• Journal of agriculture & life science
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• v.45 no.5
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• pp.127-143
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• 2011

Assessment of APC has focused on large size, specialization, and structuralization based on business performance. In the future, first, it should be complemented to have correlation with management efficiency. Second, because of the rate of weight for each index, it is necessary to develop a specific index or adjust allotting of marks so that there can be correlation between indexes. Third, since APCs have high values in the composite assessment and low values in the sales amount, it is necessary to develop various kinds of indexes, including the index to evaluate processing value-added, that of customer satisfaction with assessment, and that of customer relationship maintenance performance through introduction of a customer relationship management system (CRM), in pursuit of balance. Lastly, the results of this study are expected to be able to help make APCs efficient in relation to integration of production organizations so that they will convert and develop into a basic product processing center in coping with changes in internal and external environment of agricultural marketing.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.1
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• pp.1-6
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• 2010

The objectives of this study were to i) investigate genetic performance for linear type traits of individual Holstein dairy cows, especially focusing on comparative traits, and to estimate genetic variances for these traits using actual data, and ii) compare genetic performance and improvement of progeny by birth country of the cows. Linear type traits defined with five comparative traits on this study were general stature composite (GSC), dairy capacity composite (DCC), body size composite (BSC), foot and leg composite (FLC), and udder composite (UDC). These traits were scored from 1 to 6 with 1 = poor, 2 = fair, 3 = good, 4 = good plus, 5 = very good and 6 = excellent. Final scores (FS) were also included in this study. Data used was collected from the years 2000 to 2004 by the Korea Animal Improvement Association (KAIA). Only data of more than five tested cows by herd appraisal date and by sires having more than ten daughters were included to increase the reliability of the data analyses. A total of 30,204 records of the selected traits, which was collected from 26,701 individuals having pedigree information were used. Herd appraisal date, year of age, lactation stage (grouped by month), and time lagged for milking (in hours) were assumed as fixed effects on the model. Animal additive genetic effects considering pedigree relationship and residual errors were assumed with random effects. Year of age at appraisal date was classified from one to nine years of age, assigning the value of nine years of age for animals that were greater than or equal to nine years of age. From our results, the estimate for heritability was 0.463, 0.346, 0.473, 0.290, and 0.430 on GSC, DCC, BSC, FLC and UDC, respectively. The estimate for FS heritability was 0.539. The greatest breeding values for GSC were estimated for Canada, with the breeding values for American lines increasing for 10 years starting in 1989 but tending to decrease after that until 2004. For DCC, the breeding values for American and Canadian lines showed similar patterns until 1999, after which the breeding values for the American lines declined sharply. For BSC, data from Korea, Canada and the USA followed similar trends overall except when the breeding values of the American lines decreased starting in 1999. Overall, the methods used to evaluate genetic performance in this study were acceptable and allowed for the discovery of differences by country of genetic origin, likely due in part to the American use of selection indexes based primarily on milk yield traits until methods for evaluating other traits began to emerge.

• Journal of Korea Port Economic Association
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• v.33 no.3
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• pp.53-68
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• 2017

The purpose of this study is to develop a new Korean container freight index by applying weights based on the global trade volume. To achieve this, it was decided to determine the conditions such as establishment of routes and regions, weighting of trade volumes which based on prior research and expert advice. Based on this, the individual index and regional index and composite index were calculated, and then reliability and statistical significance of the index was verified through correlation analysis and Granger causality analyses. This study suggest the following findings, through the development of the Korean container freight index. Firstly, Korean freight index reflects the overall market situation and can be used as a benchmark for determining the conditions of each market, consisting of criteria of region and routes. Secondly, it is possible to reflect the market conditions in which actual freight differences exist, since it has developed separate indexes for export and import routes. Finally, The composite index is the only index that reflects not only exports and imports but also 27 individual routes based on Busan, which is the most comprehensive indicator of the korean container freight market.

• Journal of Environmental Health Sciences
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• v.44 no.5
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• pp.421-432
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• 2018

Objectives: In this study, we started to develop an indoor garden integrated IoT solution based on IAQ (indoor air quality) and interconnection with an environmental database for smart management of indoor gardens. The purpose of this study was to develop and apply an integrated solution for customized air purification from an indoor garden through big data analysis using IoT technology. Methods: An IoT-based IAQ monitoring system was established in three households within a new apartment building. Based on real-time and long-term data collected, $PM_{2.5}$, $CO_2$, temperature, and humidity changes were compared to those of indoor garden applications and the analyzed results were indexed. Results As a result of the installation, all three households had no results exceeding the standard for indoor air pollution on average $PM_{2.5}$ and $CO_2$ indices. In the case of indoor garden installation, the IAQ index increased to the "Good" section after the installation, and readings in the "Bad" section shown before the installation disappeared. The comfort index also did not dip into the "Uncomfortable" section, where it had been preinstallation, and significantly lowered the average score from "Uncomfortable for sensitive groups" to "Good". Overall, the IAQ composite index for the generation of installations decreased the "Good" interval, but "Bad" did not appear. Conclusions In this study on developing an integrated solution for IAQ based on IoT indoor gardens, big data was analyzed to determine IAQ and comfort indexes and an IAQ composite index. Through this process, it became understood that it is necessary to monitor IAQ based on IoT.

• Journal of Korean Academy of Nursing Administration
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• v.21 no.5
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• pp.542-551
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• 2015

Purpose: This study was done to evaluate validity and reliability of the Korean version of the expanded nursing stress scale (ENSS). Methods: Forward-backward translation of ENSS from English to Korean was conducted. The translated instrument was pilot-tested and administrated to 285 nurses who worked in five general hospitals in Korea. Internal consistency reliability was assessed using Cronbach's ${\alpha}$ and composite reliability. Validity was evaluated through construct validity with confirmatory factor analysis, convergent and discriminant validity. Results: The Korean version of ENSS showed a reliable internal consistency with Cronbach's ${\alpha}$ .95 and composite reliability .99. Model fit indexes for 46 items were validated by confirmatory factor analysis(goodness of fit index .82, Tucker-Lewis index .92, root mean square error of approximation .04), indicating suitable construct validity. Factor loading of the 48 items (.47~.88) and average variance extracted out of nine factors (.52~.71.) indicated satisfactory convergent validity. Some values of square of the correlation coefficient between factors (.12~.89) were higher than average variance extracted values of each factor (.52~.71) so that it partly satisfied discriminant validity. Conclusion: Findings show that the Korean version ENSS has good reliability and suitable validity; therefore, can be used to assess and identify Korean nurses' job stress.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.1
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• pp.1-12
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• 2021

In this paper, a new algorithm is proposed to estimate the damage location in the composite panel by extracting the elastic wave signal reflected from the damaged area. The guided elastic wave is generated by a piezoelectric actuator and sensed by a piezoelectric sensor. The proposed algorithm adopts a diagnostic approach. It compares the non-damaged signal with the damaged signal, and extract damage information along with sensor network and lamb wave group velocity estimated by signal correlation. However, it is difficult to clearly distinguish the damage location due to the nonlinear properties of lamb wave and complex information composed of various signals. To overcome this difficulty, the cumulative summation feature vector algorithm(CSFV) and a visualization technique are newly proposed in this paper. CSFV algorithm finds the center position of the damage by converting the signals reflected from the damage to the area of distance at which signals reach, and visualization technique is applied that expresses feature vectors by multiplying damage indexes. Experiments are performed for a composite panel and comparative study with the existing algorithms is carried out. From the results, it is confirmed that the damage location can be detected by the proposed algorithm with more reliable accuracy.

• The Korean Journal of Applied Statistics
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• v.23 no.4
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• pp.651-668
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• 2010

Various estimators of two risk measures of a specific financial portfolio, Value-at-Risk and Expected Shortfall, are compared for each case of 1-day and 10-day horizons. We use the Korea Composite Stock Price Index data of 20-year period including the year 2008 of the global financial crisis. Indexes of five foreign stock markets are also used for the empirical comparison study. The estimator considering both the heavy tail of loss distribution and the conditional heteroscedasticity of time series is of main concern, while other standard and new estimators are considered too. We investigate which estimator is best for the Korean stock market and which one shows the best overall performance.

• Steel and Composite Structures
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• v.26 no.4
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• pp.407-420
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• 2018

Experiments were performed to explore the hysteretic performance of steel reinforced concrete (SRC) cross-shaped columns. Nine specimens were designed and tested under the combined action of compression, flexure, shear and torsion. Torsion-bending ratio (i.e., 0, 0.14, 0.21) and steel forms (i.e., Solid - web steel, T - shaped steel, Channel steel) were considered in the test. Both failure processes and modes were obtained during the whole loading procedure. Based on experimental data, seismic indexes, such as bearing capacity, ductility and energy dissipation were investigated in detail. Experimental results suggest that depending on the torsion-bending ratio, failure modes of SRC cross-shaped columns are bending failure, flexure-torsion failure and torsion-shear failure. Shear - displacement hysteretic loops are fuller than torque - twist angle hysteretic curves. SRC cross-shaped columns exhibit good ductility and deformation capacity. In the range of test parameters, the existence of torque does not reduce the shear force but it reduces the displacement and bending energy dissipation capacity. What is more, the bending energy dissipation capacity increases with the rising of displacement level, while the torsion energy dissipation capacity decreases.

• Nutrition Research and Practice
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• v.5 no.2
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• pp.163-168
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• 2011

This study was conducted to evaluate recipients' perception of service quality, satisfaction, and behavioral intention in home delivered meals program in the US. Out of 398 questionnaires, 265 (66.6%) were collected, and 209 questionnaires (52.5%) were used for the statistical analysis. A Confirmatory Factor Analysis (CFA) with a maximum likelihood was first conducted to estimate the measurement model by verifying the underlying structure of constructs. The level of internal consistency in each construct was acceptable, with Cronbach's alpha estimates ranging from 0.7 to 0.94. All of the composite reliabilities of the constructs were over the cutoff value of 0.50, ensuring adequate internal consistency of multiple items for each construct. As a second step, a Meals-On-Wheels (MOW) recipient perception model was estimated. The model's fit as indicated by these indexes was satisfactory and path coefficients were analyzed. Two paths between (1) volunteer issues and behavioral intention and (2) responsiveness and behavioral intention were not significant. The path for predicting a positive relationship between food quality and satisfaction was supported. The results show that having high food quality may create recipient satisfaction. The findings suggest that food quality and responsiveness are significant predictors of positive satisfaction. Moreover, satisfied recipients have positive behavioral intention toward MOW programs.

• Steel and Composite Structures
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• v.26 no.6
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• pp.705-717
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• 2018

This paper presents a numerical investigation on the mechanical performance of concrete-filled dual steel tubular columns of circular section subjected to concentric axial load. A three-dimensional numerical model is developed and validated against a series of experimental tests. A good agreement is obtained between the experimental and numerical results, both in the peak load value and in the ascending and descending branches of the load-displacement curves. By means of the numerical model, a parametric study is carried out to investigate the influence of the main parameters that determine the axial capacity of double-tube columns, such as the member slenderness, inner and outer steel tube thicknesses and the concrete grade - of both the outer concrete ring and inner core -, including ultra-high strength concrete. A total number of 163 numerical simulations are carried out, by combining the different parameters. Specific indexes are defined (Strength Index, Concrete-Steel Contribution Ratio, Inner Concrete Contribution Ratio) to help rating the relative mechanical performance of dual steel tubular columns as compared to conventional concrete-filled steel tubular columns, and practical design recommendations are subsequently given.