• Title/Summary/Keyword: anti-phase

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W-CDMA 30 Watts High Power Amplifier Using Anti-Phase Intermodulation Distortion Linearization Technology (Anti-Phase IMD 선형화 기술을 이용한 W-CDMA 30 W 대전력 증폭기)

  • Kang, Won-Tae;Do, Ji-Hoon;Chang, Jeong-Seok;Hong, Ui-Seok
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.18 no.7
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    • pp.723-730
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    • 2007
  • This paper shows how the ACLR of power amplifier can be reduced by using Anti-phase IMD linearization technique which generate anti-phase IMD in the driver stage compare to output stage's IMD. And design process proposed. From the experimental result of W-CDMA 4FA input signal, this amplifier has ACLR -55 dBc@5 MHz offset at 30 watts average power. Compare to optimum matching technique to get maximum power gain, this technique has been improved ACLR by 12 dBc. Also this amplifier meets 50 watts average output power amplifier specification in domestic market.

Effects of Te on the Anti-Galling Properties of Ni-Cr-Sn-Bi Alloy (Ni-Cr-Sn-Bi합금의 anti-galling 특성에 미치는 Te의 영향)

  • Ha Heon-Phil;Kim Kyung-Tak;Shim Jae Dong;Kim Yong Kyu
    • Korean Journal of Materials Research
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    • v.15 no.1
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    • pp.14-18
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    • 2005
  • Ni-Cr-Sn-Bi alloys were prepared by air melting and sand casting method and their anti-galling behaviors were examined. Anti-galling properties were dominantly influenced by Bi-rich low temperature precipitates. Alloying effects on the anti-galling properties were investigated for several alloying elements to improve anti-galling properties of the alloy. An alloy with $1-3wt\%$ of Te showed markedly improved anti-galling properties. Metallographic and tribological tests were carried out to find out reasons for excellent properties. It was found that Te containing alloy has finely distributed precipitates of Bi-rich phase. The addition of Te changed the morphology of the Ni-rich primary phase from globular to fine dendritic. As a result, the anti-galling phase precipitated between dendrite arms with fine distribution showed excellent anti-galling properties.

Anti-Counterfeiting Mechanism Based on RFID Tag Ownership Transfer Protocol (RFID 태그의 소유권 이전 프로토콜을 기반으로 한 위조 방지 메카니즘)

  • Lee, Jae-Dong
    • Journal of Korea Multimedia Society
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    • v.18 no.6
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    • pp.710-722
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    • 2015
  • Counterfeit products have been a major concern in global market. With the emergence of RFID systems, to detect counterfeit products in supply chain is relatively easy. Many anti-counterfeiting techniques for products attached by RFID tag are proposed. Most of the previous anti-counterfeiting techniques are not considering the distribution of the counterfeit from a customer to a customer. Using the ownership transfer protocols we can prevent the counterfeit from being distributed on the supply chain as well as between the customers and the customers. The ownership transfer protocols must be modified for anti-counterfeiting because of the usage of the protocol. In this paper, we modify the ownership transfer protocol proposed by G. Kapoor and S. Piramuthu[1] to be able to detect the counterfeit and track and trace the products in the supply chain. Our proposed protocol consists of three phases: the products delivery phase, the products takeover phase, and the products sale phase. We show that our protocol is anti-counterfeiting as well as secure against the security attacks.

Anti-nociceptive and Anti-inflammatory Effect of an Ethanol Extract of The Leaf and Stem of Aralia cordata

  • Jang, Ji Yeon;Seong, Yeon Hee
    • Natural Product Sciences
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    • v.20 no.4
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    • pp.301-305
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    • 2014
  • The aim of our study is to investigate the anti-nociceptive and anti-inflammatory properties of an ethanol extract of the leaf and stem of Aralia cordata. Writhing responses induced by acetic acid, tail immersion test, and formalin-induced paw pain response for nociception and formalin-induced paw edema for inflammation were evaluated in mice. A. cordata (50 - 200 mg/kg, p.o.) and ibuprofen (100 mg/kg, p.o.), a positive non-steroidal anti-inflammatory drugs (NSAIDs), inhibited the acetic acid-induced writhing response, but they did not protect the thermal nociception in tail immersion test. However, morphine (5 mg/kg, s.c.) used as positive opioid control alleviated both the acetic acid-induced writhing response and thermal nociception in tail immersion test. In the formalin test, A. cordata (50 - 200mg/kg) and ibuprofen (200mg/kg) inhibited the second phase response (peripheral inflammatory response), but not the first phase response (central response), whereas morphine inhibited both phase pain responses. Both A. cordata (100 mg/kg) and ibuprofen (200 mg/kg) significantly alleviated the formalin-induced increase of paw thickness, the index of inflammation. These results show for the first time that the leaf and stem of A. cordata has a significant anti-nociceptive effect that seems to be peripheral, but not central. A. cordata also displays an anti-inflammatory activity in an acute inflammation model. The present study supports a possible use of the leaf and stem of A. cordata to treat pain and inflammation.

Structural Studies of $A^{2+}$(Mg$_{1/3}$Nb$_{2/3}$)O$_3$,(A$^{2+}$=Sr$^{2+}$ and $Ca^{2+}$) Ceramics using High Resolution Transmission Electron Microscopy (고분해능 투과전자현미경을 이용한 $A^{2+}$(Mg$_{1/3}$Nb$_{2/3}$)O$_3$,(A$^{2+}$=Sr$^{2+}$ and $Ca^{2+}$) 세라믹스의 구조연구)

  • Ryu, Hyun;Nahm, Sahn;Byun, Jae-Dong;Lee, Hwack-Joo;Park, Hyun-Min
    • Journal of the Korean Ceramic Society
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    • v.36 no.7
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    • pp.762-766
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    • 1999
  • The crystal structure of A2+(Mg1/3Nb2/3)O3,(A2+=Sr2+ and Ca2+)ceramics was studied usig X-ray diffraction (XRD) and high resolution transmission electrion microscopy(HRTEM). Ba(Mg1/3Nb2/3)O3 (SMN) has the 1:2 ordered monoclinic structure which has the anti-phase tilt of octahedra. The type of tilting in SMN was considered to be a$^{\circ}$a$^{\circ}$c- or a­a­c$^{\circ}$ Ca(Mg1/3Nb2/3)O3 (CMN) also has the 1:2 ordered monoclinic structure which was distorted by the anti-phase tilt or in-phsae tilt of octahedra. A unit cell containing both the in-phase tilt axis and anti-phase tilt axis was not observed in the CMN. Therefore CMN has the mixed phase consisting of the 1:2 ordered monoclinic phase with anti-phase tilt of octahedra and the one with in -phase tilt of ocatahedra,. The anti-parallel shift of cation was also observed in the CMN.

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Anti-lipopolysaccharide antibody mitigates ruminal lipopolysaccharide release without acute-phase inflammation or liver transcriptomic responses in Holstein bulls

  • Mizuguchi, Hitoshi;Kizaki, Keiichiro;Kimura, Atsushi;Kushibiki, Shiro;Ikuta, Kentaro;Kim, Yo-Han;Sato, Shigeru
    • Journal of Veterinary Science
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    • v.22 no.3
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    • pp.34.1-34.7
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    • 2021
  • Anti-lipopolysaccharide (LPS) antibody administration has the potential benefits of neutralizing and consequently controlling rumen-derived LPS during subacute ruminal acidosis. Four Holstein bulls were used in this crossover study with a 2-week wash-out period. Anti-LPS antibody (0 or 4 g) was administered once daily for 14 days. Significantly lower ruminal LPS and higher 1-h mean ruminal pH were identified in the 4 g group. However, blood metabolites, acute-phase proteins, cytokines, and hepatic transcriptomes were not different between the two groups. Therefore, anti-LPS antibody administration mitigated ruminal LPS release and pH depression without accompanying responses in acute-phase inflammation or hepatic transcriptomic expression.

A Biotin-avidin Labeled Enzyme Immunoassay for the Quantitation of Serum TSH Using Protein-layered Solid Phase

  • Choi, Myung-Ja;Song, Eun-Young;Chung, Tai-Wha
    • Archives of Pharmacal Research
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    • v.21 no.3
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    • pp.231-235
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    • 1998
  • A sensitive enzyme immunoassay for serum TSH has been developed utilizing the tight binding between biotin and avidin, and three layered protein polystyrene beads as solid phase. To increase binding capacity of TSH and sensitivity of the assay, the polystyrene beads were coated sequentially with mouse immunoglobulin as first layer, rabbit antimouse immunoglobulin as second layer and monoclonal anti-TSH as third layer. A serum sample was incubated simultaneously with a monoclonal anti-TSH immobilized polystyrene beads and a second monoclonal anti-TSH covalently attached to biotin. After washing, the antibody bound serum TSH-anti-TSH-biotin complex is reacted with horseradish peroxidase (HRP)-labeled avidin. Following second wash, the bound HRP activity was measured calorimetrically. Reproducible results were obtained within 4 hours for serum TSH in the range between $0{\mu}\textrm{IU}$ml and ${50}{\mu}\textrm{IU}$ml with detection limit of $0.1{\mu}\textrm{IU}$ per test.

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Anti-Windup Scheme to Control DC Voltage of Three-Phase Four-Wire Active Power Filter (누적방지 기법을 적용한 3상 4선식 능동전력필터 시스템의 직류전압 제어)

  • 정교범
    • The Transactions of the Korean Institute of Power Electronics
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    • v.8 no.2
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    • pp.128-136
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    • 2003
  • This paper investigates the application of the anti-windup scheme to control U voltage of the three-phase four-wire active power filter, installed in a three-phase four-wire power system. In order to reduce efficiently the harmonic currents caused by the switching loads and to improve the whole performance of the flower system, the DC voltage of the three-phase four-wire active power filter should be properly controlled. PI controller can be applied to the U voltage controller of the three-phase four-wire active power filter. However, a large error input to PI controller leads to a windup phenomenon which deteriorate the dynamic characteristics of the U voltage controller Therefore, the application of the anti-windup scheme for the DC voltage controller is proposed and the improved performances of the anti-windup U voltage controller are proved through the computer simulation study.

Adaptive inverse feedback control of periodic noise for systems with nonminimum phase cancellation path (비최소위상 상쇄계를 가진 시스템을 위한 주기소음의 적응 역 궤환 제어)

  • Kim, Sun-Min;Park, Young-Jin
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.11a
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    • pp.437-442
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    • 2000
  • An alternative inverse feedback structure for adaptive active control of periodic noise is introduced for systems with nonminimum phase cancellation path. To obtain the inverse model of the nonminimum phase cancellation path, the cancellation path model can be factorized into a minimum phase term and a maximum phase term. The maximum phase term containing unstable zeros makes the inverse model unstable. To avoid the instability, we alter the inverse model of the maximum phase system into an anti-causal FIR one. An LMS predictor estimates the future samples of the noise, which are necessary for causality of both anti-causal FIR approximation for the stable inverse of the maximum phase system and time-delay existing in the cancellation path. The proposed method has a faster convergence behavior and a better transient response than the conventional FX-LMS algorithms with the same internal model control structure since a filtered reference signal is not required. We compare the proposed methods with the conventional methods through simulation studies.

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Analysis of Laser-protection Performance of Asymmetric-phase-mask Wavefront-coding Imaging Systems

  • Yangliang, Li;Qing, Ye;Lei, Wang;Hao, Zhang;Yunlong, Wu;Xian'an, Dou;Xiaoquan, Sun
    • Current Optics and Photonics
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    • v.7 no.1
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    • pp.1-14
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    • 2023
  • Wavefront-coding imaging can achieve high-quality imaging along with a wide range of defocus. In this paper, the anti-laser detection and damage performance of wavefront-coding imaging systems using different asymmetric phase masks are studied, through modeling and simulation. Based on FresnelKirchhoff diffraction theory, the laser-propagation model of the wavefront-coding imaging system is established. The model uses defocus distance rather than wave aberration to characterize the degree of defocus of an imaging system. Then, based on a given defocus range, an optimization method based on Fisher information is used to determine the optimal phase-mask parameters. Finally, the anti-laser detection and damage performance of asymmetric phase masks at different defocus distances and propagation distances are simulated and analyzed. When studying the influence of defocus distance, compared to conventional imaging, the maximum single-pixel receiving power and echo-detection receiving power of asymmetric phase masks are reduced by about one and two orders of magnitude respectively. When exploring the influence of propagation distance, the maximum single-pixel receiving power of asymmetric phase masks decreases by about one order of magnitude and remains stable, and the echodetection receiving power gradually decreases with increasing propagation distance, until it approaches zero.