• The Transactions of the Korean Institute of Electrical Engineers B
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• v.54 no.3
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• pp.111-119
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• 2005

In the magnetic fluid linear pump, the pumping forces and pumping speed mainly depend on the current patterns. In this research, a new design to reduce the discontinuities of the pumping forces of the MFLP was studied. Continuous pumping of the newly designed MFLP by using AC current increases pumping efficiency and reduces the pumping force. Forming shapes of the magnetic fluid at the intermediate state were computed and compared to measurement. Since the back flow of the fluid is reduced remarkably, 4 yoke's AC driving is more efficient than 7 yoke's DC driving. The size, weight and pumping discontinuity are also reduced.

• Plant Resources
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• v.7 no.2
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• pp.155-158
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• 2004

Activate charcoal (AC) can be utilized as a soil conditioner in agricultural crop areas. This study was conducted to investigate the effect of AC on growth and yield of Zingiber mioga ROSC as affected by different amounts of AC. The results obtained are summarized as follows. Growth characteristics including plant height and leaf length were the highest when activated charcoal added with 10-30%, suggesting that optimum amount of activated charcoal was ranged from 10 to 30%. Growth and enlargement of the root were improved by 10% AC with higher rhizome length and weight.

• Herbal Formula Science
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• v.21 no.1
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• pp.161-176
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• 2013

Objectives : To clarify the anti-arthritic activity of Ostericum koreanum Maxim. (OS) plus Aralia continentalis Kitagawa (AC) in vivo. Methods : All mice were immunized with bovine type II collagen. After a second collagen immunization, mice were treated with OS plus AC once a day for 7 weeks. Oral administration of OS plus AC (200 or 50 mg/kg) significantly suppressed the progression of CIA, which extend is comparable to that of methotrexate (MTX, 0.3 mg/kg), a positive control. The severity of arthritis within the knee joints was evaluated by histological assessment of cartilage destruction and pannus formation. Results : Administration of OS plus AC significantly suppressed the progression of CIA and inhibited the production of TNF-${\alpha}$ and IL-6 in serum. The erosion of cartilage was dramatically reduced in mouse knees after treatment with OS plus AC. In conclusion, our results demonstrates that OS plus AC significantly suppressed the progression of CIA and that this action was characterized by the decreased production of IL-6, IFN-${\gamma}$ and collagen II specific antibody in serum, CD3+CD69+ T cells, MHC class II+/CD11c+ (in DLN), CD11b+Gr-1+ cells (in PBMC), CD11b +Gr-1+ cells, B220+/CD23+ (in paw joint). Conclusions : The the levels of IFN-${\gamma}$ in the culture supernatant of splenocytes stimulated with CD3/CD28 or collagen were dramatically decreased, while those of IL-4 was increased. In the serum of OS and AC-treated mice, the levels of IgM RA factor were decreased.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2000.02a
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• pp.97-100
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• 2000

Superconducting power cable is one of the most promising energy application of high-Tc superconductors (HTS). Thus, we investigated previously the characteristics on electrical and mechanical Bi-2223 Ag sheathed tape. And a prototype HTS cable have been designed, constructed and tested. The result shows that the transport current of HTS cable (1, 19-filament) in LN2 was 116[A], 240[A], respectively. And AC loss of HTS cable(19-filament) was 1.7 [W/m] in 240 [A] loading.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.7
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• pp.1051-1057
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• 2003

This study is about controlled impurities, which make metal alloys, especially AC4CH alloy that is made by restraining 0.2％ Fe and Aluminum to make a matrix material. A metal matrix composite is produced using the squeeze casting method. The first step in the squeeze casting method is to add some organic binder including aluminum borate whisker into the matrix. After the fabrication of a metal matrix composite, each is individually appended to an inanimate binder such as SiO$_2$, Al$_2$O$_3$, and TiO$_2$. Through experiments the mechanical property changes were investigated between the metal matrix composite and AC4CH alloy. This study proves the superiority of the mechanical property of a metal matrix composites over AC4CH according to the previous tests and results that were mentioned above. One excellent property of matrix material composites is the infiltrated TiO$_2$ reinforcement. This material is a good substitute for the existing materials that are used in the development of industries today.

• Korean Journal of Acupuncture
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• v.28 no.2
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• pp.1-11
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• 2011

Objectives : The aim of this study was to examine the effect acupuncture by needle manipulation at acupoints, SP3 HT7, on the blood pressure and renin and atrial natriuretic peptide(ANP) in plasma, cardiac hypertrophy in hypertensive rats induced by two kidney one clip (2K1C). Materials and Methods : The experiments were performed on twenty-five Sprague Dawley rats, 2K1C hypertension model was prepared by constricting the left renal artery with a sliver clip. Animals were divided into five groups, control, AC-1a and AC-2a(acupuncture at SP3 HT7 bilaterally and the needle was twirled and rotated forward with the thumb and forefinger of the right hand 6 times), AC-3a(acupuncture at SP3 HT7 bilaterally and the needle was inserted in the opposite direction(body direction) as the channel runs), AC-4a(acupuncture at SP3 HT7 bilaterally and the needle was inserted in the opposite direction(body direction) as the channel runs and the needle was twirled and rotated forward with the forefinger of the right hand 6 times). The treatments were started on the 4 week after inducing 2K1C, and they were performed two times a week for 3 weeks in rats. Results : The results are that The blood pressure was significantly decreased at 4 times in Acu-1a, The cardiac hypertrophy was significantly decrease in Acu-2a and Acu-3a. The activity of plasma renin was decreased in all groups without control and Acu-1a, and that of plasma ANP was decrease in Acu-2a and Acu-3a than control group. Conclusions : These results suggest that acupuncture on SP3 HT7 mostly cause significant changes on controlling renal hypertension induced by 2K1C in the rats.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.51 no.7
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• pp.406-412
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• 2002

This paper presents a novel transformer with a new plastic magnetic core for switching power supplies. The proposed plastic magnetic core was realized using a simple manufacturing process and it can be easily designed with various shapes, suggesting that the manufacturing cost of a power transformer can be reduced using the proposed plastic magnetic core. The possible application potentials of the proposed transformer a AC/DC adaptor utilizing a transformer with the plastic magnetic core are explored. The developed adaptor, that has a maximum power of 24W, switching frequency of 125kHz, and input voltage of 110/220V, has been successfully implemented. A maximum power conversion efficiency of the experimental converter was measured at 77%, and the output was regulated at 12V within 0.2% tolerance.

• Journal of the Korean Applied Science and Technology
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• v.30 no.1
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• pp.88-95
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• 2013

This study attempts to capture the low level carbon dioxide from indoor spaces using a granular activated carbon (WSC-470) which was modified with primary monoethanolamine. Adsorption capacity of the prepared adsorbents was evaluated for pure $CO_2$ flow and 3000 ppm as a function of MEA concentration and solvents such as distilled water, ethanol and methanol. The AC based adsorbents then were characterized in terms of pore structure by BET and chemical functionalities by XPS. While high concentration of MEA reduced specific surface area, porosity and micro pores, nitrogen content which can enhance the surface basicity was increased. The maximum adsorption capacity decreased comparing to the initial AC pellets, whilst the potential of selective adsorption amount at low level $CO_2$ was increased at 45% (0.73 mmol/g).

• Koreanishche Zeitschrift fur Deutsche Sprachwissenschaft
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• v.7
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• pp.105-125
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• 2003

Personal- und Reflexivpronomen stehen in einer komplementaren Beziehung zueinander. Die vorliegende Arbeit zeigt, welches von beiden Pronomen verschiedenen AcI-Konstruktionen jeweils richtig ist Vor allem stelle ich hier die These auf, dass Grammatik in erster Linie ein Regelwerk ist und dass dernzufolge $S\"{a}tze$ mit gleicher Struktur immer einheitlich und konsistent mit denselben Regeln $erkl\"{a}rt$ werden sollten: (1) a. Der Gefangen $l\"{a}sst$ den Polizisten auf ${\ast}sich_i/ihn_i$ achten. b. $Hans_i{\;}l\"{a}sst$ Maria zu $sich_i/{\ast}ihm_i$ kommen. (2) a. $Peter_i$ sieht Hans von ${\ast}sich_i/ihm_i$ betrogen. b. $Hans_i{\;}f\"{u}hlt$ die Freundin von $sich_i/{\ast}ihm_i$ weggezogen. Bei diesen Beispielen liegt der Verteilungsunterschied der Pronomina nicht an Grammatikregeln sondern am individuellen Sprachgebrauch. Ferner wird hier darauf hingewiesen, dass die AcI-Verben mit Ausnahme des Verbs lassen a1s 3-wertige Verben so wie die $S\"{a}tze$ in Beispiel (3) zu behandein sind D.h., die Struktur $f\"{u}r$ AcI-Konstruktionen sieht so aus wie (4b), nicht wie (4a). Betrachten wir dies noch einmal an einem Beispiel: (3) a. Ich sehe mich $m\"{u}de$ b. Ich $f\"{u}hle$ mich viel besser.

• Korean Journal of Materials Research
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• v.30 no.9
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• pp.458-464
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• 2020

Zinc-ion hybrid supercapacitors (ZICs) have recently been spotlighted as energy storage devices due to their high energy and high power densities. However, despite these merits, ZICs face many challenges related to their cathode materials, activated carbon (AC). AC as a cathode material has restrictive electrical conductivity, which leads to low capacity and lifetime at high current densities. To overcome this demerit, a novel boron (B) doped AC is suggested herein with improved electrical conductivity thanks to B-doping effect. Especially, in order to optimize B-doped AC, amounts of precursors are regulated. The optimized B-doped AC electrode shows a good charge-transfer process and superior electrochemical performance, including high specific capacity of 157.4 mAh g^-1 at current density of 0.5 A g^-1, high-rate performance with 66.6 mAh g^-1 at a current density of 10 A g^-1, and remarkable, ultrafast cycling stability (90.7 % after 10,000 cycles at a current density of 5 A g^-1). The superior energy storage performance is attributed to the B-doping effect, which leads to an excellent charge-transfer process of the AC cathode. Thus, our strategy can provide a rational design for ultrafast cycling stability of next-generation supercapacitors in the near future.