• Title, Summary, Keyword: 기술적 효율성

Search Result 10,531, Processing Time 0.092 seconds

Evaluation of Antimicrobial, Antioxidant, and Antithrombin Activities of the Rhizome of Various Dioscorea Species (마 품종별 메탄올 추출물의 항균, 항산화 및 항혈전 활성 평가)

  • Kwon, Jung-Bae;Kim, Mi-Sun;Sohn, Ho-Yong
    • Korean Journal of Food Preservation
    • /
    • v.17 no.3
    • /
    • pp.391-397
    • /
    • 2010
  • Yams (Dioscorea spp.) have been used as medicinal and edible resources worldwide. In the present study, methanol extracts were prepared from various kinds of yam, including D. batatas (Gyeongbuk No. 1 and No. 4), D. alata L. (Gyeongbuk No. 5 and No. 6), and D. bulbifera and D. nipponica, and the antioxidant, antithrombin, and antimicrobial activities of these extracts were evaluated. The water content of the various yams was 54.7~83.2% (D. batatas> D. alata L.>D. nipponica>D. bulbifera) and the methanol extracts contained 0.59-1.59% (w/v) solid matter (D. alata L.>D. batatas >D. nipponica>D. bulbifera). The mean concentrations of total polyphenols, total flavonoids, and total sugars in the different types of yam were 49.82 mg/g, 9.79 mg/g, and 173.81 mg/g, respectively. Analysis of DPPH radical-scavenging activity showed that D. alata L. Gyeongbuk No. 6 had a strong antioxidant capacity (IC50=$142.30{\mu}g/mL$), whereas the other yams showed reduced levels of activity (IC50=371-$486{\mu}g/mL$). D. alata L. Gyeongbuk No. 6 showed a strong antithrombin activity against human thrombin. Upon treatment with a D. alata methanol extract (1.5 mg/mL), thrombin time was increased 7.35-fold compared with that when methanol alone was used. In an antimicrobial activity assay, the D. nipponica extract showed moderate antibacterial activity against Bacillus subtilis, Staphylococcus aureus, Proteus vulgaris, and Salmonella typhimurium. Our results indicate that different varieties of Dioscorea spp., including D. batatas, have useful biochemical attributes, including antioxidant, antithrombin, and antibacterial activities.

Live Load Distribution in Prestressed Concrete I-Girder Bridges (I형 프리스트레스트 콘크리트 거더교의 활하중 분배)

  • Lee, Hwan-Woo;Kim, Kwang-Yang
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.21 no.4
    • /
    • pp.325-334
    • /
    • 2008
  • The standard prestressed concrete I-girder bridge (PSC I-girder bridge) is one of the most prevalent types for small and medium bridges in Korea. When determining the member forces in a section to assess the safety of girder in this type of bridge, the general practice is to use the simplified practical equations or the live load distribution factors proposed in design standards rather than the precise analysis through the finite element method or so. Meanwhile, the live load distribution factors currently used in Korean design practice are just a reflection of overseas research results or design standards without alterations. Therefore, it is necessary to develop an equation of the live load distribution factors fit for the design conditions of Korea, considering the standardized section of standard PSC I-girder bridges and the design strength of concrete. In this study, to develop an equation of the live load distribution factors, a parametric analysis and sensitivity analysis were carried out on the parameters such as width of bridge, span length, girder spacing, width of traffic lane, etc. As a result, the major variables to determine the size of distribution factors were girder spacing, overhang length and span length in case of external girders. For internal adjacent girders, the determinant factors were girder spacing, overhang length, span length and width of bridge. For internal girders, the factors were girder spacing, width of bridge and span length. Then, an equation of live load distribution factors was developed through the multiple linear regression analysis on the results of parametric analysis. When the actual practice engineers design a bridge with the equation of live load distribution factors developed here, they will determine the design of member forces ensuring the appropriate safety rate more easily. Moreover, in the preliminary design, this model is expected to save much time for the repetitive design to improve the structural efficiency of PSC I-girder bridges.

Isolation and Identification of Agarose-degrading Bacterium, Pseudoalteromonas sp. GNUM08122 (아가로오스 분해세균인 Pseudoalteromonas sp. GNUM08122 분리 및 동정)

  • Kim, Yu-Na;Jeong, Yeon-Kyu;Kim, Mu-Chan;Kim, Sung-Bae;Chang, Yong-Keun;Chi, Won-Jae;Hong, Soon-Kwang;Kim, Chang-Joon
    • Microbiology and Biotechnology Letters
    • /
    • v.40 no.1
    • /
    • pp.1-9
    • /
    • 2012
  • This study's aim was to isolate microorganisms producing agarase with a high activity, with possible applications in improving the performance of the pretreatment processes for bioethanol production. Marine algaes were collected from the south coast of Korea, from which three kinds of microorganisms were isolated. After a 4-day culture of these strains at $25^{\circ}C$, crude enzymes were obtained from culture supernatant or cell-free extract by ammonium sulfate precipitation and membrane dialysis. Agarase activity was observed in these crude enzymes. Notably higher specific activity was observed in the crude enzyme obtained from the culture supernatant rather than that from the cell-free extract. This indicates that a secreted enzyme has a much greater activity than a cellular enzyme. Crude enzymes from the GNUM08122 strain were inferred to have ${\alpha}$-agarase activity because release of p-nitrophenol was observed, possibly due to the cleavage of p-nitrophenyl-${\alpha}$-D-galactopyranoside. The 16S rRNA sequence of GNUM08122 showed a close relationship to Pseudoalteromonas issachenkonii KMM 3549 (99.8%) and Pseudoalteromonas tetraodonis IMA 14160 (99.7%), which led us to assign it to the genus Pseudoalteromonas. Biochemical and physiological study revealed that this strain can grow well at $40^{\circ}C$ under a wide range of pH (pH 4~8) in high-salt conditions (10% NaCl).

Development of an IoT Device for Detecting Escherichia coli from Various Agri-Foods and Production Environments (IoT 적용 대장균 검출기 개발과 농식품 및 생산환경에 적용)

  • Nguyen, Bao Hung;Chu, Hyeonjin;Kim, Won-Il;Hwang, Injun;Kim, Hyun-Ju;Kim, Hwangyong;Ryu, Kyoungyul;Kim, Se-Ri
    • Journal of Food Hygiene and Safety
    • /
    • v.34 no.6
    • /
    • pp.542-550
    • /
    • 2019
  • To detect Escherichia coli from agri-food and production environments, a device based on IoT (internet of things) technology that can check test results in real time on a mobile phone has been developed. The efficiency of the developed device, which combines an incubator equipped with a UV lamp, a high-resolution camera and software to detect E. coli in the field, was evaluated by measuring the device's temperature, detection limit, and detection time. The device showed a difference between its programmed temperature setting and actual temperature of about 1.0℃. In a detection limit test performed with a single-colony inoculation, a color change to yellow and a florescent signal were detected after 12 and 15 h incubations, respectively. The incubation time also decreased along with increasing bacteria levels. When applying the developed method and device to various samples, including utensils, gloves, irrigation water, seeds, and vegetables, detection rates of E. coli using the device were higher than those of the Korean Food Code method. These results show that the developed protocol and device can efficiently detect E. coli from agri-food production environments and vegetables.

Characterization of Filamentous Cyanobacteria Encapsulated in Alginate Microcapsules (알긴산염 마이크로캡슐 내부에 동결보존된 사상체 남세균의 특성 연구)

  • Park, Mirye;Kim, Z-Hun;Nam, Seung Won;Lee, Sang Deuk;Yun, Suk Min;Kwon, Dae Ryul;Lee, Chang Soo
    • Microbiology and Biotechnology Letters
    • /
    • v.48 no.2
    • /
    • pp.205-214
    • /
    • 2020
  • Cyanobacteria are microorganisms which have important roles in the nitrogen cycle due to their ability to fix nitrogen in water and soil ecosystems. They also produce valuable materials that may be used in various industries. However, some species of cyanobacteria may limit the use of water resources by causing harmful algal blooms in water ecosystems. Many culture collection depositories provide cyanobacterial strains for research, but their systematic preservation is not well-developed in Korea. In this study, we developed a method for the cryopreservation of the cyanobacteria Trichormus variabilis (syn. Anabaena variabilis), using alginate microcapsules. Two approaches were used for the experiments and their outputs were compared. One of the methods involved the cryopreservation of cells using only a cryoprotectant and the other used the cryoprotectant within microcapsules. After cryopreservation for 35 days, cells preserved with both methods were successfully regenerated from the initial 1.0 × 105 cells/ml to a final concentration of 6.7 × 106 cells/ml and 1.1 × 107 cells/ml. Irregular T. variabilis shapes were found after 14 days of regeneration. T. variabilis internal structures were observed by transmission electron microscopy (TEM), revealing that lipid droplets were reduced after cryopreservation. The expression of the mreB gene, known to be related to cell morphology, was downregulated (54.7%) after cryopreservation. Cryopreservation using cryoprotectant alone or with microcapsules is expected to be applicable to other filamentous cyanobacteria in the future.

A Comparative Study on the Effective Deep Learning for Fingerprint Recognition with Scar and Wrinkle (상처와 주름이 있는 지문 판별에 효율적인 심층 학습 비교연구)

  • Kim, JunSeob;Rim, BeanBonyka;Sung, Nak-Jun;Hong, Min
    • Journal of Internet Computing and Services
    • /
    • v.21 no.4
    • /
    • pp.17-23
    • /
    • 2020
  • Biometric information indicating measurement items related to human characteristics has attracted great attention as security technology with high reliability since there is no fear of theft or loss. Among these biometric information, fingerprints are mainly used in fields such as identity verification and identification. If there is a problem such as a wound, wrinkle, or moisture that is difficult to authenticate to the fingerprint image when identifying the identity, the fingerprint expert can identify the problem with the fingerprint directly through the preprocessing step, and apply the image processing algorithm appropriate to the problem. Solve the problem. In this case, by implementing artificial intelligence software that distinguishes fingerprint images with cuts and wrinkles on the fingerprint, it is easy to check whether there are cuts or wrinkles, and by selecting an appropriate algorithm, the fingerprint image can be easily improved. In this study, we developed a total of 17,080 fingerprint databases by acquiring all finger prints of 1,010 students from the Royal University of Cambodia, 600 Sokoto open data sets, and 98 Korean students. In order to determine if there are any injuries or wrinkles in the built database, criteria were established, and the data were validated by experts. The training and test datasets consisted of Cambodian data and Sokoto data, and the ratio was set to 8: 2. The data of 98 Korean students were set up as a validation data set. Using the constructed data set, five CNN-based architectures such as Classic CNN, AlexNet, VGG-16, Resnet50, and Yolo v3 were implemented. A study was conducted to find the model that performed best on the readings. Among the five architectures, ResNet50 showed the best performance with 81.51%.

The Plan of Dose Reduction by Measuring and Evaluating Occupationally Exposed Dose in vivo Tests of Nuclear Medicine (핵의학 체내검사 업무 단계 별 피폭선량 측정 및 분석을 통한 피폭선량 감소 방안)

  • Kil, Sang-Hyeong;Lim, Yeong-Hyeon;Park, Kwang-Youl;Jo, Kyung-Nam;Kim, Jung-Hun;Oh, Ji-Eun;Lee, Sang-Hyup;Lee, Su-Jung;Jun, Ji-Tak;Jung, Eui-Ho
    • The Korean Journal of Nuclear Medicine Technology
    • /
    • v.14 no.2
    • /
    • pp.26-32
    • /
    • 2010
  • Purpose: It is to find the way to minimize occupationally exposed dose for workers in vivo tests in each working stage within the range of the working environment which does not ruin the examination and the performance efficiency. Materials and Methods: The process of the nuclear tests in vivo using a radioactive isotope consists of radioisotope distribution, a radioisotope injection ($^{99m}Tc$, $^{18}F$-FDG), and scanning and guiding patients. Using a measuring instrument of RadEye-G10 gamma survey meter (Thermo SCIENTIFIC), the exposure doses in each working stage are measured and evaluated. Before the radioisotope injection the patients are explained about the examination and educated about matters that require attention. It is to reduce the meeting time with the patients. In addition, workers are also educated about the outside exposure and have to put on the protected devices. When the radioisotope is injected to the patients the exposure doses are measured due to whether they are in the protected devices or not. It is also measured due to whether there are the explanation about the examination and the education about matters that require attention or not. The total exposure dose is visualized into the graph in using Microsoft office excel 2007. The difference of this doses are analyzed by wilcoxon signed ranks test in using SPSS (statistical package for the social science) program 12.0. In this case of p<0.01, this study is reliable in the statistics. Results: It was reliable in the statistics that the exposure dose of injecting $^{99m}Tc$-DPD 20 mCi in wearing the protected devices showed 88% smaller than the dose of injecting it without the protected devices. However, it was not reliable in the statistics that the exposure dose of injecting $^{18}F$-FDG 10 mCi with wearing protected devices had 26% decrease than without them. Training before injecting $^{99m}Tc$-DPD 20 mCi to patient made the exposure dose drop to 63% comparing with training after the injection. The dose of training before injecting $^{18}F$-FDG 10 mCi had 52% less then the training after the injection. Both of them were reliable in the statistics. Conclusion: In the examination of using the radioisotope $^{99m}Tc$, wearing the protected devices are more effective to reduce the exposure dose than without wearing them. In the case of using $^{18}F$-FDG, reducing meeting time with patients is more effective to drop the exposure dose. Therefore if we try to protect workers from radioactivity according to each radioisotope characteristic it could be more effective and active radiation shield from radioactivity.

  • PDF

Pilot-scale Applications of a Well-type Reactive Barrier using Autotrophic Sulfur-oxidizers for Nitrate Removal (독립영양 황탈질 미생물을 이용한 관정형 반응벽체의 현장적용성 연구)

  • Lee, Byung-Sun;Um, Jae-Yeon;Lee, Kyu-Yeon;Moon, Hee-Sun;Kim, Yang-Bin;Woo, Nam-C.;Lee, Jong-Min;Nam, Kyoung-Phile
    • Journal of Soil and Groundwater Environment
    • /
    • v.14 no.3
    • /
    • pp.40-46
    • /
    • 2009
  • The applicability of a well-type autotrophic sulfur-oxidizing reactive barrier (L $\times$ W $\times$ D = $3m\;{\times}\;4\;m\;{\times}\;2\;m$) as a long-term treatment option for nitrate removal in groundwater was evaluated. Pilot-scale (L $\times$ W $\times$ D = $8m\;{\times}\;4\;m\;{\times}\;2\;m$) flow-tank experiments were conducted to examine remedial efficacy of the well-type reactive barrier. A total of 80 kg sulfur granules as an electron donor and Thiobacillus denitrificans as an active bacterial species were prepared. Thiobacillus denitrificans was successfully colonized on the surface of the sulfur granules and the microflora transformed nitrate with removal efficiency of ~12% (0.07 mM) for 11 days, ~24% (1.3 mM) for 18 days, ~45% (2.4 mM) for 32 days, and ~52% (2.8 mM) for 60 days. Sulfur granules attached to Thiobacillus denitrificans were used to construct the well-type reactive barrier comprising three discrete barriers installed at 1-m interval downstream. Average initial nitrate concentrations were 181 mg/L for the first 28 days and 281 mg/L for the next 14 days. For the 181 mg/L (2.9 mM) plume, nitrate concentrations decreased by ~2% (0.06 mM), ~9% (0.27 mM), and ~15% (0.44 mM) after $1^{st}$, $2^{nd}$, and $3^{rd}$ barriers, respectively. For the 281 mg/L (4.5 mM) plume, nitrate concentrations decreased by ~1% (0.02 mM), ~6% (0.27 mM), and ~8% (0.37 mM) after $1^{st}$, $2^{nd}$, and $3^{rd}$ barriers, respectively. Nitrate plume was flowed through the flow-tank for 49 days by supplying $1.24\;m^3/d$ of nitrate solution. During nitrate treatment, flow velocity (0.44 m/d), pH (6.7 to 8.3), and DO (0.9~2.8 mg/L) showed little variations. Incomplete destruction of nitrate plume was attributed to the lack of retention time, rarely transverse dispersion, and inhibiting the activity of denitrification enzymes caused by relatively high DO concentrations. For field applications, it should be considered increments of retention time, modification of well placements, and intrinsic DO concentration.

Studies on the Occurrence of Upland Weeds and the Competition with Soybeans (전지(田地)와 콩밭에 있어서 잡초(雜草)의 발생(發生) 및 경합(競合)에 관한 조사(調査) 연구(硏究))

  • Lee, Key-Hong;Lee, Eun-Woong
    • Korean Journal of Weed Science
    • /
    • v.2 no.2
    • /
    • pp.75-113
    • /
    • 1982
  • Studies were carried out 1) to define the shape and size of sampling quadrat and its number of observations for weed experiments, 2) to characterize the growth and community of major summer weeds under upland condition and 3) to investigate the factors influencing competition between weeds and soybeans under weed-free and weedy conditions in early and late season cultures. No significant difference was noted among different shapes of quadrat (regular, rectangular, band, and circular) in the sampling efficiency of weeds. The results also suggested that the minimum size of quadrat was 0.25$m^2$ and the minimum number of replication was 2 times per plot. The major dominant weeds were about 10 species in the experimental field and the total number of weeds was in the range of 70 - 1,600 plants per $m^2$. Among the weeds Digitaria sanguinalis and Portulaca oleracea were the most dominant species. Growth amount and reproduction capability were also measured by weed species. Five different weed communities were identified in the field. The degree of dispersion by weed species and association among weeds were investigated. Intra-(within soybeans) and inter-specific (between soybeans and weeds) competition were studied in early and late season cultures of soybeans. The average yield of soybeans per plant was significantly decreased in both season cultures due to intra-specific competition as the planting density of soybeans increased, On the other hand, the average yield of soybeans per l0a was proportionally increased to the increase of planting density and the rate of its increase was more significant under weedy than weed-free condition. Most of the agronomic characteristics of soybeans were affected by weeds and its degree was greater in sparse planting than in dense planting and in early season than in late-season culture. Digitaria sanguinalis was the most competitive to soybeans in early season and both of Digitaria sanguinalis and Portulaca oleracea affected primarily the growth of soybeans in late season with about the same competitiveness. The occurrence of weeds was significantly decreased in early season and slightly decreased in late-season by dense planting of soybeans. The total growth amount of weeds was also considerably decreased by increase of soybean planting density both in early- and late-season cultures. The occurrence of Digitaria sanguinalis which was the most dominant in both seasons, and its growth amount was significantly decreased as the planting density of soybean was increased. On the other hand, the occurrence of Portulaca oleracea which was only dominant in late-season culture did not show significant response to the planting density of soybeans.

  • PDF

Prediction of fertilizer demands up to the year of 2,000 from agronomic view points - Review and Discussion - (농경학적(農耕學的) 입장(立場)에서 본 서기(西紀) 2,000년(年)까지의 비료수요(肥料需要) 전망(展望) - 종합고찰(綜合考察) -)

  • Hong, Chong-Woon;Shin, Yong-Hwa
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.9 no.3
    • /
    • pp.211-220
    • /
    • 1976
  • The objective of this paper is to summarize and disicuss the results of studies for the prediction of fertilizer demands up to the year of 2000, from the agromic biew points. 1. The approximated demands of fertilizers figured out from the view point of nutrient requirement and fertilizer efficiency of major crops are 1,162,000M/T (N;554,100 M/T, $P_2O_5$; 360,100 M/T and $K_2O$, 247,000 M/T) at 1980, 1,471,400 M/T (N: 694,800 M/T, $P_2O_5$;465,400M/T and $K_2O$ ;311,200 M/T) at 1990 and 1,764,00 M/T (N;812,500 M/T, $P_2O_5$; 592,300 M/T and $K_2O$;359,200 M/T) at 2000${\cdots}{\cdots}$ (Approximation I) 2. Upon the basis of approximation on the yield levels of major crops per unit area and on the expansion of arable land, the demands of fertilizers at the years of 1980, 1990 and 2000 are predicted as 1,149,300 M/T (N;603,700 M/T $P_2O_5$; 305,500 M/T and $K_2O$, 240,100 M/T) 1,551,100 M/T(N:814,700M/T, $P_2O_5$;412,300 M/T and $K_2O$;324,00 M/T) and 2,253,800 M/T (N;1,183,800M/T, $P_2O_5$; 586,400M/T and $K_2O$, 470,900 M/T), respectively${\cdots}{\cdots}$(Approximation II) 3. When the recent relationships between the increases in yeid of major crops and the amounts of fertilizers for those crops per unit area are brought into consideration for the estimation of future demands of fertilizers, the predicted demands at the years of 1980, 1990 and 2000 are 1,287.600 M/T (N;677,100 M/T, $P_2O_5$; 342,000 M/T, and $K_2O$;268,500 M/T), 2,085,600M/T (N;1,096,700 M/T, $P_2O_5$;533,900 M/T, and $K_2O$;435,000 M/T and 3,380,600 M/T (N;1,777,800M/T, $P_2O_5$;897,800M/T and $K_2O$;705,000M/T) respectively (Approximation III) 4. Approximation I will be closer estimate under such condition that only rice will maintain self suficiency and other food crops will be covered by domestic production by around 50 percent, which is not desirable situation. 5. When higher self suficiency leveles of major food crops are sought through the introduction of improved varieties and expansion of cropping area and arable land by increased land utilization and reclamation of hillside land and tidal land, the Approximations II and III will become close to reality, If improved fertilizers and improved method of fertilizer applications are widely applied at the farmers fields to increase the fertilizer efficiency the former will be closer figure, if not, the latter may be better estimates.

  • PDF