• Transactions on Electrical and Electronic Materials
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• v.2 no.2
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• pp.42-45
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• 2001

An ozone condensation system is evaluated from the viewpoint of an ozone supplier for Bi-superconductor thin film growth. An ozone condenser by a selective adsorption on the silica gel surface is constructed. Ozone density is evaluated by three methods; ultraviolet absorption, thermal decomposition and Q-mass analyzing methods. Thermal decomposition method is found to be available to the density evaluation from dilute to highly condensed ozone. The highest ozone density condensed by the adsorption method is evaluated to be 97 mol%.

• Journal of Biosystems Engineering
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• v.23 no.2
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• pp.179-186
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• 1998

This study was conducted to sense posture of an autonomous tractor using a DGPS, a gyro compass, and a potentiometer. Posture sensing system was constructed and its accuracy was evaluated. The accuracy of DGPS was evaluated under stationary and moving conditions, and the performance of the gyro compass and the potentiometer was investigated by measuring bearing and steering angles, respectively. Also, the effect of DGPS interference by obstacles was evaluated experimentally. The position accuracy was about 6.6cm(95%) under the stationary condition and 10 cm at sharp turning condition. Steering angle of the tractor could be related linearly to the output of the potentiometer that was installed on the rotating center of a knuckle arm. The positioning accuracy of the DGPS varied significantly according to the number of visible GPS satellites, but was good with more than 7 satellites. The DGPS gave bad solutions for sensing the posture of tractor when signals from satellites or the correction data from the base were interfered by obstacles.

• Journal of radiological science and technology
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• v.42 no.6
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• pp.455-460
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• 2019

This study compared the radiation transmission and image quality of polymethylmethacrylate (PMMA), polycarbonate (PC), and carbon, which are common components of the compression plates currently used during breast imaging. In addition to measuring the transmitted dose and the intensity without the use of a compression paddle, the four different compression paddles were evaluated according to the material and thickness of each paddle. Radiation transmittance, maximum intensity, and plot profile type w ere all evaluated for each material, and for each factor evaluated the follow ing order w as noted, from best to w orst: carbon 4 mm, PMMA 3 mm, PMMA 4 mm, and PC 4 mm. It is necessary to study a variety of materials and thicknesses in order to find the optimal combination of material and thickness, because not only does the material have a large influence in reducing the radiation exposure during mammography, but the thickness of the compression plate also has a great influence.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.10a
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• pp.193-199
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• 2000

Control system for cutting piston used in vehicle that is one of the 3D shape cutting using CNC lathe is presented. In order to cut the hybrid piston shape using CNC lathe, defined piston shape and change into machine code. The control software was developed for the high speed piston shape cutting. In this paper, the performance of this software was evaluated practically. As a result, the evaluated cutting precision was quantitatively compared with theoretical precision. Also the productivity and the quality by using CNC lathe with control software were evaluated those by using profiling.

• Proceedings of the KWS Conference
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• 2009.11a
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• pp.83-83
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• 2009

The automotive chassis components are structural assemblies that support the engine, suspension, and steering components of the vehicle. For the development of AHSS components, the durability analysis is important. In this paper, the low cycle fatigue property of AHSS was evaluated for the geometry complex and local plasticity in the base material. The GMAW optimization was implemented for the weld soundness using the moving least square method. And the weld S-N curves of AHSS were evaluated to access durability analysis for the weld region. For the verification, the durability analysis of the couple torsion beam axle (CTBA) was performed and compared to the rig test result. The durability analysis using the low cycle fatigue property and the evaluated weld S-N curve of AHSS met the good agreement with the test result.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.30 no.3
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• pp.220-226
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• 1994

In this paper the failure mechanisms of polypropylene resin composites filled with calcium carbonate particulates have been studied in the temperature range $-50^{\circ}C$ to $-50^{\circ}C$ The fillers used are both untreated and surface treated with stearic acid. The impact fracture toughness is evaluated from the impact energy absorbed divided by the uncut ligament area of the specimen. Impact fracture toughness increases as temperature is raised whether the fillers are coated or not. The static fracture toughness of these particular composites is evaluated based on the linear clastic fracture toughness of these particular composites is evaluated based on the linear clastic fracture mechanics. Static fracture toughess decreases with increasing temperature whether the fillers are coated or not. An extended stress whitened zone are observed through a large number of availabel sites for cavitation/debonding along particle matrix interface and matrix deformation.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.12
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• pp.1315-1321
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• 2009

In the present work, vibration control performance of active camera mount system for unmanned aero vehicle(UAV) is evaluated. An active mount featuring inertia type of piezostack actuator is designed and manufactured. Then, vibration control performances are experimentally evaluated. A camera mount system with four active mounts is constructed and mechanical model is established. The governing equation for the camera mount system is obtained and control model is constructed in state space model. Sliding mode controller which has inherent robustness to external disturbance is designed and implemented to the system. Vibration control performances are evaluated at each mount and center of gravity point. Effective vibration performances are obtained and presented in time and frequency domains.

• Nuclear Engineering and Technology
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• v.34 no.6
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• pp.533-544
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• 2002

The neutron induced nuclear data for Mo-95, Tc-99, Ru-101 and Rh-103 was calculated and evaluated in the fast energy region. The energy dependent optical model potential parameters were extracted based on the recent experimental data and applied up to 20 MeV. The s-wave strength function was calculated from the parameters. Spherical optical model, statistical model in equilibrium energy, multistep direct and multistep compound model in pre-equilibrium energy and direct capture model were used in the calculation. The theoretically calculated cross sections were compared with the experimental data and the evaluated files The model- calculated total and capture cross sections were in good agreement with the reference experimental data. The direct capture contribution improved the capture cross sections in pre- equilibrium region. The evaluated cross section results were compiled to ENDF-6 format and will improve the ENDF/B-Vl.

• Nuclear Engineering and Technology
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• v.35 no.1
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• pp.35-44
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• 2003

The neutron induced nuclear data for Eu-153, Gd-155 and Cd-157 are calculated and evaluated in the high energy region. The evaluation procedure for deformed nuclei is setup by using Ecis-Empire codes. The energy dependent optical model potential parameters are searched based on the recent experimental data and applied up to 20 MeV. Optical model, full featured Hauser-Feshbach model and multistep direct and multistep compound model are used in the calculation. The direct-semidirect capture model and the direct coupled-channels contribution to discrete levels are introduced to improve the capture and inelastic scattering cross sections. The theoretically calculated cross sections are compared with the experimental data and the evaluated files. The model-calculated total and capture cross sections are in good agreement with the reference experimental data. The evaluated cross section results are compiled to ENDF-6 format and are expected to improve the ENDF/B-Vl.

• Journal of Fisheries and Marine Sciences Education
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• v.22 no.4
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• pp.553-565
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• 2010

The paper aims to evaluate the quality of fisheries census statistic and to provide some desirable directions and improvements for the future fisheries census, conducted by the Government. For the quality diagnosis of fisheries census statistic, specific processes of fisheries census and statistical qualities of each dimension are surveyed and evaluated by a Government's practician, two external examiners and a research group. Results show that census design, data analysis and quality control are evaluated relatively low in specific processes, and accessibility and comparability are evaluated relatively lower than relevance, accuracy, timeliness and consistency in statistical qualities. For minimizing the sampling errors, the probability proportion method should be employed in sampling methods from currently simple sampling method. In addition, fisheries census statistic is desirable to include and compare with those of different countries for consumer oriented data system.