• Journal of Mechanical Science and Technology
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• v.20 no.9
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• pp.1483-1491
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• 2006

The pumping performance of molecular drag pumps (MDP) has been investigated experimentally. The exporimented MDPs are a disk-type drag pump (DTDP), helical-type drag pump(HTDP) and compound drag pump (CDP), respectively In the case of the DTDP, spiral channels of a rotor are cut on both upper surface and lower surface of a rotating disk, and the corresponding stator is a planar disk. In the case of the HTDP, the rotor has six rectangular grooves. The CDP consists with the DTDP, at lower part, and with the HTDP, at upper part. The experiments are performed in the outlet pressure range of $0.2{\sim}533Pa$. The inlet pressure and compression ratio are measured under the various conditions of outlet pressure and throughputs, and nitrogen is used for the test gas. At the outlet pressure of 0.2Pa, the ultimate pressure has been reached to $1.0{\times}10^{-2}Pa$ for the HTDP, $1.3{\times}10^{-4}Pa$ for the DTDP, and $3.6{\times}10^{-5}Pa$ for the CDP. The maximum compression ratio of the CDP is much higher than those of the DTDP or HTDP. Consequently, the ultimate pressure of the CDP is the lowest one.

• Journal of Chest Surgery
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• v.12 no.3
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• pp.225-232
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• 1979

A 15-year-old girl underwent successful surgical correction of double-outlet right ventricle [S.D.L.] subaortic ventricular septal defect, patent foramen ovale, and pulmonary hypoplasia with valvular stenosis. The operation consisted of an internal baffling connecting the left ventricle to the aorta through the ventricular septal defect. The pulmonary stenosis was corrected with the method of connection the right ventricle to the pulmonary artery bifurcation using the Hancock valve[18mm] contained conduit. This rare type of DORV seemed to be suitable for corrective surgery, and the patient`s condition is very good until present time (post operative 7 months).

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.5
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• pp.59-66
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• 2013

Lack of the space in many diesel vehicles make it difficult to design and install the catalytic muffler to reduce emissions. For this reason, inlet part of the catalytic muffler is made of L-type which has lower flow uniformity than conventional I-type, and catalytic muffler has complex internal structure by various insertions, which affect the flow uniformity and pressure drop of the systems. In this work, the flow characteristics such as flow uniformity and pressure drop have been numerically investigated by changing such various geometries as inlet shape, porosity, and outlet shape inside the muffler with the three-dimensional turbulent incompressible flow solver. Total 4 different cases are considered in order to find optimal configurations of the catalytic muffler in view of high flow uniformity and low pressure drop. The results show that Case 2 which has no induction cone and outlet perforated pipe has higher uniformity index and lower pressure drop than others considered in this work.

• Journal of the Korean Operations Research and Management Science Society
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• v.38 no.1
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• pp.183-199
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• 2013

This study investigates customers' different behavior in accumulating and redeeming points and focuses on the moderating effect of usage level. We measure the hedonic accumulation and redemption ratio and usage level using loyalty program transaction data and link them to the survey data of loyalty and satisfaction. By doing so, we examine the effects of hedonic accumulation and redemption ratio on a consumer's loyalty intention and his or her satisfaction and the moderating effect of usage level. The result shows that there is a significant positive effect of hedonic accumulation and redemption ratio on customer loyalty and the mediating role of satisfaction on customer loyalty in both stages. And accumulation and redemption most importantly, we find an interaction effect of usage level on outlet type in point redemption stage while no effect in accumulation stage. That is if customers accumulate and redeem points at a hedonic outlets in both stages, it will give him a feeling of satisfaction and finally it will enhance the loyalty toward the focal loyalty program. And light buyers' loyalty increase more than those of heavy buyers when they redeem points in hedonic outlet. Our findings will help marketing managers of loyalty program to apply the effective segmentation strategy to the reward program which affects the customer's satisfaction and loyalty.

• Journal of the Korean Society of Propulsion Engineers
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• v.20 no.3
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• pp.103-110
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• 2016

A performance analysis program of a disk type fluidic valve was developed to predict a chamber pressure and a response time. A parametric study of this device was performed by using scattering plot method. A sensitivity of Mach number at a nozzle outlet showed the highest value about a outlet diameter of nozzle. An inlet flow rate is the most important parameter to design the fluidic valve because it has high sensitivity value both a outlet velocity and a response time.

• Journal of Chest Surgery
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• v.48 no.2
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• pp.146-150
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• 2015

Arterial thoracic outlet syndrome (TOS) causes ischemic symptoms; it is the rarest type, occurring in 5% of all TOS cases. This paper is a case report of a 38-year-old male patient diagnosed with arterial TOS, displaying symptoms of acute critical limb ischemia caused by thromboembolism. Brachial artery of the patient has been diffusely damaged by repeated occurrence of thromboembolism. It was thought to be not enough only decompression of subclavian artery to relieve the symptoms of hand ischemia; therefore, bypass surgery using reversed great saphenous vein was performed.

• Journal of Veterinary Clinics
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• v.33 no.5
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• pp.307-309
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• 2016

A 10-month-old intact male Scottish Fold was presented with cardiomegaly. The cat showed exercise intolerance after birth. Radiographs showed cardiomegaly with bulging of the main pulmonary artery and dilation of pulmonary arteries. Echocardiogram revealed abnormally arisen aortic root toward right ventricle with left-to-right shunted perimembraneous ventricular septal defect located underneath the aortic root. Based on imaging studies, the cat was diagnosed as subaortic type of double outlet right ventricle (DORV) without concurrent abnormalities.

• Nuclear Engineering and Technology
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• v.53 no.7
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• pp.2207-2220
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• 2021

Lead alloy is used as coolant in Lead-based cooled Fast Reactor (LFR). The natural characteristics of lead alloy are combined with the simple structural design of LFR. This constitutes the inherent safety characteristics of LFR. The main work of this paper is to take the main coolant pump (MCP) in the lead-cooled fast reactor (LFR) as the research object, and to study the flow pattern distribution of the internal flow field under the reverse rotation pump condition, the reverse rotation positive-flow braking condition and the reverse rotation negative-flow braking condition. In this paper, the double-outlet volute type and the space guide vane are selected as the potential designs of the CLEAR-I MCP. In this paper, the CFD method is used to study the potential reverse accident of the MCP. It is found that the highest flow velocity in the impeller appears at the impeller outlet, and the Q-H curves of the two design programs basically coincide. The space guide vane type MCP has better hydraulic performance under the reverse rotation positive-flow condition, the Q-H curves of the two designs gradually separate with increasing flow rate, and the maximum flow velocity inside the space guide vane type MCP is obviously lower than that of the double-outlet volute type. For the reverse rotation test of MCP, only the condition of the forward rotating pump of the main coolant pump is tested and verified. For the simulation of the MCP in LBE medium, it proved that the turbulence model and basic settings selected in the simulation are reliable.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.6
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• pp.748-754
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• 1999

The acoustic performance of reactive type single expansion chamber can be calculated theoretically by plane wave theory. But higher order modes should be considered to widen the frequency range. Munjal has suggested the method for analyzing the acoustic properties of simple expansion chamber with taking into consideration of higher order mode of inlet/outlet. But his method cannot predict the acoustic properties exactly when the dimensions of inlet/outlet and expansion chamber have not integer multiples. In this paper the new method was suggested to overcome the shortcomings of Munjal's method The predictions by this method were also compared with those by the finite element method.

• Journal of Chest Surgery
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• v.21 no.2
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• pp.326-333
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• 1988

The results of surgical experience of double outlet right ventricle with pulmonic stenosis in 14 patients are reported. Among the 14 patients, 8 underwent the intraventricular tunnel repair with the result of 3 hospital deaths, 5 had Fontan type operations due to the various anatomic reasons and resulted in one hospital death, and the remaining one patient had palliative pulmonary valvotomy. Besides the problems related to the effective relief of the pulmonic stenosis, double outlet right ventricle with pulmonic stenosis may present a surgical challenge because severe associated anomalies which definitely complicate their repair are not uncommon. We describe the anatomic details of our 14 cases of DORV with PS and the surgical results. The results having been unsatisfactory, more meticulous diagnostic studies for the detailed intracardiac morphologies and the strict indication for their repair with the refinement of surgical technique seem necessary for the better surgical results.