• Textile Coloration and Finishing
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• v.13 no.4
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• pp.234-240
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• 2001

In order to improve the washing fastness of dyed polyester artificial suede fabric, it was dyed by using auto and anthraguinone type disperse dyes and treated with 3 different reduction clearing methods. The reduction clearing methods used in this study were normal alkaline reduction clearing, $N_2$ gas replacement method, and ultrasonic treatment during normal reduction clearing. The results were as followings ; The washing fastness property of dyed polyester artificial suede fabric was slightly improved by reduction clearing with $N_2$ gas replacement or with ultrasonic treatment comparing with normal alkaline reduction clearing. It was found that the use of $N_2$ gas replacement or ultrasonic treatment during reduction clearing eave effective removal of unfixed dyes on the fiber surface. We also obtained that the azo type disperse dye on polyester artificial fabric suede fabric showed higher wash fastness than anthraquinone type disperse dye.

• Textile Coloration and Finishing
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• v.13 no.3
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• pp.180-187
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• 2001

Generally, polyester microfiber has much greater dye uptake than that of regular ones. In spite of high dye up-take visual shade depth of dyed fabric decreases with smaller denier, which results in poor washing fastness of dyed fabric. In this study, in order to investigate the washing fastness, polyester microfiber fabric was dyed by using two type of disperse dyes and treated with 3 different reduction clearing methods. The reduction clearing methods in this study are normal alkaline reduction clearing, $N_2$ gas replacement method, and ultrasonic treatment during reduction clearing. The results were as followings ; The most important factors affecting the washing fastness of polyester artificial suede fabric were found to be the reduction clearing method, the chemical structure of used disperse dyes and the structure and denier of fibers. It was also obtained that the heat treatment of dyed fabric decreased the washing fastness due to the dye migration from inner phase to surface.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.21 no.2
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• pp.99-102
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• 2011

Objectives: Acetone/triacetine method for clearing cellulose ester membrane (CEM) filter has been a popular method for air-borne asbestos analysis. However, as a weakness of this method, it is time consuming to analyses asbestos samples after sampling. Crystalclear method can be used to analyses asbestos samples promptly after sampling. Although a strength of crystal clear method exists, there was little valid studied for the method. This study was conducted to compare acetone/triacetine method with crystalclear one for analysing asbestos sample. Methods: Test samples made in three different concentration ranges(low, medium and high concentration) were analysed by phase contrast microscopy after acetone/triacetine and crystalclear method treatment respectively. Results: We did not find statistical difference in analysed results between two methods, which were conducted in three different concentrations ranges. Conclusions: We concluded that crystalclear method can be used as clearing method for air-borne asbestos analysis instead of acetone/triacetine method.

• Journal of Korean Medical classics
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• v.22 no.2
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• pp.285-292
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• 2009

The purpose of this study is to introduce heat-clearing music therapy[淸熱音樂療法] as one of the 17 kinds of oriental medicine music therapy. The heat-clearing music therapy[淸熱音樂療法] can be applied to certain types of syndromes. The representative syndromes are flaring-up of the heart Fire[心火], rising of the liver Yang[肝陽], and fidgetiness due to deficiency of Eum(陰, Yin). Metal-Gi[金氣] music and Water-Gi[水氣] music are mainly used in heat-clearing music therapy, The patients with the case of flaring-up of the heart Fire[心火] may listen to Metal-Gi[金氣] music. For the patient with rising of the liver Yang[肝陽], relieving constraint music therapy can be used. In other cases with patients with fidgetiness due to deficiency of Eum, replenishing vital essence music therapy can be used. This study describes the theory of heat-clearing music therapy[淸熱音樂療法] that has a good possibility as a new method of oriental medical treatment.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.736-740
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• 2004

In order to overcome the problems of simulation methods, the power system transient stability assessment method using critical fault clearing time functions has been developed. Using the above method, this paper has developed the new method which can assess accurately and efficiently the effects of control and protection systems on transient stability which is the most important characteristic to assess in power systems. At first, critical fault clearing time functions CCT(W:load) are defined by taking notice of the fact that transient stability is mainly controlled by fault clearing time and load. Next, the method to be enable to assess accurately and efficiently the effects of control and protection systems on transient stability has been newly developed by using the above functions. Finally, it has been applied to the effect assessment in the occurrence of a three-phase fault in a model power system. Results of application have been clarified its effectiveness.

• Journal of Electrical Engineering and Technology
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• v.8 no.2
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• pp.197-205
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• 2013

Real time transient stability assessment mainly depends on real-time prediction. Unfortunately, conventional techniques based on offline analysis are too slow and unreliable in complex power systems. Hence, fast and reliable stability prediction methods and simple stability criterions must be developed for real time purposes. In this paper, two new methods for real time determining critical clearing time based on clustering identification are proposed. This article is covering three main sections: (i) clustering generators and recognizing critical group; (ii) replacing the multi-machine system by a two-machine dynamic equivalent and eventually, to a one-machine-infinite-bus system; (iii) presenting a new method to predict post-fault trajectory and two simple algorithms for calculating critical clearing time, respectively established upon two different transient stability criterions. The performance is expected to figure out critical clearing time within 100ms-150ms and with an acceptable accuracy.

• Magazine of the Korean Society of Agricultural Engineers
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• v.14 no.1
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• pp.2535-2548
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• 1972

Instead of fertilizing the lands they moved to find other fertile lands and lived a feudal life agriculture and various machincs played a main role in the land reclamation. The best method of land clearing, the time and capacity in the operation and the effect of growing crops should systematically analized prior to the time of 3rd Five-year Economic Development(1972-1976) in order to cultivate 210,000ha of wasteland or the modernization of our country. The present study was investigated to find out a new working-system of mechanical land clearing and development of fertile soil. The results are as follows: 1) The first stage of productive power increases when weeds were mixed soil in the land clearing work in order to supply organic materials and to make soil swollen instead of burning or just removing. 2) The equipments such as bulldozers, harrows, power tillers and so on should be prepared in order to do a systematic work in the land clearing. 3) The work of pulling-up roots is dependent upon the forms of roots spreading under the ground. The work of the pulling-up of the straight roots was most difficult. But before the roots are pulling-up we do not know the forms of roots. 4) The cutting of soil from upside to under side land clearing method (II) Spent 6 hr 7 min 43 sec per 1 Danbo in doing land clearing and control method spent 4 hr 52 min 30 sec per 1 Danbo in doing land cearing. No significant difference could be found between II treatment type and I treatment type. 5) The volume of soil carried by bulldozer $270.38m^3$ per 1 Danbo in I type and in II type, $368.58m^3$ per 1 Danbo or about 36% increased in II type then in I type. But that is not a significant difference when considering the whole productive power of soil. 6) The land clearing of terrace by bulldozers cannot escape making the embankment slope of about $45^{\circ}$, and 25.3% should be decreased in the area. It is recommended to make use of the embankment slope by planting grass for cows. 7) The time of retary tilling increased 2.3 times or 1 hr 42 min 22 sec per 1 Danbo compared to the timesrequired in the harrowing. Because it mixed the Organic matter on ground and the harrowing of subsoil. 8) The havest of pasture growing on the land reclamation in natural slope is as follows. (a) The none fertilizers with reclaimed block of productivity decresed 1/10 than that of the farmland. Therefore the none fer tilizing in the cultivated pasture is unprofitable. (b) The havest of the manured IV treatment block was the best not only in the kinds of fertilizers but also in the kinds of pasture grass.

• Medical Lasers
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• v.10 no.3
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• pp.146-152
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• 2021

Background and Objectives Although lasers have been widely applied in tissue treatment, the light penetration depth in tissues is limited by the tissue turbidity and affected by its absorption and scattering characteristics. This study investigated the effect of using an optical clearing agent (OCA) on tissue to improve the therapeutic effect of 1064 nm wavelength laser light by reducing the heat generated on the skin surface and increasing the penetration depth. Materials and Methods A diode laser (λ = 1064 nm) was applied to a porcine specimen with and without OCA to investigate the penetration depth of the laser light and temperature distribution. A numerical simulation using the finite element method was performed to investigate the temperature distribution of the specimen compared to ex-vivo experiments using a thermocouple and double-integrating sphere to measure the temperature profile and optical properties of the tissue, respectively. Results Simulation results showed a decrease in tissue surface temperature with increased penetration depth when the OCA was applied. Furthermore, both absorption and scattering coefficients decreased with the application of OCA. In ex-vivo experiments, temperatures decreased for the tissue surface and the fat layer with the OCA, but not for the muscle layer. Conclusion The use of an OCA may be helpful for reducing surface heat generation and enhance the light penetration depth in various near-infrared laser treatments.

• Proceedings of the KIEE Conference
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• 2001.11b
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• pp.73-76
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• 2001

This paper presents a new systematic contingency selection, screening and ranking method for on-line transient security assessment. Transient stability of a particular generator is influenced most by fault near it. Fault at the transmission lines adjacent to the generators are selected as contingency. Two screening methods are developed using the sensitivity of modal synchronizing torque coefficient and computing an approximate critical clearing time(CCT) without time simulation. The first method, which considers only synchronizing power, may mislead in some cases since it does not consider the acceleration power. The approximate CCT method, which consider both the acceleration and deceleration power, worked well. Finally the Single Machine Equivalent(SIME) method is implemented using IPLAN of PSS/E for detailed stability analysis.

• The Transactions of the Korean Institute of Power Electronics
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• v.24 no.5
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• pp.349-355
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• 2019

A grid-connected inverter with critical loads should be able to supply a stable voltage to critical loads at mode change and during clearing time while detecting unintentional islanding. This study proposes a mode transfer method for a grid-connected inverter with critical loads. The proposed method, which integrates the grid-connected and islanded mode control loops into one control block, provides an autonomous and seamless mode transfer from the current control to the voltage control. Therefore, the proposed scheme can supply a stable voltage to critical loads at mode change and during clearing time. Experimental results are provided to validate the proposed method.