• The Korean Journal of Pharmacology
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• v.25 no.1
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• pp.23-30
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• 1989

Buprenorphine, one of the mixed agonist-antagonist opioid drugs was used to inverstigate the opioid receptor on frog sciatic nerve A fibers. Action potentials were recorded for 4 hrs by a sucrose gap apparatus which were separated by four rubber membranes. To examine the one of the mechanism of action of buprenorphine, meperidine or naloxone was added after or before the treatment of buprenorphine. The results of this experiment were as follows: 1. Buprenorphine suppressed significantly the compound action potentials of frog sciatic nerve, and the maximal effects were shown both at $10^{-4}\;M$ and at $10^{-8}\;M$. 2. The dose-response relationship of buprenorphine on the depressant effect in frog sciatic nerve was biphasic and inverted U-shaped. 3. Buprenorphine blocked the effect of Meperidine $(10^{-3}\;M)$ on this preparation. 4. The depressant effcct of Buprenorphine on frog sciatic nerve was blocked by $10^{-8}\;M$ naloxone. From the above results, buprenorphine acts as one of agoinist-antagonistic effect on frog sciatic nerve, and the opioid receptor on this preparation is located on or near the intracellular opening of the sodium channels, which are sensitive to naloxone.

• Korean journal of communication and information
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• v.19
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• pp.65-93
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• 2002

This research deals with meanings and issues of 'broadcasting area' in which trans-regional broadcasting media such as satellite broadcasting and webcasting provoked. The issues around broadcasting area have raised the examination of fundamental broadcasting philosophy in Korea, i.e. establishment of broadcasting area intends to foster new media development? or protect local culture and local journalism? After assessing current criticisms around the broadcasting area, this study particularly addresses re-transmission outside the broadcasting area, satellite broadcaster's re-transmission of terrestrial channels, and widening of broadcasting area. This research argues that broadcasting area has lost its raison-etre due to the advent of new communication technology, even though it was maintained to protect regional broadcasting stations. Therefore it argues that now is the right time to change the broadcasting area in the digital media era. This approach could strengthen the competitiveness of regional broadcasting stations and solve the rows surrounding broadcasting areas.

• Journal of the Korea Convergence Society
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• v.5 no.4
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• pp.101-106
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• 2014

Most peoples are used to prefer to view the video contents rather than the other contents since the video contents are more easy to understand with both their eyes and ears. As the wide spread use of smartphones, the demands for the contents services are increasing rapidly. To promote the contents business, it's important to provide security of subscriber authentication and corresponding communication channels through which the contents are delivered. Generally, symmetric key encryption scheme is used to protect the contents in the channel, and the session key should be upadated periodically for the security reasons. In addition, to protect viewing paid contents by illegal users, the proxy authentication should not be allowed. In this paper, we propose biometric based user authentication and one time key generation models. The proposed model is consist of biometric template registration, session key generation and chanel encryption steps. We analyze the difference and benefits of our model with existing CAS models which are made for CATV contents protection, and also provides applications of our model in electronic commerce area.

• Physical Therapy Korea
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• v.15 no.4
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• pp.70-79
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• 2008

The purpose of this study was to find out the effects of electroencephalograph (EEG) power and coherence on cognitive function in normal elderly, non-demented elderly with mild cognitive impairment, and demented elderly during working cognition tasks. Forty elderly women (19 demented elderly, 10 non-demented elderly with mild cognitive impairment, 11 norma1 elderly) participated in this study, All subjects performed working cognition tasks with Raven's CPM while EEG signal was recorded, EEGs were measured continuously at rest and during the working cognition task. EEG power and coherence was computed over 21 channels: right and left frontal, central, parietal, temporal and occipital region. We found that there were more correct answers among normal elderly women than in other groups Owing the working cognition task, ${\Theta}$ wave at Fp1, Fp2 and F8, a wave at Fp2, ${\beta}$ wave at Fp1, Fp2. F4 and F8 of the frontal region was increased significantly in the demented elderly group. On the other hand. ${\Theta}$ wave at Fp1, Fp2 and F7, ${\beta}$ wave at Fp1, Fp2, F3 and F7 of the frontal region was increased significantly in the group of non-demented elderly with mild cognitive impairment. In contrast. in the normal elderly group, all of the ${\Theta}$ wave and ${\beta}$ wave at Fp1, Fp2, F3, F4, F7 and F8 of the frontal region (except ${\beta}$ wave at F3) was increased significantly, These results suggest that the nerves in prefrontal and right hemisphere regions were most active in the demented elderly group during problem solving, and the nerves in the prefrontal and left hemisphere lobe were most active in the group of non-demented elderly with mild cognitive impairment. In contrast, me majority of nerves in the frontal region were active in the normal elderly group.

• Transactions of the Korean hydrogen and new energy society
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• v.10 no.1
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• pp.9-17
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• 1999

The hydriding and dehydriding kinetics were studied for a Mg-25wt.%Ni mixture which has the most excellent hydrogen-storage characteristics among many mechanically-alloyed mixtures. The hydriding and dehydriding rates were measured and the rate-controlling steps were determined by comparing the hydriding and dehydriding rates with the theoretical rate equations. The rate-controlling step in the hydriding reaction is the Knudsen flow and the ordinary gaseous diffusion of hydrogen molecules through interparticle channels, cracks, etc. in the various ranges of weight percentage of absorbed hydrogen $H_a$ below $H_a$=4.0. In the $H_a$ range 4.0 < $H_a{\leq}4.25$, the diffusion of hydrogen atoms through the growing hydride layer is considered the rate-controlling step. The rate-controlling step in the dehydriding reaction is the Knudsen flow and the ordinary gaseous diffusion of hydrogen molecules for all the ranges of weight percentage of desorbed hydrogen $H_d$.

• Journal of Korean Society of Forest Science
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• v.81 no.4
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• pp.346-356
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• 1992

The extensive Snake River floodplain in Northwest United States has experienced major changes in water channels and vegetation types due to floodings. To detect the change of wetland cover-types for the period of 1985 and 1988, post-classification comparison and image differencing change detection techniques were evaluated using Landsat-5 TM digital data. Differenced infrared-band images indicated better accuracy indices than any visible-band images. A thresholding technique was applied to identify the change and no change categories from the transformed images produced by image differencing. The problems in using different accuracy indices, including the Kappa coefficient of agreement, overall accuracy, producer's accuracy, user's accuracy, and average accuracy(based on both the producer's and user's accuracy approaches) in determining an optimal threshold level, were examined.

• Journal of the Korean Society of Costume
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• v.66 no.3
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• pp.75-92
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• 2016

The purpose of this study was to prove how sociocultural perspective of obesity, differences in consumers' perception of body and attitudes of accepting obesity affected individuals' clothing behaviors through cross-cultural studies. The data collected were composed of 612 Korean and US consumers in the 20's and 30's that had experiences in purchasing plus-size products. The results were as follows. First, BMI index was lower in Korean consumers than the US consumers, but Korean consumers received more stress from being overweight compared to the US consumers, and had a more negative attitude about their body. Second, although Korean consumers had lower BMI index and degrees of obesity than US consumers, they were severely stressed by obesity and were found to have a higher level of dissatisfaction with their bodies. Third, Korean consumers responded more sensitively to obesity and had a tendency to display a more negative attitude regarding obesity, and a more passive dependence on clothing. Forth, differences in the body shape were reflected even in wearing evaluation, and US consumers showed a more positive attitude toward evaluations of size suitability and fitness. Fifth, the plus-size market for Korean consumers was still not active, and most products purchased were generic brands obtained from online shopping malls through the Internet. However, in the case of the US, in which the ratio of obese people is high and the plus-size market is growing, consumers were purchasing plus-size brands through various distribution online and offline channels. Sixth, Korean consumers were less satisfied than US consumers with shops, sizes and fitness; however, they were more satisfied with design factors. Finally, it is expected that this study can offer practical implications for marketers and product developers running plus-size market for young obese consumers in their 20 and 30s.

• Journal of the Korean Society of Costume
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• v.66 no.8
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• pp.98-108
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• 2016

Knitwear has been used as an active and functional clothing item due to its flexible and soft nature. Diverse design expressions have made knitwear into an essential fashion item for people today, who are constantly seeking for ways to display their individualism. The purpose of this study is to analyze the actual wearing conditions, and the preferred designs of knitwear for female college students in order to provide a baseline data, which can be used to develop knitwear designs for the subjects of the study. Survey by questionnaire of 135 female college students in 3 universities in Seoul were analysed. The results of the study are as follows: First, the most owned knitwear were sweaters and cardigans. Knitwear was viewed as soft and warm, as well as versatile. It was not restricted to certain sizes, and was comfortable to wear for different activities. Seound, the most preferred items were sweaters and cardigans. The most preferred styles were round neckline sweaters and open V-neckline cardigans. Third, the most preferred designs were plain designs with achromatic colors and wool-blended fabrics. The most preferred images were simple images. The most preferred fit was loose enough for little bit of room inside. Fourth, appropriateness and design of the knitwear were assessed during the purchasing stage. the most preferred method of purchase was purchasing via online stores after researching the knitwear through various channels, such as store visits and the Internet. The preferred price of knitwear was below 100,000 KRW. Fifth, the most common complaints were as follows: changes in the shape and quality of the knitwear after a wash, appearance of nap, and loose threads. In short, it is necessary for female college students to develop high quality knitwear with designs that can display individuality, while being simple.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.2
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• pp.163-172
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• 2003

Boiling heat transfer coefficients and pressure drops for R-22 and R-407C were measured in horizontal micro-channels. The test section is stainless steel tube, inner tube diameters are 1.8mm and 2.8mm, and the respective lengths are 1500mm and 3000mm. The range of mass flux is 300-600kg/$m^2$s and heat flux is 5-15kW/$m^2$. In this results, pressure drop increased linearly for both R-22 and R-407C with increased mass flux, but the increase of heat flux did not affect the pressure. In addition, the pressure drop was fairly increased in the high quality region rather than low quality region. In the range of low quality, the mass flux had a small affect on the heat transfer coefficients, however, in high quality region, the heat transfer coefficients increased even more with increasing mass flux. Under the low quality region and low mass flux, the heat transfer coefficients increased with increasing heat flux densities. The effects of inner tube diameter were clearly observed. Namely, the measured pressure drop inside inner tube diameter 1.8 mm is higher than 2.8 mm with increasing the mass flux and heat flux. Also, the measured local heat transfer coefficient inside inner tube diameter 1.8 mm is higher than 2.8 mm in the range of high qualities. The experimental data for R-407C compared with proposed correlation using pure refrigerant. The experimental data for R-407C was more decreased than the proposed correlation for pure refrigerant up to 50% or more.

• The Korean Journal of Zoology
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• v.28 no.4
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• pp.227-236
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• 1985

In an attempt to make a scrutiny into a mechanism for the formation of quaternary structure of LDH isozymes, male mice were intraperitoneally exposed to a wide range of tetrodotoxin concentration and the changes in relative percentage of the five isozymes were monitored by electrophoresis and subsequent densitometry. The observations that a conspicuous increase of the $H_4$ isozyme was demonstrated in nearly all brain tissues, that the $M_4$ isozyme of skeletal muscle tissue was slightly increased while the $M_3H$ and $M_2H_2$ isozymes were decreased, that the M/H ratio was strikingly reduced in heart tissue and that assembly of $H_4$ isozyme was revealed in liver tissue although its rate was extremely low suggest that new intracellular ionic environment established by compulsory change in Donnan equilibrium could alter the LDH isozyme distribution. The reduction of assembly of $M_3H$ isozyme found in mouse tissues exposed to tetrodotoxin also seems to suggest that the subunit combination of 3M+H is very unfavorable in an intracellular environment deviated from its accustomed one. It was reaffirmed that there might occur TTX-insensitive sodium channels in plasma membrane.