• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.5
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• pp.601-608
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• 2014

In this paper, we have characterized the electrical properties related to gate leakage current in AlGaN/GaN MISHFETs with varying the thickness (0 to 10 nm) of $Al_2O_3$ gate insulator which also serves as a surface protection layer during high-temperature RTP. The sheet resistance of the unprotected TLM pattern after RTP was rapidly increased to $1323{\Omega}/{\square}$ from the value of $400{\Omega}/{\square}$ of the as-grown sample due to thermal damage during high temperature RTP. On the other hand, the sheet resistances of the TLM pattern protected with thin $Al_2O_3$ layer (when its thickness is larger than 5 nm) were slightly decreased after high-temperature RTP since the deposited $Al_2O_3$ layer effectively neutralizes the acceptor-like states on the surface of AlGaN layer which in turn increases the 2DEG density. AlGaN/GaN MISHFET with 8 nm-thick $Al_2O_3$ gate insulator exhibited extremely low gate leakage current of $10^{-9}A/mm$, which led to superior device performances such as a very low subthreshold swing (SS) of 80 mV/dec and high $I_{on}/I_{off}$ ratio of ${\sim}10^{10}$. The PF emission and FN tunneling models were used to characterize the gate leakage currents of the devices. The device with 5 nm-thick $Al_2O_3$ layer exhibited both PF emission and FN tunneling at relatively lower gate voltages compared to that with 8 nm-thick $Al_2O_3$ layer due to thinner $Al_2O_3$ layer, as expected. The device with 10 nm-thick $Al_2O_3$ layer, however, showed very high gate leakage current of $5.5{\times}10^{-4}A/mm$ due to poly-crystallization of the $Al_2O_3$ layer during the high-temperature RTP, which led to very poor performances.

• Korean Journal of Applied Biomechanics
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• v.22 no.3
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• pp.305-314
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• 2012

The purpose of this study was to investigate the effects of joint kinetics and coordination on within-individual differences in maximum vertical jump. 10 male subjects aged 20 to 30 performed six trials in maximum vertical jump and with based on jump height the good(GP) and bad(BP) performances for each subject were compared on joint kinetics of lower extremity and coordination parameters such as joint reverse and relative phase. The results showed that maximum moment, power, and work done of hip joint and maximum moment of ankle joint in GP were significantly higher than that in the BP but no significant differences for the knee joint. We could observe a significant difference in joint reverse timing between both conditions. And also the relative phase on ankle-knee and ankle-hip in GP were significantly lower than that in the BP, which means that in GP joint movements were more in-phase synchronized mode. In conclusion, mechanical outputs of hip and ankle joints had an effect on within-individual differences in vertical jump and the inter-joint coordination and coordination including sequence and timing of joint motion also might be high influential factors on the performances within individual.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.2
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• pp.471-476
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• 2006

Chongmyung-tang(CMT, 聰明湯), oriental herbal medicine which consists of Polygaglae Radix(遠志), Acori Graminei Rhizoma(石菖蒲) and Hoelen(白茯神) has effect on amnesia, dementia. In order to evaluate effect of CMT on memory and learning in mice, CMT extract was used for studies. This paper describes the effects of CMT extract on memory and learning processes by using the passive and active avoidance performance tests, novel object recognition task and water maze task. The CMT extract ameliorated the memory retrieval deficit induced by ethanol in the passive avoidance responses but did not affect ambulatory activity of normal mice. These results suggest that CMT has an ameliorating effect on memory retrieval impairment. CMT extract decreased spontaneous motor activity(SMA) in the latter sessions of memory registration in active avoidance responses. These results suggest that CMT has partly transquilizing or antianxiety effects. In novel object recognition task to measure visual recognition memory, CMT-administered mice enhanced in long term memory for 1-3 days. In water maze task to measure spatial learning, which requires the activation of NMDA receptors in the hippocampus, spatial learning in CMT-administered mice was faster than in wild-type mice. These results suggest that CMT enhances memory and activates NMDA receptors.

• Journal of Mushroom
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• v.19 no.3
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• pp.134-139
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• 2021

A diverse group of plant-growth promoting bacteria were isolated in button mushroom (Agaricus bisporus) media to investigate the plant-growth promoting traits of compounds including indole acetic acid (IAA), ammonia, 1-aminocyclopropane-1-carboxylic acid deaminase, siderophore, and hydrogen cyanide. Twenty-one bacterial strains showing positive effects for all the test traits were selected and classified to confirm bacterial diversity in the media habitat. Plant-growth promoting traits of the isolates were also assessed. All strains produced IAA ranging from 20 ㎍/mL to 250 ㎍/mL. Most of the isolates produced more than 80% siderophore. Four strains (Pantoea sp., PSB-08, Bacillus sp., PSB-13, Pseudomonas sp., PSB-17, and Enterobacter sp., PSB-21) showed outstanding performances for all the tested traits. In a bioassay of these four strains using mung bean plant, the best growth performances (23.16 cm, 22.98 cm, 2.27 g/plant, and 1.83 g/plant for shoot length, root length, shoot dry weight, and root dry weight, respectively) were obtained from the plants co-inoculated with Bacillus sp., PSB-13. The resultant data indicate that button mushroom media have got a diverse group of bacteria with plant growth promoting abilities. Thus, the media could be a good recycling resource for using to an effective bio-fertilizer.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.1121-1124
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• 2004

Carbon Nitride exhibits high electrical resistivity and thermal conductivity that are similar to the properties shown by diamond-like carbon (DLC) films. These diamond-like transport properties in Carbon Nitride come in a material consisting of $sp^2$-bonded carbon versus the $sp^3$-carbon of DLC. The diamond-like properties and nondiamond-like bonding make NDLC an attractive candidate for applications. Liquid crystal (LC) alignment capabilities with ion beam exposure on carbon nitride thin films and Electro-Optical (EO) performances of the ion-beam aligned twisted nematic liquid crystal display (TN-LCD) with oblique ion beam exposure on the Carbon Nitride thin film surface were studied. An excellent uniform alignment of the nematic liquid crystal (NLC) alignment with the ion beam exposure on the Carbon Nitride thin films was observed. In addition, the good EO properties of the ion-beam-aligned TN-LCD were achieved. Finally, we achieved the residual DC property of the ion-beam- aligned TN-LCD on the Carbon Nitride thin film.

• Journal of Korean Academic Society of Home Health Care Nursing
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• v.6
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• pp.46-58
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• 1999

The purpose of this research was to find out the state of the nursing performance of the home care nurses in Seoul in order to provide the data for the practical work guide. The data were collected from fifty home care nurses working in 22 institutions located in Seoul. The research tool used for this research was modified and tested by Song Jong-Rye(1999) which was originally modified the standard tool of American Nurses Association (1998) and was partly supplement and adjusted for this research. The reliability of this tool was Cronbach's $\alpha$=.0982. The collected data were statistically processed using SAS for t-test, ANOVA. $Scheff\'{e}$ test. Among the surveyees, 50% have been working as a home care nurse more than three years and 74.0% of them were married. And 52% have B.S degree with certification of home care nurse from the certification program for Home Care Nurses affiliated at nursing schools. Half of the home care nursing organizations were based on the general hospitals, and most(78%) of the responsible senior personnels of those organizations were nurses. The following results are drawn from this research. 1) The level of nursing performance by the task sectors General performance level of home care nurses was relatively high in grade of 3.06 from total 4.00. Among the task sectors. the ethical field scored the highest points, and the next were nursing intervention, professional training, and data gathering, and the research sector scored the lowest point. 2) The level of nursing performance by general features of home care nurses Statistically relevant correlation between performance according to the duration of working experience as a nurse(p=0.8951) and performance according to the duration of working as home care nurse(p=0.2263) did not emerge. Also, performance by marriage status(p=0.2218), education(p=0.5733), and taking the certification program for home card nurse(p =0.1560) has no statistically meaningful correlation. 3) The level of nursing performance by the type of home care nursing organizations There exists a significant difference(p=0.002) between performances by the types of organizations. Most of the responsible senior personnels of the home care nursing organization were nurses. The level of nursing performance of the home care nursing organization under nurse management was relatively higher than that of home care nursing organizations led by medical doctors or non-medical professional, but this was not proved as statistically meaningful(p =0.3617). 4) The level of nursing performance by task sectors according to the characteristic of home care nursing service organization There exists a significant difference between nursing performances by task sectors according to the characteristics of home care nursing organization(p=0.002). In case of model research center of one College of Nursing, the nursing performance in the sectors of organization, theory, and data gathering were lower than that of in hospital based home care nursing service. And in case of local home care centers, performances in sectors of organization, theory, data gathering, nursing intervention. professional training, and research sectors were significantly low. Based on the obtained results, overall performance of home care nurses can be appraised as relatively good. Especially, performances in sectors of the nursing intervention, nursing plan. and data gathering including the in direct nursing were recorded high scores. From this, it can be concluded that high quality of nursing is relatively practicing for home patients at these days. Since the high quality of nursing for patients was directly related to the level of nursing performances of home care nurses, it is required to improve practical performance level of them by making constant evaluation and running continual education program and supplementing curriculum for the sectors with low scores.

• The Journal of the Korea Contents Association
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• v.10 no.12
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• pp.477-491
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• 2010

This paper aimed to understand current trends in online lectures for Korean SAT based on students' academic performances through a qualitative interview approach. In results, the highest academic performance group showed a good deal of interest and usage in online lectures. This group participants preferred private online lectures to public ones. However, the lowest academic group liked to use public online lectures. The middle academic groups who lived in an expensive area spent a lot of money for tutoring or attending private institutes rather than online lectures. Suggestions are: self-regulated learning is needed, public onilne lectures should have improved contents, and lastly, these online lectures are required to be connected with regular school curriculum.

• International Area Studies Review
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• v.13 no.2
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• pp.190-222
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• 2009

This study is for analyzing the management performances of Korean tourism firms, which have been operating as preparing strategically against FTA, one of the most importantly external environment in international management since in the middle of 1990s. The main purpose can be mentioned to test empirically some relations between the management performances of Korean tourism ones and the levels of understanding and preparing against FTA. In detail speaking, the dependent variables of management performances are classified with sales, profits and management satisfaction, while the independent ones regarding with FTA are sorted based on the previous studies with the 2 following factors like understanding/preparing of managers and one of workers in a firm. This study is conducted in two stages. Firstly, the research model is designed by the reviewing relevant theories, previous studies. Secondly, the survey of Korean tourism enterprises engaging in management activities in Korea is implemented by collecting questionnaires. And for testing the hypothesis, the analyzing tools are being used for correlation, reliability, validity and multi regression on SPSS 12.0 for windows and finally the path analysis of structural equation modeling is activated with AMOS 7.0 for windows.

• Journal of Practical Agriculture & Fisheries Research
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• v.19 no.1
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• pp.129-137
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• 2017

This study was conducted to investigate of growth performances and net assimilation rate(NAR) of Allium microdictyon Prokh. distributed inland and Allium ochotense Prokh. originated Ulleung-do. The Allium microdictyon on the growth of 1-2 years showed the largest relative growth rate, and showed high relative growth from three to four years. Allium ochotense on the growth from one year to three years showed high relative growth rate. The T/R rate of Allium ochotense of 2~5years was in the range of 0.4~0.5. However, The T/R rate of Allium microdictyon was increased as increasing with age. This implies that Allium microdictyon was consumed more energy on growing subterranean part. The LWR of 1~3years old Allium ochotense. was showed more smaller than 4~5years old. It seems that the growth characteristics of Allium ochotense 1-3 years after sowing the leaf growth consume more energy than Allium microdictyon. Net assimilation rate(NAR) of Allium ochotense for 1-3 years after sowing was higher than that of Allium microdictyon. In this time, the material of Allium ochotense has a higher production efficiency can be seen indirectly.

• The Journal of Information Technology
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• v.5 no.1
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• pp.113-131
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• 2002

The purpose of this study is to investigate the influences of transaction information and reputation about alliance partner on opportunism and alliance performance. In this study, a structural model and several hypotheses were developed regarding the relationships between transaction term, transaction records, reputation of alliance partner, opportunism, and alliance performance. Based on the collected data, the structural model was analyzed with Lisrel 8.12. The results can be summarized as follows. First, the longer the transaction term, the lower the opportunism and the higher the perceived alliance performances. Second, the better the transaction records, the lower the opportunism and the higher the perceived alliance performances. Third, the reputation of alliance partner company has not any influence on the opportunism and the perceived alliance performances. Finally, the lower the opportunism of alliance partner, the higher the perceived alliance performances. At the end of the paper, managerial implications and future research directions are discussed.