• Journal of the Korean Geotechnical Society
• /
• v.30 no.1
• /
• pp.17-25
• /
• 2014

Offshore wind turbine foundations are subjected to wind, current and wave loadings. Hence, both static and cyclic behaviors of foundation's soil are important for the design of offshore wind turbine foundation. Undrained cyclic behaviors of soils depend upon the number of loading cycles, vertical effective stress, cyclic shear strain, relative density, and the combination of cyclic and average shear stresses. In order to evaluate the effect of average and cyclic shear stresses on the undrained cyclic behavior of marine silty sand, cyclic direct simple shear (CDSS) tests are performed with relative density of 85%, vertical effective stress of 200 and 300 kPa, and failure criteria of either 15% double amplitude cyclic shear strain (${\gamma}_{cyc}$) or permanent shear strain (${\gamma}_{p}$). The results are presented in the form of design graphs or contour diagrams. The undrained cyclic behavior of marine silty sand is found to be dependent on cyclic and average shear stresses and/or the combination of both shear stresses. It is found that when significant average shear stress exists the permanent or progressive shear strain is the govering failure criteria instead of cyclic shear strain.

• Asian-Australasian Journal of Animal Sciences
• /
• v.20 no.10
• /
• pp.1580-1586
• /
• 2007

The objective of this study was to compare the bioefficacy of L-lysine sulfate relative to L-lysine${\cdot}$HCl for 10 to 20 kg pigs. Two experiments were conducted to determine the bioefficacy of the two sources of lysine using daily gain, feed conversion, plasma urea nitrogen and nitrogen retention as the response criteria. In experiment 1, 168 crossbred barrows ($Landrace{\times}Large$ White), weaned at $28{\pm}3$ d ($9.07{\pm}0.78$kg body weight), were allotted to one of seven dietary treatments in a $2{\times}3$ (two lysine $sources{\times}three $ lysine levels) factorial arrangement of treatments with an added negative control treatment group. The basal diet was based on corn, peanut meal and soybean meal and provided 0.67% lysine. The basal diet was supplemented with 0.1, 0.2 or 0.3% lysine equivalents supplied from either L-lysine sulfate or L-lysine${\cdot}$HCl. Each treatment was fed to six pens of pigs with four pigs per pen. The trial lasted 21 days. The relative bioefficacy value of lysine in L-lysine sulfate using daily gain, feed conversion and plasma urea nitrogen as response criteria was 1.01, 1.05 and 1.04 of the lysine in L-lysine${\cdot}$HCl, respectively. In experiment 2, 42 crossbred ($Landrace{\times}Large$ White) pigs ($16.03{\pm}1.58$ kg body weight) were housed in stainless steel metabolism cages for 10 d and fed the seven diets used in the nitrogen-balance trial. The relative bioefficacy value of L-lysine sulfate was estimated to be 0.95 as effective as L-lysine${\cdot}$HCl for nitrogen retention on an equimolar basis. The t-test analysis revealed that bioefficacy of lysine in L-lysine sulfate was not significantly different from lysine in L-lysine${\cdot}$HCl, which was set at 1.00. In conclusion, L-lysine sulfate can be used instead of L-lysine${\cdot}$HCl to fortify lysine-deficient diets fed to 10 to 20 kg pigs.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.4
• /
• pp.471-478
• /
• 2020

This study aimed to suggest implications for the future development of agricultural R&D through a priority analysis of excellent agricultural R&D performance considering productivity, marketability, and effects on region, which are important factors of agricultural R&D evaluation. The subjects of analysis were R&D of Rural Development Administration (RDA), which was selected as national R&D excellent Performance from 2006 to 2018, and the priority was analyzed using Analytic Hierarchy Process (AHP). The results are as follows. First, the relative importance of the criteria decreased in the order of marketability(0.423) > regional impact(0.360) > productivity(0.216). Second, as a result of analyzing the relative importance of the sub-criteria, the possibility of commercialization(0.515) was high in the category of marketability. The possibility of technology expansion(0.538) was high in the category of effects on region and the quality improvement(0.464) was high in the category of productivity. Third, the excellent agricultural R&D performance that had high relative importance was the technologies associated with improving the agricultural competitiveness of horticultural crops.

• Journal of Animal Science and Technology
• /
• v.64 no.3
• /
• pp.539-563
• /
• 2022

Nine pig farms were evaluated for the welfare quality in Korea using animal- and environment-based parameters (particularly air quality parameters) during the winter of 2013. The Welfare Quality^® (WQ^®) protocol consists of 12 criteria within four principles. The WQ^® protocol classifies farms into four categories ranging from 'excellent' to 'not classified'. Each of these criteria has specific measures for calculating scores. Calculations for the welfare scores were conducted online using the calculation model in the WQ^® protocol. Environment-based parameters like microclimate (i.e., temperature, relative humidity, air speed, and particulate matter), bacteria (total airborne bacteria, airborne total coliform, and airborne total Escherichia coli), concentration of gases (carbon dioxide, ammonia, and hydrogen sulfide) were measured to investigate the relationship between animal- and environment-based parameters. Correlations between the results of animal- and environment-based parameters were estimated using spearman correlation coefficient. The overall assessments found that five out of nine farms were 'acceptable', and four farms were 'enhanced'; no farm was 'not classified'. The average score for the four principles across the nine farms, in decreasing order, were 'good feeding' (63.13 points) > 'good housing' (59.26 points) > 'good health' (33.47 points) > 'appropriate behaviors' (25.48 points). In the result of the environment aspect, the relative humidity of farms 2 (93.4%), 3 (100%), and 9 (98%) was much higher than the recommended maximum relative humidity of 80%, and four out of the nine farms had ammonia concentrations greater than 40 ppm. Ammonia had negative correlations with 'positive social behaviors' and positive emotional states: content, enjoying, sociable, playful, lively, happy and it had positive correlations with negative emotional states: aimless, distressed. The concentration of carbon dioxide had negative correlations with positive emotional states; calm, sociable, playful, happy and it had a positive correlation with negative emotional state; aimless. Our results indicate that the control of the environment for growing pigs can help improve their welfare, particularly via good air quality (carbon dioxide, ammonia, hydrogen sulfide).

• Restorative Dentistry and Endodontics
• /
• v.38 no.1
• /
• pp.11-20
• /
• 2013

Objectives: In most retrospective studies, the clinical performance of restorations had not been considered in survival analysis. This study investigated the effect of including the clinically unacceptable cases according to modified United States Public Health Service (USPHS) criteria into the failed data on the survival analysis of direct restorations as to the longevity and prognostic variables. Materials and Methods: Nine hundred and sixty-seven direct restorations were evaluated. The data of 204 retreated restorations were collected from the records, and clinical performance of 763 restorations in function was evaluated according to modified USPHS criteria by two observers. The longevity and prognostic variables of the restorations were compared with a factor of involving clinically unacceptable cases into the failures using Kaplan-Meier survival analysis and Cox proportional hazard model. Results: The median survival times of amalgam, composite resin and glass ionomer were 11.8, 11.0 and 6.8 years, respectively. Glass ionomer showed significantly lower longevity than composite resin and amalgam. When clinically unacceptable restorations were included into the failure, the median survival times of them decreased to 8.9, 9.7 and 6.4 years, respectively. Conclusions: After considering the clinical performance, composite resin was the only material that showed a difference in the longevity (p < 0.05) and the significantly higher relative risk of student group than professor group disappeared in operator groups. Even in the design of retrospective study, clinical evaluation needs to be included.

• Journal of Environmental Science International
• /
• v.18 no.7
• /
• pp.781-796
• /
• 2009

The current standard level of Heat Health Watch Warning System consider both daily maximum temperature and daily maximum heat index(HI), but current standard could not consider daily maximum HI due to the difficulties in forecasting when we consider both daily maximum temperature and daily maximum HI and no considering HI because relative humidity could not observed for some regions. So, Newly established standard level of Heat Health Watch Warning System is based on daily maximum temperature exceeding $30^{\circ}C$ for two consecutive days or daily minimum temperature exceeding $25^{\circ}C$ and daily maximum temperature exceeding $30^{\circ}C$. These days are called "extreme heat days". On extreme heat days, the standard of extreme heat advisory is based on daily maximum temperature among exceeding $32.7^{\circ}C$ and not exceeding $34.8^{\circ}C$, and extreme heat warning is based on daily maximum temperature exceeding $34.8^{\circ}C$. ANOVA analysis was carried out using the data of Seoul Metropolitan City in 1994 to check the robustness of the new standard level of Heat Health Watch Warning System from this study, in particular for mortality variable. The results reveal that the new standard specifies excess mortality well, showing significance level of 0.05 in the difference of excess mortality for each phase.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.34 no.8
• /
• pp.1319-1330
• /
• 2010

This study examines the underwear purchase behaviors of female consumers based on fashion leadership. Data research was conducted on 348 females in their 20s and 30s located in the city of Seoul & the surrounding Gyeonggi provincial area. The SPSS 17.0 software program was used to conduct data analyses such as descriptive statistics, frequency analysis, factor analysis, cluster analysis, ANOVA, and Scheffe's test as a post-hoc analysis. The results of this study are as follow. 1. Fashion leadership was identified with four factors; fashion opinion leadership, fashion innovation, confidence of fashion, and potential fashion leadership. Customers were segmented into the following three subdivisions: fashion leaders, fashion followers, and fashion laggards. 2. The factors derived from the factor analysis of underwear purchase motive included pursuit of fashion, economic, and fashion coordination. Fashion leaders highly regarded the pursuit of fashion & fashion coordination, but fashion laggards regarded economics highly. 3. The factors derived from the factor analysis of selection criteria included design attributes, brand attributes, functionality of clothes, and practicality. Fashion leaders regarded the attributes of design and brands highly; fashion followers regarded design attributes highly. 4. The factors derived from the factor analysis of underwear attitude included fashion/shopping orientation, fashion coordination orientation, and wear sensation/modesty orientation. Fashion leaders regarded fashion, shopping, design, and fashion coordination orientation highly relative to fashion followers and fashion laggards. 5. Fashion leadership showed significant differences in purchase motives, selection criteria, and underwear attitude.

• Health Policy and Management
• /
• v.19 no.4
• /
• pp.98-120
• /
• 2009

The purpose of this study is to elicit preference for drug listing decision criteria and to estimate the ICER threshold in South Korea using the discrete choice experiment (DCE) method. To collect the data, a DCE survey was administered to a subject sample either educated in the principle concepts of pharmacoeconomics or were decision makers within that field. Subjects chose between alternative drug profiles differing in four attributes: ICER, uncertainty, budget impact and severity of disease. The orthogonal and balanced designs were determined through computer algorithm to take the optimal set of drug profiles. The survey employed 15 hypothetical choice sets. A random effect probit model was used to analyze the relative importance of attributes and the probabilities of a recommendation response. Parameter estimates from the models indicated that three attributes (ICER, Impact, Severity of disease) influenced respondents' choice significantly(p${\pm}$0.001). In addition, each parameter displayed an expected sign. The Lower the ICER, the higher the probability of choosing that alternative. Respondents also preferred low levels of uncertainty and smaller impact on health service budget. They were also more likely to choose drugs for serious diseases rather than mild or moderate ones. Uncertainty however is not statistically significant. The ICER threshold, at which the probability of a recommendation was 0.5, was 29,000,000 KW/QALY in expert group and 46,500,000 KW/QALY in industry group. We also found that those in our sample were willing to accept high ICER to get medication for severe diseases. This study demonstrates that the cost-effectiveness, budget impact and severity of disease are the main reimbursement decision criteria in South Korea, and that DCE can be a useful tool in analyzing the decision making process where a variety of factors are considered and prioritized.

• Land and Housing Review
• /
• v.2 no.3
• /
• pp.269-276
• /
• 2011

Recently, the chance of dew condensation in apartment buildings is increasing because of several reasons. For example, ventilation rate has been decreased because of high-insulations and airtightness for saving energy. Besides, the humidity has been made by drying washes, cooking and bathing inside of apartment buildings. However, there is lack of resonable design criteria for preventing condensation in real life and real surroundings. Therefore, this study is aimed at making a resonable design criteria of preventing condensation by measuring the indoor temperature and humidity in real life. In addition to this, it is aimed at making a resonable outdoor condition and classifying regions by using weather data. The following are the results. The interior criterion for condensation was set up $25^{\circ}C$ and a relative humidity of 55%. The outdoor criterion for condensation was set up $20^{\circ}C$, $-15^{\circ}C$, and $10^{\circ}C$ respectively for the hard frost, middle, and southern areas.

• Magazine of the Korea Concrete Institute
• /
• v.8 no.6
• /
• pp.235-243
• /
• 1996

The mechanical behavior ot concrete is strongly influenced by various scenarios of crack initiation and crack propagation. Recently. the study of the interface fracture and cracking in interfacial regions is emerged as an important field, in the context of the developement of high performance concrete composites. The crack path criterion for elastically homogeneous materials is not valid when the crack advances at an interface because. in this case, the consideration of the relative magnitudes of the fracture toughnesses between the constituent materials and the interface are involved. In this paper, a numerical method is presented to obtain the values of two interfacial fracture parameters such as the energy release rate and the phase angle at the tip of an existing interface crack. Criteria based on energy release rate concepts are suggested for the prediction of crack growth at the interfaces and an hybrid experimental-numerical study is presented on the two-phase beam composite models containing interface cracks to investigate the cracking scenarios in interfacial regions. In general, good agreement between the experimental results and the prediction from the criteria is obtained.