• Journal of Korean Society of Environmental Engineers
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• v.36 no.11
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• pp.753-757
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• 2014

Anode electrode in a microbial fuel cell (MFC) should transfer the receiving electron as well as provide large surface area that can be immobilized microorganisms. Microorganisms' population is one of important factors to improve the current generation and to treat the livestock wastewater by biological treatment. These studies were attempted to investigate if stainless-steel wire skein (SSWS) could be used as anode electrode replacement a graphite felt electrode in microbial fuel cell. For these studies, pretreated livestock wastewater was used diluted to 500 mg/L as COD before use. At this time, the current showed a little difference of about 5% when using each of a SSW and graphite felt (control). There was no significant difference in the current value. The organic removal rate in the microbial fuel cells used graphite felt and SSWS was 82.4% and 88.3%, respectively. The COD removal in the MFC used the SSWS was higher than that of graphite felt. Ammonium nitrogen was showed similar trend in two case all. These results about current generation and organic matter reduction seem possible that SSWS was used to anode electrode. When SSWS is used, the initial investment for system construction is expected to be able to reduce by approximately 1/50.

• The Journal of Engineering Geology
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• v.24 no.4
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• pp.487-499
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• 2014

While the vertical open type of heat exchanger is more effective in areas of abundant groundwater, and is becoming more widely used, the heat exchanger most commonly used in geothermal heating and cooling systems in Korea is the vertical closed loop type. In this study, we performed numerical simulations of the optimal utilization of geothermal energy based on the hydrogeological and thermal properties to evaluate the efficiency of the vertical open type in areas of abundant groundwater supply. The first simulation indicated that the vertical open type using groundwater directly is more efficient than the vertical closed loop type in areas of abundant groundwater. Furthermore, a doublet system with separated injection and extraction wells was more efficient because the temperature difference (${\Delta}$) between the injection and extraction water generated by heat exchange with the ground is large. In the second simulation, we performed additional numerical simulations of the optimal utilization of geothermal energy that incorporated heat transfer, distance, flow rate, and groundwater hydraulic gradient targeting a single well, SCW (standing column well), and doublet. We present a flow diagram that can be used to select the optimal type of heat exchanger based on these simulation results. The results of this study indicate that it is necessary to examine the adequacy of the geothermal energy utilization system based on the hydrogeological and thermal properties of the area concerned, and also on a review of the COP (coefficient of performance) of the geothermal heating and cooling system.

• Journal of the Korean Society of Radiology
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• v.3 no.1
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• pp.29-39
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• 2009

In this paper has proposed to the recognition of the disease on medical images using neural network. The neural network is constructed as three-layers of the input-layer, the hidden-layer and the output-layer. The training method applied for the recognition of disease region is adaptive error back-propagation. The low-frequency region analyzed by DWT are expressed by matrix. The coefficient-values of the characteristic polynomial applied are n+1. The normalized maximum value +1 and minimum value -1 in the range of tangent-sigmoid transfer function are applied to be use as the input vector of the neural network. To prove the validity of the proposed methods used in the experiment with a simulation experiment, the input medical image recognition rate the evaluation of areas of disease. As a result of the experiment, the characteristic polynomial coefficient of low-frequency area matrix, conversed to 4 level DWT, was proved to be optimum to be applied to the feature parameter. As for the number of training, it was marked fewest in 0.01 of learning coefficient and 0.95 of momentum, when the adaptive error back-propagation was learned by inputting standardized feature parameter into organized neural network. As to the training result when the learning coefficient was 0.01, and momentum was 0.95, it was 100% recognized in fifty-five times of the stomach image, fifty-five times of the chest image, forty-six times of the CT image, fifty-five times of ultrasonogram, and one hundred fifty-seven times of angiogram.

• Archives of Reconstructive Microsurgery
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• v.11 no.2
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• pp.153-161
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• 2002

Purpose : Plantar surfaces, calcaneal area, and region of Achilles insertion, which are extremely related with weight-bearing area and shoes application, must be reconstructed with glabrous and strong fibrous skin. Numerous methods of reconstructing defects of these regions have been advocated, but the transfer of similar local tissue as a cutaneous flap with preservation of sensory potential would best serve the functional needs of the weight-bearing and non-weight-bearing surfaces of this region. Therefore it is recommended to use the limited skin of medial surface of foot that is similar to plantar region and non-weight-bearing area. In this paper we performed the medial plantar flap transfered as a fasciocutaneous island as one alterative for moderate-sized defects of the plantar forefoot, plantar heel, and area around the ankle in 25 cases and report the result, availability and problem of medial plantar flap. Materials and methods : We performed proximally based medial plantar flap in 22 cases and reverse flow island flap in 3 cases. Average age was $36.5(4{\sim}70)$ years and female was 3 cases. The causes of soft tissue defect were crushing injury on foot 4 cases, small bony exposure at lower leg 1 case, posterior heel defect with exposure of calcaneus 8 cases, severe sore at heel 2 cases, skin necrosis after trauma on posterior foot 4 cases, and defect on insertion area of Achilles tendon 6cases. Average follow up duration was 1.8(7 months-9.5 years) years. Results: Medial plantar flaps was successful in 22 patients. 18 patients preserved cutaneous branches of medial plantar nerve had sensation on transfered flap but diminished sensation or dysesthesia. At the follow up, we found there were no skin ulceration, recurrence of defect or skin breakdown in all 18 patients. But there was one case which occurred skin ulceration postoperatively among another 4 cases not contained medial plantar nerve. At the last follow up, all patients complained diminished sensation and paresthesia at medial plantar area distally to donor site, expecially with 4 patients having severe pain and discomfort during long-time walking. Conclusion : Medial plantar island flap based on medial plantar neurovascualr pedicle have low failure rate with strong fibrous skin and preserve sensibility of flap, so that it is useful method to reconstruct the skin and soft tissue defect of foot. But it should be emphasized that there are some complications such like pain and paresthesia by neuropraxia or injury of medial plantar nerve at more distal area than donor site. We may consider that medial plantar flap have limited flap size and small arc of rotation, and require skin graft closure of the donor defect and must chose this flap deliberately.

• Journal of fish pathology
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• v.22 no.3
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• pp.375-382
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• 2009

Integration and expression of a target gene into chromosomal genomes of host cell by retrovirus mediated gene transfer system usually require complicate and laborious procedures. In the present study, we investigate a simple method to integrate a target gene into genome of BF-2 cells using ultraviolet (UV)-inactivated snakehead retrovirus (SnRV), a fish retrovirus. First of all, an optimization of transfection condition was determined with BF-2 cells using Lipofectamine 2000 and Transome. Using 0.5 $\mu\ell$ Lipofectamine 2000 resulted in 33.8, 40.6 and 40.2% of transfection efficacy with high survival rate (minimum 80%) in 0.5, 1 and 2 $\mu{g}$ DNA, respectively, and those of Transome were all less than 5%. It was confirmed that UV-treatment for 5 min was enough to inactivate infectivity of SnRV. Next, a cassette composed of GFP (green fluorescent protein) gene flanked by LTR (long terminal repeats) sequences derived from SnRV was constructed and transfected into BF-2 cells followed by treatment with UV-inactivated SnRV for optimization of integration and expression of the cassette gene. As the results, the fluorescence was expressed in BF-2 cells treated with UV-inactivated SnRV 3 and 5 times, while there was no expression in BF-2 cells with once and non treatment. Accordingly, it was confirmed that GFP gene was integrated into chromosomal genome of BF-2 cells with UV-inactivated SnRV.

• Korean Journal of Remote Sensing
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• v.32 no.5
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• pp.435-452
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• 2016

Land Surface Temperature (LST) has been operationally retrieved from the Communication, Ocean, and Meteorological Satellite (COMS) data by the spilt-window method (CSW_v2.0) developed by Cho et al. (2015). Although the CSW_v2.0 retrieved the LST with a reasonable quality compared to the Moderate Resolution Imaging Spectroradiometer (MODIS) LST data, it showed a relatively poor performance for the strong inversion and lapse rate conditions. To solve this problem, the LST retrieval algorithm (CSW_v2.0) was updated using the simulation results of radiative transfer model (MODTRAN 4.0) by considering the diurnal variations of air temperature. In general, the upgraded version, CSW_v3.0 showed a similar correlation coefficient between the prescribed LSTs and retrieved LSTs (0.99), the relatively smaller bias (from -0.03 K to-0.012 K) and the Root Mean Square Error (RMSE) (from 1.39 K to 1.138 K). Particularly, CSW_v3.0 improved the systematic problems of CSW_v2.0 that were encountered when temperature differences between LST and air temperature are very large and/or small (inversion layers and superadiabatic lapse rates), and when the brightness temperature differences and surface emissivity differences were large. The bias and RMSE of CSW_v2.0 were reduced by 10-30% in CSW_v3.0. The indirect validation results using the MODIS LST data showed that CSW_3.0 improved the retrieval accuracy of LST in terms of bias (from -0.629 K to -0.049 K) and RMSE (from 2.537 K to 2.502 K) compared to the CSW_v2.0.

• Journal of Plant Biotechnology
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• v.38 no.2
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• pp.105-116
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• 2011

Transgenic zoysiagrass (Zoysia japonica Steud.) expressing the bar gene inserted in the plant genome has been generated previously through Agrobacterium tumefaciens-mediated transformation. The GM zoysiagrass (event: JG21) permits efficient management of weed control of widely cultivated zoysiagrass fields, reducing the frequency and cost of using various herbicides for weed control. Now we have carried out the environmental risk assessment of JG21 prior to applying to the governmental regulatory agency for the commercial release of the GM turf grass outside of test plots. The morphological phenotypes, molecular analysis, weediness and gene flow from each test plot of JG21 and wild-type zoysiagrasses have been evaluated by selectively analyzing environmental effects. There were no marked differences in morphological phenotypes between JG21 and wild-type grasses. The JG21 retained its stable integration in the host plant in T1 generation, exhibiting a 3:1 segregation ratio according to the Mendelian genetics. We confirmed the copy number (1) of JG21 by using Southern blot analysis, as the transgenic plants were tolerant to ammonium glufosinate throughout the culture period. From cross-fertilization and gene flow studies, we found a 9% cross-pollination rate at the center of JG21 field and 0% at distances over 3 m from the field. The JG21 and wild-type zoysiagrass plants are not considered "weed" because zoysiagrasses generally are not dominant and do not spread into weedy areas easily. We assessed the horizontal gene transfer (HGT) of the transgene DNA to soil microorganisms from JG21 and wild-type plants. The bar gene was not detected from the total genomic DNA extracted from each rhizosphere soil of GM and non-GM Zoysia grass fields. Through the monitoring of JG21 transgene's unintentional release into the environment, we found no evidence for either pollen mediated gene flow of zoysiagrass or seed dispersal from the test field within a 3 km radius of the natural habitat.

• Korean Journal of Animal Reproduction
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• v.17 no.3
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• pp.233-242
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• 1993

The effects of in vitro maturation and sperm treatment condition on the in vitro fertilization (IVF) and developmental capacity of bovine oocytes were investigated and the development of embryos was compared under the 2 different co-culture system, with GC or BOEC. The cultured embryo to 16 cell or morula wre transferred into recipients or frozen by 2 different freezing method. The results obtained were summarized as follows; 1. In vitro maturation rates of vovine follicular oocytes cultrued in TCM199 with 10% FCS or ECS were 64.0% and 72.7%, but the case of addition of 10% FCS or ECS to TCM199 co-cultured with granulosa cells were 81.3% and 84.0%, respectively. IVM rate of three TCM199 added to granulosa cells was higher than that of media without granulosa cells. 2. When bovine follicular oocytes were matured in TCM199 with 10% FCS and GC and then fertilized in vitro by sperm treated with caffeine, embryo developments of bovine oocytes co-cultured with BOEC were 38.4% and 51.4%, respectively. But those of bovine oocytes co-cultured with GC were 52.2% by sperm treated with caffeine-heparin. 3. Cleavage rates of bovine oocytes cultured with 10% FCS alone and fertilized in vitro by sperm treated with caffeine-heparin was 33.0%. 4. When bovine follicular oocytes were matured in TCM199 with 10% FCS and GC, embryo developments of bovine ooctyes co-cultured with BOEC of GC were 46.0% and 50.2%, respectively. 5. When bovine follicular oocytes were matured in TCM199 with 10% ECS and GC, embryo developments co-cultured with BOEC or GC were 45.2% and 51.4%, respectively. 6. When Korean Native cow's follicular oocytes matured in TCM199 with 10% FCS and GC, embryo developed co-cultured with BOEC or GC were 45.2% and 51.4%, respectively. 6. When Korean Native cow's follicular oocytes matured in TCM199 with 10% FCS and GC, embryo developments of the bovine oocyte co-cultured with BOEC and GC were 41.8% and 60.1%. But with FCS 10% those of the bovine oocytes co-cultured with BOEC and GC were 42.0% and 48.4%, respectively. 7. When Holstein's follicular oocytes were matured in TCM199 with 10% ECS and GC, embryo developments fo the bovine oocytes co-cultured with BOEC and GC were 50.0% and 57.7%, but with ECS 10% those of the bovine oocytes co-cultured with BOEC and GC were 52.2% and 56.5%, respectively. 8. The viability of frozen-thawed embryos ranged from 60~80% and those of frozen-thawed embryos from vitrification was lower than that from conventional metiod. 9. The selected fresh embryos were transferred nonsurgically to 7 recipients but did not result in pregnancy.

• Analytical Science and Technology
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• v.25 no.5
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• pp.324-332
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• 2012

Construction era of Pungnabtoseong earthen wall is one of the most popular controversial issues in Korean archaeological research. For the evaluation of construction era, OSL dating was carried out using seven pottery pieces collected in each construction stage. From TL/OSL characteristics, and the results of absolute zeroing test and recovery test, it was proved that the pottery samples were completely bleached. The reliable paleodose was evaluated by using the SAR method with preheat at $220^{\circ}C$, and the pottery OSL age was determined from the ratio of paleodose to annual dose rate. Considering the resultant OSL ages, archaeological context and the related 14C ages, the first construction era was determined as $294{\pm}52$ yrs AD ($1{\sigma}$ SE). Also we found that the enlargement of construction stage III was $328{\pm}30$ yrs AD ($1{\sigma}$ SE) and final construction was finished within $400{\pm}76$ yrs AD ($1{\sigma}$ SE). Therefore, it is suggested that the construction of Pungnabtoseong earthen wall was firstly started in the late $3^{rd}$ century AD and several enlargements and repairs had been carried out, before the transfer of the capital of Baekje dynasty to Woongjin (Gongju) at 475 AD.

• The Journal of the Korean Society for Microbiology
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• v.14 no.1
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• pp.49-61
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• 1979

Two hundred and ninety-five strains of Peudomonas aeruginosa isolated from clinical sources were tested for drug resistance and demonstration of R plasmids by intraspecies conjugation system. Sixty strains were found highly resistant to two or more of drugs. The rate of resistant strains were 38.9% to kanamycin(km), 33.2% to streptomydn(sm), 22.7% to sulfisomidine(Sa), 14.2% to chloramphenicol(Cp), 13.8% to tetracycline(Tc), 3.0% to carbenicillin(Cb), and to gentamicin(Gm), respectively. But no strains was resistant to nalidixic acid and colistine. They were resistant to per milliliter to more than $400{\mu}g$ per ml. of Tc, $800{\mu}g$ per ml of Cp and of Sm, $6,400{\mu}g$ per ml. of Sa, $200{\mu}g$ per ml. of Cb, $100{\mu}g$ per ml. of Gm, and $25{\mu}g$ per ml. of colistine. Forty-three strains of Pseudomonas aeruginosa could be transferred their resistance to Pseudomonas aeruginosa 2-70, 1005 rifampin resistant FP-auxotrophic mutant. Of sixty multiple resistant strains, forty-three(71.6%) demonstrated R plasmids; nineteen carried resistance to(Tc Cp Sm Sa), six to(Tc Cp Sm), three to(Tc Cp Sa), and Cp, five to(Tc Sm Sa), two to(Tc Sa), (Cp Sm) and Tc, and one to(Cp Sm Sa). Degree of resistance of recipients recieving R plasmids from donors were almost the same level of resistance as the donor in regardless of mating temperature at $25^{\circ}C$ and $37^{\circ}C$. Resistance to Tc, Sm, and Sa were transferred to a very few of recipient cells at five minutes after mating with donor and recipient cells but resistance to Cp were transferred to the majority of recipient cells. The transfer frequency of Tc, Cp, Sm, and Sa resistance from donors to recipients were from $1.0^{-1.4}\;to\;1.0^{-3.5}$ at $25^{\circ}C$ for 18 hours of incubation and were from $1.0^{-1.5}\;to\;1.0^{-3.5}$ at $37^{\circ}C$ for 18 hours of incubation.