• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.917-923
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• 2002

Inhibitory mechanism of the anticoagulant polysaccharide purified from Codium fragile was investigated. The anticoagulant compounds (Cf-30-IV-4-ii, CF-30-IV) prolonged the clotting time at both activated partial thrombo-plastin time (aPTT) and thrombin time (TT). The Inhibition factor assay of instrinsic coagulation pathway in the blood showed that the anticoagulant polysaccharide (CF-30-IV-4-ii) inhibited other factors such as Ⅷ, Ⅸ, Ⅵ and Ⅷ of the coagulation cascade, which did not affect the lupus anticoagulant AB activity. In the thrombin inhibition pattern the CF-30-IV-4-ii did not directly influence the fibrine formation mediated by thrombin but af-fected the anticoagulant activity through the activation of antithrombin III. Base on these result, the anticoaglant polysaccharide (CF-30-IV-4-ii) was considered to inhibit serine pretense involved in the blood coagulation cascade through the enhancing antithrombin III activity. The residual effects of anticoagulant activity and antithrombosis were tested with ICR mice. The anticoagulant polysaccharide (CF-30-W) kept its anticoagulant activitv for 6 hrs with 100% survival at a dose of 150 mg/kg in the antithromboisis test. The anticoagulant effect of CF-30-RF in ex vivo was proportional to the concentration of intravenously injected dose up to 100 mg/kg.

• Magazine of the Korean Society of Agricultural Engineers
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• v.22 no.4
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• pp.108-114
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• 1980

A deterministic conceptual erosion model which simulates detachment, entrainment, transport and deposition of eroded soil particles by rainfall impact and flowing water is presented. Both upland and channel phases of sediment yield are incorporated into the erosion model. The algorithms for the soil erosion and sedimentation processes including land and crop management effects are taken from the literature and then solved using a digital computer. The erosion model is used in conjunction with the modified Kentucky Watershed Model which simulates the hydrologic characteristics from watershed data. The two models are linked together by using the appropriate computer code. Calibrations for both the watershed and erosion model parameters are made by comparing the simulated results with actual field measurements in the Four Mile Creek watershed near Traer, Iowa using 1976 and 1977 water year data. Two water years, 1970 and 1978 are used as test years for model verification. There is good agreement between the mean daily simulated and recorded streamflow and between the simulated and recorded suspended sediment load except few partial differences. The following conclusions were drawn from the results after testing the watershed and erosion model. 1. The watershed and erosion model is a deterministic lumped parameter model, and is capable of simulating the daily mean streamflow and suspended sediment load within a 20 percent error, when the correct watershed and erosion parameters are supplied. 2. It is found that soil erosion is sensitive to errors in simulation of occurrence and intensity of precipitation and of overland flow. Therefore, representative precipitation data and a watershed model which provides an accurate simulation of soil moisture and resulting overland flow are essential for the accurate simulation of soil erosion and subsequent sediment transport prediction. 3. Erroneous prediction of snowmelt in terms of time and magnitute in conjunction with The frozen ground could be the reason for the poor simulation of streamflow as well as sediment yield in the snowmelt period. More elaborate and accurate snowmelt submodels will greatly improve accuracy. 4. Poor simulation results can be attributed to deficiencies in erosion model and to errors in the observed data such as the recorded daily streamflow and the sediment concentration. 5. Crop management and tillage operations are two major factors that have a great effect on soil erosion simulation. The erosion model attempts to evaluate the impact of crop management and tillage effects on sediment production. These effects on sediment yield appear to be somewhat equivalent to the effect of overland flow. 6. Application and testing of the watershed and erosion model on watersheds in a variety of regions with different soils and meteorological characteristics may be recommended to verify its general applicability and to detact the deficiencies of the model. Futhermore, by further modification and expansion with additional data, the watershed and erosion model developed through this study can be used as a planning tool for watershed management and for solving agricultural non-point pollution problems.

• Journal of Distribution Science
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• v.16 no.8
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• pp.79-89
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• 2018

Purpose - This research aims to investigate the factors that influence consumer's overseas online shopping behavior. Consumers adopt overseas online shopping as a new buying way and more and more consumers prefer overseas online shopping than traditional shopping ways. Consumers' behaviors in this shopping experience can be different from other shopping experiences. With the increase of overseas online shopping, we need to find antecedents and results of overseas online shopping. Especially there would be positive or negative factors which influence overseas online shopping motivation. To find the relationship, this study examines self-efficacy and impulsivity as major factors which influence overseas online shopping. We also suggest that several attitude factors increase self-efficacy and it is positively related to customer satisfaction. On the other hand, we assume that overseas online shopping factors influence impulsivity of buying and it will decrease customer satisfaction. Research design, data, and methodology - This empirical study data were collected from Korean people who experience overseas online shopping. The subjects for this study were confined to shoppers who used overseas online shopping within the past six months. A total of 267 responses were gathered. SPSS 23.0, PLS 2.0 software were used in the data analysis. Descriptive statistics were used to show sample characteristics. We examined reliability, validity test for constructs. All measurement items used seven-point scales(1= very strong disagree, 7 = very strongly agree) drawn from previously published papers. Partial Least Square method was applied to find the relationship between antecedent factors and dependent factors and hypotheses were estimated. Results - Results show that perceived superiority, perceived ease of use, perceived transaction safety, perceived behavioral control positively affect self-efficacy. Self-efficacy influences positively to consumer's post purchase satisfaction. Perceived monetary benefit and perceived uniqueness motivated impulse buying. This can make consumer's post purchase dissatisfaction. Conclusions - This paper attempted to confirm the existence of both the positive and negative faces of overseas online shopping. The result reveals that self-efficacy is a major factor which may increase satisfaction in the overseas online shopping. Usually, we can think monetary benefit and uniqueness of products motivate overseas online shopping. But it can also intrigue impulse buying and negatively affect customer relationship. Therefore companies should provide enough products information to their potential customers and they might apply adequate processes such as recommendation, comparing systems to build long term relationship with their customers.

• Journal of the Korea Concrete Institute
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• v.14 no.4
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• pp.503-512
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• 2002

Generally, the girder spacing of the two-girder composite bridge is from 5m up to 15m. To ensure the structural safety according to Korean Bridge Design Specification, the deck depth should be from 33 cm upto 73 cm. Using the transversal prestressing strands in concrete deck, we can reduce its depth about 10％. However, there is little experience on the design and construction of prestressed concrete(PSC) decks in Korea. This paper focuses on the behaviors of PSC deck. A literature survey is performed widely. Considering the characteristics of the two-girder bridge and the construction conditions in Korea, a cast-in-place PSC deck is recommended for the two-girder bridge with 6m girder spacing. To examine its structural behaviors and safety, three partial model deck specimens(3 m$\times$5 m) with real scale are fabricated md tested. One(PS34-RS) is 34cm depth with the stiffness restraint in longitudinal edges for simulating the real bridge deck. Another(PS34-NS) is same depth without the stiffness restraint, and the other(PS28-NS) is 28cm depth with the stiffness restraint. Under the static patch loading, each specimen had a larger ultimate flexural strength than the design value. Specimens with the stiffness restraint (PS34-RS and PS28-RS) showed the punching shear failure mode and specimen without that(PS34-NS) showed the flexural failure mode.

• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.1
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• pp.136-143
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• 2006

In this study, recently it is urgently required that demolition waste concrete has to be recycled on the construction because urban development is accelerated and redevelopment project is rapidly expanded, production quantity of construction and demolition waste concrete is being increased. As a results of drying shrinkage test under restrained and unrestrained condition, although workability and mechanical properites of concrete using HQRS were similar to that of concrete using natural sand, there were a great difference in deformation characteristic of dry shrinkage according to replacement ratio of HQRS. And, it makes sure that use of HQRS instead of partial nature sand was effective because drying shrinkage of concrete using 30 volume percentage of HQRS was smaller than that using only natural sand. Therefore, it is the objective of this study to provide the fundamental data about the re-application as an analysis of the drying shrinkage characteristics of concrete using HQRS and it is able to creta a high value-added by using HQRS.

• Journal of the Korean Data and Information Science Society
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• v.28 no.2
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• pp.261-270
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• 2017

This research aims to investigate how healthcare professionals can control their behaviors in the internet and the status of their Internet addiction, thus emphasizing appropriate internet ethics awareness of students majoring in healthcare-related field, the future healthcare professionals. The goal of this research is to verify the mediating effect of self-control between the status of internet addiction of healthcare-related college students and their internet ethical awareness. A questionnaire survey was conducted on 236 students majoring in healthcare-related fields in 5 universities located in D city from March to April, 2016. The result of analyzing correlation of Internet addiction, internet ethics awareness, and self-control shows that self-control is negatively correlated with internet addiction but positively correlated with internet ethics awareness. The result of research suggests that self-control does have partial mediation effect on internet addiction and internet ethical awareness. Accordingly, it is necessary to develop mediator program that enhances self-control in order to improve internet ethical awareness of healthcare-related college students and develops measures to prevent addition to the internet, one of the primary cause of decline in internet ethics awareness.

• Journal of the Korean Chemical Society
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• v.53 no.6
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• pp.717-726
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• 2009

Multivariate models were developed for the simultaneous spectrophotometric determination of copper (II), nickel (II) and zinc (II) in water with 1-(2-thiazolylazo)-2-naphthol as chromogenic reagent in the presence of Triton X-100. To overcome the drawback of spectral interferences, principal component regression (PCR) and partial least square (PLS) multivariate calibration approaches were applied. Performances were validated with several test sets, and their results were then compared. In general, no significant difference in analytical performance between PLS and PCR models. The root mean square error of prediction (RMSEP) using three components for $Cu^{2+}$, $Ni^{2+}$ and $Zn^{2+}$ were 0.018, 0.010, 0.011 ppm, respectively. Figures of merit such as sensitivity, analytical sensitivity, limit of detection (LOD) were also estimated. High reliability was achieved when the proposed procedure was applied to simultaneous determination of $Cu^{2+}$, $Ni^{2+}$ and $Zn^{2+}$ in synthetic mixture and tap water.

• Journal of Korean Dental Science
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• v.4 no.2
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• pp.46-51
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• 2011

Purpose: For aesthetic reasons, composite resin brackets are widely used. However, related studies are rare. This pilot study sought to compare the stress distributions in two commercially available composite resin brackets with metal slot. Materials and Methods: Two commercially available resin brackets -- full-metal slot resin bracket (fSRB) and partial-metal slot resin bracket (pSRB) with straight wire appliance dimension of $0.022{\times}0.028$ in -- were selected. In each bracket, 3-dimensional finite element models were constructed, and stress level was evaluated using finite element analysis. By loading the tipping force and torsion moment, which are similar to those applied by the stainless steel rectangular wire ($0.019{\times}0.025$ -in), stress distributions were calculated, and von Mises stress values were obtained. Results: In pSRB and fSRB, the stress value of the torque moment was much higher than that of the tipping force. The pSRB showed higher stress value than fSRB in both tipping force and torque moment because of the difference in size and configuration of the metal frame inserted into the slot. More stress was also found to be concentrated on the slot area than the wing area in fSRB. Conclusion: The slot form of fSRB was found to be more resistant to the stress of tipping and torque than the slot form of pSRB. In addition, the slot areas -- rather than the wing areas -- of the bracket showed breakage susceptibility. Therefore, resistance to the torque moment on the slot area should be considered in bracket design.

• Management & Information Systems Review
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• v.33 no.4
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• pp.99-118
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• 2014

Using the theory of attribution, this study investigates the determinants if controllability and explores underlying dimensions of online information credibility, and then investigates if the credibility of online information influences the users' intention to use the online information for evaluating or judging the involved products. Moreover, as a research attempt to investigate the impacts of online information credibility, this study examines whether the main effect of perceived online information credibility on the intention of using online information to make a decision of purchase is mediated by both perceived risk and perceived usefulness. A total of 287 survey forms were collected from online consumers. We examined reliability by exploring internal consistency of the multiple item scales in the overall sample. Convergent and discriminant validity were also examined for evidence of construct validity. Then, PLS technique was employed to test the research model. As a result of analyzing data from a dataset of 287 responses via PLS technique, it is found that (1) both sources (controllability and stability) of perceived credibility are significantly associated with both perceived risk and perceived usefulness, and (2) perceived risk as well as perceived usefulness partially mediate the link between the two sources of credibility and intention to use. The findings of this study also suggest that the two dimensions of online information credibility influence information recipient's intention to use. Moreover, the online information including descriptions about controllability and stability can trigger potential consumers to perceive risk about consumption of the informed products and services. Therefore, providing online information with highly described controllability and stability can increase not only the credibility of the online information itself, but also the intention to use the online information through perceived risk and usefulness.

• Culinary science and hospitality research
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• v.21 no.5
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• pp.98-108
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• 2015

The provincial education office considers providing school lunch as a foodservice and intends to improve consumer satisfaction. This study investigates the effect of student food habits and perceived food quality on satisfaction with school lunch based on Oliver's expectancy disconfirmation theory. We test the moderating effect of student gender and school conditions, such as the location of the school, job positon of the nutrition teacher, renovating kitchen and food distributing place. Questionnaires were collected from 240 sixth graders in the eight elementary schools in Gyeonggi province from August to September 2014. Excluding inadequate questionnaires, 208 were analyzed. PLS (Partial Least Square) and bootstrap t-tests were conducted for this study. The results showed food habits affected satisfaction directly (p<0.01). The perceived food quality of the school lunch service mediated this relationship in part (p<0.01). Moderating effects identified were gender (p<0.1), nutrition teacher's position(p<0.05), and renovating kitchen (p<0.1), but not location of school or distributing place. The study revealed the importance of student food habits and perceived food quality, which had an influence on satisfaction. We make a distinction between the concepts of satisfaction and quality so as to improve student satisfaction. When it comes to offering education program about food habits, the schools with old-fashion kitchen is given priority to than renovating one.