• Title/Summary/Keyword: 2-Loop Structure

Search Result 455, Processing Time 0.035 seconds

Modal-based mixed vibration control for uncertain piezoelectric flexible structures

  • Xu, Yalan;Qian, Yu;Chen, Jianjun;Song, Gangbing
    • Structural Engineering and Mechanics
    • /
    • v.55 no.1
    • /
    • pp.229-244
    • /
    • 2015
  • H-infinity norm relates to the maximum in the frequency response function and H-infinity control method focuses on the case that the vibration is excited at the fundamental frequency, while 2-norm relates to the output energy of systems with the input of pulses or white noises and 2-norm control method weighs the overall vibration performance of systems. The trade-off between the performance in frequency-domain and that in time-domain may be achieved by integrating two indices in the mixed vibration control method. Based on the linear fractional state space representation in the modal space for a piezoelectric flexible structure with uncertain modal parameters and un-modeled residual high-frequency modes, a mixed dynamic output feedback control design method is proposed to suppress the structural vibration. Using the linear matrix inequality (LMI) technique, the initial populations are generated by the designing of robust control laws with different H-infinity performance indices before the robust 2-norm performance index of the closed-loop system is included in the fitness function of optimization. A flexible beam structure with a piezoelectric sensor and a piezoelectric actuator are used as the subject for numerical studies. Compared with the velocity feedback control method, the numerical simulation results show the effectiveness of the proposed method.

The Actin-Related Protein BAF53 Is Essential for Chromosomal Subdomain Integrity

  • Lee, Kiwon;Kim, Ji Hye;Kwon, Hyockman
    • Molecules and Cells
    • /
    • v.38 no.9
    • /
    • pp.789-795
    • /
    • 2015
  • A chromosome territory is composed of chromosomal subdomains. The internal structure of chromosomal subdomains provides a structural framework for many genomic activities such as replication and DNA repair, and thus is key to determining the basis of their mechanisms. However, the internal structure and regulating proteins of a chromosomal subdomain remains elusive. Previously, we showed that the chromosome territory expanded after BAF53 knockdown. Because the integrity of chromosomal subdomains is a deciding factor of the volume of a chromosome territory, we examined here the effect of BAF53 knockdown on chromosomal subdomains. We found that BAF53 knockdown led to the disintegration of histone H2B-GFP-visualized chromosomal subdomains and BrdU-labeled replication foci. In addition, the size of DNA loops measured by the maximum fluorescent halo technique increased and became irregular after BAF53 knockdown, indicating DNA loops were released from the residual nuclear structure. These data can be accounted for by the model that BAF53 is prerequisite for maintaining the structural integrity of chromosomal subdomains.

Structure-antibiotic Acitivity Relationships of Brevinin-1 and Thanatin Containing Rana Box (Rana box를 포함한 Brevinin-1 및 Thanatin의 구조-상생활성 상관관계)

  • 신송엽;강주현;이동건;장소윤;서무열;함경수
    • Microbiology and Biotechnology Letters
    • /
    • v.27 no.6
    • /
    • pp.440-445
    • /
    • 1999
  • In order to investigate structure-antibiotic activity relationships of brevinin-1 and thanatin containing Rana box composed of basic loop formed by disulfide bridge in their arboxy terminus, thanatin, brevinin 1 and their analogues (T-B1, T-B2 and B-T) in which their Rana box sequence exchanged was designed and synthesized by the solid phase method using Fmoc-chemistry. The basic sequence of Rana box of thanatin had more significant effect on both antibacterial and antifungal activity than that of brevinin 1. The tail sequence (QRM) of thanatin was found to be important in its antibacterial and antifungal activity. Rana box sequence of brevinin-1 did not have a significant effect on its antitumor and phospholipid vesicle-aggregating activities. Brevinin-1 showed stronger $\alpha$-helical structure in the membrane-mimicking environment such as SDS micelle than thanatin. A remarkable increase in a-helicity of bervinin-1 plays more important role in antibiotic activity than that of thanatin. Furthermore, antibacterial activity of thanatin against E. coli resulted from the disruptive effect against the outer cell membrane of E. coli.

  • PDF

Fabrication and Characterization of the BLT/STA/Si Structure for Fe-FETs Application

  • Park, Kwang-Huna;Jeon, Ho-Seung;Park, Jun-Seo;Im, Jong-Hyun;Park, Byung-Eun;Kim, Chul-Ju
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2006.11a
    • /
    • pp.73-74
    • /
    • 2006
  • Ferroelectric thin films have been widely investigated for future nonvolatile memory application. We fabricated the BLT ($(Bi,La)_4Ti_3O_{12}$) films on Si using a STA ($SrTa_2O_6$) buffer layer BLT and STA film were prepared by sol-gel method. Measurement data by XRD and AFM, showed that BLT film and STA films were well crystallized and a good surface morphology. From C-V measurement reward that the Au/BLT/STA/Si structure showed a clockwise hysteresis loop with a memory window of 1.5 V for the bias voltage sweep of ${\pm}5$ V. From results, the Au/BLT/STA/Si structure is useful for FeFETs.

  • PDF

Design of the Compact Microstrip Bandpass Filter by using DGS Resonator (DGS 공진기를 이용한 소형 마이크로스트립 대역통과 필터의 설계)

  • Cho, Young-Bin;Jun, Kye-Suk
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.30 no.2A
    • /
    • pp.147-152
    • /
    • 2005
  • In this paper, we have proposed a novel DGS(Defected Ground Structure) resonator and has designed the band -pass filter using the proposed ${\subset}$ stub-I type DGS resonator. This structure has strong advantages that can vary the retune loss at the passband freely and also can easily tune the attenuation pole frequency at the stopband. The bandpass filter can be made more smaller than the existing filters and be used to find the various applications for eliminating the harmonics and spurious mode at IMT-2000 band.

A Comparative Genome-Wide Analysis of GATA Transcription Factors in Fungi

  • Park, Jong-Sun;Kim, Hyo-Jeong;Kim, Soon-Ok;Kong, Sung-Hyung;Park, Jae-Jin;Kim, Se-Ryun;Han, Hyea-Young;Park, Bong-Soo;Jung, Kyong-Yong;Lee, Yong-Hwan
    • Genomics & Informatics
    • /
    • v.4 no.4
    • /
    • pp.147-160
    • /
    • 2006
  • GATA transcription factors are widespread eukaryotic regulators whose DNA-binding domain is a class IV zinc finger motif in the form $CX_{2}CX_{17-20}CX_{2}C$followed by a basic region. In fungi, they act as transcriptional activators or repressors in several different processes, ranging from nitrogen source utilization to mating-type switching. Using an in-house bioinformatics portal system, we surveyed 50 fungal and 9 out-group genomes and identified 396 putative fungal GATA transcription factors. The proportion of GATA transcription factors within a genome varied among taxonomic lineages. Subsequent analyses of phylogenetic relationships among the fungal GATA transcription factors, as well as a study of their domain architecture and gene structure, demonstrated high degrees of conservation in type IVa and type IVb zinc finger motifs and the existence of distinctive clusters at least at the level of subphylum. The SFH1 subgroup with a 20-residue loop was newly identified, in addition to six well-defined subgroups in the subphylum Pezizomycotina. Furthermore, a novel GATA motif with a 2f-residue loop ($CX_{2}CX_{21}CX_{2}C$, designated 'zinc finger type IVc') was discovered within the phylum Basidiomycota. Our results suggest that fungal GATA factors might have undergone multiple distinct modes of evolution resulting in diversified cellular modulation in fungi.

Design of Low Voltage 1.8V, Wide Range 50∼500MHz Delay Locked Loop for DDR SDRAM (DDR SDRAM을 위한 저전압 1.8V 광대역 50∼500MHz Delay Locked Loop의 설계)

  • Koo, In-Jae;Chung, Kang-Min
    • The KIPS Transactions:PartA
    • /
    • v.10A no.3
    • /
    • pp.247-254
    • /
    • 2003
  • This paper describes a Delay Locked Loop (DLL) with low supply voltage and wide lock range for Synchronous DRAM which employs Double Data Rate (DDR) technique for faster data transmission. To obtain high resolution and fast lock-on time, a new type of phase detector is designed. The new counter and lock indicator structure are suggested based on the Dual-clock dual-data Flip Flop (DCDD FF). The DCDD FF reduces the size of counter and lock indicator by about 70%. The delay line is composed of coarse and fine units. By the use of fast phase detector, the coarse delay line can detect minute phase difference of 0.2 nsec and below. Aided further by the new type of 3-step vernier fine delay line, this DLL circuit achieves unprecedented timing resolution of 25psec. This DLL spans wide locking range from 500MHz to 500MHz and generates high-speed clocks with fast lock-on time of less than 5 clocks. When designed using 0.25 um CMOS technology with 1.8V supply voltage, the circuit consumes 32mA at 500MHz locked condition. This circuit can be also used for other applications as well, such as synchronization of high frequency communication systems.

A Convenient Radiolabeling of [$^{11}$C](R)-PK11195 Using Loop Method in Automatic Synthesis Module ($^{11}$C 표지 자동합성장치에서 루프법을 이용한 ($^{11}$C)(R)-PK11195의 간편한 합성법)

  • Lee, Hak-Jeong;Jeong, Jae-Min;Lee, Yun-Sang;Kim, Hyung-Woo;Choi, Jae-Yeon;Lee, Dong-Soo;Chung, June-Key;Lee, Myung-Chul
    • Nuclear Medicine and Molecular Imaging
    • /
    • v.43 no.4
    • /
    • pp.337-343
    • /
    • 2009
  • Purpose: ((R)-1-(2-chlorophenyl)-N-1-[$^{11}$C]methyl-N(1-propyl)-3-isoquinoline carboxamide ((R)-PK11195) is a specific ligand for the peripheral type benzodiazepine receptor and a marker of activated microglia, used to measure inflammation in neurologic disorders. We report here that a direct and simple radiosynthesis of [$^{11}$C](R)-PK11195 in mild condition using NaH suspension in DMF and one-step loop method. Materials and Methods: (R)-N-Desmethyl-PK11195 (1 mg) in DMSO (0.1 mL) and NaH suspension in DMF (0.1 mL) were injected into a semi-prep HPLC loop. [$^{11}$C]methyl iodide was passed through HPLC loop at room temperature. Purification was performed using semi-preparative HPLC. Aliquots eluted at 11.3 min were collected and analyzed by analytical HPLC and mass spectrometer. Results: The labeling efficiency of [$^{11}$C](R)-PK11195 was 71.8$\pm$8.5%. The specific activity was 11.8:$\pm$6.4 GBq/$\mu$mol and radiochemical purity was higher than 99.2%. The mass spectrum of the product eluted at 11.3 min showed m/z peaks at 353.1 (M+1), indicating the mass and structure of (R)-PK11195. Conclusion: By the one-step loop method with the [$^{11}$C]CH3l automated synthesis module, [$^{11}C$](R)-PK11195 could be easily prepared in high radiochemical yield using NaH suspension in DMF.

A photoelastic study on the initial stress distribution of the upper anterior teeth retraction using combination loop archwire and sliding mechanics (Combination loon archwire와 활주역학을 이용한 상악전치의 후방 견인시 나타나는 초기 응력 분포에 관한 광탄성학적 연구)

  • Yim, Kang-Soon;Lee, Jin-Woo;Cha, Kyung-Suk
    • The korean journal of orthodontics
    • /
    • v.34 no.4 s.105
    • /
    • pp.303-312
    • /
    • 2004
  • An unfavorable tipping movement can occur during the retraction of anterior teeth because orthodontic force is loaded by brackets positioned far from the center of resistance. To avoid this unfavorable movement, a compensating curved wire or lingual root torque wire is used. The purpose of this study is to investigate, using photoelastic material, the distribution of initial stress associated with the retraction of the incisors according to the degree of the compensating curve, to model changes associated with tooth ud alveolar bone structure. The following results were obtained by analysis of the polarizing plate of the effects of initial stress resulting from retraction of the anterior teeth: 1. When the incisors were retracted using combination archwire or sliding mechanics, the maximal polarizing pattern of the apical area decreased as the degree of the compensating owe increased from 0 to 15 to 30. 2. When the incisors were retracted by the combination archwire or sliding mechanics, the maximal polarizing pattern of the canine and premolar area increased as the degree of the compensating curve increased from 0to 15to 30. 3. A lower degree of polarizing patterns were associated with the combination archwire technique than the sliding mechanics technique at a given force. The above results indicate that there is no significant difference between the combination loop archwire technique and sliding mechanics, for the retraction of maxillary anterior teeth with decreased lingual tipping tendency by a compensating curve on the arch wire. However, the use of sliding mechanics is more effective for the prevention of lingual inclination of the anterior teeth, because the hook used in sliding mechanics is closer to the center of resistance of the maxillary anterior teeth.

Analysis of Antenna Isolation Using Decoupling Structure (격리구조 기법을 이용한 안테나 격리도 변화 분석)

  • Lee, Junghun;Kim, Jihoon;Kim, Min-Gi;Kim, Hyung-Hoon;Kim, Hyeong-Dong
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.26 no.12
    • /
    • pp.1044-1049
    • /
    • 2015
  • In this paper, isolation enhanced antenna using isolating resonator was proposed. Two loop type antennas were designed to operate at Wi-Fi band(2.4~2.5 GHz), in symmetry to the center, and are closely located to each other. In order to enhance isolation characteristics at Wi-Fi bands, isolating resonator was designed between the two loop type antennas. The proposed isolating resonator is a slot type antenna that enhances isolation with the control of the size, and by adjusting the value of capacitor($C_D$) the resonant frequency of the isolating resonator can easily be adjusted to enhance isolation characteristic at the target frequency.