• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.3
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• pp.241-247
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• 2011

Although intensive development continues on innovative sensor systems, there is still considerable uncertainty in deciding on the number of sensors required and their locations in order to obtain adequate information on structural behavior. This paper is concerned with the sensor locations on a beam-structure for prognostic structural health monitoring. The purpose of this study is to investigate how to determine optimal sensor placement(OSP) from the sensitivity information of a known failure mode. The sensitivity of the forced vibration response of a beam to the variation of stiffness due to a crack is calculated analytically and used to determine the optimal sensor locations for the specified failure mode. The results of this method compared with the results of different OSP methods. The results have shown that the proposed method on optimal sensor placement is very effective in structural health monitoring.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.71-71
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• 2012

To control luminescence emission property, a novel series of strong fluorescent fluorin-boron complexes were synthesized in higher yield. The resulting structural analysis was completed. Small molecules with a built-in fluorine-boron core structural architecture has been attracted considered attention as the key emissive elements due to the their good properties such as bipolar charge transport and high photo efficiency. Thus, new type of fluorine-boron(F-B) complexes are designed and prepared. Changing the substituent position on fluorophore ring provided a deep understanding on the relationship between structure and optical properties.

• Textile Coloration and Finishing
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• v.25 no.1
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• pp.1-6
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• 2013

Nowdays, the computational simulation of molecular energy potentials and the empirical evidence using electrochemical reduction/oxidation values are very significant factors to predict of molecule's energy potentials. The prepared chemosensor herein consists of spirolactam ring system in the structure, providing intra-structural change with metal cation binding. In this study, rhodamine 6G-Naphthaldehyde chemosensor was determined and compared with HOMO/LUMO energy levels by computational calculation and cyclic voltammogram method.

• Journal of Microbiology and Biotechnology
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• v.19 no.10
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• pp.1150-1152
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• 2009

Geraniol (1) is the biogenetic precursor of a number of monoterpenes. We tested various marine-derived microorganisms to determine their ability to biotransform 1. Only Hypocrea sp. was capable of transforming 1 into its oxidized derivative, 1,7-dihydroxy-3,7-dimethyl-(E)-oct-2-ene (2). The structure of the metabolite obtained was assigned on the basis of detailed spectroscopic data analyses.

• Proceedings of the KIEE Conference
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• 2007.10c
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• pp.160-162
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• 2007

Switched-reluctance motor(SRM) has advantages such as simple structure, low cost and so on compared with induction motor. This paper proposes a new sensorless method that is based on the impressed voltage pulse method to estimate rotor position. Current sensors detect the SRM currents in the unenergised phases and output the voltage. The rotor position can be inferred by the above calculations when the peak values exceed a fixed threshold value.

• Proceedings of the Korea Multimedia Society Conference
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• 2001.11a
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• pp.46-50
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• 2001

Adaptive signal processing is used to acoustic echo canceller. adaptive noise canceller and adaptive algorithm among adaptive algorithms is mainly used because the structure is simple and computa LMS algorithm has trade-off between the converge speed and the steady state error. In this paper, step-size of adaptive algorithm is varied with orthogonality Principles of optimal filter to get fasts though small steady state error. Time varying step-size is determined proportional to the maximum vector of LMS algorithm. As results of simulations, the adaptive algorithm with proposed time-v compared with conventional ones.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2005.11a
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• pp.154-157
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• 2005

MLRS is the weapon system which has been mass-produced since 2004. MLRS launch tube has developed and produced independently refer to the facilities and process condition of General Dynamics Co, USA. The purpose of this research is base establishment for the launch tube performance improvement and application of another weapon system. Research performed about material property, process condition, and structural property.

• Journal of Korean Neurosurgical Society
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• v.43 no.4
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• pp.198-200
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• 2008

Giant cavernous malformations (GCMs) occur very rarely and little has been reported about their clinical characteristics. The authors present a case of a 20-year-old woman with a GCM. She was referred due to two episodes of generalized seizure. Computed tomography and magnetic resonance image demonstrated a heterogeneous multi-cystic lesion of $7\times5\times5$ cm size in the left frontal lobe and basal ganglia, and enhancing vascular structure abutting medial portion of the mass. These fingings suggested a diagnosis of GCM accompanying venous angioma. After left frontal craniotomy, transcortical approach was done. Total removal was accomplished and the postoperative course was uneventful. GCMs do not seem differ clinically, surgically or histopathologically from small cavernous angiomas, but imaging appearance of GCMs may be variable. The clinical, radiological feature and management of GCMs are described based on pertinent literature review.

• Journal of the Korea Institute of Military Science and Technology
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• v.11 no.6
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• pp.90-101
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• 2008

Korean defense specifications are the technical criteria of military products and major factor of acquisition system. Weapon systems and acquisition technique have been advanced dramatically after 1990's, but Korean defense specification practice standard has stayed after early 1980's except embedded software. The current status of current Korean defense specification practice standard and trend of related design and acquisition techniques like M&S, SBA, and digital manufacturing have been reviewed. This paper suggests that transfer to product, IT oriented specification structure, adaptation of digital product model and reinforcement of engineering management systems to establish a development initiative of Korean defense specification practice standard.

• Microbiology and Biotechnology Letters
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• v.23 no.2
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• pp.170-177
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• 1995

To search and develop the compounds exhibiting antifungal activities against the mycelial phase of Candida albicans, approximately 2,900 microorganisms isolated from soil were examined for antifungal activity. Among them, a strain with preferential activity against the mycelial phase of Candida albicans was isolated and identified as Streptomyces sp. A393. Isolation and purification of compounds A393 showing antifungal activity against the mycelial phase of C. albicans were performed using XAD-7 column chromatography, silica gel chromatography, preparative thin- layer silica gel chromatography, and HPLC. The molecular weights of compounds isolated from Streptomyces sp. A393 were determined as 774, 790, 804 and 820. These compounds appeared to have a structure of macrolide antibiotics, oligomycin A, B, C and E. Especially, oligomycin E, which is formerly reported to have no antifungal activity, showed antifungal activity against the mycelial phase of Candida albicans.