http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
연구논문 : 실측 파형과 수치 파형에 의한 진동주응력 비교
홍웅기 ( Woong Ki Hong ),송정언 ( Jeong Un Song ),박영민 ( Young Min Park ) 한국환경영향평가학회 2012 환경영향평가 Vol.21 No.5
In recent years, the development of computer technique was possible to the simulation analysis of the structure caused by ground vibration. Generally, finite element method(FEM) has been used in these structural analysis. In this study, it was calculated to the vibration energy as measuring vibration waveform, and estimated about principal stress due to medium characteristics of the ground as processing dynamic analysis by the vibration energy. The results are as follows: Firstly, the principal stress distribution in all mediums was different due to a medium condition, and the principal stress at concrete medium was represented to difference due to physical characteristics. Secondly, the principal stress by time increasing was represented to maximum amplitude within 0.03 second. And also, the principal stress after maximum amplitude was very large at concrete medium, which was considered to be formed compression or tension range at a medium boundary. Thirdly, the variation of principal stress at concrete medium was represented in the order of RC medium, NC=H medium, NC=S medium. It was considered that the vibration energy propagated fast when a medium have a big elasticity and density.
기본 ORC와 재생과정을 적용한 ORC의 효율 비교에 관한 열역학적 해석 연구
홍웅기(Woong-Ki Hong),김정민(Jung-Min Kim),박창용(Chang-Yong Park) 대한설비공학회 2011 대한설비공학회 학술발표대회논문집 Vol.2011 No.7
The present study was conducted on thermodynamic efficiency of basic and regenerative Organic Rankine Cycle. R113, R123, R245fa, R245ca and Isobutane were adopted as working fluids. 2 types of regenerative ORCs, one with an open feed water heater, and the other with a regenerator were analyzed. The working fluids except R113 showed that the ORC with FWH had higher efficiency than the basic and regenerative ORC with a regenerator. Regenerative ORC that applied feed water heater shows the highest efficiency among three systems.
급액가열기, 재생기를 적용한 유기랭킨사이클(ORC)의 열역학적 효율에 관한 해석적 연구
박창용(Chang Yong Park),홍웅기(Woong-Ki Hong),김정민(Jung-Min Kim) 대한설비공학회 2011 설비공학 논문집 Vol.23 No.10
A numerical study was performed for thermodynamic efficiencies of a basic ORC (Organic Rankine Cycle), ORC with a FLH (Feed Liquid Heater), and ORC with a regenerator. The efficiencies of the basic ORC were higher in the order of R113, R123, R245ca, and R245fa for its working fluids. It was confirmed that an optimal FLH pressure existed to maximize efficiency of the ORC with a FLH. A correlation was developed to predict the optimal FLH pressure as a function of evaporation and condensation pressure and its average absolute deviation was 0.505%. The efficiency enhancement of the basic ORC with a FLH was higher than that with a regenerator. It was presented that the basic ORC efficiency could be improved more than 10% by a FLH with 30℃ condensation and over 110℃ evaporation temperatures.
송정언 ( Jeong Un Song ),홍웅기 ( Woong Ki Hong ),김승곤 ( Seung Kon Kim ) 한국환경영향평가학회 2011 환경영향평가 Vol.20 No.5
The ground vibration has effect on the human body and the nearby structure. However, it was very difficult to estimate the damage of structure caused by the vibration. Especially, ground vibration must be estimated on the bottom of structure because it was made up of several mediums. In this study, it was considered about the shock vibration on medium characteristics as calculating the peak particle velocity and analysing the vibration waveform. The results are as follows: Firstly, the correlation coefficient of PPV(Peak Particle Velocity) and SD(Scaled Distance) was very high at the vertical component, which was represented to 0.991 in general ground medium and each 0.989, 0.961, 0.925 in concrete medium. And also, the vibration waveform at the vertical component was very good in all mediums. Secondly, the vibration waveform at the longitudinal component was represented to a great amplitude and phase difference in all mediums. It was considered that the vibration waveform occurred the damping when particle velocity by shock vibration was propagated through other medium. Thirdly, the vibration waveform in concrete medium was represented to variation of amplitude in the order of RC medium, NC=H medium, NC=S medium at the vertical component. It was considered that the particle velocity propagated fast when a medium have a big strength and density.
송정언 ( Jeong Un Song ),홍웅기 ( Woong Ki Hong ),김승곤 ( Seung Kon Kim ) 한국환경영향평가학회 2012 환경영향평가 Vol.21 No.2
The shock vibration such as machine vibration, blasting vibration etc. has effect on nearby structure as well as human body. The purpose of this study is to predict allowable limit distance of vibration about human body. First of all, vibration velocity such as PPV, PVS was measured by shock vibration experiment, and vibration level was calculated by conversion formula of vibration velocity. And then, allowable limit distance was analyzed by converted vibration level. The results are as follows : Firstly, the correlation coefficient of converted vibration level was over R=0.94, and vibration level caused by PVS was usually represented to high curve line. Secondly, the cross point of vibration level between ground and concrete condition was represented to 66.68dB(V), and allowable limit distance was represented to difference over three times when vibration regulation was raised from 65dB(V) to 80dB(V).
고전압 임펄스를 활용한 발전용수 칼슘농도 저감에 관한 연구
김태희(TaeHui Kim),장인성(In-Soung Chang),정재환(Jae-Hwan Jung),홍웅기(Woong ki Hong),이준호(June-Ho Lee) 대한전기학회 2017 전기학회논문지 Vol.66 No.3
As an alternate technique for water softening, high voltage impulse (HVI) is introduced and verified if it can control the CaCO3 scale formation in industrial water treatment. After HVI was applied to the artificial hard water containing 100±5 mg/L Ca2+ for 4 hours, the Ca2+ concentration and the electrical conductivity were measured. The concentration of Ca2+ was reduced from 94.5 to 86.3 mg/L (8.7% reduction) after 4 hour contact of HVI under 5 kV condition. The Ca2+ was decreased from 92 to 77.7 mg/L (15.6% reduction) at 8kV and from 90.1 to 75.4 mg/L (16.3% reduction) at 12 kV condition. Both of the contact time and the applied voltage were important parameters affecting the calcium ion reduction. With these results, it was verified that HVI technique could be potential candidate for control of CaCO3 scale formation.