• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.36 no.10
• /
• pp.719-723
• /
• 1987

This paper shows the design method and the experimental results of the thin film thickeness monitor. The thin film thickness monitor uses 6 MHz quartz crystal in sensor and cooling system for the fine operation. The thin film thickness are measured by the digital frequrency counter.

• Nuclear Engineering and Technology
• /
• v.54 no.12
• /
• pp.4798-4808
• /
• 2022

The porous corrosion deposits (known as CRUD) adhered to the cladding have an important effect on the heat transfer from fuel rods to coolant in PWRs. The vapor film is the main constituent in the two-phase film boiling model. This paper presents a vapor film thickness correlation, associated with CRUD porosity, CRUD chimney density, CRUD particle size, CRUD thickness and heat flux. The dependences of the vapor film thickness on the various influential factors can be intuitively reflected from this vapor film thickness correlation. The temperature, pressure, and boric acid concentration distributions in CRUD can be well predicted using the two-phase film boiling model coupled with the vapor film thickness correlation. It suggests that the vapor thickness correlation can estimate the vapor film thickness more conveniently than the previously reported vapor thickness calculation methods.

• Explosives and Blasting
• /
• v.10 no.2
• /
• pp.3-7
• /
• 1992

Concerning to Taeku city subway construction project(1-4 site), the original design was adapted NATM Tunnel method to the 8 meter thickness of overburden. Surveyor checked sity and design material and finally decided to change into Open Cut method because overburden is not only below 1 1/2 times thickness of comparate Tunnel width but there is no traffic conjunction in job site.

• Journal of the Korean Society for Precision Engineering
• /
• v.20 no.4
• /
• pp.143-150
• /
• 2003

Frictional properties of ultra-thin carbon coatings on silicon wafer were investigated based on Taguchi experimental design method. Sensitivity analysis was performed with normal load, relative humidity, deposition process, and coating thickness as the variables. It was found that despite low thickness, the carbon coating resulted in relatively low friction coefficient. Also, the frictional behavior was affected significantly by humidity and normal load.

• Korean Journal of Computational Design and Engineering
• /
• v.13 no.4
• /
• pp.296-304
• /
• 2008

Recently, various attempts are being done to apply off-line programming system to field of paint robot. But most commercial simulation softwares have problems that are slow simulation speed and not support various painting paramenters on simulation. This paper proposes enhanced paint simulation method for off-line programming system. For these, this method used the mathematical model of flux field from a previous research. The flux field has the flux distribution function, which reflects on the feature of paint spray. A previous research derived this flux distribution function for an integral function and calculated paint thickness function for an integral function. But if flux distribution function is defined as an integral function, it is inadequate to use for real-time simulation because a number of calculation is needed for estimation of paint thickness distribution. Therefore, we defined the flux distribution function by numerical method for reducing a mount of calculation for estimation of paint thickness. We derived the equation of paint thickness function analytically for reducing a mount of calculation from the paint distribution function defined by numerical method. In order to prove proposed paint simulation method this paper compares the simulated and measured thickness. From this comparison this paper show that paint thickness distribution is predicted precisely by proposed spray paint simulation process.

• 유체기계공업학회:학술대회논문집
• /
• 2004.12a
• /
• pp.419-426
• /
• 2004

A three-dimensional computation was conducted to understand effects of the inlet boundary layer thickness on the loss mechanism in a low-speed axial compressor operating at the design condition(${\phi}=85\%$) and near stall condition(${\phi}=65\%$). At the design condition, the flow phenomena such as the tip leakage flow and hub comer stall are similar independent of the inlet boundary layer thickness. However, when the axial compressor is operating at the near stall condition, the large separation on the suction surface near the casing is induced by the tip leakage flow and the boundary layer on the blade for thin inlet boundary layer but the hub corner stall is enlarged for thick inlet boundary layer. These differences of internal flows induced by change of the boundary layer thickness on the casing and hub enable loss distributions of total pressure to be altered. When the axial compressor has thin inlet boundary layer, the total pressure loss is increased at regions near both casing and tip but decreased in the core flow region. In order to analyze effects of inlet boundary layer thickness on total loss in detail, using Denton's loss models, total loss is scrutinized through three major loss categories in a subsonic axial compressor such as profile loss, tip leakage loss and endwall loss.

• Journal of Computational Design and Engineering
• /
• v.2 no.3
• /
• pp.183-194
• /
• 2015

This paper proposes a novel method for visualizing the thickness and clearance of 3D objects in a polyhedral representation. The proposed method uses the distance field of the objects in the visualization. A parallel algorithm is developed for constructing the distance field of polyhedral objects using the GPU. The distance between a voxel and the surface polygons of the model is computed many times in the distance field construction. Similar sets of polygons are usually selected as close polygons for close voxels. By using this spatial coherence, a parallel algorithm is designed to compute the distances between a cluster of close voxels and the polygons selected by the culling operation so that the fast shared memory mechanism of the GPU can be fully utilized. The thickness/clearance of the objects is visualized by distributing points on the visible surfaces of the objects and painting them with a unique color corresponding to the thickness/clearance values at those points. A modified ray casting method is developed for computing the thickness/clearance using the distance field of the objects. A system based on these algorithms can compute the distance field of complex objects within a few minutes for most cases. After the distance field construction, thickness/clearance visualization at a near interactive rate is achieved.

• Journal of International Academy of Physical Therapy Research
• /
• v.12 no.2
• /
• pp.2365-2369
• /
• 2021

Background: Patients with dysphagia after stroke are treated with neuromuscular electrical stimulation (NMES), but its effect on masseter muscle thickness and bite force in the oral phase is not well known. Objectives: To investigated the effect of NMES on masseter muscle thickness and occlusal force in patients with dysphagia after stroke. Design: Two group, pre-post design. Methods: In this study, 25 patients with dysphagia after stroke were recruited and allocated to either the experimental or the control groups. Patients in the experimental group were treated with NMES to the masseter muscle at the motor level for 30 minutes and were additionally treated with traditional swallowing rehabilitation for 30 minutes. In contrast, patients in the control group were only treated with traditional swallowing rehabilitation for 30 minutes. Masseter muscle thickness was measured using ultrasonography before and after intervention, and bite force was measured using an bite force meter. Results: The experimental group showed significant improvement in masseter muscle thickness and bite force compared to the control group. Conclusion: NMES combined with traditional dysphagia rehabilitation is effective in improving masseter muscle thickness and bite force in patients with dysphagia after stroke.

• Journal of Advanced Marine Engineering and Technology
• /
• v.37 no.8
• /
• pp.843-848
• /
• 2013

As the LNG demands are growing, the constructions of LNG FPSO (Floating Production Storage and Off-loading) and LNG carriers have been constantly increased, and the various design of storage tank has been tried. This paper propose that the material of inner storage tanks is made of 5~9% Ni steel plate and perlite powder insulation instead of urethane foam block. It needs essentially to obtain the proper design specifications that are the pressure of perlite, the characteristics of resilient blanket as the pressure absorber, optimum thickness of blanket and design pressure of tank wall, etc. to enable the perlite insulation system to LNG carrier, The results show that the design thickness of blanket should be between 1/4 to 1/3 of insulation width and the optimum rate becomes 30%, and the design pressure be applied below 1,500 Pa with blanket thickness.

• Journal of Korean Association for Spatial Structures
• /
• v.20 no.2
• /
• pp.87-94
• /
• 2020

The present study is aimed to calculate the optimal damping according to the seismic load on the structure with a non-seismic design to perform structure analysis considering the deformation of structural joint connection and panel zone; to develop design program equipped with structural stability of the steel frame structures reinforced with the panel zone and viscous dampers, using the results of the analysis, in order to systematically integrate the seismic reinforcement of the non-seismic structures and the analysis and design of steel frame structures. The study results are as follows: When considering the deformation of the panel zone, the deformation has been reduced up to thickness of the panel double plate below twice the flange thickness, which indicates the effect of the double plate thickness on the panel zone, but the deformation showed uniform convergence when the ration is more than twice. The SMRPF system that was applied to this study determines the damping force and displacement by considering the panel zone to the joint connection and calculating the shear each floor for the seismic load at the same time. The result indicates that the competence of the damper is predictable that can secure seismic performance for the structures with non-seismic design without changing the cross-section of the members.