• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.379-381
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• 2014

Influence of fuel concentration gradient was investigated near flame extinction limit in buoyancy-suppressed non-premixed counterflow flame with triple co-flow burner. The use of He curtain flow produced a microgravity level of $10^{-2}-10^{-3}g$ in He-diluted non-premixed counter triple co-flow flame experiments. Flame stability map was presented based on flame extinction and oscillation near extinction limit. The stability map via critical diluent mole fraction with global strain rate was represented by varying outer and inner He-diluted mole fractions. The flame extinction modes could be classified into five: an extinction through the shrinkage of the outmost edge flame forward the flame center with and without self-excitation, respectively ((I) and (II)), an extinction via the rapid expansion of a flame hole while the outmost edge flame is stationary (III), both the outermost and the center edge flames oscillate, and then a donut shaped flame is formed or the flame is entirely extinguished (IV), a shrinkage of the outermost edge flame without self-excitation followed by shrinking or sustain the inner flame (V).

• Magazine of the Korean Society of Agricultural Engineers
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• v.37 no.5
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• pp.101-110
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• 1995

The use of geotextile as reinforced materials in Soil structures has become widespread throughout the world. Geotextile reinforcement has been used in retaining walls, slope of embankment and especially soft foundation, etc. In the past, however, its design and construction have been performed empirically. In this study, to investigate of the effect of geotextiles reinforced slope of the embankment on a very soft foundation, a limit equilibrium analysis program calculating the safety factor of embankment on very soft foundation was developed. The study was focussed on such factors as type of geotextile, tensile strength, amount of reinforcement, and inclination of embankment. And the 4imit equilibrium analysis program was written on the basis of Low's slope stability theory with some modification. The following conclusions were drawn from this study. (1) The orientation of reinforcement can be assumed either horizontal or tangential to the slip circle. The factor of safety with tangential reinforcement is larger than that with the horizontal reinforcement. (2) In general, the factor of safety increases, as the slope reduces. However, it is preferable to use geotextiles with higher tensile strength rather than to reduce the slope of the embankment, because it is difficult to adjust the slope as desired. (3) The factor of safety obtained by numerical computation is affected only by the tensile strength, but not by the type of the geotextile.

• Journal of the Korean Institute of Navigation
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• v.24 no.5
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• pp.373-383
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• 2000

The ship’s safe mooring stability is a principles for the safe cargo handling works at the mooring berth. Today numerous standards, guidelines and recommendations concerning mooring practices, fittings and equipments exist throughout the worldwide maritime industries. In recently, the mooring facilities were constructed as dolphin types at the open sea area apart far from shoreside instead of enclosed coastline area in accordance with increasing ship’s size and for preventing environmental pollution. Therefore the exciting wave condition must be considered as a basic environmental criteria with the wind force and current force for all of the mooring ships at the sea berth facilities. In this study, this added wave force as one of the environmental external forces by using the theoretical formula was applied to the LNG ship in Pyeongtaeg harbor needed the special mooring stability of the sea berth. Through this research, it can be confirmed that wave force is the very important factor in the mooring force and the strength of wave force works much more in the full laden condition than in the lightship condition. And also the wave force changes to non-linear states according to the wave frequency and wave length. In addition, the maximum limit criteria of environmental force of prohibiting the entering ship on the berth and loading works controlled by the port authority concerned of Pyeongtaeg port fully satisfies the condition of the mooring limit force recommended by OCIMF that the safe permitted force of the mooring line have to be within 55 % of MBL.

• Journal of The Korean Society of Integrative Medicine
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• v.6 no.2
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• pp.45-57
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• 2018

Purpose : This study was conducted to evaluate the effects of an task oriented training program combined with action-observation on balance and gait ability of patients with chronic stroke. Method : The subjects of this study were 30 patients with hemiplegia who agreed to participate and were picked up. Participants were randomly divided into equal groups; namely, an experimental group that underwent task oriented training combined with action-observation for at least 30 minutes/day for 6 weeks and a control group that underwent general task-oriented training. Patients' balance was assessed using the Sway Length, Sway Area and Limit of Stability test. In addition, gait ability was assessed using the 10 Meter Walking Test to measure the taken to walk 10 meters. Gait time and speed taken to walk 10 meters were used to examine gait ability. Results : There were significant improvements in the subscales of the balance and gait ability test of those who participated in the action-observational training program, while the control group showed only significant changes in the evaluation items of the sway length in eyes opened condition and gait time. Conclusion : Therefore, Action-observational training program effectively improved the balance and gait ability in patients with stroke.

• Economic and Environmental Geology
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• v.34 no.6
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• pp.601-615
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• 2001

The study area. Boeun-eup Boeun-kun, belongs to Ogchon metamorphic belt which is highly metamorphosed and consisted of complex geologic formations. Even though the geological structures and formations are complex and metamorphosed, the geological investigation and consideration are not enough and consequently the plane failure is occurred in the rock slope which was under construction on 1 : 0.5 gradient. This area is assessed as unstable and additional failure is possible by the discontinuity with same direction of failure surface. Therefore, the authors evaluate the slope stability using various analysis methods such as SMR, stereographic projection method, and the limit equilibrium analysis. In order to analyze stress redistribution and nonlinear displacement behavior caused by stress release, the authors conduct numerical analysis with UDEC and then the behavior of rock mass is analyzed after reinforcements are applied.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.15 no.1
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• pp.64-71
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• 2009

Purpose: to purpose prevent to dysfunction and decrease to pain level use to active therapeutic movement and sling manual, stability exercise in shortening hamstring chronic back patient. Methods: The patient's complain was Buttock and Lower Back Pain due to dysfunction posture work. The subject's initial Pain Scale was 60 of 100(VAS). The Subject Treatment to Sling Mobility exercise, Home exercise, ATM, Sling Stability exercise, sensory motor training During 8weeks for 18 times. Results: The result was Visual Analog Scale(VAS)was decreased 10 of 100 after treatment. Conclusion: Visual Analog Scale(VAS)was decreased 10 of 100 after treatment. Functional Leg Length Was recover to same level. Trunk Flexibility was increase to 18cm. Active Knee Extension ankle was decrease to $15^{\circ}$ limit range of motion due to Lt. Hamstring Shortening limit range of motion $30^{\circ}$. GPS(Gobal Postural System)test was recover to same level. This case study need to sufficient data and times.

• Bulletin of the Korean Chemical Society
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• v.25 no.6
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• pp.833-837
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• 2004

DeniLite$^{TM}$ laccase immobilized platinum electrode was used for amperometric detection of hydroquinone (HQ) and homogentisic acid (HGA) by means of substrate recycling. In case of HQ, the obtained sensitivity is 280 nA/ ${\mu}$M with linear range of 0.2-35 ${\mu}$M ($r^2$ = 0.998) and detection limit (S/N = 3) of 50 nM. This high sensitivity can be attributed to chemical amplification due to the cycling of the substrate caused by enzymatic oxidation and following electrochemical regeneration. In case of HGA, the obtained sensitivity is 53 nA/ ${\mu}$M with linear range of 1-50 $[\mu}M\;(r^2$ = 0.999) and detection limit of 0.3 ${\mu}$M. The response times ($t_{90%}$) are about 2 seconds for the two substrates and the long-term stability is 60 days for HQ and around 40-50 days for HGA with retaining 80% of initial activities. The very fast response and the durable long-term stability are the principal advantages of this sensor. pH studies show that optimal pH of the sensor for HQ is 6.0 and that for HGA is 4.5-5.0. This shift of optimal pH towards acidic range for HGA can be attributed to the balance between enzyme activity and accessibility of the substrate to the active site of the enzyme.

• Journal of Korean Medicine Rehabilitation
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• v.28 no.2
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• pp.105-111
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• 2018

Objectives The purpose of this study was to examine the effects muscle fatigue at the knee muscles on balance during standing in healthy adults. Methods Thirty healthy adults were recruited along with their written informed consent. Subjects were randomly assigned to knee extensor group (fatigue on knee extensor, KE), and knee flexor group (fatigue on knee flexor, KF). And subjects performed exercise with each muscle group until muscle fatigue was induced. They were assessed balance ability by functional reaching test (FRT), limit of stability (LOS), and postural sway (one leg standing, normal eye open (NO), normal eye close (NC), pillow with eye open (FO), and pillow with eye close (FC)) before and after fatigue. Results There were significant group differences balance performances in FRT, anterior of limit of stability, one leg standing, and the muscle fatigue of knee muscles were decreased balance performances. The balance performance was affected by visual sense and proprioception. Conclusions These results show that the muscle fatigue of knee muscles decreased balance performance. Therefore, balance exercise program should be trained without muscle fatigue.

• Tunnel and Underground Space
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• v.12 no.2
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• pp.83-91
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• 2002

Stability analysis of rocky embankment slopes is done by both the limit equilibrium method and the finite difference method. The height or the rocky embankment is approximately 40 m and the side slope is 1 vertical to 1.5 horizontal. The cohesion and internal friction angle of rock debris are assumed zero and 43$^{\circ}$, respectively. For finite difference analysis, strength reduction method is used to calculate the saft factor of the slope. As a result, the safety factor of the slope is discovered to be 1.4 by using either methods. Considering that the design criteria of the safety factor is 1.3, it can be judged that the rock fragments embankment slope is in a stable state.

• PNF and Movement
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• v.17 no.1
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• pp.19-29
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• 2019

Purpose: This study was an investigation of the effects of the bridge exercise with the sensory feedback of combined abdominal drawing-in on transverse abdominal and balance in patients with stroke. Methods: Forty subjects were randomly assigned into two groups. Subjects in the bridge exercise group (BG, n = 20) or feedback drawing-in bridge exercise group (FDBG, n = 20) were studied for 30 minutes each, twice daily, for four weeks. Outcomes were measured using affected weight distribution (AWD), anterior limit of stability (ALOS), posterior limit of stability (PLOS), timed up-and-go test (TUG), the Berg balance scale (BBS), and transverse abdominis thickness (TRA) before and after the four-week intervention period. Results: There were significant effects in the FDBG pre-intervention and post-intervention in AWD, ALOS, PLOS, TUG, BBS, and TRA. Conclusion: The results of this study suggest that the bridge exercise with sensory feedback combined with abdominal drawing-in could be beneficial for patients with stroke in terms of transverse abdominal and balance.