• 한국연소학회:학술대회논문집
• /
• 2012.11a
• /
• pp.351-354
• /
• 2012

The characteristics of flame dynamics occurring near bluff body was experimentally investigated in a model combustor with V-gutter bluff body. Flashback occurs due to the change of pressure gradient in the combustor, and flashback distance depends on equivalent ratio. Unstable flames can be classified into three types depending on the flashback distance and structure. Re-stabilization takes place as the flame moves downstream. This process is supported by a strong vortex structure behind bluff body.

• Journal of Korean Physical Therapy Science
• /
• v.16 no.4
• /
• pp.39-47
• /
• 2009

Background: To evaluate the effects of Australian stabilization exercise for chronic low back pain. Methods: Interventions consisted of exercises aimed at recovery of Multifidus in cocontraction with Transverse abdominis through neural control retraining. Results: After exercise, there were significant improvement(p<.05) in pain and disability score. Conclusions: Neural control stabilization exercise can be effective intervention for chronic Low Back Pain patients.

• Journal of the Korean Society of Physical Medicine
• /
• v.7 no.3
• /
• pp.309-318
• /
• 2012

Purpose : The purpose of this study was to compare 2 different interventions, global postural re-education (GPR) and specific spinal stabilization exercise in the healthy elderly of women. Methods : A total of 28 subjects were randomized into 2 treatment groups: GPR, where therapy involved muscle global chain stretching, or specific spinal stabilization exercise with conventional static stretching (GPR group: n=14, specific spinal stabilization exercise group: n=14). Both groups received exercise intervention 3 times a week for 12-weeks. Results : Outcome was based on trunk endurance, trunk flexibility, Pressure Bio Feedback, Oswestry Disability Index measured immediately before and after intervention. Trunk flexibility, Pressure Bio Feedback, Oswestry Disability Index improved more in GPR group after intervention. There were no differences between the 2 exercise approaches for any of the trunk endurance. Conclusion : As the above results, GPR appear to improve Trunk flexibility, Pressure Bio Feedback, Oswestry Disability Index to the elderly of women. The efficacy of the GPR program used in this study should be further investigated in a long period study and objective outcomes.

• Clean Technology
• /
• v.22 no.4
• /
• pp.299-307
• /
• 2016

These days, coal is one of the most important energy resources used for transportation, industry, and electricity. There are two types of coal: high-rank and low-rank. Low-rank coal has a low calorific value and contains large amounts of useless moisture. The quality of low-rank coal can be increased by simple drying technology and it needs to be stabilized by hydrocarbons (e.g. palm acid oil, PAO) to prevent spontaneous combustion and moisture re-adsorption. Spontaneous combustion becomes a major problem during coal mining, storage, and transportation. It can involve the loss of life, property, and economic value; reduce the quality of the coal; and increase greenhouse gas emissions. Besides spontaneous combustion, moisture re-adsorption also leads to a decrease in quality of the coal due to its lower heating value. In this work, PAO was used for additive to stabilize the upgraded coal. The objectives of the experiments were to determine the stabilization characteristic of coal by analyzing the behavior of upgraded coal by drying and PAO addition regarding crossing-point temperature of coal, the moisture behavior of briquette coal, and thermal decomposition behavior of coal.

• The Journal of Korean Physical Therapy
• /
• v.29 no.4
• /
• pp.181-186
• /
• 2017

Purpose: The paper presents an intervention for clinical applications in the future by examining the effects of 3D stabilization exercise on patients with lumbar instability, which causes problems in the muscles and balance, and analyzing the effects of balanced lumbar muscles on the static balance. Methods: After collecting samples randomly from thirty patients with lumbar instability, fifteen patients selected for 3D stabilization exercise were placed in the stability group and fifteen patients selected for Swiss ball exercise were placed in the ball exercise group. The intervention program was applied for thirty minutes a session, once a day, three days a week for four weeks. Before the intervention, the lumbar muscle activity and static balance were measured. After four weeks, they were re-measured in the same way and the data were analyzed. Results: In relation to the within-group changes in muscle activity, all groups except for the LEO and REO groups showed significant differences. Regarding the between-group changes in muscle activity depending on the left and right difference, ES, RA, and TrA but not EO showed significant differences. In addition, there were significant differences in the between-group change in static balance. Conclusion: 3D stabilization exercise improves the muscle activity by promoting a balanced posture of lumbar muscles and changing senses, such as a proprioceptor but this had a positive influence on the static balance by controlling the balance of muscles.

• Journal of the Korean Society of Physical Medicine
• /
• v.8 no.1
• /
• pp.29-39
• /
• 2013

PURPOSE: The purpose of this study was to determine if the program focusing on gluteal muscle exercise combined lumbar stabilization had an effects on pain, functional disability and lumbar instability in chronic low back pain patients who had lumbar instability. METHODS: Thirty four patients were recruited in this study. The participants were randomly allocated stabilization exercise group (SEG) (n=17) and gluteal muscle exercise group (GEG) (n=17). The gluteal muscle exercise group conducted gluteal muscle exercises combined lumbar stabilization and stabilization exercise group did only lumbar stabilization exercise for 30 minutes three times a week for six weeks. Pre-exercise assessment tools, visual analogue scale (VAS) and Korean version Oswestry Disability Index level (KODI) were used for pain and functional disability each. Also, these were scored by the tool of lumbar instability. The pain, functional disability levels, and lumbar instability after six weeks with this exercise were re-evaluated. RESULTS: First, SEG showed a significant decrease in the lumbar pain, functional disability levels and lumbar instability. Second, GEG showed a significant decrease in the lumbar pain, functional disability levels and lumbar instability. The third, GEG showed even more significant decrease in the lumbar pain levels, functional disability levels and lumbar instability than SEG. CONCLUSION: Gluteal muscle exercises combined lumbar stabilization are more effective than only lumbar stabilization exercise in the pain levels, functional disability levels and lumbar instability for the chronic low back pain patients with lumbar instability.

• Bulletin of the Korean Chemical Society
• /
• v.31 no.1
• /
• pp.174-176
• /
• 2010

• Journal of the Korean Society of Combustion
• /
• v.15 no.3
• /
• pp.1-7
• /
• 2010

Edge flames have been interested as a basic structure that is concerned to flame stabilization and re-ignition of non-premixed flames. The edge flame consists of a lean premixed flame, a rich premixed flame, and a diffusion flame. In order to investigate fundamental structures of the edge flames at the conditions near the flammability limits, edge flames were stabilized within a heated narrow channel. Highly diluted partially premixed methane was used, and the flow rates of air and the partially premixed mixture were controlled. Various flame behaviors, including a transition between ordinary edge flames and premixed flames, were observed. Flame stabilization characteristics were examined as well. All flame stabilization conditions in this study showed a similar trend: characteristic time scales were inversely proportional to the equivalence ratio defined at the burner inlet. Finally, an interesting flame structure having a weak diffusion branch enveloped by a closed premixed branch was found near the flammability limits even in a fuel-air mixing layer. This structure was named as a "flame-drop" and the importance of this structure was first suggested.

• BMB Reports
• /
• v.37 no.5
• /
• pp.533-537
• /
• 2004

Previously published kinetic data on the interactions of seventeen different enzymes with their physiological substrates are re-examined in order to understand the connection between ground state binding energy and transition state stabilization of the enzyme-catalyzed reactions. When the substrate ground state binding energies are normalized by the substrate molar volumes, binding of the substrate to the enzyme active site may be thought of as an energy concentration interaction; that is, binding of the substrate ground state brings in a certain concentration of energy. When kinetic data of the enzyme/substrate interactions are analyzed from this point of view, the following relationships are discovered: 1) smaller substrates possess more binding energy concentrations than do larger substrates with the effect dropping off exponentially, 2) larger enzymes (relative to substrate size) bind both the ground and transition states more tightly than smaller enzymes, and 3) high substrate ground state binding energy concentration is associated with greater reaction transition state stabilization. It is proposed that these observations are inconsistent with the conventional (Haldane) view of enzyme catalysis and are better reconciled with the shifting specificity model for enzyme catalysis.

• Journal of the Korean Society of Combustion
• /
• v.20 no.4
• /
• pp.19-25
• /
• 2015

An experimental study was conducted to find the effect of a pilot flame on the flammability of inert-gas-diluted methane and propane. The diffusion pilot flame was formed with propane at the innermost nozzle of a concentric triple co-flow burner. The main diffusion flame was formed with nitrogen-diluted methane or propane at the outermost nozzle of the burner. An air flow was located in-between. The results showed that the existence of the pilot flame helped stabilizing the main flame even at the flammability limit concentration of nitrogen-diluted fuel. The co-flow burner generated re-circulation zones and local variation of equivalence ratio depending on the flow rates of the reactants, which are known to help flame stabilization. Hot-wire experiments confirmed that both heating of the reactants and supplying of active chemical species by the pilot flame contributed to stabilization of the main flame. The results of this study would suggest a design concept for an efficient SVRU system that minimizes the emission of unburned hydrocarbon fuel from ship fuel tanks.