• Korean Journal of Pharmacognosy
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• v.45 no.3
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• pp.249-255
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• 2014

This study compared Bojungikgi-tang (BIT) and Yukmijihwang-tang (YJT) decoctions produced using the extractors made of various materials, such as glass, earthenware, and stainless steel, for 60, 90, and 120 min. The extraction yield was measured and the amounts of marker compounds in decoctions were determined by quantitative analysis using high performance liquid chromatography. The extraction yields of BIT decoctions produced by three extractors were not significantly different, whereas the extraction yield of YJT produced using glass extractor was significantly higher than that of YJT produced using earthenware extractor after 90 min. The amounts of most marker compounds were highest in BIT decoctions produced using glass extractor. However, variations of the amounts of marker compounds were observed in YJT decoctions and the volatile compound was not easily vaporized in YJT decoction produced using earthenware extractor. This study suggests that the extractor made of various materials may affect the extraction efficiency and the contents of marker compounds, especially in the decoction produced using earthenware extractor, although the results were dependent on the characteristics of herbal formula.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.3
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• pp.107-112
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• 2017

The purpose of this study was to develop an extractor to improve the effective ingredient of propolis. In order to improve the performance of conventional alcohol extraction at room temperature, a striking-type extractor used with a sprayed mist (alcohols, 95% alcohol) was developed for use at $40^{\circ}C$. Extraction of the effective ingredient of propolis was tested, and the resulting material was analyzed using a device. The extraction test of the mist spraying method indicated that the level of flavonoid was 1.56%, which is 1.5 times the 1.04% shown in existing data from a conventional stirred extractor. In addition, the extraction time can be reduced by half and the cost reduced by about 12.7% per year. It is confirmed that the extractor developed with a sprayed mist (alcohols, 95% alcohol) appears effective at the low temperature.

• Resources Recycling
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• v.22 no.6
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• pp.26-32
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• 2013

In order to recover Pt from the hydrochloric acid leaching solution of spent catalysts, bench scale Karr reciprocating column was employed. At an optimum flow rate and vibration frequency, iron and Pt was completely extracted by using TBP and Aliquat 336. At the same vibration frequency, iron and Pt was completely stripped by HCl and $HClO_4$ after adjusting the flow rate. In the case of extraction of HCl from the raffinate with TEHA, it was difficult to maintain the stability of the column extractor. A comparison of the operation results between column extractor and mixer-settler is reported.

• 한국기계연구소 소보
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• s.18
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• pp.5-19
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• 1988

Finite element scheme to analyze the vibration characteristics of the axisymmetric rotor system is developed. The rotor system of a large washer-extractor is analyzed as an example. Natural frequency obtained by FEM is in good agreement with experimental one by impact test. Also, parametric studies using FEM code developed are carried out for the investigation of the effects of the radii of the axis and the cylinder on the stiffness and the critical speed of the system. Larger radius of the axis makes the system stiffer and increases the critical speed at which the unbalance response has its maximum value. Whereas, the stiffness and the critical speed decrease at first and then increase as the radius of the cylinder increases.

• Journal of Institute of Control, Robotics and Systems
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• v.3 no.1
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• pp.89-93
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• 1997

This paper describes the automatic testing system developed for powder metallurgy process using the visual inspection, and its some internal algorithms. The system consists of one unit from each of the five types of units; feeding, slot, vision inspection, volumn counter, and inferior good extractor units. Some applications of the system to powder metallurgy process has shown the possibility of reducing the rework and increasing the efficiency of operation.

• Culinary science and hospitality research
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• v.14 no.3
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• pp.210-222
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• 2008

This study showed that the brown stock, which is the base of demi-glace sauce, extracted by using a high pressure heating extractor is more advantageous than that extracted by the traditional extraction method for the mass production. We compared the former with the latter in terms of minerals and free amino acids. The results of this study are summarized as follows. When mineral contents were compared, the brown stock extracted by high.pressure heating extraction showed the tendency of increase in mineral contents in proportion to heating temperature and heating time, but, from extraction temperature of 140$^{\circ}C$, the contents of K, Mg, Na and P decreased with the increase of extraction time. In addition, mineral contents in the brown stock extracted by high-pressure heating extraction were generally lower than those in brown stock extracted by the traditional extraction method. This result was produced probably because materials were added repeatedly in the traditional method. Amino acids contents in brown stock according to the extraction methods were also examined. They increased with the increase in the number of extractions in the brown stock extracted by the traditional method, and those in the brown stock extracted using a high pressure heating extractor increased with the increase in heating temperature and extraction time. The results of this study are expected to be useful as a practical material for the mass production of brown stock products.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.8
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• pp.705-713
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• 2014

In this paper, we propose a novel velocity ripple controller using phase compensation feedforward control. Velocity ripples result in many kinds of performance degradations in manufacturing machines, especially such as ultra-precision roll lathes. The generation of velocity ripple in constant velocity control comes from various causes, such as electrical torque ripples, mechanical worn out, inconsistent mass center, etc. Conventional researches about ripple is mainly for reducing torque ripple in actuator level, which is only one of reasons for velocity ripples, so in this study, we focus on eliminating velocity ripples in upper level controller using phase compensation feedforward controller. The proposed algorithm is composed of several modules, such as ripple extractor, phase adjuster and phase follower etc. The suggested algorithm can be easily extended, and it shows a superior performance in the experiments of ultra-precision roll lathes.

• Journal of Korea Foundry Society
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• v.39 no.1
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• pp.7-13
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• 2019

Few studies of large blooms over 700 mm thick among those used for the forging of raw materials have been reported. The cooling rate difference between the surface and the center of a large bloom is large, and the degradation of the mechanical properties is likely in cases involving excessively coarse precipitates resulted from the slow cooling rate of a large bloom after casting. Therefore, a schematic investigation of the growth behaviors of precipitates while varying their locations in blooms is necessary. The dissolution behaviors of precipitates were investigated by simulating a reheating process during which the bloom is heated to a high temperature. The segregation behavior of the as-cast large bloom was also investigated. Reheating specimens were obtained after an isothermal heat treatment at $1150^{\circ}C$ with various holding times to simulate the reheating process, with the samples undergoing a subsequent water quenching step. The precipitates were extracted using an electrolytic extractor and a particle size analysis was conducted with the aid of SEM, EDS, and TEM. In the present work, Al oxide, MnS and Nb carbide were mainly observed.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.552-556
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• 1994

It was aimed to study the chemical characteristics and volatile compounds of juices extracted by press (PE) and centrifugal extractors (CE). Citrons cut up cross direction were used as samples in PE. Proportion ratio of peel, flesh, and seed of citron were 43.9, 39.4 and 16.7%, respectively. Yield of juice increased with weight to 120g of citron fruit. pH, brix, pulp, oily materials, amino nitrogen and yield of juice extracted by CE were higher than those of juice by PE. Acidity and transmittance of juice extracted by PE were higher than those of juice by CE. Free sugars of citron juice were consisted of fructose, glucose and sucrose. Free sugar contents of juice by CE were twice as much as those of PE. Major volatile compounds of total steam distillation matters of citron juice extracted by PE were dl-limonene, ${\gamma}-terpinene\;{\beta}-farnesene$, sabinene, linalool, ${\beta}-myrcene$ and terpinolene, while those by CE were dl-limonene, ${\gamma}-terpinene$, sabinene, ${\beta}-myrcene,\;{\alpha}-pinene$, linalool and terpinolene. dl-Limonene and ${\gamma}-terpinene$ consisted of $73{\sim}83%$ of total volatile compounds. dl-Limonene of juice by CE increased about 6% that of juice by PE. ${\beta}-Farnesene$ were observed trace in juice by CE but presented in 7% in juice by PE. The results would suggested that chemical characteristics and volatile compounds of citron juice seemed to depend on extraction methods.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.3.2-3.2
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• 2011

In recent years, inkjet printing technology has received significant attention as a micro/nanofabrication technique for flexible printing of electronic circuits and solar cells, as well for biomaterial patterning. It eliminates the need for physical masks, causes fewer environment problems, lowers fabrication costs, and offers good layer-to-layer registration. To fulfill the requirements for use in the above applications, however, the inkjet system must meet certain criteria such as high frequency jetting, uniform droplet size, high density nozzle array, etc. Existing inkjet devices are either based on thermal bubbles or piezoelectric pumping; they have several drawbacks for flexible printing. For instance, thermal bubble jetting has limitations in terms of size and density of the nozzle array as well as the ejection frequency. Piezoelectric based devices suffer from poor pumping energy in addition to inadequate ejection frequency. Recently, an electrohydrodynamic (EHD) printing technique has been suggested and proposed as an alternative to thermal bubble or piezoelectric devices. In EHD jetting, a liquid (ink) is pumped through a nozzle and a strong electric field is applied between the nozzle and an extractor plate, which induce charges at the surfaces of the liquid meniscus. This electric field creates an electric stress that stretches the meniscus in the direction of the electric field. Once the electric field force is larger than the surface tension force, a liquid droplet is formed. An EHD inkjet head can produce droplets smaller than the size of the nozzle that produce them. Furthermore, the EHD nano-inkjet can eject high viscosity liquid through the nozzle forming tiny structures. These unique features distinguish EHD printing from conventional methods for sub-micron resolution printing. In this presentation, I will introduce the recent research results regarding the EHD nano-inkjet and the printing system, which has been applied to solar cell or thin film transistor applications.