• 제어로봇시스템학회논문지
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• 제21권9호
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• pp.869-874
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• 2015

We developed an LSDC (Load Shift and Load Distribution Control) technology in order to improve coil quality and productivity by reducing tension fluctuation especially for the tail of the strip in the down coiler in hot strip mills. To adapt the new controller, the torque and speed distribution between the zero pinch roll, pinch roll, and mandrel are needed. The proposed controller is a combination of an LSC to share the tension between the mill stand and the mandrel, and an LDC to shift the torque load from the zero pinch roll to the pinch roll. From the simulation, the proposed controller is verified under the torque disturbance. Using a field test, the torque deviation decreased by nearly 50% through utilization of the LSDC control.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집A
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• pp.590-595
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• 2000

On the contrary to the increasing needs of shape qualities, most of quality inspections are carried out by manual or operator's insight. To find the causes of shape inferiority, it is required to gather and analyze the shape measurement data. As a result the winding profile measurement system ($TELE-SCANNER^{(R)}$) is developed to analyze the coiling process and automate the manual measuring process for winding profile of hot-rolled coils. The winding profile measurement system measures and analyzes winding profile shapes of hot-rolled coils, and classifies them into several dominant patterns that are related to normal or abnormal mechanical conditions of down-coiler. The system also contains analysis software to quantify the winding profile shapes and patterns, and to produce statistics to help search the causes of profile shape inferiority.

• 대한의용생체공학회:의공학회지
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• 제27권3호
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• pp.94-100
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• 2006

The effectiveness of the treatment of intracranial aneurysms with endovascular coiling depends on coil packing density, the location of aneurysm, its neck dimensions with respect to the aneurysm dome, and its size with respect to the surrounding tissue. Clinical data also suggests that the aneurysm neck size is the main predictor of aneurysm recanalization. In this study, the force impinging on the aneurysm neck in an idealized aneurysm was calculated by using a three dimensional finite volume method for the non-Newtonian incompressible laminar flow. To quantify the effect of neck size on the impingement force, calculations were performed for aneurysm neck diameters (Da) varying from 10% to 100% of the parent artery diameter (Dp). Also, maximum impingement forces were represented by a function of the ratio of the aneurysm neck to the diameter of the parent vessel. The results show that the hemodynamic forces exerted on the coil mass at the aneurysm neck due to the pulsatile blood flow are larger for wide necked aneurysms.

• 제어로봇시스템학회논문지
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• 제17권4호
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• pp.382-387
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• 2011

In this paper, a LBCC (Latter Bank Cooling Control) for the high strength steel is proposed to obtain the desirable temperature and the property of the material along the longitudinal direction of the steel on the ROT (Run-Out Table) process. A cooling valve is modeled to analyze the response of the ROT banks. The control concept is derived from a field data, a valve model considering the valve response and a TTT (Time-Temperature Transformation) diagram. The proposed control is verified from the simulation results under the various carbon quantities. It is shown through the field test of the hot strip mill that the deviation of the CT (Coiling Temperature) is considerably decreased by the proposed temperature control.

• 산업공학
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• 제9권3호
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• pp.298-305
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• 1996

Cold rolling mill process in steel works uses stands of rolls to flatten a strip to a desired thickness. Most of rolling processes use mathematical models to predict rolling force which is very important to decide the resultant thickness of a coil. In general, these mathematical models are not flexible for variant coil types and cannot handle various elements which is practically important to decide accurate rolling force. A corrective neural network is proposed to improve the accuracy of rolling force prediction. Additional variables-composition of the coil, coiling temperature and working roll parameters-are fed to the network. The model uses an MLP with BP to predict a corrective coefficient. The test results using 1,586 process data collected at POSCO in early 1995 show that the proposed model reduced the prediction error by 30% on average.

• 한국패류학회지
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• 제9권2호
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• pp.57-67
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• 1993

A cladistic analysis for phylogenetic relationship among 3 freshwater planorbid snail species was carried out on the basis of their conchological and anatomical characteristics.The intestinal loop in the digestive systims was mainly distinguishable among 3 species of the planorbid snails. The loops in Hippeutis cantori and Segmentina hemisphaerula coiled around stomach, extended down to the distal part of the liver and finally connected with the anus, while the loop in Gyraulus convexiusculus was short and small, and connected directly to the anus after coiling around the stomach. However, the intestinal loop of Hippeutis cantori was the largest among those of 3 target snail species. In the main morpholohical differences of the riproductive systems, Gyraulus convexiusculus uniquely had a calcareous stylet in the penis sheath. Although there was no stylet in the penis sheath in the other snail species, the penis shesths connected with 1 and 2 flagella in Segmentina hemisphaerula and in Hippeutis cantori, respectively were different from each other. Two planorbid species, Hippeutis cantori and Segmintina hemisphaerula have a more recent phylogenetic ancestor out three species employed including Gyraulus convexiusculus.

• Corrosion Science and Technology
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• 제3권5호
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• pp.209-215
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• 2004

Flexible hydraulic hose assembly that consists of hose and joints is used widely on various construction heavy equipments, agricultural machines, motor vehicles, and industrial heavy machines that require flexibility on hydraulic pipelines. It is classified by the maximum usage pressure which is determined by the winding layers of coiling steel wire and the inner diameter of the hoses. In this paper, we designed and performed an accelerated life test for assessing the reliability of a flexible hydraulic hose assembly. In the proposed accelerated life test, typical impulse pressure testing method is applied with the half omega flexing operation to simulate the practical flexing motion of the hose assembly.

• 융복합기술연구소 논문집
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• 제1권1호
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• pp.24-28
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• 2011

The purposes of this study are predictions of the changes in the section geometry and determination of the initial cross section so that opposite side in height direction is exactly parallel after coiling process. Finite element analysis is carried out for the calculation of the sectional changes for mold spring item. Analysis results reveal that the slope of the top and bottom sides varies in the range of 5 to 8 degrees and the amount depends on the dimension of the outer diameter. The slopes of the sides should be defined first among design variables.

• Journal of Korean Neurosurgical Society
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• 제53권6호
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• pp.383-385
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• 2013

We present an unusual case of peritoneal catheter migration following a ventriculoperitoneal shunt operation. A 7-month-old infant, who had suffered from intraventricular hemorrhage at birth, was shunted for progressive hydrocephalus. The peritoneal catheter, connected to an 'ultra small, low pressure valve system' (Strata$^{(R)}$; PS Medical,Gola, CA, USA) at the subgaleal space, was placed into the peritoneal cavity about 30 cm in length. The patient returned to our hospital due to scalp swelling 21 days after the surgery. Simple X-ray images revealed total upward migration and coiling of the peritoneal catheter around the valve. Possible mechanisms leading to proximal upward migration of a peritoneal catheter are discussed.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.375-380
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• 2006

Embedded Duct Ventilation System in Ondol is embedded supply duct in Ondol. This system allows heat up outside air to inside temperature with out using heat exchanger and electric heating coiling in winter season. In this research, we measured temperature of inside and surface of Ondol, supply duct, and supply air temperature incorporate embedded duct ventilation system in Ondol in model house($110m^2$) & one room($23m^2$)