• Bulletin of the Korean Chemical Society
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• v.24 no.1
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• pp.49-54
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• 2003

TiO₂nanoparticles were synthesized using the metallorganic chemical vapor deposition process. Particles with and without metal ion dopants were obtained. X-ray photoelectron and energy dispersive X-ray spectroscopic measurements confirmed the stoichiometry of the TiO₂nanoparticles. X-ray diffraction patterns showed a polycrystalline anatase structure of TiO₂. Transmission electron microscopy revealed that these particles are of nanoscale dimensions. Exact particle size and size distribution analyses were carried out by dynamic light scattering. The average particle size was determined to be 22 nm. The nanosize particles provided large surface area for photocatalysis and a large number of free surface-charge carriers, which are crucial for the enhancement of photocatalytic activity. To improve the photocatalytic activity, metal ions, including transition metal ions $(Pd^{2+},\;Pt^{4+},\;Fe^{3+})$ and lanthanide ion $(Nd^{3+})$ were added to pure TiO₂nanoparticles. The effects of dopants on photocatalytic kinetics were investigated by the degradation of 2-chlorophenol under an ultraviolet light source. The results showed that the TiO₂nanoparticles with the metal ion dopants have higher photocatalytic activity than undoped TiO₂. The $Nd^{3+}$ ion of these dopant metal ions showed the highest catalytic activity. The difference in the photocatalytic activity with different dopants is related to the different ionic radii of the dopants.

• Journal of the Korea Convergence Society
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• v.10 no.3
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• pp.149-155
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• 2019

In this study, the multiplicity of synchronous online class discussion activity is explored at conceptual level. From the cultural-historical activity theory (CHAT), each utterance may be considered as a product of the activity system. Alderfer's ERG theory is employed as another theoretical framework for the study. Based on the subject's existence, relationship, growth needs, their class discussion activities constitute four different dimensions: physical/biological, cultural/institutional, social/relational, and cooperative knowledge construction. It is inherent in individual activities and has a different arrangement according to their interests and situations, and at the same time acts as a factor of cooperation and competition among the participants. Through this, collective discussion activities represent complex and dynamic development patterns.

• Korean Journal of Health Education and Promotion
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• v.28 no.1
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• pp.93-101
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• 2011

Objectives: The aim of this study was to investigate the prevalence of metabolically obese, normal-weight (MONW) phenotype and the association between lifestyle factors and the risk of MONW in Korean adolescents. Methods: Normal-weight (BMI, 5th to 85th percentile) subjects with ${\geq}1$ metabolic abnormalities were categorized as MONW phenotype. Data from adolescents aged 12 to 18 years who have participated in the Korean National Health and Nutrition Examination Survey in 1998 (n=751) and 2008 (n=455) were analyzed. Physical activity and dietary intakes were assessed. Results: The prevalence of hypertension and hyperglycemia in 2008 decreased compared with that in 1998 (P<0.001) but the prevalence of abdominal obesity, hypertriglyceridemia and low HDL did not changed. The overall prevalence of MONW in Korean adolescents declined over 10 years (P<0.001). Adolescent boys and girls engaging regular exercise significantly increased over 10 years (P<0.01). Physically active adolescents had a lower risk of being MONW in 1998. Dietary intake patterns were not associated with a risk of MONW. Conclusions: The prevalence of MONW among Korean adolescents declined over 10 years which may be due to the decreased prevalence of hypertension and hyperglycemia. The risk of MONW would be lower in individuals who are physically active.

• The Journal of Korean Physical Therapy
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• v.22 no.4
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• pp.97-101
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• 2010

Purpose: Sensory input is very important for proper performance of human. Two-point discrimination is the most widely used tactile sensory test. The purpose of this study was to find the changes in cortical activation patterns between tactile stimulation and two-point discrimination. Methods: Two healthy subjects participated in our study. fMRI scanning was done during 4 repeated blocks of tactile stimulation and two point discrimination of the right index finger tip. In one block, stimuli were repeated 10 times every three seconds. To determine the changes of cortical neurons during sensory input, intensity index was analyzed. Results: When tactile stimulation of the right index finger tip was completed, only contralateral primary somatosensory area was activated. In contrast, during two-point discrimination, both the primary somatosensory area and ipsilateral supplementary sensory area were activated. Conclusion: During two point discrimination, both primary somatosensory area and ipsilateral supplementary sensory area were activated. Therefore, two-point discrimination is required more complex and conscious activity than tactile stimulation.

• The Journal of Korean Physical Therapy
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• v.32 no.2
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• pp.75-79
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• 2020

Purpose: This study analyzed the immediate effects of intra-abdominal pressure with visual feedback on the muscle activation of the upper trapezius and sternomastoid during natural inspiration and forced inspiration in individuals with costal respiration. Methods: The eighteen individuals with upper costal breathing pattern participated in this study. Surface electromyography was used to analyze the muscle activity of the upper trapezius and sternomastoid during natural inspiration and forced inspiration before and after intra-abdominal pressure. Results: A significant difference in muscle activation was observed with the muscle type, inspiration type, and test session (p<0.05). The muscle activities of the sternomastoid and upper trapezius decreased significantly during forced inspiration after intra-abdominal pressure training (p<0.05). On the other hand, there was no significant difference during natural inspiration in both muscles (p>0.05). A comparison of the difference between the pre-test and post-test during forced inspiration revealed the upper trapezius to be significantly larger than the sternomastoid (p<0.05). No significant difference was noted during natural inspiration (p>0.05). Conclusion: The intra-abdominal pressure has positive effects on correcting the breathing patterns in individuals with costal respiration.

• Journal of International Academy of Physical Therapy Research
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• v.10 no.4
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• pp.1873-1878
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• 2019

Background: Walking is a complex activity. The main components of walking include balance, coordination, and symmetrical posture. The characteristics of walking patterns of stroke patients include slow walking, measured by gait cycle and walking speed. This is an important factor that reflects post-stroke quality of life and walking ability. Objective: This study aimed to examine the effect of deep lumbar muscle stabilization exercise on the spatiotemporal walking ability of stroke patients. Design: Quasi-experial study Methods: The experiment was conducted 5 times per week for 4 weeks, with 30 minutes per session, on 10 subjects in the experimental group who performed the deep lumbar muscle stabilization exercise and 10 subjects in the control group who performed a regular exercise. Variables that represent the spatiotemporal walking ability (step length, stride length, step rate, and walking speed) were measured using GAITRrite before and after the experiment and were analyzed. Results: There was a significant difference in the pre- and post-exercise spatiotemporal walking ability between the two groups (p<.05). Furthermore, there was a significant difference in the step rate and walking speed between the two groups (p<.05). Conclusions: Deep lumbar muscle stabilization exercise is effective in improving the walking ability of stroke patients. Therefore, its application will help improve the spatiotemporal walking ability of stroke patients.

• Physical Therapy Rehabilitation Science
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• v.13 no.2
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• pp.213-222
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• 2024

Objective: Stroke is a leading cause of disability worldwide, often leaving survivors with significant cognitive and motor impairments. Dual-task (DT), which involves performing cognitive and motor tasks simultaneously, can influence brain activation patterns and functional recovery in stroke patients. Design: A systematic review Methods: Following PRISMA guidelines, databases including MEDLINE, CINAHL, Embase, and Web of Science were searched for studies assessing cortical activation via functional near-infrared spectroscopy (fNIRS) during DT performance in stroke patients. Studies were selected based on predefined eligibility criteria, focusing on changes in hemodynamic responses and their correlation with task performance. Results: Eight studies met the inclusion criteria. Findings indicate that DT leads to increased activation in the prefrontal cortex (PFC), premotor cortex (PMC), and posterior parietal cortex (PPC), suggesting an integrated cortical response to managing concurrent cognitive and motor demands. However, increased activation did not consistently translate to improved functional outcomes, highlighting the complex relationship between brain activation and rehabilitation success. Conclusions: DT interventions may enhance cortical activation and neuroplasticity in post-stroke patients, but the relationship between increased brain activity and functional recovery remains complex and requires further investigation. Tailored DT programs that consider individual neurophysiological and functional capacities are recommended to optimize rehabilitation outcomes.

• International Journal of Internet, Broadcasting and Communication
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• v.15 no.4
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• pp.294-303
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• 2023

This study was to find out the differences in self-esteem, body composition, and muscle strength of middle-aged women, and nine physical labor groups were selected as beautification workers at D University in Cheonan, and a total of 17 were selected as non-physical labor groups were 8 full-time housewives living in Cheonan. After selecting the subjects, the subjects arrived 30 minutes before the start of the experiment and completed the self-esteem questionnaire. After taking the stability, the measurement was carried out in the order of body composition, grip strength, and isokinetic muscle function, and the independent sample t-test was conducted. First, middle-aged women's self-esteem according to the type of physical labor was high in the physical labor group in relation to others among the sub-factors. Second, there was no significant difference in body composition according to the physical labor patterns of middle-aged women. Third, there was no significant difference in lower limb isokinetic muscular strength according to the types of physical labor of middle-aged women. Third, there was no significant difference in lower limb isokinetic muscular strength according to the types of physical labor of middle-aged women. The self-esteem according to physical labor is caused by the sense of belonging in the workplace, and the difference between body composition and muscular strength is insignificant. Therefore, it is necessary to introduce a physical activity program to promote self-esteem due to aging and prevent physical deterioration regardless of occupation.

• Korean Institute of Interior Design Journal
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• no.15
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• pp.62-68
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• 1998

Children develop in direct relation and response to their physical environment, The purposes of this study were to investigate the current interior design conditions of classrooms in kindergarten and to provide interior planning guidelines for children's behavioral and developmental improvement and better educational environment. Data were collected through interview and questionnaire survey. The sample included 239 teachers who were employed in 23 kindergartens located in Pusan. The data were analyzed by using SPSS-PC. The major findings were as follows; (1) Wood and wallpapers which provide various colors and patterns are recommendable as a classroom finish rather than paint which looks monotonous. (2) Teachers preferred 7 or 8 activity centers in classroom and furniture or partition is the best when dividing space. (3) Classroom should be large enough to locate various types of furniture that designed based on child-size and objects to store. (4) Activity centers should be lit by different types of task lighting such as floor lamp and backer to provide sufficient level of light.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.32 no.3
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• pp.78-84
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• 2009

The purpose of this study was to compare gait patterns during pregnancy. Because of the changes in hormone levels and anatomical changes such as body mass, body-mass distribution, joint laxity, and musculotendinous strength that result from pregnancy, it was possible that there would be certain gait deviations associated with these changes. Three-dimensional gait analyses were performed from a self-selected pace, and six subjects(height : $163{\pm}5.3cm$, mass : $61.3{\pm}3.80kg$, $65.3{\pm}5.14kg$, $70.2{\pm}4.98kg$) participated in the three times(the early, middle and last years). 7 cameras(Proreflex MCU-240, Qualisys) and 2 force plates (Type 9286AA, Kistler) were used to acquire raw data. The parameters were calculated and analyzed with Visual-3D and Joint moments computed using inverse dynamics. In conclusion, pregnant women's gait patterns were changed during pregnancy period because pregnancy makes them physical changes. The main changes were joint moments and kinematic factors during pregnancy period. The pregnancy transformed normal gait pattern Into toe out position. Therefore, exercise programs to improve muscle activity were necessary where joint moments were small. The development of simulator should be studied for pregnant women's tailored shoes and accessories in future.