• Journal of Korean Society of Water and Wastewater
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• v.37 no.6
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• pp.347-361
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• 2023

Water utilities are making various efforts to reduce water losses from water networks, and an essential part of them is to recognize the moment when a pipe burst occurs during operation quickly. Several physics-based methods and data-driven analysis are applied using real-time flow and pressure data measured through a SCADA system or smart meters, and methodologies based on machining learning are currently widely studied. Water utilities should apply various approaches together to increase pipe burst detection. The most intuitive and explainable water balance method and its procedure were presented in this study, and the applicability and detection performance were evaluated by applying this approach to water supply pipelines. Based on these results, water utilities can establish a mass balance-based pipe burst detection system, give a guideline for installing new flow meters, and set the detection parameters with expected performance. The performance of the water balance analysis method is affected by the water network operation conditions, the characteristics of the installed flow meter, and event data, so there is a limit to the general use of the results in all sites. Therefore, water utilities should accumulate experience by applying the water balance method in more fields.

• Progress in Superconductivity and Cryogenics
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• v.18 no.3
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• pp.25-29
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• 2016

A quench detection system of KSTAR Poloidal Field (PF) coils is inevitable for stable operation because normal zone generates overheating during quench occurrence. Recently, new voltage quench detection method, combination of Central Difference Averaging (CDA) and Mutual Inductance Compensation (MIK) for compensating mutual inductive voltage more effectively than conventional voltage detection method, has been suggested and studied. For better performance of mutual induction cancellation by adjacent coils of CDA+MIK method for KSTAR coil system, balance coefficients of CDA must be estimated and adjusted preferentially. In this paper, the balance coefficients of CDA for KSTAR PF coils were numerically estimated. The estimated result was adopted and tested by using simulation. The CDA method adopting balance coefficients effectively eliminated mutual inductive voltage, and also it is expected to improve performance of CDA+MIK method for quench detection of KSTAR PF coils.

• IE interfaces
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• v.17 no.spc
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• pp.79-89
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• 2004

Supply Chain (SC) can balance demands with supply activities as executing Supply Chain Planning (SCP). The fluctuated demands, however, will break the balance between demand and supply. It means that the present SCP is useless in responding the changed demands. Thus it is necessary for SCP to be updated with changed demands. We call this procedure as Supply Chain Replanning. However, the existing measures for SC can not deal with the balance between supply and demand so that they can not detect effectively the timing of replanning. For this reason, a new performance measure, Balancing Point, is developed using momentum, a concept of Physics. It can treat the balance between supply and demand. Also, a replanning method based on Balancing Point is proposed. The proposed method is more effective than the existing replanning method, periodic replanning method and net inventory method.

• The Journal of Korean Physical Therapy
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• v.13 no.3
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• pp.701-710
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• 2001

The purpose of study was to compare the effect of balance performance in the Down syndrome child by the Sensorimotor program. Twenty-four aged 8 to 16 years participated in this study. Participants were divided into experimental(12) and control group(12). Experimental group were received sensorimotor program in three times a week for 6 weeks. But control group were not participants this program. All subjects were assessmented to clinical test such as Oseretsky and Berg balance test. Experimental and control subjects were tested before, after and end(after summer vacation)of the trial. The results were as follow; 1. The physique of Down syndrome child is more dropped than normal child. 2. Balance of Down syndrome child prior to test is clearly dropped. but effect of Sensorimotor program is appeared in experimental group. 3. Balance of experimental group is more decreased than prior to during the summer vacation.

• The Journal of Korean Physical Therapy
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• v.12 no.1
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• pp.57-63
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• 2000

The purpose of this study was to evaluate of balance performance and to examine the relationship between balance performance and feet position, platform speed. Twenty two subjects(men 8, women 14, mean age 24.45years) performed nine balance test with eyes closed for 25seconds:3 feet position(feet together, feet 12cm in apart, feet 24cm in apart) and 3 platform speed$(100\%,\;70\%,\;40\%)$. The results were as fellows: 1. There are significant difference between center of balance and feet position(p<0.05). 2. There are no significant difference between center of balance and plaform speed(p<0.05). 3. There are significant difference between sway index and feet position(p<0.05). 4. There are significant difference between away index and plaform speed(p<0.05).

• Korean Journal of Applied Biomechanics
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• v.30 no.1
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• pp.83-91
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• 2020

Objective: The study aimed to develop a functional performance index that evaluates the functional performance of Parkinson's patients, i.e., to integrate biomechanical measurements of walking, balance, muscle strength and tremor, and to use multiple linear regression with stepwise methods to identify the most suitable predictors for the progression of disease. Method: A total of 60 subjects were tested for sub-variables of four factors: walking, balance, isometric strength and hand tremors. Potential independet variables were extracted through correlation analysis of the sub-variables and dependent variables, Hoehn & Yahr scale. And then, a stepwise multiple regression analysis using the potential independent variables was performed to identify predictor of Hoehn & Yahr scale. Results: First, the results of the study showed that physical composition and gait had a relatively more correlated with the progression of the disease, compared to balance and hand tremor. Second, Parkinson's functional performance is characterized by dynamic pattern of walking, such as foot clearance and turning angle (TA) of walking, and a high-explained regression model is completed. Conclusion: The study emphasized the importance of walking variables and body composition in minor pathological features compared to Parkinson's patient's balancing ability and hand tremor. Specifically, it revealed that dynamic walking patterns functionally characterize patients. The results are worth considering when assessing functional performance related to the progression of the disease at the site.

• PNF and Movement
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• v.8 no.1
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• pp.67-77
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• 2010

Purpose : The purpose of this study was to investigate the usefulness of clinical balance tests through the correlation of balance evaluation using by forceplate in elderly. Methods : Thirty nine healthy elderly subjects (14 males, 25 females) participated in the study. The subjects were evaluated with clinical balance tests [(Berg balance scale (BBS), Functional reach test (FRT), Tinetti's performance oriented mobility assessment (POMA), and one leg standing (OLS)]. Static balance evaluation was assessed by using forceplate. Center of pressure (COP) parameters were obtained using it as total path distance, total sway area, X mean frequency and Y mean frequency for 20 seconds in the following conditions: (1) comfortable standing with eyes opened and closed, (2) uncomfortable standing with eyes opened and closed. After static balance evaluation tested, dynamic balance evaluation was assessed. COP parameters were error distance and area during sine curve trace. COP parameters were movement time, error distance, and maintained time in the circle during COP movement task. Results : Clinical balance tests showed statistically significant correlation between static and dynamic balance evaluations. Among the clinical balance tests, the BBS, POMA, and OLS showed significant correlation with to assess the balance ability of elderly in clinical setting both evaluations. Conclusion : Clinical balance tests can be recommended in clinical setting because of low costs and simplicity.

• Journal of Korean Physical Therapy Science
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• v.31 no.1
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• pp.1-15
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• 2024

Background: This study was conducted to apply active release techniques to male youth basketball players to help improve physical development and damage prevention and improve performance through improved balance and functional movement. Design: Randomized control trial. Methods: The subjects included 33 youth basketball players who were randomly assigned to the experimental group (n=17) and the control group (n=16). For the experimental group, the active release technique was applied to the hip muscles, calf muscles, posterior thigh muscles based on the distribution of injuries surveyed in youth basketball players in the Korean Basksetball League. The Y-balance test and the functional reach test (FRT) were used to assess balance and the Functional Movement Screen (FMS) was used to assess functional movement. Interventions were conducted twice a week for 4 weeks at 40 minutes per session. The experimental group was the active release technique group, and static stretching, a common exercise therapy technique, and self-myofascial release using a foam roller were applied for 20 minutes. The control group received general exercise therapy and placebo active release technique. The placebo active release technique applies pressure only. results:The experimental group showed a greater improvement in balance, as evidenced by the FRT, compared to the control group, which received general exercise treatment. However, there was no statistically significant difference in improvement between the 2 groups. In the case of the experimental group, the difference in the Y balance test before and after the intervention was larger than that of the control group, but there was no statistically significant difference. Significant improvement was found in functional movement, as evidence by the FMS, for the trunk stability test (p < 0.05), in-line lunge test (p < 0.05), rotational stability test (p < 0.05), total score (p < 0.05). Conclusion: In this study, the active release technique improved the balance and functional movement of young basketball players more than general exercise therapy. The application of the active release technique is therefore expected to assist in physical development, prevent damage, and improve the performance of youth basketball players.

• Journal of the Korean Society of Physical Medicine
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• v.2 no.1
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• pp.73-84
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• 2007

Purpose : The purpose of this study was to determine risk factors and methods in balance assessment associated with fall in older adults. Methods : This article describes many of the tools that can be used to evaluate the physical parameters associated with fall risk in older adults. Results : Composite ratings of performance(Tinetti balance assessment, Guralnik test battery, Berg balance scale, modified-physical performance test) measures the score compounding the balance measure to determine fall risk. Static balance instruments are composed of FICSIT-4 that measures the ability of maintaining foot positions and CTSIB that measures postural stability. Dynamic balance instrument is composed of functional reach test. To measure walking velocity and mobility, 8-foot up-and-go test and walking around two cones are used. We can use 1-RM and to measure muscular strength, isokinetic dynamometery, and 30-second chair stand to measure lower extremity muscle strength. Conclusion : The described instruments are easy to use and widespread. To select and use these tool kits carefully is considered to be helpful in identifying those who are most likely to fall. The final part of the article includes a brief discussion of the potential role of exercise training interventions to improve these physical parameters and prevent falls.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.3
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• pp.111-117
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• 2008

The aim of this paper was to investigate the fluid dynamic behavior of the automotive closed type water pump with balance hole in order to evaluate and justify its overall hydraulic performance and, in particular to analyze the effects of the balance hole on the reduction of hydraulic flow force of it. The analysis has been peformed by applying the commercial computational fluid dynamics (CFD) code, Fluent, to the solution of the 3-D turbulent flow fields of automotive closed type water pump. The reliability of the employed analysis was demonstrated by the comparison between numerical result and experimental data. Although, hydraulic head of the closed type water pump with 3mm diameter of balance hole decreased by 1.1%, axial flow force was effectively reduced by 13.3%, comparison of it with no hole at design point.