• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.6
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• pp.147-154
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• 2014

The cable damages of the bridge structures induce very important impact on the structural safety, which implies the close monitoring of the cable damage is required to secure sustained safety of the bridges. Most usual available maintenance techniques are based on the monitoring the change of the natural frequency of the structures by damages. However, existing method are based on vibration method to calculate lateral vibration and system identification can calculate the axial stiffness using sensitivity equation by trial error method. But the frequency study by the longitudinal movement need because of the sag effect in system identification. This study proposes a new method to investigate the damage magnitudes and status. The method improves the accuracies in the magnitudes and status of damages by adopting the natural frequency of longitudinal movement. The study results have been validated by comparing them with the approximate solution of FEM. Thus, the relationship of cable damage and frequency appear with relation that the severe damage has the little frequency. If we know the real frequency we can estimate the cable damage severity using this relationship. This method can be possible the efficient management of the cable damage.

• Korean Journal of Food Science and Technology
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• v.27 no.4
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• pp.582-592
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• 1995

To measure rheological properties of the starch dough, an Extrusion Capillary Viscometer(ECV) cell was self-made and attached to Instron machine(Model 1140). Apparent viscosities of corn and waxy corn starch doughs were measured and their gelatinization degrees were determined by enzymatic analysis. When corn and waxy corn starch doughs with $36{\sim}52%$ moisture content were heated at $60{\sim}100^{\circ}C$, come-up time of the cold point of doughs decreased from 220 sec to 140 sec with increased in the moisture content. In the measurement range of $36{\sim}52%$ moisture content and $60{\sim}100^{\circ}C$ heating temperature, both corn and waxy corn starch doughs showed pseudoplastic flow behaviors. At the same shear rate, both shear stress and viscosity of starch dough decreased as the moisture content increased. At the moisture content above 44%, the shear stress and viscosity of starch dough decreased as the heating temperature increased from $60^{\circ}C\;to\;70^{\circ}C$, but increased as the heating temperature increased from $80^{\circ}C\;to\;100^{\circ}C$. When the moisture content increased and heating temperature, the gelatinization degree of starch dough increased from about 10% to about 62%. The gelatinization degree of waxy corn starch dough was $15{\sim}20%$ higher than that of corn starch dough under the same gelatinization conditions. The effects of moisture content on the viscosity of starch dough were examined by Arrhenius equation. As the moisture content increased, viscosity of starch dough decreased. But the effect of moisture content was greater in the range of $80{\sim}100^{\circ}C$ than in the range of $60{\sim}70^{\circ}C$ heating temperature.

• Journal of Korean Society of Forest Science
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• v.90 no.5
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• pp.650-662
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• 2001

The growth and yield models for five different kinds of natural forest types were systemically developed in the natural Broadleaved-Korean pine Forests in Northeast China. The data were collected from 359 temporary plots and 58 permanent plots with area ranged from 0.06 ha to 1.0 ha, ranging in stand age from 43 to 364 years. The Site Class Index (SCI) was introduced to evaluate site quality and the Crown Competition Factor (CCF) was selected as a measure of stand density for the mixed natural forest. The Chapman-Richards function was adopted to develop SCI equation and height-diameter curve. The Schumacher growth function was selected as base model to develop the DBH, basal area, and stand volume growth models by using re-parameterized method. In modeling mean DBH and basal area growth, it was found that the asymptotic parameter A of Schumacher function was exponentially related to site quality (SCI) and stand density (CCF). The rate parameter k was related to stand density and it was independent of SCI. Several validation measures for predicted stand variables were evaluated in the growth and yield models using independent data sets. The results indicated that relative mean errors (RME) in predicted stand attributes were less than ${\pm}5%$ and the estimated precision values of the stand variables were all greater than 95%.

• Journal of Digital Convergence
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• v.18 no.3
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• pp.259-266
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• 2020

This paper attempted to find the convergence factors related to the organizational citizenship behavior of hospital administration staff(HAS). The survey was conducted on 274 administrative staff at 22 hospitals in J regions randomly selected using self-administered questionnaires. The survey period took about a month from July 1 to July 31, 2019. The hierarchical multiple regression analysis shows the following results. The organizational citizenship behavior of respondents turned out to be significantly higher in following groups: The higher the procedure justice, sub-areas of organization justice, the higher the intragroup trust, and the higher the organizational commitment. Their explanatory power was 41.9%. The results of the study indicate that the efforts, to increase organization justice, intragroup trust and organizational commitment, are required to improve organizational citizenship behavior among HAS. The above results are expected to be utilized in human resource management and industrial health education of medical institutions that enhance organizational citizenship behavior of HAS. Later research requires the establishment of a structural equation model that affects organizational citizenship behavior of HAS.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.1
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• pp.128-134
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• 2014

To develop a crab-like flavorant from snow crab cooker effluent (SCCE, $20^{\circ}Brix$), optimal reaction conditions were determined using response surface methodology (RSM) combined with reaction flavoring technology (RFT). Using five variables (proline, glycine, arginine, methionine, fructose), RSM based on a five-level central composite design was applied to evaluate sensory acceptance (odor, taste, and overall acceptance) as dependent variables. A model equation obtained from RSM showed 0.88 of R-square for odor, 0.90 for taste, and 0.95 for overall acceptance with 0.07 lack of fit in overall acceptance (P<0.05). Odor score (predicted value) was 7.21 in the saddle point. Optimal flavoring conditions for making a crab-like flavorant were as follows: addition of 0.29 g of proline, 0.63 g of glycine, 0.61 g of arginine, 0.02 g of methionine, and 1.07 g% (w/v) of fructose into SCCE with RFT (90 min at $130^{\circ}C$). Odor score obtained under optimal conditions was 7.56, which was higher than the predicted value.

• Culinary science and hospitality research
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• v.19 no.3
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• pp.57-72
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• 2013

This study carried out an empirical analysis on the long-term effects of a marketing communication strategy used as a means of promotion(advertisement, free gift) of Christmas cake despite its high costs. Such verification results were considered to provide as important core elements for successful management in the bakery industry. By utilizing SPSS and AMOS, exploratory factor analysis(EFA) and confirmatory factor analysis(CFA) were conducted for the validity of the measurement items, and Structural Equation Model(SEM) was performed to verify the hypothesis. The analysis result is as follows. First, advertisement attribute(${\beta}$=0.269, t=4.512, p,<0.001) and free gift attitude(${\beta}$=0.293, t=5.043, p<0.001) had a positive influence on trust. Second, trust had a positive influence on purchase intention(${\beta}$=0.513, t=8.677, p<0.001). Third, advertisement attribute(${\beta}$=0.104, t=1.966, p,<0.05) and free gift attitude(${\beta}$=0.204, t=3.817, p<0.001) had a positive influence on purchase intention. Lastly, advertisement attitude appeared different by advertisement types(actors and animation), and ads with an actor were evaluated high than animation ads. Also, gift attitude appeared different by gift types(speaker doll/character hat and turtleneck muffler), and a turtleneck muffler was evaluated high than a speaker doll or a character hat.

• Journal of Korean Society of Forest Science
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• v.77 no.3
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• pp.322-330
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• 1988

This study was analyzed the behavior of recreational use through interviewing visitors with the questionnaire (1986.11-1987.9) in Mt. Kyeryong National Park. The number of visitors have been forecasted by tune series data of the past number of visitors, population, GNP, and number of cars (1974-1986) in korea. The results of the study can be summarized as follows : 1) Visitor's subjective evaluation about recreational environment evaluated to be fair in Mt. Kyeryong National Park. 2) They preferred natural forest resources to historic remains, tourist facility, etc.. 3) Number of participation was mostly once or five times over. 4) Visitors were affirmative to re-visit to the Mt. Kyeryong National Park. 5) Most of visitors stay for one day. 6) The most suitable estimated user regression model was : Y=-5753.7350+0.1726 Pop. -0.6564 NO. of Car. According to this equation, the total number of visitors will he increased by 3% per year from 1,023 thousands people in 1987 to 1,698 thousands in 2000.

• Journal of Korean Society of Forest Science
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• v.88 no.1
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• pp.93-100
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• 1999

This study has been carried out to estimate aboveground and soil carbon contents in an average 39-year-old Quercus mongolica and 40-year-old Quercus variabilis stands in Chungju, Chungbuk. Ten sample trees were cut in each forest and soil samples were collected. Aboveground carbon content was estimated by the equation model $Wt=aD^b$ where Wt is oven-dry weight in kg and D is DBH in cm. Total aboveground carbon content was 48.85tonC/ha in Quercus mongolica stand and 57.49tonC/ha in Quercus variabilis stand. The proportion of each tree component to total aboveground carbon content was high in order of bolewood, branches, bolebark, and leaves in the two forests. Aboveground net primary production was estimated at 5.88tonC/ha in Quercus mongolica stand and 5.12tonC/ha in Quercus variabilis stand. Soil carbon content was 67.0tonC/ha in Quercus mongolica stand, 67.8tonC/ha in Quercus variabilis stand, and 54.7tonC/ha in Pinus densiflora stand. There was no significant difference in soil carbon content among the three forests.

• Korean Chemical Engineering Research
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• v.49 no.6
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• pp.857-864
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• 2011

Oxy-fuel combustion with many advantages such as high combustion efficiency, low flue gas flow rate and low NOx emission has emerged as a promising CCS technology for coal combustion facilities. In this study, the effects of the direct sulfation reaction on $SO_2$ removal efficiency were evaluated in a drop tube furnace under typical oxy-fuel combustion conditions represented by high concentrations of $CO_2$ and $SO_2$ formed by gas recirculation to control furnace combustion temperature. The effects of the operating parameters including the reaction temperature, $CO_2$ concentration, $SO_2$ concentration, Ca/S ratio and humidity on $SO_2$ removal efficiency were investigated experimentally. $SO_2$ removal efficiency increased with reaction temperature up to 1,200 due to promoted calcination of limestone reagent particles. And $SO_2$ removal efficiency increased with $SO_2$ concentrations and the humidity of the bulk gas. The increase of $SO_2$ removal efficiency with $CO_2$ concentrations showed that $SO_2$ removal by limestone was mainly done by the direct sulfation reaction under oxy-fuel combustion conditions. From the impact assessment of operation parameters, it was shown that these parameters have an effects on the desulfurization reaction by the order of the Ca/S ratio > residence time > $O_2$ concentration > reaction temperature > $SO_2$ concentration > $CO_2$ concentration > water vapor. The semi-empirical model equation for to evaluate the effect of the operating parameters on the performance of in-furnace desulfurization for oxy-fuel combustion was established.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2007.11a
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• pp.109-113
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• 2007

This paper introduces a system, Simulation based Stochastic Markup Estimation System (S2ME), for estimating optimum markup for a project. The system was designed and implemented to better represent the real world system involved in construction bidding. The findings obtained from the analysis of existing assumptions used in the previous quantitative markup estimation methods were incorporated to improve the accuracy and predictability of the S2ME. The existing methods has four categories of assumption as follows; (1) The number of competitors and who is the competitors are known, (2) A typical competitor, who is fictitious, is assumed for easy computation, (3) the ratio of bid price against cost estimate (B/C) is assumed to follow normal distribution, (4) The deterministic output obtained from the probabilistic equation of existing models is assumed to be acceptable. However, these assumptions compromise the accuracy of prediction. In practice, the bidding patterns of the bidders are randomized in competitive bidding. To complement the lack of accuracy contributed by these assumptions, bidding project was randomly selected from the pool of bidding database in the simulation experiment. The probability to win the bid in the competitive bidding was computed using the profile of the competitors appeared in the selected bidding project record. The expected profit and probability to win the bid was calculated by selecting a bidding record randomly in an iteration of the simulation experiment under the assumption that the bidding pattern retained in historical bidding DB manifest revival. The existing computation, which is handled by means of deterministic procedure, were converted into stochastic model using simulation modeling and analysis technique as follows; (1) estimating the probability distribution functions of competitors' B/C which were obtained from historical bidding DB, (2) analyzing the sensitivity against the increment of markup using normal distribution and actual probability distribution estimated by distribution fitting, (3) estimating the maximum expected profit and optimum markup range. In the case study, the best fitted probability distribution function was estimated using the historical bidding DB retaining the competitors' bidding behavior so that the reliability was improved by estimating the output obtained from simulation experiment.