Stationary random response analysis of linear fuzzy truss

Ma, J.,Chen, J.J.,Gao, W.,Zhao, Y.Y. Techno-Press 2006 Structural Engineering and Mechanics, An Int'l Jou Vol.22 No.4

A new method called fuzzy factor method for the stationary stochastic response analysis of fuzzy truss with global fuzzy structural parameters is presented in this paper. Considering the fuzziness of the structural physical parameters and geometric dimensions simultaneously, the fuzzy correlation function matrix of structural displacement response in time domain is derived by using the fuzzy factor method and the optimization method, the fuzzy mean square values of the structural displacement and stress response in the frequency domain are then developed with the fuzzy factor method. The influences of the fuzziness of structural parameters on the fuzziness of mean square values of the displacement and stress response are inspected via an example and some important conclusions are obtained. Finally, the example is simulated by Monte-Carlo method and the results of the two methods are close, which verified the feasibility of the method given in this paper.

2006-01-0310 A Design Approach Using Seamless Development Environments, SILS/RCP, for Real-Time Control Systems

Ma, J.,Youn, J.,Shin, M.,Sunwoo, M. AMERICAN TECHNICAL PUBLISHERS LTD 2006 S.A.E. transactions Vol.115 No.7

INTEGRATED DEVELOPMENT ENVIRONMENT FROM MODELING TO IMPLEMENTATION FOR AUTOMOTIVE REAL-TIME EMBEDDED CONTROL SYSTEMS

Ma, J.,Youn, J.,Shin, M.,Hwang, I.,SunWoo, M. The Korean Society of Automotive Engineers 2006 International journal of automotive technology Vol.7 No.3

Software-In-the-Loop Simulation(SILS) and Rapid Control Prototyping(RCP) are proposed as an integrated development environment to support the development process from system design to implementation. SILS is an environment used to simulate control systems with temporal behavior. RCP offers seamless phase shift from design to implementation based on automatic code generation. There are several toolsets that support control system design and analysis. A few of these tools generate the control software automatically. However, most of these design toolsets do not cover temporal behavior which appears after implementation. In earlier toolsets, the design and the implementation of a control system are considered as two separate processes which mean the conventional development process is not connected strictly. SILS/RCP environments work under an identical platform and use the same representation for system modeling. An integrated SILS/RCP environment makes it possible to design controllers under conditions similar to real execution during off-line simulation and to realize controllers in the early design phase. SILS/RCP environments integrate the design and implementation phases which reduce the time-to-market and provide greater performance-assured design. The establishment of SILS/RCP and the practical design approaches are presented.

Insight of Direct Search Methods and Module-Integrated Algorithms for Maximum Power Point Tracking (MPPT) of Stand-Alone Photovoltaic Systems

Ma, J.,Man, K.L.,Ting, T.O.,Lee, H.,Jeong, T.,Sean, J.-K.,Guan, S.-U.,Wong, P.W.H. SPRINGER-VERLAG 2012 ICHIT 2012 Vol.7513 No.-

Strength of the phonon-coupling mode in La2−xSrxCuO4, Bi2Sr2CaCu2O8+x and Y Ba2Cu3O6+x composites along the nodal direction

H.S. Ruiz,A. Badía-Majós 한국물리학회 2012 Current Applied Physics Vol.12 No.2

Despite the intensive efforts for determining the mechanism that causes high-temperature superconductivity in copper oxide materials, no consensus on the pairing mechanism has been reached. Recent advances in high resolution angle-resolved photoemission spectroscopies have suggested that a sizeable electron-phonon coupling exists as the principal cause for kinks in the dispersion relations (energy versus wave vector) of the electronic states. Here, we report on a systematic study about the influence of the electron-phonon coupling parameter “l” in the electronic quasiparticle dispersions of a wide family of CuO composites. In particular, the influence of the doping level in the cuprate families, La2-xSrxCuO4,Bi2Sr2CaCu2O8+x and Y Ba2Cu3O6+x over the dressing of the charge carriers, i.e., on the enhancement of the effective mass and the strength of the coupling mode for the nodal direction of the Fermi surface has been analyzed. Universal effects as the nodal kinks at low energies are theoretically reproduced,emphasizing the necessary distinction between the general electron mass-enhancement parameter l*and the conventional electron-phonon coupling parameter l. Our analysis shows a remarkable agreement between theory and experiment for different samples and at different doping levels. In fact, in LSCO family, the coupling constant l calculated consistently with the nodal kink dispersions, reproduces the observed critical temperatures Tc, the gap ratio 2D0/kBTc, and other parameters which have been studied from a wide set of natural and empirical equations which have been used along the last decades. It will be concluded that the strong renormalisation of the band structure can be explained in terms of the phonon coupling mode, and must therefore be included in any microscopic theory of superconductivity,even for those materials in which the contribution to the pair formation can be less dominant. Nevertheless,in more anisotropic structures, simulations reducing the Coulomb effects to encourage the phonon mechanism reveal as seems unavoidable to consider additional coupling modes that justify the higher critical temperatures observed in BSCCO and YBCO samples.

INDIA CHINA RELATIONS Growing Tensions?

Maj Gen Dipankar Banerjee 제주평화연구원 2009 JPI Peace Net Vol.2009 No.10

Induced Optical Activity of DNA-Templated Cyanine Dye Aggregates: Exciton Coupling Theory and TD-DFT Studies

Maj, Michał,Jeon, Jonggu,Gó,ra, Robert W.,Cho, Minhaeng American Chemical Society 2013 The journal of physical chemistry. A, Molecules, s Vol.117 No.29

<P>Certain cyanine dye molecules have been observed to self-assemble in DNA templates to form large chiral aggregates, which exhibit induced circular dichroism. The structure and circular dichroism (CD) of one such system, aggregates of a cationic DiSC<SUB>2</SUB>(5) cyanine dye, are investigated using the time-dependent Kohn–Sham density functional theory (TD-DFT) and exciton coupling model. A series of TD-DFT calculations on the aggregates with one, two, and four dye molecules clearly shows the onset of CD induced by the helically twisted structure compatible with the minor groove of DNA templates. More simplified exciton coupling model analysis successfully reproduces the major positive Cotton effect observed in the experiment as well as the TD-DFT calculations, but it is unable to capture minor features of the CD spectrum that are closely related to absolute configurations of constituent dyes in the complex. We assess the performance of various methods used for evaluation of the electronic coupling energies between interacting chromophores. Our results confirm that the interchromophore interactions in cyanine dye aggregates are primarily electrostatic in nature and indicate that the exciton coupling model is adequate for studying induced CD of self-assembled aggregates of cyanine dye molecules.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpcafh/2013/jpcafh.2013.117.issue-29/jp309807y/production/images/medium/jp-2012-09807y_0006.gif'></P>

β-Isocyanoalanine as an IR probe: comparison of vibrational dynamics between isonitrile and nitrile-derivatized IR probes

Maj, Michał,Ahn, Changwoo,Kossowska, Dorota,Park, Kwanghee,Kwak, Kyungwon,Han, Hogyu,Cho, Minhaeng The Royal Society of Chemistry 2015 Physical chemistry chemical physics Vol.17 No.17

<P>An infrared (IR) probe based on isonitrile (NC)-derivatized alanine <B>1</B> was synthesized and the vibrational properties of its NC stretching mode were investigated using FTIR and femtosecond IR pump–probe spectroscopy. It is found that the NC stretching mode is very sensitive to the hydrogen-bonding ability of solvent molecules. Moreover, its transition dipole strength is larger than that of nitrile (CN) in nitrile-derivatized IR probe <B>2</B>. The vibrational lifetime of the NC stretching mode is found to be 5.5 ± 0.2 ps in both D<SUB>2</SUB>O and DMF solvents, which is several times longer than that of the azido (N<SUB>3</SUB>) stretching mode in azido-derivatized IR probe <B>3</B>. Altogether these properties suggest that the NC group can be a very promising sensing moiety of IR probes for studying the solvation structure and dynamics of biomolecules.</P> <P>Graphic Abstract</P><P>An infrared (IR) probe based on isonitrile (NC)-derivatized alanine <B>1</B> was synthesized and the vibrational properties of its NC stretching mode were investigated using FTIR and femtosecond IR pump–probe spectroscopy. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c5cp00454c'> </P>

Isonitrile as an Ultrasensitive Infrared Reporter of Hydrogen-Bonding Structure and Dynamics

Maj, Micha,Ahn, Changwoo,Basiak, Bartosz,Kwak, Kyungwon,Han, Hogyu,Cho, Minhaeng American Chemical Society 2016 The Journal of physical chemistry B Vol.120 No.39

<P>Infrared (IR) probes based on terminally blocked beta-isocyanoalanine (AlaNC) and p-isocyanophenylalanine (PheNC) amino acids were synthesized. These isonitrile (NC)-derivatized compounds were extensively characterized by FTIR and femtosecond IR pump-probe spectroscopies, and a direct comparison was made with popularly used nitrile (CN)- and azide (N-3)-derivatized analogs. It is shown that the isonitrile stretch frequency exhibits extremely high sensitivity to hydrogen-bonding interactions. In addition, the IR intensity of the isonitrile group is much higher than that of the nitrile group and almost as intense as that of the azido group. Furthermore, its vibrational lifetime is much longer than that of the nitrile and azido groups. To elucidate the origin of such a high H-bond sensitivity and IR intensity observed for isonitrile, extensive quantum chemical calculations were performed. It is shown that the Coulombic contributions to the vibrational frequency shifts of the isonitrile and nitrile stretch modes have opposite signs but similar magnitudes, whereas the contributions of exchange repulsion and charge delocalization to their frequency shifts are comparable. Therefore, the isonitrile stretch frequency is much more sensitive to H-bonding interactions because the blue-shifting exchange-repulsion effects additionally enforced by such electrostatic effects. It is also shown that the much higher IR intensity of the isonitrile group compared to that of the nitrile group is due to the configuration reversal of the atomic electronegativity between the NC and CN groups. Owing to these features, we believe that isonitrile is a much better IR reporter of H-bonding structure and dynamics than the widely used nitrile and azide.</P>

Microstructure and Strain-Stress Analysis of the Dynamic Strain Aging in Inconel 625 at High Temperature

P. Maj,J. Zdunek,J. Mizera,K. J. Kurzydlowski,B. Sakowicz,M. Kaminski 대한금속·재료학회 2017 METALS AND MATERIALS International Vol.23 No.1

Serrated flow is a result of unstable plastic flow, which occurs during tensile and compression tests on some dilute alloys. This phenomenon is referred as the Portevin Le-Chatelier effect (PLC effect). The aim of this research was to investigate and analyze this phenomenon in Inconel 625 solution strengthened superalloy. The tested material was subjected to tensile tests carried out within the temperature range 200-700 °C, with three different strain rates: 0.002 1/s, 0.01/s, and 0.05 1/s and additional compression tests with high deformation speeds of 0.1, 1, and 10 1/s. The tensile strain curves were analyzed in terms of intensity and the observed patterns of serrations Using a modified stress drop method proposed by the authors, the activation energy was calculated with the assumption that the stress drops’ distribution is a direct representation of an average solute atom’s interaction with dislocations. Subsequently, two models, the standard vacancy diffusion Bilby-Cottrell model and the realistic cross-core diffusion mechanism proposed by Zhang and Curtin, were compared. The results obtained show that the second one agrees with the experimental data. Additional microstructure analysis was performed to identify microstructure elements that may be responsible for the PLC effect. Based on the results, the relationship between the intensity of the phenomenon and the conditions of the tests were determined.