• Journal of the Korea Institute of Military Science and Technology
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• v.15 no.3
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• pp.250-256
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• 2012

Unmanned ground vehicles may be operated by remote control unit through the wireless communication or autonomously. However, the autonomous technology is still challenging and not perfectly developed. For some reason or other, the wireless communication is not always available. If wireless communication is abruptly disconnected, the UGV will be nothing but a lump of junk. What was worse, the UGV can be captured by enemy. This paper suggests a method, autonomous return technology with which the UGV can autonomously go back to a safer position along the reverse path. The suggested autonomous return technology for UGV is based on multi-correlated information based DB creation and matching. While SUGV moves by remote-control, the multi-correlated information based DB is created with the multi-sensor information; the absolute position of the trajectory is stored in DB if GPS is available and the hybrid MAP based on the fusion of VISION and LADAR is stored with the corresponding relative position if GPS is unavailable. In multi-correlated information based autonomous return, SUGV returns autonomously based on DB; SUGV returns along the trajectory based on GPS-based absolute position if GPS is available. Otherwise, the current position of SUGV is first estimated by the relative position using multi-sensor fusion followed by the matching between the query and DB. Then, the return path is created in MAP and SUGV returns automatically based on the MAP. Experimental results on the pre-built trajectory show the possibility of the successful autonomous return.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.2
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• pp.219-227
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• 2022

In Korea, as the aging phenomenon accelerates, the problem of traffic accidents related to the elderly is continuously emerging. Efforts to improve this are being implemented, but unfortunately the results of these effects are not clear. Therefore, in this study, the effect of traffic characteristics and incentive policies on the return of driver's licenses of elderly drivers was reviewed. As a result of the analysis, it was confirmed that the intention to return the driver's license was low in the case of men, older people, those with low dependence on public transportation, those who undertook long driving hours, and those who took frequent trips. On the other hand, financial incentives were found to play a positive role with regard to the intention to return the driver's license. However, the effect is expected to be insignificant for those with a low intention to return the driver's license. As a result, under the current policy, it is predicted that there is a limit to improving the social problems caused by elderly drivers, meaning that it is necessary to review approaches that induce the return of their driver's licenses.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.15 no.1
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• pp.81-97
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• 2004

The purpose of this study is to suggest management information through the analysis of relationships between financial characteristics and financial performance to the owners and managers of super deluxe hotels in Korea. The data of super deluxe hotels were collected by the electronic F/S announcement system. Forty-two hotels, which have financial statements for the previous three consecutive years were chosen as the sample of analysis. Return on total assets and times interest earned, asset turnover, current ratio of the super deluxe hotels are correlated. Return on total assets and asset turnover, sales growth rate, times interest earned are also correlated. And productivity and asset turnover of chain hotels are correlated. Based on this study, it can be concluded that chain hotels are maily correlated with growth ratio and activity ratio. Otherwise non-chain hotels are mainly correlated with current ratio and safety ratio.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.736-737
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• 2007

The single point bonding in underground transmission system can induce high voltage on the sheath when ground fault, lightning serge and switching serge occurs, at that time underground cable systems cannot offer a return path of fault current. Accordingly if fault current, which cannot return to ground, flows at the single point bonding, high voltage can be induced in SVL and that voltage can cause aging and breakdown of SVL. Therefore this paper study on the effect of parallel ground conductor at the single point bonding when ground fault and lightning serge occurs by using ATPDraw.

• Proceedings of the Korea Water Resources Association Conference
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• 1987.07a
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• pp.223-234
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• 1987

A weakly nonlinear solution is presented for the two-dimensional wave kinematics forced by a generic wavemaker of variable-draft. The solution is valid for both piston and hinged wavemakers of variable-draft that may be double articulated. The second-order propagating waves generated by a planar wave board are composed of two components; viz., a Stokes second-order wave and a second-harmonic wave forced by the wavemaker which travels at a different speed. A previously neglected time-independent solution that is required to satisfy a kinematic boundary condition on the wavemaker as well as a mixed boundary condition on the free surface is included for the first time. A component of the time-independent solution is found to accurately estimate the mean return current(correct to second-order) in a closed wave flume. This mean return current is usually estimated from kinematic considerations by a conservation of mass principle.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.548-551
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• 2004

Magnetostrictive actuators have seen increasing use in fine positioning system because it has many advantages such as friction free, resolution of ${\mu}{\textrm}{m}$ or nm scale, and powerful output force. Usually, the magnetic circuit of magnetostrictive actuator has components which are flux return path, coil, and magnetostrictive material. It is classified in two types according to existence of the permanent magnet. The magnetic circuit having optimal performances transfer magnetic field which is obtained by providing input current at coil without energy loss. This paper described mathematical model of magnetic circuit for getting design variables. The modeling equation is obtained from the relations between flux and reluctance of the magnetic equivalent circuit. Also, finite element analysis has been used to study the performance of magnetic circuit according to change of design variables such as existence and shape of the permanent magnet, flux return path etc. The modification of dimensions enables us to optimize magnetic circuit.

• Korean Journal of Organic Agriculture
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• v.28 no.1
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• pp.59-68
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• 2020

This study analyzed and suggested management situations and improving issues on a consumer cooperatives which has supplied environmentally friendly agricultural products from the year 2002. Indices of management analysis are stability ratio, activity ratio and profitability ratio. Management Stability ratio indices are debt ratio, net worth ratio, fixed ratio and current ratio. Management activity ratio ones include fixed assets turnover and net worth turnover. And profitability ratio is showed through return on investment, net return on sales and return on equity. In order to analyze these indices, financial statements after the closing entires are used each year.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1658-1660
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• 1994

This paper describes the measurement system of the magnetic field waveforms generated by lightning return strokes. The frequency bandwidth of magnetic field measurement system is from 270[Hz] to about 2.3 [MHz]. As the application experiment, the magnetic field generated by simple impulse and oscillating impulse currents, which are measured by a current transformer (Tek. AM503), is observed by the trial magnetic field measurement system. The obtained results are agreement with each other. A typical magnetic field waveform associated with lightning return strokes was recorded and presented.

• Korean Journal of Organic Agriculture
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• v.26 no.4
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• pp.599-607
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• 2018

This study analyzed the management situation of two organizations that have produced environmentally friendly agricultural and livestock products. One organization sells and processes environmentally friendly agricultural products like as grains, vegetables, fruits and processing foods. Another organization processes and sells environmentally friendly livestock products, specially beef products. Indices of management analysis are stability ratio, activity ratio and profitability ratio. Stability ratio indices are debt ratio, net worth ratio, fixed ratio and current ratio. Activity ratio ones include fixed assets turnover and net worth turnover. And profitability ratio is showed through return on investment, net return on sales and return on equity.

• Korean Journal of Organic Agriculture
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• v.30 no.4
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• pp.471-483
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• 2022

This study analyzed management situations of two organizations that have produced environment-friendly agricultural and processed meat products. 'A' farming corporation sells environment-friendly agricultural products like as grains, vegetables, fruits and processing foods. 'B' agricultural corporation processes and sells environment-friendly processed meat products, specially organic and antibiotic-free beef products. Recently, members and production areas of 'A' farming corporation have decreased because of their aging and labor shortage. And Indices for the management analysis are stability ratio, activity ratio and profitability ratio. Stability ratio indices are debt ratio, net worth ratio, fixed ratio and current ratio. Activity ratio ones include fixed assets turnover and net worth turnover. And profitability ratio is showed through return on investment, net return on sales and return on equity.