• Proceedings of the Korean Magnestics Society Conference
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• 2008.12a
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• pp.118.2-118.2
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• 2008

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.8
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• pp.563-569
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• 1999

Boron doped CdS films were prepared by chemical bath deposition using boric acid$(H_3BO_3)$ as donor dopant source, and their electrical, optical properties were investigated as a function of doping concentration. In addition, effects of boron doping of CdS films on characteristics of CdS/CdTe solar cells were investigated. Boron doping highly decreased the resistivity and slightly increased optical band gap of CdS films. The lowest value of resistivity was $2 \Omega-cm \;at\; H_3BO_3/Cd(Ac)_2$ molar ratio of 0.1. For the molar ratio more than 0.1, however, the resistivity increased because of decreasing carrier concentration and mobility and showed similar value for undoped films. The photovoltaic characteristics of CdS/CdTe solar cells with boron doped CdS film improved due to the decrease of the conduction band-Fermi level energy gap of CdS films and the series resistance of solar cell.

• Ecology and Resilient Infrastructure
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• v.8 no.1
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• pp.64-78
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• 2021

This study was conducted to find out the effect of the construction and operation of river-crossing structures on the habitat landscape characteristics in the Geum-gang River, South Korea. A total of three study reaches were selected in the downstream of the Daecheong Dam: the Buyong-ri reach, which is a control that is not affected by the construction and operation of the weir of the Four Rivers Project and Sejong-bo Weir reach and Gongju-bo Weir reach of the upper and lower sections of each weir that are affected by the weir construction and operation. The habitat type was classified, and then the structural characteristics of the landscape were analyzed using aerial photographs taken before and after the construction of the Daecheong Dam, before and after the construction of the weir, and before and after the weir gate operation. After the construction of Daecheong Dam in Geum River, the area of the bare land greatly decreased, and the area of grassland and woodland increased in the downstream of the dam. In addition, the patch number in the river landscape increased, the patch size decreased, and the landscape shape index and the habitat diversity increased. Therefore, after the construction of the dam, the bare land habitat was changed to a vegetated habitat, and the habitat was fragmented and diversified in the downstream of the dam. After the construction of the weirs, the area of open water increased by 18% in the Sejong-bo reach and by 90% in the Gongju-bo reach, and the landscape shape index of the open water decreased by 32% in the Sejong-bo reach and by 35% in the Gongju-bo reach, and the habitat diversity index decreased to 25% in the Sejong-bo reach and to 24% in the Gongju-bo reach. Therefore, the open water habitat was expanded, the shape of the habitat was simplified, and the habitat diversity decreased according to the construction of the weirs. After water-gate opening of the weir, the bare land that disappeared after the construction of the weir reappeared, and the landscape shape index and habitat diversity index increased in both terrestrial and open water habitats. Therefore, it was found that the landscape characteristics of the river habitats were restored to the pre-construction of the weir by the operation of the weir gate. The effect of weir gate opening was delayed in the downstream than in the upstream of the weir. Although the characteristics of the landscape structure in the river habitat changed due to the construction of the river-crossing structures, it is thought that proper technology development for the ecological operation of the structures is necessary as the habitat environments can be restored by the operation of these structures.

• Journal of the Korean Vacuum Society
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• v.7 no.2
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• pp.112-117
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• 1998

TiN has been investigated as a good candidate for a diffusion barrier of Cu. Therefore, in this study, the grain boundary diffusion of Cu in TiN film was investigated by X-ray photoelectron spectroscopy(XPS). In general, TiN has a columnar grain structure. In the relatively lower temperature, less than 1/3 of the melting point, it was observed that Cu diffused into TiN mainly along the grain boundaries of TiN. The grain size of TiN was measured by atomic force microscope (AFM). In order to estimate the grain boundary diffusion constants, we used the modified surface accumulation method. The activation energy, $Q_b$ was 0.23 eV, and the diffusivity, $D_{bo}$ was $5.5\times10^{-12{\textrm{cm}^2$/sec.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6369-6374
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• 2012

Vitexicarpin (3', 5-dihydroxy-3, 4', 6, 7-tetramethoxyflavone), a polymethoxyflavone isolated from Viticis Fructus (Vitex rotundifolia Linne fil.), has long been used as an anti-inflammatory herb in traditional Chinese medicine. It has also been reported that vitexicarpin can inhibit the growth of various cancer cells. However, there is no report elucidating its effect on human prostate carcinoma cells. The aim of the present study was to examine the apoptotic induction activity of vitexicarpin on PC-3 cells and molecular mechanisms involved. MTT studies showed that vitexicarpin dose-dependently inhibited growth of PC-3 cells with an $IC_{50}{\sim}28.8{\mu}M$. Hoechst 33258 staining further revealed that vitexicarpin induced apoptotic cell death. The effect of vitexicarpin on PC-3 cells apoptosis was tested using prodium iodide (PI)/Annexin V-FITC double staining and flow cytometry. The results indicated that vitexicarpin induction of apoptotic cell death in PC-3 cells was accompanied by cell cycle arrest in the G2/M phase. Furthermore, our study demonstrated that vitexicarpin induction of PC-3 cell apoptosis was associated with upregulation of the proapoptotic protein Bax, and downregulation of antiapoptotic protein Bcl-2, release of Cytochrome c from mitochondria and decrease in mitochondrial membrane potential. Our findings suggested that vitexicarpin may become a potential leading drug in the therapy of prostate carcinoma.

• Journal of Acupuncture Research
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• v.33 no.4
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• pp.1-6
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• 2016

Objectives : The purpose of this report is to inform readers of the important aspects of about acupuncture and the process of Hwangjenaegyeong Yongchu. Methods : We researched the word 'acupuncture' through Hwangjenaegyeong Youngchu. We formed three categories according to the meanings of the key aspects of acupuncture in each sentence. Results : In Hwangjenaegyeong Youngchu, the meanings of the key aspects of acupuncture (刺鍼之要) are follows : 1. The key aspect of acupuncture(刺鍼之要) is to control Gi & Sin(調氣治神). 2. Before administering acupuncture, a doctor must know Meridian, acu-points, contraindication of nature, Bo-sa acupuncture(補瀉), Deug Gi(得氣), the role of the acupuncture needle(官鍼), the number of the needle, Gi & condition of patients, and pulse diagnosis. 3. For acupuncture, there are several things to be aware of : contraindication of acupuncture, deleteriousness of acupuncture, acu-points, and Bo-sa acupuncture(補瀉).

• Korean Journal of Pharmacognosy
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• v.11 no.1
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• pp.7-10
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• 1980

Antitumor activity test was achieved with 20 crude drugs which are folkmedicine and recorded in Dong-eu-bo-gam. Three crude drugs showed above 60% effect on life span of mouse and 5 crude drugs showed under 50% effect. After death, body weight was decreased with 3 crude drugs and increased with most other crude drugs, which were tested in this study. The solid cancer tissue weight was decreased slightly with 4 crude drugs.

• Journal of Embryo Transfer
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• v.15 no.3
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• pp.287-293
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• 2000

This study was undertaken to access the effects of collection method, room temperature at oocyte recovery and culture media on the oocyte quality, fertilization and cleavage rates of in vitro matured and fertilized oocytes of Korean native goats. Ovaries obtained from a slaughterhouse were transported to the laboratory and were divided into 2 groups. One group of ovaries was maintained at 30 to 35$^{\circ}C$ of the room temperature and another group was remained at 20 to $25^{\circ}C$ during oocyte recovery. The oocytes were recovered by follicle aspiration, slicing and aspiration+slicing methods from 3 groups of follicles according to size; <2 mm, 2 to 6 mm and >6 mm. The matured oocytes were inseminated with buck epididymal spermatozoa at a concentration of 3~3.5$\times$10$^{6}$ m1 and fertilization was identified when 2 pronuclei were present in the cytoplasm. Although the recovery rate per ovary obtained by the combination of follicle aspiration + slicing(19.6$\pm$2.2) method was higher than aspiration(11.7$\pm$1.1) and slicing(14.8$\pm$1.8) collection, optimal recovery according to oocyte grades resulted form ovarian slicing compared to aspiration or combined methods(P<0.05). However, no significant differences were found in the mean number(2.5$\pm$1.8; 3.3$\pm$3.3; 2.9$\pm$2.4) and the proportion of favorable oocytes(Grades I, II and III) recovered(31.6%, 36.0%, 36.4%,) according to follicle size(<2 mm; 2 to 6 mm; >6 mm). Fertilization rate was 60.0%, 67.7%, 70.6% and 56.4% and the proportion of embryos/zygotes was 11.1%, 7.1%, 5.0% and 2.8% in 20~$25^{\circ}C$/BO, 30~35$^{\circ}C$/BO, 20~$25^{\circ}C$/TALP and 30~35$^{\circ}C$ /groups, respectively.

• Journal of Animal Environmental Science
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• v.8 no.3
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• pp.129-134
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• 2002

This study was carried out to investigate the characteristic change of piggery slurry during the storage time and depth. The Piggery slurry was settled in a 10.0m diameter$\times$3.0m high storage tank for 6 months and then divided into three layers according to the storage time. The pollutants concentration, BODs(Biochemical Oxygen demand), CO $D_{Mn}$ (Chemical Oxygen demand) and SS(Suspended Solids) of the piggery slurry used in this study were 25,134, 15,840, 23,800mg/$\ell$, respectively. The initial fertilizer content of piggery slurry, N(Nitrogen), $P_2$ $O_{5}$(Phosphoric acid) and $K_2$O(Potassium oxide), were 0.69, 0.33, 0.40%, respectively. 6 months later, BO $D_{5}$, CO $D_{Mn}$ and SS of the Piggery slurry were 16,040, 8,098, 3,300mg/$\ell$ in top layer, 15,806, 8,309, 5,900mg/$\ell$ in middle layer and 39,530, 23,958, 51,000mg/$\ell$ in bottom layer, respectively. The fertilizer content of piggery slurry after 6 months, N, $P_2$ $O_{5}$ and $K_2$O, were 0.47, 0.07, 0.46% in top layer, 0.43, 0.08, 0.47% in middle layer and 0.60, 0.44, 0.40% in bottom layer, respectively. Consequently, in course of storage time, the pollutant concentration and fertilizer content were the highest in the bottom layer compared with the top and middle layer.

• Journal of the KSME
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• v.16 no.2
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• pp.84-91
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• 1976

An experimental investigation of the natural circulating boiling flow characteristic in three cases of annulus with different outer diameter, and the effect of annular gap size on the burnout behavior is presented. The experimental work was conducted for each case of test section at system pressure of $1kg/cm^2$ and inlet subcooling $0-20^{\circ}C$ in the full range of throttling ratio. As the result, the following facts were found. 1) With the increase of ${\Delta}T_{sub}$, $D_{2}$ and A/A_{o}$, $q_{BO}$ increases on the whole, and with the decrease of ${\Delta}T_{sub}$ and $D_{2}$, hydrodynamic instability is accelerated to happen prematually. 2)With the increase of ${\Delta}T_{sub}$, $D_{2}$ and A/A_{o}$ burnout characteristic shows the high velocitylow quality burnout, and with the decrease, low-velocity-high quality burnout. 3)With the decrease of A/A_{o}$, hyddrodynamic instability is singnificantly restrained and the difference of $q_{BO}$ in each $D_2$ under same condition is gradually reduced, finally converging into $1.9{\times}10^{5}kcal/m^{2}-hr$.