• Title/Summary/Keyword: difference-in-differences method

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A Study on the Influence of Environmental Education and Environmental Consciousness to the Environmental Behavior (환경교육과 환경의식이 환경보전 행동에 미치는 영향에 관한 연구)

  • 최남숙
    • Journal of the Korean Home Economics Association
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    • v.32 no.5
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    • pp.29-44
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    • 1994
  • It is an urgent time to give impetus to an ecological understanding of relationship between man and environment and to promote an action to preserve environment. This paper is to examine factors which give influence to environmental education environmental consciousness and environmental behavior of housewives. The subjects of this study are 806 Seoulite housewives. A questionaire is used as the survey method and the statistical methods such as frequency percentage ANOVA multiple regression path analysis have been applied for research. Major findings are summarized as follows: Major findings are summarized as follows: When environmental education program is relatively low differences are shown according to variables of age, education and occupation. Second, when environmental consciousness is high differences are shown according to variables of age education income and housing. Third when environmental behavior is low group difference is shown only according to age. Relative influence to environmental behaviour is shown in the order of spare-life type environmental education environmental consciousness socio-oriented type fashion-oriented type and age difference.

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Unsupervised Multispectral Image Segmentation Based on 1D Combined Neighborhood Differences (1D 통합된 근접차이에 기반한 자율적인 다중분광 영상 분할)

  • Saipullah, Khairul Muzzammil;Yun, Byung-Choon;Kim, Deok-Hwan
    • Proceedings of the Korea Information Processing Society Conference
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    • 2010.11a
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    • pp.625-628
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    • 2010
  • This paper proposes a novel feature extraction method for unsupervised multispectral image segmentation based in one dimensional combined neighborhood differences (1D CND). In contrast with the original CND, which is applied with traditional image, 1D CND is computed on a single pixel with various bands. The proposed algorithm utilizes the sign of differences between bands of the pixel. The difference values are thresholded to form a binary codeword. A binomial factor is assigned to these codeword to form another unique value. These values are then grouped to construct the 1D CND feature image where is used in the unsupervised image segmentation. Various experiments using two LANDSAT multispectral images have been performed to evaluate the segmentation and classification accuracy of the proposed method. The result shows that 1D CND feature outperforms the spectral feature, with average classification accuracy of 87.55% whereas that of spectral feature is 55.81%.

A Study on Adaptive Knowledge Automatic Acquisition Model from Case-Based Reasoning System (사례 기반 추론 시스템에서 적응 지식 자동 획득 모델에 관한 연구)

  • 이상범;김영천;이재훈;이성주
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2002.05a
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    • pp.81-86
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    • 2002
  • In current CBR(Case-Based Reasoning) systems, the case adaptation is usually performed by rule-based method that use rules hand-coded by the system developer. So, CBR system designer faces knowledge acquisition bottleneck similar to those found in traditional expert system design. In this thesis, 1 present a model for learning method of case adaptation knowledge using case base. The feature difference of each pair of cases are noted and become the antecedent part of an adaptation rule, the differences between the solutions in the compared cases become the consequent part of the rule. However, the number of rules that can possibly be discovered using a learning algorithm is enormous. The first method for finding cases to compare uses a syntactic measure of the distance between cases. The threshold fur identification of candidates for comparison is fixed th the maximum number of differences between the target and retrived case from all retrievals. The second method is to use similarity metric since the threshold method may not be an accurate measure. I suggest the elimination method of duplicate rules. In the elimination process, a confidence value is assigned to each rule based on its frequency. The learned adaptation rules is applied in riven target Problem. The basic. process involves search for all rules that handle at least one difference followed by a combination process in which complete solutions are built.

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A Study on the Related Factors and the Change after Foot-reflexo-massage Education Program for Diabetic Patients (당뇨병 환자의 발반사요법 교육프로그램 후 발관리지식, 자가간호행위, 생리적지표의 변화 및 관련요인분석)

  • Lee, Young-Hee
    • Korean Journal of Adult Nursing
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    • v.16 no.2
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    • pp.222-232
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    • 2004
  • Purpose: The purpose of this study was to identify the change in foot care knowledge, self care behavior, and physiologic indexes after foot reflexomassage education program, and the related factors. Method: Data were collected from 20 patients who were visited out patients clinic. The change and difference were analyzed with non-parametric statistics. Result: There were significant differences in foot care knowledge(P=.001), self care behavior(P=.000), dosalis pedis blood flow volume (P=.011), skin temperature of foot(P=.001), dorsalis pedis pulse(P=.000), capillary filling time of foot (P=.000) between pre and post. The level of changes of foot care knowledge was significant differences according to admission experience (P=.049), and negative related to systolic blood pressure(P=.028). The level of changes of self care behavior was related to age(P=.049), that of dosalis pedis blood flow was significant difference according to smoking(P=.042), that of skin temperatureof foot(P=.002) and dosalis pedis pulse(P=.038) were significant difference according to weight. The level of changes of capillary filling time of foot was related to diagnosis period(P=.014). Conclusion: Foot-Reflexo-Massage education program is an effective nursing intervention to promote foot care in diabetic patients. And the related factors can be recommended for the management of diabetic patients.

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Full waveform inversion by objective functions with power and integral (지수 및 적분을 포함한 목적함수에 의한 파형역산)

  • Ha, Wan-Soo;Pyun, Suk-Joon;Shin, Chang-Soo
    • 한국지구물리탐사학회:학술대회논문집
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    • 2007.06a
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    • pp.130-134
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    • 2007
  • Classical full waveform inversion for velocity estimation defines the objective function as the $l^2$ -norm of differences between the modeled and the observed wavefields. Although widely used, the results of this method have been less than satisfactory. A moderate improvement of this method is to define the objective function as the $l^2$ -norm of differences between the logarithms of the modeled and observed wavefields. In this paper we propose new objective functions of waveform inversion. They produce better results in sub-salt imaging than those of the classical and the logarithmic objective functions. One objective function defines the residual as the difference between $L^{th}$ power of the modeled wavefields and that of the observed wavefields. Another defines the residual as the difference between the integral of the $L^{th}$ power of the modeled wavefields and that of the observed wavefields. We apply these new objective functions to the synthetic SEG/EAGE salt model, and show that our new waveform inversion algorithms provide more accurate results than those of the classical and logarithmic waveform inversion methods.

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Differences of Foot Plantar Pressure Balance and Lung Capacity According to Change of Cervical Posture in Adults (경추 자세변화에 따른 성인의 족저압력 균형 및 폐활량의 차이)

  • Joo, Ha Young;Yang, Jeong Ok;Lee, Joong Sook
    • Korean Journal of Applied Biomechanics
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    • v.30 no.1
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    • pp.93-101
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    • 2020
  • Objective: The purpose of this study was to differences of foot plantar pressure balance and lung capacity according to cervical posture in adults. Method: The subjects consisted of 33 adults in their 20s and 50s who use M centers in B-gu and H-gu, B-City, and they measured foot plantar pressure balance and lung capacity according to cervical posture (cervical normal curvature posture, cervical flexural posture) in adults. Results: In this study, the difference of foot plantar pressure balance according to cervical posture were analyzed. In the difference between left and right foot pressure balance. It was 1.50% increased in the cervical flexural posture than in the cervical normal curvature posture, and a statistically significant difference was observed. In the difference between the anterior and posterior foot pressure balance. It was 4.28% increased in the cervical flexural posture than in the cervical normal curvature posture, and a statistically significant difference was observed. The difference of lung capacity according to cervical posture were analyzed. In the PEF, It was 58.63 l/min decreased in the cervical flexural posture than in the cervical normal curvature posture, and a statistically significant difference was observed. In the FEV1, It was 0.15 ℓ decreased in the cervical flexural posture than in the cervical normal curvature posture, and a statistically significant difference was observed. Conclusion: The results of this study suggest that had a positive effect on differences of foot plantar pressure balance and lung capacity at cervical normal curvature posture in adults. In future research, itis believed that research on the elderly who have collapsed the normal curvature posture due to aging, as well as teenagers whose normal curvature posture due to the use of smartphones, will contribute to the balance of foot pressure and improvement of the right cervical habits. In future studies, it is also believed that it will be necessary to measure lung capacity after performing exercise according to the cervical posture, thereby providing sufficient oxygen during exercise to enhance the persistence and efficiency of the movement.

A Study of Nonlinear Color Conversion by Neural Networks (신경망을 이용한 비선형 색 변환에 관한 연구)

  • 김석철
    • Journal of the Korean Graphic Arts Communication Society
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    • v.14 no.2
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    • pp.115-128
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    • 1996
  • In this paper, we describe the Color Correction and Preferred Skin Color Reproduction in a ink-jet color printer. The fundamental color correction that converts RGB densities into GMY densities has been ordinarily used. This method can reduce the hue error, but color difference between the preferred skin colors and hardcopy skin colors are large. We have been able to reduce color differences between original skin color and hardcopy skin color by transforming hardcopy skin colors` coordinates into Preferred Skin Colors` coordinates. Experimental results show that the described method is useful and valid for the skin color reproduction in a digital color printer.

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Development of Optimized Compact Finite Difference Schemes (최적화된 집적 유한 차분법을 위한 내재적 시간전진 기법의 개발)

  • Park N. S.;Kim J. W.;Lee D. J.
    • 한국전산유체공학회:학술대회논문집
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    • 1998.11a
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    • pp.7-12
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    • 1998
  • Optimized high-order compact(OHOC) schemes were proposed, which have high spatial order of truncation and resolution to simulate the aeroacoustic problems due to unsteady compressible flows. Generally, numerical schemes are categorized explicit or implicit by time-marching method. In this research, OHOC differences which were developed with explicit time-marching method is used to have implicit formulation and the implicit OHOC differences result in block hepta-diagonal matrix. This paper presents the comparisons between the explicit and implicit OHOC schemes with a second order accuracy of time in the 1-d linear wave convection problem, and between the explicit OHOC scheme of 4th-order accuracy in time and the implicit OHOC scheme of 1st-order accuracy in tine for the 1-d nonlinear wave convection problem. With these comparisons, the characteristics of implicit OHOC scheme are shown in the point of CFL number.

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Hybrid Anti-aliasing Method for 3D Object represented by Point Sampling (포인트 샘플링으로 표현된 3차원 객체를 위한 하이브리드 앤티앨리어싱 방법)

  • Kim, Hak-Ran;Park, Hwa-Jin
    • Journal of Digital Contents Society
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    • v.8 no.1
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    • pp.85-91
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    • 2007
  • This paper proposes a new hybrid anti-aliasing method for reducing aliasing appearing on an implicit surface using the point sampling. The hybrid anti-aliasing method is a method that finds differences in the values of pixel shown in Z-buffers for an implicit surface and thereby uses each of three types of Z-buffer. After determining the level of differences, it expresses a 3 dimensional object by using a multi Z-buffer if the level is severe, a double Z-buffer for a middle level, and only the original Z-buffer for a negligible difference. In comparison with the existing method in which multi Z-buffers have been entirely used for enhancing the anti-aliasing effect, the hybrid anti-aliasing method is an efficient method demonstrating an effect similar to the one using a multi Z-buffer while reducing the number of Z-buffers to be used.

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Impacts of Health Insurance Coverage Expansion on Health Care Utilization and Health Status (건강보험 보장성 확대가 의료이용 및 건강수준에 미치는 영향)

  • Bae, Ji-Young
    • Korean Journal of Social Welfare Studies
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    • v.41 no.2
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    • pp.35-65
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    • 2010
  • The purpose of this study is to identify the relationship between health insurance and health by evaluating the impacts of health insurance coverage expansion on health care utilization and health status. To analyze the causal relationship between health insurance and health, this study employed a "difference-in-difference method" that could compare changes in health care utilization and health status across groups in health insurance coverage expansion in 2005. The researcher predicted that the expansion of health insurance coverage would be an exogenous source of variation in the prices of health service use. First, the difference-in-differences estimator between 'illness group' and 'non-illness group' revealed that the increase in coverage of inpatient care services would result from the increases in the stay of length of 'non-illness group' rather than that of 'illness group'. However, the difference-in-differences estimator between 'serious illness group' and 'chronic illness group' identified that the policy change that focuses on expansion of the coverage for 'serious illness' effects on the increases in health care utilization and promotion of health status. In summary, the changes of health insurance coverage focusing on serious illness and inpatient care have positive effects on health care utilization and health status of serious illness group. But, 'non-illness groups' with acute illness receive more benefits from the policy change than 'illness group' with chronic illness.