• Title/Summary/Keyword: E-Resources

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Operating Practices and Satisfaction on e-Learning -Focused on Human Resources Nourishing Institutions in Busan- (이러닝 운영실태 및 만족도 조사 -부산지역 인력양성기관을 중심으로-)

  • Jung, Ju-Young;Park, Choel-Min
    • Journal of The Korean Association of Information Education
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    • v.11 no.1
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    • pp.49-57
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    • 2007
  • The purpose of this study is to investigate operating practices of human resources nourishing institutions and analyze the degree of satisfaction to the e-learning learners in Busan. This study adopted a questionnaire method in research of 70 human resources nourishing institutions and 758 e-learning learners in Busan area for empirical analysis. Techniques used in analyzing data was frequency analysis. SPSS for windows programs were applied in the analysis. The major findings of this study are as follows. First, it is found that there is a widespread affirmative perceptions in the fields of both operating practices and satisfaction on e-learning. Second, however, it is also found that more efforts needed to be made in some areas such as method for effective e-learning and the management of programs, and more concerns should be need to the age group of fifty-over. These groups are short of understanding and acceptance of e-learning environment.

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Change of Stream water Chemistry and Contribution of Subsurface Discharge in Forest Catchment during Storm Events (산림유역내 강우 발생시 계류수질변화와 지중유출수의 기여도)

  • Kim Su-Jin;Jeong Yongho;Kim Kyongha;Yoo Jaeyun;Jeong Changgi;Jun Jaehong
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.7 no.1
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    • pp.51-56
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    • 2005
  • To understand the chemical changes in the streamwater and contribution of subsurface discharge during the storm event, we analyzed electric conductivity (EC), anions, and cations in Gwangneung deciduous and coniferous forest catchment. The stream water samples were collected three times in 2004 by using an auto-sampler: September 7-9 (E040907-D and -C; where D and C indicate deciduous and coniferous forest catchment, respectively), September 11-13 (E040911-D and -C), and September 16-18 (E040916-D and -C). We found a negative relationship between discharge intensity and EC in streamwater. The E040911 and E040916 showed slack change of stream discharge in comparison to E040907 due to contribution of base flow recharged by much precipitation. Moreover, NO/sub 3//sup -/ concentrations in E040911-C were highest, which may have resulted from forest management such as thinning in 2004. The relationship between pH and alkalinity in stream water showed that much of stream water have been recharged through subsurface. We conclude that subsurface discharge highly influences streamwater quality in a forested catchment, and the seperation of stream water discharge is therefore necessary to sustainable water management.

Biological Control of Strawberry Gray Mold Caused by Botrytis cinerea Using Bacillus licheniformis N1 Formulation

  • Kim, Hyun-Ju;Lee, Soo-Hee;Kim, Choul-Sung;Lim, Eun-Kyung;Choi, Ki-Hyuck;Kong, Hyun-Gi;Kim, Dae-Wook;Lee, Seon-Woo;Moon, Byung-Ju
    • Journal of Microbiology and Biotechnology
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    • v.17 no.3
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    • pp.438-444
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    • 2007
  • Bacillus licheniformis N1 is a biological control agent to control gray mold diseases caused by Botrytis cinerea. Various formulations of B. licheniformis N1 were generated and evaluated for the activity to control strawberry gray mold. The wettable powder type formulation N1E was selected in pot experiments with remarkable disease control activity on both strawberry leaves and flowers. The N1E formulation contained 400 g of com starch, 50 ml of olive oil, and 50 g of sucrose per a liter of bacterial fermentation culture. Optimum dilution of N1E to appropriately control the strawberry gray mold appeared to be 100-fold dilution in plastic house artificial infection experiments. The significant reduction of symptom development in the senescent leaves was apparent by the treatment of N1E at 100-fold dilution when N1E was applied before Bo. cinerea inoculation, but not after the inoculation. Both artificial infection experiments in a plastic house and natural infection experiments in the farm plastic house under production conditions revealed that the disease severity of gray mold on strawberry leaves and flowers was significantly reduced by N1E treatment. The disease control value of N1E on strawberry leaves was 81% under production conditions, as compared with the 61.5% conferred by a chemical fungicide, iprodione. This study suggests that our previously generated formulation of B. licheniformis N1 will be effective to control strawberry gray mold by its preventive activity.

Screening of Natural Plant Resources with Acetylcholinesterase Inhibition and Antioxidant Activity (천연 식물자원으로부터 Acetylcholinesterase 저해 및 항산화 활성 탐색)

  • Kim, Dae-Ik;Lee, Sung-Hyeon;Hur, Eun-Young;Cho, Soo-Muk;Park, Hong-Ju
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.3
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    • pp.427-432
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    • 2005
  • This study was performed to investigate the effect of natural plant extracts on acetylcholinesterase (AChE) activity and the free radical scavenging activity. The methanolic extracts of plants were tested for AChE inhibitory activity using Ellman's colorimetric method in 96-welled microplates and antioxidant activity as the scavenging effect of 1, 1-diphenyl-2-picryl hydrazyl radical (DPPH). The results showed that AChE activities were inhibited (about 20-30%) in whole plant extract of Daucus carota var. sativa, Hypericum erectum and Fragaria yezoensis. AChE activities were inhibited (about 32-34%) in stems extract of Gingko biloba and leaves extract of Rhododendrondron yedoensa var. poukhanense. Fruit extract of Zanthoxylum schinifolium inhibited (about 18%) AChE activity. And the DPPH scavenging effects as antioxidant activity were similar to L-ascorbic acid in whole plant extract of Fragaria yezoensis and fruits extract of Comus officinalis.

Complete genome sequence of Escherichia coli K_EC180, a bacterium producing shiga-like toxin isolated from swine feces

  • Kim, Hyeri;Cho, Jae Hyoung;Cho, Jin Ho;Song, Minho;Shin, Hakdong;Kim, Sheena;Kim, Eun Sol;Kim, Hyeun Bum;Lee, Ju-Hoon
    • Journal of Animal Science and Technology
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    • v.63 no.2
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    • pp.461-464
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    • 2021
  • Escherichia coli normally colonizes the lower intestine of animals and humans, but some serotypes are foodborne pathogens. The Escherichia coli K_EC180 was isolated from swine feces that were collected from a weaner pig. In this genome announcement, E. coli K_EC180 was sequenced using PacBio RS II and Illumina NextSeq 500 platforms. The complete chromosome of E. coli K_EC180 is composed of one circular chromosome (5,017,281 bp) with 50.4% of guanine + cytosine (G + C) content, 4,935 of coding sequence (CDS), 88 of tRNA, and 22 of rRNA genes. The complete genome of E. coli K_EC180 contains the toxin genes such as shiga-like toxins (stxA and stxB).

Growth curve estimates for wither height, hip height, and body length of Hanwoo steers (Bos taurus coreanae)

  • Park, Hu-Rak;Eum, Seung-Hoon;Roh, Seung-Hee;Sun, Du-Won;Seo, Jakyeom;Cho, Seong-Keun;Lee, Jung-Gyu;Kim, Byeong-Woo
    • Korean Journal of Agricultural Science
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    • v.44 no.3
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    • pp.384-391
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    • 2017
  • Growth curves in Hanwoo steers were estimated by Gompertz, Von Bertalanffy, Logistic, and Brody nonlinear models using growth data collected by the Hanwoo Improvement Center from a total of 6,973 Hanwoo (Bos taurus coreanae) steers 6 to 24 months old that were born between 1996 and 2015. The data included three parameters: A, mature size of body measurement; b, growth ratio; and, k, intrinsic growth rate. Nonlinear regression equations for wither height according to Gompertz, Von Bertalanffy, Logistic, and Brody models were $Y_t=144.7e^{-0.5869e^{-0.00301t}}$, $Y_t=145.3(1-0.1816e^{-0.00284t})^3$, $Y_t=143.1(1+0.7356e^{-0.00352t})^{-1}$, and $Y_t=146.8(1+0.4700e^{-0.00249t})^1$, respectively, while those for hip height were $Y_t=144.5e^{-0.5549e^{-0.00312t}}$, $Y_t=145.0(1-0.1724e^{-0.00295t})^3$, $Y_t=143.1(1+0.6863e^{-0.00360t})^{-1}$, and $Y_t=146.2(1+0.4501e^{-0.00263t})^1$, respectively. Equations for body length $Y_t=174.1e^{-0.8342e^{-0.00289t}}$, $Y_t=175.8(1-0.2500e^{-0.00265t})^3$, $Y_t=170.0(1+1.1548e^{-0.00363t})^{-1}$, and $Y_t=180.3(1+0.6077e^{-0.00215t})^1$, respectively, for the same models. Among the four models, the Brody model resulted in the lowest mean square error, with mean square errors of 31.79, 30.57, and 42.13, respectively, for wither height, hip height, and body length. Also, an estimated birth wither height, birth hip height, and birth body length (77.98, 80.57, and 70.97 cm, respectively) were lower in the Brody model than in other models. An inflection point was not observed during the growth phase of Hanwoo steer according to the growth curves calculated using Gompertz, Von Bertalanffy, and Logistic models. Based on the results, we concluded that the regression equation using the Brody model was the most appropriate among the four growth models. To obtain more accurate parameters, however, using data from a wider production period (from birth to shipping) would be required, and the development of a suitable model for body conformation traits would be needed.

Improved Detection of Viable Escherichia coli O157:H7 in Milk by Using Reverse Transcriptase-PCR

  • Choi, Suk-Ho;Lee, Seung-Bae
    • Food Science of Animal Resources
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    • v.31 no.2
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    • pp.158-165
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    • 2011
  • A sensitive reverse transcriptase-PCR (RT-PCR) method to detect viable Escherichia coli O157:H7 in milk was established. The primer sets were designed based on the nucleotide sequences of the rfbE (per) and wbdN genes in the O157 antigen gene cluster of E. coli O157:H7. RT-PCR using five different primer sets yielded DNA with sizes of 655, 518, 450, and 149-bp, respectively. All five of the E. coli O157:H7 strains were detected by RT-PCR, but 11 other bacterial species were not. The sensitivity of RT-PCR was improved by adding yeast tRNA as a carrier to the crude RNA extract. The RT-PCR amplifying the 149-bp DNA fragment was the most sensitive for detecting E. coli O157:H7 and the most refractory to the bactericidal treatments. Heat treatment at $65^{\circ}C$ for 30 min was the least inhibitory of all bactericidal treatments. Treatment with RNase A strongly inhibited the RT-PCR of heated milk but not unheated milk. This study described RT-PCR methods that are specific and sensitive with a detection limit of 10 E. coli O157:H7 cells, and showed that pre-treating milk samples with RNase A improved the specificity to detect viable bacteria by RT-PCR.

RRSiM : Agent SiMulator(1) (ASiM : 에이전트 시뮬레이터(1))

  • Song, Byung-Kwen
    • Journal of the Korea Society for Simulation
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    • v.15 no.4
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    • pp.41-50
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    • 2006
  • The agent system for managing various equipments constituting communication networks is usually started to be developed after completing real resources or can be developed using network management platform independent from real resources. In this paper, we design real resource simulator which can perform in advance the function of real resources without real resources. The real resource simulator performs the role of automatically generating specific attribute value and informing it according to the specified random function. Moreover, in this paper, we design E-GDMO grammar in which the grammar for simulation is added to the existing GDMO grammar and its E-GDMO compiler to perform real resource simulator.

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자원가격 불확실성 하에 북미 독립계 E&P기업의 투자옵션 연구

  • Gwon, O-Jeong;Park, Eun-Cheon;Park, Ho-Jeong
    • Environmental and Resource Economics Review
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    • v.21 no.3
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    • pp.441-464
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    • 2012
  • As prices of energy resources such as oil and gas started to rise steadily in 2000, energy security has been one of the most important topics in the world. To secure more energy, most of countries which are highly dependent on imported energy resources try to occupy oversea oil or gas reserves, thereby intensifying competition for energy resources around world. Under this circumstance, we focus on independent E&P companies since they are relatively small size companies which are suitable for M&A. We analyze investment option values for these E&P companies using a real option model for depletable resources. Based on analytical model, empirical study is provided to examine rationality of investment for energy companies. The result shows sufficient profitability for independent E&P companies in both oil and gas projects in the North America during 2004 to 2008. In Particular, oil projects were more feasible than gas project due to lower price of gas and high volatility of gas price at that time.

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