• Korean Journal of Materials Research
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• v.11 no.7
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• pp.556-561
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• 2001

We prepared a new a SOS(silicon-on-silicide) wafer pair which is consisted of Si(100)/1000$\AA$-NiSi Si (100) layers. SOS can be employed in MEMS(micro- electronic-mechanical system) application due to low resistance of the NiSi layer. A thermally evaporated $1000\AA$-thick Ni/Si wafer and a clean Si wafer were pre-mated in the class 100 clean room, then annealed at $300~900^{\circ}C$ for 15hrs to induce silicidation reaction. SOS wafer pairs were investigated by a IR camera to measure bonded area and probed by a SEM(scanning electron microscope) and TEM(transmission electron microscope) to observe cross-sectional view of Si/NiSi. IR camera observation showed that the annealed SOS wafer pairs have over 52% bonded area in all temperature region except silicidation phase transition temperature. By probing cross-sectional view with SEM of magnification of 30,000, we found that $1000\AA$-thick uniform NiSi layer was formed at the center area of bonded wafers without void defects. However we observed debonded area at the edge area of wafers. Through TEM observation, we found that $10-20\AA$ thick amourphous layer formed between Si surface and NiSix near the counter part of SOS. This layer may be an oxide layer and lead to degradation of bonding. At the edge area of wafers, that amorphous layer was formed even to thickness of $1500\AA$ during annealing. Therefore, to increase bonding area of Si NiSi ∥ Si wafer pairs, we may lessen the amorphous layers.

• Weed & Turfgrass Science
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• v.6 no.4
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• pp.333-344
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• 2017

This study was conducted to examine the effect of cool-season grass overseeding on the green period, turf quality and density in zoysiagrass lawn. Treatments were perennial ryegrass (PR) overseeding ($60g\;m^{-2}$) on medium-leaf type zoysiagrass, Kentucky bluegrass (KB) overseeding ($20g\;m^{-2}$) on medium-leaf type zoysiagrass and narrow-leaf type zoysiagrass, and no overseeding on medium-leaf type zoysiagrass. Overseeding of KB or PR effectively provided quality improvement of zoysiagrass lawn by extending green-period about one month in spring and two months in fall season. PR overseeding showed quick green cover within 2-3 weeks but decreased the quality of overseeded zoysiagrass lawn during the summer season. Whereas, KB overseeding showed slow green cover taking two to three month after seeding but provided stable and good turf quality throughout the years. KB or PR overseeding significantly increased the turf density of zoysiagrass lawn except the period of summer depression of PR. The ground coverage of cool-season grasses ranged from 30 to 80% with considerable seasonal variation. As a result, KB and PR have their strengths and weaknesses as an overseeding material. Thus, the use of KB and PR as a mixture would provide better overseeding performance in zoysiagrass lawn.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.2
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• pp.193-204
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• 1998

The single crystal of the $LiTaO_3$has large electro-optic effects, so it is applied to optical switch, acousto-optic deflector, and optical memory device as hologram using photorefractive effect. In this study, optic-grade undoped $LiTaO_3$and Fe:LiTaO$LiTaO_3$single crystals were grown by the Czochralski method and optical transmission and absorption spectrums were measured in the wavelength of UV-VIS range. The curie temperature was determined with DSC and by measuring capacitance for the grown undoped crystal and ceramic powder samples of various Li/Ta ratio. In case of having a 48.6 mol% $Li_2O$ as a starting Li/Ta ratio, the results of concentration variations were below 0.01 mol% $Li_2O$ all over the crystal, so it was confirmed that $LiTaO_3$single crystals were grown under congruent melting composition having optical homogeneity. The curie temperature of the Fe:$LiTaO_3$crystal was increased with increased with increased doped Fe concentrations;by the ratio of $7.5^{\circ}C$ increase per Fe 0.1 wt%. Also, the optical transmittance was about 78 %, which was sufficient for optical device.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1294-1300
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• 2008

Nelumbo nucifera G. tea white breads were prepared by the addition of 0.01, 0.02, 0.03, and 0.04% hemicellulase to flour of the basic formulation. The experiments and control were then compared in terms of quality characteristics, including pH, total titratable acidity, fermentation power of dough expansion, specific volume, baking loss, moisture content, color, textural characteristics, external and internal surface appearances, and sensory qualities in order to determine the optimal ratio of hemicellulase in the formulation. There were no significant differences in pH and total titratable acidity of dough among the experiments. Fermentation power of dough expansion were increased as incubation time increased. Baking loss was the highest at the 0.04% addition level, while the lowest at the 0.01% level. As hemicellulase content increased, pH, hardness, and fracturability of bread decreased, while total titratable acidity, specific volume, and resilience increased. Water content and lightness were the highest in the control bread samples, and yellowness was maximal in the 0.01% group. Bread made by the addition of hemicellulase had significantly higher greenness and flavor than the control group. Color, consistency, and springiness of crumb, density and uniformity of crumb pore, softness, chewiness, overall acceptability, lotus leaf flavor, delicious taste, astringency, bitterness, and off-flavor were not significantly different among the samples. The results indicate that adding 0.02$\sim$ 0.03% hemicellulase in N elumbo nucifera G. tea white bread is optimal for quality and provides a product with reasonably high overall acceptability.

• Korean Journal of Poultry Science
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• v.43 no.4
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• pp.207-212
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• 2016

This work was carried out to investigate the ability of thirteen crossbreds for production of commercial chicken (CC) of Korean native chicken to be cut out for Korean circumstance. Total of one thousand three hundred of crossbreds were divided thirteen groups (100 birds/group) that were twelve groups (1A, 1B, 2A, 2B, 3A, 3B, 4A, 4B, 5A, 5B, 6A, 6B) to crossbreed with two sires (A, B) and six dams (1, 2, 3, 4, 5, 6) of parent stock (PS) of Korean native chicken and one group (HH) as commercial Korean native chicken. Experimental diets were starter diet (0~7d; CP 22.0% ME 3,150 kcal/kg), early diet (8d~Wt 800 g; CP 19.0% ME 3,150 kcal/kg) and finished diet (Wt 800 g~12 wk; CP 18.0% ME 3,150 kcal/kg). Fertility of 1B group was higher than other groups. Hatchability per fertilization eggs and hatchability per setting eggs were 87.5~89% and 87.9~96.3%, respectively, and those of 4B and 6B groups were lower compared to other groups. Weekly body weight of HH group was lower than other groups. CV values of body weight of thirteen groups were showed over 12% as 12.5~18.2%, and especially, those of 2B, 3B, 5B, HH groups were lower compared to other groups. Weekly feed conversion ratios (FCRs) of 13 crossbreds were 1.7~2.3, 2.1~2.5, 2.4~2.7 and 2.7~3.2 at the age of 6, 8, 10 and 12 weeks, respectively. Weekly production indexes of 2A, 3A and HH groups were the lower than other groups and those of thirteen groups decreased following weeks. Feed costs per body weight gain (kg) were 1,069~1,255 won, 1,100~1,263 won, and 1.468~1,696 won at starter, earlier and finished period of broilers. These results leaded down to conclusion to be possible selection of new Korean native commercial chicken that have the excellent performance and economics.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.1
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• pp.17-25
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• 2022

This study was carried out the estimation on consumption patterns and consciousness of domestic forage for improvement of the quality of domestic forage. Although the cultivated area in South Korea of forage has increased significantly compared to the past, the self-sufficiency rate of domestic forage has increased to around 80% since 2010. Also, livestock farmers prefer to use import forage than domestic due to convenience of use. In Korean beef farms, the ratio of import to domestic forage was higher in domestic forage (import forage 3 : domestic forage 7). In the method of securing domestic forage, purchase of forage (55.6%) was higher than self-cultivation of forage (44.4%). The ratio of use by bailing type was shown in the order of rice staw rice straw (50.5%), domestic hay (15%), imported hay (12.5%), and total mixed ratio (10.7%). The preference of forage was in the order of amount of foreign matter, moisture content, price, feed value in Korean native cattle farm. The result of satisfaction with domestic and import forage showed that the satisfaction of domestic forage price was higher than import forage, while the moisture content and foreign matter of forage were lower than import forage. In addition, in the results of the satisfaction and importance of domestic roughage compared to imported roughage, satisfaction with imported roughage was generally high in all items except for price. As a result, in order to improve the satisfaction of domestic forage in Korean native cattle farm, it is necessary to minimize foreign matter in forage and increase hay production for moisture content uniform in forage.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.3
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• pp.125-132
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• 2007

We estimated the distribution of predator-prey interaction strengths for 12 species of herbivores (including amphipods, isopods, gastropods, and sea urchins) and made a regression model that may be applicable to other species. Laboratory experiments were used to determine per capita grazing rate (PCGR; g seaweeds/individual/day). Relationship between the biomass of individual grazers and fourth-root transformed PCGR was fitted to power curve ($y=0.2310x^{0.3290}$, r=0.8864). This finding supported that the grazing efficiency was not even as individual grazers increase in size (biomass). Therefore, the biomass-normalized PCGR was estimated and revealed that smaller size herbivores were more effective grazers. Grazing impact considering density of each taxon was calculated. The sea hare Aplysia kurodai had greatest grazing impact on the seaweed bed and the sea urchin Strongylocentrotus nudus and S. intermedius were ranked in descending order of the impact. The amount of seaweed grazed by the amphipod Elasmopus sp. (>4,000 $ind./m^2$) and Jassa falcata (>2,000 $ind./m^2$) were 3.435 and $1.697mg/m^2/day$ respectively. The combined grazing amount of herbivores was $5,045mg/m^2/day$ in the seaweed bed. Although sea hare and sea urchin had strong impacts on seaweeds, the effects of dense, smaller species could not be seen as negligible. Surprisingly, the calculated grazing potential of sea urchins with a mean density of 3 $ind./m^2$ exceeded the mean production of seaweed cultured in domestic coastal waters in Korea (ca., 5 ton/ha). Small crustaceans were also expected to consume up to 16% of the seaweed production if their densities were rising under weak predation conditions. Considering that the population density of herbivores are strongly controlled by fish, human interference like overfishing may have strong negative effects on persistence of seaweeds communities.

• Radiation Oncology Journal
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• v.23 no.3
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• pp.143-156
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• 2005

Background: The best dose-fractionation regimen of the definitive radiotherapy for cervix cancer remains to be clearly determined. It seems to be partially attributed to the complexity of the affecting factors and the lack of detailed information on external and intra-cavitary fractionation. To find optimal practice guidelines, our experiences of the combination of external beam radiotherapy (EBRT) and high-dose-rate intracavitary brachytherapy (HDR-ICBT) were reviewed with detailed information of the various treatment parameters obtained from a large cohort of women treated homogeneously at a single institute. Materials and Methods: The subjects were 743 cervical cancer patients (Stage IB 198, IIA 77, IIB 364, IIIA 7, IIIB 89 and IVA 8) treated by radiotherapy alone, between 1990 and 1996. A total external beam radiotherapy (EBRT) dose of $23.4\~59.4$ Gy (Median 45.0) was delivered to the whole pelvis. High-dose-rate intracavitary brachytherapy (HDR-IBT) was also peformed using various fractionation schemes. A Midline block (MLB) was initiated after the delivery of $14.4\~43.2$ Gy (Median 36.0) of EBRT in 495 patients, while In the other 248 patients EBRT could not be used due to slow tumor regression or the huge initial bulk of tumor. The point A, actual bladder & rectal doses were individually assessed in all patients. The biologically effective dose (BED) to the tumor ($\alpha/\beta$=10) and late-responding tissues ($\alpha/\beta$=3) for both EBRT and HDR-ICBT were calculated. The total BED values to point A, the actual bladder and rectal reference points were the summation of the EBRT and HDR-ICBT. In addition to all the details on dose-fractionation, the other factors (i.e. the overall treatment time, physicians preference) that can affect the schedule of the definitive radiotherapy were also thoroughly analyzed. The association between MD-BED $Gy_3$ and the risk of complication was assessed using serial multiple logistic regression models. The associations between R-BED $Gy_3$ and rectal complications and between V-BED $Gy_3$ and bladder complications were assessed using multiple logistic regression models after adjustment for age, stage, tumor size and treatment duration. Serial Coxs proportional hazard regression models were used to estimate the relative risks of recurrence due to MD-BED $Gy_{10}$, and the treatment duration. Results: The overall complication rate for RTOG Grades $1\~4$ toxicities was $33.1\%$. The 5-year actuarial pelvic control rate for ail 743 patients was $83\%$. The midline cumulative BED dose, which is the sum of external midline BED and HDR-ICBT point A BED, ranged from 62.0 to 121.9 $Gy_{10}$ (median 93.0) for tumors and from 93.6 to 187.3 $Gy_3$ (median 137.6) for late responding tissues. The median cumulative values of actual rectal (R-BED $Gy_3$) and bladder Point BED (V-BED $Gy_3$) were 118.7 $Gy_3$ (range $48.8\~265.2$) and 126.1 $Gy_3$ (range: $54.9\~267.5$), respectively. MD-BED $Gy_3$ showed a good correlation with rectal (p=0.003), but not with bladder complications (p=0.095). R-BED $Gy_3$ had a very strong association (p=<0.0001), and was more predictive of rectal complications than A-BED $Gy_3$. B-BED $Gy_3$ also showed significance in the prediction of bladder complications in a trend test (p=0.0298). No statistically significant dose-response relationship for pelvic control was observed. The Sandwich and Continuous techniques, which differ according to when the ICR was inserted during the EBRT and due to the physicians preference, showed no differences in the local control and complication rates; there were also no differences in the 3 vs. 5 Gy fraction size of HDR-ICBT. Conclusion: The main reasons optimal dose-fractionation guidelines are not easily established is due to the absence of a dose-response relationship for tumor control as a result of the high-dose gradient of HDR-ICBT, individual differences In tumor responses to radiation therapy and the complexity of affecting factors. Therefore, in our opinion, there is a necessity for individualized tailored therapy, along with general guidelines, in the definitive radiation treatment for cervix cancer. This study also demonstrated the strong predictive value of actual rectal and bladder reference dosing therefore, vaginal gauze packing might be very Important. To maintain the BED dose to less than the threshold resulting in complication, early midline shielding, the HDR-ICBT total dose and fractional dose reduction should be considered.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.8
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• pp.1118-1133
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• 2012

This research aimed to suggest an efficient improvement plan for school food services by investigating the operating situation and recognition of menu management in school food services for school food service dietitians (and nutrition teachers) in Chungbuk. A total of 328 questionnaires were distributed to school food service dietitians (and nutrition teachers) in Chungbuk by e-mail in September, 2010. A total of 265 questionnaires (80.8%) were used for the analysis. The highest allocation of nutrients and calories per day in school food services was 1:1.5:1.5 (breakfast : lunch : dinner) (38.5%). The reasoning for applying a flexible allocation of nutrients and calories per day was 'considering the ratio of students who do not eat breakfast' (59.2%). And the way to apply the flexible allocation for nutrients and calories per day was 'by agreement from the school operating committee in arbitrary data without situation surveys' (86 respondents, 49.4%), and 'by agreement from the school operating committee in analysis data through situation surveys' (80 respondents, 46.0%). The operational method of standardized recipes was 'cooking management site of national education information systems' (87.5%) and the items included in standardized recipes were menu name, food material name, portion size, cooking method, nutrition analysis, and critical control point in HACCP. The main reason for not utilizing all items of a cooking management site of the national education information system was 'no big trouble in menu management even though it is used partly (29.1%). In addition, the highest use of standardized recipe was for 'maintaining consistency of food production quantity' (74.0%).

• Radiation Oncology Journal
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• v.21 no.3
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• pp.227-237
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• 2003

Purpose: The human chronic myelogenous leukemia cell line, K562, expresses the chimeric bcr-abl oncoprotein, whose deregulated protein tyrosine kinase activity antagonizes via DNA damaging agents. Previous experiments have shown that nanomolar concentrations of herbimycin A (HWA) coupled with X-irradiation have a synergistic effect in inducing apoptosis in the Ph-positive K562 leukemia cell line, but genistein, a PTK inhibitor, is non selective for the radiation-induced apoptosils on $p210^{bcr/abl}$ protected K562 cells. In these experiments, the cytoplasmic signal transduction pathways, the Induction on a number of transcription factors and the differential gene expression in this model were investigated. Materials and Methids: K562 cells in the exponential growth phase were used in this study. The cells were irradiated with 0.5-12 Gy, using a 6 Mev Linac (Clinac 1800, Varian, USA). Immediately after irradiation, the cells were treated with $0.25/muM$ of HMA and $25/muM$ of genistein, and the expressions and the activities of abl kinase, MAPK family, NF- kB, c-fos, c-myc, and thymidine kinase1 (TK1) were examined. The differential gene expressions induced by PTK inhibitors were also investigated. Results: The modulating effects of herbimycin A and genistein on the radiosensitivity of K562 cells were not related to the bcr-abl kinase activity. The signaling responses through the MAPK family of proteins, were not involved either in association with the radiation-induced apoptosis, which is accelerated by HMA, the expression of c-myc was increased. The combined treatment of genistein, with irradiation, enhanced NF- kB activity and the TK1 expression and activity. Conclusion: The effects of HMA and genistein on the radiosensitivity on the K562 cells were not related to the bcr-abl kinase activity in this study, another signaling pathway, besides the WAPK family responses to radiation to K562 cells, was found. Further evaluation using this model will provide valuable information for the optional radiosensitization or radioprotection.