• Research in Mathematical Education
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• v.3 no.2
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• pp.99-112
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• 1999

In this paper, we represent the Piagetian reversible thinking by using the concept of fuzzy complements. In this case the turning point to the reversible thinking can be corre-sponded to the equilibrium points of a fuzzy set, which are shown through some examples. On the other hand, Piaget considered disequilibrium in the theory of equi-libration as a stimulus for students' cognitive structure, furthermore as the driving forces behind intellectual growth. But we suggest a di erent application o Piagetian equi-librium in another point of view as a tool understanding students' psychological stability in problem solving activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.2
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• pp.157-163
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• 1985

Various cell wall polysaccharides and related enzyme activities in hot pepper fruit were determined at different stages of maturity. The uronic acid content of cell walls decreased between immature green and turning stage fruit and then increased by red ripe stage. In contrast, cellulose content of cell walls changed only a little during ripening. Total neutal sugar content of cell wall material decreased 50% and galactose content of the walls decreased about 80% by the turning stage. Polygalacturonase and ${\beta}-galactosidase$ activities, as well as total hemicellulose from isolated cell walls of ripening hot pepper fruit were studied using gel filtration chromatography. Polygalacturonase activity was not detectable but 5 isozymes of ${\beta}-galactosidase$ were resolved. The activities of the enzymes were relatively high and gel filtration showed that they differed in molecular weight. Hemicellulose content decreased during ripening and softening. The molecular weight profiles shifted from high molecular weight to low molecular weight polymers during ripening. The changes in cell walls that may be associated with fruit softening involve the alteration of hemicellulose prior to the degradation of wall-bound uronic acid. It is suggested that the decrease in cell wall galactose involved changes in turnover of new cell wall components.

• Journal of Microbiology
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• v.45 no.2
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• pp.122-127
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• 2007

Factors indicating culture status of two Spirulina platensis strains were monitored in a batch mode cultivation for 36 days. Changing mode in all factors showed a common turning point, indicating shift of cell or culture status. Mean biomass productivity was highly sustained until day 22, chlorophyll a concentration peaked on day 22, pH value was > 12 on day 22, coil number was abruptly shortened on day 22, and floating activity was sustained at greater than 79% after day 22, indicating that day 22 is a criterion reflecting phase-transfer in cell physiology in a batch culture system. Many of these changes may have been caused by increased pH, suggesting that pH control is essential for mass production of S. platensis. Fluctuations in floating activity were likely induced by the number of cellular gas vacuoles. Consequently, coil number per trichome and floating activity of S. platensis could readily act as simple indicators for determination of culture status or harvesting time of cells.

• Journal of Agricultural Extension & Community Development
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• v.9 no.1
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• pp.121-130
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• 2002

Youth will undergo many turning points in their times, and get opportunities to promote their physical, cognitive, social and affective development by participating in various programs. The purpose of this study were to analyze the farming 4-H club member's participation in camping activity and suggest the improving directions for camping programs. This research was carried out by review of literature and survey. The data were collected from 170 youth who participated in the 4-H camping activity in 2002. The major findings of the study were as follows; 1) The prior learning for camping activity affected the level of youth's camping satisfaction. 2) The rural youth expected that the camp fire and recreation program should be further improved. 3) To bring more youth's participation in the camping, time and place should be taken into consideration. 4) The 4-H members who decided to participate in the camping for themselves showed higher satisfaction.

• The Korean Journal of Pharmacology
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• v.10 no.1 s.15
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• pp.11-19
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• 1974

To see if the treatments of d-amphetamine and chlorpromazine have any influence upon the orienting response and general behavioral activity, 3 groups of male Holtzman rats were prepared, namely d-amphetamine animals (1.0 mg/kg.i.p.), chlorpromazine rats (1.0 mg/kg.i.p.) and the physiological saline control animals. The general behavioral activity was examined by visual scanning using the time-sample method in the adaptation period of orienting response. The occurence of orienting response and its rate of habituation were evaluated by observing cessation of ongoing activity in response to a sound stimulus (1,000 Hz, 70 db & 0.1 sec), or turning of head toward the source of stimulus in 20 trials. Attention shift from sound to light stimulus was also tested in 10 trials. The results obtained were as follows; 1. The general behavioral activity of d-amphetamine group was significantly greater than that of control, however, the chlorpromazine animals showed the tendency to decrease in activity. 2. The d-amphetamine group showed the occurence of orienting response to sound significantly more often than that of placebo controls. However, the chlorpromazine group exhibited significantly fewer orienting response than the placebo group did. 3. The d-amphetamine group displayed no clear out habituation to the orienting response following the repetition of trials, though the placebo and the chlorpromazine groups demonstrated apparent habituation to the response. 4. The three animal groups did not differ significantly from each other with regard to shift of attention from sound to light stimulus. It is inferred that the d-amphetamine tends to increase general activity has a definite facilitative action of orienting response and a inhibitory influence upon the habituation of the latter response. On the contrary, the chlorpromazine tends to decrease general activity, has a inhibitory action of orienting response and facilitatory action of habituation of the response.

• Journal of the Korean Applied Science and Technology
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• v.39 no.4
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• pp.507-516
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• 2022

The purpose of this study was to investigate the effect of rotational preference on body stability based on COP and EMG analysis in an quiet standing after turn in the left and right directions. The subjects of this study were 16 subjects with a high lateral preference for the right hand and foot. The subjects of this study were 16 subjects with high unilateral preference for the right hand and foot, and three rotational direction conditions (QS: quiet standing, LT: 10 turns on the left, RT: 10 turns on the right) were performed. In order to evaluate the stability in an quiet standing after turning, the results were derived and analyzed using a COP plate and an EMG. As a result of the study, LT and RT were larger than QS for all COP variables, but there was no difference according to the direction of turning. In EMG, RT showed larger muscle activity than the QS according to the rotational direction in left and right gastrocnemius. In conclusion, although all subjects had a high right lateral preference, there was no effect of rotational preference in COP, and gastrocnemius showed the effect of rotational preference.

• The korean journal of orthodontics
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• v.49 no.4
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• pp.254-264
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• 2019

Objective: To evaluate the short-term changes in masticatory muscle activity and mandibular movement patterns after orthognathic surgery in skeletal Class III patients with facial asymmetry. Methods: Twenty-seven skeletal Class III adult patients were divided into two groups based on the degree of facial asymmetry: the experimental group (n = 17 [11 male and 6 female]; menton deviation ${\geq}4mm$) and control group (n = 10 [4 male and 6 female]; menton deviation < 1.6 mm). Cephalography, electromyography (EMG) for the anterior temporalis (TA) and masseter muscles (MM), and mandibular movement (range of motion [ROM] and average chewing pattern [ACP]) were evaluated before (T0) and 7 to 8 months (T1) after the surgery. Results: There were no significant postoperative changes in the EMG potentials of the TA and MM in both groups, except in the anterior cotton roll biting test, in which the masticatory muscle activity had changed into an MM-dominant pattern postoperatively in both groups. In the experimental group, the amount of maximum opening, protrusion, and lateral excursion to the non-deviated side were significantly decreased. The turning point tended to be shorter and significantly moved medially during chewing in the non-deviated side in the experimental group. Conclusions: In skeletal Class III patients with facial asymmetry, the EMG activity characteristics recovered to presurgical levels within 7 to 8 months after the surgery. Correction of the asymmetry caused limitation in jaw movement in terms of both ROM and ACP on the non-deviated side.

• Journal of Sensor Science and Technology
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• v.15 no.2
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• pp.97-101
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• 2006

Silver electrode having a high Electrocatalytic activity is oxygen-permeable electrode, in which oxygen ad-atoms are adsorbed and moved toward YSZ electrolyte by bulk diffusion. It is the different point in comparison to usual porous electrodes, especially platinum, which react with oxygen only in TPBs(Three Phase Boundaries). Also ad-atoms at TPBs of Pt are diffused to YSZ electrolyte by interfacial diffusion mechanism. These properties were used for turning down the operating temperature of YSZ from over $600^{\circ}C$ to below $450^{\circ}C$. The different heat-treatment temperature between a working electrode and a reference electrode suppresses the formation of silver oxides and reduces a volatility of Ag as well. Above all, these own characteristics and special processes of Ag improved a long-term stability of a oxygen sensor.

• Special Issue of the Society of Naval Architects of Korea
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• 2008.09a
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• pp.62-67
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• 2008

The hovercraft is the amphibious hovercraft. Design and manufacturing companies of the aero propeller exist rarely in the world. Hence the propeller has beef designed and manufactured by manufacturing companies which make aero propeller mainly. In this paper, the hovercraft propeller of similar, which is building and designing by HHIC, is considered the type of aero propeller, rotational speed, diameter, number of blades, Open air propeller efficiency. As the result of check, hovercraft which is necessary huge static thrust is needed the ducted propeller in order to improve climbing capacity. However, the number of blades and turning direction almost do not affect.

• Proceedings of the Korean Biophysical Society Conference
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• 1997.07a
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• pp.24-24
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• 1997

We have investigated whether NO affects the activities of the rat brain Maxi- K channels reconstituted into the lipid bilayer. In order to introduce NO, we utilized an antibiotic, streptozotocin (STZ), which releases NO upon illumination. While adding STZ itself did not affect the channel activity, turning on the light in the presence of STZ induced an increase in the open probability (Po) of the channel.(omitted)