http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
수학적 모델링 방법에 기초한 복합발전 공정의 정상상태 모사시스템 개발
김신혁 ( Shin Hyuk Kim ),이시황 ( Lee Si Hwang ),주용진 ( Yong Jin Joo ),이상욱 ( Sang Uk Lee ),손병모 ( Byung Mo Shon ),오민 ( Min Oh ) 한국화학공학회 2015 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.53 No.5
복합발전 공정의 모델링 및 모사는 공정의 운전 및 설계 조건에 따른 공정변수의 변화를 정량적으로 예측하기 위한 중요한 접근방법이다. 본 연구에서는 현재 사용되는 복합발전공정의 정상상태 모사기의 단점을 보완하여, 사용자의 편의성과 개발자의 핵심기술 모델링을 가능하게 하는 공정 모델링 시스템을 개발하였다. 복합발전 공정의 주요 장치들을 분석하여 수학적 모델을 개발하였으며 이를 종합하여 모델라이브러리로 구성하였다. 또한 모사의 목적과 입수 가능한 자료에 따라 사용되는 모델의 상세도가 다르다는 점을 고려하여 주요장치에 대해 다른 상세도의 모델을 개발하였다. 복합발전 상업공정을 개발된 모델링 시스템을 사용하여 모델링과 모사를 수행하였으며 모사의 결과를 데이터자료와 비교 검증하였다. 검증의 모사결과와 자료데이터는 1% 내의 오차를 보였으며 개발된 모델링 시스템이 실제 공정에 응용될 수 있음을 보여주었다. Process modeling and simulation is a powerful methodology to quantitatively predict the change of processvariables when operating and design conditions are changed. In this study, considering drawbacks of currently used process simulator for combined cycle plants, we developed process modeling system equipped with an ease of use and flexibility for model development. For this purpose, the analysis of combined cycle processes was carried out and consequently, mathematical models and libraries were developed. Furthermore, in view of the fact that the level of the abstraction of process models depends on the purpose of simulation as well as the available data, simple and rigorous models were also developed for some important units. In use of reference combined plant, we executed process simulation using the developed modeling system and the comparison was made between the results of simulation and the reference data. Less than 1% marginal error was identified and we concluded that the modeling system can be applied forcommercial combined cycle processes.
복부 초음파 검사 보편화 시대의 소아 장중첩증의 임상적 고찰 - 소장형과 대장형의 비교 -
김완성,정진호,이종훈,박재균,문현종,신혁재,이종인,Kim, Wan-Sung,Jeong, Jin-Ho,Lee, Jong-Hoon,Park, Jae-Kun,Moon, Hyoun-Jong,Shin, Hyuk-Jai,Lee, Jong-In 대한소아외과학회 2011 소아외과 Vol.17 No.1
We analyzed the clinical characteristics and outcome of ileocecal and small bowel intussusceptions (ICI and SBI) in the pediatric patients. From August 2003 to July 2010, 144 children with intussusception were included in this study. We retrospectively reviewed the clinical records and Imaging study findings. A total of 86 children with ICI and 58 children with SBI were diagnosed. Children with SBI were older than ICI ($36.6{\pm}24.6$ months vs. $24.2{\pm}21.6$ months, p=0.002). Typical symptoms such as irritability, abdominal mass, bloody stool were more frequent in ICI than SBI (p<0.05) patients. In the ICI group, intussusceptums were reduced with air reduction (84.5%), surgery (17.4%), and spontaneity (1.2%). All patients in the SBI group were reduced spontaneously. SBI occurred in older age and was reduced spontaneously more frequently than ICI. Conservative management with close observation with follow-up by ultrasonography is recommended for SBI.
김대열,한영출,조재명,김양술,주신혁,박병완 한국공작기계학회 2003 한국공작기계학회 추계학술대회논문집 Vol.2003 No.-
An experimental study presents characteristics of combustion in a combustion chamber by port deactivation valve for economy and emissions standards. In order to use combustion properties data, it is necessary to build some data base, which use cylinder pressure sensor, etc. Port deactivation valve has been developed to satisfy requirement of achieving sufficient swirl generation to improve the combustion. A feasibility and necessity of combustion pressure based cylinder spark timing control has been examined. So, this was obtained the Coefficient of Variation(COV) and the mass-burned(MFB). The characteristics of pressure ratio fraction is similar to that of mass-burned fraction. Using the results of the test, the effects of the combustion chamber can be improved combustion stability by port deactivation.