• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.889-892
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• 2005

Standardized method based on extraction, filtration, and gas chromatography (GC) was developed far propylene glycol analysis to set hygienic norm of safety measure for foods under governmental control. Various columns were tested fur propylene glycol analysis by GC with flame ionization detector. Known amount of propylene glycol was spiked into wheat flour dough and analyzed by developed method. Results showed 101.60% recovery rate for propylene glycol with HP-5 column. Reproducibility test of standards recorded 0.30 for standard variation and 0,42% for relative variation. Using analytical method established, contents of propylene glycol in more than hundred different foods were monitored. Propylene glycol was detected in most foods, indicating propylene glycol is not only commonly added during food preparation, but also is contained naturally in food.

• Journal of Pharmaceutical Investigation
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• v.30 no.3
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• pp.173-178
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• 2000

The purpose of this work is to develop a transurethral suppository containing prostaglandin $E_1\;(PGE_1)$, which stabilizes the drug, gives no irritation to physiological body and enhances the erectile response of $PGE_1.\;PGE_1$ transurethral suppositories were prepared with various amounts of compositions such as saturated polyglycolysed glyceride $(Suppocire^{\circledR}\;AP,\;SAP)$, polyoxyethylene hydrogenated castor oil (HCO-50) and ethanol. The melting points, viscosities and $PGE_1$ release of the suppositories were investigated. Ocular irritation test was carried out after application of $PGE_1$ suppository to rabbit's eye. The intracavernous pressure (ICP), penile length and duration of erectile response were determined after transurethral administration of $PGE_1$ suppository and compared with those after intracavernosal injection of $PGE_1$ solution to cats. HCO-50 hardly affected the melting points and viscosities of $PGE_1$ suppositories. Additionally, $PGE_1$ transurethral suppositories, whose melting point ranges was $34-35^{\circ}C$, was speedily melted in physiological body. HCO-50 significantly decreased the dissolution rates of $PGE_1$ from the suppositories. Dissolution mechanism analysis showed the release of $PGE_1$ was proportional to the square root of time, indicating that $PGE_1$ might be released from the suppositories by Fickian diffusion. The release rate of $PGE_1$ from $PGE_1$ suppository [PGE1/SAP/HCO-50/ethanol (1/94.5/2.5/2%)] was about 80% within 2 h. This $PGE_1$ suppository gave no significant irritation to the ocular tissue, expecting that it gave no irritation to the urethral tissue less sensive than ocular tissue. Furthermore, $PGE_1$ in this suppository was stable at $4^{\circ}C$ for 2 years. This suppository increased the ICP and penile erection similar to those of injectable $PGE_1$ solution. However, it gave 2.5-fold increased duration of erectile response than injectable $PGE_1$ solution. Our results suggested that it gave more effective erectile response than injectable $PGE_1$ solution in cats. It is concluded that this $PGE_1$ suppository with good safety, excellent stability and enhanced erectile response, could be a more effective and convenient transurethal delivery system of $PGE_1$.

• Journal of Pharmaceutical Investigation
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• v.30 no.3
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• pp.191-199
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• 2000

Genomics is providing targets faster than we can validate them and combinatorial chemistry is providing new chemical entities faster than we can screen them. Historically, the drug discovery cascade has been established as a sequential process initiated with a potency screening against a selected biological target. In this sequential process, pharmacokinetics was often regarded as a low-throughput activity. Typically, limited pharmacokinetics studies would be conducted prior to acceptance of a compound for safety evaluation and, as a result, compounds often failed to reach a clinical testing due to unfavorable pharmacokinetic characteristics. A new paradigm in drug discovery has emerged in which the entire sample collection is rapidly screened using robotized high-throughput assays at the outset of the program. Higher-throughput pharmacokinetics (HTPK) is being achieved through introduction of new techniques, including automation for sample preparation and new experimental approaches. A number of in vitro and in vivo methods are being developed for the HTPK. In vitro studies, in which many cell lines are used to screen absorption and metabolism, are generally faster than in vivo screening, and, in this sense, in vitro screening is often considered as a real HTPK. Despite the elegance of the in vitro models, however, in vivo screenings are always essential for the final confirmation. Among these in vivo methods, cassette dosing technique, is believed the methods that is applicable in the screening of pharmacokinetics of many compounds at a time. The widespread use of liquid chromatography (LC) interfaced to mass spectrometry (MS) or tandem mass spectrometry (MS/MS) allowed the feasibility of the cassette dosing technique. Another approach to increase the throughput of in vivo screening of pharmacokinetics is to reduce the number of sample analysis. Two common approaches are used for this purpose. First, samples from identical study designs but that contain different drug candidate can be pooled to produce single set of samples, thus, reducing sample to be analyzed. Second, for a single test compound, serial plasma samples can be pooled to produce a single composite sample for analysis. In this review, we validated the issue whether the second method can be applied to practical screening of in vivo pharmacokinetics using data from seven of our previous bioequivalence studies. For a given drug, equally spaced serial plasma samples were pooled to achieve a 'Pooled Concentration' for the drug. An area under the plasma drug concentration-time curve (AUC) was then calculated theoretically using the pooled concentration and the predicted AUC value was statistically compared with the traditionally calculated AUC value. The comparison revealed that the sample pooling method generated reasonably accurate AUC values when compared with those obtained by the traditional approach. It is especially noteworthy that the accuracy was obtained by the analysis of only one sample instead of analyses of a number of samples that necessitates a significant man-power and time. Thus, we propose the sample pooling method as an alternative to in vivo pharmacokinetic approach in the selection potential lead(s) from combinatorial libraries.

• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.441-452
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• 2011

This study was carried out to survey the residual characteristics of endocrine disruptor (ED)-suspected pesticides in greenhouse soils and assess their leachabilites to groundwater. Greenhouse soils were collected from 40 sites of greenhouse in 2008 in Korea. Sixteen ED-suspected pesticides which had been using in Korea, such as alachlor, benomyl, carbaryl, cypermethrin, 2,4-D, dicofol, endosulfan, fenvalerate, malathion, mancozeb, metribuzin, metiram, methomyl, parathion, trifluralin, and vinclozolin, in the soils, were analyzed by chromatographic methods using GLC-ECD and HPLC-DAD/FLD. Limits of detection (LODs) of the test pesticides ranged from 0.0004 to 0.005 mg/kg. Recoveries of the target pesticides from soil ranged from 72.69 to 115.28%. Four pesticides including cypermethrin were detected in the range of from 0.001 to 2.019 mg/kg, representing that their detection rate from greenhouse soils was 37.5%. The highest detection rate was observed from endosulfan which was detected from 16 site soils of the total samples, indicating that endosulfan is persistent in soil because of its very low mobility and high adsorption characteristics in soil. Based on the groundwater ubiquity scores (GUSs) of the pesticides detected from greenhouse soils, most of them have little possibilities of groundwater contamination except the fungicide vinclozolin with some leaching potential because of high water solubility and very low soil adsorption property.

• Journal of Distribution Science
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• v.11 no.1
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• pp.45-53
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• 2013

Purpose - The environment-friendly agricultural product market in Korea sees continual high growth. Recently, the Korean government has been actively fostering environment-friendly agriculture as an engine of future growth. Korean people have increasingly become more health-conscious and interested in food safety issues. Many distribution and retailing companies have responded with various promotional activities. However, most of these are not strategic and appear to have unsatisfactory outcomes. The main purpose of this paper is to suggest effective marketing strategies for environment-friendly agricultural products. To achieve this aim, the study empirically investigates the effects of consumer characteristics and trust on the purchase intention of environment-friendly agricultural products. Research design, data, methodology - Based on the theory of planned behavior, and previous studies related to the purchase intention and consumption of environment-friendly agricultural products, we set up five study hypotheses. These related to the demographic characteristics of consumers, purchase intention, and behavior of the products. We then set up a study model and four study hypotheses relating to health consciousness, environmental consciousness, consumer trust level, purchase intention, and behavior of the products. The data were collected using a questionnaire given to consumers living in Seoul and southern Geonggi Province. The final sample size is 403 and mean age is 44.3. SPSS 15.0 for Windows and Amos 7.0 were used as statistical analysis tools. Meaningful results were derived using frequency analysis, correlation analysis, a t-test, and structural equation modeling. Results - Empirical results of this research are as follows. (1) First, it is shown that consumers consider such attributes as intimacy and health to be important when they buy environment-friendly agricultural products. (2) We also found that consumers recognize the value of environment-friendly agricultural products as high, but their trust level as low. (3) Consumer groups consisting of married couples, with higher education, higher income, and higher age are shown to have a higher intention of buying environment-friendly agricultural products than any other consumer group. (4) It is estimated that the level of consumer trust positively affects the purchase intention of environment-friendly agricultural products. The path coefficient (.138) between consumer trust and purchase intention is statistically significant at the α = .05 level. (5). It is also estimated that environmental consciousness positively affects purchase intention. The path coefficient (.245) between environmental consciousness and purchase intention is statistically significant at the α = 0.05 level. The standardized path coefficients of consumer trust and environmental consciousness with purchase intention are .556 and .288 respectively. Therefore, consumer trust affects purchase intention more than environmental consciousness. (6) Finally, purchase intention is estimated to positively affect purchase behavior. Conclusions - Based upon empirical results, this research suggests that marketers of environment-friendly agricultural products should focus more on increasing consumer trust levels, emphasizing the training and education of employees. The government also should pay attention to a standardized certification system for environment-friendly agricultural products. Marketers of environment-friendly agricultural products should consider the consumer groups of married couples, with higher education, higher income, and higher age as a major target segment.

• 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.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.5
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• pp.162-177
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• 2020

The perception of traffic environment based on various sensors in autonomous driving system has a direct relationship with driving safety. Recently, as the perception model based on deep neural network is used due to the development of machine learning/in-depth neural network technology, a the perception model training and high quality of a training dataset are required. However, there are several realistic difficulties to collect data on all situations that may occur in self-driving. The performance of the perception model may be deteriorated due to the difference between the overseas and domestic traffic environments, and data on bad weather where the sensors can not operate normally can not guarantee the qualitative part. Therefore, it is necessary to build a virtual road environment in the simulator rather than the actual road to collect the traning data. In this paper, a training dataset collection process is suggested by diversifying the weather, illumination, sensor position, type and counts of vehicles in the simulator environment that simulates the domestic road situation according to the domestic situation. In order to achieve better performance, the authors changed the domain of image to be closer to due diligence and diversified. And the performance evaluation was conducted on the test data collected in the actual road environment, and the performance was similar to that of the model learned only by the actual environmental data.

• Korean Journal of Childcare and Education
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• v.10 no.2
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• pp.111-131
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• 2014

This study aims to research the use of smart devices of infants and preschool children, and their mothers' perception about it. Moreover, the goal of this study is to collect preliminary data about problems from the use of smart devices, and to prevent the problems. Therefore, the questions of inquiry for this study are: 1. How do infants and preschool children use smart devices? 2. How do mothers perceive their children using smart devices? Four hundred and forty mothers, who send their child to a day-care center or kindergarten in Busan, participated in this research and data among 397 of them were analyzed using PASW 18.0 program. The answers to a multiple-choice question were converted into a frequency and percentage. To verify the difference of factors, Chi-squared Test and One-way Analysis of Variance methods were used. The following are findings of this study: 1. Most of the families owning smart devices allow their children to use a smart device when children want it, and children use it for entertainment purpose before their bedtime. Children start to use a smart device mostly around the age of 4. Compared to girls, boys spend a longer time on smart devices playing mobile game. In addition, the research indicated that the children of younger mothers tend to use smart devices in earlier ages than the children of elder mothers. 2. Mothers of preschool children have higher perception about the availability of their child using smart devices compare to the mothers of day-care center. However, the research showed that elder mothers have more positive perceptions about all the other five lower factors, (e.g. educational characteristic, entertainment characteristic, design, safety, and smart recognition).

• Korean Journal of Environment and Ecology
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• v.6 no.1
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• pp.72-85
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• 1992

The analysis of visitor's behavior in Hallasan National Park was executed for a month in september, 1990. In the characteristics of trip purpose, the nature-oriented motive was 68.9% of the total. And in the characteristics of the accompanied, the ratio of such items as company, friends,2-3 persons and above 12 persons was generally high. The ratio of lunch box was 62.7％ and the item of bring back waste treatment was 69.6% in the characteristic of activity. The degree of landscape satisfaction was 3.98 and comparatively high on considering the maximum degree of 5.0, but in the degree of facility, the degree of dissatisfaction was high. Therefore the degree of total satisfaction was 3.43. In the opinion of users, the entrance by order of arrival, the adoption of reserved system and the limitation of the entrance of a group were gen- orally objected but the adoptation of nature rest-rotation system was comparatively assented Specially, visitor center was rarely used but many visitor who has attended there positively think about it. In factor analysis, 4 factors were extracted. Facilitate, social. user behavior and natural property were the most affecting factor to psychological satisfaction test. Multiple regression results showed that cleanness, land-scape, safety, no. of wastebasket and crowdness items affected the total satisfaction variable in total and local area.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.39 no.6
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• pp.42-48
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• 2002

The design, construction and performance test of a convenient multi-purpose irradiator is described. A multi-purpose irradiator using Cesium-137 has been developed for studies of low dose radiation effects in biology and for calibration of Thermo Luminescent dosimeter(TLD). During the operation, three rods of radioactive material which are 10cm in length revolve 180 degrees and irradiate biological samples, or TLD, and return to their shielded position, after the programmed time. A programmable Logic Controller(PLC) controls the sequence of operation, interlock, motor rotation and safety system. The rotation speed of biological samples can vary up to 20 RPM. A real time monitoring system was also incorporated to check and control the operation status of the irradiator. The capacity of the irradiation chamber was 4.5 liters. The isodose distribution at arbitrary vertical planes was measured by using film dosimetry. The dose-rate was 0.13 cGy/min in air and 0.11 cGy/min in water equivalent material in the case of Cesium-137. Range of activity was 2 Ci. The homogeneity of dose distribution in the chamber was ${\pm}$7%. The actual radiation level on the surface was within permissible levels. The irradiator had a maximum 0.35 mR/min radiation leakage on its surface.