Spiral Wire 충전 맥동 추출탑의 유동특성연구

최호상,김우식,김병식 연세대학교 산업기술연구소 1980 논문집 Vol.12 No.2

This study was carried out to investigate a dynamic characteristics of solvent extraction system by analyzing holdup and RTD curve of pulse column packed by spiral wire. The experimental results showed that holdup of dispersed phase had influence on pulse velocity and superficial liquid velocity. Particularly, holdup increased in proportion to pulse velocity and continuous phase velocity. And it showed that the experimental value approached the theoretical dispersion model within the low range from 2 to 5. When Pe is 4, the experimental value was to approach the theoretical value by the dispersion model.

直接噴射式 디젤엔진에서 GTL熱料의 EGR率變化에 따른 排出物 特性에 關한 硏究

金秉儁,崔源鶴,柳鍾植,李海喆,車京玉 명지대학교 산업기술연구소 2008 産業技術硏究所論文集 Vol.27 No.-

Recently, altenative fuels are drawing more attentions due to the increasing need for lower emission characteristics and fuel consumption rate in automotive engines. The GTL(gas to luquid) is the one of most favored candidates. It has higher cetane number(more than 75) and almost negligible sulphur and aromatic contents. Therefore, enhanced emission characteristics are expected even in the application in diesel engines without any modification. In this study, the cylinder pressure and heat release, emission characteristics with fuel injection timings are compared between diesel and GTL fuel in the single cylinder diesel engine. Noticeable reduction in PM, THC and CO emission are observed due to lower sulphur and aromatic contents in GTL. Also, the ignition delay decreased due to higher cetane number of GTL , which slightly decreased the amount of NOx emissions. EGR is considered as a most efficient method to reduce the NOx emission. With EGR rates, NOx decreases more for the case of GTL, while the level of THC and CO emissions still remains lower than the case of diesel. With EGR rates, Small size distribution of PM became lager and there amount increased. Bul from all conditions, size distribution of PM for the case GTL was lower than Diesel.

코먼레일 單汽筒 디젤엔진에서 GTL 熱料의 噴射時期 變化에 따른 排出物 特性에 關한 硏究

金秉儁,崔源鶴,柳鍾植,李海喆,車京玉 명지대학교 산업기술연구소 2008 産業技術硏究所論文集 Vol.27 No.-

Recently, alternative fuels are drawing more attentions due to the increasing need for lower emission characteristics and fuel consumption rate in automotive engines. The GTL(gas to luquid) is the one of most favored candidates. It has higher cetane number(more than 75) and almost negligible sulphur and aromatic contents. Therefore, enhanced emission characteristics are expected even in the application in diesel engines without any modification. In this study, the cylinder pressure and heat release, emission characteristics with fuel injection timings are compared between diesel and GTL fuel in the single cylinder diesel engine. Noticeable reduction in PM, THC and CO emission are observed due to lower sulphur and aromatic contents in GTL. Also, the ignition delay decreased due to higher cetane number of GTL , which slightly decreased the amount of NOx emissions. With the retards of main injection timing. NOx decreases more for the case of GTL, while the level of THC and CO emissions still remains lower than the case of diesel. Therefore, there is much room for the control of injection timiing for NOx reduction without sacrificing THC and CO emissions. With the retards of main injection timing, Small size distribution of PM became lager and there amount increased. But from all conditions, size distribution of PM for the case GTL was lower than Diesel.

뉴로-퍼지 논리를 이용한 12경락의 양도락진단 시스템의 구현

김병화,한권상,이우철,김성현,최해성,안현식,김도현 대한전자공학회 1997 秋季綜合學術大會 論文集 Vol.20 No.2

유압식 인버터 제어기의 속도제어를 위한 퍼지기반 하이브리드 슬라이딩모드 제어기 설계

한권상,최병욱,안현식,김도현 제어·자동화·시스템공학회 2003 제어·자동화·시스템공학논문지 Vol.9 No.3

19세기 西進東漸의 파도 속에서 국가의 자립과 근대화를 위해 몸소 힘썼던 兪吉潛과 福澤??論의 사상 가운데 그들의 政淪論을 한국과 일본의 근대화 방향 차이를 중심으로 살펴보고자 한다. Due to the friction characteristics of pump, cylinder packing and passenger car, in the elevation system actuated with hydraulic inverter, there exist dead zones, which cannot be controlled by a PID controller. To overcome the drawbacks, in this paper, we propose a new hybrid fuzzy-sliding mode control scheme, which controls the controller output between a sliding mode control output and a PID control output by fuzzy control method. The proposed hybrid control scheme achieves an improved control performance by using both controllers: We first propose a design method of the hybrid controller for a hydraulic system controlled by inverters, then propose a design method of a hybrid fuzzy-sliding mode control scheme. The effectiveness of the proposed control scheme is shown by simulation results, in which the proposed hybrid control method yields better control performance then the PID controlled scheme, not only in the zero-crossing speed region but also in the overall control region including steady-state region.

PMDA-ODA 폴리이미드의 합성 및 특성에 관한 연구

정용재,한태성,최성부,남석태,김병식 동국대학교 산업기술연구원 1996 산업기술논문집 Vol.8 No.-

Pyromellitic dianhydride(PMDA) 와 Oxydianiline(ODA)를 N, N-dimethylacetamide (DMAc)에 녹여 Polyamic acid(PAA)를 2단계 열이미드화법으로 제조하였다. 제조된 폴리이미드 막의 이미드화도는 FT-IR에 의하여 분석되었다. 또한 PAA의 농도를 10~30wt%로 변화시키며 합성하여 열이미드화 시킨 후 농도에 따른 단면의 상태를 SEM사진을 통하여 관찰하였다. 농도 변화에 따른 밀도와 T_g의 변화는 혼합액체부상법과 DSC로 분석되었다. 열처리 온도를 증가시킬수록 이미드화도는 증가되었고 PAA의 농도가 증가할수록 필름의 단면이 치밀해짐을 알 수 있었다. 또한 제조된 PMDA-ODA 폴리이미드의 T_g는 215℃ 이었다. Polyamic acid(PAA) was synthesised with Pyromellitic dianhydride(PMDA) and Oxydianiline (ODA) in N, N-dimethylacetamide(DMAc). PMDA-ODA polyimide membranes were obtained by two step thermal imidization, and the degree of imidization of polyimide membranes was observed by the FT-IR. After the thermal imidization through the concentration of varied synthesis of PAA, 10~30wt%, SEM photographies of section state were observed. The density and glass transition temperature on the varied concentration were replace with investigated test of density and Differential Scanning Calorimetry (DSC). With increasing thermal treatment temperature, the degree of imidization was increased. While the concentration of PAA increases, the section of membrane was densed. The glass transition temperature was maintained to be constant(215℃) within the PAA concentration range.

폐동맥고혈압 환자에서 우심실압 파형과 폐동맥압의 혈관확장제에 대한 반응성의 관계

이준희,김용진,손대원,오병희,이병묵,박영배,최윤식 대한순환기학회 2003 Korean Circulation Journal Vol.33 No.11

액체소듐속에서 소듐-물반응에 의한 재질의 Wastage현상

정경채,정지영,김병호,김태준,최병해,최종현,김의식 한국공업화학회 2003 응용화학 Vol.7 No.1

In this study we observed and analyzed the corrosion phenomena in leak site and the effect on temperature at the target surface of heat transfer tube material by sodium-water reaction through water leakage in liquid sodium atmosphere. Surrounding of leak hole of the specimen was damaged by the wastage phenomena due to corrosion and erosion of material, and hole size by damage of leak site was extended from 150㎛ to about 200㎛. Also, the damaged size appeared in the target surface was observed to about 1000㎛ diameter. The temperature of target surface increased about 70~80℃ by the heat of sodium-water reaction even with the small leakage of 15㎖ water. From the results of EPMA and EDX analysis, damaged area are found to covered with complex compounds such as (NaOH+Na_2O) FexOy or (NaCrO_2+nA_2CrO4) mixed up with the sodium oxides by sodium-water reaction and the Fe or Cr element by matrix of tube sodium oxides by matrix of tube material.

A Study on Loading Arm Envelope and Alarm Setting according to Ship Movement

Choi, Byoung-Yeol,Jo, Hyo-Jae,Choi, Han-Sik,Choi, Dong-Eon Korean Society of Ocean Engineers 2018 Journal of advanced research in ocean engineering Vol.4 No.3

This study was carried using the new approach method to design appropriately the Loading Arm length and the alarm setting according to ship movements on Loading and Unloading marine Berth. The quasi-static mooring analysis was performed to estimate 110,000DWT ship's movements based on environmental conditions such as wind, current and wave. The mooring motion of the ship is very important to determine the loading arm scope, and in this case, the operation condition is performed on the ship without considering the damaged condition of the mooring line because the ship movement in case of damage is larger than intact, and all operations are stopped, the loading arm being released due to control system. From the result of mooring analysis, motion displacements, velocities and accelerations were simulated. They were used to simulate the maximum drifting speeds and distances. The maximum drifting speeds were checked to be satisfied within drifting speed limits. The total maximum drifting distances were simulated with alarm steps of the new approach method. Finally, the loading arm envelopes using the total maximum drifting distances were completed. Therefore, it was confirmed that the new approach method for loading arm envelopes and alarm settings was appropriate from the above results. In the future, it will be necessary to perform the further advanced dynamic mooring analysis instead of the quasi-static mooring analysis and to use the precise computer program analysis for various environments and ship movement conditions.

Carbonation of Sodium Carbonate and Calcination of Sodium Bicarbonate

Choi, Byoung-Sik,Sung, Duck-Ho,Oh, Kwang-Joong,Moon, Kil-Ho,Park, Sang-Wook 한국공업화학회 2005 응용화학 Vol.9 No.1

Sodium carbonate has been employed for a chemical absorption method to capture carbon dioxide from the mixture of carbon dioxide, nitrogen, and moisture. Sodium carbonate reacts with both carbon dioxide and moisture to form sodium bicarbonate by the carbonation, followed by the calcinations of sodium bicarbonate to release carbon dioxide on flushing with nitrogen to shift the reaction in reverse. A fixed bed was used to observe the breakthrough curves of carbon dioxide, which were used to obtain the reaction rate constants(carbonation rate constant and calcination rate constant) of both reactions from comparison of experimental values with simulated values. Dependence of the reaction rate constants on the reaction temperature was observed using the Arrhenius plots.