• Asian-Australasian Journal of Animal Sciences
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• v.27 no.8
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• pp.1131-1140
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• 2014

This research focused on the effects of different doses of Bacillus subtilis KN-42 on the growth performance, diarrhea incidence, faecal bacterial flora, and the relative number of Lactobacillus and Escherichia coli in faeces of weaned piglets to determine whether the strain can serve as a candidate antimicrobial growth promoter. A total of 360 piglets (initial body weight $7.14{\pm}0.63$ kg) weaned at $26{\pm}2$ days of age were randomly allotted to 5 treatment groups (4 pens per treatment with 18 pigs per pen) for a 28-day trial. Dietary treatments were basal diet without any antimicrobial (negative control; NC), basal diet supplemented with 120 mg/kg feed of neomycin sulfate (positive control; PC) and basal diet supplemented with $2{\times}10^9$ (L), $4{\times}10^9$ (M) and $20{\times}10^9$ (H) CFU/kg feed of B. subtilis KN-42. During the overall period, average daily gain and feed efficiency of piglets were higher in groups PC, M, and H than those in group NC (p<0.05), and all probiotics and antibiotics groups had a lower diarrhea index than group NC (p<0.05). The 16S rDNA gene-based methods were used to analyze faecal bacterial flora on day 28 of experiment. The result of denaturing gradient gel electrophoresis analysis showed that supplementation of B. subtilis KN-42 to the diet changed the bacterial communities, with a higher bacterial diversity and band number in group M than in the other four groups. Real-time polymerase chain reaction analysis showed that the relative number of Lactobacillus were higher in groups PC and H than in group NC (p<0.05), and the supplemented B. subtilis KN-42 to the diet also reduced the relative number of E. coli (p<0.05). These results suggest that dietary addition of B. subtilis KN-42 can improve the growth performance and gastrointestinal health of piglets.

• Journal of Korean Society on Water Environment
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• v.28 no.1
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• pp.63-70
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• 2012

This study was carried out to investigate change in influent concentration of domestic wastewater flowed from a newly constructed separate sewer system (SSS) and biological nutrients removal efficiency of a full scale Air-vent sequential batch reactor (SBR, $600m^3/d$). The average concentration of $BOD_5$, SS, T-N and T-P from SSS were 246.5 mg/L, 231.6 mg/L, 42.974 mg/L, 5.360 mg/L, respectively which corresponds to 2.2times, 1.2times, 1.8times and 2.1times higher than those from the conventional combined sewer system (CSS). The removal efficiency of $BOD_5$, SS, T-N, and T-P for the Air-vent SBR operated with influent from SSS averaged 99.1%, 99.0%, 91.2%, and 93.5%, respectively. Especially the respective nitrogen and phosphorus removal was 15% greater than that of the SBR operated with influent from CSS. Simultaneous nitrification and denitrification (SND) was observed in an aerobic reactor(II) as a result of DO concentration gradient developed along the depth by the Air-vent system. In order to achieve T-N removal greater than 90%, the C/N ratio should be over 6.0 and the difference between $BOD_5$ loading and nitrogen loading rate be over 100 kg/day (0.130 kg $T-N/m^3{\cdot}d$). Even with high influent T-P concentration of 5.360 mg/L from SSS (compared with 2.465 mg/L from CSS) T-P removal achieved 93.5% which was 15.5% higher than that of the SBR with influent from CSS. This is probably due to high influent $BOD_5$ concentration from SSS that could provide soluble carbon source to release phosphorus at anaerobic condition. In order to achieve T-P removal greater than 90%, the difference between $BOD_5$ loading and phosphorus loading rate should be over 100 kg /day (0.130 kg $T-N/m^3{\cdot}d$).

• Journal of Korea Water Resources Association
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• v.33 no.2
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• pp.229-235
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• 2000

Characteristics of hail occurred during 1989-1998 is studied. Hail is observed mainly at west coast, southwest inland, and Taegwallyong. Average diameter of hailstone is 0.6 cm, and 70% of the occurrence frequency of hail is observed at west coast. During winter and spring, the wet -bulb zero height (WBZ) is low enough to prevent the melting process of hail. But the lack of available low-level moisture (mean mixing ratio in lowest 100 hPa) makes the size of hail small. As a result, smaller size hail is observed frequently over west coast. On the contrary, WBZ is higher during summer, it means that hail is melted before it reaches ground, but the size of hail is bigger. Thus the larger hail is observed mainly Taegwallyong during summer. Hail is observed from 1100 LST to 1500 LST over west coast and around 1800 LST over Taegwallyong. It suggest that thermally driven mesoscale circulations such as land-sea breeze and mountain ridge-valley circulation aid in the formation of hail. Upper and surface air temperature is related to formation of hailstorm. Before formation of hailstorm in November 1998, the upper air temperature decreases. And hails is observed in the spot of strong temperature and dew point temperature gradient coincidently.

• Korean Journal of Digital Imaging in Medicine
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• v.12 no.1
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• pp.27-31
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• 2010

The purpose of this study was to investigated the usefulness of MR perfusion image comparing with SPECT image. A total of pediatric 30 patients(average age : 7.8) with Moyamoya disease were performed MR Perfusion with 32 channel body coil at 3T from March 01, 2010 to June 10, 2010. The MRI sequences and parameters were as followed : gradient Echo-planar imaging(EPI), TR/TE : 2000ms/50ms, FA : $90^{\circ}$, FOV : $240{\times}240$, Matrix : $128{\times}128$, Thickness : 5mm, Gap : 1.5mm. Images were obtained contrast agent administrated at a rate of 1mL/sec after scan start 10s with a total of slice 1000 images(50 phase/1 slice). It was measured with visual color image and digitize data using MRDx software(IDL version 6.2) and also, it was compared of measurement with values of normal and abnormal ratio to analyze hemodynamic change, and a comparison between perfusion MR with technique using Warm Color at SPECT examination. On MR perfusion examination, the color images from abnormal region to the red collar with rCBV(relative cerebral blood volume) and rCBF(relative cerebral blood flow) caused by increase cerebral blood flow with brain vascular occlusion in surrounding collateral circulation advancement, the blood speed relatively was depicted slowly with blue in MTT(Mean Transit Time) and TTP(Time to Peak) images. The region which was visible abnormally from MR perfusion examination visually were detected as comparison with the same SPECT examination region, would be able to confirm the identical results in MMD(Moyamoya disease)judgments. Hymo-dynamic change in MR perfusion examination produced by increase and delay cerebral blood flow. This change with digitize data and being color imaging makes enable to distinguish between normal and abnormal area. Relatively, MR perfusion examination compared with SPECT examination could bring an excellent image with spatial resolution without radiation expose.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.2
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• pp.45-55
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• 2020

In terms of environmental justice, urban parks play a pivotal role in imperative amenities allowing for physical activity. The reasonable distribution of urban park services must be considered in terms of community demand and the context of the park. The purpose of this study is to analyze the inequity of qualitative park service according to the socioeconomic status(SES) in Daegu. The qualitative service was assessed for 82 neighborhood and walking-distance parks by utilizing the NGST(Neighborhood Green Space Tool). The inequity was analyzed by SES variables(ratio of basic living recipients, ratio of single-parent families, average housing sales, dilapidated dwelling ratio, and park area per capita). The features of the qualitative equity in Daegu is as follows. First, urban park planning in Daegu is in parallel with the development of residential areas rather than the local policy. The development pattern of parks stretching from center of the city to outskirts clearly dissociates the city based on socioeconomic status. The parks in the center are relatively old and poorly managed. Second, overall neighborhood parks lacked recreational facilities. The facilities are significantly influenced by the housing values around them. The lower the recreation facility score, the higher the floor gradient of the urban parks constraining physical activities. Third, the quantitative supply of parks has nothing to do with the quality of the urban parks. Green space distribution is highly dependent on natural park areas, so the park area per capita cannot be a standard for assessing qualitative equity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.1-11
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• 2020

This study investigated the mesozooplankton community and the related environmental factors in the Nakdong River Estuary in May and early October shortly after passage of the typhoon "DUJUAN" in 2015. The mesozooplankton community was dominated by barnacle nauplii, foraminiferans, and Noctiluca scintillans, and the environmental characteristics were characterized by freshwater inflow through the Nakdong River barrage, the intrusion of warm currents, and the effect of typhoon passage in October. In May, cladocerans, such as Evadne nordmanni and Podon polyphemoides, as indicator species of brackish water, prevailed throughout the study area. The surface salinity was lowest on the inner side of the barrier-islands and increased gradually to the outer side during the study. The average concentration of total suspended solids in October was higher than that in May, while the averaged concentration of nitrate and chlorophyll-a in May was higher than those in October. On the other hand, there was no temporal difference in the total averaged abundance of mesozooplankton. In contrast, the distributional pattern of the mesozooplankton community was associated with the salinity gradient in both seasons. These results suggest that the temporal difference of the mesozooplankton community depended on the extent of freshwater inflow by barrage opening, the intrusion intensity of warm currents, and typhoon passage in the Nakdong River estuary in 2015.

• Nutritional Sciences
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• v.1 no.1
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• pp.61-69
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• 1998

Five hundred and seventy-eight healthy subjects (351 men and 227 women) with a mean age of 44.8 years (45.2 for men, 44.3 for women) participated in this study. The serum concentrations of $\alpha$-tocopherol, \beta$-carotene, $\alpha$-carotene, zeaxanthin + lutein, cryptoxanthin, lycopene and retinol of normal Koreans were measured, and their relation to gender, age, BMI, alcohol consumption, cigarette smoking, and menopausal status were evaluated. The concentrations of $\alpha$-tocopherol, carotenoids and retinol in serum were measured simultaneously by reverse phase HPLC (multi-wavelength, gradient and computerized automatic system). Average serum levels of $\alpha$-tocopherol, \beta$-carotene and retinol were 10.1$\pm$0.41\mu$g/dl, 33.1$\pm$1.24\mu$g/dl, and 82.0$\pm$1.63\mu$g/dl for men and 11.1$\pm$0.74\mu$g/ml, 48.1$\pm$1.60\mu$g/dl and 64.5$\pm$1.96\mu$g/dl for women, respectively, Serum concentrations of $\alpha$-tocopheol \beta$-carotene, $\alpha$-carotene, cryptoxanthin and lycopene appeared to be higher in women than in men. The serum concentrations of zeaxanthin + lutein increased with the increase in age of men and those of $\alpha$-carotene and \beta$-carotene increased with the increase in age of women. For men, current smokers showed significantly lower serum concentrations of \beta$-carotene and $\alpha$-carotene than ex-smokers (p <0.05) . Current drinkers also showed significantly lower serum \beta$-carotene and zeaxanthin + lutein concentrations than ex-drinkers. For women, current smokers showed significantly love. serum concentrations of zeaxanthin+lutein and cryptoxanthin than ex-smokes (p<0.05). Men with BMI$\geq$24 showed significantly lower serum concentrations of \beta$-carotene, $\alpha$-carotene, lycopene and cryptoxanthin than men with BMI < 20. The mean concentrations of $\alpha$-tocopherol, \beta$-carotene, $\alpha$-carotene and lycopene far postmenopausal women were higher than those for premenopausal women (p<0.05). In conclusion, there were obvious differences in serum $\alpha$-tocopherol and carotenoids levels depending on gender, age, cigarette-smoking habits, alcohol consumption, BMI and menopausal status. further studies are required to establish the normal levels of these vitamins for children and the elderly and to elucidate their roles in different disease states.

• Journal of the Korea Society of Computer and Information
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• v.18 no.7
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• pp.23-35
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• 2013

This paper proposes an effective technique that is used to automatically extract feature vectors from vibration signals for fault classification systems. Conventional mel-frequency cepstral coefficients (MFCCs) are sensitive to noise of vibration signals, degrading classification accuracy. To solve this problem, this paper proposes spectral envelope cepstral coefficients (SECC) analysis, where a 4-step filter bank based on spectral envelopes of vibration signals is used: (1) a linear predictive coding (LPC) algorithm is used to specify spectral envelopes of all faulty vibration signals, (2) all envelopes are averaged to get general spectral shape, (3) a gradient descent method is used to find extremes of the average envelope and its frequencies, (4) a non-overlapped filter is used to have centers calculated from distances between valley frequencies of the envelope. This 4-step filter bank is then used in cepstral coefficients computation to extract feature vectors. Finally, a multi-layer support vector machine (MLSVM) with various sigma values uses these special parameters to identify faulty types of induction motors. Experimental results indicate that the proposed extraction method outperforms other feature extraction algorithms, yielding more than about 99.65% of classification accuracy.

• Journal of Technologic Dentistry
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• v.29 no.1
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• pp.121-131
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• 2007

A preparation process's conditions of aqueous sol which contains anatase-type nano titania particles with photocatalyic properties was established by using Yoldas process, so called, DCS(Destabilization of Colloidal Solution) process in this study. And crystal size change and phase transformation of titania particles in aqueous titania sol depending on reaction conditions was investigated by a light scattering method and XRD analysis of frozen dried powders, respectively. This sol with photo catalytic nano titania particles was used to the following hydrophilic hybrid coating film's fabrication and its properties was evaluated. Subsequently, for coating film using the above mentioned aqueous titania sol, non-aqueous titania sol was prepared without any chemical additives and its time stability according to aging time was investigate. By using the above mentioned aqueous titania sol and non-aqueous sol, a complex oxide coating sol for metal and ceramic substrate and a organic-inorganic hybrid coating sol for polymer substrate was prepared and it's hydrophilicity depending on UV irradiation conditions was evaluated. As a conclusions, the following results were obtained. (1)Aqueous titania sol The average particle size of titania in formed aqueous titania sol was distributed between 20$\sim$90nm range depending on reaction conditions. And the crystal phase of titania powders obtained by frozen drying method was changed from amorphous state to anatase and subsequently transformed to rutile crystal phase and it is attributed to concentration gradient in aqueous sol. (2)Non-aqueous titania sol Non-aqueous titania sol was prepared using methanol as a solvent and a little distilled water for hydrolysis and nitric acid as a catalyst were used. The obtained non-aqueous titania sol was stable at room temperature for 20 days. Additionally, non-aqueous titania sol with addition of chealating reagent such as acethylaceton and ethylene glycol prolonged the stability of sol by six months. (3)Complex sol and hybrid sol with super hydrophilicity The above mentioned aqueous titania sol as a main photocataylic component and non-aqueous titania sol as a binder for coating process was used to prepare a complex sol used for metal, ceramic and wood material substrate and also to prepare the organic-inorganic hybrid sol for polymer substrate such as polycarbonate and polyethylene, in which process APMS(3-Aminopropyltrimethoxysilane), GPTS(3-Glycidoxypropyl-trimethoxysilane) as a hydrophilic silane compound and HEMA(2-Hydroxyethyl methacrylate) as a forming network in hybrid coating film were used. The hybrid coating film such as prepared through this process showed a superhydrophilicity below 1$10^{\circ}$ depending on processing conditions and a pencil's hardness over 6 H.

• 한국해양학회지
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• v.25 no.1
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• pp.8-20
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• 1990

A series of pore water data were obtained during the different time over one year period between October 1987 and October 1988, from a site on a muddy intertidal flat, located in the Kyeong-gi Bay, west coast of Korea, The results have revealed that the tidal flat is an environment of active nutrient the subface supplied by the overlying seawater is almost completely removed from the pore water at depth of about 10 cm below the sediment surface. The nutrients such as ammonium and phosphate are produced through this process and subsequently accumulated in the pore water forming steep gradients near the sediment surface. Below the main sulfate redirection zone, a secondary peak of dissolved sulfate was often observed. Greal seasonal variation of the pore water nutrient profiles was observed, which was particularly clear in their maximum concentration as well as in their concentration gradient. The rate constants of sulfate reduction and nutrient regeneration, estimated by using a diagenetic model (Berner, 1980), differ by an order of magnitude between the summer and winter seasons. The difference in sediment temperature may account for most of the calculated variation. The C:N:P ratio, calculated from the pore water nutrient gradients also exhibits a slight seasonal difference. The organic matter being decomposed by sulfate reduction appears to be depleted in depleted in nitrogen, compared to the average marine organic matter.