수소산업에의 공정시스템 기술 적용

원왕연 한국공업화학회 2021 한국공업화학회 연구논문 초록집 Vol.2021 No.1

CO₂회수용 PSA 공정의 적응 격자 배열 기반 비선형 관측자 시스템

원왕연,이광순 제어로봇시스템학회 2012 제어로봇시스템학회 국내학술대회 논문집 Vol.2012 No.4

Production of Bioplastics: Process Synthesis and Evaluation

원왕연 한국공업화학회 2020 한국공업화학회 연구논문 초록집 Vol.2020 No.-

2,5-Furandicarboxylic acid (FDCA) has attracted considerable attention as a building block for renewable polymers, as it can substitute conventional petroleum-derived terephthalic acid as a monomer for the synthesis of polyethylene terephthalate. In this study, we develop a new process for the co-production of FDCA, furfural, and activated carbon from lignocellulosic biomass to make the production of renewable plastics cost-competitive by generating high-value chemicals at the same time. Pinch analysis was conducted to form a heat exchanger network for reducing utility requirements. We conducted an uncertainty analysis using the Monte-Carlo simulation method for the minimum selling price of FDCA to quantify the risks of the proposed process and provide a more realistic estimation to decision makers. Furthermore, the sustainability of the proposed process was demonstrated via life-cycle assessment.

Changes of Plasma Adiponectin Levels after Smoking Cessation

원왕연,김대진,이창욱,채정호,김정진,이철 대한신경정신의학회 2014 PSYCHIATRY INVESTIGATION Vol.11 No.2

Objective Cigarette smoking is associated with a variety of health problems including cardiovascular, pulmonary, neoplasms, endocrinopathies including diabetes, the metabolic syndrome, and chronic inflammation. Adiponectin is an adipocyte-derived plasma protein that is closely associated with insulin sensitivity and the metabolic syndrome. The aim of this study was to evaluate the changes of plasma adiponectin levels after smoking cessation. Methods Thirty seven smokers that wanted to stop smoking without any nicotine replacement therapy or medication were recruited for this study. Fifteen smokers succeeded in stopping smoking (validated by urine cotinine levels ≤50 ng/mL) and 22 smokers failed. Therefore, only the 15 that succeeded were included in the analysis. The plasma adiponectin levels were determined using a commercially available enzyme-linked immunosorbent assay. Results The mean age of the successful 15 was 35±9.3 years old. They were all males. The daily smoking habit was a mean of 13.5±5.4 cigarettes per day. The mean Nicotine Dependence Syndrome Scale (NDSS) and Fagerstrom Test for Nicotine Dependence (FTND) scores were 55.6±9.6 and 2.9±1.9. During the study period of three months, the mean body mass index (BMI), body fat mass (BFM), waist-hip ratio (WHR) and body weight increased by 1.1 kg/m2, 3.0%, 0.02%, and 2.9 kg, respectively. The baseline mean adiponectin level in the subjects was 11.9±5.2 mg/L. The mean adiponectin levels measured at one and three months were 16.0±5.1 mg/L and 14.7±4.5 mg/L respectively. The mean plasma adiponectin levels of the successful group was significantly increased after four weeks when compared to the baseline (z=-2.401, p=0.016). However, the decrease in plasma adiponectin levels at one and three months was not statistically significant. Conclusion Even though the decrease over the next two months was not significant, these findings, the increase of plasma level of adiponectin after smoking cessation, provide preliminary data for future research on the possible mechanisms associated with smoking cessation and changes in body metabolism.

Combined run-to-run and LQG control of a 12-inch RTP equipment

원왕연,Sang Hyun Ji,Byung-Cheol Na,Woohyun Yun,이광순 한국화학공학회 2009 Korean Journal of Chemical Engineering Vol.26 No.6

A combined run-to-run (R2R) and LQG control method has been proposed for rapid thermal processing (RTP) equipment for run-wise improvement and real-time multivariable control of the temperature uniformity over the wafer surface. The standard LQG objective was modified to include a quadratic penalty term for input deviation from bias values which are updated by an R2R control law. The proposed method has been applied to commercial 12- inch rotating RTP equipment with four pyrometers and ten circular groups of tungsten-halogen lamps for measurements and manipulation of wafer temperatures. The performance of LQG control was evaluated under wafer rotation and found to show quite accurate tracking. For evaluation of the combined control technique, a wafer with seven thermocouples (TC’s) attached along the radial direction has been employed for the TC measurements to be used for R2R control, whereas the pyrometer measurements are fed back for real-time LQG control. It was observed that the temperature uniformity is improved as the run number increases.

CO2 회수를 위한 2단계 PSA 공정의 경제성 평가

원왕연,이광순 제어로봇시스템학회 2010 제어로봇시스템학회 국내학술대회 논문집 Vol.2010 No.5

Process Synthesis and Technoeconomic Analysis

원왕연 한국공업화학회 2019 한국공업화학회 연구논문 초록집 Vol.2019 No.1

We propose an integrated strategy for the production of 2,5-furandicarboxylic acid (FDCA) from fructose. In this process, fructose is first dehydrated to hydroxymethylfurfural (HMF) at high yield (70%) using a gamma-valerolactone (GVL)/H₂O solvent system. HMF is then oxidized to FDCA over a Pt/C catalyst with 93% yield. The advantage of our system is the higher solubility of FDCA in GVL/H₂O, which allows oxidation at high concentrations using a heterogeneous catalyst that eliminates the need for a homogeneous base. Our process eliminates the use of corrosive acids, because FDCA is an effective catalyst for fructose dehydration, leading to improved economic and environmental impact of the process. Our technoeconomic model indicates that the overall process is economic and environmental impact of the process. Our technoeconomic model indicates that the overall process is economically competitive with current terephthalic acid processes.

Self-optimizing control of a natural gas liquefaction process

원왕연 한국공업화학회 2021 한국공업화학회 연구논문 초록집 Vol.2021 No.0

Parameter Estimation and Dynamic Control Analysis of Central Carbon Metabolism in Escherichia coli

원왕연,Changhun Park,Changhun Park,이상엽,이광순,이진원 한국생물공학회 2011 Biotechnology and Bioprocess Engineering Vol.16 No.2

The central carbon metabolic pathway is the most important among metabolic pathways in all microorganisms since it produces energy and precursors for biosynthesis. In this study, a dynamic model for central carbon metabolism in Escherichia coli (E. coli) consisting of the phosphotransferase (PTS) system, glycolysis,pentose-phosphate pathway (PPP), and storage materials was obtained by ameliorating the model proposed by Chassagnole et al. (2002). In order to improve the performance of the model, principal parameters were estimated through the experimental measurements of intracellular concentrations of metabolites under transient conditions. Through dynamic metabolic control analysis (MCA), the tendencies of the metabolic fluxes at branch points were investigated, and the key parameters and enzyme kinetics that most dominantly affected the productivity of the desired metabolites were determined.

노인 정신질환 약물치료

원왕연,이창욱 대한의사협회 2010 대한의사협회지 Vol.53 No.11

Psychiatric disturbances in the elderly are complicated. Dementia and depression are serious causes of global impairment in the elderly. Aging is characterized by a progressive functional impairment of multiple organs, a reduction of homeostatic mechanisms, and a changed sensitivity or capacity of neurotransmitter receptors. Understanding the influence of age-dependent changes in the composition and function of the body on the pharmacokinetics and pharmacodynamics of drugs is important before prescribing drugs to elderly patients. However, there is little clinical pharmacological information available to guide pharmacotherapy for late-life psychiatric disorders. Treatment of dementia is based on the cognitive decline and behavioral symptoms that accompany dementia. Currently prescribed antidepressants have similar efficacies but the side effect profiles vary. Comprehension of the normal aging process and understanding the characteristics of each of the psychotropics are essential in geriatric psychopharmacology. Up to the present, most studies are confirmations or reproductions of previous results on efficacy or safety. Future directions for psychopharmacological research should include discovering newer drugs,treatment of resistance or nonresponders, and combination or adjunctive therapies. This review focused on the geriatric pharmacokinetic/pharmacodynamic changes and clinical information regarding currently prescribed psychotropic medications.