• Korean Journal Plant Pathology
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• v.3 no.3
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• pp.203-209
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• 1987

The substances obtained from the leaf, stem and root of tobacco plants inoculated with avirulent and virulent isolates of Pseudomonas solanacearum were at R_f\;0.6$ and R_f\;0.9$ on TLC plate, respectively. Both substances showed antibacterial activities not only on P. solanacearum but also on Erwinia carotovora subsp. carotovora and Escherichia coli in vitro. However, the antibacterial substances were not detectable from the filtrate of the autoclaves tobacco sap medium, in which the avirulent or virulent bacterium was cultured for 3 days. Peroxidase and poly phenoloxidase activities and their isozyme patterns did not differ significantly between plants treated with the virulent and avirulent isolates, or between the susceptible cultivar BY 4 and the resistant cultivar NC 82. However, activities of the two enzymes were increased in leaves of the susceptible cultivar BY 4 treated with either the virulent or the avirulent isolate.

• Research in Plant Disease
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• v.24 no.1
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• pp.81-85
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• 2018

Chinese artichoke (Stachys sieboldii Miq.) belongs to herbaceous perennial plants of Labiatea and is cultivated as edible and medicinal crops in China, Japan and Korea. A Chinese artichoke plant showing virus-like symptoms was collected in Chungju, Korea. Plant sap of the sample was inoculated in Nicotiana tabacum cv. Xanthi-nc, Chenopodium quinoa and Chenopodium amaranticolor. Necrotic local lesions were observed in the inoculated leaves of N. tabacum cv. Xanthi-nc and C. amaranticolor, C. quinoa with systemic chlorotic spots and mosaic symptoms on the upper leaves. The disease reactions on indicator plants suggested that the collected Chinese artichoke sample was mixed-infected with different viruses. We detected three viruses by RT-PCR analysis using genus- and species-specific primer sets for Alfalfa mosaic virus (AMV), Cucumber mosaic virus (CMV) and Tobacco mosaic virus (TMV). This study is the first report of a mixed infection of three viruses in Chinese artichoke in Korea.

• Journal of Korean Society of Transportation
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• v.22 no.3 s.74
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• pp.95-105
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• 2004

The fundamental diagram is a important element in a variety of transportation studies. While various shapes of the fundamental diagram have been proposed and numerous debates on the best-fit fundamental diagram have been made, the reason why the fundamental diagram has many different shapes has not been well explained. This study introduces time sap as a key parameter to understand drivers' behavioral differences at different locations and traffic conditions, then relate to the shape of the fundamental diagram. From the freeway event detector data, it is shown that time gap follows a certain probabilistic distribution and its mean value varies along locations. It also turns out that drivers take different time gaps for different travel speeds. Three different types of time gap-speed diagrams are identified and matched to Greenberg, reversed-lambda, and inverted-V types of fundamental diagrams, respectively. This study explains the characteristics of fundamental diagrams using time gap as a microscopic variable and describes drivers' behavioral characteristics according to traffic and geometric conditions.

• Earthquakes and Structures
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• v.4 no.5
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• pp.451-470
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• 2013

It generally accepted that most building structures shall exhibit a nonlinear response when subjected to medium-high intensity earthquakes. It is currently known, however, that this phenomenon is not properly modelled in the majority of cases, especially at the design stage, where only simple linear methods have effectively been used. Recently, as a result of the exponential progress of computational tools, nonlinear modelling and analysis have gradually been brought to a more promising level. A wide range of modelling alternatives developed over the years is hence at the designer's disposal for the seismic design and assessment of engineering structures. The objective of the study presented herein is to test some of these models in an existing structure, and observe their performance in nonlinear static and dynamic analyses. This evaluation is done by the use of two of a known range of advanced computer programs: SAP2000 and SeismoStruct. The different models will focus on the element flexural mechanism with both lumped and distributed plasticity element models. In order to appraise the reliability and feasibility of each alternative, the programs capabilities and the amount of labour and time required for modelling and performing the analyses are also discussed. The results obtained show the difficulties that may be met, not only in performing nonlinear analyses, but also on their dependency on both the chosen nonlinear structural models and the adopted computer programs. It is then suggested that these procedures should only be used by experienced designers, provided that they are aware of these difficulties and with a critical stance towards the result of the analyses.

• Structural Engineering and Mechanics
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• v.64 no.5
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• pp.543-555
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• 2017

The non-linear behaviour of integral infilled frames (in which the infill and the frame are bonded together with help of various interface materials) is studied both experimentally and numerically. The experiments were carried out on one-sixth scale two-bay and three-storey reinforced concrete frames with and without infill against static cyclic loading. Three interface materials - cement mortar, cork and foam have been used in between the infill and the frame. The infill, interface and the frame are bonded together is called integral frame. The linear and non-linear behaviors of two dimensional bare frame and integral infilled frame have been studied numerically using the commercial finite element software SAP 2000. Linear finite element analysis has been carried out to quantify the effect of various interface materials on the infilled frames with various combinations of 21 cases and the results compared. The modified configuration that used all three interface materials offered better resistance above others. Therefore, the experiments were limited to this modified infilled frame case configuration, in addition to conventional (A1-integral infilled frame with cement mortar as interface) and bare frame (A0-No infill). The results have been compared with the numerical results done initially. It is found that stiffness of bare frame increased by infilling and the strength of modified frame increased by 20% compare to bare frame. The ductility ratio of modified infilled frame was 42% more than that of the conventional infilled frame. In general, the numerical result was found to be in good agreement with experimental results for initial crack load, ultimate load and deformed pattern of infill.

• Structural Engineering and Mechanics
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• v.64 no.5
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• pp.671-681
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• 2017

This study investigates the structural performance of 3D steel pipe rack suspended scaffolding systems. For the purpose, a standard full scale 3D steel pipe rack suspended scaffolding system considering two frames, two plane trusses, purlins and wooden floor is constructed in the laboratory. A developed load transmission system was placed in these experimental systems to distribute single loads to the center of a specific area in a step-by-step manner using a load jack. After each load increment, the displacements are measured by means of linear variable differential transducers placed in several critical points of the system. The tests are repeated for five different system conditions to determine the structural performance. The means of system conditions is the numbers of the tie bars which are used to connect plane trusses under level. Finite elements models of the 3D steel pipe rack suspended scaffolding systems considering different systems conditions are constituted using SAP2000 software to support the experimental tests and to use the models in future studies. Each of models including load transmission platform is analyzed under a single loading and the displacements are obtained. In addition, to calibrate the numerical models some uncertain parameters such as elasticity modulus of wooden floor and connection rigidity of purlins to plane trusses are assessed experimentally. The results of this work demonstrate that when increasing numbers of tie bars the displacement values are decreased. Also the results obtained from developed numerical models have harmony with those of experimental. In addition, the scaffolding system with two tie bars at the beginning and at the end of the plane truss has the optimum structural performance compared the results obtained for other scaffolding system conditions.

• The Journal of Society for e-Business Studies
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• v.9 no.2
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• pp.163-181
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• 2004

Recently, it is to increase rapidly in people who do a private business through Web service. So, many companies have been developing part of businesses using Web Services. The greatest interest of companies developing Web Services was that users were easily discovering and using information on theirs. So, companies have been taking interest in a standard that supports registrations of information on Web service and discoveries of a registered Web services. Therefore UDDI 3.0 standard of the registry for Web service standardized by OASIS is in the spotlight. But, because of the complexity of it, there are no implementations developed in the inside of the country yet. And a development activity of it is faint. In outside of the country, IBM, Microsoft and SAP has developed it, but they do not perfectly support a standard of UDDI 3.0. This Paper shows the development of the Registry System which supports perfectly a standard of UDDI 3.0.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.1B
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• pp.26-38
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• 2006

To construct seamless collaborative environments, what all participants intent should be delivered, and visual elements such gesture, facial expression, and ambiance should be shared with all participants. In this paper, we propose high-quality video service to support DV(digital video) and HDV(high-definition DV) based on Access Grid(AG) which is a prevalent collaborative system. The proposed service is designed for employing versatile media tools and codecs with SDP(session description protocol) and SAP(session announcement protocol). We also design network-adaptive video transmission module to mitigate the impact of network fluctuation. This periodically monitors multicast performance and controls frame rate on sender side considering network condition. The experimental results over the test bed show that proposed service enhances quality of AG video service and provides seamless high-quality video transport by mitigating the impact of network fluctuation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.4
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• pp.959-964
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• 2013

This study materialized the new module which enables to measure more precise data than the existing modules in order to examine the cardiac disorder critical patient's state by using Swan-Ganz Catheter. There was bolus type CO(Cardiac Output) module which measured CO by measuring the blood changes in temperature and recovery time by injecting cold sap into the heart in the past, but recently, it is not used in most of hospitals due to limit of difficulty of continuous monitoring for the patients. To overcome this limit, the continuous cardiac output measurement platform was materialized to enable the continuous monitoring for patients. The wasted cost issues because of introducing the expensive imported equipment to observe the critical patient`s state with abnormal cardiopulmonary function in the hospitals can be solved by using this new module, and the problem of existing modules should be supplemented for more accurate diagnosis by collecting more precise data.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.10
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• pp.6673-6678
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• 2015

Recently, the free form buildings are constructed frequently. Exterior and interior components of these buildings have the free cross-section and a curved shape. So, There are many usages of classical finite element having tapered section and free-style shape. Some general commercial applications like ETABS, SAP2000, MIDAS are usually used for the safety evaluation of the free form structures. However, there are some limits in the accuracy of structural analysis and the length of analysis time because a very complicated finite element mesh have to be used. Therefore, In this study, a pre and post program module was developed to take advantage of general 3-D curved beam element which has a free-style curved shape and mathematical backgrounds. Pre-post processing module has been developed in this study was developed to control the curvature of the curved members by the NURBS control points. As a result, fast geometric modeling than was possible commercial applications. In addition, realistic depiction of the shape and behavior patterns were possible because of the free-form building allows visual check of the free form.