• Title/Summary/Keyword: Limiting factors

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Peltier Heating-Assisted Low Temperature Plasma Ionization for Ambient Mass Spectrometry

  • Lee, Hyoung Jun;Oh, Ji-Seon;Heo, Sung Woo;Moon, Jeong Hee;Kim, Jeong-hoon;Park, Sung Goo;Park, Byoung Chul;Kweon, Gi Ryang;Yim, Yong-Hyeon
    • Mass Spectrometry Letters
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    • v.6 no.3
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    • pp.71-74
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    • 2015
  • Low temperature plasma (LTP) ionization mass spectrometry (MS) is one of the widely used ambient analysis methods which allows soft-ionization and rapid analysis of samples in ambient condition with minimal or no sample preparation. One of the major advantages of LTP MS is selective analysis of low-molecular weight, volatile and low- to medium-polarity analytes in a sample. On the contrary, the selectivity for particular class of compound also implies its limitation in general analysis. One of the critical factors limiting LTP ionization efficiency is poor desorption of analytes with low volatility. In this study, a home-built LTP ionization source with Peltier heating sample stage was constructed to enhance desorption and ionization efficiencies of analytes in a sample and its performance was evaluated using standard mixture containing fatty acid ethyl esters (FAEEs). It was also used to reproduce the previous bacterial identification experiment using pattern-recognition for FAEEs. Our result indicates, however, that the bacterial differentiation from FAEE pattern recognition using LTP ionization MS still has many limitations.

Emerging Currents in Health and Medicine - A Socio-Cultural Critique of Their Discourses and Practices - (건강과 의학의 새로운 흐름 - 담론과 실천 방식에 관한 사회문화적 비평 -)

  • 이종찬
    • Health Policy and Management
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    • v.10 no.4
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    • pp.1-19
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    • 2000
  • We have witnessed several kinds of new discourses and practices in health and medicine since the 1970s, such as popular concerns with alternative or complementary medicine, inordinate attention to the promotion of 'healthy' living, rapid resurrection of traditional medicine and ecological management of health. Four structural and situational factors are discussed to underlie these new trends:(i) as 'crisis' in health care of the 1970s was translated into health care reform of the 1980s backed up by neo-liberal political philosophy, the state responsibility for nation's health is being transferred to the individual ;(ii) it resulted from the limits of biomedical paradigm in dealing with chronic diseases;(iii) medico-scientific knowledge of disease is transformed into the subjective discourses and technologies of health in postmodern society ; and (iv) it is deeply associated with the considerable increase in environmental risk perception of health and disease. There are some inherent countervailing forces in these new discourses and practices. First, while they derive from lifestyle-oriented behavioral change, medicalization of life and death is still consolidated in the new trends. Second, inasmuch as new tides are reliant upon science, they. are likely to be remote from techne that means not the practical application of theoretical knowing but a special form of practical knowing. Third, as new discourses and activities accomplished'in the name of health'increasingly occupy important strategies in forming the self-identity, they serve as moral apparatus which involves prescriptions about how we should live our lives and conduct our bodies, both individually and collectively. Therefore, two points are suggested to consider seriously whether these streams will succeed in improving the‘healthy’living of all the people. Instead of limiting tile perspective to medicine, healing and health care, a new matrix that interweave welfare, ecology and labor along with them is timely needed for enhancing the health for all. In addition, as the World Health Report fm strongly shows, inequality in health heavily depends upon socio-economic development of a society, and it is not the richest countries that have the best health status, but those that have the smallest income differences between rich and poor.

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Research on Consumer Protection of Carrier Billing Services (통신과금서비스 소비자 보호 방안 연구)

  • Yoo, Soon-Duck;Kim, Jong-Ihl
    • Journal of Digital Convergence
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    • v.13 no.3
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    • pp.1-10
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    • 2015
  • Carrier billing services market is growing according to the technical development. This study investigated the limiting factor in carrier billing services and suggested the improvement factor for it using the Delphi Method. The amount money to use in carrier billing charges should be provided in their credit based and the accumulated payment using a text message is displayed and also telecommunications carriers and carrier billing firms are the least responsible for consumer harm. It also provides administrative responsibility for communications carriers and billing services company for non recognition and payment. The service provider to prove negligence not proven by consumer and telecommunications billing service delinquency rate is applied at a rate such as a credit card and it also should integrate retail payment and service fee. This study will contribute to the communication billing services market growth through improved communication billing service. Further research is needed to continue the study of the factors that emerged from communication and billing services due to emerging technologies and services.

Identification of the Age of Fresh Ginseng Root According to Number of Stem Vestiges in Rhizome (경흔적 수에 의한 수삼의 연근판별)

  • Lee, Jang-Ho;Ahn, In-Ok;Kim, Young-Chang;Bang, Kyong-Hwan;Hyun, Dong-Yun;Lee, Sung-Sik
    • Journal of Ginseng Research
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    • v.31 no.3
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    • pp.142-146
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    • 2007
  • This experiment was conducted to find identification of ginseng root's age using the number of stem vestiges in rhizome. The number of stem vestiges in rhizome is a useful key to confirm the age of ginseng root as follow : 4-year-old root has two, 5-year-old root has three, 6-year-old root has four. The distribution of stem vestiges in rhizome each year root are as follow : 2 stem vestiges in 4-year-old root is 89.5%, 3 stem vestiges in 5-year-old root is 79.7%, 4 stem vestiges in 6-year-old root is 46.3%. However, the limiting factors of identification of ginseng root's age using the number of stem vestiges in rhizome is appearance of multi-stem per plant and appearance of destroyed stem vestige in rhizome. The ratio of appearance of multi-stem per plant and destroyed stem vestige in rhizome are increased according to root age.

A Study on the Seismic Resistance of Fill-dams by Newmark-type Deformation Analysis (Newmark 기반 변형해석에 의한 필댐의 내진저항성 연구)

  • Park, Dong Soon
    • Journal of the Earthquake Engineering Society of Korea
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    • v.18 no.4
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    • pp.161-170
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    • 2014
  • Newmark-type deformation analysis has rarely been done in Korea due to the popularity of simple pseudo-static limit equilibrium analysis and detailed time-history FE/FD dynamic analysis. However, the Korean seismic dam design code updated in 2011 prescribes Newmark-type deformation analysis as a major dynamic analysis method for the seismic evaluation of fill dams. In addition, a design PGA for dynamic analysis is significantly increased in the code. This paper aims to study the seismic evaluation of four existing large fill dams through advanced FEM/Newmark-type deformation analyses for the artificial earthquake time histories with the design PGA of 0.22g. Dynamic soil properties obtained from in-situ geo-physical surveys are applied as input parameters. For the FEM/Newmark analyses, sensitivity analyses are performed to study the effects of input PGA and $G_{max}$ of shell zone on the Newmark deformation. As a result, in terms of deformation, four fill dams are proved to be reasonably safe under the PGA of 0.22g with yield coefficients of 0.136 to 0.187, which are highly resistant for extreme events. Sensitivity analysis as a function of PGA shows that $PGA_{30cm}$ (a limiting PGA to cause the 30 cm of Newmark permanent displacement on the critical slip surface) is a good indicator for seismic safety check. CFRD shows a higher seismic resistance than ECRD. Another sensitivity analysis shows that $G_{max}$ per depth does not significantly affect the site response characteristics, however lower $G_{max}$ profile causes larger Newmark deformation. Through this study, it is proved that the amplification of ground motion within the sliding mass and the location of critical slip surface are the dominant factors governing permanent displacements.

BIOLOGICAL CONTROL OF GINSENG ROOT ROTS WITH SOIL AMENDMENTS

  • Chung Hoo Sup;Kim Choong Hoe
    • Proceedings of the Ginseng society Conference
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    • 1978.09a
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    • pp.67-74
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    • 1978
  • The phenomenon of 'soil sickness' is one of the most important limiting factors for ginseng(Panax ginseng) production in Korea. The principal cause is known to be due to the root rots caused by Cylindrocarpon destructans and Fusarium solani. Attempts were made to control the root rots with non-polluting cultural methods or soil amendments. Among the nine soil amendments tested, crab shell, cow bone and pig feces were selected for further testing. Each of the three amendments increased the populations or various actinomycetes in the range of 10-25 times over that of non-amended soil, whereas the population of C. destructans was reduced to about $50-70\%$ as compared with the control. Five isolates of Streptomyces with clear zones on chitin-agar medium were selected and then tested for their antagonistic effects on C. destructans. When anyone of the five isolates of Streptomyces and C. destructans was grown together in a modified peptone broth, growth of the latter was highly inhibited. When three levels of crab shell, cow bone, or pig feces were used to amend potted soil infested with C. destruetans, the root rot ratings of ginseng seedlings were reduced to less than one half in all the treatments as compared to the control. In another similar experiment, crab shell and cow bone amendments resulted in almost complete control of the seedling root rots in soil infested with C. destructans or F. solani. In conclusion, biological control with soil amendments of ginseng root rots caused by C. destructans and F. solani was successful. Further basic studies should be pursued using soil amendments for better control. In addition, field experiments are needed to complement the soil amendment control measures in an integrated pest control program.

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Expression of Arabidopsis thaliana SIK (Stress Inducible Kinase) Gene in a Potato Cultivar (Solanum tuberosum L. 'Taedong Valley')

  • Yoon Jung-Ha;Fang Yi-Lan;Park Eung-Jun;Kim Hye-Jin;Na Yun-Jeong;Lee Dong-Hee;Yang Deok-Chun;Lim Hak-Tae
    • Plant Resources
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    • v.8 no.3
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    • pp.202-208
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    • 2005
  • Osmotic stress is one of major limiting factors in crop production. In particular, seasonal drought often causes the secondary disease in the field, resulting in severe reduction in both quality and productivity. Recent efforts have revealed that many genes encoding protein kinases play important roles in osmotic stress signal transduction pathways. Previously, the AtSIK (Arabidopsis thaliana Stress Inducible Kinase) mutants have shown to enhance tolerance to abiotic stresses, accompanying with higher expression of abiotic stress-related genes than did the wild-type plants. In this study, we have transformed potato (cv. Taedong Valley) with the AtSIK expression cassette. Both PCR and RT-PCR using AtSIK-specific primers showed stable integration and expression of the AtSIK gene in individual transgenic lines, respectively. Foliar application of herbicide ($Basta^{(R)}$) at commercial application rate (0.3% (v/v)) revealed another evidence of stable gene introduction of T-DNA which includes the bar gene for herbicide resistance. Overexpression of the AtSIK gene under dual CaMV35S promoter increased sensitivity to salt stress (300 mM NaCl), which was demonstrated by the reduction rate of chlorophyll contents in leaves of transgenic potato lines. These results suggest that possible increase of osmotic tolerance in potato plants may be achieved by antisense expression of AtSIK gene.

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Physiological Response of Panax Ginseng to Tcmpcrature II. Leaf physiology, soil temperature, air temperature, growth of pathogene (인삼의 온도에 대한 생리반응 II. 엽의 생리, 지온, 기온, 병환의 생육)

  • Park, Hoon
    • Journal of Ginseng Research
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    • v.4 no.1
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    • pp.104-120
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    • 1980
  • The effects of temperature on transpiration, chlorophyll content, frequency and aperture of stomata, and leaf temperature of Panax ginseng were reviewed. Temperature changes of soil and air under spade roof were also reviewed. Growth responses of responses of ginseng plant at various temperature were assessed in relation to suseptibillity of ginseng plants. Reasonable management of ginseng fields was suggested based on the response of ginseng to various temperatures. Stomata frequency may be increased under high temperature during leaf$.$growing stage. Stomata aperture increased by high temperature but the increase of both frequency and aperture appears not enough for transpiration to overcome high temperature encountered during summer in most fields. Serial high temperature disorder, i.e high leaf temperature, chlorophyll loss, inhibition of photosynthesis, increased respiration and wilting might be alleviated by high humidity and abundant water supply to leaf. High air temperature which limits light transmission rate inside the shade roof, induces high soil temperature(optimum soil temperature 16∼18$^{\circ}C$) and both(especially the latter) are the principal factors to increase alternaria blight, anthracnose, early leaf fall, root rot and high missing rate of plant resulting in poor yield. High temperature disorder was lessen by abundant soil water(optimum 17∼21%) and could be decreased by lowering the content of availability of phosphorus and nitrogen in soil consequently resulting in less activity of microorganisms. Repeated plowing of fields during preparation seems to be effective for sterilization of pathogenic microoganisms by high soil temperature only on surface of soils. Low temperature damage appeared at thowing of soils and emergence stage of ginseng but reports were limited. Most limiting factor of yield appeared as physiological disorder and high pathogen activity due to high temperature during summer(about three months).

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Effects of Coffee Shop Brand Attributes and Price Fairness on the Purchasing Behavior - Focus on the Case of Coffee Shop A - (커피전문점의 브랜드 속성과 가격공정성이 구매행동에 미치는 영향 - A 커피전문점을 대상으로 -)

  • Choi, Mi Sun;Jung, Ju Hee;Kim, Ye Young
    • Journal of the Korean Society of Food Culture
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    • v.32 no.6
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    • pp.549-557
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    • 2017
  • As many companies are performing brand management as a marketing strategy to establish long-term relationships with their customers, consumers decide the actual purchasing behavior by understanding the brand attributes of the relevant company based on an evaluation standard of the products. This paper provides the basic data for improving the competitiveness of the coffee shop market continuously, and analyzes the influential relationships between each variable by limiting the brand attributes of the coffee shop and the price fairness factor that would be expected to affect the consumers' purchasing behavior as the cause variables. The results showed that the-out of brand attribute factors of the coffee shop, the brand awareness and perceived quality had significant effects on the price fairness while the influence of the shop image on the price fairness was not verified. In addition, all the brand awareness, shop image, and perceived quality had significant effects on the purchasing behavior while the statistical significance between price fairness and purchasing behavior was verified. The rationality of the price presented by the coffee shop could be judged depending on the quality perceived by the consumers. Similarly, once consumers classified the propriety of price and then perceived that a suitable price had been set up regarding the quality and service provided by the coffee shop, it was highly possible for them to include it in their actual purchasing behavior, despite the higher price than other brands'. Further research on the psychological variables affecting the purchasing behavior by securing more diverse consumers to understand their purchasing behavior for a wide range of research subjects and the generalization of research results, will provide useful data for establishing marketing measures necessary to form strong relationships between consumers and brand in the currently-saturated coffee shop market.

A study on the procedure and method for engineering comprehensive design for collaboration between engineering and design (공학과 디자인의 협업을 위한 공학 계열 종합설계의 수행절차와 방법 연구)

  • Huh, Won-Whoi
    • Journal of the Korea Convergence Society
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    • v.11 no.5
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    • pp.125-130
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    • 2020
  • Universities that hold engineering education accreditation emphasize the importance of design education. In particular, comprehensive design courses in the engineering field are designed to produce the result reflecting the functional and limiting factors of the design. Systematic design education is also important, but the application of multidisciplinary convergence education is very high in view of the comprehensive design curriculum as a creative education program. This study describes a case study of convergence of curriculum and engineering and design, focusing on the 2019 comprehensive engineering design subject of the researcher. For the collaboration between engineering and design, the process of developing students' ideas and applying them to actual results was presented as the procedures of planning and theme selection, content design, software design, presentation and evaluation. As a result, it is meaningful that the method of convergence between engineering and design was presented without focusing only on technology in the comprehensive design subject of engineering by applying a design that considers the user in producing the work.