• Proceedings of the KIEE Conference
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• 1990.11a
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• pp.391-395
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• 1990

A new control algorithm is developed to achieve the robust performance of the system during the overall control process. Time-varying sliding manifolds are proposed to remove the reaching phase which is one of common shortcomings of variable structure control scheme. A necessary and sufficient condition for the existence of a sliding mode on the newly proposed time-varying sliding mode on the newly proposed time-varying sliding manifolds is derived by Lyapunov's second method. The digital simulation results show that the newly proposed control algorithm is superior to the typical variable structure control algorithm with respect to the robust performance of the system. The simplicity of the proposed control algorithm encourages control engineers to implement the proposed control algorithm in many control problems.

• Journal of the Korean housing association
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• v.13 no.5
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• pp.71-76
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• 2002

Recently, much attention has been paid to the problem such as sick building syndrome, which caused by the air pollutant indoor. In addition, Volatile Organic Compounds(VOCs) has been paid attention to as one of the main reason that causes air pollutant indoor, and the exposure of VOCs indoor is recognizes as an important factor which have an effect on the health of resident. In this study, measuring of VOCs in newly houses, and the results are as follows; 1)TVOC(Total Volatile Organic Compounds) indoor is detected high concentration(11314$\mu\textrm{g}$/㎤). 2)There are detected acetaldehyde, methylenechloride, benzene, trichloroethylene and styrene that have to take precaution against human carcinogenicity

• Journal of Ecology and Environment
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• v.36 no.4
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• pp.315-325
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• 2013

Taxa in the order Chlorococcales inhabiting Hongcheon River, South Korea were collected and identified from December 2011 to September 2012. As a result, nine taxa in the Order Chlorococcales including unrecorded genera Oocystidium and Heleococcus were newly added to the Korean flora: Oocystidium ovale, Heleococcus mucicola, Chlorella mirabilis, Monoraphidium convolutum var. pseudosabulosum, M. minutum, Raphidocelis mucosa, Eutetramorus tetrasporus, Scenedesmus flavescens, and S. multicauda. The morphological characteristics of the nine taxa identified in this study mostly corresponded to already reported characteristics; however, M. minutum had a shorter cell length than the recorded description, Raphidocelis mucosa and S. flavescens were larger than previous descriptions, and Scenedesmus multicauda had larger spines than the cell itself. Eight of the nine taxa were found in planktonic samples, whereas Heleococcus mucicola was found in an epilithic sample. Therefore the Korean order Chlorococcales, including these newly reported ones, totals to 255 species.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.5
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• pp.75-85
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• 1998

This paper presents the procedures and technique of the decision on the decision on the mount in a diesel engine development newly. To assess the vibration chara- cteristics of the engine plus transmission, their inertia moments are calculated for three engine versions. i.e., NA(Naturally Aspirated), TC(Turbocharged) and TCI(Turbocharged and Intercooled). These data are used to determine the mount layout and stiffness values affecting the noise quality of an engine as well as a vehicle. The main purpose of this paper is to design the mount rubber having the optimal stiffness characteristics through the investigation of the calculation results and the mount conditions when an engine is installed in a vehicle using the existing engine mount room. Thus, this paper describes the optimal mount positions, rubber stiffnesses, natural frequency, mode shapes and so on using ADAMS program to apply the newly developed engines to three different vehicles.

• Journal of KSNVE
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• v.11 no.1
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• pp.49-56
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• 2001

In this paper, two plant models, of which one is newly developed and the other one is the conventional one, of the focus servo system of DVD drive are presented and a two-degree-of freedom controller consisted of Inverse dynamics feedforward and LQG/LTR feedback controller is designed. The newly developed plant model is used to design the feedforward controller and the conventional model is used for the design of feedback controller. The output of newly developed model is the displacement of objective lens and the output of conventional model is the focus error of the DVD focus servo system. The displacement of the objective lens is estimated by the dynamics model of the DVD focus servo system. The disturbance rejection performance of the two-degree-of freedom controller is compared with that of an LQG/LTR one.

• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.462-465
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• 1991

In this paper, a newly developed uninterruptible power supply adopted insulated gate bipolar transistors (IGBT'S) is introduced. The focus is on harmonic reduction, high efficiency and so on. The overview, hardware and software of the newly developed ups system are also discussed. Finally, the merit of the newly developed ups compared with conventional ups is described.

• Korean Journal of Microbiology
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• v.12 no.1
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• pp.37-51
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• 1974

Three strains which accumulated large quantities of L-hlutamic acid as the chief product of metabolism in the presence of glucose and inorhanic ammonium salt under the aerobic condition sere newly isolated. These strains have the general characters as follows: Gram-positive, short fod-shaped, non-sporulating, non-motile, and facultative anaerobe. A change of cell shates was not almost observed in their life cycles and neither a phenomenon of cell-elongation nor a pleomorphism was recognized in any cases. Together with rigid stability in Gram-stain, these characters as above indicated evidences that newly isolates would belong to genus Brevibacterium clearly differentiated from genus Corynebacterium. At the same time the newly isolates, in addition to nutritional requirement of biotin and thiamine, showed the distinctive character of requirement of special amino acid such as histidine or cysteine for their considerable growth. These physiological characters including nitrates reduction, reaction on milk, and slow formation of acid from sugar also were useful in confirming that these bacteria would be Brevibacterium ammoniagenes.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.11
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• pp.2127-2130
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• 2008

In this paper, a tunable bandpass filter with mutual inductive coupling circuits is newly designed and demonstrated for UHF TV tuner ranged from Ch.14(473MHz) to Ch.69(803MHz) applications. Conventional HF tuning circuit with an electromagnetic bandpass filter has several problems such as large size, high volume and high cost, since the electromagnetic filter is comprised of several passive components and air core inductors to be assembled and controlled manually. To address these obstacles, peaking chip inductor was newly applied for constructing the mutual inductive coupling circuit. The proposed circuit was newly and optimally designed, since the chip inductor showed lower components Q-value than the air core inductor. A varactor diode has been also used to fabricate the proposed tunable bandpass filter for RF tuning circuit. The fabricated tunable filter exhibited low insertion loss of approximately -3dB, high return loss of below -10dB, and large tuning bandwidth of 330MHz.

• Journal of Korean Institute of Industrial Engineers
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• v.34 no.1
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• pp.32-41
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• 2008

This paper studies a joint EOQ and EPQ model in which a stationary demand can be satisfied by recycled products as well as newly purchased products. The model assumes that a fixed quantity of the used products are collected from customers and later recovered for reuse. The recovered products are regarded as perfectly new ones. We also assume that the number of orders for newly purchasing items and the number of recovery setups in a cycle can be mutually independent integers. Under these assumptions, we develop an optimization model obtaining the economic order quantity for newly procured products, the optimal lot size for the recovery process, and the sequence of the orders and the setups, simultaneously. And then a simple solution procedure to find a local optimal control parameter set is proposed. To validate the model and the solution procedure, finally, some computational experiments are presented.

• Animal Systematics, Evolution and Diversity
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• v.33 no.4
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• pp.278-283
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• 2017

One of the largest genera of subfamily Ophioninae, Ophion, has been reported 144 species in the World. Nevertheless, recorded members of genus Ophion are 40 species in the Eastern Palaearctic region, 8 in South Korea (O. ainoicus, O. choaspese, O. flavopictus, O. fuscomaculatus, O. luteus luteus, O. obscuratus obscuratus, O. okunii, O. takaozanus). In this paper, a taxonomic list of genus Ophion from South Korea is provided for the first time. Two newly recorded species, Ophion hokkaidonis Uchida and Ophion nikkonis Uchida, are reported from South Korea. A key to these South Korean species, diagnoses of the two newly recorded species and digital images are provided.