에탄올 탈수 PSA 공정의 전산 모사 및 설계 최적화 연구

박융호,최재식 漢陽大學校 工學技術硏究所 1997 工學技術論文集 Vol.6 No.1

A model for scale-up of PSA process of ethanol dehydration was established using bench experimental data. LDF mass-transfer model, Langmuir adsorption isotherm and single-component adsorption were assumed in the model and the coefficients for heat and mass transfer in the beds were fitted against the experimental data. Model equations were solved using a DAE solver (Speed Up). The effects of cycle time, P/F ratio, adsorption pressure, bed length were examined, and the dimension and the operating condition which give optimum peformance for a commercial process were determined.

Ti(C,N) 코팅에 의한 SKD11강의 내마모성 개선 연구

박재용,김흥식 울산대학교 2000 공학연구논문집 Vol.31 No.1

코팅층의 밀착력을 향상시킬 목적으로 SKD11강을 플라즈마 질화하여 질소 확산층을 형성하고, 그 위에 PACVD법으로 TiN및 Ti(C,N)코팅층을 형성시키는 연구를 수행하였다. PACVD공정에서 메탄(CH₄) 가스의 유입량이 증가되면 코팅층 두께와 경도는 증가하는 경향을 보였지만 내마모성을 감소하는 경향을 보였다. 메탄(CH₄) 가스와 유입량이 2vol.% 일 때 최대 임계박리 하중은 54N을 얻을 수 있으며 이때 코팅층의 두께는 2㎛이고 경도는 650Hv(50g 하중)이다. Ti(C,N)코팅층의 탄소와 질소 농도는 표면쪽에는 탄소가, 코팅층과 소재사이 경계면에는 질소의 농도가 높은 즉, 농도가 경사진 코팅층이 형성되었다. 코팅층의 경도와 임계박리 하중은 공정중의 템퍼린 효과 때문에 강의 템퍼링 온도에 무관하며 강의 표면조도는 코팅층의 조도, 경도 및 내마모성에 영향을 주지 않았다. The formation and characterization of TiN or Ti(C,N) coatings on SKD11 tool steel nitrided prior to the coating layer formation for the strengthening of adhesive properties of coatings have been conducted. The thickness and hardness of the coatings increased with the increase of methane(CH₄) gas flow rate. However, wear properties of the coating were impaired by the increase of emthane(CH₄) gas flow rate. Maximum critical excoriation load of 54N for the Ti(C,N) coating was obtained with the methane(CH₄) flow rate were 2㎛ and 1650Hv(with the load of 50g) respectively. The concentration of carbon and nitrogen was graded from the outer surface of the coating to the coating/alloy interface. Concentration of carbon was higher at the outer surface of the coating and the nitrogen concentration was higher at the interface. The hardness and critical excoriation load of the Ti(C,N) coating was not dependant of the surface roughness and tempering temperature of SKD11 steel prior to the coating layer formation.

한랭작업 근로자들의 건강위해에 관한 연구

박호추,정설미,문덕환,이종태,김대환,김정호,최재일,황용식,이용희,이채언 大韓産業醫學會 1999 대한직업환경의학회지 Vol.11 No.1

In order to evaluate the status of cold exposure and its health hazards of workers at cold storage workplaces and to provide basic data for effective health care, the author measured core temperature and also observed clinical symptoms and signs, past and present history, and general health examination data on 99 cold exposed workers for exposure group and 96 non-exposed workers for control group working at 2 food refrigerating companies in Pusan area from January 6, 1998 to February 24, 1998. The results were as follows: 1. There was statistically significant difference in water intake between the exposure and control group and increased urine volume, urine frequency in exposure group without statistically significant difference. 2. Past and present illness in exposure group were hypertension (18.2%), hepatopathy (8.1%), gastro-intestinal disease(7.1%), arthritis (4.0%), intervertebral disc herniation(4.0%), and so on, and hypertension, arthritis was statistically significant difference compared to control group. 3. Symptoms in exposure group were fatigue(89.9%), headache (64.6%). drowsy(63.6%), neck stiffness(59.6%), excessive food intake(59.6%). general weakness(58.6%), hunger(58.6%), numbness(54.5%), and so on, and there was statistically significant difference between the exposure and control group except fatigue, drowsy. 4. As results of clinical test abnormality rate of the systolic, diastolic blood pressure and electrocardiogram were significantly higher in exposed group than control. 5. Core temperature in exposure group was statistically significantly lower than control group and the highest statistically significant inverse correlation with the working hours and working frequency of daily mean cold storage. As above results, the author suggested that the further studies should be conducted to evaluate the health status of workers about chronic health effects in cold workplaces and to establish effective health care methods for them.

梁建植 文學硏究

朴湧植,高宰錫 고려대학교 민족문화연구소 1991 民族文化硏究 Vol.24 No.-

연강우량 자료를 이용한 수문시계열의 특성 분석

유재성,강인식,박준일,신형우 慶尙大學校生産技術硏究所 1999 生産技術硏究所論文集 Vol.15 No.-

As the water resources planning is work out, it should have stationarity and randomness to be used hydrological time series data for frequency analysis or modeling which are kinds of probability analysis. But, in the case of domestic, we assume that the hydrological time series data is stationarity but, is not randomness, so it is usual to work out the hydrological analysis. Therefore, as a result, we can not be eliminate the possibility that the hydrological analysis brings about distorted results. Accordingly, in this research, to analysis the properties of hydrological time series data, the trend test, stationary and randomness test were used. The summary of results is as below. Result of the properties of hydrological time series data, in most of the points, the tendency is not indicated, the time series was revealed as randomness which does not have hydrological persistence as definitely stationary. But, from data of yearly rainfall, points for Taegwallyong, Ullungdo, both nonstationarity and persistence were indicated.

양방향 요소제거법을 이용한 신뢰성 기반 최적설계

유진식,박재용,황승민,임민규,오영규,한석영 한국공작기계학회 2008 한국공작기계학회 추계학술대회논문집 Vol.2008 No.-

This research presents a Reliability-Based Topology Optimization (RBTO) using Bi-directional Evolutionary Structural Optimization (BESO). An actual design involves uncertain conditions such as material property, operational load and dimensional variation. Deterministic Topology Optimization (DTO) is obtained without considering of uncertainties related to the uncertainty parameters. However, RBTO involves evaluation of probabilistic constraints, which can be done in two different ways, the reliability index approach (RIA) and the performance measure approach (PMA). The reliability index approach (RIA) and the performance measure approach (PMA) are adopted to evaluate the probabilistic constraints. In order to apply the BESO method to the RBTO, sensitivity number is defined as the change in the reliability index due to the addition or the removal of the ith element. In the BESO, a mesh-independency filter using nodal variables is used to remove the checkerboard patterns. The optimal topologies of RIA and PMA are obtained very similarly. It is shown that RBTO based on BESO can be effectively applied from the presented examples.

WMT를 이용한 인터넷 방송국 구축

김홍식,이영진,조재영,주영훈,박주연,송선아 인제대학교 기초과학연구소 2000 자연과학 Vol.4 No.-

WMT(Windosw Media Technologies)는 Microsoft에서 만든 인터넷 또는 인트라넷상에서 고품질의 오디오/비디오를 실시간으로 전송하여 주는 멀티미디어 스트리밍 기술이다. WMT는 대부분의 로컬 및 스트리밍 멀티미디어 파일 형식을 지원하기 때문에 개발자들은 어떤 웹 어플리케이션이나 사이트에라도 오디오와 비디오 방송을 구축할 수 있다. WMT에 포함된 Windows Media Encoder, Windows Media On Demand Producer등을 이용하고 전용서버를 설치하여 on-Demand방송이나 실시간 인터넷 방송을 구축할 수 있다. WMT is the multimedia streaming technology which transfer the audio and video on Internet or Intranet. Because WMT supports almost styles of local and streaming multimedia file, some developers build the radio and video broadcasting system at any web applications and sites. This paper shows the method of develop the realtime internet broadcastion system with WMT.

L-Moment 법을 이용한 지점가뭄빈도 해석

유재성,강인식,박준일,신형우 慶尙大學校生産技術硏究所 1999 生産技術硏究所論文集 Vol.15 No.-

In this research, the drought analysis was derived with monthly rainfall data from 59 stations from the Korea meteorological Administration. the point frequency analysis was derived with L-moment's method and indicated the fitted probability distribution for 59 points. also estimating the probability drought rainfall of the duration(4, 6, 8, 10, 12 months) and return period(2, 5, 10, 20, 50, 100 years). Thus, indicated probability drought rainfall frequency figure for whole area of country.

Van der Woude 증후군 1예

최홍식,임재열,박준호,남지인 대한이비인후과학회 2001 대한이비인후과학회지 두경부외과학 Vol.44 No.11

국내 혈액질환 환자에서 침습성 아스페르길루스증의 구제치료로서 Voriconazole의 효과와 안전성

권재철,김시현,최수미,최재기,이동건,박선희,최정현,유진홍,신완식 대한감염학회 2010 감염과 화학요법 Vol.42 No.1

Background: Invasive aspergillosis (IA) is associated with significant morbidity and mortality in patients with hematologic malignancies. We investigated the efficacy and safety of voriconazole (VCZ) when used as salvage therapy for IA in Korean adults with hematologic malignancies who had not responded to prior antifungal therapy. Materials and Methods: We retrospectively reviewed data, collected from January 2007 to October 2008, from patients with proven or probable cases of IA. All were probable IA cases, except for one proven case. All cases were refractory or intolerant to antifungal therapy prior to administration of VCZ. Efficacy and safety were assessed in patients treated with VCZ for more than 3 days and for more than one dose, respectively. A favorable response [complete (CR) or partial (PR)] was defined by significant improvement of all clinical symptoms, signs, and radiologic abnormalities. Results: Fifty patients who met the inclusion criteria were enrolled. There were 27 male and 23 female patients with mean age of 44.4 years (range, 15-65 years). Underlying diseases were acute leukemia (35 cases), chronic myelogenous leukemia (4 cases), myelodysplastic syndrome (3 cases), lymphoma (3 cases) and other hematologic diseases (5 cases). Twenty-two patients had received chemotherapy and 13 patients had undergone hematopoietic stem cell transplantation. The lung was the main infection site (94%) followed by the sinus (6%). Amphotericin B deoxycholate alone was the most frequent previous antifungal therapy. The mean duration of antifungal therapy prior to VCZ therapy was 13.9±8.8 days (2-44 days). The median duration of VCZ therapy was 19 days (interquartile range, 49 days). Sixteen patients (32.0%) showed favorable responses (CR:PR=8:8) at the end of VCZ therapy. The numbers of patients with stable disease, progression and death were, 6 (12%), 6 (12%) and 22 (44%) respectively. Most of those with unfavorable responses had relapsed underlying malignancies or refractory graft versus host diseases. Twelve patients developed drug-related adverse events but only one patient stopped VCZ treatment prematurely. Conclusions: VCZ demonstrated an acceptable level of toxicity in patients with hematologic malignancies but further studies are required to prove its efficacy as salvage therapy.