• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.1
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• pp.31-36
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• 2009

This study was conducted to find out an alternative way of rapid and accurate analysis of forage quality. Near reflectance infrared spectroscopy (NIRS) was used to evaluate the possibility of forage analysis and collect 258 samples such as barley for whole crop silage, forage corn and sudangrass from 2002 to 2007. The samples were analyzed for CP (crude protein), CF (crude fiber), ADF (acid detergent fiber), NDF (neutral detergent fiber) and IVTD (in vitro true digestibility), and also scanned using NIRSystem with wavelength from $400{\sim}2,400nm$. Multiple linear regression was used with wet analysis data for developing the calibration model and validate unknown samples. The important index In this experiment was SEC and SEP $r^2$ for CF, CP, NDF, ADF and IVTD in calibration set were 0.70, 0.86, 0.94, 0.94 and 0.89, also 0.47, 0.39, 0.89, 0.90 and 0.61 in validation sample, respectively. The results of this experiment indicates that NIRS was reliable analytical method to assess forage quality, specially in CF, ADF and IVTD, sample should be included for respective forage samples to get accurate result. More robust calibrations can be made to cover every forage samples if added representative sample set.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.5
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• pp.554-563
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• 2006

Numerous epidemiological studies have shown stronger associations between $PM_{2.5}$ and both mortality and morbidity than $PM_{10}$. The association of $PM_{2.5}$ with respiratory mortality was examined in Seoul, during the period of $1996{\sim}2002$. Because $PM_{2.5}$ data were available for only 10% of this time period, a prediction regression model was developed to estimate $PM_{2.5}$ concentration. Death count due to respiratory-related diseases(total respiratory mortality; ICD-10, J00-J98) and death counts(cause-specific mortality) due to pneumonia(ICD-10, J12-J18), COPD(ICD-10, J40-J44) and asthma(ICD-10, J45-J46) were considered in this study. Averaged daily mortality was 5.6 for total respiratory mortality and 1.1 to 1.6 for cause-specific mortality. Generalized additive Poisson models controlling for confounders were used to evaluate the acute effects of particle exposures on total respiratory mortality and cause-specific mortality. An IQR increase in 5-day moving average of $PM_{2.5}(22.6{\mu}g/m^3)$ was associated with an 8.2%(95% CI: 4.5 to 12.1%) increase in total respiratory mortality The association of $PM_{2.5}$ was stronger for the elderly ($\geq$65 years old, 10.1%, 95% CI: 5.8 to 14.5%) and for males(8.9%, 95% CI: 2.1 to 11.3%). A $10{\mu}g/m^3$ increase in 5-day moving average of $PM_{2.5}$ was strongly associated with total respiratory mortality in winter(9.5%, 95% CI: 6.6 to 12.4%), followed by spring(3.1%, 95% CI: -1.2 to 7.5%), which was a different pattern with the finding in North American cities. However, our results are generally consistent with those observed in recent epidemiological studies, and suggest that $PM_{2.5}$ has a stronger effect on respiratory mortality in Seoul.

• Journal of the Korean GEO-environmental Society
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• v.9 no.5
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• pp.45-52
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• 2008

The present study has extended OpenSees, which is an open-source software framework DOS program for developing applications to idealize geotechnical and structural problems, for the static analysis of axial load capacity and settlement of single piles in MS Windows environment. The Windows version of OpenSees as improved by this study has enhanced the DOS version from a general purpose software program to a special purpose program for driven and bored pile analysis with additional features of pre-processing and post-processing and a user friendly graphical interface. The method used in the load capacity analysis is the numerical methods based on load transfer functions combined with finite elements. The use of empirical nonlinear T-z and Q-z load transfer curves to model soil-pile interaction in skin friction and end bearing, respectively, has been shown to capture the nonlinear soil-pile response under settlement due to load. Validation studies have shown the static load capacity and settlement predictions implemented in this study are in fair agreement with reference data from the static loading tests.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.7
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• pp.967-972
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• 2017

Objective: Two experiments were conducted to determine the effects of forage-to-concentrate (F:C) ratio on the nutrient digestibility and enteric methane ($CH_4$) emission in growing goats and Sika deer. Methods: Three male growing goats (body weight $[BW]=19.0{\pm}0.7kg$) and three male growing deer ($BW=19.3{\pm}1.2kg$) were respectively allotted to a $3{\times}3$ Latin square design with an adaptation period of 7 d and a data collection period of 3 d. Respiration-metabolism chambers were used for measuring the enteric $CH_4$ emission. Treatments of low (25:75), moderate (50:50), and high (73:27) F:C ratios were given to both goats and Sika deer. Results: Dry matter (DM) and organic matter (OM) digestibility decreased linearly with increasing F:C ratio in both goats and Sika deer. In both goats and Sika deer, the $CH_4$ emissions expressed as g/d, g/kg $BW^{0.75}$, % of gross energy intake, g/kg DM intake (DMI), and g/kg OM intake (OMI) decreased linearly as the F:C ratio increased, however, the $CH_4$ emissions expressed as g/kg digested DMI and OMI were not affected by the F:C ratio. Eight equations were derived for predicting the enteric $CH_4$ emission from goats and Sika deer. For goat, equation 1 was found to be of the highest accuracy: $CH_4(g/d)=3.36+4.71{\times}DMI(kg/d)-0.0036{\times}neutral$ detergent fiber concentrate (NDFC,g/kg)+$0.01563{\times}dry$ matter digestibility (DMD,g/kg)-$0.0108{\times}neutral$ detergent fiber digestibility (NDFD, g/kg). For Sika deer, equation 5 was found to be of the highest accuracy: $CH_4(g/d)=66.3+27.7{\times}DMI(kg/d)-5.91{\times}NDFC(g/kg)-7.11{\times}DMD(g/kg)+0.0809{\times}NDFD(g/kg)$. Conclusion: Digested nutrient intake could be considered when determining the $CH_4$ generation factor in goats and Sika deer. Finally, the enteric $CH_4$ prediction model for goats and Sika deer were estimated.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.5
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• pp.371-380
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• 2017

The risk-targeted seismic design concept was first included in ASCE/SEI 7-10 to address problems related to the uniform-hazard based seismic concept that has been constructed without explicitly considering probabilistic uncertainties in the collapse capacities of structures. However, this concept is not yet reflected to the current Korean building code(KBC) because of insufficient strong earthquake data occurred at the Korean peninsula and little information on the collapse capacities of structures. This study evaluates the risk-targeted seismic performance of steel ordinary concentrically braced frames(OCBFs). To do this, the collapse capacities of prototype steel OCBFs are assessed with various analysis parameters including building locations, building heights and soil conditions. The seismic hazard curves are developed using an empirical spectral shape prediction model that is capable of reflecting the characteristics of earthquake records. The collapse probabilities of the prototype steel OCBFs located at the Korean major cities are then evaluated using the risk integral concept. As a result, analysis parameters considerably influence the collapse probabilities of steel OCBFs. The collapse probabilities of taller steel OCBFs exceed the target seismic risk of 1 percent in 50 years, which the introduction of the height limitation of steel OCBFs into the future KBC should be considered.

• Nuclear Engineering and Technology
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• v.4 no.4
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• pp.306-321
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• 1972

Molecular reorientation in (NH$_4$)$_2$SO$_4$, has been studied by cold neutron scattering. For T=300$^{\circ}$K data, the isolated quasielastic spectra and form-factors at various scattering angles are compared with four reorientational models based on SKOLD theory. Front these, it is concluded that the NH$_4$ions are performing either 3-fold four axes or 2-fold three axes reorientation with $\tau$$_{c}$=2.0$\times$10$^{-11}$ sec. The temperature dependence of f. is studied over 100$^{\circ}$K-413$^{\circ}$K and for the high-temperature phase, the widths of composite spectra are compared with the results from NMR relaxation measurements. All the results have shown that the neutron scattering method is capable of giving detalis of the reorientational modes in solids and therefore some discussions are given on the application of this method. A study of the form-factor is applied for NH$_4$I (Phase I) by comparing the measurement with the calculation based on free rotation approximation and proposed a reorientation model of NH$_4$ ions in the octahedral potential cage with $\tau$$_{c}$$\leq$10$^{-12}$ sec. Also a brief theoretical prediction for the effect of reorientational motions on the inelastic spectrum is discussed.sed.

• Radiation Oncology Journal
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• v.36 no.2
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• pp.139-146
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• 2018

Purpose: IBTR! 2.0 nomogram is web-based nomogram that predicts ipsilateral breast tumor recurrence (IBTR). We aimed to validate the IBTR! 2.0 using an external data set. Materials and Methods: The cohort consisted of 2,206 patients, who received breast conserving surgery and radiation therapy from 1992 to 2012 at our institution, where wide surgical excision is been routinely performed. Discrimination and calibration were used for assessing model performance. Patients with predicted 10-year IBTR risk based on an IBTR! 2.0 nomogram score of <3%, 3%-5%, 5%-10%, and >10% were assigned to groups 1, 2, 3, and 4, respectively. We also plotted calibration values to observe the actual IBTR rate against the nomogram-derived 10-year IBTR probabilities. Results: The median follow-up period was 73 months (range, 6 to 277 months). The area under the receiver operating characteristic curve was 0.607, showing poor accordance between the estimated and observed recurrence rate. Calibration plot confirmed that the IBTR! 2.0 nomogram predicted the 10-year IBTR risk higher than the observed IBTR rates in all groups. High discrepancies between nomogram IBTR predictions and observed IBTR rates were observed in overall risk groups. Compared with the original development dataset, our patients had fewer high grade tumors, less margin positivity, and less lymphovascular invasion, and more use of modern systemic therapies. Conclusions: IBTR! 2.0 nomogram seems to have the moderate discriminative ability with a tendency to over-estimating risk rate. Continued efforts are needed to ensure external applicability of published nomograms by validating the program using an external patient population.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.23 no.2
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• pp.69-75
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• 2012

Objectives : The current study was conducted in order to investigate teachers' recognition of school bullying using a nationwide database of adolescents in middle and high school in Korea. Methods : Students in the 7th to 12th grades at 23 secondary schools participated in the current study during the fall of 2009. Subjects completed the self-report form of the Adolescent Mental Health and Problem Behavior Screening Questionnaire-II (AMPQ-II) and Symptom Checklist-90 Revised (SCL-90-R). In addition, relevant teachers used the teachers' rating scale of the AMPQ-II to report their students' status. Differences in the number of bullied students between teachers' recognition and students' report were explored. Results : A total of 2270 subjects provided relevant responses to the questionnaire. While the one-month prevalence of victimization according to students' self-reports was 28.9%, the recognized prevalence by teachers was only 10.6%. For prediction of the presence of school bullying according to students' self reports on the AMPQ-II, item 7 of the teachers' report on the AMPQ-II showed a sensitivity of 16%, a specificity of 92%, a positive predictability of 44%, a negative predictability of 72%, a false positive rate of 8%, a false negative rate of 84%, and an accuracy of 69%, respectively. No significant differences in subscores of students' self reports of the AMPQ-II and SCL-90-R were observed between bullied students who were recognized by teachers and those who were not recognized. In stepwise discriminant analysis, classification of teachers' item 2 and item 7 on the AMPQ-II with respect to school bullying according to students' reports showed an accuracy of 63.4%. Using this model, 75.2% of non-victimized subjects were classified correctly, while only 35.2% of victimized subjects were classified correctly. Conclusion : Despite the high prevalence in Korea, teachers' recognition of school violence among their students remains low. Pre-professional and continuing education to improve teachers' understanding of school bullying and knowledge of effective classroom-based prevention activities should be encouraged.

• Spatial Information Research
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• v.15 no.3
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• pp.267-278
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• 2007

Internationally many models are developed and applied to predict the impact of the climate change, as occurring a lot of symptoms by climate change. Also, in Korea, according to increasing the application of the climate effect model in many research fields, it is required to study the method for preparing climate data and the characteristics of the climate. In this study IDSW (Inverse Distance Squared Weighting), one of the spatial statistic methods, is applied to interpolate. This method estimates a point of interest by assigning more weight to closer points, which are limited to be select by 3 in 100 km radius. As a result, annual average temperature and precipitation had increased by $0.4^{\circ}C$ and 412 mm during 1977 to 2006. They are also predicted to increase by $3.96^{\circ}C$, 319 mm in the 2100 compared to 2007. High variability of temperature and precipitation for last 30 years shows in some part of the Gangwon-do and in the southern part of Korea. Besides in the study of the variable trend, the variability of temperature and precipitation is inclined to increase in Gangwon-do and southern east part, respectively. However, during 2071 to 2100 variability of temperature is predicted to be high in midwest of Korea and variability of precipitation in the east. In the trend of variability, variability of temperature is apt to increase into west south, and variability of precipitation increase in midwest and a part of south.

• Journal of Digital Contents Society
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• v.15 no.1
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• pp.19-27
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• 2014

In order to estimate the life of 2,5 inch HDD which is adopted by PC environment, make the test plan which reflect the failure mode of market, make the test model of accelerated life test which reflect the stress of temperature. after an analysis of the environment of PC using, test procedure was decided that operation was write 50 % and read 50 %, and then access method was sequential 50 % and random 50%. The acceleration life test was executed on condition that temperature was $50^{\circ}C$ and $60^{\circ}C$, performance was 95 % in max performance, test time was 1000 hours. by the test of goodness of fit of anderson-darling of the failure data during test, it was confirmed that the distribution of failure fellow weibull. test for shape and scale was equal, and shape parameter was 0.7177, characteristic life was 429434 hours at normal user condition($30^{\circ}C$) by the analysis of weibull-arrhenius modeling. It made no difference about the statistics when equality test was executed. The activation energy was 0.2775eV. In analyzing between the failure samples of acceleration test and the samples of market return even though there is detail difference about the share of failure mode, the rank of share was almost same. This study suggest the test procedure of acceleration test of 2.5 inch HDD in PC using environment, and help the life estimation at manufacture and user.