• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.9
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• pp.482-495
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• 2017

Degree-days are practically used as a tool to estimate energy consumption for heating and cooling. Degree-days are calculated by summing differences of balance point temperature and outside temperature for the analyzed period. Determining balance point temperature is a key point in calculating accurate degree-days. However, ASHRAE standards are used for balance point temperature in Korea because balance point temperature considering climate conditions and building thermal performance is not proposed in Korea. This study proposes the process to generate balance point temperature for heating degree-days considering Korean climate and building conditions. Also, a new balance point temperature for three regions in Korea will be suggested in this study. Balance point temperature of Seoul is approximately $15.0^{\circ}C$, lower than the current standard of $18.3^{\circ}C$. Balance point temperature of Seoul considering climate conditions and building performance can be different from the ASHRAE suggested value ($18.3^{\circ}C$). Results revealed the current standard for balance point temperature should be changed considering climate and building conditions in Korea.

• Journal of Korean Medicine Rehabilitation
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• v.24 no.3
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• pp.149-155
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• 2014

Objectives This study was designed to investigate the correlation between the difference of pelvic height and difference of gait balance. Methods 62 cases of patients who received treatment from January 2011 to March 2014 for abnormal postures were analyzed. Their difference of pelvic height were estimated by whole spine X-ray analysis and gait balance were estimated by Treadmill Gait Analysis system. The data were analyzed to find out correlation between difference of pelvic height and difference of gait balance, and correlation between the position of pelvic tilt and gait balance higher side. Pearson correlation and Chi-square analysis were used. Results Pelvic height heigher side were more left than right side, and gait balance higher side were also more left than right side. Difference of pelvic height and difference of gait balance had a positive linear relationship, but there was no significant correlation. The position of pelvic tilt had significant correlation with gait balance higher side. Conclusions The position of pelvic tilt had significant correlation with gait balance higher side and difference of pelvic height had no significant correlation with difference of gait balance.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.214-219
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• 2002

As the tangential flow inside the clearance of tribe elements such as bearings and seals is increased as the shaft speed increases, the system stability will be decreased due to the increment of the instability parameter. To reduce the tangential flow inside the clearance of the balance sleeve, anti-swirl injection mechanism is applied. The balance sleeve is used in resisting the axial force induced by impeller in high pressure multi-stage pump. In this paper, total three cases are experimentally investigated; original balance steeve, anti-swirl injection balance steeve with 0 axial degree and anti-swirl injection balance sleeve with 30 axial degree. Experiments are focused in the comparison of vibration level and leakage flow rate. The results clearly shows that the anti-swirl injection balance sleeve with 0 axial degree improves the vibration characteristics. However, the anti-swirl injection balance sleeve with 30 degree aggravates the vibration characteristics. In the standpoint of leakage performance, both anti-swirl injection balance sleeves show the better result than the original balance sleeve.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.8
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• pp.632-638
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• 2002

As the tangential flow inside the clearance of tribo elements such as bearings and seals is increased as the shaft speed increases, the system stability will be decreased due to the increment of the instability parameter. To reduce the tangential flow inside the clearance of the balance sleeve, anti-swirl injection mechanism is applied. The balance sleeve is used in resisting the axial force induced by impeller in high pressure multi-stage pump. In this paper, total three cases are experimentally investigated; original balance sleeve, anti-swirl injection balance sleeve with 0 axial degree and anti-swirl injection balance sleeve with 30 axial degree. Experiments are focused in the comparison of vibration level and leakage flow rate. The results clearly shows that the anti-swirl injection balance sleeve with 0 axial degree improves the vibration characteristics. However, the anti-swirl injection balance sleeve with 30 degree aggravates the vibration characteristics. In the standpoint of leakage performance, both anti-swirl injection balance sleeves show the better result than the original balance sleeve.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1954-1957
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• 2005

A quantitative evaluation of postural balance training using a virtual reality bicycle system was performed. In the experiment, the effectiveness of virtual reality bicycle system on postural balance training was analyzed with four male subjects in their twenties. The parameters measured during cycling were cycling time, average velocity, number of times subject deviated from path, and weight shift. Those parameters were evaluated for the quantification of the extent of control. We also measured the parameters on postural control capability after 5th trial and 10th trial in a balance testing system with a force plate to find out the effectiveness of the training. In the balance test with force plate, it was found out that the weight shift was almost zero and the deviation from the target trace reduced significantly after the training with the virtual cycle. The result showed that the virtual bicycle system was an effective system as a rehabilitation training device.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.7
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• pp.608-615
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• 2012

In this study, we analyzed the system impedance of Unmanned Aerial Vehicle avionics bay and Environmental Control System(ECS), and estimated the proper air flow rate to be supplied avionics equipments. As the result of estimation, we evaluated the performance of ECS after analysing the flow balance rate and the air flow rate about each outlet port, and simultaneously decided the flow balance rate after evaluating the thermal substantiality by the thermal analysis of avionics bay. In order to verify the property of analysis result, we conducted the flow balance test using the actual avionics equipments and finally deduced the flow rate to be met system requirements of avionics equipments. Also, as the analysis results, we verified the satisfaction of system requirements at midium altitude condition and proved the performance characteristics of an Environmental Control System(ECS).

• 전기의세계
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• v.20 no.1
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• pp.19-23
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• 1971

In testing the moving balance of a rotor instead of strobotron system here to for in use, making the pick up touch the rotor without putting the subject on the testing table, we can observe both the corrected original point and its unbalance point which appeared on the Braun tube screen with naked eyes. Then we can do our correcting job with rapidity.

• Journal of the Semiconductor & Display Technology
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• v.12 no.1
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• pp.15-21
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• 2013

In this paper, sensor system and inspection algorithm in order to inspect steel balance weight for automobile is described. Steel balance weight is composed of clip and weight, which is joined by press process. The defective one has a gap between clip and weight. To detect whether there is a gap, sensor system is simply configured with laser line projector and USB camera, which make it possible to measure the height difference of clip and weight area. Laser line pattern which is made on the surface of a balance weight is captured by USB camera. In case that USB camera is used in machine vision, barrel distortion caused by wide angle lens makes the captured image distorted. Image warping function is applied to correct the distortion. Simple image processing algorithm is applied to extract the laser line information and whether it is good or not is judged through the extracted information.

• Journal of The Korean Society of Integrative Medicine
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• v.9 no.4
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• pp.291-298
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• 2021

Purpose: The Pedisole is a newly developed shoe-mounted wearable assessment system for analyzing balance and gait. This study aimed to determine the reliability and validity of the parameters provided by the system for static balance and gait analysis of healthy adults. Methods: This study included 38 healthy adults (22.4±1.9 years) with no history of injury in the lower limbs. All participants were asked to perform balance and gait tasks for undertaking measurements. For analysis of balance, both the smart Pedisole and Pedoscan systems were concurrently used to analyze the path length of the center of pressure (COP) and the weight ratio of the left and right for 10 s. Gait was measured using the smart Pedisole and GaitRite walkway systems simultaneously. The participants walked at a self-selected preferred gait speed. The cadence, stance time, swing time, and step time were used to analyze gait characteristics. Using the paired t-test, the intra-class coefficient correlation (ICC) was calculated for reliability. The Spearman correlation was used to assess the validity of the measurements. In total, data for balance from 36 participants and the gait profiles of 37 participants were evaluated. Results: There were significant differences between the COP path lengths (p<.050) derived from the two systems, and a significant correlation was found for COP path length (r=.382~.523) for static balance. The ICC for COP path length and weight ratio was found to be greater than .687, indicating moderate agreement in balance parameters. The ICC of gait parameters was found to be greater than .697 except for stance time, and there was significant correlation (r=.678~.922) with the GaitRite system. Conclusion: The newly developed smart insole-type Pedisole system and the related application are useful, reliable, and valid tools for balance and gait analysis compared to the gold standard Pedoscan and the GaitRite systems in healthy individuals.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.648-651
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• 2004

Biped robot has better mobility than other mobile robot, but it is hard to maintain balance during walking. In order to maintain balance, stability analysis is a key point for a biped robot. The zero moment point analysis has been used most in stability analysis. In this paper, we propose different method of stability analysis using wrench system. It is possible to generate a wrench system by applying a force along an axis in space and simultaneously applying a moment about the same axis. Wrench system is equivalent to a force and moment applied along the same axis. We compare the result of wrench system analysis with that of zero moment analysis in biped robot stability using simulation program.