• Applied Chemistry for Engineering
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• v.27 no.5
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• pp.508-511
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• 2016

A facile synthesis of 4-(aminomethyl)cyclohexanecarboxylic acid (AMCA) from recyclable methyl 4-formylbenzoate (MFB) was described. In particular, we investigated the best process variables such as catalyst, hydrogen pressure, reaction temperature, and reaction time for AMCA conversion from AMBA through hydrogenation reaction. The best conditions were found to be as follows: the catalyst as [5% Pd/C, 5% Pt/C, 5% Rh/C (1 : 1 : 1)] which is a composite catalyst, the pressure as 30 bar, the reaction time as 8 hours and the reaction temperature at $130^{\circ}C$. Under the condition, a 90% yield (purity 99.9%) for the mass production of AMCA was achieved.

• Journal of Korean Neurosurgical Society
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• v.30 no.9
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• pp.1065-1071
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• 2001

Object : This study was conducted to evaluate whether short-term intravenous infusion of tranexamic acid (AMCA) was able to improve the management outcome by preventing rebleeding without increasing vasospasm and hydrocephalus associated with the long-term administration of this agent in the patients with aneurysmal subarachnoid hemorrhage(SAH) who were planned for the early surgery. Methods : During the period from June, 1996 to May, 1998, 137 patients admitted within 3 days of their SAH and planned for early surgical intervention were subject to study population. Of these, 60 patients who had been treated with AMCA were classified as AMCA treated group and 77 patients without AMCA treatment as AMCA untreated group. Initially, prognostic factors for rebleeding, vasospasm, hydrocephalus and outcome following SAH including age, sex, clinical grade, CT grade, site of ruptured aneurysms, admission day after SAH, surgery day after SAH, number of aneurysms and hypertension history, were analyzed and compared between AMCA treated group and untreated group. Secondly, the incidence of rebleeding, symptomatic vasospasm and hydrocephalus were compared between the two groups. Also, the management outcome of the patients was compared between the two groups. Results : There were no significant differences in prognostic factors between the two groups. The rebleeding rate was 0% in the AMCA treated group whereas the rate was 7.8% in the untreated group. This difference was statistically significant. The incidences of symptomatic vasospasm and hydrocephalus were found not to be significantly different between the two groups. Of the treated group, 31.7% of patients developed hydrocephalus compared to 32.5% of those at the untreated group. Fourteen(23.3%) patients in treated group developed symptomatic vasospasm and 6 of them(10%) suffered stroke whereas incidences of these in untreated group were 25.9% and 11.7%, respectively. The AMCA treated group showed more favorable outcome than that of untreated group. There was no case of death by rebleeding in the AMCA treated group while one of the main causes of death in the untreated group was rebleeding. Conclusion : Short-term high-dose AMCA administration is considered beneficial in improving outcome and diminishing the risk of rebleeding in the patients who suffer from an aneurysmal SAH prior to early surgical intervention.

• 유체기계공업학회:학술대회논문집
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• 2005.12a
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• pp.67-70
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• 2005

• The KSFM Journal of Fluid Machinery
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• v.8 no.5 s.32
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• pp.29-34
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• 2005

In this study, the effect of flow settling means on the performance of fan tester were numerically investigated by using a computational fluid dynamics (CFD). The airflow rate was calculated from the pressure differential across a flow nozzle in the measuring plane and the flow settling means were generally installed in the chamber of the fan tester to provide proper airflow patterns ahead of the measuring plane. The predicted nozzle differential pressures with uniform inlet velocities were compared with the values of the ANSI/AMCA 210-99 to verify the performance of the commercial CFD code CFX 5.6. The influence of flow settling means on the measurement of airflow rate in a fan tester were discussed with various porosities and inlet jet velocities. The results obtained show that the proper band of porosities exist to meet the AMCA standard in a specified inlet jet velocity.

• The KSFM Journal of Fluid Machinery
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• v.9 no.4 s.37
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• pp.43-48
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• 2006

In this study, the effect of flow settling means on the performance of fan tester were numerically investigated by using a computational fluid dynamics(CFD). The airflow rate was calculated from the pressure differential across a flow nozzle in the measuring plane and the flow settling means were generally installed in the chamber of the fan tester to provide proper airflow patterns ahead of the measuring plane. The predicted nozzle differential pressures with uniform inlet velocities were compared with the values of the ANSI/AMCA 210-99 to verify the performance of the commercial CFD code CFX 5.6. The influence of flow settling means on the measurement of airflow rate in a fan tester were discussed with various porosities and inlet jet velocities. The results obtained show that the proper band of porosities exist to meet the AMCA standard in a specified inlet jet velocity.

• 유체기계공업학회:학술대회논문집
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• 2003.12a
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• pp.373-378
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• 2003

In this paper, build up of fan performance tester in KITECH was introduced. The fan tester was set up based on AMCA standards 210-99, ANSI/ASHRAE 51-1999 with maximum flowrate within $1000\;m^{3}/min$. Both of inlet and outlet chamber setup with multiple nozzles described in AMCA 210 were established. The development of fully automatic control and measurement system are described. With this system, the accuracy of fan performance test can be maintained through the various flowrate and the uncertainty can be reduced.

• The KSFM Journal of Fluid Machinery
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• v.17 no.2
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• pp.24-29
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• 2014

In general, a large-capacity axial flow fan is used for industrial processes or ventilation in a social overhead capital infrastructure. The main characteristics of the large axial-flow fan need a lot of electrical power consumption and operate 24 hours a day, 365 days a year. Since the large axial flow fan consumes several hundreds to thousands kW per hour, both manufacturer and consumer are struggling to select high efficiency products for saving energy and reducing operation cost. Therefore, the performance testing should be accurately conducted in experimental equipments. The performance estimation and uncertainty of measurement of the axial-flow fan gathered from the result from nozzle shaped testing equipments certified with ANSI/AMCA standard and duct shaped testing equipment under the same experimental condition. The experimental results from both facilities have maximum 17% differences in performance evaluation and uncertainty of measurement. As considering that the differences, it is doubt about the reliability of testing result. The test was repeated with the specific term during 12 months because it is important to fully reflect the real conditions and to decide the repeatability of data. The evaluation of duct type testing facilities was failed to get an uncertainty measure. Testing results were previously published. As a series of previous paper, axial fan (∅1690 mm) and duct type testing facilities were fabricated. The purpose of fabricating testing equipment was testing an uncertainty measurement under the controlled environments.

• Journal of Korean Neurosurgical Society
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• v.45 no.5
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• pp.289-292
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• 2009

Objective : Although there are several descriptions of this vessel, there is no detailed angiographic study of the accessory middle cerebral artery (AMCA) in Korea. We describe the angiographic characteristics of the cortical territory and origin of AMCA and discuss the clinical significance of this anomaly. Methods : We searched for patients with AMCAs from a retrospective review of 1,250 conventional cerebral angiograms. We determined the origins, diameters and cortical territories of these AMCAs. Results : Fifteen patients (15 of 1250 = 1.2%) had 16 AMCAs (one patient had bilateral AMCAs). AMCAs originated from the distal A1 in eleven cases, middle A1 in two, proximal A1 in two, and proximal A2 in one case. All AMCAs followed a course parallel to the main middle cerebral artery (MCA). All but three of these arteries were smaller than the main MCA. Thirteen of the smaller diameter AMCAs had cortical distribution to the orbito-frontal and prefrontal, and precentral areas. Three AMCAs had diameter as large as the main MCA. These three supplied the orbito-frontal, prefrontal, precentral, central and anterior-parietal arteries. Conclusion : The AMCAs originated from A1 or A2. Most had smaller diameter than the main MCA. The AMCAs coursed along the horizontal portion of the MCA, but supplied the orbital surface, the anterior frontal lobe and sometimes wider cortical territory, including the precentral, central, anterior-parietal areas.

• Fire Science and Engineering
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• v.23 no.3
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• pp.131-137
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• 2009

This study measured smoke control damper leaking amount of condition of various kinds examination regarding AMCA Standard 500-D-98. As result of study establish because smoke control damper leaking amount performance curve that use tester data of engineering applies right design method of smoke control system and test method design, drawing examination, performance test and do so that right comprehension and performance about skill may be defined. Also user wishes to prove performance of smoke control system and construct smoke control system of reliable performance-based design derive smoke control damper quality improvement continuously selection of smoke control damper by performance judgment of performance curve.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.10a
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• pp.143-149
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• 2009

Recently, according to the tendency to the more comfortable automobile, the improvement of performance of the cooling fan is required. The performance of cooling fan is affected by many peripheral parts, such as radiator, condenser, engine block and etc. Therefore, it is important to consider the effect of peripheral components on the fan performance in design and analysis stages. In this paper, the performance of automobile cooling fan is investigated experimentally by using the large capacity fan tester based on the ASHRAE and the AMCA standards. In particular, the various spacing between cooling fan and engine block are considered to obtain the effect of engine block. An empirical relation between the fan flow rate and the spacing was proposed.