• Proceedings of the KSME Conference
• /
• 2001.06e
• /
• pp.207-212
• /
• 2001

Electro-Rheological(ER) fluid are suspensions which show an abrupt increase in rheological properties under electric fields. ER effects arise from electrostatic forces between the starch particles dispersed in the electrically insulating silicone oil, induced when an electric field is applied. Yield stress of the fluids were measured on the couette cell type rheometer as a function of electric fields. This paper presents performance analyses of four types of the two parallel-plate. Which have different electrode length and width but same electrode area. On the basis of the pressure drop and flow rate analysis. Four types of the two parallel-plate are designed and manufactured. Using ER fluid, it is possible to directly interface between electric signals and fluid power without moving parts.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2006.05a
• /
• pp.101-102
• /
• 2006

The purpose of this paper is pulsation-analysis of the swash plate type axial piston pump for excavator and the method of side branch hose application, which is used normally in construction equipments. In this paper, draw the mathematical modeling for pressure pulsation mechanism of the swash plate type axial piston pump for excavator, expression the flow pulsation in the pipelines by transfer matrix method, programmed simulation for pulsation by AMEsim software, and the reliability of that was verified by the comparison with the experimental results.

• Clinics in Shoulder and Elbow
• /
• v.12 no.1
• /
• pp.1-6
• /
• 2009

Purpose: To evaluate and report the clinical and radiological outcomes of open reduction and internal fixation with a mini-T plate for unstable distal clavicle fractures. Materials and Methods: From December 2004 to July 2007, fifteen patients who had a fracture of the distal clavicle (Neer type II fracture) were treated with an open reduction and internal fixation using a mini-T plate. They were followed up for a minimum of one year and the clinical and radiological results were analyzed. Results: The average time to fracture union was 3.1(3~4) months. There were no complications, such as deep infection or fixation loss. The mean ASES score was 97 points (85~100points) at the last follow up period, and 14 patients had a full range of motion of the shoulder. Conclusion: Open reduction and internal fixation with a mini-T plate for unstable distal clavicle fracture is a good surgical method with good clinical and radiological results.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2006.11a
• /
• pp.293-296
• /
• 2006

The results and interpretations of push-out tests on shear connector devices for composite bridges carried out in this study are presented. The devices under investigations are headed studes, perfobond rib, ㄱtype perfobond rib, T- Connector and a new type of shear connector called T type perfobond rib. This new connector is flat steel plate with a number of holes punched through. The results obtained indicate that the T type perfobond rib shear connectors exhibit adequate ductility and substantially higher capacities. Therefore for composite beams utilizing reinforced concrete slabs, the T type perfobond rib shear connectors is a viable alternative to the headed studs.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2009.05a
• /
• pp.55-55
• /
• 2009

• Journal of Korean Neurosurgical Society
• /
• v.41 no.2
• /
• pp.77-81
• /
• 2007

Objective : In a variety of thoracolumbar diseases, corpectomy followed by interbody bone graft and anterior instrumentation has allowed direct neural decompression and reconstruction of the weight-bearing column by short segments fusion. In this study, we compared spinal stability of the two different anterior thoracolumbar instruments : Z-plate and Kaneda device representing plate and two-rods type, respectively. Methods : A retrospective review was performed for all the patients with thoracolumbar diseases or traumas treated with anterior corpectomy, autologous iliac bone graft, and fixation with instruments from 1996 to 2000. For the anterior instrumentation, Z-plate or Kaneda device was used for 24 [M:F=5:9, average age=37] and 12 [M:F=9:3, average age=41] patients, respectively. The plain AP and lateral flexion-extension films were taken immediately after surgery and at each follow-up. The sagittal and coronal Cobb's angles at the operation segments were used to observe the change of initial fixation status. The surgical time length and bleeding amount of the two groups were compared. Intra-operative and post-operative instrument associated complications were evaluated. Student t-test was used for statistical analysis and p-value less than 0.05 was considered to be significant. Results : Mean follow-up durations for Z-plate and Kaneda device were 24 and 21 months, respectively. The fusion rate was 91% for Z-plate and 100% for Kaneda device. Two cases of Z-plate group showed instrumentation failure during the follow up period, in which additional surgery was necessary. The mean differences of sagittal Cobb's angles among the AP images immediate after surgery and at follow-up were 7 and 2 degrees for Z-plate and Kaneda device, respectively [p<0.05]. The mean differences of coronal Cobb's angles were 5 and 2 degrees for Z-plate and Kaneda device, respectively [p<0.05]. No Intra-operative complication has occurred in both groups. There was no difference in surgery time and bleeding amount between two groups. Conclusion : We think that Kaneda device [rod type] is stronger than Z-plate [plate type] to keep the spinal stability after anterior thoracolumbar surgery.

• Proceedings of the KIEE Conference
• /
• 1998.07d
• /
• pp.1534-1536
• /
• 1998

We designed and fabricated plate-type linear ultrasonic motor. It used multi-vibration mode, 1st Longitudinal and 4th Bending mode. To analyze vibration mode and find maximum displacement point, we simulated using FEM(Finite Element Method). The plate-type linear ultrasonic motor was fabricated by the simulation results. Also, to confirm application to card-forwarding device, frequency and load characteristics were measured. Its resonance frequency was 49.6 kHz, and its maximum speed was about 0.6m/s when no load. Also, its maximum efficiency was 1.2 % and in that time, speed and torque was 0.3 m/s and 0.7 mNm, respectively.

• Nuclear Engineering and Technology
• /
• v.53 no.3
• /
• pp.911-919
• /
• 2021

In this paper, the design stress intensity values for the plate-type fuel assembly for research reactor are presented. Through a tensile test, the material properties of the cladding (aluminum alloy 6061) and structural material (aluminum alloy 6061-T6), in this case the yield and ultimate tensile strengths, Young's modulus and the elongation, are measured with the temperatures. The empirical equations of the material properties with respect to the temperature are presented. The cladding undergoes several heat treatments and hardening processes during the fabrication process. Cladding strengths are reduced compared to those of the raw material during annealing. Up to a temperature of 150 ℃, the strengths of the cladding do not significantly decrease due to the dislocations generated from the cold work. However, over 150 ℃, the mechanical strengths begin to decrease, mainly due to recrystallization, dislocation recovery and precipitate growth. Taking into account the uncertainty of the 95% probability and 95% confidence level, the design stress intensities of the cladding and structural materials are established. The presented design stress intensity values become the basis of the stress design criteria for a safety analysis of plate-type fuels.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.22 no.12
• /
• pp.176-182
• /
• 2008

It is the paper that this study develops the small plate-type ozonizer(PTO) for improvements of indoor air and water, and investigated the characteristics. Electric discharge area of ozonizer of each form is same to 60[$cm^2$] and discharge power is the maximum 30[W]. Ozonizer of various forms was devised according to size, numbers and arrangement. The main study object is discharge power-ozone concentration characteristics, discharge power-ozone yield characteristics, amount of gas flow-ozone concentration characteristics and amount of gas flow-ozone yield characteristics. PTOL-P appeared so as to be most excellent, and ozone generation characteristics were able to get the similar results at three kinds of remaining ozonizer ($PTO_{P-P}$, $PTO_{C-P}$, $PTO_{T-P}$).

• Bulletin of the Society of Naval Architects of Korea
• /
• v.12 no.2
• /
• pp.35-42
• /
• 1975

This paper investigates the distribution of stress and its behavior at the Root Toe in fillet welding joint. Furthermore, the stress components and principal stresses in the fillet welds are calculated by the finite element method. The distribution of stresses obtained numerically by means of the finite element method is also compared with the experimental results of two dimensional photoelasticity. A Cover plate type and Center block type of fillet welds are used as models for the numerical calculations covering the variations of 2 W/M(thickness of main plate/thickness of cover plate)=1 through 2W/M=4. The results obtained in these studies are summarized as follows; 1) When W2/M values become small, the stress concentration factors of the Root are larger than of the Toe in a C-type. Its critical value is 2W/M=3.00. However, no critical value exists in a T-type. 2) For 2W/M Values being avove 3.5 in a C-type and above 4.0 in a T-type, $K_R$ and $K_{\tau}$ become 1. 3) According to the differences of 2W/M values, the differences in stress become increasing in the Root but become decreasing in the Toe. These differences, however, disappear as the free boundary surface is approached. 4) The stress concentration factors of both the Root and Toe obtained by means of the finite element method have somewhat lower values than obtained by the photoelasiticity. But their principal stress directions coincide in either method. 5) It proves beneficial to employ the finite element method for two-dimensional plane stress analysis in front fillet welding joint.