• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.9
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• pp.822-829
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• 2015

In this paper, the piezoelectric-hydraulic pump with a piezostack actuator as a driving source has been designed, fabricated, and evaluated for its application to UAV's brake system. The performance requirements of the piezoelectric-hydraulic pump were decided based on the requirements analysis of the target aircraft brake system. The geometric design of the piezoelectric-hydraulic pump to meet the performance requirements of the pump was conducted, and all components of the pump including the spring sheet type check valves were machined with close tolerance. By constructing a test apparatus for the performance check of the piezoelectric-hydraulic pump, the performance characteristics of the pump, such as the outlet flow rate for load-free condition and the outlet oil pressure for closed loop condition, have been evaluated. It has been found by the performance test result that the developed piezoelectric-hydraulic pump satisfies the design requirements effectively.

• Journal of the Korean Institute of Gas
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• v.16 no.6
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• pp.128-135
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• 2012

In this paper, we proposed a system and a scenario to raise efficiency of gas safety management by developing wireless ZigBee communication modules, smart-home gas safety appliances and the system suitable for gas safety. Our designed system consists of a micom gas meter, an automatic extinguisher, sensors, and a wall-pad. A micom-gas-meter monitors gas flow, gas pressure, and earthquake. An automatic fire extinguisher checks combustible gas leaks and temperature of $100^{\circ}C$(cut off) and $130^{\circ}C$(fire). Sensors measure smoke and CO gas. In our novel system, a micom-gas meter cut off inner valve with warnings, an automatic fire extinguisher cut off middle valve and spray extinguishing materials, and sensors generate signals when detecting smoke and CO and then take a next action. Gas safety appliances and sensors automatically takes measures, and transmit those information to a wall-pad. The wall-pad again transmits real time information to server. Users can check and manage gas safety situations by connecting BcN server through web or mobile application. We hereby devised scenarios for gas safety and risk management based on the smart, and demonstrated their efficiency through test applied to filed.

• Journal of Chest Surgery
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• v.12 no.3
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• pp.281-288
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• 1979

For years, physicians and anatomists have been interested in the heart that has one functioning ventricle. Various terms have been suggested for this entity including single ventricle, common ventricle, double-inlet left ventricle, cor biatriatum triloculare, and primitive ventricle. In this report, the term "single ventricle" is utilized as suggested by Van Praagh, and is defined as that congenital cardiac anomaly in which a common or separate atrioventricular valves open into a ventricular chamber from which both great arterial trunks emerge. An outlet chamber, or infundibulum, may or may not be present and give rise to the origin of either of the great arteries. This definition excludes the entity of mitral and tricuspid atresia. An 11 year old cyanotic boy was admitted chief complaints of exertional dyspnea and frequent upper respiratory infection since 2 weeks after birth. He was diagnosed as inoperable cyanotic congenital heart disease, and remained without any corrective treatment up to his age of 11 year when he suffered from aggravation of symptoms and signs of congestive heart failure for 2 months before this admission. On 22nd of May 1979, he was admitted for total corrective operation under the impression of tricuspid atresia suggested by a pediatrician. Physical check revealed deep cyanosis with finger and toe clubbing, and grade V systolic ejection murmur with single second heart sound was audible at the left 3rd intercostal space. Development was moderate in height [135 cm] and weight[28Kg]. Routine lab findings were normal except increased hemoglobin [21.1gm%], hematocrit [64 %], and left axis deviation with left ventricular hypertrophy on EKG. Cardiac catheterization and angiography revealed 1-transposition of aorta, pulmonic valvular stenosis, double inlet of a single ventricle with d-loop, and normal atriovisceral relationship [Type III C solitus according to the classification of Van Praagh]. At operation, longitudinal incision at the outflow tract of right ventricle in between the right coronary artery and its branch [LAD from RCA] revealed high far anterior aortic valve which had fibrous continuity with mitral annulus, and pulmonic valve was stenotic up to 4 mm in diameter positioned posterolaterally to the aorta. Ventricular septum was totally defective, and one markedly hypertrophied moderator band originated from crista supraventricularis was connected down to the imaginary septum of the ventricular cavity as a pseudoseptum of the ventricle. Size of the defect was 3X3 cm2 in total. Patch closure of the defect with a Teflon felt of 3.5 x 4 cm2 was done with interrupted multiple sutures after cut off of the moderator band, which was resutured to the artificial septum after reconstruction of the ventricular septum. Pulmonic valvotomy was done from 4 mm to 11 mm in diameter thru another pulmonary arteriotomy incision, and right ventriculotomy wound was closed reconstructing the right ventricular outflow tract with pericardial autograft of 3 x 4 cm2. Atrial septal defect of 2 cm in diameter was closed with 3-0 Erdeck suture, and atrial wall was sutured also when rectal temperature reached from 24`C to 35.5`C. Complete A-V block was managed with temporary external pacemaker with a pacing rate of 110/min. thru myocardial wire, and arterial blood pressure of 80/50 mmHg was maintained with Isuprel or Dopamine dripping under the CVP of 25-cm saline. Consciousness was recovered one hour after the operation when his blood pressure reached 100 /70 mmHg, but vital signs were not stable, and bleeding from the pericardial drainage and complete anuria were persisted until his heart could not capture the pacemaker impulse, and patient died of low output syndrome 320 min after the operation.

• Journal of Chest Surgery
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• v.12 no.3
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• pp.289-296
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• 1979

For years, physicians and anatomists have been interested in the heart that has one functioning ventricle. Various terms have been suggested for this entity including single ventricle, common ventricle, double-inlet left ventricle, cor biatriatum triloculare, and primitive ventricle. In this report, the term "single ventricle" is utilized as suggested by Van Praagh, and is defined as that congenital cardiac anomaly in which a common or separate atrioventricular valves open into a ventricular chamber from which both great arterial trunks emerge. An outlet chamber, or infundibulum, may or may not be present and give rise to the origin of either of the great arteries. This definition excludes the entity of mitral and tricuspid atresia. An 11 year old cyanotic boy was admitted chief complaints of exertional dyspnea and frequent upper respiratory infection since 2 weeks after birth. He was diagnosed as inoperable cyanotic congenital heart disease, and remained without any corrective treatment up to his age of 11 year when he suffered from aggravation of symptoms and signs of congestive heart failure for 2 months before this admission. On 22nd of May 1979, he was admitted for total corrective operation under the impression of tricuspid atresia suggested by a pediatrician. Physical check revealed deep cyanosis with finger and toe clubbing, and grade V systolic ejection murmur with single second heart sound was audible at the left 3rd intercostal space. Development was moderate in height [135 cm] and weight[28Kg]. Routine lab findings were normal except increased hemoglobin [21.1gm%], hematocrit [64 %], and left axis deviation with left ventricular hypertrophy on EKG. Cardiac catheterization and angiography revealed 1-transposition of aorta, pulmonic valvular stenosis, double inlet of a single ventricle with d-loop, and normal atriovisceral relationship [Type III C solitus according to the classification of Van Praagh]. At operation, longitudinal incision at the outflow tract of right ventricle in between the right coronary artery and its branch [LAD from RCA] revealed high far anterior aortic valve which had fibrous continuity with mitral annulus, and pulmonic valve was stenotic up to 4 mm in diameter positioned posterolaterally to the aorta. Ventricular septum was totally defective, and one markedly hypertrophied moderator band originated from crista supraventricularis was connected down to the imaginary septum of the ventricular cavity as a pseudoseptum of the ventricle. Size of the defect was 3X3 cm2 in total. Patch closure of the defect with a Teflon felt of 3.5 x 4 cm2 was done with interrupted multiple sutures after cut off of the moderator band, which was resutured to the artificial septum after reconstruction of the ventricular septum. Pulmonic valvotomy was done from 4 mm to 11 mm in diameter thru another pulmonary arteriotomy incision, and right ventriculotomy wound was closed reconstructing the right ventricular outflow tract with pericardial autograft of 3 x 4 cm2. Atrial septal defect of 2 cm in diameter was closed with 3-0 Erdeck suture, and atrial wall was sutured also when rectal temperature reached from 24`C to 35.5`C. Complete A-V block was managed with temporary external pacemaker with a pacing rate of 110/min. thru myocardial wire, and arterial blood pressure of 80/50 mmHg was maintained with Isuprel or Dopamine dripping under the CVP of 25-cm saline. Consciousness was recovered one hour after the operation when his blood pressure reached 100 /70 mmHg, but vital signs were not stable, and bleeding from the pericardial drainage and complete anuria were persisted until his heart could not capture the pacemaker impulse, and patient died of low output syndrome 320 min after the operation.

• Journal of Chest Surgery
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• v.36 no.6
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• pp.451-455
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• 2003

In August 2000, the American Heart Association and the European Resuscitation Council published the conclusions of tile International Guidelines 2000 Conference on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care which contains both the new recommendations and an in-depth review. The most important changes in the recommendations according to the authors are discontinuation of the pulse-check for lay people, 500 ml instead of 800∼1,200 ml tidal volume during bag-valve-mask ventilation (FiO2 > 0.4) of a patient with an unprotected airway, unifying correct endotracheal intubation size as 8.0 mm, vasopressin (40 units) and epinephrine (1 mg) as comparable drugs to treat patients with ventricular fibrillation, early prehospital survey and intravenous lysis for patients who have suffered coronary artery syndrome and stroke.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.4
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• pp.708-714
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• 1996

Ethanol production from raw starch was performed using the co-immobilized culture system of Rhizopu japonicus and zymomonas mobilis(R-Z). Glucose Production in immobilized R. japonicus culture was 2-fold higher than that in free cell culture. Ethanol production was 1.67g/L(Yp/s, 0.094) and 6.549/L(Yp/s, 0.38) in R-Z and R-Z 24 culture system, respectively. R-Z system was modified and designated as R-Z 24 system by replacing cotton plug with silicon check valve after 24h fermentation with R-Z system. Optimal substrate concentration for ethanol production in batch culture was 5%(w/v) and ethanol concentration produced was 15.02g/L(Yp/s, 0.36). Ethanol yield(Yp/s, 0.38) in fed-batch culture of 5 times with 2%(w/v) substrate was equal to that in batch culture of 2%(w/v) substrate.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.1
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• pp.60-64
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• 2004

In this paper, we implemented a real-time remote home monitoring system which we have ported the Linux OS and HTTP(Hypertext Transfer Protocol) web server. The GoAhead web server was ported using by ARM cross compiler. And then we used the analog to digital converter ADC0809 for sensing the vii able input signal at widely separated home. We have implemented linux device driver for ADC(Analog to Digital Convertor) and CGI-C(Common Gateway Interface - C language) application program using Client pull method for monitoring real-time changing data. The factor of monitoring is temperature, intensity of illumination and gas's existence. And this system has ability which check the status of out door and gas valve. We have designed the embedded web server system for home emergency monitoring in low cost.

• Journal of the Institute of Convergence Signal Processing
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• v.19 no.1
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• pp.14-19
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• 2018

Recently, the smart health care industry has been rising rapidly and interest and efforts for public health have been greatly increased. As a result, the public does not visit medical specialists and medical facilities, but the desire to check their health condition in everyday life is increased. Therefore, many domestic and foreign companies continuously research and develop wearable devices that can measure body activity information anytime and anywhere And the market. Especially, it is used for heart activity measurement device using pulse wave sensor and electrocardiogram sensor. However, in this study, a monitoring system that can detect cardiac activity using cardiac sounds, heart sound measurement rather than pulse wave measurement and electrocardiogram measurement, was performed and its performance was evaluated. Experimental results confirmed the predictability of cardiac heart rate and heart valve disease during daily living.

• 유체기계공업학회:학술대회논문집
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• 2003.12a
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• pp.143-148
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• 2003

This study was experimentally performed in order to estimate the errors due to the leakage of transmitter gaugelines in the orifice flow meter for natural gas. It would be a serious problem in safety if a large quantity of leak was occurred at the tubes or fittings like valve. But in most cases the safety problems might be rarely happened because the gas leak detectors could be operated in advance and the various kinds of inspection would be also fulfilled periodically. If the leakage was occurred continuously with an undetectable amount at the gaugelines for measuring the pressure or the differential pressure(DP), the amount of leakage might be an error or an unaccounted flow(UAE). In addition if the measuring value of pressure or DP were affected by the leakage, it might also be a measurement error. The experiments were performed to estimate the amount of leakage and to check the DP changes if it exited. First, through the measurement of the air pressure changes in the airtight container connected to a transmitter with gaugelines as the time passed, the amount of leakage causing from the fittings of gaugelines was roughly estimated. As changing the leak position of the gaugeline, the leak was intentionally made to break out. The variance of DP was checked as controlling the extent of leakage and compared to no leak conditions. Consequently, under the normal maintenance conditions, the result represented that the amount of leakage causing from the gaugelines was insignificant and also the DP changes on leakage conditions were too small to cause the errors of measurements.

• Journal of the Korean Institute of Gas
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• v.16 no.4
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• pp.1-7
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• 2012

Systematic safety research by Korea Government has been made to enhance the safety of CNG (compressed natural gas) vehicles since the burst of compressed cylinder of an urban bus in August 9, 2010. This article summarizes some major activities to ensure the safety of CNG vehicles, which covers review of regulation, safety management system including standard of inspection and certification, and training program of inspectors and car mechanics. Specifically, the followings were reviewed; type of CNG cylinder, location of CNG cylinder, material and type of fuel line and vent line, modification of pipeline connection, installation of gas detector, installation of emergency shutdown valve, installation of protecting cover for cylinder, obligations for CNG vehicle filling station. improving periodical inspection, routine test on gas vehicles, training program for engaged in gas vehicles, and designation of safety manager for CNG bus company. This paper suggests how to improve safety of CNG vehicles as a result of review of above mentioned check items.