• Bulletin of the Korean Chemical Society
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• v.34 no.11
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• pp.3284-3288
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• 2013

This paper describes first development and validation of pentafluorophenylprophyl ligand-based liquid chromatography coupled to tandem mass spectrometry (PFPLC-MS/MS) method to determine metformin, a highly polar compound, in human plasma. Metformin and Phenformin (internal standard) were extracted from human plasma 50 ${\mu}L$ with a single-step protein precipitation. The chromatographic separation was performed using a linear gradient elution of mobile phase involving 5.0 mM ammonium formate solution with 0.1% formic acid (A) and acetonitrile (B) over 3.0 min of run time on a Phenomenex Luna PFP column. The detection was performed using a triple-quadrupole tandem mass spectrometer (Waters Quattro micro) with electrospray ionization in the mode of positive ionization and multiple-reaction monitoring (MRM). The developed method was validated with 5.0 ng/mL of lower limit of quantification (LLOQ). The calibration curve was linear over 5-3000 ng/mL of the concentration range ($R^2$ > 0.99). The specificity, selectivity, carry-over effect, precision, accuracy and stability of the method met the acceptance criteria. The method developed in this study had had rapidness, simplicity and ruggedness. The reliable method was successfully applied to high throughput analysis of real samples for a practical purpose of a pharmacokinetic study.

• Nutrition Research and Practice
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• v.12 no.5
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• pp.371-377
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• 2018

BACKGROUND/OBJECTIVES: Elevation of postprandial lipemia characterized by a rise in triglyceride (TG)-rich lipoproteins can increase the risk of atherogenesis. The objective of this study was to investigate postprandial lipemia response to a single dietary fat/sugar load test and monitor beneficial changes induced by the consumption of Platycodi radix (AP) beverage in healthy subjects. SUBJECTS/METHODS: A total of 52 subjects were randomly assigned to either placebo or AP beverage group with a high-fat shake in a randomized controlled crossover trial. Postprandial blood was collected at 0, 1, 2, 4, and 6 h and analyzed for TG and lipoprotein lipase mass. Inhibition of pancreatic lipase was determined in vitro. RESULTS: AP inhibited pancreatic lipase activity in vitro ($IC_{50}=5mg/mL$). Compared to placebo beverage, AP beverage consumption with a high-fat shake induced significant increase of plasma lipoprotein lipase mass (P = 0.0111, ${\beta}$ estimate = 4.2948) with significant reduction in very low-density lipoprotein (VLDL) TG concentration (P = 0.038, ${\beta}$ estimate = -52.69) at 6 h. Based on significant correlation between high-fat dietary scores MEDFICTS and postprandial TG responses in VLDL (P = 0.0395, r = 0.2127), subgroup analysis revealed that 6 h-postprandial VLDL TG response was significantly decreased by AP consumption in subjects with MEDFICTS ${\geq}40$ (P = 0.0291, ${\beta}$ estimate = -7214). CONCLUSIONS: AP beverage might have potential to alleviate postprandial lipemia through inhibiting pancreatic lipase activity and elevating lipoprotein lipase mass. Subgroup analysis revealed that subjects with high-fat dietary pattern could be classified as responders to AP beverage among all subjects.

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.4
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• pp.538-548
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• 2000

A study analyzes the eclectic trend shown in Andy Warhol look to explain the pluralistic aspect which is expressed in the late 20th century's fashion. Eclecticism is a trial to dismantle the barriers between pure art and popular art, high culture and low culture. This pursues harmonious accommodation and coexistence of all areas without being confined in the conventional lofty taste or high art. This thesis studies the characteristic aspects of the eclectic trend by classifying this trend into sell culture, mass media and fashion around the Andy Warhol look. The sexual eclectic trend in Warhol look is bisexual one shown in clubland and the world of modeling and supplies fashion with abundant expression and ambiguity. Warhol established cultural eclecticism by compounding high cultural factors and low cultural factors. broke up the boundary between street fashion and high fashion and escaped from the fixed idea on materials and design. Also he generalized and democratized specialty or nobility conventional paintings had possessed through introducing repetition and mediocrity and fully utilized every kind of mass media, Hollywood movie stars and daily necessaries in producing works. Andy Warhol who asserted‘Business Art’that was the mixed form of artistry and commercialism had creative and futuristic taste and proposed the direction to develop current fashion and art where the concept of economy is importantly brought into relief.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.1
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• pp.61-68
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• 1991

The system such as railway bridge can be modelled as the restrained beam with intermediate supports. This kind of structures are subject to the moving load, which has a great effect on dynamic stresses and can cause sever motions, especially at high velocities. Therefore, to analyze the dynamic characteristics of the system due to the moving load is very important. In this paper, the governing equation of motion of a restrained beam subjected to the moving load is derived by using the Hamilton's principle. The orthogonal polynomial functions, which are trial functions and satisfying the geometric and dynamic boundary conditions, are obtained through simple procedure. The dynamic response of the system subjected to the moving loads is obtained by using the Galerkin's method and the numerical time integration technique. The numerical tests for various constraint, velocity and boundary conditions were preformed. Furthermore, the effects of mass of the moving load are studied in detail.

• Korean Journal of Health Education and Promotion
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• v.20 no.3
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• pp.1-18
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• 2003

This study was conducted to evaluate factors related to the recogniton and behavioral intention for smoking cessation programs. Five effective smoking cessation programs were considered： acupuncture, nicotine patch, clinic program, mass education, and alliance programs. To explain the health behavior for smoking and smoking cessation programs, a five-stage behavioral intention model was built, and 500 questionnaires were completed through a telephone survey. Stages of the model included recogniton of the programs, past experiences, present smoking status, intention for smoking, and behavioral intention for smoking cessation programs. The results showed that the recogniton rate of the programs were low in general, therefore strategies of education, public relations, and advertisement need to be pursued. Nicotine dependency resulted in the fact that success rates were low although trial rates of smoking cessation were high among smokers. The necessity for smoking cessation programs was suggested. And the significant factors related to the intention for smoking cessation were individual attitude and reluctancy to pay time and money. Others' attitude was insignificant to subjects' smoking cessation. Purchase rates for nicotine patches were 11.3％ for male and 27.3％ for female, those for acupunture were 7.6％ for male and 10.0％ for female. There were very low purchase rates for clinic, mass education, and alliance programs. In conclusion, evidence-based and effective smoking cessation programs need to be promoted by medical doctors. Strategies in education, public relations, and advertisement also need development. In addition, continuing legal and systematic support for smoking cessation would lower the smoking rate and ultimately contribute to the nation's health.

• Journal of Advanced Marine Engineering and Technology
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• v.31 no.6
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• pp.768-776
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• 2007

In this study, axial vibration analysis has been conducted on a propulsion and lift shafting system for an air cushion vehicle using ANSYS code. The shafting system is totally flexible multi-elements system including wood composite material of air propeller. aluminum alloy of lift fan and thin walled shaft with flexible coupling. The analysis calculated the axial natural frequencies and mode shapes of the shafting system taking into account an equivalent mass-elastic model for shafting system as well as the three-dimensional models for propeller blade and fan impeller. Such a flexible shafting system has very intricate vibrating characteristics and especially, axial natural frequencies of flexible components such as propeller blade and impeller of lift fan can be lower to the extent that causes a resonance in the range of operating revolution. The results for axial vibration analysis are presented and compared with the results of axial vibration test for lift fan conducted during Sea Trial.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.892-896
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• 2001

Investigation is performed on the stability of nonlinear system under turbulent fluid motion modelled as white noise random process, which is a preliminary result in the course of research on the characteristic and nonlinear control of the stochastic system. Adopted physical model is beam-type structure with tip-mass and main base mass. The governing equation is derived via F-P-K approach in stochastic sense. By means of Gaussian Closure method infinite dynamic moment equations due to system nonlinearity is closed to finite one. At the best of authors' knowledge, it is the first trial to design nonlinear controller by using of sliding mode technique in stochastic domain and control performance and effect in stochastic domain is studied.

• Korean Institute of Interior Design Journal
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• no.6
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• pp.53-62
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• 1995

This research aims at proving the fact that the forms, spaces and many other design concepts of Modernism are much related with the changes of materials, struc-tures, and the way of construction as well as the idealis-tic and aesthestic things through the history of steel, one of the most important materials of the style. The meaning steel has in the modern architecture can be studied in the structure and industrial production system. 1) Steel frame broadened the range of understanding the space and created the new form through the skeleton/skin structure by reinterpreting the existing space fac-tors while it was being adopted to the architecture. Walls could be freed from the traditional function of bear-ing wall and roofs gave the transparancy to the interior by being linked with the glass. Posts lost the function which confines the space in the frame of the grid system and gave the flexibility to the interior due to the economical materials. These changes made the movable partition, screen with various materials and the system furniture which divides the space more important. 2) In the aspect of the industrialized architecture, it be-came the moment that the most of the archtectural com-posing parts were in mass production as they were standarized, high qualified, and generalized by the indus-trial characteristics of steel, and the specialization of structure and cladding, but the neither of the efforts to make the building itself by mass production or to standarize it was fulfilled. The high-tech architecture which borrows its archtectural manifestation from the high technology, however, is consistently paying efforts on such industrialization.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.2
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• pp.121-128
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• 2011

As high precision industries such as semiconductor, TFT-LCD manufacturing and MEMS continue to grow, the demand for higher DOF precision stages has been increasing. In general, the stages should accommodate a prescribed range of payloads in order to position various precision manufacturing/inspection instruments. Therefore a nonlinear controller using sliding motion is developed, which bears mass perturbation and makes the upper plate of the stage move in 6 DOF. For the application of the nonlinear control, an observer is also developed based on expected noise covariance. To eliminate the steady state error of step response, integral terms are inserted into the state-space model. The linear term of the controller is designed using optimization scheme in which parameters can be weighted according to their physical significance, whereas the nonlinear term of the controller is designed using trial and error method. A comprehensive simulation study proves that the designed controller is robust against mass perturbation and completely eliminates steady state errors.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.1
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• pp.113-119
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• 2012

The aim of this study was to investigate the differences in blood homocysteine levels and blood d-dimer levels of cerebral infarction patients categorized by Pattern Identification. We studied hospitalized patients within 4 weeks after the onset of stroke who were admitted to the Oriental Internal Medical Department at Semyung University Chungju Oriental Medical Hospital from May 2008 to September 2009. We analyzed risk factors and blood homocysteine levels and blood d-dimer levels accordings to Pattern Identification in Cerebral infarction patients. A total of 49 patients were included in the trial. No statistical significance was noted for any characteristics except body weight and body mass index. Body weight and body mass index were significantly higher Dampness-Phlegm pattern. On past history of patients, prevalence of DM was significantly higher in Fire-Heat pattern than that of other patterns. There was no significant difference of blood homocysteine levels and blood d-dimer levels among Pattern Identification. This study investigated the differences in blood homocysteine levels and blood d-dimer levels of cerebral infarction patients categorized by Pattern Identification. The correlation in homocysteine and d-dimer levels and Pattern Identification was not clarified.