• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.10
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• pp.1701-1706
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• 2013

Domestic and overseas information with regard to harmful substances are analyzed. From the results, environmental-derived hazard chemicals, which show relatively low recognition, and hazard chemicals that occur unavoidably in food manufacturing process are selected as target harmful substances. Thus, educational leaflet contents were developed based on these substances. To find the effects of education with the above contents, this study surveyed 120 female college students living in Seoul. The purpose of the survey is to analyze the change in recognition, attitude and behavior on hazard chemicals in foods. The survey found that the recognition on harmful substance in foods increased; from 31.5~78.0% before education to 98.8% after education. It also indicates that vague anxiety in which the harmful substances may damage their health decreased by approx. 25.0%; from 77.8% before education to 52.8% after education. For the question of what they would do when government promotes to reduce harmful substances in foods, 12.3% of respondents said that they would actively follow the suggestions and 73.5% of them said that they would do their best before an education. However, 56.1% of them said that they would actively follow the suggestions after the education. It indicates that the ability to recognize harmful substances changed after the education. With regard to consumer behavior, when they knew about the harmful substances in foods, 49.6% of them said that they would select foods after investigating relevant information before the education, while 77.4% of them said that after the education; which is an increase of 27.8%. Further, 45.4% of them said that they would not purchase relevant foods before the education, while 20.9% of them said that after the education; which is a decrease of 24.5%. Therefore, it is considered that vague anxiety of consumers can be eliminated by providing persuasive information on harmful substances. To expand on the communication channel with consumers for food safety, contents development and educational promotion should be enhanced for providing food safety related information.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.12 no.3
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• pp.75-86
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• 2017

The development of web technologies and the generalization of smartphones have dramatically increased the number of social media users using the Internet. As a result, companies are perceived social media as a major marketing tool and operate a variety of SNS channels. In particular, start-ups conducting businesses with limited resources, social media is being used as an effective marketing tool to meet many potential customers at a low cost. Among them, facebook is the most used channel in the world and plays an important promotional tool not only in overseas but also in marketing activities of domestic start-ups. The purpose of this study is to analyze the relationship between satisfaction and purchase intention according to four personal characteristics of users who use social media contents and to measure the mediating effect of satisfaction on the relationship between content type and purchase intention. To this end, we classified into three types based on the previous research, and social media content is provided to 200 fans of Minbak Danawa(Minda), one of representative start-ups related to accommodation, The questionnaires were conducted for 3 weeks, and a total of 145 copies were collected. All the collected questionnaires were used for statistical analysis through SPSS 18.0. The empirical results show that all three types of content, such as task-oriented, self-oriented, and interaction-oriented, have a significant effect on the satisfaction level. Among them, it is confirmed that the satisfaction level plays a mediating role on the relationship between task-oriented contents and purchase intention. And the user 's personal characteristics showed a partially moderate effect on the satisfaction according to the content type. Therefore, social media content provided by corporations has an important effect on consumer satisfaction and purchasing, in order for start-up to prevail in the market, it is necessary to have an operational strategy to communicate with customers continuously through systematic contents analysis and planning. The result of this study suggests effective ways to build a social media marketing strategy for start-ups and suggests ways to utilize contents considering the characteristics of internet users.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.2 no.1
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• pp.1-17
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• 1982

The stream morphological characteristics of a river basin has a close correlation with the hydrological and hydraulic characteristics of the basin. In this study the correlations of flow duration and Hydraulic geometry with the stream morphological characteristics as well as the correlation between flow duration and hydraulic geometry were analyzed bases on the data for the Geum River basin. The purpose of this study was to provide the necessary informations for water utilization projects at ungauged locations along the river course. First of all, the stream morphological characteristics was analyzed based on the Horton's three laws on the morphology of a stream that is, the law of stream number, the law of average stream length and the law of average stream slope. As is the case for majority of the rivers it was found that the Geum River basin was well developed according to the Horton's laws. High correlations were also found between the basin characteristics and the channel characteristics. The flow duration curves obtained with the daily stream flow data of 10~90% frequency of occurences at the five stage gauging stations in the Geum River could, in general, be expressed as an exponential functional relationship. The concept of proportional stream ordering system was employed to describe continuously the longitudinal variation of the stream morphological characteristics, and the mathematical model was formulated for the discharge-frequency-proportional stream order relationship. With the morphological characteristics as a common parameter the relationships with flow duration, drainage area were established in mathematical expressions, respectively.

• Clinical and Experimental Pediatrics
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• v.51 no.9
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• pp.992-997
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• 2008

Purpose : Hypertension (HTN) is no longer an exclusively adult disease; the prevalence of pediatric HTN is increasing. To understand the evaluation and treatment of childhood HTN in Korea, we investigated, via a questionnaire, how hypertensive children are currently assessed and managed by pediatric cardiologists (CA) and nephrologists (NE). Methods : We surveyed 82 pediatric CA and 77 NE, regarding how they manage hypertensive children in Korea. Results : A total 75 replies were received to our questionnaire request (response rate: 47.15%). Routine blood pressure (BP) checks were more frequently performed by NE (CA: 5.7%, NE: 25%, P=0.03), but most respondents (86%) did not check BP routinely. Mercury sphygmomanometers were the most commonly used devices and ambulatory blood pressure monitoring was not frequently used. The goal BP in treated patients was set at the 95th percentile by 61% of respondents. NE used a lower BP goal in hypertensive children with renal disease (CA: 24%, NE: 64%, P=0.004) or DM (CA: 12.5%, NE: 50%, P=0.003). Angiotensin converting enzyme (ACE) inhibitors were the most commonly used agents (mean: 59%); following ACE inhibitors, CA preferred diuretics for hypertensive children with renal disease or cardiovascular disease, and NE preferred calcium channel blockers, regardless of underlying disease. Self-monitoring was the most frequent method for BP monitoring at home. Conclusion : In Korea, BP measurement is not yet a routine examination in treating hypertension. There are some differences in management strategies vis-$\grave{a}$-vis hypertension, between pediatric cardiologists and nephrologists. For the appropriate management and prevention of secondary disease in long-term studies, standard guidelines and education are needed for pediatricians.

• Korean Journal of Biological Psychiatry
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• v.5 no.1
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• pp.95-101
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• 1998

The changes of electroencephalogram(EEG) in patients with dementia of Alzheimer's type are most commonly studied by analyzing power or magnitude in traditionally defined frequency bands. However because of the absence of an identified metric which quantifies the complex amount of information, there are many limitations in using such a linear method. According to the chaos theory, irregular signals of EEG can be also resulted from low dimensional deterministic chaos. Chaotic nonlinear dynamics in the EEG can be studied by calculating the largest Lyapunov exponent($L_1$). The authors have analyzed EEG epochs from three patients with dementia of Alzheimer's type and three matched control subjects. The largest $L_1$ is calculated from EEG epochs consisting of 16,384 data points per channel in 15 channels. The results showed that patients with dementia of Alzheimer's type had significantly lower $L_1$ than non-demented controls on 8 channels. Topographic analysis showed that the $L_1$ were significantly lower in patients with Alzheimer's disease on all the frontal, temporal, central, and occipital head regions. These results show that brains of patients with dementia of Alzheimer's type have a decreased chaotic quality of electrophysiological behavior. We conclude that the nonlinear analysis such as calculating the $L_1$ can be a promising tool for detecting relative changes in the complexity of brain dynamics.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.23 no.3
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• pp.143-150
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• 2017

Effects of packaging methods for maintaining the shelf-life and postharvest quality of Korean chive (Allium tuberosum Rotter) usually called buchu in Korea was studied during fall season. Buchu, which has high moisture content and active metabolism after harvest, is characterized by the greater changes in quality during storage and distribution. It is usually packaged in paper box during distribution in domestic channel in Korea where the marketability ends within few days of harvest. In order to maintain the commercial quality of buchu, we tried to use inner film with or without absorbent paper in commercial paper box packaging. The 'Greenbelt' cultivar of buchu was harvested in october and packaged in corrugated paper box (A), in corrugated paper box with micro-perforated high density polyethylene (HDPE) film as inner material (B), a layer of absorbent paper both at the bottom and top of buchu in corrugated paper box (C) and a combination of HDPE film as inner material along with a layer of absorbent paper both at the bottom and top of buchu in corrugated paper box (D), and stored at $5^{\circ}C$ for up to 21 days. Several quality parameters such as fresh weight loss, respiration rate, color, chlorophyll content and sensory qualities were monitored during storage. When buchu was packaged only in paper box, the appearance and quality deteriorated rapidly through decay development thereby sample became unmarketable within 12 days. On the other hand, buchu packaged with inner HDPE film maintained its quality, good visual appearance and exhibited a longer period of marketable life compared to the samples stored in other treatments. However, the use of absorbent paper did not have any significant effect in maintaining quality of buchu. The uses of inner HDPE film was effective in reducing weight loss that resulted better visual appearance of buchu. Results suggest that the use of inner HDPE film in bulk type corrugated paper box packaging and storing at $5^{\circ}C$ could be the optimum condition for commercial storage of buchu. Further investigation on other quality parameters and packaging methods would be useful in maintaining the quality aspects of buchu at postharvest stages.

• Investigative Magnetic Resonance Imaging
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• v.18 no.2
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• pp.107-119
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• 2014

Purpose : To efficiently evaluate phased array coil performance using a software tool box with which we can make visual comparison of the sensitivity of every coil element between the real experiment and EM simulation. Materials and Methods: We have developed a $C^{{+}{+}}$- and MATLAB-based software tool called Phased Array Coil Evaluator (PACE). PACE has the following functions: Building 3D models of the coil elements, importing the FDTD simulation results, and visualizing the coil sensitivity of each coil element on the ordinary Cartesian coordinate and the relative coil position coordinate. To build a 3D model of the phased array coil, we used an electromagnetic 3D tracker in a stylus form. After making the 3D model, we imported the 3D model into the FDTD electromagnetic field simulation tool. Results: An accurate comparison between the coil sensitivity simulation and real experiment on the tool box platform has been made through fine matching of the simulation and real experiment with aids of the 3D tracker. In the simulation and experiment, we used a 36-channel helmet-style phased array coil. At the 3D MRI data acquisition using the spoiled gradient echo sequence, we used the uniform cylindrical phantom that had the same geometry as the one in the FDTD simulation. In the tool box, we can conveniently choose the coil element of interest and we can compare the coil sensitivities element-by-element of the phased array coil. Conclusion: We expect the tool box can be greatly used for developing phased array coils of new geometry or for periodic maintenance of phased array coils in a more accurate and consistent manner.

• The Korean Journal of Nuclear Medicine
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• v.38 no.5
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• pp.338-343
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• 2004

Purpose: The purpose of this study was to develop a small animal PET using dual layer phoswich detector to minimize parallax error that degrades spatial resolution at the outer part of field-of-view (FOV). Materials and Methods: A simulation tool GATE (Geant4 Application for Tomographic Emission) was used to derive optimal parameters of small PET, and PET was developed employing the parameters. Lutetium Oxyorthosilicate (LSO) and Lutetium-Yttrium Aluminate-Perovskite(LuYAP) was used to construct dual layer phoswitch crystal. $8{\times}8$ arrays of LSO and LuYAP pixels, $2mm{\times}2mm{\times}8mm$ in size, were coupled to a 64-channel position sensitive photomultiplier tube. The system consisted of 16 detector modules arranged to one ring configuration (ring inner diameter 10 cm, FOV of 8 cm). The data from phoswich detector modules were fed into an ADC board in the data acquisition and preprocessing PC via sockets, decoder block, FPGA board, and bus board. These were linked to the master PC that stored the events data on hard disk. Results: In a preliminary test of the system, reconstructed images were obtained by using a pair of detectors and sensitivity and spatial resolution were measured. Spatial resolution was 2.3 mm FWHM and sensitivity was 10.9 $cps/{\mu}Ci$ at the center of FOV. Conclusion: The radioactivity distribution patterns were accurately represented in sinograms and images obtained by PET with a pair of detectors. These preliminary results indicate that it is promising to develop a high performance small animal PET.

• Journal of Magnetics
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• v.20 no.4
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• pp.381-386
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• 2015

The purpose of this study is to improve diagnostic efficiency of clinical study by setting up guidelines for more precise examination with a comparative analysis of signal intensity and image distortion depending on the location of X axial of object when performing magnetic resonance diffusion weighted imaging (MR DWI) examination. We arranged the self-produced phantom with a 45 mm of interval from the core of 44 regent bottles that have a 16 mm of external diameter and 55 mm of height, and were placed in 4 rows and 11 columns in an acrylic box. We also filled up water and margarine to portrait the fat. We used 3T Skyra and 18 Channel Body array coil. We also obtained the coronal image with the direction of RL (right to left) by using scan slice thinkness 3 mm, slice gap: 0mm, field of view (FOV): $450{\times}450mm^2$, repetition time (TR): 5000 ms, echo time (TE): 73/118 ms, Matrix: $126{\times}126$, slice number: 15, scan time: 9 min 45sec, number of excitations (NEX): 3, phase encoding as a diffusion-weighted imaging parameter. In order to scan, we set b-value to $0s/mm^2$, $400s/mm^2$, and $1,400s/mm^2$, and obtained T2 fat saturation image. Then we did a comparative analysis on the differences between image distortion and signal intensity depending on the location of X axial based on iso-center of patient's table. We used "Image J" as a comparative analysis programme, and used SPSS v18.0 as a statistic programme. There was not much difference between image distortion and signal intensity on fat and water from T2 fat saturation image. But, the average value depends on the location of X axial was statistically significant (p < 0.05). From DWI image, when b-value was 0 and 400, there was no significant difference up to $2^{nd}$ columns right to left from the core of patient's table, however, there was a decline in signal intensity and image distortion from the $3^{rd}$ columns and they started to decrease rapidly at the $4^{th}$ columns. When b-value was 1,400, there was not much difference between the $1^{st}$ row right to left from the core of patient's table, however, image distortion started to appear from the $2^{nd}$ columns with no change in signal intensity, the signal was getting decreased from the $3^{rd}$ columns, and both signal intensity and image distortion started to get decreased rapidly. At this moment, the reagent bottles from outside out of 11 reagent bottles were not verified from the image, and only 9 reagent bottles were verified. However, it was not possible to verify anything from the $5^{th}$ columns. But, the average value depends on the location of X axial was statistically significant. On T2 FS image, there was a significant decline in image distortion and signal intensity over 180mm from the core of patient's table. On diffusion-weighted image, there was a significant decline in image distortion and signal intensity over 90 mm, and they became unverifiable over 180 mm. Therefore, we should make an image that has a diagnostic value from examinations that are hard to locate patient's position.

• Geophysics and Geophysical Exploration
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• v.7 no.3
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• pp.164-173
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• 2004

To delineate geothermal water movement at the Pohang geothermal development site, Self-Potential (SP) survey and monitoring were carried out during pumping tests. Before drilling, background SP data have been gathered to figure out overall potential distribution of the site. The pumping test was performed in two separate periods: 24 hours in December 2003 and 72 hours in March 2004. SP monitoring started several days before the pumping tests with a 128-channel automatic recording system. The background SP survey showed a clear positive anomaly at the northern part of the boreholes, which may be interpreted as an up-flow Bone of the deep geothermal water due to electrokinetic potential generated by hydrothermal circulation. The first and second SP monitoring during the pumping tests performed to figure out the fluid flow in the geothermal reservoir but it was not easy to see clear variations of SP due to pumping and pumping stop. Since the area is covered by some 360 m-thick tertiary sediments with very low electrical resistivity (less than 10 ohm-m), the electrokinetic potential due to deep groundwater flow resulted in being seriously attenuated on the surface. However, when we compared the variation of SP with that of groundwater level and temperature of pumping water, we could identify some areas responsible to the pumping. Dominant SP changes are observed in the south-west part of the boreholes during both the preliminary and long-term pumping periods, where 3-D magnetotelluric survey showed low-resistivity anomaly at the depth of $600m\~1,000m$. Overall analysis suggests that there exist hydraulic connection through the southwestern part to the pumping well.