• Journal of the Korea society of information convergence
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• v.1 no.1
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• pp.47-54
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• 2008

This study analyzed the status and causes for the dropouts of college based on the survey conducted among 14,210 freshmen attending D College, other than the supernumerary special selection, from 2001 through 2005. A significant difference was shown in all items of general characteristics. The dropout rate of women, generally selected and general highschool graduated were higher than for men, specially selected and special high school graduated, respectively. The most dropouts were due to Not Return(40.16%), followed by Unenrolled(32.98%), Voluntary Leave(26.05%) and Expelled(0.81%) in order. In the distribution of the central tendency values measured from the entire subjects, the high school records and the days of absence showed a positive skewness, while the college records showed a negative skewness with the data mostly around a higher grade. The standard deviation indicating that the dropouts got the scores higher than those of the continuing students demonstrated that there was relatively insignificant difference in scores between two groups. It was demonstrated that both the high school records and the days of absence affected the dropout. The lower the high school records were, and the more the days of absence were, the more influence both items had on the dropout. The influence degree of each item was similar. Lower the scores were in terms other than the first term in the freshmen year, the more influence it had on the dropout. The most dropouts were influenced by the scores of the freshmen year, followed by the credits of the second term, the scores of the first term, the scores of the second term, and the credits of the first term in the freshmen year. Among the general characteristic items, the most dropouts were influenced by the course of study, followed by the gender. The effect of other items was insignificant.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.48 no.6
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• pp.88-96
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• 2011

Underwater acoustic communication is applicable in various areas, such as ocean data collection, undersea exploration and development, tactical surveillance, etc. Thus, robot control system construction used for underwater-robot like AUV or ROV is essential in these areas. In this paper, we propose the Message Merging MAC($M^2$-MAC) protocol, which is suitable for real time robot control system, considering energy efficiency in important parts of underwater acoustic sensor network constitution. In this proposed MAC protocol, gateway node receives the data from robot nodes according to the time slots that were allotted previously. And messages delivered from base-station are generated to one MAC frame by buffering process. Finally, generated MAC frames are broadcasted to all robot nodes in the cluster. Our suggested MAC protocol can also be hybrid MAC protocol, which is successful blend of contention based and contention-free based protocol through relevant procedure with Maintenance&Sleep (M&S) period, when new nodes join and leave as an orphan. We propose mathematical analysis model concerned about End-to-End delay and energy consumption, which is important factor in constructing real-time robot control system. We also verify the excellence of performance according to comparison of existing MAC protocols with our scheme.

• 전자공학회논문지 IE
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• v.46 no.3
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• pp.6-11
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• 2009

In this paper, manufactured composite nanofiber by electrospinning that make spinning solvent according to weight of PAN/PVdF. PVdF content of composite nanofiber decreases, diameter of fiber decreased. Result that measure contact angle to confirm hydrophile property of PAN/PVdF composite nanofiber, PVdF content increases, could confirm that contact angle with water increases. After leave filter measurement sample for 25 hours in temperature of $40^{\circ}C$, humidity of 85%, result PAN/PVdF composite nanofiber that estimate efficiency could confirm that display performance of HEPA more than 99.95% and ULPA more than 99.999%. And fiber diameter is small, could confirm that filter performance increases. Tensile strength of bulk of PAN/PVdF composite nanofiber was 5-8MPa, expansion 100-300%. And strength and expansion could know that increase according as PVdF's content increases. Tensile strength was 3-8MPa degree after annealing PAN/PVdF composite nanofiber during 2 hours in 120t. Tensile strength was no change almost by annealing, and expansion could know that decrease.

• Journal of Bio-Environment Control
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• v.5 no.1
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• pp.1-6
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• 1996

For reducing planting distance in greenhouse grown watermelon(Citrullus vulgaris S.) this experiment was carried out to study the effect of DIF on stem elongation and growth. Day temperatures ranged from $25^{\circ}C$ to 35$^{\circ}C$ : night temperatures ranged from $25^{\circ}C$ to 35$^{\circ}C$ at 5$^{\circ}C$ interval. Stem elongation, leaf size, dry weight and flowering were influence by day and night temperatures. Stem elongation and length of internode decrease with increasing night temperature at same day temperature. The optimums for number of leaves categories was with day at 35$^{\circ}C$, and flower production was the lowest at $25^{\circ}C$. Total leaf area meter was maximized at 35/30(DT/NT), but for size pet one leave was the largest 25/25(DT/NT). Responses of leaf size per leaves were similar to that of internode length, with maximum day and night at $25^{\circ}C$. Total plant dry weight was the highest 35/30 (DT/NT) and minimum occurring at 25/30(DT/NT). The shoot/root ratios of dry weight Increased with day temperature up to 3$0^{\circ}C$ and were the highest with night at $25^{\circ}C$. Chlorophyll contents decreased with decreasing day and night temperature.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.4 no.2
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• pp.1-19
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• 2009

American Psychiatric Association defined hwa-byung as a unique mental illness of Korea, a kind of anger syndrome. This illness caused by the Korean culture is more often found on women than men, especially middle-aged women. The cause of hwa-byung mainly depends on the traditional family structure of Korea formed by Confucianism. Other causes that many middle-aged women suffer from hwa-byung are that their low education level originated in their wrong-recognized position in society and poverty in the past makes them not to be able to control their minds effectively(social psychological factor), and that they get stressed and depressed because of loss of their position in the family after their children leave home and the menopause which hurts their feminine beauty (physiological factor). So, this program aims at letting them to; 1) experience catharsis of the negative feelings which causes hwa-byung by expressing in psychodrama, 2) ease the symptoms of hwa-byung by relaxing their mind, 3) understand themselves through sharing their feelings and thinking at the group level, 4) acquire the opportunities to stabilize and expand their role in their real lives through the role playing.

• Journal of muscle and joint health
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• v.6 no.2
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• pp.253-277
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• 1999

Patients with chronic disease have various treatment patterns because it shows a progressive degenerative feature. Especially various physical and emotional problems of the rheumatoid arthritis patients leave them shopping around various types of treatment. According to previous studies, over 70% of patients with arthritis experienced the traditional oriental medicine or folk remedies simultaneously with medical treatment within one year after the onset of disease. The purposes of this study are 1) to compare the patterns of treatment-seeking behaviors between Korean arthritis patients and Americans ; and 2) test two models of treatment-seeking behaviors by path analysis, one for early treatment-seeking behavior model(ETBM) and the other is chronic treatment-seeking behavior model (CTBM) in Korean sample. The interview survey was performed to 133 RA patients with structured questionnaire at out-patient clinic or public health center. Patients characteristics such as age, duration of disease were similar in two countries except higher educational background in Americans. There were no patients using only alternative therapies or no medical treatment in the US. Most of the American patients have chosen both medical treatment and alternative therapy, while the Koreans less than American. In Korea, combined treatment group usually consists of the people who are younger, more educated and higher economic status than the characters of other groups in early or chronic stages. In early stage, they tend to have strong belief of curing from the disease, satisfy the relationship with their physicians and comply with direction of the medical professional. The paths of two models were explained by 70% in ETBM and 33% in CTBM. When the models were modified, almost all paths of the CTBM were the same as the previous one, but direct determinant factor was changed from the relationship with physicians to the lay referral system in chronic model. These two models' explanation powers became 94% and 88%, respectively. The attitude or perception of disease, lay referral system and the relationship with medical personnel are the main determinants of treatment-seeking behaviors.

• Research in Plant Disease
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• v.22 no.1
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• pp.50-54
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• 2016

In early June 2014, leaf spot symptoms were observed on black chokeberry (Aronia melanocarpa) in Yesan-gun and Geumsan-gun, Chungcheongnam-do in Korea. The initial symptoms on leave surfaces were brown small-circular spots with a yellow halo lesion, and gradually the small spots were fused, all of infected leaves dropped eventually. A fungus were isolated from the initial lesion, and cultured on potato dextrose agar. Colony color on upper surface of plate varied from olive gray to charcoal gray. Size of conidia mostly extend to $19-50{\times}5-9{\mu}m$ in nature and $20-59{\times}8-13{\mu}m$ in culture, with 3-8 transverse septa and usually no longitudinal septum or only 1 longitudinal septum in 1-3 of the transverse compartments, and also have a short or long beak. Pathogenicity was investigated using wounded or unwounded black chokeberry and apple leaves. After 7 days of inoculation, leaf spots were similar to the symptoms naturally occurred in the field. On the basis of mycological characteristics, pathogenicity, and ITS rDNA sequence analysis, this fungus was identified as Alternaria mali. This is the first report of Alternaria leaf spot on black chokeberry caused by A. mali in Korea.

• Research in Plant Disease
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• v.22 no.4
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• pp.257-263
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• 2016

Chlorella is known as chlorophyceae which can live autotrophically by photosynthesis, promote the growth of plants and suppress some plant diseases. However, a few researches in inhibition mechanism of plant diseases by chlorella have been carried out. In this study cucumber leaves pre-treated with Chlorella fusca suspension were investigated whether anthracnose by Colletotrichum orbiculare is suppressed or not. Furthermore, in order to illustrate how the algae can restrain the antracnose, the infection structures of C. orbiculare were observed on the cucumber leaves pre-treated with the algae. Consequently, appressorium formation rate was apparently reduced in the cucumber leaves pre-treated with C. fusca compared to untreated control one. Also, the numbers of conidia found at the inoculation sites were significantly reduced compared to untreated one. On the other hand, on the leaves pre-treated with $Benomyl^{(R)}$ appressorium formation were decreased remarkably and numbers of conidia were also reduced similar with those pre-treated with C. fusca. Based on these results, it was revealed that occurrence of anthracnose can be suppressed by C. fusca pre-treatment and suggested that biochmical or structural hinderance by C. fusca resulting in the decline of appressorium formation on the leave surfaces may play an important role in the disease suppression.

• Applied Chemistry for Engineering
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• v.24 no.4
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• pp.438-442
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• 2013

In the present work, electroless plating was used for coating thin films consisting mainly of Ni and P on carbon fiber. Structural changes appeared upon the post-annealing at various temperatures of the Ni-P film on carbon fiber was studied using various analysis methods. Scanning, a flat surface structure of Ni-P film on carbon fiber was found after electroless plating of Ni-P film on carbon fiber without post-annealing, whereas annealing at $350^{\circ}C$ resulted the formation of porous structures. With increasing the annealing temperature to $650^{\circ}C$ with an interval of $50^{\circ}C$, the pore size increased, but the density decreased. X-ray diffraction (XRD) showed the existence of metallic Ni, and Ni-P compounds before post-annealing, whereas the post-annealing resulted in the appearance of NiO peaks, and the decrease in the intensity of the peak of metallic Ni. Using X-ray photoelectron spectroscopy (XPS), phosphorous oxides were detected on the surface upon annealing at $650^{\circ}C$, and $700^{\circ}C$, which can be attributed to the phosphorous compounds originally existing in the deeper layers of the Ni films, which undergo sublimation and escape from the film upon annealing. Escape of phosphorous species from the bulk of Ni-P film upon annealing could leave a porous structure in the Ni films. Porous materials can be of potential applications in diverse fields due to their interesting physical properties such as high surface area, and methods for fabricating porous Ni films introduced here could be easily applied to a large-scale production, and therefore applicable in diverse fields such as environmental filters.

• Korean journal of food and cookery science
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• v.22 no.4 s.94
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• pp.495-503
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• 2006

The purpose of this study was to analyze the effect of the consumer-brand relationship quality on the brand loyalty in family restaurants. Questionnaires were distributed to 320 students in K University located in Masan, who were sampled by convenience-sampling method. The surveys were conducted from November, 10 to 24, 2005. Of the 287 returned questionnaires, 15 unusable questionnaires were excluded to leave 272 for use in the final analysis(response rate: 85.0%). For the statistical analysis, SPSS(12.0)was used to conduct the descriptive analysis, factor analysis, reliability analysis, correlation and multiple regression analysis. The results of this study showed that 2 constructs (satisfaction and intimacy) of consumer-brand relationship quality have significantly positive effects on the brand loyalty in family restaurants(p<.01). This indicates that as consumer-brand relationship quality strengthens, the customer's brand loyalty increases. In conclusion, food service managers in family restaurants should focus on the marketing strategies to strengthen the quality of consumer-brand relationship in order to increase the brand loyalty of customers.