• Journal of the Korean earth science society
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• v.34 no.3
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• pp.209-223
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• 2013

The purpose of this study was to estimate the contributed concentration of each emission source to $CH_4$ by verifying the simulated concentration of $CH_4$ in the Korean peninsula, and then to compare the $CH_4$ emission used to the $CH_4$ simulation with that of a box model. We simulated the Weather Research Forecasting-Community Multiscale Air Quality (WRF-CMAQ) model to estimate the mean concentration of $CH_4$ during the period of April 1 to 22 August 2010 in the Korean peninsula. The $CH_4$ emissions within the model were adopted by the anthropogenic emission inventory of both the EDGAR of the global emissions and the GHG-CAPSS of the green house gases in Korea, and by the global biogenic emission inventory of the MEGAN. These $CH_4$ emission data were validated by comparing the $CH_4$ modeling data with the concentration data measured at two different location, Ulnungdo and Anmyeondo in Korea. The contributed concentration of $CH_4$ estimated from the domestic emission sources in verification of the $CH_4$ modeling at Ulnungdo was represented in about 20%, which originated from $CH_4$ sources such as stock farm products (8%), energy contribution and industrial processes (6%), wastes (5%), and biogenesis and landuse (1%) in the Korean peninsula. In addition, one that transported from China was about 9%, and the background concentration of $CH_4$ was shown in about 70%. Furthermore, the $CH_4$ emission estimated from a box model was similar to that of the WRF-CMAQ model.

• Journal of the Korean Geographical Society
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• v.28 no.4
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• pp.285-297
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• 1993

For the application of the diffusion equation, slope height and maximum slope angle are calculated from the plotted slope profile. Using denudation rate as a solution for the diffusion equation, an apparent age index can be calculated, which is the total amount of denudation through total time. Plots of slope angle versus slope height and apparent age index versus slope height are useful for determining relative or absolute ages and denudation rates. Mathematical simulation plots of slope angle versus slope height can generate equal denudation-rate lines for a given age. Mathematical simulations of slope angle versus age for a given slope height, for equal denudation-rate at a particular profile site, and for comparing to other sites having controlled ages.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.11
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• pp.987-992
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• 2014

Register control of roll-to-roll printing system for printed electronics requires accurate measurement of register errors. The register marks used for the recognition of patterns position between layers have inherently defects due to low printability of register marks themselves, which brings out inaccurate register accuracy and consequently low performance of printed electronics devices. In this study, the compensation methods for the unrecognized or missing register data are proposed to improve the recognition and consequently the control performance of register accuracy in roll-to-roll printing equipment. The compensation methods using the prior data and the linear interpolation are proposed and compared with the case without compensation for the simulation as well as experiment. Only the linear interpolation method could successfully compensate the missing data and consequently improve the register control performance. We should apply the compensation process of the register errors to improve the register control accuracy in the roll-to-roll printing equipment.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.8
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• pp.1268-1274
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• 2009

Various evaluation systems using simulators have been adopted widely for the purpose of training and examination, including marine engineering education area. This paper suggests a PC based evaluation scoring system for simulators where the operation ability of machineries and background knowledges of trainees or examinees are able to be assessed relatively. The scores are based on the 100 point resulted from their responses for a given evaluation scenario under a PID tuning simulation. The mistakes they make during the operation time are integrated firstly to get error sum, and the error sum is transformed secondly to 100 point score according to a formula where the knowledge level of examinee's groups can be compensated and considered reasonably. The implementation result of evaluation system for the given control loop is described and analyzed to show the effectiveness of the suggested configuration as an evaluation tool.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.1
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• pp.61-69
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• 2013

In an evaluation process of aircraft flying qualities, a clear and concise application interface is important since an evaluation process requires numerous repeated evaluation. This flight evaluation program have implemented efficient flight evaluation user interface along with changed trim condition interface and composed of comprehensive evaluation interface have mounted all automated FQ evaluation modules that was selected to be compose of 14 items in respect of an unmanned fixed-wing aircraft. Accordingly when it is necessary to design the flight control system as well as to develop a FQ considered aircraft, this S/W can be utilized as a tool that is a useful test evaluation S/W with scalability and enable to reduce the time and the cost of verification and evaluation process.

• Transactions of the KSME C: Technology and Education
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• v.3 no.4
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• pp.257-264
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• 2015

To maintain sustainability of nuclear energy as an important energy source, both safety problem and Spent Nuclear Fuels(SNFs) problem should be solved. In case of Gen-IV reactors such as fast reactor, SNFs can be used as fuels by using fast neutrons. It can be a suitable treatment method of high-level waste in near future. Liquid metals such as Sodium or Lead-Bismuth Eutectic (LBE) can be possibly used as a coolant to use fast neutrons. In this paper, it was described that natural circulation parameter studies, design analyses, material selections and a completion of facilities. To develop a natural circulation facility, thermal hydraulic analyses were performed. Installation technique of liquid metal natural circulation were secured.

• Transactions of the KSME C: Technology and Education
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• v.3 no.4
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• pp.299-305
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• 2015

Nuclear hydrogen production technology is being developed for the future energy supply system. The sulfur-iodine thermo-chemical hydrogen production process directly splits water by using of the heat generated from very high temperature gas-cooled reactor, a typical Generation IV nuclear system. Nuclear hydrogen key technologies are composed of VHTR simulation technology at elevated temperature, computational tools, TRISO fuel, and sulfur iodine hydrogen production technology. Key technology for nuclear hydrogen production system were developed and demonstrated in a laboratory scale test facility. Technical challenges for the commercial hydrogen production system were discussed.

• Steel and Composite Structures
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• v.21 no.2
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• pp.249-266
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• 2016

The interest of this article lies in the proposition of using bionic method to develop a new sound absorber and analyze the efficient of this absorber in a ski cabin. Inspired by the coupling absorption structure of the skin and feather of a typical silent flying bird - owl, a bionic coupling multi-layer structure model is developed, which is composed of a micro-silt plate, porous fibrous material and a flexible micro-perforated membrane backed with airspace. The finite element simulation method with ACTRAN is applied to calculate the acoustic performance of the multi-layer absorber, the vibration modal of the ski cabin and the sound pressure level (SPL) near the skier's ears before and after pasting the absorber at the flour carpet and seats in the cabin. As expected, the SPL near the ears was significantly reduced after adding sound-absorbing material. Among them, the model 2 and model 5 showed the best sound absorption efficiency and the SPL almost reduced 5 dB. Moreover, it was most effctive for the SPL reduction with full admittance configuration at both the carpet and the seats, and the carpet contribution seems to be predominant.

• Transactions of the KSME C: Technology and Education
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• v.3 no.2
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• pp.131-140
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• 2015

The mono-ski for the paraplegia designed to skiing is formed as seat bucket on the sled. The impact force transferred by snow surface during skiing is absorbed by the leg joints of normal human, but it is transferred to the human body on the seat when using mono-ski. Most of commercially available mono-ski have absorbing device and link mechanism between seat and ski mount in order to complement it. In this study we developed the comfort evaluation model that could provide skiing simulation of mono-ski with hydraulic damper and analyzed vibrational acceleration occurred during skiing uneven surface. The evaluation method used in this study is the international standard BS6841. We evaluated comfort performance of mono-ski in accordance with nozzle adjustment of hydraulic damper.

• Transactions of the KSME C: Technology and Education
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• v.3 no.2
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• pp.155-164
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• 2015

Recently, the robot manipulators are needed more slim size and longer reach and more accurate movement for increasing productivity. So, in this paper, the simulation modeling method and the efficient modeling method for new slim & long reach robot has been investigated for forecasting the slim robot performance before making prototype. To do this investigation, the major parts of robot driving system such as motor, belt and reducer devices and parts assembly method have been investigated mainly. And then, using this developed modeling method the new designed robot will be forecasted about the dynamic performance of new designed robot.