• Journal of Nutrition and Health
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• v.27 no.8
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• pp.819-827
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• 1994

The present study was undertaken to evaluate the effects of 50% buckwheat diet on the body weight, organ weight, urine albumin, urine glucose, plasma glucose and plasma lipid in normal rats and diabetic rats treated with streptozotocin(STZ). The food intake, body weight, the level of urine glucose in diabetic buckwheat groups were not significantly different with diabetic control group. The level of urine albumin was lower in raw and steam buckwheat group than in the diabetic control group. Compared to the normal control group, liver and kidney weights were heavier in the diabetic groups. Pancreas weight was heavier diabetic buckwheat groups than in normal and diabetic control groups. Fasting plasma glucose level of diabetic buckwheat groups significantly decreased by 18-37% compared with the diabetic control group. Plasma triglyceride level of diabetic buckwheat groups significantly decreased by 34-50% compared with the diabetic control group. Plasma total cholesterol level of diabetic buckwheat groups decreased by 15-27% compared with the diabetic control group. The level of HDL-cholesterol was not affected by buckwheat diet. These results indicate that buckwheat is an effective therapeutic regimen for the control of metabolic derangements in diabetics.

• Nuclear Engineering and Technology
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• v.56 no.1
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• pp.216-221
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• 2024

Ion cyclotron range of frequency (ICRF) heating system is an important auxiliary heating method in the experimental Advanced Superconducting Tokamak (EAST). In EAST, several megawatts of power are transmitted with coaxial transmission lines and coupled to the plasma. For the long pulse and high power operation of the ICRF waves heating system, it is very important to effectively control the power and initial phase of the ICRF signals. In this paper, a power and phase feedback control system is described based on field programmable gate array (FPGA) devices, which can realize complicated algorithms with the advantages of fast running and high reliability. The transmitted power and antenna phase are measured by a power and phase detector and digitized. The power and phase feedback control algorithms is designed to achieve the target power and antenna phase. The power feedback control system was tested on a dummy load and during plasma experiments. Test results confirm that the feedback control system can precisely control ICRF power and antenna phase and is robust during plasma variations.

• Nuclear Engineering and Technology
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• v.55 no.2
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• pp.595-602
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• 2023

The EAST ICRF system operating space has been extended in power and phase control with a low-level RF system for the new double-strap antenna. Then the multi-step power and periodic phase scanning experiment were conducted in L-mode plasma, respectively. In the power scanning experiment, the stored energy, radiation power, plasma impedance and the antenna's temperature all have positive responses during the short ramp-ups of P_L;ICRF. The core ion temperature increased from 1 keV to 1.5 keV and the core heating area expanded from |Z| ≤ 5 cm to |Z| ≤ 10 cm during the injection of ICRF waves. In the phasing scanning experiment, in addition to the same conclusions as the previous relatively phasing scanning experiment, the superposition effect of the fluctuation of stored energy, radiation power and neutron yield caused by phasing change with dual antenna, resulting in the amplitude and phase shift, was also observed. The active control of RF output facilitates the precise control of plasma profiles and greatly benefits future experimental exploration.

• Journal of Institute of Control, Robotics and Systems
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• v.4 no.4
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• pp.433-440
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• 1998

The purpose of this study is to provide an integrated process control system for plasma etching. The control system is designed to employ neural network for the modeling of plasma etching process and to utilize genetic algorithm to search for the appropriate selection of control input variables, and to provide a control chart to maintain the process output within a desired range in the real plasma etching process. The target equipment is the one operating in DRAM production lines. The result shows that the integrated system developed is practical value in the improved performance of plasma etching process.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.1
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• pp.39-45
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• 1996

The study was performed to investigate the effects of administration of aluminum compound in Kidney metabolism and plasma hormone of rats. Seventy frve male Sprague-Dawley strains rats were divided into five groups consisting of the control, 250ppm AlCl$_3$group, 500ppm AlCl$_3$ group, 250ppm $Al_2$(SO$_4$)$_3$group, 500ppm $Al_2$(SO$_4$)$_3$group and kept on the diet for 2 weeks. The body weight gain was increased by the administration of AlCl$_3$ but decreased by the administration of $Al_2$(SO$_4$)$_3$as compared to the control. The urinary excretion of sodium and creatinine were increased and free water clearance and urine volume were decreased significantly after AlCl$_3$adminstration group as compared to the control. The water balance, free water clearance, excretion of sodium and creatinine were increased and the excretion of chlorine was decreased after $Al_2$(SO$_4$)$_3$ administration as compared to the control. Plasma renin activity was increased and plasma aldosterone content was compared to the control. Plasma renin activity was increased and plasma aldosterone content was significantly decreased after adminstration of aluminum compounds as compared to the control.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.7
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• pp.132-140
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• 2000

Plasma arc cutting is one of the most widely used processes in metal cutting fields and is a process that produces parted metal plates by cutting them with an arc plasma established between the electrode tip and the plate(workpiece). When the tip-to-workpiece distance varies during cutting, the cut quality, for example the kerf width, is deteriorated by the change of plasma arc. The variations of tip-to-workpiece distance are due to the different factors such as inaccuracies in setting the torch or workpiece, thermal distortions during cutting, and uneven surface of workpiece. The control to keep the tip-to-workpiece distance constant is thus indispensable to improve the flexibility of automatic plasma arc cutting system applications. In this study, an arc sensor which utilizes the electrical signal obtained from the plasma arc itself was developed. The arc sensor has an advantage that no particular sensing device is necessary and real-time sensing of the tip-to-workpiece distance is possible directly under the plasma arc. The relationship between plasma arc voltage and tip-to-workpiece distance was determined through the repeated experimental results. The model was used for developing an automatic tip-to-workpiece distance control system of plasma arc cutting. It could be shown that the proposed system has a successful capability of tip-to-workpiece distance control.

• Nuclear Engineering and Technology
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• v.25 no.1
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• pp.136-147
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• 1993

The paper describes : ⅰ) Mathematical modeling of poloidal flux to define and calculate the tokamak plasma position based on a property of the plasma boundary which is always a flux surface. Controlling the plasma boundary position is therefore equivalent to equalizing the flux value on several points belonging to a curve tangent to the limiter. ⅱ) Experimental method for determining the outmost poloidal isoflux surface by a linear combination of measurements of magnetic fluxes, fields and field gradients, without requiring knowledge of internal plasma parameters for the feedback control, i.e., with neither corrections for variation in the poloidal beta and the plasma current distribution, nor compensations for the induced currents in the vacuum vessel. ⅲ) Feedback control algorithm for the regulation of plasma boundary position and its electronics hardware based on the PID control theory. ⅳ) Experimental results obtained from the RTP tokamak experiments using the present plasma control system.

• Journal of Nutrition and Health
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• v.32 no.3
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• pp.221-229
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• 1999

Certain indigestible oligosaccharides may benefit gastrointestinal tract via fermentation and proliferation of desirable bacterial species. The purose of this study was to elucidate the effect of selected oligosaccharides, such as fructooligosaccharides(FOS), soybean oliosaccharides(SOE), and highly concentrated branched oligosaccharides(HiBOS), on fecal micorflora proliferation, lipid concentration, lipid peroxide formation and antioxidant enzymes acitivies in plasma and liver of the rats. Thirty two male Sprague-Dawley rats were randomly assigned to one of four treatments ; 1) control diet(AIN-93G diet); 2) control diet +5% FOS ; 3) control diet + 5% SOE ; 4) control diet + 5% HiBOS. The duration of the study was 4 weeks. Fecal bifidobacteria concentration were significantly higher (p<0.05) in the HiBOS group compared with the control after 4 weeks of dietary treatment. FOS and SOE groups also had higher fecal bifidobacteria levels than control, but statistical significance was not found. The concentration of plasma total lipid was decreased by oligosaccharide consumption, especially in HiBOS group(p<0.05). The concentration of plasma total triglyceride was significantly lower in all of the oligosaccharide containing groups compared with the control(p<0.05). The plasma total cholesterol concentration tended to be lower in the oligosaccharide consuming groups than control. The concentrations of hepatic total lipid, triglyceride and total cholesterol were not affected by consumption of oligosaccharides. Thiobarbituric acid reactive substance(TBARS) concentrations and antioxidant enzyme activities in plasma and liver were not affected much by experimental diets. There results suggest that dietary oligosaccharides may be beneficial for increasing intestinal bifidobacteria and lowering plasma lipid levels.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.77-77
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• 2016

Thin films synthesized by plasma processes have been widely applied in a variety of industrial sectors. The structure control of thin film is one of prime factor in most of these applications. It is well known that the structure of this film is closely associated with plasma parameters and species of plasma which are electrons, ions, radical and neutrals in plasma processes. However the precise control of structure by plasma process is still limited due to inherent complexity, reproducibility and control problems in practical implementation of plasma processing. Therefore the study on the fundamental physical properties that govern the plasmas becomes more crucial for molecular scale control of film structure and corresponding properties for new generation nano scale film materials development and application. The thin films are formed through nucleation and growth stages during thin film depostion. Such stages involve adsorption, surface diffusion, chemical binding and other atomic processes at surfaces. This requires identification, determination and quantification of the surface activity of the species in the plasma. Specifically, the ions and neutrals have kinetic energies ranging from ~ thermal up to tens of eV, which are generated by electron impact of the polyatomic precursor, gas phase reaction, and interactions with the substrate and reactor walls. The present work highlights these aspects for the controlled and low-temperature plasma enhanced chemical vapour disposition (PECVD) of Si-based films like crystalline Si (c-Si), Si-quantum dot, and sputtered crystalline C by the design and control of radicals, plasmas and the deposition energy. Additionally, there is growing demand on the low-temperature deposition process with low hydrogen content by PECVD. The deposition temperature can be reduced significantly by utilizing alternative plasma concepts to lower the reaction activation energy. Evolution in this area continues and has recently produced solutions by increasing the plasma excitation frequency from radio frequency to ultra high frequency (UHF) and in the range of microwave. In this sense, the necessity of dedicated experimental studies, diagnostics and computer modelling of process plasmas to quantify the effect of the unique chemistry and structure of the growing film by radical and plasma control is realized. Different low-temperature PECVD processes using RF, UHF, and RF/UHF hybrid plasmas along with magnetron sputtering plasmas are investigated using numerous diagnostics and film analysis tools. The broad outlook of this work also outlines some of the 'Grand Scientific Challenges' to which significant contributions from plasma nanoscience-related research can be foreseen.

• Clinical and Experimental Reproductive Medicine
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• v.14 no.2
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• pp.85-92
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• 1987

To estimate the influence of plasma copper and zinc concentration on infertility, we measured copper and zinc levels in plasma of 117 infertile women and 14 infertile men by atomic absorption spectrophotometry from January, 1987 through June, 1987 and the results were as follows. 1. The mean plasma copper level was significantly lower in infertile women than in fertile control women while mean plasma zinc level significantly higher in infertile women than in fertile control women. 2. A significant difference in the mean plasma level between infertile women with tubal and endometrial factor and normal controls was noted. 3. The mean level of copper in plasma of azoospermic patients was significantly higher than in fertile control subjects. 4. In fertile control and infertile women, no diurnal and menstrual cyclic variations in plasma zinc and copper levels were present, respectively. Also, there were no significant correlation between plasma zinc and copper levels in all studied group of subjects.