• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.8
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• pp.1122-1133
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• 2003

Numerical characteristics of implicit upwind schemes, such as upwind ADI, line Gauss-Seidel (LGS) and point Gauss-Seidel (LU) algorithms, for Navier-Stokes equations have been investigated. Time-derivative preconditioning method was applied for efficient convergence at low Mach/Reynolds number regime as well as at large grid aspect ratios. All the algorithms were expressed in approximate factorization form and von Neumann stability analysis was performed to identify stability characteristics of the above algorithms in the presence of high grid aspect ratios. Stability analysis showed that for high aspect ratio computations, the ADI and LGS algorithms showed efficient damping effect up to moderate aspect ratio if we adopt viscous preconditioning based on min-CFL/max-VNN time-step definition. The LU algorithm, on the other hand, showed serious deterioration in stability characteristics as the grid aspect ratio increases. Computations for several practical applications also verified these results.

• Mycobiology
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• v.33 no.1
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• pp.41-50
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• 2005

Results from an innovative approach to improve remediation in the rhizosphere by encouraging healthy plant growth and thus enhancing microbial activity are reported. The effect of arbuscular mycorrhizal fungi (Am) on remediation efficacy of wheat, mungbean and eggplant grown in soil spiked with polyaromatic hydrocarbons (PAH) was assessed in a pot experiment. The results of this study showed that Am inoculation enhanced dissipation amount of PAHs in planted soil, plant uptake PAHs, dissipation amount of PAHs in planted versus unplanted spiked soil and loss of PAHs by the plant-promoted biodegradation. A number of parameters were monitored including plant shoot and root dry weight, plant tissue water content, plant chlorophyll, root lipid content, oxido-reductase enzyme activities in plant and soil rhizosphere and total microbial count in the rhizospheric soil. The observed physiological data indicate that plant growth and tolerance increased with Am, but reduced by PAH. This was reflected by levels of mycorrhizal root colonization which were higher for mungbean, moderate for wheat and low for eggplant. Levels of Am colonization increased on mungbean > wheat > eggplant. This is consistent with the efficacy of plant in dissipation of PAHs in spiked soil. Highly significant positive correlations were shown between of arbuscular formation in root segments (A)) and plant water content, root lipids, peroxidase, catalase polyphenol oxidase and total microbial count in soil rhizosphere as well as PAH dissipation in spiked soil. As consequence of the treatment with Am, the plants provide a greater sink for the contaminants since they are better able to survive and grow.

• Journal of muscle and joint health
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• v.13 no.1
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• pp.7-19
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• 2006

Falls are a major sources of death and injury in elderly people. Aged-related changes in the physiological systems which contribute to the maintenance of balance are well documented in older adults. These changes coupled with age-related changes in muscle and bone are likely to contribute to an increased risk of falls in this population. Regular exercise may be one way of preventing falls and fall-related fractures. However, the optimal exercise prescription to prevent falls has not yet been defined. On the literature review of exercise intervention for fall prevention in the elderly, exercise appeared to be a useful tool in fall prevention by improving fall risk factors. The optimum exercise prescription; moderate intensity frequency of 3-4 times per week, duration of 30-60minutes can contribute to decreased hazards and number of fall. Fall prevention protocol should include safety, falling effect, enjoyment, and easiness to follow for older people. Effective exercise programs suggested for fall prevention were such as weight-bearing exercise, resistance exercise, lower muscle strength with elastic band, swiss ball exercise walking, tai chi, and yoga.

• Journal of The Korean Society of Grassland and Forage Science
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• v.11 no.4
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• pp.215-221
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• 1991

This experiment was carried out to determine the effects of cutting frequency and nitrogen fertilization in the mixed pasture on root production and its depth distribution. The results are summarized as follows: 1. Root distribution studied on botanical composition was not significantly different by the upper 20cm level in all treatments. 2. Root yields were all high irrespectively of dominant species. However, Arrhenatherum elatius dominant pasture showed the lowest. Alopecurus pratensis dominant pasture showed the highest in root yield. 3. With the root yield, there was no significant difference in cutting frequency, but the moderate nitrogen level(N-2) showed the highest root yield among three N levels. 4. The depth distribution of root was 1m depth in all treatments.

• Journal of Korean Dental Science
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• v.2 no.1
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• pp.11-18
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• 2009

The purpose of this study was to investigate the possibility to reduce the toxicity of oil based root canal sealers containing calcium hydroxide using MTT & agar overlay assays. Thus some formulations of traditional root canal sealers were replaced with oil-soluble solvents and experimental root canal sealers manufactured. In MTT assay, Cell viability of all experimental sealers in addition with oil soluble solvents were observed significantly higher than both control groups, especially according to replace zinc and/or calcium ion components. Also agar overlay assay was appeared moderate to no cell responses into modifying both zinc and/or calcium ion components and oil soluble solvent weight. Authors found the reducing effect of cell toxicity through significant role of oil soluble solvent factor into root canal sealer containing calcium hydroxide.

• Journal of Acupuncture Research
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• v.30 no.5
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• pp.219-226
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• 2013

Objectives : The purpose of this study is to report the effect of Korean medicine treatment on a patient with brachial plexus injury. Methods : The patient with symptoms of pain and dysesthesia on right forearm and hand was treated with acupuncture treatment, herbal medicine, moxibustion and physical treatment. Improvement of the patient's symptoms was evaluated by Hepatic dullness sound, NRS, VAS, SF-36 bodily pain, grip strength. Results : After 42 days of treatment, NRS score significantly decreased. VAS score, SF-36 bodily pain and grip strength showed moderate improvement. Conclusions : This results suggest that Korean medicine treatment may be effective in reducing the symptoms of brachial plexus injury.

• Journal of Korean Academy of Nursing
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• v.44 no.4
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• pp.446-457
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• 2014

Purpose: This study was done to evaluate the effects of psychosocial interventions on cortisol and immune response in adult patients with cancer. Methods: MEDLINE via PubMed, Cochrane Library CENTRAL, EMBASE, CINAHL and domestic electronic databases were searched. Twenty controlled trials (11 randomized and 9 non-randomized trials) met the inclusion criteria with a total of 862 participants. Methodological quality was assessed using the Cochrane's Risk of Bias for randomized studies and the Risk of Bias Assessment tool for non randomized studies. Data were analyzed using the RevMan 5.2.11 program of Cochrane library. Results: Overall, study quality was moderate to high. The weighted average effect size across studies was -0.32 (95% CI [-0.56, -0.07], p=.010, $I^2 $=45%) for cortisol concentration, -0.62 (95%CI [-0.96,-0.29], p<.001, $I^2 $=0%) for T lymphocyte (CD3) and -0.45 (95%CI [-0.74, -0.16], p=.003, $I^2 $=0%) for Th lymphocyte (CD4) numbers. Psychosocial interventions were not effective for Tc lymphocyte (CD4), NK cell, monocyte, and cytokine response. Conclusion: Although these results provide only small evidence of successful immune modulation, they support the conclusion that psychosocial interventions can assist cancer patients in reducing emotional distress and improving immune response.

• Journal of Korean Academy of Nursing
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• v.43 no.5
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• pp.658-668
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• 2013

Purpose: The purpose of this study was to investigate the effects of psychosocial interventions on pain in cancer patients. Methods: Eight studies published between 1980 and 2012 in Korean and ten studies published between 2002 and 2012 in English met the inclusion criteria with a total of 1539 participants. Methodological quality assessed by Cochrane's Risk of Bias for randomized studies and Risk of Bias Assessment tool for non randomized studies. The data were analyzed by the RevMan 5.2 program of Cochrane library. Results: Overall, study quality was moderate to high. Effect sizes were heterogeneous and subgroup analysis was done. Cognitive behavioral therapy (CBT) were effective for pain (ES= -0.35; 95% CI= -0.56, -0.13). Pain education studies measured with NRS and VAS were effective for pain (ES= -0.77; 95% CI= -1.01, -0.52). Publication bias was not detected. Conclusion: This study support the use of psychosocial interventions administered to cancer patients for their pain management. However, more well-designed studies are needed.

• Journal of Oral Medicine and Pain
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• v.13 no.1
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• pp.5-12
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• 1988

The purpose of this study was to evaluate the therapeutic effect of occlusal stabilization splint on the clinical symptoms and the condylar movement in patients with Temporomandibular Disorders(TMD). For the study, 15 TMD patients treated with stabilization splint and followed up were selected. The age of them was from 18 to 65 years and the mean period of treatment was 2.9 months. The author examined signs and symptoms of TMD according to Dr. Friction's evaluation from and recorded the condylar paths with Denar pantronic before and after splint therapy. The obtained results were as follows : 1. On the first visit, 11 patients(73.3%) showed muscle tenderness on palpation and the frequency was lateral pterygoid, masseter, medial pterygoid, temporalis, sternocleidomastoideus in the order named. 2. Occlusal stabilization splint was more effective in pain relief(100%) than in other dysfunction improvement(85.7%) 3. The amount of maximum opening increased from 37.1㎜ to 42.2㎜, but those of protrusion and laterotrusion changed little. 4. Pan. PRI scores decreased from 32.9 to 21.8, which meant improved reproducibility of mandibular border movements, and the group with sever dysfunction category showed more decrease in score than the group with moderate or slight dysfunction category.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.404-409
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• 2004

To maximize the productivity in machining molds and dies, machine tools should operate at high speeds. During the high speed operation of moving frames or spindles, vibration problems are apt to occur if the machine tool structures are made of conventional steel materials with inferior damping characteristics. However, self-excited vibration or chatter is bound to occur during high speed machining when cutting speed exceeds the stability limit of machine tool. Chatter is undesirable because of its adverse effect on surface finish, machining accuracy, and tool life. Furthermore, chatter is a major cause of reducing production rate because, if no remedy can be found, metal removal rates have to be lowered until vibration-free performances is obtained. Also, the resonant vibration of machine tools frequently occurs when operating frequency approaches one of their natural frequencies because machine tools have several natural frequencies due to their many continuous structural elements. However, these vibration problems are closely related to damping characteristics of machine tool structures. The polymer concrete has high potential for machine tool bed due to its good damping characteristics with moderate stiffness. This paper presents the use of polymer concrete and sandwich structures to overcome vibration problems. Also, co-cure bonding method for functional part mounting was exhibited experimentally, by which manufacturing time and cost for polymer concrete bed will be remarkably reduced.