• Title/Summary/Keyword: Roberts

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Modeling Two-stage Choice Process (2단계 선택과정의 모형화)

  • 박상준;한민희
    • Journal of the Korean Operations Research and Management Science Society
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    • v.25 no.2
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    • pp.77-86
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    • 2000
  • Consumers facing a large number of brands to choose from are known to use simplified heuristic to screen a set of relevant brands called the consideration set from the whole alternatives, Purchase decisions are then made from the brands in the consideration set, Two approaches have been suggested to model the two-stage choice process., One is to treat the con-sideration set as a crisp set (e.g Roberts and Lattin 1991) The other is to treat the set as a fuzzy set (e.g. Fortheringham 1988) The paper empirically compares the two types of models using data for soft drinks sneakers and departments. The results show that a model employing the crisp set approach fits the data better than that with the fuzzy set approach and better than a single-stage choice logit model.

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Development of P-OLED Materials For Displays and Lighting

  • Brown, Scott;Cass, Michael;Conway, Natasha;Grizzi, Ilaria;McKiernan, Mary;Roberts, Matthew;Tsubata, Yoshiaki;Sekine, Chizu;Yamada, Takeshi;Wilson, Richard
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08a
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    • pp.431-434
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    • 2007
  • Rapid progress has been made in the development of commercially viable Light Emitting Polymer (LEP) materials for display and lighting applications. This presentation will focus on: ${\bullet}$ Degradation studies that have led to the design of new and improved materials ${\bullet}$ Recent lifetime and efficiency results for red, green, blue, and white polymers ${\bullet}$ Challenges of formulating inks that can be used in a production environment

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General Properties of Quantization Systems with a Stochastic Reference (Stochastic reference를 가진 량자화 시스템의 일반적인 성질)

  • 한선신
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.18 no.2
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    • pp.44-53
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    • 1981
  • This paper deals with two quantization systems with a stochastic refernce and gives the unified statical properties of the two systems. The conditions are derived for the invariance of the output quantized signal with respect to the imput signal for the two systems and it is shown that they are same. The correlation function by a polarity method using stochastic reference signals is show to be a special case of the general properties derived here. We have also shown that the classical stochastic computing is derived from the general properties of the first system and that L.G. roberts has used a special characteristic of the general properties of the second system in his image processing.

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Efficient variable BBM template for color image's edge detection (칼라영상의 에지 검출을 위한 효율적인 가변 BBM템플릿)

  • 백영현;변오성;문성룡
    • Proceedings of the Korea Multimedia Society Conference
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    • 2003.05b
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    • pp.385-388
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    • 2003
  • 영상의 에지는 입력 영상에 대한 중요 정보들을 가지고 있으며, 에지 추출은 영상인식의 성능을 좌우하는 중요 요소이다. 영상 에지 추출은 영상 분할의 첫 번째 단계이며, 영상의 구성을 결정하기 위해서 화소들을 하나의 영역으로 만드는데 사용되고 있다. 또한 에지 강도를 갖고 있는 모든 에지들을 검출하기 위해 많은 방법들이 제안되었다 기존의 에지 짐출은 흑백영상의 명암도의 변화에 국한되어 있었다 그러나 칼라영상을 이용하여 에지를 추출하는 경우에는 흑백영상보다 이용할 수 있는 정보가 많을 뿐 아니라 인간의 시각체계와도 유사하여 보다 나은 에지 추출을 기대할 수 있다. 본 논문에서는 칼라영상에서 직접적으로 얻을 수 있는 RGB 정보 중 광도를 분리하여 사용하는 YCbCr성분을 이용하여, 기존의 기울기연산자나 표면접합 템플릿에 의한 에지 추출이 아닌 3$\times$3 마스크안의 데이터값의 차에 따라 가변적으로 변하는 BBM템플릿을 제안하였다. 제안된 가변 BBM템플릿은 모의 실험한 결과 기존의 Sobel, Preweet, Roberts 같은 연산 템플릿보다 성능이 우수함을 확인하였다.

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The Design of the IIR Differintegrator and its Application in Edge Detection

  • Jain, Madhu;Gupta, Maneesha;Jain, N.K.
    • Journal of Information Processing Systems
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    • v.10 no.2
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    • pp.223-239
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    • 2014
  • New IIR digital differintegrators (differentiator and integrator) with very minor absolute relative errors are presented in this paper. The digital integrator is designed by interpolating some of the existing integrators. The optimum value of the interpolation ratio is obtained through linear programming optimization. Subsequently, by modifying the transfer function of the proposed integrator appropriately, new digital differentiator is obtained. Simulation results demonstrate that the proposed differintegrator are a more accurate approximation of ideal ones, than the existing differintegrators. Furthermore, the proposed differentiator has been tested in an image processing application. Edges characterize boundaries and are, therefore, a problem of fundamental importance in image processing. For comparison purpose Prewitt, Sobel, Roberts, Canny, Laplacian of Gaussian (LOG), Zerocross operators were used and their results are displayed. The results of edge detection by some of the existing differentiators are also provided. The simulation results have shown the superiority of the proposed approach over existing ones.

The performance evaluation of car license plate edge detection by various edge detectors (다양한 에지 검출기에 의한 차량 번호판의 에지 검출 성능 평가)

  • Lee, Seok-Hee;Song, Young-Jun;Ahn, Jae-Hyeong
    • Proceedings of the Korea Information Processing Society Conference
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    • 2004.05a
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    • pp.773-776
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    • 2004
  • 본 논문에서는 에지 검출기에 의해 다양한 명암이 존재하는 차량 번호판 영역의 사각형 에지를 검출시 사용되는 소벨 및 Prewitt, Roberts, 가우시안의 라플라시안, 그리고 Canny 검출기를 사용하여 처리 속도와 에지 검출의 정확성을 실험하여 각 연산자의 성능을 평가하였다. 기존의 Sobel 에지 검출기는 적응적 임계값을 구하지 않으면 다양한 조명의 영향에 강인하지 못하다. 또한 Canny 에지 검출기는 조명의 영향에 강인하기는 하나, 계산량이 Sobel 보다는 많아 처리 속도가 느리다. 색상에 의해 번호판 후보 영역을 추출한 후 에지 검출기 번호판 내의 명암이 둘 이상으로 차량 번호판 영역에 대해서, 다양한 에지 검출기를 적용하여 속도와 에지 검출 성능을 비교 평가하고자 한다.

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Psychometrics of Task Self-Efficacy Scale for Korean Elderly (노인의 일상활동수행에 대한 자기효능척도의 신뢰도 및 타당도 평가)

  • ;;;;Beverly L. Roberts
    • Journal of Korean Academy of Nursing
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    • v.27 no.4
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    • pp.831-842
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    • 1997
  • The purpose of the study was to test the reliability and validity of the Korean version of Task Self-Efficacy Scale for activities of dally living (ADL). The Task Self-Efficacy Scale was developed by Roberts(1996) for low-intensity exercise study with older people to predict their performance of ADL. The scale was translated and back translated by bilingual persons, and then was modified to resolve variations in the translations. The Korean version of Self-Efficacy Scale for ADL was then administered to 193 elderly people including 95 hospitalized patients and 98 outpatients or healthy people. Face to face interview was used to fill out the structured questionnaire, and each interview took approximately 30 minutes. The subjects for the study were 80 women and 112 men with an age range of 65 to 95 years(M=71 years) of whom 82.6% classified themselves as moderate or quite active Most subjects(80.2%) had an education level of elementary school or less. The Self-Efficacy Scale for ADL is measured on a 0 to 10 VAS, assessing three areas of ADL : self care activities, household tasks, and motor tasks. The higher the score is, the higher person's confidence in performing ADL. Psychometric testing revealed that the scale was found to be internally consistent, showing a Cronbach's alpha of .97 The scale was significantly correlated with subjects' level of activity and subjective assessment of their health status. Moderate correlation with health-related hardiness scale also supported the validity. Factor analysis was performed to confirm whether the scale represents the three sub-areas as suggested in the literature. The results of the factor analysis led to a three factor solution according to Kaiser's criterion, but the items were not strongly and cleanly loaded for the third factor. This can be explained in that, among the three sub-ADL areas of the self-efficacy scale, the areas of self care activities and household tasks seem to have similar levels of difficulty in performance with not enough differences for the self-efficacy scale to distinguish between the two areas. Therefore, one factor solution was suggested since ADL can be seen as a unit of activities at similar level of difficulty in performance. One factor solution explained 68.1% of variance of the 19-item scale and all items were correlated over .6 with the factor, showing that the selected factor solution fits the model. The results indicated that the Korean version of Task Self-Efficacy Scale for ADL was reliable and valid in producing useful information to evaluate the effects of various interventions toward promoting health and quality of life for elderly people.

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Missionary Public Health Nursing of Korea during Japanese Colonial Period (일제시대 선교회의 보건간호사업에 대한 역사적 연구)

  • Yi, Ggod-Me;Kim, Hwa-Joong
    • Research in Community and Public Health Nursing
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    • v.10 no.2
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    • pp.455-466
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    • 1999
  • Western missionary nurses practiced in Korea from 1891. and the first trial to begin missionary public health nursing service in 1909 could not put into practice for short of nursing staff and budget. The main focus of missionary medical practice was not in public health program but in the management of missionary hospitals. A few of missionary western R.N. tried district nursing in 1910s. but their activities were personal and focused on the rescue of poor and sick patients. In 1917 the North American Methodist Church dispatched R.N. Elizabeth S. Roberts to begin district nursing in Korea. Roberts began maternal and child district nursing service. Her service was focused on teaching the method of bringing up children. bathing service, and home visiting for delivery. She could not but stop district-nursing service in 1918 to serve for a hospital in Siberia. The North American Methodist Church dispatched a few of R.N. to Korea in early 1920s and the missionary public health nursing of Korea could be activated. R.N. E. T. Rosenberger began public health nursing program in Seoul with Korean graduate nurse, Shin-gwang Han, and missionary M.D. Hall. Their public health nursing program was focused on maternal and childcare. They did home visiting in the morning, and served at a well baby clinic in the afternoon. The first baby competition began in 1925. and contributed to the teaching the method of bringing up children. They expanded public health nursing activity to school health nursing and milk station. Their public health nursing program was such a success that In 1929 Severance hospital. Eastgate Hospital. Taehwa Social Evangelistic center organized Seoul Child Health Union. Maren P. Bording, another missionary R.N. and midwife dispatched by the North American Methodist Church began public health nursing program at Kongjoo in 1924. Her program was focused on the maternal and childcare and close to that of Seoul. She started the first milk station in Korea in 1926. As she was a midwife and could get M. D. license in Korea, her program was more focused on maternal care than that of Seoul. The first day nursery school in Korea and the first graduate course for public health nursing in Korea began at Kongjoo in 1930. As the city of Choongcheongnam Province moved from Kongjoo to Daejeon in 1932, missionary public health nursing service in Kongjoo extended to Daejeon. There were lots of public health nursing program in Korea in 1920s and 1930s by missionary western nurses and Korean nurses. There were 13 missionary public health-nursing center in Korea in 1932. But in the late 1930s. Japan extended colonial war and drove out western missionaries. The missionary service in Korea was daunted. and the missionary public health nursing service could not but shrink.

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Immunochemical Studies for the Characterization of Purified $(Na^+,\;K^+)-ATPase$ and Its Subunits with a Special Reference of Their Effect on Monovalent Cation Transport in Reconstituted $(Na^+,\;K^+)-ATPase$ Vesicles

  • Rhee, H.M.;Hokin, L.E.
    • The Korean Journal of Pharmacology
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    • v.26 no.1
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    • pp.35-49
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    • 1990
  • A highly purified $(Na^+,\;K^+)-ATPase$ from the rectal gland of Squalus acanthias and from the electric organ of Electrophorus electricus has been used to raise antibodies in rabbits. The 97,000 dalton catalytic subunit and glycoprotein derived from the rectal gland of spiny shark were also used as antigens. The two $(Na^+,\;K^+)-ATPase$ holoenzymes and the two shark subunits were antigenic. In Ouchterlony double diffusion experiments, these antibodies formed precipitation bands with their antigens. Antibodies prepared against the two subunits of shark holoenzyme also formed precipitation bands with their antigens and shark holoenzyme, but not with eel holoenzyme. These observations are in good agreement with inhibitory effect of these antibodies on the catalytic activity of $(Na^+,\;K^+)-ATPase$ both from the shark and the eel, since there is very little cross-reaction between the shark anticatalytic subunit antibodies and the eel holoenzyme. The maximum antibodies titer of the anticatalytic subunit antibodies is found to be 6 weeks after the initial single exposure to this antigen. Multiple injections of the antigen increased the antibody titer. However, the time required to produce the maximum antibody titer was approximately the same. These antibodies also inhibit catalytic activity of $(Na^+,\;K^+)-ATPase$ vesicles reconstituted by a slow dialysis of cholate after solubilization of the enzyme in a presonicated mixture of cholate and phospholipid. In these reconstituted $(Na^+,\;K^+)-ATPase$ vesicles, effects of these antibodies on the fluxes of $Na^+$, $Rb^+$, and $K^+$ were investigated. Control or preimmune serum had no effect on the influx of $^{22}Na^+$ or the efflux of $^{86}Rb^+$. Immunized sera against the shark $(Na^+,\;K^+)-ATPase$ holoenzyme, its glycoprotein or catalytic subunit did inhibit the influx of $^{22}Na^+$ and the efflux of $^{86}Rb^+$. It was also demonstrated that these antibodies inhibit the coupled counter-transport of $Na^+$ and $K^+$ as studied by means of dual labeling experiments. However, this inhibitory effect of the antibodies on transport of ions in the $(Na^+,\;K^+)-ATPase$ vesicles is manifested only on the portion of energy and temperature dependent alkali metal fluxes, not on the portion of ATP and ouabain insensitive ion movement. Simultaneous determination of effects of the antibodies on ion fluxes and vesicular catalytic activity indicates that an inhibition of active ion transport in reconstituted $(Na^+,\;K^+)-ATPase$ vesicles appears to be due to the inhibitory action of the antibodies on the enzymatic activity of $(Na^+,\;K^+)-ATPase$ molecules incorporated in the vesicles. These findings that the inhibitory effects of the antibodies specific to $(Na^+,\;K^+)-ATPase$ or to its subunits on ATP and temperature sensitive monovalent cation transport in parallel with the inhibitory effect of vesicular catalytic activity by these antibodies provide direct evidence that $(Na^+,\;K^+)-ATPase$ is the molecular machinery of active cation transport in this reconstituted $(Na^+,\;K^+)-ATPase$ vesicular system.

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Comparative analysis of detonation velocity in determining product composition for high energetic molecules using stoichiometric rules (화학 양론적 규칙으로 고에너지 물질의 폭발 생성물 조성 결정에 따른 폭발속도 비교분석)

  • Kim, Hyun Jeong;Lee, Byung Hun;Cho, Soo Gyeong;Lee, Sung Kwang
    • Analytical Science and Technology
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    • v.30 no.6
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    • pp.405-410
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    • 2017
  • High energetic materials (HEMs) have been used in fuels, civil engineering and architecture as well as military purposes such as explosives and propellants. The essential process for the development of new energetic compounds is to accurately calculate its detonation performances. The most typical equation for calculating the explosive performance is the Kamlet-Jacobs (K-J) equation. In the K-J equation, the parameter such as the number of moles of gaseous products at the explosion, the average molar mass of gas products, and the explosion heat greatly affect the explosion performance. These depend on the product composition for the detonation reaction. In this study, detonation products of 65 high energetic molecules (HEMs) were calculated from the various rules such as Kamlet-Jacobs, Kistiakowsky-Wilson, modified Kistiakowsky-Wilson, Springall-Roberts rules to calculate more accurate detonation velocity (Dv). In addition, they were applied to five kinds of detonation velocity equations proposed by K-J, Rothstein, Xiong, Stine and Keshavarz. The mean absolute error and root mean square error of HEMs were obtained from experimental and calculated velocity value for each method. The K-J and Xiong equation that is slightly complex showed a lower mean absolute error than the simple Rothstein and Keshavarz equation. When the mod-KW rule was applied to the Xiong equation, the detonation velocities were the most accurate. This study compared the various method of calculating the detonation velocity of HEMs to obtain accurate HEMs performance.