• Journal of The Korean Society of Agricultural Engineers
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• v.49 no.5
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• pp.11-20
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• 2007

In this study, we reviewed the optimal space for the fishway and fish storage establishment in the section between the downstream of the Hwacheon dam and the confluence of the Pungsan river. The hydraulic stability of these facilities was also examined. In the section between the downstream of Hwacheon dam and the confluence of Pungsan river, the release flow of Hwacheon dam was set at $5,495m^3/s,\;6,110m^3/s$ and $7,537m^3/s$, and numerical simulations were executed for each instance using the HEC-RAS model and RMA-2. In the analysis of the flow velocity distributions in the subject section by release flows of Hwacheon dam, it was shown that there was over 5.0m/s of high flow velocity at Sta. $#1{\sim}Sta.$ #3, Sta. $#4{\sim}Sta.$ #6, and Sta. $#12{\sim}Sta.$ #13 of the sections analyzed in this study. The Sta. $#0{\sim}Sta.$ #1 was considered appropriate for the fishway and fish storage establishment. As seen in the results of the numerical stability review by release flow conditions of Hwacheon dam subject to the selected available areas fur fishway and fish storage, the topographically available section for the establishment of fishway and fish storage exists at Sta. $#1{\sim}Sta.$ #3 when the release flow of Hwacheon dam is $5,495m^3/s$, whereas Sta. $#0{\sim}Sta.$ #1 should be reviewed for the subject section for the establishment of fishway at release flows of $6,110m^3/s$ and $7,537m^3/s$, in addition to the figures gathered at the $5,495m^3/s$ release flow. Finally, the available section for the establishment of fishway and fish storage was determined to be Sta. $#0{\sim}Sta.$ #3. Further, if fishway and fish storage are established in the outer bank within this section, the high flow velocity section should be avoided. An alternative would be to establish for the fishway in the inner band on the section of Sta. #1 or Sta. #3.

• Journal of Electrical Engineering and Technology
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• v.12 no.4
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• pp.1641-1648
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• 2017

Many researchers had examined the validity of using the high-to-low ratio between two fixed frequency band amplitudes (H/L-FFB) from the surface electromyography of a face and body as the first spectral index to assess muscle fatigue. Despite these studies, the disadvantage of this index is the lack of a criterion for choosing the optimal border frequency. We tested the potential of using the high-to-low ratio between two signal spectral moments (H/L-SSM), without fixed border frequencies, to evaluate muscle fatigue and predict endurance time ($T_{end}$), which was determined when the subject was exhausted and could no longer follow the fixed contraction cycle. Ten healthy participants performed five sets of voluntary isotonic contractions until they could only produce 10% and 20% of their maximum voluntary contraction (MVC). The $T_{end}$ values for all participants were $138{\pm}35s$ at 10% MVC and $69{\pm}20s$ at 20% MVC. Changes in conventional spectral indices, such as the mean power frequency (MPF), Dimitrov spectral index (DSI), H/L-FFB, and H/L-SSM, were extracted from surface EMG signals and were monitored using the initial slope computed every 10% of $T_{end}$ as a statistical indicator and compared as a predictor of $T_{end}$. Significant correlations were found between $T_{end}$ and the initial H/L-SSM slope as computed over 30% of $T_{end}$. In conclusion, initial H/L-SSM slope can be used to describe changes in the spectral content of surface EMG signals and can be employed as a good predictor of $T_{end}$ compared to that of conventional spectral indices.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.152-157
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• 2004

Gluten was extracted from domestic wheat flour using UTH buffer (4 M urea in 0.1 M Tris-HCl, pH 8.6) and validated by SDS-PAGE analysis for production of wheat flour products with reduced gluten content.. Anti-gluten polyclonal antibody was made by administering extracted gluten fraction on animal model. Anti-gluten serum titer of extracted gluten fraction was evaluated by ELISA, and that of antibody titer according to administration period. Anti-gluten sera were used for ELISA and immunoblot analysis before and after hydrolysis of gluten fraction at optimal pH and temperature condition for each protease. Gluten fraction separated by SDS-PAGE showed several bands covering 75 to 10 kDa, in which anti-gluten sera were 25, 34, and 45 kDa. Enzyme hydrolysis of gluten fraction revealed protein band sizes to be lower than 15 kDa. Content of pretense from bovine pancreas (b.p. protease) for gluten hydrolysis was estimated as 1 mg in 10 mL gluten fraction extracted for 4 hr.

• Journal of Broadcast Engineering
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• v.19 no.4
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• pp.491-501
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• 2014

Recently, the need for disaster-preventing broadcast has increased gradually to cope with natural disaster like earthquake and tsunami causing enormous losses of both life and property. In disaster-preventing broadcast system, the wake-up signal is used to alert user terminal and switch the current state of channel to the emergency channel, which is for the fast and efficient delivery of emergency information. In this paper, we propose the detection method of wake-up signal for disaster-preventing broadcast systems. The wake-up signals for disaster-preventing broadcast should have a good auto-correlation property in low power and narrow-band conditions that does not affect the existing digital television (DTV) system. The suitability of the m-sequence and complementary code (CC) is analyzed for wake-up signals according to signal to noise ratio. A wake-up signal is proposed by combining the direct sequence spread spectrum (DSSS) technique and pseudo noise (PN) sequences such as Barker and Walsh-Hadamard codes. By using the proposed method, a higher detecting performance can be achieved by the spreading gain compared to the single long m-sequence and the Golay code.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.3
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• pp.185-195
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• 2002

The purpose of this study is to evaluate and seek the best suitable band and threshold boundary level on the change detection of image differencing method using Landsat TM data(20 May 1987 and 20 May 1993) in Pyeongtaeg City. The change detection images differencing method were evaluated by using normal reference data with an optimal threshold level{$mean{\pm}(SD{\times}T$ value). The normal reference data consisted of positive change{change dark into light in image pattern, that is, it changed arable land(paddy, upland, forest and so on) to artificial area(buildings, vinyl-house and roads, etc)} and negative change(change light into dark in image pattern, that is, it changed artificial area into arable land). As the result, the kappa coefficients of visible bands(D1, D2 and D3) were higher than those of infrared bands(D4, D5 and D7), and than D1 image with 1.0 thresholding and normal reference data was a improved result in the land-surface change detection such as kappa coefficient : 68.4%, overall accuracy : 89.2%, negative change : 6.6%, positive change : 10.6%.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.419-426
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• 2006

A thermophilic microorganism, strain JE 375, which produces a thermostable protease, was isolated from soil and compost in Korea. This gram-positive, rod-shaped, catalase positive, motility positive, and hemolysis ${\beta}$ containing organism was implicated in glucose fermentation, mannitol fermentation, xylose oxidation, aerobic activity and spore formation. The color of the colony was yellowish white. The temperature range for growth at pH 6.5 was between 55 and $70^{\circ}C$, with an optimum growth temperature of $65^{\circ}C$. This result confirmed the strain JE 375 as a thermophilic microorganism. The enzyme was produced aerobically at $65^{\circ}C$ during 20 hr in a medium (pH 6.5) containing 1% trypton. 1% maltose, 0.5% yeast extract and 1% NaCl. The 16S rDNA of strain JE 375 had 97.6% sequence similarity with the 16S rDNA of Bacillus caldoxyloyticus. On the basis of biochemical and physiological properties and phylogenetic analysis, we named the isolated strain as Bacillus sp. JE 375. The thermostable protease from Bacillus sp. JE 375 had been partially purified and characterized. The molecular weight of the enzyme was deduced from SDS-PAGE and gel chromatography as 55 kDa and its optimal temperature was $60^{\circ}C$. The enzyme showed its highest activity at pH 7.5 and was stable from pH 7.0 to 8.0.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.1
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• pp.15-22
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• 2008

In this paper, we propose a numerical analysis on reversed current of distributed amplifier based on transmission line theory and proposed a theory to obtain optimum transmission line length to minimize the reversed currents by cancelling those components. The reversed current is analyzed as being simply absorbed into the terminal resistance in the conventional analysis. In the proposed analysis, however, they are designed to be cancelled by each other with opposite phase by the optimal length of the transmission lint Circuit simulation and implementation using pHEMT transistor were performed to validate the proposed theory with the cutoff frequency of 3.6 GHz. From the measurement, maximum gain of 14.5dB and minimum gain of 12.3dB were achieved In the operation band. Moreover, measured efficiency of the proposed distributed amplifier is 25.6% at 3 GHz, which is 7.6%, higher than the conventional distributed amplifier. Measured output power Is about 10.9dBm, achieving 1.7dB higher output power than the conventional one. Those improvement is thought to be based on the cancellation of refersed current.

• Journal of the Mineralogical Society of Korea
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• v.19 no.2 s.48
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• pp.81-88
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• 2006

The Yttria Partially Stabilized Zirconia powder was prepared by spontaneous precipitation method using $ZrOCl_2{\cdot}8H_O-YCl_33{\cdot}6H_2O$ solution as a starting materials. The optimal experimental conditions such as concentration and pH of starting solutions, the amounts of stabilizer $Y_2O_3$ used, and sintered temperature were carefully studied. The best condition for synthesizing $ZrO_2$ was experimentally selected and applied throughout this study for the preparation of the 3 mole% $Y_2O_3$ partially stabilized zirconia, 3YSZ. The physical properties of 3YSZ was examined by XRD, Raman, DT A, and SEM. The structural transition from pure monoclinic high temperature $ZrO_2$ to tetragonal room temperature 3YSZ was made possible by the added amount of $Y_2O_3$ in the $ZrO_2+Y_2O_3$ system. All Raman Spectrum band appeared in the lower wave numbers rather than in higher wave numbers as structure changes from monoclinic to tetragonal.

• Applied Biological Chemistry
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• v.44 no.4
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• pp.219-223
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• 2001

Effects of hemoglobin (Hgb) concentration and degree of hydrolysis (DH) of Hgb on the separation of heme-iron were examined to produce highly enriched heme-iron from Hgb hydrolysate. Separation efficiency of Hgb hydrolysate with different DH was studied at wide pH range (pH $1.0{\sim}11.0$). Separation efficiency expressed as heme-iron/peptide ratio increased with decreasing Hgb concentration. When 5% Hgb (pH 10.0) was hydrolyzed using commercially available Esperase for 5 h at $50^{\circ}C$, DH was 25%. The precipitation of heme-iron-enriched peptides were remarkably high at pH range $3{\sim}6$. Optimal pH range for heme-iron with high heme-iron/peptide ratio shifted to acidic pH with increasing DHs of Hgb. The enriched heme-iron fraction in the precipitates showed a single band through urea-SDS-PAGE, with a molecular mass of 1 kDa. In the dry heme-iron product produced in a pilot bioreactor, content of heme-iron and heme-iron/peptide ratio were 27.1 and 38.7%, respectively, and production yield was 9.3%.

• Korean Journal of Veterinary Research
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• v.36 no.1
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• pp.109-118
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• 1996

The Salmonella rfb gene encoding for the biosynthesis of the oligosaccharide-repeating units of the O-antigenic determinants was cloned and sequenced. A set of nucleotide primers(a forward and reverse) was selected to target a defined region of the guanosine diphospho-mannose(GDP-Man) pyrophosphorylase synthase gene : rfbM of Salmonella C serogroup. The primer set was used to develop a PCR-based rapid and specific detection system for Salmonella C1 serogroup. Amplification bands of predicted size(1,422bp) were generated from 11 different Salmonella C1 isolates. The bands were verified to be specific for the C1 serogroup by Southern blot analysis using reference homologous DNA specificity was further confirmed by the lack of reactivity with heterologous DNA derived from non-salmonella members of the family enterobacteriaeceae. A specificity of 100% was deduced along with a very high sensitivity shown by a detection limit of 1fg of a purified DNA template. The isolated DNA sequence was found to be 99.8% homologous to S montevideo but the related primers amplified with the predicted band sizes with all the Salmonella C1 serogroups tested. It is concluded that the PCR protocol based on the rfbM gene from S cholerasuis is optimal fast and specific for the detection of Salmonella C1 serogroup and also the corresponding probe is suitable for rapid detection of all Salmonella C1 serogroup DNA tested. This technology should facilitate the identification of contaminated pig products and for any other products contaminated with the Salmonalla C1 serogroup. The immediate impact of this developed method will be in the area of food safety of pig products with the potential prospect for adaptation to other food inspection technologies.