• New & Renewable Energy
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• v.7 no.3
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• pp.29-35
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• 2011

This paper describes an internal flow characteristics of a fuel pressurized blower, used for 1kW domestic fuel cell system. To analyze the flow field inside the diaphragm cavity, compressible unsteady numerical simulation is introduced. SST model with scalable wall function is employed to estimate the eddy viscosity. Moving mesh system is applied to the numerical analysis for describing the volume change of a diaphragm cavity in time. Throughout numerical simulation with the modeling of the inlet and outlet valves in a diaphragm cavity, unsteady nature of an internal flow is successfully analyzed. Force variations on the lower plate of a diaphragm cavity are evaluated in time. It is found that the driving force at the suction stage of a diaphragm cavity is more necessary than that at the discharging stage.

• New & Renewable Energy
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• v.8 no.3
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• pp.6-13
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• 2012

This paper describes unsteady internal flow characteristics of a cathode air blower, used for the 1 kW fuel cell system. The cathode air blower considered in the present study is a diaphragm type blower. To analyze the flow field inside the diaphragm cavity, compressible unsteady numerical simulation is performed. Moving mesh system is applied to the numerical analysis for describing the volume change of the diaphragm cavity in time. Throughout a numerical simulation by modeling the inlet and outlet valves in a diaphragm cavity, unsteady nature of an internal flow is successfully analyzed. Variations of mass flow rate, force and pressure on the lower moving plate of a diaphragm cavity are evaluated in time. The computed mass flow rate at the same pressure and rotating frequency of a motor has a maximum of 5 percent error with the experimental data. It is found that flow pattern at the suction process is more complex compared to that at the discharge process. Unsteady nature of internal flow in the cathode air blower is analyzed in detail.

• Journal of Korean Association for Spatial Structures
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• v.12 no.4
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• pp.81-90
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• 2012

The concrete-filled tube (CFT) column has the excellent structural performance. But it is difficult to connect with column and beam because of closed section. Its Solution, 2 members of ㄷchennel in which Internal diaphragm is installed were welded beforehand and the method of making Rectangular Steel Tube was proposed. According to upside and downside junction shape, Internal diaphragm suggested as symmetric specimen and asymmetric specimen. The upper and lower diaphragm of the Symmetric specimen used the same horizontal and The upper diaphragm of the Asymmetric specimen used the horizontal plate and the lower diaphragm used the vertically plate. In this research, 4 T-shape column to beam steps connections were tested with cyclic loading experiment in order to evaluate the structural capability of the offered connection. Symmetric specimens be a failure in 0.03rad from beam flange. And Asymmetric specimens be a failure in 0.05rad from column interface. The comparison results of All specimens shown similar to energy absorption capacity in 0.02rad.

• Journal of radiological science and technology
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• v.30 no.4
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• pp.335-341
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• 2007

General anatomy classifies diaphragm as muscle of boundary between chest and abdomen, while radiology divides it into right and left hemidiaphragm, because it is more advantageous in radiological diagnosis on chest and abdomen. Based on these anatomic characteristics of diaphragm, this study aimed to measure the height and curvature of right and left diaphragm in simple chest radiography. As a result, this study came to the following conclusions : 1. For all subjects who joined this study, it was found that their mean transverse diameter in internal diameter of thorax(ID) amounted to 293.3 mm(min. 221.0 mm, max 335.3 mm). 2. For the right and left height of diaphragm, it was found that 81.4% showed higher right diaphragm ; 16.2% showed equivalent height between right and left diaphragm ; and only 2.4% showed higher left diaphragm. 3. For higher right diaphragm, it was found that the mean height of right diaphragm amounted to 15.2 mm(min. height = 2.0 mm, max. height = 41.7 mm). 4. For higher left diaphragm, it was found that the mean height of left diaphragm amounted to 11.5 mm(min. height = 4.7 mm, max. height = 30.4 mm). 5. The mean curvature of right diaphragm amounted to 22.9 mm(min. curvature = 10.4 mm, max. curvature = 37.3 mm). 6. The mean curvature of left diaphragm amounted to 22.4 mm(min. curvature = 11.3 mm, max. curvature = 42.2 mm). 7. For possible associations between ID and right/left diaphragm curvature, it was noted that ID was in significantly positive correlations with right diaphragm curvature(r= .427, p<.001) and left diaphragm curvature(r= .425, p<.001) on statistical level. 8. For possible associations between right and left diaphragm curvature, it was found that right diaphragm curvature was in significantly positive correlations with left diaphragm curvature(r= .403, p<.001).

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.87.2-87.2
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• 2011

This paper describes internal flow of a fuel cell's blower, which is mainly used for detached house and apartment. Test blower is operated by a diaphragm, which has suction and discharge port on the top of the blower. For analyzing the internal flow of the blower, three-dimensional Navier-Stokes analysis is introduced in the present study. Hybrid grid system consisted of hexa hedral, tetra hedral and prism mesh is adopted to describe the complex geometry of the diaphragm blower. Throughout the numerical simulation, it is found that the present numerical modeling for analyzing the internal flow of the test blower is suitable for understanding the unsteady nature inside the cavity of the diaphragm. Detailed unsteady flow is analyzed using the results obtained by numerical simulation.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.151-152
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• 2022

When reinforcing an existing building with the Concrete Filled Tube(CFT) structure, it is impossible to form a diaphragm inside with the existing method. Therefore, in this study, a construction method was proposed so that the internal diaphragm could be welded on four sides by using a slot to transmit force.

• Tuberculosis and Respiratory Diseases
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• v.54 no.6
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• pp.645-650
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• 2003

A malignant fibrous histiocytoma (MFH) is a major subset of soft tissue sarcomas, which occurs principally on the extremities or in the retroperitoneum, as well as on the head and neck of elderly patient. However, it is an extremely rare event when a MFH occurs primarily in the diaphragm of a young people. A 25-year-old woman visited our hospital complaining of right chest pain. The chest X-ray showed a diaphragmatic mass. An exploratory thoracotomic biopsy revealed a primary MFH of the diaphragm. The patient was treated with combined chemotherapy consisting of ifosfamide and doxorubicin. A partial response was seen after 6 cycles of chemotherapy. However, she died of brain metastasis 12 months after the diagnosis.

• Journal of Korean Society of Steel Construction
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• v.20 no.6
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• pp.711-722
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• 2008

Existing tube for concrete filled tubular structure is made through welding of four plates irrespective of tube thickness, so production performance is poor and special welding technique is needed to weld the internal diaphragm and through the diaphragm. Therefore, through manufacturing by cold forming development of beam to column connections that is no welding in position of stress concentration is needed. In this study the proposal of beam to column connections details and to making tube specimens by method of bending steel plates, we want to know the compositeeffect between internal anchor and concrete by processing on stress distribution and internal force evaluation of concrete filled tube beam to column connections with a variable of flange welding existence between column and beam, welding quantity between column and diaphragm, existence of concrete in tube, column with diaphragm and general column.

• Journal of the Korean Society for Advanced Composite Structures
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• v.3 no.4
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• pp.27-37
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• 2012

The construction of a moment connection for a rectangular hollow section (RHS) column and a H-shaped beam is difficult because the RHS is a closed section. When a inner diaphragm is used for such a connection, in general, it is installed after cutting the HSS columns, which results in increased construction work. This paper suggests a new fabrication method to overcome such problems: An inner diaphragm is welded to inside a C-shaped section first, and then a column is fabricated by welding two C-shaped sections. This fabrication method is superior to a classic method in terms of constructibility. An experimental and a numerical study using Ansys 9.0 were performed in order to compare the strength of connections with respect to the presence of concrete, the corner shape of diaphragm, and the axis of loading. The experimental results including initial stiffness and ultimate loads are reported and the analytical results including load transfer mechanism, degree of stress concentration, and strain distribution are also reported.

• Steel and Composite Structures
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• v.10 no.3
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• pp.261-279
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• 2010

Generally, a box tube, which is used for an existing square CFT structure, is made by welding four plates. The manufacturing efficiency of this steel tube is poor, and it also needs special welding technology to weld its internal diaphragm and the through diaphragm. Therefore, an interior-anchor-type square steel tube was developed using the method of cold-forming thin plates to prevent welding of the stress concentration position, and to maximize the section efficiency. And, considering of the flow of beam flange load, the efficiency of erection and the weldability of the diaphragm to thin walled steel column, the external diaphragm connection was selected as the suitable type for the welded built-up square CFT column to beam connection. And, an analytical study and tests were conducted to evaluate the structural performance of the suggested connection details and to verify the suggested equations for the connection details. Through this study, the composite effect of the internal anchor to concrete, the resistance and stress distribution of the connections before and after the existing column is welded to the beam, the effective location of welding in connection were analyzed.