• The Plant Pathology Journal
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• 제23권3호
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• pp.180-186
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• 2007

The biocontrol agent, Serratia plymuthica A21-4, has been developed for controlling pepper Phytophthora blight. Serratia plymuthica A21-4 strongly inhibits the mycelial growth, zoospore formation, and cyst germination of Phytophthora capsici in vitro. The application of a cell suspension of strain A21-4 to pepper plants in pot experiments and in greenhouse successfully controlled the disease. The bacteria produced a potent antifungal substance which was a key factor in the suppression of Phytophthora capsici. The most active chemical com-pound was isolated and purified by antifungal activity-guided fractionation. The chemical structure was identified as a chlorinated macrolide $(C_{23}H_{31}O_8Cl)$ by spectroscopic (UV, IR, MS, and NMR) data, and was named macrocyclic lactone A21-4. The active compound significantly inhibited the formation of zoosporangia and zoospore and germination of cyst of P. capsici at concentrations lower than $0.0625{\mu}g/ml$. The effective concentrations of the macrocyclic lactone A21-4 for $ED_{50}$ of mycelial growth inhibition were $0.25{\mu}g/ml,\;0.25{\mu}g/ml,\;0.30{\mu}g/ml \;and\;0.75{\mu}g/ml$ against P. capsici, Pythium ultimum, Sclerotinia sclerotiorum and Botrytis cinerea, respectively.

• International Journal of Industrial Entomology and Biomaterials
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• 제17권2호
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• pp.181-187
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• 2008

An entomopathogenic fungus, Paecilomyces fumosoroceus SFP-198 was isolated in Kyungbuk province, Korea and screened out for the control of Trialeurodes vaporariorum nymphs. It showed 72.5% efficacy against second instars of T. vaporariorum nymphs at 6 days after treatment in the laboratory. To select an active ingredient for the mass production and the formulation, SFP-198 culture products were compared based on their insecticidal activities against T. vaporariorum nymphs. Among them, conidia and blastospores showed much higher insecticidal activity than supernatants. Furthermore, SFP-198 conidia were more heat-resistant than blastospores, and also powder form of conidia was more stable than their suspension form. SFP-198 conidia showed high pathogenicity on not only T. vaporariorum but also Tetranychus urticae in the glasshouse. This result suggested that SFP-198 conidia can be used as a multi-targeting biological control agent against sucking agri- cultural pests, such as whiteflies and mites.

• 한국정밀공학회지
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• 제25권3호
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• pp.73-82
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• 2008

Recently MR CDC damper has been applied to semi-active suspension control system gradually. Compared to former hydraulic CDC damper, it has rapid time response performance as well as simple internal structure and wide range of damping force. In order to develop control logic algorithm which enables to take maximum advantage of unique characteristics of MR CDC damper, it is inevitable to perform a thorough investigation into its nonlinear performance. In many previous researches, MR fluid model was either simply assumed as Bingham Plastic, or a phenomenological model based on experiment was established instead to predict damping performance of MR CDC damper. These experimental flow model which is not based on flow analysis but intentionally built to fit damping characteristics, may lead to totally different results in case of different configuration or structure of MR CDC damper. In this study, a generalized flow formula from mathematical flow model of MR fluid for annular orifice is derived to analyze and predict damping characteristics when current is excited at piston valve.

• 로봇학회논문지
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• 제16권2호
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• pp.147-154
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• 2021

One of the most challenging issues when robots interact with the environment is to establish contact quickly and avoid high impact force at the same time. The proposed method implements the passive suspension system using the redundancy of the torque-controlled robot. Instead of utilizing the actual mechanical compliance, the distal joints near the end-effector are controlled to act as a virtual spring-damper system with low feedback gains. The proximal joints are precisely controlled to push the mid-link, which is defined as the boundary link between the proximal and distal joints, towards the environment with high feedback gains. Compared to the active compliance methods, the contact force measurements or estimates are not required for contact establishment and the control time delay problems do not occur correspondingly. The proposed method was applied to the landing foot control of the 12-DoF biped robot DYROS-RED in the simulations. In the results, the impact force during landing was significantly reduced at the same collision speed.

• 한국안전학회지
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• 제13권4호
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• pp.102-112
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• 1998

Shock absorber has a great influence on the performance of the vehicle(ride comfort, manipulation, noise, vibration, turning, stability). Therefore, in this study we consider theoretically about general damper, variable damping oil damper, the control of vehicle Characteristics for the suspension, and undesirable phenomenon. And we measured the vibration/noise characteristics of shock absorber for the real car experimentation, strain change, and noise characteristics of shock absorber using experimental equipment. The study of domestic company and research institute on the vehicle shock absorber is active, but that of basis is not. So we think that they should be accomplished actively. Therefore, this paper will develop theoretical system on the vibration/noise characteristics of shock absorber by theoretical consideration and experimental result analysis of dynamic characteristics of shock absorber that were accomplished in this study. Then we will use it as the optimistic design data for shock absorber development.

• 식물조직배양학회지
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• 제28권2호
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• pp.69-74
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• 2001

담배 (Nicotiana tabacum cv. BY4)의 이배체 식물과 약배양으로부터 유도된 반수체 식물의 잎절편을 사용하여 0.5mg/L 2.4-D 단독처리구에서 캘러스를 유도한 후, 2.0 mg/L 2.4-D, 1.0 mg/L Kinetin 및 0.1 mg/L BAP를 조합처리하여 계대배양을 하였다. 이배체에서는 2.0 mg/L 2.4-D와 1.0 mg/L 카이네틴의 조합처리구에서, 반수체는 2.0 mg/L2.4-D 와 0.1 mg/L BAP 조합처리구에서 세포증식이 양호하였으므로, 현탁배양도 동일조건에서 실시하였다. 세포괴를 균일하게 한 현탁배양세포를 p-Fluorophenylalanine (PFP)이 5~100 $\mu$M의 농도로 단독처리한 배지상에 2.0 mL씩 평판배양하여, 10, 20, 30일 후 PFP의 처리에 대한 저항성 colony를 조사하였다. 배양 30일 후 세포주의 생중량을 측정한 결과 PFP의 농도가 높아질수록 감소하였다. 선발된 캘러스는 이배체서 peroxidase의 활성도가 5 $\mu$M PFP 처리시에 가장 높았는데 100 $\mu$M PFP 처리까지는 대조구보다는 높았다. Catalase의 활성도는 5 $\mu$M PFP 처리시 가장 높았으나 100 $\mu$M PFP 처리시 가장 낮았다. 한편 반수체에서는 peroxidase와 catalase의 활성도는 50 $\mu$M PFP 처리시 가장 높게 나타나서 이배체와 반수체 사이에 효소활성의 차이는 뚜렷했다.

• 한국소음진동공학회논문집
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• 제18권3호
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• pp.299-306
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• 2008

The electromagnet in Maglev vehicles controls the voltage in its winding to maintain the air gap, a clearance between the electromagnet and guideway, within an allowable deviation, with strongly interacting with the flexible guideway. Thus, the vibration characteristics of guideway plays important role in dynamics of Maglev vehicles using electromagnet as an active suspension system. The effects of the guideway's vibrational characteristics on dynamics of the Maglev vehicle UTM-01 are analyzed. The coupled equations of motion of the vehicle/guideway with 3 DOFs are derived. Eigenvalues are calculated and frequency response analysis is also performed for a clear understanding of the dynamic characteristics due to guideway vibration characteristics. To verify the results, tests of the urban Mgalev vehicle UTM-02 are carried out. It is recommended that the natural frequency of the guideway be minimized and its damping ratio in the Maglev vehicle with a 5-states feedback control law as a levitation control law.

• The Plant Pathology Journal
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• 제29권2호
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• pp.174-181
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• 2013

The plant growth-promoting rhizobacterium Ochrobactrum lupini KUDC1013 elicited induced systemic resistance (ISR) in tobacco against soft rot disease caused by Pectobacterium carotovorum subsp. carotovorum. We investigated of its factors involved in ISR elicitation. To characterize the ISR determinants, KUDC1013 cell suspension, heat-treated cells, supernatant from a culture medium, crude bacterial lipopolysaccharide (LPS) and flagella were tested for their ISR activities. Both LPS and flagella from KUDC1013 were effective in ISR elicitation. Crude cell free supernatant elicited ISR and factors with the highest ISR activity were retained in the n-butanol fraction. Analysis of the ISR-active fraction revealed the metabolites, phenylacetic acid (PAA), 1-hexadecene and linoleic acid (LA), as elicitors of ISR. Treatment of tobacco with these compounds significantly decreased the soft rot disease symptoms. This is the first report on the ISR determinants by plant growth-promoting rhizobacteria (PGPR) KUDC1013 and identifying PAA, 1-hexadecene and LA as ISR-related compounds. This study shows that KUDC1013 has a great potential as biological control agent because of its multiple factors involved in induction of systemic resistance against phytopathogens.

• 한국중재학회지:중재연구
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• 제25권2호
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• pp.3-17
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• 2015

For many years commentators have requested more active regulation of attorney ethics in international arbitration. Gradual deterioration of ethical standards in international arbitration will bring disrepute and, once its reputation is lost, it could take decades to rebuild confidence. The first reason for increasing unethical behavior is that there is no ethical code generally applied to all lawyers participating in international arbitration. A second reason might be that nobody is actively regulating attorneys in international arbitration. The first step to solve this problem is that major arbitration institutions should cooperate to enact a uniform code of conduct to be generally applied to all attorneys representing parties in international arbitration. Recently, IBA and LCIA prepared guidelines on party representation in international arbitration, and the guidelines will help attorneys follow uniform standardsof ethics. However, this will not be sufficient. There should be a regulating body to monitor attorney ethics and take sanctions against unethical attorneys accordingly. Arbitrators, who can see unethical behavior by attorneys from the closest distance, are the most appropriate regulating force rather than courts of arbitration seat or an attorney's licensing country. Of course, arbitrators don't have powers to withdraw or suspend an attorney's license, but they have powers to control attorneys'behavior within arbitration proceedings such as an allocation of fees and costs, barring the assertion of claims or defenses, drawing adverse inferences, or precluding the submission of evidence or testimony. Furthermore, arbitrators should be provided with such obligation as active control of attorney ethics. Even arbitration institutions should participate by imposing on an attorney who is a repeat offender a suspension from appearing in future arbitrations. Unethical behavior will decrease through concerted actions among arbitrational institutions to introduce a uniform code of conduct and to empower arbitrators for more efficient regulation of attorney ethics.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVI)
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• pp.37-37
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• 2005

Human chorionic gonadotropin (hCG) is a heterodimeric glycoprotein hormone consisting of non-covalently linked two subunits, the ${\alpha}$ and ${\beta}$ subunit. It has been used as a infertility drug for ovulation to mimic luteinizing hormone $(LH).^{1)}$ A stable cell line was established by transfection of Rc/CMV-i-dhfr-hCG, expression vector containing hCG ${\alpha}-$ and ${\beta}-genes$, into dihydrofolate reductase-deficient CHO cells and subesquent methotrexate-mediated gene amplification. Anchorage-dependent CHO cells were adapted into a serum-free and/or animal component-free suspension medium through gradual serum weaning for the hCG production. The established cell line showed typical morphological characteristics and growth profile of CHO cells, and could produce FSH with passage-to-passage consistency. The high density perfusion culture of the CHO cells was carried out in Celligen Plus bioreactor equipped with a spin-filter as a internal cell retention device. The cell density reached up to $>1x10^{7}$ cells/ml in less than 7 days and a perfusion-control strategy based on cellular consumption rates of glucose was $established.^{2)}$ Biologically active recombinant hCG was purified by a series of chromatographic steps including anion exchange chromatography and hydrophobic interaction chromatography to homogeneity. The highly purified recombinant hCG was characterized for physicochemical, immunological and biological properties.