• Journal of the Korean Geosynthetics Society
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• v.10 no.1
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• pp.37-42
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• 2011

In this study, it is analyzed that mechanical properties and required strength of porous concrete according to the mixing ratio of cement, fine aggregate, and water/cement ratio in order to evaluate mechanical properties of porous concrete using recycled asphalt aggregate. Recycled asphalt aggregates of 13 mm were used without modification of aggregate grading to extend porous concrete application. The water/concrete ratio was poor mix and the range of compressive strength was 18.2 to 19.5 MPa. The average value of permeability showed 8.0E-02 cm/sec.

• Wind and Structures
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• v.18 no.1
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• pp.83-101
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• 2014

Lamps installed on stay cables of cable-stayed bridges may alter the configuration of circular cross section of the cables and therefore result in aerodynamically unstable cable vibrations. The background of this study is a preliminary design of lamp installation on the cable-stayed He-dong Bridge in Guangzhou, China. Force measurements and dynamic response measurements wind tunnel tests were carried out to validate the possibility of cable galloping vibrations. It is observed that galloping will occur and the critical wind velocity is far less than the design wind velocity at Guangzhou City stipulated in Chinese Code. Numerical simulations utilizing software ANSYS CFX were subsequently performed and almost the same results as the wind tunnel tests were obtained. Moreover, the pressure and velocity contours around cable-lamp model obtained from numerical simulations indicated that the upstream steel wire in the preliminary design is the key factor for the onset of the galloping vibrations. A modification for the preliminary design of lamp installation, which suggests to remove the two parallel steel wires, is proposed, and it effectiveness is validated in further wind tunnel tests.

• Journal of Ecology and Environment
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• v.33 no.2
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• pp.121-131
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• 2010

Betula platyphylla var. japonica and Betula ermanii segregate vertically at an elevation of approximately 1,850 m on Mt. Neko in Nagano Prefecture, Japan. B. platyphylla var. japonica and B. ermanii were the dominant species below and above this altitude, at which the mean-annual and growing-season air temperatures were $4^{\circ}C$ and $14.1^{\circ}C$, respectively. Based on a modification of Kira's warmth index which employs cumulative temperature represented as $^{\circ}C$ day, leaf unfolding in both species was observed to be initiated at $58^{\circ}C$ day and $169^{\circ}C$ day, respectively. In 1996, leaf unfolding was initiated on 18 May in B. platyphylla var. japonica (+/-6 days) and on 5 June in B. ermanii (+/-8 days), shortly after the last frost which occurred on 5 May 1995 above 1,850 m; below this elevation there was no risk of frost at the time. At elevations above 1,850 m, the unfolded leaves of B. platyphylla were damaged by late frost, while B. ermanii escaped injury because the leaves were still protected by winter buds. The optimum temperature for seed germination in both B. platyphylla and B. ermanii was $30^{\circ}C$. Temperature alternation from 10 to $30^{\circ}C$ and moist storage of seeds at $4^{\circ}C$ (stratification) prior to incubation increased germination rates in both species. The seedlings of B. ermanii had a greater survival rates than those of B. platyphylla var. japonica when planted above 1,850 m. Comparisons of the timing of leaf unfolding and the latest frost at a site appeared to be the main factors affecting the vertical distribution of these species.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.12
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• pp.1684-1690
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• 2005

Using mRNA differential display technique, we investigated differential gene expression in hybrids relative to their parents in a diallel cross involving four chicken breeds in order to provide an insight into the molecular basis of heterosis in chicken. The results indicated that there was extensive differential gene expression between chicken F1 hybrids and their parents which was classified into four kinds of patterns as following: (1) bands only detected in hybrid F1; (2) bands only absent in hybrid F1; (3) bands only detected in parent P1 or P2; (4) bands absent in parent P1 or P2. Forty-two differentially expressed cDNAs were cloned and sequenced, and their expression patterns were confirmed by Reverse-Northern dot blot. Sequence analysis and database searches revealed that genes showed differential expression between hybrid and parents were regulatory and functional genes involved in metabolism, mRNA splicing, transcriptional regulation, cell cycles and protein modification. These results indicated that hybridization between two parents can cause changes in expression of a variety of genes. In conclusion, that the altered pattern of gene expression in hybrids may be responsible for heterosis in chickens.

• Applied Microscopy
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• v.42 no.1
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• pp.43-48
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• 2012

This study shows that ceresin wax, candellila wax and microcrystalline wax mixed together with liquid paraffin oil to produce lipsticks (LS-1, LS-2) and capric/caprylic triglyceride oil added to produce lipsticks (LS-3, LS-4). After each type of lipsticks were molded, LS-1 and LS-3 was put into a cooling chamber ($5^{\circ}C$). LS-2 and LS-4 was put into a cooling chamber ($5^{\circ}C$) for 18 hours and kept in an incubator ($45^{\circ}C$) for 5 hours and put again into a cool chamber ($5^{\circ}C$). After that, the wax's three dimensional network structure was observed under scanning electron microscopy. Regardless of the kind of oil, the LS-1 and LS-3 wax structure had more distinct shape than the lipstick wax structure of LS-2 and LS-4. Also, regardless of the kind of wax, the three dimensional network structure was modified as the storage temperature increased. As a result, the lipstick's molding temperature increased, the wax's structure size also increased and the shape irregularly modified. This modification causes sweating phenomenon which affected lipstick's surface rheological property.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.60-60
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• 2000

The adhesion interface formation between copper and poly(ethylene terephthalate)(PET), poly(methyl methacrylate)(PMMA) and Polyimide films was treated using Ion assisted reaction system to sequential sputter deposition by High-Frequency ion source. The ion beam modification system used a new type of low power HF ion thruster for space application as new low thruster electric propulsion system. Low power HF ion thruster with diameter 100mm gives the opportunity to obtain beams of Ar+ with currents 20~150 mA (current density 0.5~3.5 mA/cm2) and energy 200~2500eV at HF power level 10~150 W. Using Ar as a working gas it is possible to obtain thrust within 3~8 mN. Contact angles for untreated films were over 95$^{\circ}$ and 80 for Pet, 10o for PMMA and 12o for PI samples as a condition of ion assisted reaction at the ion dose of 10$\times$1016 ions/cm2, the ion beam potential of 1.2 keV and 4 ml/min for environmental gas flow rate. 900o peel tests yielded values of 15 to 35 for PET, 18 to 40 and 12 to 36 g/min. respectively. High resolution X-ray photoelectron spectrocopy is the Cls region for Cu metal on these polymer substrates showed increases in C=O-O groups for polymide, whereas PET and PMMA treated samples showed only C=O groups with increase the ion dose. Finally, unstable polymer surface can be changed from hydrophobic to hydrophilic formation such as C-O and C=O that were confirmed by the XPS analysis, conclusionally, the ion assisted reaction is very effective tools to attach reactive ion species to form functional groups on C-C bond chains of PET, PMMA and PI.

• Journal of Biosystems Engineering
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• v.8 no.2
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• pp.18-25
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• 1983

The binders introduced in Korea were originally designed to be used for Japonica varieties which have realtively long stem and are highly resistant to shattering. In order to use it for Tongil varieties which are short and easy to be shattered, mechanical modifications are necessary to reduce a grain loss incurred during its operation. This study was intended to investigate the binding unit, one of the major factors affecting grain losses. The binding parts of three binders used in Korea were analyzed and the grain loss was experimentally assessed for these binders. The results obtained from this study are summarized as follows: 1. From the motion analysis of discharge mechanism, the trajectory of the discharge arm appeared to be either circular or skewed elliptic. The velocity of a circular path mechanism was constant and smaller than that of a skewed elliptic path mechanism. The discharge grain loss of the former was about twice less than that of the latter. 2. It was found that the grain loss incurred due to the collision of the paddy bundles and ground was considerably high for Tongil varieties. The auxiliary discharge bar gave a significant influence on the motion and posture of the bundles, and the degree of impact on ground. 3. The installation of an auxiliary bar, which guides the paddy bundles smoothly to ground in order to reduce impact when the bundles fall down on ground, appeared to be very effective since the grain losses could be decreased by about 1.6 percentage point. However, the guide bar should be installed after some mechanical modification to reduce the velocity of discharge arm has been made.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.629-632
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• 2009

The polymeric desiccant rotor is made from the super absorbent polymer by ion modification. The moisture sorption capacity of the super desiccant polymer(SDP) is 4 to 5 times larger than those of common desiccant meterials such as silica gel or zeolite. It is also known that SDP can be regenerated even at the relatively low temperature. To fabricate the desiccant rotor, firstly the SDP was laminated by coating the SDP on polyethylene sheet. Then corrugated and rolled up into a rotor. The diameter, the depth, the dimensions of the corrugated channel, etc. were pre-determined from numerical simulation on the heat and mass transfer in the desiccant rotor. The dehumidification performance was tested in a climate chamber. The relevant tests were carried out at the process air inlet temperature of $32^{\circ}C$, the regeneration air inlet temperature of $60^{\circ}C$ and the inlet dew-point temperature of both the process air and the regeneration air of $18.5^{\circ}C$, when the rotation period is long, the moisture sorption is not effective. In the desiccant rotor developed in this study, the optimum rotation period is found about 350s at the regeneration temperature of $60^{\circ}C$. It was found from further experiments that the optimum rotation tends to decreases as the regeneration temperature increases. Meanwhile, the outlet temperature of the process air deceases monotonically as the rotation period increases.

• ALGAE
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• v.34 no.2
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• pp.153-162
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• 2019

Anthropogenic disturbances, including coastal habitat modification and climate change are threatening the stability of kelp beds, one of the most diverse and productive marine ecosystems. To test the effect of temperature and irradiance on the microscopic gametophyte and juvenile sporophyte stages of the rare kelp, Saccharina angustissima, from Casco Bay, Maine, USA, we carried out two sets of experiments using a temperature gradient table. The first set of experiments combined temperatures between $7-18^{\circ}C$ with irradiance at 20, 40, and $80{\mu}mol\;photons\;m^{-2}\;s^{-1}$. The second set combined temperatures of $3-13^{\circ}C$ with irradiance of 10, 100, and $200{\mu}mol\;photons\;m^{-2}\;s^{-1}$. Over two separate 4-week trials, in 2014 and again in 2015, we monitored gametogenesis, the early growth stages of the gametophytes, and early sporophyte development of this kelp. Gametophytes grew best at temperatures of $8-13^{\circ}C$ at the lowest irradiance of $10-{\mu}mol\;photons\;m^{-2}\;s^{-1}$. Light had a significant effect on both male and female gametophyte growth only at the higher temperatures. Temperatures of $8-15^{\circ}C$ and irradiance levels of $10-100{\mu}mol\;photons\;m^{-2}\;s^{-1}$ were conditions for the highest sporophyte growth. Sporophyte and male gametophyte growth was reduced at both temperature extremes-the hottest and coldest temperatures tested. S. angustissima is a unique kelp species known only from a very narrow geographic region along the coast of Maine, USA. The coupling of global warming with high light intensity effects might pose stress on the early life-history stages of this kelp, although, as an intertidal species, it could also be better adapted to temperature and light extremes than its subtidal counterpart, Saccharina latissima.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.3
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• pp.61-66
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• 2009

Purpose: Glomerular filtration rate (GFR) is considered as the best overall index for the level of renal function, diagnosis of doubtful kidney disease, progress observation from chronic kidney disease and is measured with the various methods. In this study, We measured standard GFR by Gates method and attempted to compare the result with serum creatinin-based, Cockcroft-Gault(C-G) formula and Modification of Diet in Renal Disease (MDRD) formula. Materials and methods: 217 patients (127 men, 90 women, mean age $51.3{\pm}16.9$) with various renal function were examined. we compared the GFR using $^{99m}Tc$-DTPA (Gates), C-G formula and MDRD formula. Results: Significant correlations were noted between 2 different GFR estimates (from C-G formula: r=0.864, p<0.0001, MDRD formula: r=0.831, p<0.0001) and $^{99m}Tc$-DTPA (Gates) GFR. Average of serum creatinine (Scr) was measured with $3.0{\pm}3.1\;mg/dL$, In patients with normal renal function (Scr<1.5 mg/dL), $^{99m}Tc$-DTPA (Gates) GFR was statistically significant to C-G formula (p<0.0001) and MDRD formula (p<0.0001). In patients with mild to moderate renal insufficiency (1.5$^{99m}Tc$-DTPA (Gates) GFR was not statistically significant to C-G formula (p=0.181) and MDRD formula (p=0.127). In patients with severe renal insufficiency (Scr>4.0mg/dL), $^{99m}Tc$-DTPA (Gates) GFR was statistically significant to C-G formula and MDRD formula (p<0.0001). Conclusions: Glomerular filtration rate using Gates method was closly correlated to C-G formula and MDRD formula. In patients with normal renal function, $^{99m}Tc$-DTPA (Gates) GFR was significantly lower than C-G formula and MDRD formula. In patients with mild to moderate renal insufficiency, $^{99m}Tc$-DTPA (Gates) GFR was simmilar with C-G formula and MDRD formula. In patients with severe renal insufficiency, $^{99m}Tc$-DTPA (Gates) GFR was significantly higher than C-G formula and MDRD formula. None of the three different methods was clearly superior to the others.