• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.41 no.5
• /
• pp.37-42
• /
• 2004

Shallow $p^{＋}$-n junctions were formed by preamorphization, low-energy ion implantation and dual-step annealing processes. Germanium ions were implanted into silicon substrates for preamorphization. The dopant implantation was performed into the preamorphized and non-preamorphized substrates using B $F_2$2 ions. Rapid thermal anneal (RTA) and furnace anneal (FA) were employed for dopant activation and damage removal. Samples were annealed by one of the following four methods; RTA(75$0^{\circ}C$/10s)＋Ft FA＋RTA(75$0^{\circ}C$/10s), RTA(100$0^{\circ}C$/10s)＋FA, FA＋The Ge Preamorphized sample exhibited a shallower junction depth than the non-preamorphized sample. When the employed RTA temperature was 100$0^{\circ}C$, FA＋RTA annealing sequence exhibited better junction characteristics than RTA＋FA thermal cycle from the viewpoint of junction depth, sheet resistance, $R_{s}$$.$ $x_{j}$, and leakage current.t.

• Korean Journal of Community Nutrition
• /
• v.3 no.2
• /
• pp.174-189
• /
• 1998

The purpose of this study was to evaluate the nutritional status and growth of Korean infants, who were atending peripheral community clinics in low income areas, by anthropometric measurements and estimating dietary intakes. Dietary intakes and growth were compared among different feeding patterns of 143 infants until age 9 months. The overall mean nutrient intakes of infants in this study were below the recommended allowances except the calcium intake from significant difference in each groups; however, calcium, zinc and iron intake of the formula fed infant(FF) was higher than the breast fed infant(BF) or the mixed fed infant(MF). Form ages 4-6 months, the nutrient intakes were shown to be higher in groups that were given supplementary foods than groups that were not. From ages 7-9 months, all nutrient intakes were higher in or the formula and supplementary foods fed(ESF) infants than in the breast and supplementary food(BSF) or the formula and supplementary food(FSF) groups, All subjets in this study showed a large Z-score. The growth of infants up to 6 months of age showed no significant difference in the feeding pattern, however, after 7 months of age the BSF group had significantly lower weight than the FSF or the ESF groups, There were significant positive relationships between infants weight gain at age 7-9 months from birth and the current protein or zinc intakes. As a result the average status of nutrient intakes of infants in this area was loser than the RDA, however, the growth pattern was fairly good. Although the breast milk is beneficial for infants, mothers should be educated for the importance of supplemental food and its practice to support good mutrition(Korean J Community Nutrition 3 (2) : 174-189, 1998)

• Journal of Korean Society for Atmospheric Environment
• /
• v.23 no.2
• /
• pp.183-190
• /
• 2007

In this study, we have investigated waste incinerators which are one of the major HAPs emission sources. In order to obtain more reliable HAPs emission data from waste incinerators, direct sampling for the possible pollutants from the stack was carried out and the analysis was performed. The purpose of study was to understand the emission status from waste incinerators and recognize the problems and finally to set up a strategy to reduce the HAPs emissions from waste incinerators. The emission concentrations of 8 species of heavy metals and 16 species of PAHs have been analyzed for the first time in Korea. Not only the emission characteristics of HAPs from waste incinerators were identified, but also the analysis of reduction efficiencies for control devices such as BF and wet scrubbing systems was carried out.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.21 no.2
• /
• pp.111-118
• /
• 2017

In this paper, combustion tests were performed to investigate performance characteristics of a canted slit-type pintle injector engine which uses kerosene and liquid oxygen as propellants. The number of slits, slit angle and blockage factor were chosen as design variables of the pintle injector. ${\Delta}SR$ was newly defined as the difference of skip ratio caused by both sides of the tip of the canted slit. The experimental results showed that optimal combustion was performed when the blockage factor is about 1 and the difference is less than 0.26.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.24 no.2
• /
• pp.68-77
• /
• 2020

The purpose of the paper is to evaluate the pore structure and mechanical properties of early frost damaged concrete using electric arc furnace slag as aggregate. From the results, when the concrete is exposed to frost damage at an early age, the peak point of pores 100 to 150 ㎛ in diameter were transferred into larger one. When the freezing duration is not exceeded 24 hours, it is possible that the pore distribution of under the 200 ㎛ is maintained and pore size of over 500 ㎛ is not formed, and, the freezing resistance of concrete using EFG could be improved. When BFS was mixed in concrete using EFG as coarse aggregate, the relative strength is higher than that of natural coarse aggregate. Meanwhile, the elastic modulus and resonance frequency did not change significantly due to the early frost damage as compared with the compressive strength. So, it is necessary to analyze the correlation between the experimental results in order to evaluate the performance degradation due to early frost damage.

• Asian-Australasian Journal of Animal Sciences
• /
• v.18 no.4
• /
• pp.458-462
• /
• 2005

The study was aimed at detecting polymorphism of the fifth intron in lipoprotein lipase (LPL) gene and analyzing association between the polymorphism and productive traits. A pair of primers was designed for amplifying the fifth intron. Sequence analysis indicated that a G1171C substitution existed in Large White breed. The mutation was detected by PCR-AfaI-RFLP. Polymorphism analysis in a pig resource family showed that there existed significant effects on carcass and meat quality traits. Thoraxwaist fat thickness of BB genotype was significantly higher (14.2%, p<0.05) than that of AA on carcass traits, while BB genotype was significantly lower (3.6% p<0.01, 4.1% p<0.01; 2.3% p<0.01, 1.9% p<0.01; 1.8% p<0.01, 1.4% p<0.05) than AA and AB genotype in pH of m. Longissimus Dorsi (LD), m. Biceps Femoris (BF), m. Semipinali Capitis (SC). The allelic frequencies were also significantly different between indigenous Chinese breeds and exotic breeds. Data analyzed revealed that the mutation locus affected production traits mostly by additive effects. Based on these results, it is necessary to do more studies on LPL gene before making the LPL locus into the application of marker-assisted selection (MAS) programs.

• Parasites, Hosts and Diseases
• /
• v.35 no.3
• /
• pp.181-188
• /
• 1997

In order to clarify the effect of cryptosporidiosis on immune response, histopathological changes associated with experimentally occurring bursal cryptosporidiosis in chickens were chronologically observed as the first step. A total of 150 2-day-old chickens was each inoculated orally with a single dose of 5 × 105 Cryptospori,mum bailevi oocysts. The chickens showed a normal profile of oocyst shedding in droppings. The bursa indices throughout the experimental period indicated negligible reactions. Numerous cryptosporidia occurred in the microvillous border of bursal epithelium between days 4 and 16 postinoculation (PI). Appearance of the most mast cells was followed by a dramatic loss of the protozoa in the bursa of Fabricius (BF). The distribution of the coccidium coincided with heterophil infiltration in the epithelium and adjacent lamina propria. The histopathological lesion was marked diffuse chronic superficial purulent bursitis with heterophil infiltration in the epithelium and adjacent lamina proprla and mucosal epithelial hyperplasia. These results suggest that the bursitis may induce immunosuppressive effect.

• Korean Journal of Applied Biomechanics
• /
• v.19 no.2
• /
• pp.257-264
• /
• 2009

The purpose of this study was to investigate the lower extremity kinematics and muscle activities of adductor longus(AL), gluteus medius(GME), gluteus maximus(GMA), biceps femoris(BF), rectus femoris(RF), gastrocnemius(GA), and tibialis anterior(TA) using three dimensional and Noraxon 8 channels EMG system during turn 0, 60, 90 and 120 degrees in patients with Parkinson's disease. Seven parkinson's patients and five healthy subjects were participated in the study. Participants with Parkinson's disease demonstrated significant differences in reduction of stride length and stride width. Also, they showed ill difference in muscle activities. The strength and balance of the lower extremity muscles may help to improve cutting movement and to prevent falling in parkinson's patients.

• Proceedings of the Ginseng society Conference
• /
• 1998.06a
• /
• pp.224-230
• /
• 1998

This study showed the anti-invasive activity of ginseng components, panaxadiol (PD) and panamatrlol (PT) on the highly metastatic HT1080 human flbrosarcoma cell line. PD and PT reduced tumor cell invasion through a reconstitute basement membrane in the transwell chamber. A significant down regulation of MMP-9 by PD and PT was detected by northern blot analysis. However, MMP-2 was constantly expressed. Quantitative gelatin based zymography confirmed a marked reduced expression of MMP-9 but not MMP-2 in the treatment of PD and PT. Since the chemical structures of PD and PT are very similar to that of dexamethasone, a synthetic glucocorticoid, it was investigated whether PD and PT act through GR. Western blot analysis and immunocytochemistry showed that PD and PT increased the GR fraction in the nucleus. These results suggest that ursolic acid may induce repression of MMP-9 by stimulating the nuclear translocation of GR and hence inhibiting the activity of AP-1 to TPA-responsible element of MMP-9 promoter region. In conclusion, we suggest that CR-induced down-regulation of MMP-9 by PD and PT contributes to reduce the invasive capacity of HT 1080 cells.

• Journal of the Korea Concrete Institute
• /
• v.23 no.6
• /
• pp.741-747
• /
• 2011

In this study, autogenous shrinkage strain and prediction models of concrete specimens were compared with strength level and development rate. Also, concrete autogeneous shrinkage under various curing conditions was investigated. The results showed that autogeneous shrinkage increased as concrete strength increased. However, when the concrete strength was almost identical, the initial autogeneous shrinkage of OPC was larger than BFS, but the final autogeneous shrinkage of BFS was larger than OPC. Early wet curing reduced autogeneous shrinkage strain. Especially, when the early wet curing was applied for more than 24 hours, final autogeneous shrinkage was significantly reduced. The results showed that the existing EC2 models do not reflect concrete properties properly. Therefore, the revised model was proposed to better predict autogeneous shrinkage.