• Proceedings of the KIEE Conference
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• 1987.07a
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• pp.786-790
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• 1987

An optimization problem minimizing n given time-weighted performance index for discrete-time linear multi-input systems is investigated for the prespecified closed-loop eigenvalues. Necessary conditions for an optimality of the controller that satisfies the specified closed-loop eigenvalues are derived. A computational algorithm solving the optimal constant feedback gain is presented and a numerical example is given to show the effect of a time-weighted performance index on the transient responses.

• Journal of the Korea Institute of Military Science and Technology
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• v.9 no.1 s.24
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• pp.144-151
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• 2006

A rectangular loop antenna for S-band radar is proposed. The proposed loop antenna is the modified type of folded monopole antenna. The feeding line is coplanar stripline with $180^{\circ}$ phase difference for operating in odd mode. The proposed antenna showed return loss of -15.57dB at the center frequency and bandwidth of about 790MHz (> 25%) under the condition of VSWR < 2. The gains of single, 1x2, and 1x4 array loop antennas are 4.3, 7.0, and 10.2dBi, respectively.

• Korean Journal of Microbiology
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• v.42 no.2
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• pp.156-159
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• 2006

A base substitution was introduced at the position 789 in Escherichia coli 16S rRNA, which was previously identified as an invariant residue for ribosome function and the ability of the mutant ribosomes to translate chloramphenicol acetyltransfernse mRNA was measured by determining the degree of resistance to chloramphenicol of cells expressing these mutant ribosomes. As expected, mutant ribosomes containing a base sub-stitution at the position 789 showed significantly reduced protein-synthesis ability and to identify a functional role played by this residue in protein synthesis, we developed an efficient genetic method to select second-site revertants in 16S rRNA that restore protein-synthesis function to these mutant ribosomes.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10b
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• pp.963-968
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• 1990

An iterative learning control scheme for tracking control of a class of uncertain nonlinear systems is presented. By introducing a model reference adaptive controller in the learning control structure, it is possible to achieve zero tracking of unknown system even when the upperbound of uncertainty in system dynamics is not known apriori. The adaptive controller pull the state of the system to the state of reference model via control gain adaptation at each iteration, while the learning controller attracts the model state to the desired one by synthesizing a suitable control input along with iteration numbers. In the controller role transition from the adaptive to the learning controller takes place in gradually as learning proceeds. Another feature of this control scheme is that robustness to bounded input disturbances is guaranteed by the linear controller in the feedback loop of the learning control scheme. In addition, since the proposed controller does not require any knowledge of the dynamic parameters of the system, it is flexible under uncertain environments. With these facts, computational easiness makes the learning scheme more feasible. Computer simulation results for the dynamic control of a two-axis robot manipulator shows a good performance of the scheme in relatively high speed operation of trajectory tracking.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04a
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• pp.788-790
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• 2003

본 논문은 멀티미디어를 위한 초고속 통신망으로서의 역할을 하고 있는 VDSL망에서, 라디오 주파수 인터피어런스(RFI: Radio Frequency Interference)가 가해진 VDSL 시스템의 데이터 전송 능력을 분석하였다. 이를 위해 ANSI 표준문서와 FSAN의 제안서를 참조하여 VDSL관점에서 ANSI DSL Standard Group T1E1.4에 제시된 VDSL Test Loop를 사용하였다. .국내에서 사용되고 있는 아마추어 무선(HAM)용 주파수 대역에 적용한 경우에 대해 VDSL 전송 능력을 파악하였으며, 이를 위해 Matlab tool을 이용하여 컴퓨터 시뮬레이션 하였다. VDSL 방식 이론에 근거한 전승 속도에 대한 계산에서, RFI 유입을 방지하기 위해 notch를 형성한 PSD(Power Spectral Density)를 사용하였으며, 이에 대한 실험을 통하여 VDSL 시스템의 전송 속도 감소를 확인하였다.

• Archives of Pharmacal Research
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• v.29 no.1
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• pp.88-95
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• 2006

Analysis of molecular nature of mitochondrial DNA (mtDNA) could be powerful marker for anthropological studies of modern populations. While population genetic studies on mtDNA have been reported for several ethnic groups, no such study has been documented for the Korean population. We surveyed mtDNA polymorphisms in the HVS I of noncoding D-loop region and its upstream region from 430 unrelated healthy Korean population by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and direct sequencing analysis. PCR product with 2,790 bp spanning the specific mtDNA region (mt13715-16504) was subjected to RFLP analysis using 6 restriction enzyme (Hinf I, Hae III, Alu I, Dde I, Mbo I, Rsa I). On the PAUP analysis of PCR-RFLP results, 38 mtDNA haplotypes (Hap 1-38) were detected in the Korean populations, which were classified into 11 haplogroups (Grp 1-11) of related haplotypes encompassing all 38 haplotypes. In comparison of sequencing data with Anderson's reference sequence, the transition type was more prevalent than the transversion type. Insertions or deletions were not found. In addition, three of the polymorphic sites (A16240C, A16351G, G16384A) in HVS-I region are determined newly. The polymorphic sites were distributed randomly in the region, though the frequency at each site was variable. Thus, this research might be required for the genealogical study of Orientals.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.8 s.99
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• pp.790-796
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• 2005

In order to accomplish a wireless communication of capsule endoscopy, an environment study in the human body and receiving antenna design have been performed. The proposed antenna is the loop antenna designed to minimize the propagation loss in multi-loss layer such as the human body and utilize the magnetic field. Considering the propagation loss in the human body, the frequency range is from 400 MHz to 500 MHz. Acorrrding to the FCC regulations, the permittivity and conductivity for each human tissue were extracted. We set up an equivalent model and make an aqueous solution which is replaced with the human body. Due to movement of capsule in the human body which propagation loss is extremly severe, an array antenna is required. Irrespective of the location of transmission antenna transmitting a signal of 1 mW, we confirme what it is possible for the enough signal detection as the average signal level of array antenna is -60 dBm.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.8C
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• pp.790-800
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• 2009

For the improvement of coding efficiency, the H.264/AYC standard uses new coding tools such as 1/4-pel-accurate motion estimation, multiple references, intra prediction, loop filter, variable block size etc. Using these coding tools, H.264/AYC has achieved significant improvements from rate-distortion point of view compared to existing standards. However, the encoder complexity was greatly increased due to these coding tools. We focus on the complexity reduction method of intra macroblock mode selection. The proposed algorithm for fast intra mode selection calculates the edge activity in transform domain, and performs fast encoding of intra frame in H.264/AYC through the fast prediction mode selection of intra4x4 and chrominance blocks. Simulation results show that the proposed method saves about 59.76% for QCIF sequences and 65.03% for CIF sequences of total encoding time, while bitrate increase and PSNR decrease are very small.