there was a significant correlationship between upper lip area change(UL) and difference of upper incisor point(${\Delta}UIP$).

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