• Fashion & Textile Research Journal
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• v.15 no.5
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• pp.808-814
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• 2013

In this study, The mixture of three kinds of pre-treatment agents, Carboxymethyl cellulose sodium salt(CMC), Sodium alginate and Dextrin, have been prepared for the better coloration of digital textile printing. To get sharpness of outline during digital printing process, the optimal formulation is the CMC and Sodium alginate mixture 1:1 ratio by volume. Cyan, Yellow, and Black colours are excellent on the Sodium alginate mixtures. But, Magenta is excellent in the CMC and Dextrin mixture. Sharpness and printability are closely related to viscosity of the mixture. The most optimal sharpness of outline achieved with a consideration of coloring, and field operations account for production when the viscosity of the mixed pre-treatment agent approximately is 10~13 cSt. Change in shade and staining of wash fastness for all the treated samples with the mixtures rated 4-5 grade. Both dry rubbing fastness to shade change and staining are good in the treated samples, whereas wet rubbing fastness rated 2-3 grade. To improve wet rubbing fastness, the Sodium alginate and Dextrine mixture, which rated 3-4 grade for Black color, is applicable. With exception of 3 rating to black color, Light fastness is 4 rating for the remaining three colors in the regardless of treatment condition and mixing of the pre-treatment agent. Dry cleaning fastness of all samples are also 4-5 rating.

• ETRI Journal
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• v.16 no.1
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• pp.45-57
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• 1994

The effects of reactive ion etching (RIE) of $SiO_2$ layer in $CHF_3/C_2F_6$ on the underlying Si surface have been studied by X-ray photoelectron spectroscopy (XPS), secondary ion mass spectrometer, Rutherford backscattering spectroscopy, and high resolution transmission electron microscopy. We found that two distinguishable modified layers are formed by RIE : (i) a uniform residue surface layer of 4 nm thickness composed entirely of carbon, fluorine, oxygen, and hydrogen with 9 different kinds of chemical bonds and (ii) a contaminated silicon layer of about 50 nm thickness with carbon and fluorine atoms without any observable crystalline defects. To search the removal condition of the silicon surface residue, we monitored the changes of surface compositions for the etched silicon after various post treatments as rapid thermal anneal, $O_2$, $NF_3$, $SF_6$, and $Cl_2$ plasma treatments. XPS analysis revealed that $NF_3$ treatment is most effective. With 10 seconds exposure to $NF_3$ plasma, the fluorocarbon residue film decomposes. The remained fluorine completely disappears after the following wet cleaning.

• Mineral and Industry
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• v.25
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• pp.1-10
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• 2012

In this present work, the froth flotation of lithium ore from Boam mine located in Wooljin, Kyungbuk has been carried out to produce high-grade lithium concentrate. The sample ore-Lepidolite mainly contained silicate mineral (quartz, muscovite) and calcite. In consequences of the experiment, it has been possible to obtain relatively high-grade lithium while using anionic acid (oleic acid) to remove calcite before the froth flotation for lithium concentrate. Among the amines collectors (Armac-T, Armac-C, Armafloat-18, Armafloat-1597), Armac-T has been relatively effective than another ones. Under the optimum condition (collector : Armac-T 100g/t, frother : AF65 50g/t, depressants : $Na_2SiO_3$ 600g/t and Lactic acid 100g/t, pulp density : 20%, pH 5.5, number of cleaning : 2), it has been obtained relatively high-grade lithium concentrate ($Li_2O$) with recovery of 80.3% and with grade of 4.33%.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2000.11a
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• pp.1-2
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• 2000

In chip plating, several parameters must be taken into consideration. Current density, solution concentration, pH, solution temperature, components volume, chip and media ratio, barrel geometrical shape were most likely found to have an effect to the process yields. The 3 types of barrels utilized in chip plating industry are the onventional rotating barrel, vibrational barrel(vibarrel), and the centrifugal type. Conventional rotating barrel is a close type and is commonly used. The components inside the barrel are circulated by the barrel's rotation at a horizontal axis. Process yield has known to have higher thickness deviation. The vibrational barrel is an open type which offers a wide exposure to electrolyte resulting to a stable thickness deviation. It rotates in a vertical axis coupled with multi-vibration action to facilitate mixed up and easy transportation of components. The centrifugal barrel has its plated work centrifugally compacted against the cathode ring for superior electrical contact with simultaneous rotary motion. This experiment has determined the effect of barrel vibration intensity to the plating thickness distribution. The procedures carried out in the experiment involved the overall plating process., cleaning, rinse, Nickel plating, Tin-Lead plating. Plating time was adjusted to meet the required specification. All other parameters were maintained constant. Two trials were performed to confirm the consistency of the result. The thickness data of the experiment conducted showed thatbthe average mean value obtained from higher vibrational intensity is nearer to the standard mean. The distribution curve shown has a narrower specification limits and it has a reduced variation around the target value. Generally, intensity control in vi-barrel facilitates mixed up and easy transportation of components. However, it is desirable to maintain an optimum vibration intensity to prevent solution intrusion into the chips' internal electrode. A cathodic reaction can occur in the interface of the external and internal electrode. 2H20 + e $\rightarrow$M/TEX> 20H + H2.. Hydrogen can penetrate into the body and create pressure which can cause cracks. At high intensity, the chip's motion becomes stronger, its contact between each other is delayed and so plating action is being controlled. However, the strong impact created by its collision can damage the external electrode's structure there by resulting to bad plating condition.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.4_2
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• pp.617-626
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• 2020

The drilling mud is essentially used in oil and gas development. There are several roles of using the drilling mud, such as cleaning the bottomhole, cooling and lubricating the drill bit and string, transporting the cuttings to the surface, keeping and adjusting the wellbore pressure, and preventing the collapse of the wellbore. The fragments from rocks and micro-sized bubbles generated by the high pressure are mixed in the drilling mud. The systems to separate those mixtures and to keep the uniformly maintained quality of drilling mud are required. In this study, the simulation is conducted to verify the performance of the mud tank's agitation capacity. The primary role of the mud tank is the mixing of mud at the surface with controlling the mud condition. The container type is chosen as a mud tank pursuing efficient transport and better management of equipment. The single- and two-phase simulations about the agitation in the mud tank are performed to analyze and identify the inner flow behavior. The convergence of results is obtained for the vertical- and axis-direction velocity vector fields based on the grid-dependency tests. The mixing time analysis depending on the multiphase flow conditions indicates that the utilization of a two-stepped impeller with a smaller size provides less time for mixing. This study's results are expected to be utilized as the preliminary data to develop the mixing and integrating equipment of the onshore drilling mud system.

• Journal of The Korean Society of Agricultural Engineers
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• v.61 no.6
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• pp.21-30
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• 2019

Livestock odor is comprised of mixed type of odorous compounds. Among these, ammonia ($NH_3$) and hydrogen sulfide ($H_2S$) are the two known major odor causing substances. Because high odor concentration reduces productivity of livestock and causes damage to the surrounding communities, quantitative analysis is needed to manage the odor inside and outside the livestock facilities. It is also necessary to evaluate odor dispersion according to the distance between the receptors taking into account the influence of odor source and weather condition. Therefore, in this study, we tried to evaluate the internal environment and odor dispersion from experimental pig house considering weather conditions. An experimental farm was specifically selected to eliminate the interference of odors generated by adjacent farms. $NH_3$ and complex odor were quantitatively analyzed using a gas detector and air dilution sensory method. The concentration of $NH_3$ and complex odor in pig house showed a distinct concentration difference according to the cleaning and ventilation conditions. $NH_3$ concentration and complex odor was lower than emission standard in the pig house and at the site boundary. The average $NH_3$ concentration (P1~P3) and the $NH_3$ concentration at the site boundary (S1) were strongly correlated with R=0.77. While the correlation for complex odor inside and at the site boundary had R=0.52. The correlation coefficient between $NH_3$ and the complex odor was 0.80.

• Journal of Biosystems Engineering
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• v.43 no.4
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• pp.379-385
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• 2018

Purpose: Postharvest handling of onions (harvesting, cleaning, grading, cooling, storing, and transport) should be performed continually to reduce costs and improve quality. The purpose of this study is to a) determine the design parameters and operating conditions of anion auto-dumping that constitutes a key component of the postharvest bulk handling machinery system, and b) to perform a performance test with the auto-dump prototype system. Methods: Kinematic analyses and computer simulations of the auto-dump mechanism were applied to analyze the operating conditions and design parameters. Results: The optimum working condition for the auto-dump was determined from kinetic analyses. In addition, the interaction between the velocity of the hydraulic cylinder and the angular velocity of the auto-dump were analyzed in order to control the bulk handling machinery system. The acting forces and optimum operating conditions of the hydraulic cylinder were determined by analyzing the forces related to the mass of inertia of the auto-dump assembly during rotation. The method of controlling the feeding rate of onions in terms of the uniformity of the stacking pattern and the control of the entire system was better than the two-stage method of controlling the rotational speed of the auto-dump. Based on the performance test with the prototype for the auto-dump, the stacking pattern and rigidity of the system were analyzed. Conclusions: These results would be of great importance in the postharvest bulk handling machinery system for onions.

• Fashion & Textile Research Journal
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• v.21 no.5
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• pp.640-655
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• 2019

Technology status was investigated by analyzing patents and development cases of wearable robots. Development direction of wearable robot for wearability was also suggested by understanding the problems of wearability from development cases through the FGI technique. The number of patents per technical field was the most in the field of strength support, but AI in the technology field was different in each country; Korea was found to be poor in the category of daily living assistance. The number of patents by technology category was the most in the category of muscular strength assistance. However, the values of AI in the technology category were different in each country; Korea was found to be poor in the category of daily living assistance. Development cases were focused on rehabilitation, so development is not fulfilled uniformly by use purpose. By wearing body parts, robots with single function type were mainly developed. Rigid material robots were mainly developed. It was confirmed that wearable robot technology is not developed evenly in the category of application because it is in the early stage of the technical proposal and centered on main performance improvement. We derived twelve wearable conditions for wearable robots: Shape and Size Appropriateness, Movement Appropriateness, Composition Appropriateness, Physiological Appropriateness, Performance Satisfaction, Ease of Operation, Safety, Durability, Ease of Dressing, Ease of Cleaning, Portability and Ease of Storage and Appearance Satisfaction. Finally, the development direction of a wearable robot for each wearable condition was suggested.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2001.06a
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• pp.3-3
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• 2001

Recently TiN, TiAlN, CrN hardcoatings have adapted many industrial application such as die, mold and cutting tools because of good wear resistant and thermal stability. However, in terms of high speed process, general hard coatings have been limited by oxidation and thermal hardness drop. Especially in the case of PCB drill, high speed cutting and without lubricant process condition have not adapted these coatings until now. Therefore more recently, superhard nanocomposite coating which have superhard and good thermal stability have developed. In previous works, WC-TiAlN new nanocomposite film was investigated by cathodic arc ion plating system. Control of AI concentration, WC-TiAlN multi layer composite coating with controlled microstructure was carried out and provides additional enhancement of mechanical properties as well as oxidation resistance at elevated temperature. It is noted that microhardness ofWC-TiA1N multi layer composite coating increased up to 50 Gpa and got thermal stability about $900^{\circ}C$. In this study WC-TiAlN nanocomposite coating was deposited on PCB drill for enhancement of life time. The parameter was A1 concentration and plasma cleaning time for edge sharpness maintaining. The characteristic of WC-TiAlN film formation and wear behaviors are discussed with data from AlES, XRD, EDS and SEM analysis. Through field test, enhancement of life time for PCB drill was measured.

• Proceedings of the Membrane Society of Korea Conference
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• 1997.06a
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• pp.207-231
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• 1997

The use household water purifier is continuously increasing due to the distrust of the piped, rap water, which may be caused by the deterioration of water quality and water supply facilities in Korea. The water purifier distributing in the domestic market is the membrane type that composes of membrane as a basic filter, sediment filter as a prefilter and activated carbon filter instead of one purifying water system. The membrane type using as a water cleaning system is mainly the method of micro filtration(NIF) as well as ultra filtration(UF) and reverse osmosis(RO). The types of MF and UF are using to remove suspended solids and virus, and RO is using to remove ionic compound in chemical organic compounds. At the beginning the household water purifier was imported as end-product or assembled by only importing module from small businesses in Korea. Therefore, people was hard to confide in the product quality because the sales policy and management of water purifier by small business were not effectively organized. However, the defects of water purifier having up to now ate improving by the efforts of special branches of water purifier and large enterprises, and new great products are developing and producing. To develop the best quality product of water purifier in Korea, it should be considered seasonal water characteristrics rather than any other condition. For example, the water purifier can be affected by the water temperature change, increase of suspended solids in the rainy season and inflow of raw water having concentration in a dry season. The subject we have to investigate in the future is to develop the water purifying system adaptable in Korea which can treat the water quality using close analyses of local and seasonal water characteristics.