• Title/Summary/Keyword: reference parameter

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Compressive Creep Behavior of Rice Starch Gels (쌀 전분 젤의 creep 특성)

  • Hong, Seok-In;Kim, Young-Sug;Choi, Dong-Won;Pyun, Yu-Ryang
    • Korean Journal of Food Science and Technology
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    • v.24 no.2
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    • pp.165-170
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    • 1992
  • The creep behavior of gels made with $30{\sim}45%$ gelatinized rice starch was measured over a wide range of temperature. Compressive creep curves of rice starch gels conformed to a six element mechanical model consisting of one Hookean, two Voigt and one Newtonian component. The creep compliance of gels decreased with increasing starch concentrations. Among viscoelastic constants of the mechanical model, elastic modulus was mainly influenced by the change of starch concentrations. The concentration-invariant compliance curve was obtained by reduction to 38% using reduction parameter $a_{c}$. The creep compliance curves of 45% starch gels increased with temperature, which indicated that rice starch gels became softer and less rigid with increasing temperature. When the compliance at $20^{\circ}C$ was set as a reference curve, creep compliance data for 45% gels at various temperature could be superimposed as a continuous smooth curve. The apparent activation energies of 45% rice starch gels calculated by the modified WLF equation were not intrinsic, but decreased as temperature increased.

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A Structural Model for Health Promotion and Life Satisfaction of Life in College Students in Korea (대학생들의 건강증진행위와 삶의 만족도에 대한 구조모형)

  • Hong, Youn-Lan;Yi, Ga-Eon;Park, Hyun-Sook
    • Research in Community and Public Health Nursing
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    • v.11 no.2
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    • pp.333-346
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    • 2000
  • The purpose of this study was designed to test and develope the structural model that explains health promoting behaviors among college students in Korea. The hypothetical model was constructed on the Pender's Health promotion Model(l996) and the inclusion of some influential factors for life satisfaction. The conceptual framework was built around eight constructs. Exogenous variables included in the model were self-esteem, perceived health status, self-efficacy, internal locus of control, chance locus of control. powerful other locus of control. Endogenous variables were health promotion behaviors and life satisfaction. The results are as follows; 1. The overall fit of the hypothetical model to the data was moderate <$x^2$=4.18(df=11. p=0.041), GFI= 0.99, AGFI= 0.76, RMR= 0.019, CFI= 0.99, CN= 248.50> 2. Path and variable of the model were modified by considering both its theoretical implication and statistical significance of parameter estimates. Compared to the hypothetical model. the revised model has become parsimonious and had a better fit to the data expected in a chi-square value <$x^2$=8.43( df= 16, p=0.21), GFI= 0.99, AGFI= 0.92., RMR= 0.024, CFI= 0.99, CN= 312.01> 3. Some of the predictive factors. especially self efficacy. self esteem. powerful others locus of control. perceived health status revealed the direct effects on health promoting behaviors. Of these variables. self-efficacy was the most signigicant factor. These predictive variables of health promoting behaviors explained 59% of total variances in the model. 4. Health promoting behaviors, self-esteem. and perceived health status revealed direct effect on the life satisfaction. Self-efficacy was identified as an important variable that contributed indirectly to improve life satisfaction by enhancing health promoting behaviors. These predictive variables of life satisfaction explained 42% of total variances in the model. In conclusion. the derived model in this study is considered appropriate in explaining and predicting health promoting models and life satisfaction among college students in Korea and could effectively be used as a reference model for further studies by suggesting a direction in health promoting nursing practices.

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Development of an EEG Software for Two-Channel Cerebral Function Monitoring System (2채널 뇌기능 감시 시스템을 위한 뇌파 소프트웨어의 개발)

  • Kim, Dong-Jun;Yu, Seon-Guk;Kim, Seon-Ho
    • Journal of Biomedical Engineering Research
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    • v.20 no.1
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    • pp.81-90
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    • 1999
  • This paper describes an EEG(electroencephalogram) software for two-channel cerebral function monitoring system to detect the cerebral ischemia. In the software, two-channel bipolar analog EEG signals are digitized and from the signals various EEG parameters are extracted and displayed on a monitor in real-time. Digitized EEG signal is transformed by FFT(Fast Fourier transform) and represented as CSA(compressed spectral array) and DSA(density spectral array). Additional 5 parameters, such as alpha ratio, percent delta, spectral edge frequency, total power, and difference in total power, are estimated using the FFT spectra. All of these are effectively merged in a monitor and displayed in real-time. Through animal experiments and clinical trials on men, the software is modified and enhanced. Since the software provides raw EEG, CSA, DSA, simultaneously with additional 5 parameters in a monitor, it is possible to observe patients multilaterally. For easy comparison of patient's status, reference patterns of CSA, DSA can be captured and displayed on top of the monitor. And user can mark events of surgical operation and patient's conditions on the software, this allow him jump to the points of events directly, when reviewing the recorded EEG file afterwards. Other functions, such as forward/backward jump, gain control, file management are equipped and these are operated by simple mouse click. Clinical tests in a university hospital show that the software responds accurately according to the conditions of patients and medical doctors can use the software easily.

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A comparison and prediction of total fertility rate using parametric, non-parametric, and Bayesian model (모수, 비모수, 베이지안 출산율 모형을 활용한 합계출산율 예측과 비교)

  • Oh, Jinho
    • The Korean Journal of Applied Statistics
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    • v.31 no.6
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    • pp.677-692
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    • 2018
  • The total fertility rate of Korea was 1.05 in 2017, showing a return to the 1.08 level in the year 2005. 1.05 is a very low fertility level that is far from replacement level fertility or safety zone 1.5. The number may indicate a low fertility trap. It is therefore important to predict fertility than at any other time. In the meantime, we have predicted the age-specific fertility rate and total fertility rate by various statistical methods. When the data trend is disconnected or fluctuating, it applied a nonparametric method applying the smoothness and weight. In addition, the Bayesian method of using the pre-distribution of fertility rates in advanced countries with reference to the three-stage transition phenomenon have been applied. This paper examines which method is reasonable in terms of precision and feasibility by applying estimation, forecasting, and comparing the results of the recent variability of the Korean fertility rate with parametric, non-parametric and Bayesian methods. The results of the analysis showed that the total fertility rate was in the order of KOSTAT's total fertility rate, Bayesian, parametric and non-parametric method outcomes. Given the level of TFR 1.05 in 2017, the predicted total fertility rate derived from the parametric and nonparametric models is most reasonable. In addition, if a fertility rate data is highly complete and a quality is good, the parametric model approach is superior to other methods in terms of parameter estimation, calculation efficiency and goodness-of-fit.

The Effects of Depression, Death Anxiety, and Social Support on Psychological Well-Being of Elderly Living Alone: Mediating Effect of Resilience (우울, 죽음불안, 사회적 지지가 독거노인의 심리적 안녕감에 미치는 영향: 탄력성의 매개효과)

  • Jang, Yeon-Sik;Mo, Seon-Hee
    • 한국노년학
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    • v.37 no.3
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    • pp.527-547
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    • 2017
  • The purpose of this study is to investigate how depression, death anxiety, and social support can exert influence on the psychological well-being of elderly living alone through a parameter of resilience. A survey was conducted involving 988 elderly over the age of 65 living alone in the Daejeon metropolitan area and Chungcheongnam-do and the data were analyzed using structure equation model. The results were as follows. First, in the measurement of variables according to demographic characteristics, depression showed significant differences depending on gender, level of education, health, and financial condition, while death anxiety differed depending on gender, and level of education. Social support was significantly different by gender, age, level of education, region, health, and financial condition. The level of resilience was significantly different by gender, age, level of education, health, and financial condition. Psychological well-being varied according to gender, level of education, health, and financial condition. Second, the effects of depression, death anxiety and social support on psychological well-being were examined. It was found that depression had a negative influence and social support had a positive impact while death anxiety showed no influence. Third, with regard to the effects of depression, death anxiety, social support on resilience, depression was found having negative influence, whereas social support having positive influence. Forth, psychological well-being was positively affected by resilience. Also, through the mediated pathway of resilience, their psychological well-being seemed to totally improve when the negative factors were reduced and the positive ones promoted. This study may have some significance in reference to examine the factors affecting the psychological well-being of elderly living alone and to develop social welfare service programs and policies in the field.

A ScanSAR Processing without Azimuth Stitching by Time-domain Cross-correlation (Azimuth Stitching 없는 ScanSAR 영상화: 시간영역 교차상관)

  • Won, Joong-Sun
    • Korean Journal of Remote Sensing
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    • v.38 no.3
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    • pp.251-263
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    • 2022
  • This paper presents an idea of ScanSAR image formation. For image formation of ScanSAR that utilizes the burst mode for raw signal acquisition, most conventional single burst methods essentially require a step of azimuth stitching which contributes to radiometric and phase distortions to some extent. Time-domain cross correlation could replace SPECAN which is most popularly used for ScanSAR processing. The core idea of the proposed method is that it is possible to relieve the necessity of azimuth stitching by an extension of Doppler bandwidth of the reference function to the burst cycle period. Performance of the proposed method was evaluated by applying it to the raw signals acquired by a spaceborne SAR system, and results satisfied all image quality requirements including 3 dB width, peak-to-sidelobe ratio (PSLR), compression ratio,speckle noise, etc. Image quality of ScanSAR is inferior to that of Stripmap in all aspects. However, it is also possible to improve the quality of ScanSAR image competitive to that of Stripmap if focused on a certain parameter while reduced qualities of other parameters. Thus, it is necessary for a ScanSAR processor to offer a great degree of flexibility complying with different requirements for different applications and techniques.

The effect of experience factors of untact fashion·beauty performances on customer satisfaction through perceived value (비대면 패션·뷰티 공연의 체험요인이 지각된 가치를 매개로 고객만족에 미치는 영향)

  • Lee, Jihyo;Na, Jin-eok;Kim, Kenneth Chi Ho
    • Journal of Digital Convergence
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    • v.19 no.5
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    • pp.383-395
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    • 2021
  • The purpose of this study is based on Pine and Gilmore's (1998) Experiential Economic Theory (4E's). This study mediates the perceived value of the experience factors (entertainment, aesthetic, deviant and educational experience) of Untact fashion and beauty performances. The impact on customer satisfaction was analyzed a total of 230 questionnaires were collected for visitors to the 15th Untact 'Asia Model Festival', which were successfully held in Seoul in 2020. The statistical analysis method used the SPSS 21.0 statistical program. As a result of the study, it was found that the experience factors had a significant effect on perceived value and customer satisfaction. In addition, perceived value was found to have a significant effect on customer satisfaction, and perceived value as a parameter was found to partially mediate the effect of experience factors on customer satisfaction. By studying the empirical analysis in this way, practical implications were presented and basic data that could be used for reference to related research were provided. However, future research should contribute to academic development through research on variables not covered in this research, and research on various untact performances should be continued.

Underwater acoustic communication performance in reverberant water tank (잔향음 우세 수조 환경에서의 수중음향 통신성능 분석)

  • Choi, Kang-Hoon;Hwang, In-Seong;Lee, Sangkug;Choi, Jee Woong
    • The Journal of the Acoustical Society of Korea
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    • v.41 no.2
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    • pp.184-191
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    • 2022
  • Underwater acoustic wave in shallow water is propagated through multipath that has a large delay spread causing Inter-Symbol Interference (ISI) and these characteristics deteriorate the performance in the communication system. In order to analyze the communication performance and investigate the correlation with multipath delay spread in a reverberant environment, an underwater acoustic communication experiment using Binary Phase-Shift Keying (BPSK) signals with symbol rates from 100 sym/s to 8000 sym/s was conducted in a 5 × 5 × 5 m3 water tank. The acoustic channels in a well-controlled tank environment had the characteristics of dense multipath delay spread due to multiple reflections from the interfaces and walls within the tank and showed the maximum excess delay of 40 ms or less, and the Root Mean Squared (RMS) delay spread of 8 ms or less. In this paper, the performances of Bit Error Rate (BER) and output Signal-to-Noise Ratio (SNR) were analyzed using four types of communication demodulation techniques. And the parameter, Symbol interval to Delay spread Ratio in reverberant environment (SDRrev), which is the ratio of symbol interval to RMS delay spread in the reverberant environment is defined. Finally, the SDRrev was compared to the BER and the output SNR. The results present the reference symbol rate in which high communication performance can be guaranteed.

Genetic diversity and population structure in five Inner Mongolia cashmere goat populations using whole-genome genotyping

  • Tao Zhang;Zhiying Wang;Yaming Li;Bohan Zhou;Yifan Liu;Jinquan Li;Ruijun Wang;Qi Lv;Chun Li;Yanjun Zhang;Rui Su
    • Animal Bioscience
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    • v.37 no.7
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    • pp.1168-1176
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    • 2024
  • Objective: As a charismatic species, cashmere goats have rich genetic resources. In the Inner Mongolia Autonomous Region, there are three cashmere goat varieties named and approved by the state. These goats are renowned for their high cashmere production and superior cashmere quality. Therefore, it is vitally important to protect their genetic resources as they will serve as breeding material for developing new varieties in the future. Methods: Three breeds including Inner Mongolia cashmere goats (IMCG), Hanshan White cashmere goats (HS), and Ujimqin white cashmere goats (WZMQ) were studied. IMCG were of three types: Aerbas (AEBS), Erlangshan (ELS), and Alashan (ALS). Nine DNA samples were collected for each population, and they were genomically re-sequenced to obtain high-depth data. The genetic diversity parameters of each population were estimated to determine selection intensity. Principal component analysis, phylogenetic tree construction and genetic differentiation parameter estimation were performed to determine genetic relationships among populations. Results: Samples from the 45 individuals from the five goat populations were sequenced, and 30,601,671 raw single nucleotide polymorphisms (SNPs) obtained. Then, variant calling was conducted using the reference genome, and 17,214,526 SNPs were retained after quality control. Individual sequencing depth of individuals ranged from 21.13× to 46.18×, with an average of 28.5×. In the AEBS, locus polymorphism (79.28) and expected heterozygosity (0.2554) proportions were the lowest, and the homologous consistency ratio (0.1021) and average inbreeding coefficient (0.1348) were the highest, indicating that this population had strong selection intensity. Conversely, ALS and WZMQ selection intensity was relatively low. Genetic distance between HS and the other four populations was relatively high, and genetic exchange existed among the other four populations. Conclusion: The Inner Mongolia cashmere goat (AEBS type) population has a relatively high selection intensity and a low genetic diversity. The IMCG (ALS type) and WZMQ populations had relatively low selection intensity and high genetic diversity. The genetic distance between HS and the other four populations was relatively high, with a moderate degree of differentiation. Overall, these genetic variations provide a solid foundation for resource identification of Inner Mongolia Autonomous Region cashmere goats in the future.

Evaluation for Optimization of CT Dose Reduction Methods in PET/CT (PET/CT 검사 시 CT 피폭선량 감소 방법들의 최적화 평가)

  • Do, Yong Ho;Lee, Hong Jae;Kim, Jin Eui
    • The Korean Journal of Nuclear Medicine Technology
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    • v.19 no.2
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    • pp.55-62
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    • 2015
  • Purpose Various methods for reducing radiation exposure have been continuously being developed. The aim of this study is to evaluate effectiveness of dose reduction, image quality and PET SUV changes by applying combination of automatic exposure dose(AEC), automated dose-optimized selection of X-ray tube voltage(CAREkV) and sinogram affirmed iterative reconstruction(SAFIRE) which can be controled by user. Materials and Methods Torso, AAPM CT performance and IEC body phantom images were acquired using biograph mCT64, (Siemens, Germany) PET/CT scanner. Standard CT condition was 120 kV, 40 mAs. Radiation exposure and noise were evaluated by applying AEC, CAREkV(120 kV, 40 mAs) and SAFIRE(120 kV, 25 mAs) with torso phantom compare to standard CT condition. And torso, AAPM and IEC phantom images were acquired with combination of 3 methods in condition of 120 kV, 25 mAs to evaluate radiation exposure, noise, spatial resolution and SUV changes. Results When applying AEC, CTDIvol and DLP were decreased by 50.52% and 50.62% compare to images which is not applying AEC. mAs was increased by 61.5% to compensate image quality according to decreasing 20 kV when applying CAREkV. However, CTDIvol and DLP were decreased by 6.2% and 5.5%. When reference mAs was the lower and strength was the higher, reduction of radiation exposure rate was the bigger. Mean SD and DLP were decreased by 2.2% and 38% when applying SAFIRE even though mAs was decreased by 37.5%(from 40 mAs to 25 mAs). Combination of 3 methods test, SD decreased by 5.17% and there was no significant differences in spatial resolution. And mean SD and DLP were decreased by 6.7% and 36.9% compare to 120 kV, 40 mAs with AEC. For SUV test, there was no statistical differences(P>0.05). Conclusion Combination of 3 methods shows dose reduction effect without degrading image quality and SUV changes. To reduce radiation exposure in PET/CT study, continuous effort is needed by optimizing various dose reduction methods.

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