• Journal of the Korea Organic Resources Recycling Association
• /
• v.18 no.2
• /
• pp.76-83
• /
• 2010

We(Hansol EME Co. Ltd.) proceeded anaerobic digestion test for domestic food wastewater applying to two operating method for increasing of OLR. The methods are as follows. One was the rapidity operating method which was increasing the OLR continuously and rapidly and the other was the terraced operating method which was increasing the OLR having adaptation period for each step. As a result of this tests, the ratio of VFA/Alkalinity of the process was very unstable under the rapidity operating method then the volume of produced biogas was dramatically decreased. However the process was shown stable performance under the terraced operating method maintaining the ratio of VFA/Alkalinity less than 0.4. Also, the process was performing the biogas recovery of $0.8Nm^3/kgVS_{rem}/d$ and the VS removal ratio of 85%. T-RFLP analysis about the community of bacteria and methanogen is also conducted to check the change of the microbial community according to the methods of OLR increasing operation. The microbial community was changed by the methods of OLR increasing operation according to the result of T-RFLP analysis. Although the anaerobic digestion test was executed by same pilot plant, the reactivity and the tolerance of microbial community for surrounding environment could be considerably changed by the operating method for the process.

• Journal of Broadcast Engineering
• /
• v.21 no.4
• /
• pp.506-514
• /
• 2016

In this study, HEVC over DVB-T2 systems with a bandwidth of 6 MHz is considered, particularly for the terrestrial 4K-UHDTV broadcasting service in the Republic of Korea. The threshold of visibility carrier-to-noise power ratio (ToV C/N) and the receiver minimum required input level (sensitivity) for satisfying the subjective picture failure (SPF) condition are measured in the laboratory. It is observed, for transmitting 26.37 Mbps data stream correctly, that ToV C/N is 18.8 dB on average, and the receiver sensitivity is varied from minimum -84.2 dBm to maximum -80.0 dBm. Based on the results, the receiver noise floor is calculated by -100 dBm on average.

• Transactions on Electrical and Electronic Materials
• /
• v.18 no.1
• /
• pp.30-34
• /
• 2017

The building integrated photovoltaic system (BIPV) attracts attention with regard to the future of the photovoltaic (PV) industry. It is because one of the promising national and civilian projects in the country. Since land area is limited, there is considerable interest in BIPV systems with a variety of angles and shapes of PV panels. It is therefore expected to be one of the major fields for the PV industry in the future. Since the irradiation is different from each installation angle, the output can be predicted by the angles. This is critical for a PV system to be operated at maximum power and use an efficient design. The development characteristics of tilted angles based on data results obtained via long-term monitoring need to be analyzed. The ratio of the theoretically available and actual outputs is compared with the installation angles of each PV module to provide a suitable PV system for the user.

• Proceedings of the Korean Society of Medical Physics Conference
• /
• 2003.09a
• /
• pp.76-76
• /
• 2003

Purpose: To assess clinical proton MR spectroscopy (MRS) as a noninvasive method for evaluating tumor malignancy at 3T high field system. Methods: Using 3T MRI/MRS system, localized water-suppressed single-voxel technique in patients with brain tumors was employed to evaluate spectra with peaks of N-acetyl aspartate (NAA), choline-containing compounds (Cho), creatine/phosphocreatine (Cr) and lactate. On the basis of Cr, these peak areas were quantificated as a relative ratio. Results: The variation of metabolites measurements of the designated region in 10 normal volunteers was less than 10%. Normal ranges of NAA/Cr and Cho/Cr ratios were 1.67$\pm$018 and 1.16:1:0.15, respectively. NAA/Cr ratio of all tumor tissues was significantly lower than that of the normal tissues (P=0.005). Cho/Cr ratio of high-grade gliomas was significantly higher than that of low-grade gliomas (P= 0.001), Except 4 menigiomas, lactate signal was observed in all tumor cases. Conclusions: The present study demonstrated that the neuronal degradation or loss was observed in all tumor tissues. Higher grade of brain tumors was correlated with higher Cho/Cr ratio, indicating a significant dependence of Cho levels on malignancy of gliomas. This results suggest that clinical proton MR spectroscopy could be useful to predict tumor malignancy. Acknowledgement: This study was supported by a grant of the Mid and Long Term Nuclear R/D Plan Program, Ministry of Science and Technology, Republic of Korea.

• Journal of Welding and Joining
• /
• v.28 no.6
• /
• pp.28-34
• /
• 2010

This paper was described on investigation to prevent porosity in high speed MIG Welding of Al 6082-T6. Porosity measurement was carried out by using image analysis of micrographs with the help of an analysis software. The main parameter was arc length and torch progressive angle. The porosity ratio was increased as arc length was increased. The arc length was increased depending upon the output voltage. By proper selection of pulse waveform parameter, the stable arc of one pulse one drop was generated. The porosity ratio of optimum condition in one pulse one drop was lower than high voltage condition. When torch progressive angle was an angle of advance $10^{\circ}$, porosity ratio was minium.

• The Korean Journal of Nuclear Medicine
• /
• v.31 no.3
• /
• pp.365-371
• /
• 1997

The aim of this study is to evaluate the efficiency of the pulmonary perfusion scan(Pp scan) in the experimental animal single lung transplantation. Eight left lung transplanted mongrel dogs were included in this study. The serial Pp scan with 111MBq $^{99m}TC-MAA$ were done at the periods of immediate postoperative period, POD 3 days, and POD 10-14 days and finally autopsy was done in each cases. The transplanted lung perfusion was analysed as a percentage radioactivity of trans planted/native lung(T/N) ratio. The Pp scan of a donor mongrel dog was used as a reference(left/right lung (T/N) ratio 85.2%). The average T/N ratio of all cases on immediate postoperative state(reperfusion injury) : 19.2%, three acute rejections. 12.6%, three bronchial dehiscences 6.1% and two pulmonary thromboses : 2.0%. Two cases showed moderate improvement of reperfusion injury as increasing the T/N ratio in POD 3 days Pp scan. The T/N ratio showed sequentially decreased in six cases. As a conclusion, the Pp scan could be a non-invasive method in the evaluation of the experimental one-lung transplanted mongrel dog.

• The Korean Journal of Ecology
• /
• v.7 no.2
• /
• pp.74-84
• /
• 1983

The dominant species of the sand vegetation in the western coast of Korea were Carex pumila, Ischaemum antheporoides, Calystegia soldanella, Carex kobomugi and Imperata cylindrica var. koenigii. The salt content of the sand dune soil and of the atmosphere of surveyed areas ranged from 3.93 to 13.86 mg% and from 25.81 to 168.86mg% respectively. Between the salt content of the atmosphere and that of the soil positive relationship was found. Species density and Simpson's index increased with the distance from the coast, the former was exponential, however, the latter was linear. The composition of biological types in the investigated stands were H-D4-R1-3-e or H-D4-R1-3-t. Relative numbers of psammophytes and rhizome psammophytes decreased with the distance from the coast, but those of other plants increased. The standing crop of the sand dune vegetation ranged from 0.04 to 491.64g/m2 and the average 27.77g/m2. This was varied as the stands and showed a linear increment as the distance from the coast was increased. The salt content of atmosphere significantly affected the density, T/R ratio in the standing crop and Simpson's index. The salt content of soil showed similar tendency on the density and the T/R ratio.

• Magazine of the Korea Concrete Institute
• /
• v.7 no.5
• /
• pp.133-144
• /
• 1995

This study investigated to the properties of structural behaviors through a series of experiment with the key parameter, such as diameter-to-thickness(D/t) ratio, selenderness ratio of steel t~ube and strength of concrete under loading condition simple confined concrete by steel tube as a fundmental study on adaptability with structural members in high-rise building. The obtained results are sumnarised as follow. (1) The fracture mode of confined concrete was presented digonal tension fracture in the direction of $45^{\circ}$ with compression failure at the end of specimen in stub column, but the fracture mode of long column was assumed an aspect of bending fracture transversely. (2) The deformation capacity and ductility effect was increased by confine steel tube for concrete. (3) 'The emprical formula to predict the ultimate capacity of confined concrete by steel tube and concrete filled steel tube column using restraint of concrete considered D / t ratio, selenderness ratio of steel tube anti strength of' concrete were proposed.

• Asian-Australasian Journal of Animal Sciences
• /
• v.14 no.3
• /
• pp.338-345
• /
• 2001

An experiment was conducted to determine the optimal inclusion ratio of spray dried plasma protein (SDPP) and dried porcine solubles (DPS) for maximizing growth and improving immunity in weaned pigs. One hundred-fifty male (barrow) pigs were allotted in a completely randomized block design. Treatments were as follows: 1) control (6% SDPP), 2) S6D6 (6% SDPP+6% DPS), 3) S6D3 (6% SDPP+3% DPS), 4) S3D6 (3% SDPP+6% DPS) and 5) S3D3 (3% SDPP+3% DPS). Each treatment has 6 replicates with 5 pigs per replicate. Average daily gain (ADG) and average daily feed intake (ADFI) were highest, but not significantly different when pigs were fed a diet contained 6% SDPP and DPS from d 0 to 7 after weaning. Pigs fed the S6D3 diet showed better weight gain and feed intake than other treatments, especially compared with pigs fed S3D6 diet (p<0.05) from d 8 to 21 after weaning. For the overall experimental period, pigs fed the S6D3 diet showed the best improvement in ADG and ADFI. The digestibilities of dry matter (DM) and crude protein (CP) were higher in pigs fed the S6D6 diet than other diets from d 0 to 7 after weaning. However, pigs fed S6D3 diet showed higher DM, CP and essential amino acids (except methionine and arginine) digestibilities than pigs fed other diets from d 8 to 21 after weaning, although there was no significant difference. From d 8 to 21 after weaning, threonine, valine, isoleucine and leucine digestibilites were higher in S6D6 group, and phenyalanine, histidine, lysine and arginine digestibility were higher in S6D3 group than other groups. The ratio of CD4 and CD8 positive lymphocytes during the overall experimental period was independent of the ratio of SDPP and DPS. However, CD4+:CD8+ ratio was numerically lowered in pigs fed diet the S6D3 diet. Therefore, the present study suggests that an optimal inclusion ratio for maximizing growth performance and maintaining low immune status is 6% of SDPP and 3% of DPS in weaned pigs.

• Journal of Ginseng Research
• /
• v.45 no.5
• /
• pp.591-598
• /
• 2021

Background: Hematopoiesis is the production of blood cells from hematopoietic stem cells (HSCs) that reside in the bone marrow. Cyclophosphamide (CTX) is a chemotherapy drug that suppresses the immune system. Korean Red Ginseng (KRG) and Colla corii asini (CCA) have been traditionally used for boosting the immune system. Methods: HSCs in the bone marrow, and immune cell subtype in splenocytes, PBMCs, and thymocytes were investigated. Serum levels of hematopoietic-related markers were analyzed using ELISA. Protein expression in spleen tissue was analyzed using western blot analysis. Hematoxylin & eosin staining in the femurs of mice were also conducted. Results: The combination of KRG and CCA with a ratio of 3:2 increased HSCs, CD3 and CD8⁺ T cells in the circulation, and CD3 T cells in the spleen. A ratio of 2:3 (KRG:CCA) increased the thymic regulatory T cells and recovered the CD3 T cells in the spleen and circulation while recovering proteins in the JAK-STAT pathway in the spleen. Overall, blood cell population and differentiating factors vital for cell differentiation were also significantly recovered by all combinations especially in ratios of 3:2 and 2:3. Conclusion: A ratio of 3:2 (KRG:CCA) is the most ideal combination as it recovered the HSC population in the bone marrow of mice.