• Title/Summary/Keyword: Anti-Form

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EA-based Tuning of a PID Controller with an Anti-windup Scheme (안티와인드업 기법을 가지는 PID 제어기의 EA 기반 동조)

  • Jin, Gang-Gyoo;Park, Dong-Jin
    • Journal of Institute of Control, Robotics and Systems
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    • v.19 no.10
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    • pp.867-872
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    • 2013
  • Many practical processes in industry have nonlinearities of some forms. One commonly encountered form is actuator saturation which can cause a detrimental effect known as integrator windup. Therefore, a strategy of attenuating the effects of integrator windup is required to guarantee the stability and performance of the overall control system. In this paper, optimal tuning of a PID (Proportional-Integral-Derivative) controller with an anti-windup scheme is presented to enhance the tracking performance of the PID control system in the presence of the actuator saturation. First, we investigate effective anti-windup schemes. Then, the parameters of both the PID controller and the anti-windup scheme are optimally tuned by an EA (Evolutionary Algorithm) such as the IAE (Integral of Absolute Error) is minimized. A set of simulation works on two high-order processes demonstrates the benefit of the proposed method.

Anti-Windup Strategy of PI Controller without Overshoot (오버슈터 없는 PI 제어기의 Anti-Windup 기법)

  • Yun, Won-Eel;Choi, Jong-Woo;Kim, Heung-Geun
    • Proceedings of the KIPE Conference
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    • 2005.07a
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    • pp.538-541
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    • 2005
  • Most realistic control systems contain nonlinearities of some form. One nonlinearity commonly found in control systems is a saturating element. If integral control is applied to such a system to eliminate steady state error, an undesired side effect known as integrator windup may occur when lage setpoint changes are made. This effect leads to a characteristic step response with a large overshoot and a very high settling time. To avoid this situation, many different anti-windup strategies have been suggested. But existing strategies remain over shoot and high settling time. This paper proposes a new anti-windup strategy for PI speed controllers. When the speed control system is changed P controller to PI controller. Integrator has an appropriate initial value. This value results over shoot and high settling time. The SIMULINK/MATLAB-based comparative simulation results and experiment results of speed controller have shown its superior control performance to that of a proposed anti-windup speed controller.

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Role of N-terminal Hydrophilic Amino Acids in Molecular Translocation of CTLA-4 to Cell Surface (CTLA-4 항원의 세포막 도달 기작에서 친수성 N말단 아미노산 잔기의 역할)

  • Han, Ji-Woong;Lee, Hye-Ja;Kim, Jin-Mi;Choi, Eun-Young;Chung, Hyun-Joo;Lim, Soo-Bin;Choi, Jang-Won;Chung, Yong-Hoon
    • IMMUNE NETWORK
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    • v.2 no.2
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    • pp.102-108
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    • 2002
  • Background: This study was aimed to differentiate two forms of CTLA-4 (CD152) in activated peripheral blood lymphocyte and clarify the mechanism how cytoplasmic form of this molecule is targeted to cell surface. Methods: For this purpose we generated 2 different anti-human CD152 peptide antibodies and 5 different N'-terminal deletion mutant CTLA4Ig fusion proteins and carried out a series of Western blot and ELISA analyses. Antipeptide antibodies made in this study were anti-CTLA4pB and anti-CTLA4pN. The former recognized a region on extracellular single V-like domain and the latter recognized N'-terminal sequence of leader domain of human CD152. Results: In Western blot, the former antibody recognized recombinant human CTLA4Ig fusion protein as an antigen. And this recognition was completely blocked by preincubating antipeptide antibody with the peptide used for the antibody generation at the peptide concentration of 200 ug/ml. These antibodies were recognized human CD152 as a cytoplasmic sequestered- and a membrane bound- forms in phytohemagglutinin (PHA)-stimulated peripheral blood lymphocyte (PBL). These two forms of CD152 were further differentiated by using anti-CTLA4pN and anti-CTLA4pB antibodies such that former recognized cytosolic form only while latter recognized both cytoplasmic- and membraneforms of this molecule. Furthermore, in a transfection expression study of 5 different N'-terminal deletion mutant CTLA4Ig, mutated proteins were secreted out from transfected cell surface only when more than 6 amino acids from N'-terminal were deleted. Conclusion: Our results implies that cytosolic form of CTLA-4 has leader sequence while membrane form of this molecule does not. And also suggested is that at least N'-terminal 6 amino acid residues of human CTLA-4 are required for regulation of targeting this molecule from cytosolic- to membrane- area of activated human peripheral blood T lymphocyte.

Interleukin-9 Inhibits Lung Metastasis of Melanoma through Stimulating Anti-Tumor M1 Macrophages

  • Park, Sang Min;Do-Thi, Van Anh;Lee, Jie-Oh;Lee, Hayyoung;Kim, Young Sang
    • Molecules and Cells
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    • v.43 no.5
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    • pp.479-490
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    • 2020
  • Interleukin-9 (IL-9) is well known for its role in allergic inflammation. For cancer, both pro- and anti-tumor effects of IL-9 were controversially reported, but the impact of IL-9 on tumor metastasis has not yet been clarified. In this study, IL-9 was expressed as a secretory form (sIL-9) and a membrane-bound form (mbIL-9) on B16F10 melanoma cells. The mbIL-9 was engineered as a chimeric protein with the transmembrane and cytoplasmic region of TNF-α. The effect of either mbIL-9 or sIL-9 expressing cells were analyzed on the metastasis capability of the cancer cells. After three weeks of tumor implantation into C57BL/6 mice through the tail vein, the number of tumor modules in lungs injected with IL-9 expressing B16F10 was 5-fold less than that of control groups. The percentages of CD4+ T cells, CD8+ T cells, NK cells, and M1 macrophages considerably increased in the lungs of the mice injected with IL-9 expressing cells. Among them, the M1 macrophage subset was the most significantly enhanced. Furthermore, peritoneal macrophages, which were stimulated with either sIL-9 or mbIL-9 expressing transfectant, exerted higher anti-tumor cytotoxicity compared with that of the mock control. The IL-9-stimulated peritoneal macrophages were highly polarized to M1 phenotype. Stimulation of RAW264.7 macrophages with sIL-9 or mbIL-9 expressing cells also significantly increased the cytotoxicity of those macrophages against wild-type B16F10 cells. These results clearly demonstrate that IL-9 can induce an anti-metastasis effect by enhancing the polarization and proliferation of M1 macrophages.

Skin Permeation and Anti-inflammatory Effects of Hydrolyzed Products of Gardeniae Fructus Extracts (치자 엑스의 가수분해에 의한 피부투과 및 항염효과)

  • Yang, Jae-Heon;Lee, Nam-Hee
    • Journal of Pharmaceutical Investigation
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    • v.34 no.2
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    • pp.115-123
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    • 2004
  • Geniposide and its related iridoid compounds have been used in traditional herbal medicine for thε treatment of Jaundice hepatic diseases and various inflammatorys. For the purpose to increase trandsdermal absorption, the hydrolyzed products of Gardeniae Furctus were identified and assayed of active ingredients and investigated trandsdermal absorption and anti-inflammatory effects. Geniposide was hydrolyzed to genipin by ${\beta}-glucosidase$ and it was suggested that genipin was more suitable form than geniposide for transdermal absorption by its lipophilic property. Using Franz type diffusion cell and the skin of hairless mouse, the permeation rate of hydrolyzed products and their emulsion preparation were determined. Genipin have more increased absorption ratio through the skin of hairless mouse than geniposide. Also, the emulsion of hydrolyzed products of extracts showed higher permeability than that of nonhydrolyzed preparations. After 9 hours $280.85\;{\mu}g/cm^2$ of genipin was absorbed and $193.52\;{\mu}g/cm^2$ in case of geniposide. The Js of geniposide and genipin were $26.27{\pm}4.11\;{\mu}g/cm^2/hr$ and $40.35{\pm}5.04\;{\mu}g/cm^2/hr$ respectively. After carrageenan injection, the swelling was increased repidly to 24 hr and maintained as plateau. but emulsion group weer reached about 2.5 mL and the swelling decreased successively form 24 hr to 72 hr. The anti-inflammation effects of extracts and hydrolyzed products emulsion were increased with significant difference with control group after 24 hr, 48 hr and 72 hr. In carrageenan induced edema, inhibition of swelling was increased in case of hydrolyzed product emulsion compare with nonhydrolyzed group at 24 hr, 48 hr and 72 hr after swelling. In histological study, the anti-inflammatory effects of hydrolyzed products were remarkable at 48 hr and 72 hr compare with nonhydrolyzed. Hydrolyzed products of Gardeniae Fructus extracts containing genipin would be a suitable preparation to increase the transdermal absorption and anti-inflammatory effects.

Induction of anti-aquaporin 5 autoantibodies by molecular mimicry in mice

  • Lee, Ahreum;Choi, Youngnim
    • International Journal of Oral Biology
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    • v.45 no.4
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    • pp.211-217
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    • 2020
  • Molecular mimicry is the most common mechanism that breaches self-tolerance. We previously identified autoantibodies to aquaporin-5 (AQP5) in the sera of patients with Sjögren's syndrome and found that the aquaporin of Prevotella melaninogenica (PmAqp), an oral commensal, is highly homologous to human AQP5. This study aimed to test whether PmAqp can induce anti-AQP5 autoantibodies via molecular mimicry. From the amino acid sequence of PmAqp, an immunizing peptide; i.e., PmE-L, was designed, which contained both the B cell epitope "E" and T cell epitope. C57BL/6 and BALB/c mice were subcutaneously immunized with linear or cyclic forms of PmE-L emulsified in incomplete Freund's adjuvant. The concentrations of the antibodies in sera were measured using enzyme-linked immunosorbent assays. Both linear and cyclic PmE-L induced high levels of antibodies against not only the immunized peptides but also autoantibodies against AQP5E and antibodies against PmE, a Pm homolog of AQP5E. In C57BL/6 mice; however, the cyclic form of PmE-L was more efficient than the linear form in inducing autoantibodies against AQP5E that contained a cyclic epitope. The levels of anti-PmE antibodies and anti-AQP5E autoantibodies showed a strong positive correlation (r = 0.95, p < 0.0005), suggesting molecular mimicry. Collectively, the mice produced anti-AQP5E autoantibodies in response to a PmAqp-derived peptide. This model proved to be useful for studying the mechanisms of autoantibody production by molecular mimicry.

A Study on Firing Risk Assessment of Film Manufacturing Process (필름제조 공정의 착화 위험성에 관한 연구)

  • Min, Se-Hong;Heo, Won-Il
    • Fire Science and Engineering
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    • v.25 no.3
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    • pp.107-112
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    • 2011
  • We have considered the fire hazard by the static in anti-static film manufacturing factory on this study. Solvents that the flash point as ethanol, methanol and iso-propyl alcohol is low are used on the manufacturing process of anti-static film, and the minimum ignition energy of these solvents is ignited easily despite less discharge energy form 0.16 mJ to 0.65 mJ. After the static electric potential produced on each of the manufacturing plants was measured, electric potential on films of paste board is measured form 17 kV to 20 kV. But this exceeds 5 kV, which is electrifiable of objective of nonconductor for fire & explode protection. Therefore, We figure out the fire hazard was high by a static discharge in anti-static film manufacturing factory.

Preparing Method and Physico-chemical Characteristics of $Terfenadine-{\beta}-Cyclodextrin$ Inclusion Compound (테르페나딘-${\beta}$-시클로덱스트린 포접화합물의 제조방법 및 물리화학적 특성)

  • Choi, Han-Gon;Ryu, Jei-Man;Yoon, Sung-June
    • Journal of Pharmaceutical Investigation
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    • v.27 no.3
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    • pp.219-223
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    • 1997
  • Terfenadine, antihistaminic drug, is poorly soluble in water. The purpose of this study is to investigate the possibility of using $terfenadine-{\beta}-cyclodextrin$ inclusion compound, instead of terfenadine, as the active substance of solid dosage form by improving the solubility, dissolution and anti-histaminic activity of terfenadine. The solubility and binding characteristics of $terfenadine-{\beta}-cyclodextrin$ complex in pH $1.2{\sim}6.8$ were investigated. Furthermore, the preparing method of $terfenadine-{\beta}-\;cyclodextrin$ inclusion compound was setting up and its physico-chemical characteristics such as DSC curve, solubility, dissolution and anti-histaminic activity were investigated. In conclusion, the solubility of terfenadine was increasing ${\beta}-cyclodextrin$ and with the decreasing pH. $Terfenadine-{\beta}-cyclodextrin$ inclusion compound, whose yield is almost 100%, was prepared by neutralization method. This inclusion compound was 200-times as soluble as terfenadine in pH 1.2-6.8. In addition, it had the faster dissolution and anti-histaminic activity than terfenadine. Therefore, it is used to the active substance of solid dosage form such as tablet and capsule in stead of terfenadine.

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Numerical Investigation of Anti-Diffusion Source Term for Free-Surface Wave Flow

  • Park, Sunho;Lee, Heebum;Rhee, Shin Hyung
    • Journal of Advanced Research in Ocean Engineering
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    • v.2 no.2
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    • pp.48-60
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    • 2016
  • Accurate simulation of free-surface wave flows around a ship is very important for better hull-form design. In this paper, a computational fluid dynamics (CFD) code which is based on the open source libraries, OpenFOAM, was developed to predict the wave patterns around a ship. Additional anti-diffusion source term for minimizing a numerical diffusion, which was caused by convection differencing scheme, was considered in the volume-fraction transport equation. The influence of the anti-diffusion source term was tested by applying it to free-surface wave flow around the Wigley and KCS model ships. In results, the wave patterns and hull wave profiles of the Wigley and KCS model ships for various anti-diffusion coefficients showed quite close patterns. While, the band width of the water volume-fraction values between 0.1 to 0.9 at the Wigley and KCS model hull surfaces was narrowed by considering the anti-diffusion term. From the results, anti-diffusion source term decreased free-surface smearing.

The research of anti-reflection coating using porous silicon for crystalline silicon solar cells (다공성 실리콘을 이용한 결정질 실리콘 태양전지 반사방지막에 관한 연구)

  • Lee, Jaedoo;Kim, Minjeong;Lee, Soohong
    • 한국신재생에너지학회:학술대회논문집
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    • 2010.06a
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    • pp.90.2-90.2
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    • 2010
  • The crystalline silicon solar cells have been optical losses. but it can be reduced using light trapping by texture structure and anti-reflection coating. The high reflective index of crystalline silicon at solar wavelengths(400nm~1000nm) creates large reflection losses that must be compensated for by applying anti-reflection coating. In this study, the use of porous silicon(PSi) as an active material in a solar cell to take advantage of light trapping and blue-harvesting photoluminescence effect. Porous silicon is form by anodization and can be obtained in an electrolyte with hydrofluoric. We expect our research can results approaching to lower than 10% of several reflectance by porous silicon solar cells.

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