• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.23 no.2
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• pp.185-191
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• 2013

This paper presents a new method for roller design of IRB(isolation roller bearing) seismic isolation device using experimental evaluation. Three layered plate is adopted for the IRB in which the upper plate is placed on x direction and the lower plate is placed on y direction. The rollers placed in each plate make a plate movement. The roller is then optimally designed using variable geometric conditions. Stress distribution depends on the diameter and length of the roller and hence this is used for the determination of optimal geometry of the roller. In the experimental evaluation, it is observed that stress concentration at the end sides of roller is decreased and geometric coefficients depend on crowning dimension. In addition, in order to determine optimal design parameters of the roller the plastic deformation and friction are experimentally identified.

• Korean Institute of Interior Design Journal
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• v.23 no.6
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• pp.14-21
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• 2014

Kengo Kuma is one of the features of the building is 'natural architecture'. He is saying that the construction of the building in which he is seeking is a natural material of construction is only applied to the issue as to whether the material nature, but that the relationship between humans, the environment, natural point of view in his book. Like repeating units are part of the two hundred ninety-four came mainly small ways to create a relationship, or have architectural features make up the sum of his architecture. I present a comprehensive study is reported in terms of that the 'grain' of such a small part of the unit, according to the architecture of Kengo Kuma mainly granulation characteristics of the construction of one of the practical expression studies Kengo Kuma. Is represented as louvers, check pattern, hole, granulation unit such trend, but have become developed in other directions such simple types are combined. Analysis and particle characteristics in terms of the architectural space of Kengo Kuma, serve as the purpose of the present study reveal that each of the features that have a meaning in the construction of any Kengo Kuma.

• Journal of Oriental Neuropsychiatry
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• v.23 no.3
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• pp.161-174
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• 2012

Objectives : The purpose of this study is to study as reference for practical application in clinics, examine the procedure of historical changes and compare components and their doses of herb medicines, which are recorded in the chapter, Sinmun Jeonkwang of "Donguibogam". Methods : I examined 19 Herb Medicines (Ed note: no need to capitalize the 'h' and 'm') in Chapter Sinmun Jeonkwang of "Donguibogam". Fourteen books, which were noted in Chapter Sinmun Jeonkwang of "Donguibogam" and 16 books in Jeonkwang part of "The Eastern Medical Textbook of neuropsychiatry" and 25 books were mentioned in same part of "Uibujeonrok", were selected as reference. Results and Conclusions : Fourteen documents were referred to the 19 Herb Medicines in Chapter Sinmun Jeonkwang of "Donguibogam". Seventeen Herb Medicines were recorded in the source book but 2 Herb Medicines were not recorded. Fourteen Herb Medicines among 19 were recorded in the source book, which were directly quoted from the firstly appeared books, and 3 Herb Medicines were re-quoted from the other books that succeeded the source books. I suspect that the components and dosages of the Herb Medicines were revised, according to the author's clinical experience and circumstances.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.2_2
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• pp.233-244
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• 2020

A double-parked car is the one that is parked in a crowded parking lot with its transmission gear in neutral position and its auxiliary brake released. A double-parked car can be moved by pushing it but doing so is very difficult and dangerous. In a previous study, we proposed an omni-directional mobile robot for moving a double parked car. In that study we adopted Mecanum wheels. Even though the proposed robot showed successful results, it has some drawbacks such as dependency on a load condition, complexity in control, inefficiency in power use, etc. To overcome those drawbacks, we propose a differential drive robot with ordinary two tire wheels. The proposed robot consists of two parts, one is a wheel part and the other is a body part. By selectively connecting or disconnecting those two parts with the aid of an electric brake, the proposed robot is able to have omni-directional mobility.

• Physical Therapy Korea
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• v.23 no.4
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• pp.47-54
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• 2016

Background: Losing balance during locomotive actions becomes an increasing threat to both the community-dwelling elderly and elderly with Parkinson disease (PD). Those with PD may be at a high risk of fall due to particular characteristics during the turn. Turning around during locomotive actions may be one of problematic factors causing losing balance. Objects: This study is part of a larger study, which in part aims to identify turning strategies, to compare the strategies in the elderly with and without idiopathic PD aged 51 years and older and to distinguish whether the turning strategies can predict the elderly at risk of falls. Methods: A total of 22 community-dwelling elderlies (10 elderlies with idiopathic PD and 12 healthy elderlies) were investigated for the turning strategies during the timed up and go test. Results: There were some significant differences between the two groups during turning (p<.05). The idiopathic PD group had a tendency of challenging on taking more number of steps, more time to accomplish and staggering more for the turn relative to the control group. Conclusion: Taking more number of steps and more time to turn may be useful for distinguishing the characteristics of PD from that of the healthy elderly in turning strategy.

• International Journal of Internet, Broadcasting and Communication
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• v.8 no.2
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• pp.23-30
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• 2016

In this paper, for the pratical building envoronments, the propagation properties of the electromagnetic waves of the sub-1GHz bands, including the 447MHz, 868MHz, and 715MHz, and the 2.4GHz band are experimentally observed in therms of the received signal strength indicator (RSSI) value. The compasion of the frequency bands can be utilized to efficiently construct the wireless sensor networks (WSN) for the building automation control. In order to measure the RSSI values in the building, an RSSI measurement system is first designed, in which the master part can transmit data packets and measure the corresponding RSSI values, and the slave part can respond the received data packets. Using the measurement system, the RSSI values are then experimentally measured at four types of building enviroments. From the experimental result analysis, we could notice that the sub-1GHz, especially the 447MHz band, showd a good communication performance for the building environment and could provide an efficient WSN construction when the data rate is relatively low.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.23 no.7 s.166
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• pp.1164-1172
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• 1999

In this study, to investigate the fatigue crack retardation behavior and the variability of retardation cycles, fatigue crack growth tests were conducted on 7075-T6 aluminum alloy under single tensile overload. A retardation coefficient, D was introduced to describe fatigue crack retardation behavior and a random variable, Z to describe the variability of fatigue crack growth. The retardation coefficient was separately formulated according to retardation behavior which is composed of delayed retardation part and retardation part. The random variable, Z was evaluated from experimental data which was obtained from fatigue crack growth tests under constant amplitude load. Using these variables, a probabilistic model was developed on the basis of the modified Forman's equation, and retardation behavior and cycles were predicted under certain overload condition. The predicted retardation curve well agrees with the trend of experimental crack retardation behavior. And this model well predicts the scatter of experimental retardation cycles.

• Archives of Reconstructive Microsurgery
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• v.23 no.2
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• pp.65-69
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• 2014

Purpose: Soft tissue reconstruction is essential for recovery of finger function and aesthetics in any traumatic defect. The authors applied a reverse homodigital artery island flap for soft tissue defect on distal part of digits. The aim of this study is to evaluate the efficacy of the procedure. Materials and Methods: Seven cases of soft tissue defects of finger tip were included in this study. There were six male and one female, mean age was 43 years and mean follow-up period was 38 months. The length of flaps ranged from 2.0 to 2.5 cm and width ranged from 1.0 to 2.0 cm. Flap survival, postoperative complications were evaluated. Results: All flaps survived without loss. Donor sites were repaired with primary closure in five cases and skin graft in two cases. None of the patients showed significant complications and their average finger motion was $255^{\circ}$ in total active motion at the last follow-up. Conclusion: The authors suggest that the reverse homodigital artery island flap could be a versatile treatment option for the soft tissue defect on distal part of digits.

• Journal of Sensor Science and Technology
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• v.23 no.1
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• pp.46-50
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• 2014

In this paper, we report a novel algorithm based on phase displacement, which supplements conventional TOF methods for distance measurement using an ultrasonic wave. The proposed algorithm roughly measures the distance between the transmission part and the receiving part by using the initial TOF. Thereafter, the precise distance is determined by measuring the phase displacement value between the synchronizing transmission signal and the signal obtained at the receiving end. A distance measurement experiment using a micrometer was performed to verify the accuracy of the ultrasonic wave sensor system. We found that the mean errors from the one adopting the distance measurement algorithm based on phase displacement varied from a minimum of 0.03 mm to a maximum of 0.09 mm. In addition, the standard deviation varied from a minimum of 0.04 mm to a maximum of 0.07 mm, thus giving a precision of ${\pm}0.1$ mm.

• Journal of Agricultural Extension & Community Development
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• v.23 no.4
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• pp.387-403
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• 2016

This paper estimated the demand function of the cuts of Korean beef and imported beef by using the consumer panel and retail price data from the Korean Agro-Fisheries & Food Trade Corporation, and the weather data from the Korea Meteorological Administration with an log-log model and AIDS model. The results show that the preference for cuts of beef used for cooked soup, steamed dish, Changjorim are more elastic than cuts used for roasting when there is a change in price and income in the estimation of demand function of Korean beef. On the other hand, consumers respond sensitively with the demand of roasting part compared to steamed dish, Changjorim, soup when there is change in price and income in the estimation of demand function of imported beef. The results indicate that there is substitutional relationship between Korean beef and imported beef, because Korean beef cuts used for roasting can substitute for imported roasting part and the same relationship applies to steamed dish, soup, Changjorim. In addition, family number, family member, husband job, purchasing place, means of transportation, purchasing time, weather are statistically significant.