• Journal of Korean Tunnelling and Underground Space Association
• /
• v.19 no.3
• /
• pp.449-461
• /
• 2017

The uncertain existence and insufficient information of underground structures, such as pipe lines and cable tunnels, is causing many problems related to route plan, design, construction of new underground structures. The theoretical equations that is able to predict the location, size, and direction of underground structures through electric field analysis are suggested at the previous study (Ryu., 2015). Three field tests were performed for predicting the location, size, and direction of underground structures and the existence and size of sink-hole. Prediction results were reflected at the design and follow-up measures were performed.

• Journal of Microbiology and Biotechnology
• /
• v.9 no.5
• /
• pp.613-618
• /
• 1999

L-Proline-producing mutant strains were developed by exposing L-glutamic acid-producing bacteria to N-metyl-N-nitro-nitrosoguanidine and UV irradiation. A L-histidine auxotroph of Corynebacterium acetoacidophilum RYU3161(KCTC 0616BP), which was resistant to sulfaguanidine and proline analogs (DHP, AZC, TAC), was isolated. The activity of the mutant strain's $\gamma$-glutamyl kinase was 45% higher than that of the parent strain. The optimum level of L-histidine for production of L-proline was 0.16 g/l. In a 5-1 jar fermenter, the mutant strain produced L-proline at a high concentration (35 g/l) level within 48 h of cultivation.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.34 no.6
• /
• pp.455-461
• /
• 2012

Ankylosing spondylitis (AS) is a chronic autoimmune disease mainly involving the axial skeleton. The pathology of the disease is usually found at the sacroiliac joint, and half of the patients experience cervical spine invasion, but eventually, the whole spine is affected. The involvement of the temporomandibular joint (TMJ) in AS has not been investigated very well. A review of the literature revealed that there are only a few studies of TMJ involvement in AS that combined clinical and radiographic examinations. These studies show widely different results, ranging between 4% and 32%. We experienced Bilateral osseous ankylosis of the jaw treated by total alloplastic joint replacement in AS, and offer a case report.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.3 no.5
• /
• pp.507-526
• /
• 2009

Since SIP uses a text-based message format and is open to the public Internet, it provides a number of potential opportunities for Denial of Service (DoS) attacks in a similar manner to most Internet applications. In this paper, we propose an effective detection method for SIP flooding attacks in order to deal with the problems of conventional schemes. We derive the upper bound of the possible number of SIP messages, considering not only the network congestion status but also the different properties of individual SIP messages such as INVITE, BYE and CANCEL. The proposed method can be easily extended to detect flooding attacks by other SIP messages.

• Natural Product Sciences
• /
• v.8 no.3
• /
• pp.103-107
• /
• 2002

Four known sesquiterpenes, laurinterol (1), isolaurinterol (2), aplysinal (3) and aplysin (4) were isolated from the Korean red alga Laurencia okamurae off Cheju Island, Korea. Their structures were identified by comparison with the literature data. Compounds 1-4 showed potent cytotoxicity against A549, SK-OV-3, SKMEL-2, XF498, and HTl5 cell lines with $EC_{50}$ values ranging from 1.2 to 17.6 ${\mu}g/ml$.

• Journal of applied mathematics & informatics
• /
• v.30 no.1_2
• /
• pp.327-336
• /
• 2012

Let {$X_{ni}$, $i{\geq}1$, $n{\geq}1$} be an array of rowwise and pairwise negatively quadrant dependent random variables with mean zero, {$a_{ni}$, $i{\geq}1$, $n{\geq}1$} an array of weights and {$b_n$, $n{\geq}1$} an increasing sequence of positive integers. In this paper we consider some results concerning complete convergence of ${\sum}_{i=1}^{bn}a_{ni}X_{ni}$.

• Proceedings of the KSR Conference
• /
• 2010.06a
• /
• pp.1061-1067
• /
• 2010

In this paper, we propose a simulator for testing of the Navigation Control System(NCS) in Bimodal-tram. NCS uses values of all sorts of sensors installed in vehicle to decide current position, and to control speed and steering of vehicle to go to a next position. Major functions of simulator are input processing of the driver and generation of virtual sensor data and driving profile(navigation path, magnetic information), and the NCS function. Virtual sensor data is generated according to output data from the NCS, driving profile and input processing of the driver, and monitoring systems is operated separatedly to confirm of NCS operation. This paper discusses about the implementation of the simulator, and analyzes and evaluates the simulation results.

• Journal of Mechanical Science and Technology
• /
• v.18 no.12
• /
• pp.2148-2157
• /
• 2004

The paper deals with the vibration and dynamic stability of cantilevered pipes conveying fluid on elastic foundations. The relationship between the eigenvalue branches and corresponding unstable modes associated with the flutter of the pipe is thoroughly investigated. Governing equations of motion are derived from the extended Hamilton's principle, and a numerical scheme using finite element methods is applied to obtain the discretized equations. The critical flow velocity and stability maps of the pipe are obtained for various elastic foundation parameters, mass ratios of the pipe, and structural damping coefficients. Especially critical mass ratios, at which the transference of the eigenvalue branches related to flutter takes place, are precisely determined. Finally, the flutter configuration of the pipe at the critical flow velocities is drawn graphically at every twelfth period to define the order of the quasi-mode of flutter configuration.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2002.11a
• /
• pp.322-325
• /
• 2002

In this study, dielectric and piezoelectric properties of PSN-PZT Ceramic were investigated as a function of PNW substitution. With the increase of PNW substitution, teragonality, Curie temperature and mechanical quality factor were decreased but grain size and electromechanical coupling factor(kp) was gradully increased. At 4 mol [%] PNW substitution. maximum kp of 0.567 was shown.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2002.11a
• /
• pp.280-283
• /
• 2002

In this study, the effects of $Nb_{2}O_{5}$ addition on microstructure and piezoelectric characteristics of PNW-PMN-PZT ceramics were investigated. As $Nb_{2}O_{5}$ addition amount is increased, grain size is gradully decreased. At 0.3wt%$Nb_{2}O_{5}$ addition composition ceramics, maximum density, tetragonality and piezoelectric characteristics were obtained.