• Food Science and Biotechnology
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• v.14 no.3
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• pp.305-310
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• 2005

Flaxseed is outstanding for lignans and oil rich in ${\alpha}$-linolenic acid which protect against several major illnesses. Better understanding of processing and storage characteristics of flaxseed will increase options for food use. Lignans and oil are found in the hull and embryo, respectively. Comparison of pearling and impact-dehulling processes for separation of lignan and oil-rich fractions showed the impact process was less effective, but easier to scale-up. Screw-pressing embryo reduced oil yield compared to whole seed, but doubled productivity and sharply reduced frictional heating of the oil. Flaxseed hull and embryo, also whole, ground and steamed-ground samples, were stable up to 30 weeks in closed containers at $23^{\circ}C$. Steamed-ground samples in open trays at $40^{\circ}C$ deteriorated markedly (peroxide value > 100 by 22 weeks); yet, whole seed remained stable. Incorporation of 18% flaxseed embryo into yellow perch feed increased ${\alpha}$-linolenic acid to 13 to l4% of muscle and liver lipids, compared to 0.5 to 0.7% in the no-embryo control. Feed conversion ratio, weight gain, and survival were similar. These studies are helping to establish the technological base for processing and utilizing flaxseed and flaxseed fractions to improve human diets.

• Resources Recycling
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• v.22 no.4
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• pp.46-54
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• 2013

The produced quantity of waste plastics including waste vinyls was assumed as about 5 million tons per year. The quantity of waste vinyls produced from the waste recycling center among total quantity of waste plastics was estimated as about 1 million tons per year. Most of waste vinyls produced from the waste recycling center were recycled as refuse plastic fuel(RPF) or recycled feedstock material. In this study, the medium material using waste vinyls was made by the melting process of heat medium heating and the tensile strength was analyzed for checking the usable possibility of recycled waste vinyl material by comparing with the existent product. In order to use the medium material for producing the recycled product, it can be considered that the tensile strength of medium material is more than 100 $kgf/cm^2$.

• Resources Recycling
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• v.25 no.6
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• pp.3-12
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• 2016

In this study, Au distribution in F-PGA chip and W-BGA chip were examined to recover Au effectively from CPU chips. The result showed that 80.8% and 89.8% of Au exist in terminal of F-PGA chip and bare die of W-BGA chip, respectively. Based on the fact that Au exists in specific parts of the chips, an CPU chip dismantling apparatus was developed. The experimental variables were roller rotating speed, heat temperature of IR heater and heating time. Terminals of F-PGA chips were completely recovered under the temperature of $300^{\circ}C$ and the residence time of 90 s. Bare dies of W-BGA chips were completely recovered as well under the temperature of $300^{\circ}C$, the roller rotating rate of 90 rpm and the residence time of 90 s.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.8
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• pp.1478-1485
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• 2007

In this paper, a meteorological system including a wind speed & direction module and the DSP(Digital Signal Processor) sensor interface circuit board are proposed. This DSP system accepts and process the informations from a wind speed & direction module, the atmospheric pressure sensor, the ambient air temperature sensor and transfers it to the PC monitoring system. Especially, a wind speed & direction module and a DSP hardware are directly designed and applied. A wind speed & direction module have a construction that it have four film type RID(Resistive Temperature Detectors) resistive sensor adhered around the circular metal body heated constantly by heating coil for obtaining vector informations about wind. By this structure, the module is enabled precise measurement having a robustness about vibration, humidity, corrosion. A sensor signal processing circuit is using TMS320F2812 TI(Texas Instrument) Corporation high speed DSP. An economical meteorological system could be constructed through the data from wind speed & direction module and by the fast processing of DSP interface circuit board.

• Korean Journal of Metals and Materials
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• v.48 no.11
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• pp.974-980
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• 2010

Various types of steel, namely, 0.35C, 0.2C-Cr, and 0.2C-Cr-Mo steels, were quenched and tempered by high-frequency induction heat treatment. The type, size, and spheroidization of the carbides varied depending on the tempering temperatures ($450{\sim}720^{\circ}C$). During the tempering process, the carbide was precipitated in the martensite matrix. The 0.35C, 0.2C-Cr, and 0.2C-Cr-Mo steels contained carbides that were smaller than 120 nm. The carbide was spheroidized as the tempering temperature increased. Owing to the fine microstructure and spheroidization of the carbides, all three steels had a high tensile strength as well as yield ratio and reduction of area. In the case of the 0.2C-Cr steel, the use of Cr as an alloying element facilitated the precipitation of alloyed carbides with an extremely small particle and resulted in an increase in the spheroidization rate of the carbides. As a result, a large reduction of area was achieved (>70%). The 0.2C-Cr-Mo steel had the highest tensile strength because of the high hardenability that can be attributed to the presence of alloying elements (Cr and Mo). Quenching and tempering steels by induction heat treatment resulted in a high strength of over 1 GPa and a large reduction of area (>70%) because of the rapid heating and cooling rates.

• Journal of Ginseng Research
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• v.37 no.4
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• pp.475-482
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• 2013

The main active components of Panax ginseng are ginsenosides. Ginsenoside Rb1 and Rg1 are accepted as marker substances for quality control worldwide. The analytical methods currently used to detect these two compounds unfairly penalize steamed and dried (red) P. ginseng preparations, because it has a lower content of those ginsenosides than white ginseng. To manufacture red ginseng products from fresh ginseng, the ginseng roots are exposed to high temperatures for many hours. This heating process converts the naturally occurring ginsenoside Rb1 and Rg1 into artifact ginsenosides such as ginsenoside Rg3, Rg5, Rh1, and Rh2, among others. This study highlights the absurdity of the current analytical practice by investigating the time-dependent changes in the crude saponin and the major natural and artifact ginsenosides contents during simmering. The results lead us to recommend (20S)- and (20R)-ginsenoside Rg3 as new reference materials to complement the current P. ginseng preparation reference materials ginsenoside Rb1 and Rg1. An attempt has also been made to establish validated qualitative and quantitative analytical procedures for these four compounds that meet International Conference of Harmonization (ICH) guidelines for specificity, linearity, range, accuracy, precision, detection limit, quantitation limit, robustness and system suitability. Based on these results, we suggest a validated analytical procedure which conforms to ICH guidelines and equally values the contents of ginsenosides in white and red ginseng preparations.

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.6
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• pp.715-724
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• 2022

With the enforcement of the infrastructure management act, the importance of utility tunnels that jointly accommodate life-lines such as electricity, communication, water supply, and heating facilities has increased. The currently applied utility tunnel maintenance system is managed in an accident-preventive safety-based evaluation method. However, this evaluation method has limitations in effective maintenance. In this study, performance evaluation items were derived through the Delphi method to suggest a criterion for quantitatively evaluating the performance of utility tunnels, and the weights for each item were calculated through the Analytic Hierarchy Process (AHP) method. In the future, it is judged that a more reasonable performance evaluation standard of utility tunnel can be prepared if modifications and supplements are made through field application.

• Journal of Soil and Groundwater Environment
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• v.26 no.6
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• pp.65-73
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• 2021

Since the amount of red mud, generated from aluminum smelting process as a by-product, has increased worldwide, the recycle and metal resource recovery from the red mud is becoming more important. In this study, in order to recycle the red mud as a soil stabilizer to remediate arsenic contaminated soils, neutralization of red mud was investigated. Red mud was neutralized by washing with distilled water and NaCl, CaCl₂, FeCl₃, and HCl solutions and heating at 200-800℃, and arsenic stabilization characteristics in soils were evaluated with the neutralized red mud. Although washing with distilled water was not effective in neutralizing red mud, the application of the washed red mud to soils lowered the soil pH compared to the application of untreated red mud. Among NaCl, CaCl₂, FeCl₃, and HCl solutions, washing with FeCl₃ showed the most effective in lowering pH of the red mud from pH 10.73 to pH 4.26. Application of the neutralized red mud in soils resulted in quite different arsenic stabilization efficiency depending on soil samples. In M1 soil, which showed relatively high arsenic stabilization efficiency by untreated red mud, the neutralization of red mud resulted in little effect on arsenic stabilization in soil. On the other hand, in M2 soil, which showed low arsenic stabilization efficiency by untreated red mud, the neutralization of red mud increased arsenic stabilization significantly. Soil characteristics such as clay minerals and pH buffering capacity seemed to affect reactions between red mud and soils, which resulted in different effects of the red mud application on soil pH and arsenic stabilization efficiencies.

• Journal of Ginseng Research
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• v.43 no.1
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• pp.27-37
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• 2019

Background: The structural conversions in ginsenosides induced by steaming or heating or acidic condition could improve red ginseng bioactivities significantly. In this paper, the chemical transformations of red American ginseng from fresh Panax quinquefolium L. under steaming were investigated, and the possible mechanisms were discussed. Methods: A method with reversed-phase high-performance liquid chromatography coupled with linear ion trap mass spectrometry ($HPLC-MS^n$)-equipped electrospray ionization ion source was developed for structural analysis and quantitation of ginsenosides in dried and red American ginseng. Results: In total, 59 ginsenosides of protopanaxadiol, protopanaxatriol, oleanane, and ocotillol types were identified in American ginseng before and after steaming process by matching the molecular weight and/or comparing $MS^n$ fragmentation with that of standards and/or known published compounds, and some of them were determined to be disappeared or newly generated under different steaming time and temperature. The specific fragments of each aglycone-type ginsenosides were determined as well as aglycone hydrated and dehydrated ones. The mechanisms were deduced as hydrolysis, hydration, dehydration, and isomerization of neutral and acidic ginsenosides. Furthermore, the relative peak areas of detected compounds were calculated based on peak areas ratio. Conclusion: The multicomponent assessment of American ginseng was conducted by $HPLC-MS^n$. The result is expected to provide possibility for holistic evaluation of the processing procedures of red American ginseng and a scientific basis for the usage of American ginseng in prescription.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.9-13
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• 2019

In this study, a miniature thin film-patterned heater was fabricated on a silicon substrate using semiconductor process technology and the thermal characteristics of the applied voltage, power, and temperature of the thin film heater were measured and analyzed. The temperature of the thin film pattern heater increased with increasing power, but the temperature increase rate was gradual at high power intervals. The characteristics of the high temperature section of the platinum thin film-patterned heater were analyzed using the heat resistance model under atmospheric and vacuum conditions. The thermal resistance measured in a vacuum atmosphere was 0.79 [K/mW] higher than the heat resistance value 0.69 [K/mW] in air. The temperature of the thin film pattern heater can be maintained at a low power in a vacuum rather than in air, and these results are expected to be utilized in the structural design of a thin film-patterned heater element.