bluuebunny/crossref_metadata_2025_split huggingface dataset:
A method of automatic image reconstruction from holograms by a homomorphic system of logarithmic transform type
Authors: Aoki Yoshinao , Kuniyoshi Toshiharu , Amber Handoko , Takahashi Yukinobu 
Published: July 2007

AbstractA new computer technique for automatic image reconstruction from holograms is proposed. The technique is based on the idea of filtering in a homomorphic system of the logarithmic‐transform type. The theoretical analysis and computer simulation were conducted using the proposed technique. The technique is based on the principle that the odd function of the phase term of the Fourier transform of a real‐number function representing an object can be separated from the even function of the phase term of the propagation function representing the wave propagation. Accordingly, in the proposed method of image reconstruction the image plane can be determined automatically with only the given hologram data, even if information on the distance parameter is not obtained in the holo‐gram recording stage. To simulate the proposed technique on a computer, data of a Fresnel‐transformed hologram of complex number were generated numerically, with the assumption that a plane object is illuminated by a plane wave and image reconstruction was conducted by separating the even function of the phase term of the object function from the propagation function to demonstrate the validity of the proposed method. The possibility of automatic image reconstruction and problems of the proposed technique are discussed and the conventional method is compared with the result of the computer simulation.
Deep heating technique for hyperthermia
Authors: Amemiya Yoshifumi , Terada Noriyoshi 
Published: July 2007

AbstractThe heating of cancers, which are located far below the body surface, results in unwanted heating of the body surface. At 1000 MHz the penetration depth of the microwave power is 2 cm, and a strong cooling of the body surface is required while heating the deep cancer. This paper proposes an arrangement of electric current sources which permits a local heating deep in the human body and for which the heating potential and the electric field distribution in the body have been calculated. This method avoids the strong cooling of the body surface, and the electric power, which is required theoretically, is found to be reasonable.
B lymphocyte deficiency in IgH‐transgenic rabbits
Authors: Jasper Paul J. , Rhee Ki‐Jong , Kalis Susan L. , Sethupathi Periannan , Yam Pi‐Chen , Zhai Shi‐Kang , Knight Katherine L. 
Published: July 2007

AbstractWe developed IgH‐transgenic rabbits carrying a productive VDJ‐Cμ Tg and found the rabbits were B cell‐deficient, with a 50–100% reduction in serum IgM and IgG levels. The bone marrow of newborn Tg rabbits contained severely reduced levels of preB cells and almost no B cells. The few preB cells present in the bone marrow were large, cycling cells that expressed the VDJ‐Cμ Tg, indicating that the block in B cell development likely occurred at or before the transition from large (early) preB to small (late) preB cells. By immunoprecipitation, the Tg μ‐chain paired with VpreB and λ5, suggesting that the B cell deficiency is not due to an inability to form a preB cell receptor. Despite the block in B cell development, a few B cells, expressing predominantly endogenous μ‐chains, began the second stage of development in GALT. B cells were localized in and beneath the follicle‐associated epithelium of GALT prior to B cell follicle formation, suggesting to us that B cell follicle formation is initiated near the follicle‐associated epithelium, possibly through contact with intestinal microbiota. These IgH‐Tg rabbits should provide a useful model for studies of B cell development both in bone marrow and in GALT.
Proliferative activation up‐regulates expression of CD4 and HIV‐1 co‐receptors on NK cells and induces their infection with HIV‐1
Authors: Harada Hideki , Goto Yumi , Ohno Tadao , Suzu Shinya , Okada Seiji 
Published: July 2007

AbstractNK cells play important roles in immune surveillance against malignancy and virus‐infected cells. NK cell functions are affected in patients infected with HIV‐1; however, whether there is direct interaction between NK cells and HIV‐1 remains controversial. In this study the expression of CD4, an important receptor for HIV‐1, was up‐regulated on NK cells co‐cultured with an NK cell‐selective stimulating cell line, HFWT, and rIL‐2. Although the level of CD4 was lower on NK cells than on CD4+ T cells, expression of the HIV‐1 co‐receptor CCR5 was clearly up‐regulated on CD4+ NK cells. CD4+ NK cells expressed higher levels of HLA‐DR and CD25 than CD4– NK cells, suggesting that they were highly activated. Cell‐free HIV‐1 could not infect the NK cells, but NK cells were infected when co‐cultured with HIV‐1‐infected T cells. Using this co‐culture system, we can better understand how HIV‐1 infects NK cells and how NK cell functions are affected in AIDS.
Syntheses, Characterization, and Luminescent Properties of Monoethylzinc Complexes with Anilido–Imine Ligands
Authors: Su Qing , Gao Wei , Wu Qiao‐Lin , Ye Ling , Li Guang‐Hua , Mu Ying 
Published: July 2007

AbstractThe syntheses of three anilido–imine ligands of the general formula ortho‐C6H4(NHAr′)(CH=NAr″ [Ar′ = 7‐(2,4‐Me2)C9H4N, Ar″ = 2,6‐Me2C6H3 (2a); Ar′ = 7‐(2,4‐Me2)C9H4N, Ar″= 2,6‐Et2C6H3 (2b); Ar′ = 7‐(2,4‐Me2)C9H4N, Ar″= 2,6‐iPr2C6H3 (2c)] and four zinc(II) complexes of the general formula [ortho‐C6H4(NHAr′)(CH=NAr″)]ZnEt [Ar′ = 7‐(2,4‐Me2)C9H4N, Ar″= 2,6‐Me2C6H3 (3a); Ar′ = 7‐(2,4‐Me2)C9H4N, Ar″= 2,6‐Et2C6H3 (3b); Ar′ = 7‐(2,4‐Me2)C9H4N, Ar″ = 2,6‐iPr2C6H3 (3c); Ar″ = 2,6‐Me2C6H3, Ar″ = 2,6‐iPr2C6H3 (3d)] are described. The complexes were synthesized from the reaction of ZnEt2 with corresponding ligands 2 by alkane elimination. All compounds were characterized by elemental analysis and 1H and 13C NMR spectroscopy. The molecular structures of compounds 2a, 2b, 3b, and 3c were determined by single‐crystal X‐ray crystallography. The X‐ray analysis reveals that complexes 3b and 3c exist in the dimeric form with the N atom in the quinolyl ring coordinating to the other Zn atom to make the Zn atoms four coordinate. Luminescent properties of ligands 2a–2d and complexes 3a–3d in both solution and the solid state were studied. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
An Approach to the Synthesis of Silicon Carbide Nanowires by Simple Thermal Evaporation of Ferrocene onto Silicon Wafers
Authors: Niu Jun‐Jie , Wang Jian‐Nong 
Published: July 2007

AbstractScales of silicon carbide nanowires (SiC‐NWs) with high quality were synthesized by direct thermal evaporation of ferrocene onto silicon wafers at high temperature. Ferrocene decomposed into iron and carbon, which was subsequently treated with silicon to form SiC‐NWs at high temperature. The SiC‐NWs possess small diameters of ≈ 20 nm and lengths of several μms. Furthermore, the samples show a uniform morphology, crystalline structure, and a very thin oxide layer. The main crystal direction of [111] was confirmed by high‐resolution field‐emission‐transmission electron microscopy (HR‐FETEM). The Raman scattering spectra showed two peaks at ≈ 796 (TO) and ≈ 980 cm–1 (LO) with varying intensity ratios at different positions. The band line fluctuation was contributed to the Raman selection rules. With reference to the experimental results, we suggested a tentative growth model according to the vapor–liquid–solid (VLS) mechanism. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Facile Synthesis of Aluminum‐Bridged [3,3,3]Cyclophanes by Hydroalumination
Authors: Uhl Werner , Hepp Alexander , Matar Madhat , Vinogradov Andrej 
Published: July 2007

AbstractThe reaction of 1,3,5‐tris(3,3‐dimethyl‐1‐butinyl)benzene C6H3(C≡C–CMe3)3 with the dialkylaluminum hydrides HAl(CMe3)2 and HAl(CH2CMe3)2 gave the addition of one Al–H bond to each C–C triple bond (hydroalumination). Spontaneous condensation by the release of the corresponding trialkylaluminum derivatives afforded [3,3,3]cyclophane derivatives 6 and 7 in which three tricoordinate Al atoms are in the bridging positions between two functionalized benzene rings. The aluminum atoms behave as Lewis acids, and treatment with thf yielded adduct 6·3thf. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Proton NMR Study of Low‐Spin meso‐Unsubstituted β‐Substituted Alkyl Iron Porphyrins: Remarkable Influence of Peripheral Substitution on Spin Density
Authors: Juillard Sandrine , Bondon Arnaud , Simonneaux Gérard 
Published: July 2007

AbstractParamagnetic NMR spectroscopy was used to characterize the influence of small alkyl groups on the spin density of a series of high‐spin and low‐spin iron(III) porphyrins. Assignment of the resonances was obtained by using a variety of NMR techniques including heteronuclear multiple bond correlation and saturation transfer experiments. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Tetranuclear (Phosphane)(thiolato)gold(I) Complexes: Synthesis, Characterization and Photoluminescent Properties
Authors: Fernández Eduardo J. , Laguna Antonio , López‐de‐Luzuriaga José M. , Monge Miguel , Montiel Manuel , Olmos M. Elena , Puelles Raquel C. , Sánchez‐Forcada Eva 
Published: July 2007

AbstractThe reactions of the tetraphosphane donor ligand (Ph2PCH2)2NCH2CH2N(CH2PPh2)2 with the gold precursors [AuCl(tht)] or [Au(C6F5)(tht)] (tht = tetrahydrothiophene) leads to complexes [Au4R4{(Ph2PCH2)2NCH2CH2N(CH2PPh2)2}] [R = Cl (1) or C6F5 (2)]. Further substitution of the chlorine atoms in 1 by the corresponding 4‐substituted benzenethiolates gives rise to the tetranuclear (phosphane)(thiolato)gold(I) complexes [Au4(S‐C6H4‐X)4{(Ph2PCH2)2NCH2CH2N(CH2PPh2)2}] [X = F (3), MeO (4), Me (5) and NO2 (6)]. Complexes 2 and 4 were characterized by X‐ray diffraction studies showing Au···Au interactions in the case of complex 4. Complexes 3–6 display intense emissions in the solid state at 77 K with lifetimes in the microsecond range. The observed phosphorescent emissions are attributed to metal‐to‐ligand charge‐transfer transitions. Nevertheless, the influence in the emission energies of gold–gold interactions or the contribution of the substituent in the 4‐position of the benzenethiolate ring to the excited state cannot be neglected. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
A new pst‐weighting filter for the flickermeter in the frequency domain
Authors: Amarís H. , Usaola J. 
Published: July 2007

AbstractThis paper presents a new filter for the Flickermeter in the frequency domain that allows a fast estimation of the Pstshort‐time flicker parameter. The power spectrum of the signal is weighted with the new Pst‐weighting filter and the Pstparameter may be deduced directly. The Flickermeter structure has been tested with the IEC‐Flickermeter recommendations and it presents a good behaviour in the whole bandwidth of O Hz to 35 Hz even in very low frequencies. The filter model has been deduced by using identification tools in the frequency domain. The advantages of the Flickermeter methodology in the frequency domain are studied.
Design of current and speed controllers for slip energy recovery induction motor drive using root‐locus technique
Authors: Faiz J. , Barati H. , Akpinar E. 
Published: July 2007

AbstractThe most common problem of the slip recovery system is stabilizing the system under power system disturbances, such as the change of supply voltage. Two back‐to‐back proportional‐plus‐integral (PI) controllers are used in a closed‐loop control system, to control the DC‐link current and speed. In order to estimate parameters of the controllers using root‐locus technique, a non‐linear transient model of the drive is linearized around the steady‐state operating point. The performance of the drive in the presence of disturbance signals is studied and finally the eliminating speed error signal and the continuous variations of the inverter‐firing angle are illustrated.
Research note: Dielectric diagnosis of water content in transformer insulation systems
Authors: Küchler A. , Bedel T. 
Published: July 2007

AbstractThis paper describes dielectric measurements at transformer insulation models made of Transformerboard barriers and oil channels. It was intended to quantify the water content in barriers and to distinguish the influences of water and geometric structure. Recovery‐voltage measurements (RVM) did not show a clear correlation with water content, probably because of “parasitic” influences like oil parameters, geometry and parallel resistances. Better correlations were found for insulation resistances i. e. for polarization currents. Network simulations show that common circuits ‐ normally used for homogeneous materials ‐ are not able to explain the measurements. Therefore circuits had to be adapted to the geometric structures of the insulation. Thereby it could be shown that recovery voltages are dominated by interfacial polarisation between oil channels and barriers. Signals are strongly dependent on oil resistivities, possibly “masking” the influence of water in the barriers.
Enhanced ac power‐flow solutions for reliability analyses
Authors: Sorg A. , Heckmann W. , Weber Th. , Wellssow W. H. 
Published: July 2007

AbstractThe paper presents an advanced Newton‐Raphson power‐flow algorithm for reliability evaluation with special regard to the prevention of non‐convergent situations. Remedial actions in order to relieve violations of operational constraints and some generation rescheduling functions are considered. Included is a reliability analysis for a sample power system in order to compare the resulting reliability indices using different power‐flow algorithms.
Unit commitment at frequency security condition
Authors: Lei X. , Lerch E. , Povh D. 
Published: July 2007

AbstractIn island grids and weakly interconnected power systems, the loss of a large proportion of generation will cause the system frequency to fall dramatically. In order to ensure a stable operation with the lowest impact to the system, the disturbed power balance must be equalized within a short specified time by activating the second‐reserve of on‐line units or by load shedding or both. Unit commitment procedures shall consider these factors to ensure a reliable power supply while minimizing the fuel costs. This paper presents a unit commitment procedure taking the frequency security condition of systems into account. The procedure commits and optimizes units, calculates necessary second‐reserve capability, and allocates them among the available on‐line units. Parallel to the minimization of daily fuel costs, a specified frequency minimum following the loss of generation is employed as a criterion for maintaining system security. A case study on typical island systems with a large number of different units is demonstrated using the proposed procedure. Results from the study validated robust performance of the proposed procedure that minimizes fuel costs while maintaining frequency security condition. This paper considers only the frequency security condition to be handled. However, it can also be extended with other criteria such transmission capability during transient conditions of interconnected systems.
Non‐linear approaches for reducing large power systems
Authors: Lei X. , Buchholz B. , Ruhle O. , Kulicke B. , Menze A. 
Published: July 2007

AbstractIssues on the establishment of equivalent networks are becoming essential for the deregulated power market. This paper presents a comprehensive tool for network reduction of large power systems. Through integrating different methodologies into a simulation program, the dynamic equivalent can be established by adopting one common database. With a readily integrated modified Gauss‐Newton algorithm, network reduction can be executed under the dynamic conditions either in the time domain or in the frequency domain in coping with nonlinear nature of the system involved. Furthermore, a novel algorithm based on dynamic coherency approach implemented readily into the simulation program is also presented. This novel approach determines coherent generators on non‐linear basis in the time domain using the cross correlation technique, taking dynamic characteristics of the system involved into consideration. Two case studies are presented in this paper. Each of the non‐linear approaches presented is applied for one of the case studies as application example. The results achieved validate the functionality of the approaches presented.
Power flow solution by a complex admittance matrix method
Authors: Benato R. , Paolucci A. , Turri R. 
Published: July 2007

AbstractThe paper describes a newly developed algorithm for power flow solution based on a complex admittance matrix. The conciseness and close‐to‐reality iterative procedure make the method extremely attractive for self‐made software implementation. The complex algorithm approach enables network connections, loads, generators, controlled bus voltages, including slack bus, to be considered in a single complex matrix. The power flow solution is achieved with iterations in complex form without the need of real/imaginary decomposition. The method has shown to have advantages over other traditional and available methods in terms of accuracy and convergence also in highly ill‐conditioned cases. The cpu‐time is comparable and sometimes competitive with those derived from Newton‐Raphson methods.
Determination of location of series compensation devices using fuzzy decision making
Authors: Bagriyanik M. , Dag H. 
Published: July 2007

AbstractThis paper presents a method to place the thyristor controlled series capacitor (TCSC) in transmission lines using fuzzy decision making method. The indices used for making a decision are those that TCSC affects the most. Amount of increase in operation limit boundary, amount of voltage drop, level of short circuit current, and the amplitude of line reactance are some of the indices that can be used when making a fuzzy decision to place a device in power system. TCSC placement is done for three reasons: improvement of voltage stability, improvement of transient stability, and reduction of total reactive power loss. By using fuzzy decision making we intend to realize the three goals above at the same time (or attain as much improvement /reduction as possible). The method is applied to some of the standard test cases and the results are provided.
Power flow studies of a large practical power network with embedded facts devices using improved optimal multiplier newton‐raphson method
Authors: Xiao Y. , Song Y. H. 
Published: July 2007

AbstractIn this paper, an improved optimal multiplier Newton‐Raphson (OMNR) power flow method is presented for power flow studies of ill‐conditioned large power system with embedded Flexible AC Transmission Systems (FACTS) devices. Power injection models (PIMs) of two typical FACTS devices, Phase Shifter (PS) and Unified Power Flow Controller (UPFC), are derived in rectangular form. After detailed analysis, a defect of the original OMNR method is identified and an improved version is presented. Incorporating the derived FACTS power injection models into the improved OMNR power flow program, the impacts of FACTS devices on power system control have been fully tested on the U.K. National Grid Company (NGC) system. The results clearly illustrate the effectiveness of the proposed approach.
Advanced voltage dependent dynamic programming algorithm for the optimization of shunt capacitors in radial distribution systems
Authors: Sarić A. T. , Ćalovićl M. S. , Djukanović M. B. 
Published: July 2007

AbstractThis paper presents a new voltage dependent model for optimal reactive compensation planning of radial distribution systems. It is of combinatorial type, with non‐linear and non‐differentiable criterion function, including nonequality constraints. The problem solution consists of an effective accelerated search, based on the dynamic programming. Two different search procedures are proposed. The first procedure employs normalized simultaneous load duration curves of consumer's nodes, arranged in decreased sequence and the second one considers the case of non‐simultaneous and unarranged load diagrams. The model is tested on two characteristic radial distribution systems. It exhibited better results regarding savings, than previously proposed methods applied on the same test systems.
Optimization and minimization of torque ripple in A.C machines supplied by V.S.I
Authors: Rekioua T. , Rekioua D. , Laporte B. , Benmahammed K. 
Published: July 2007

AbstractIn this paper, the design of a position sensor for voltage source inverter (V.S.I) fed alternating current (A.C) machines is presented. This system aims at suppressing undesirable voltage harmonics and hence minimizing electromagnetic torque ripple. The optimized pulse width modulation (P.W.M) technique is used as a base for the design of this position sensor. In comparison with the classical system, the undesirable harmonics are eliminated directly by the position sensor control output signal and not from the inverter output voltage waveforms. Thus, the obtained inverter control circuit is a very simple design and there is no need for microprocessor nor for specialized P.W.M integrated circuits use for its implementation. The obtained simulation results are compared to the practical ones, in the case of a self controlled synchronous machine.
Feeder reconfiguration employing simulated annealing for distribution systems
Authors: Su C.‐T. , Lee C.‐S. , Huang L.‐L. 
Published: July 2007

AbstractThis paper presents an effective method to feeder reconfiguration for reliability improvement, loss reduction, and voltage profile enhancement. Feeder reconfiguration is often accomplished by operating the sectionalizing switches placed along a feeder and the tie switches connecting feeders. Two reliability indices, system average interruption frequency index (SAIFI) and system average interruption duration index (SAIDI), are employed. To obtain the optimal solution, the simulated annealing technique is applied. The idea of this research is to identify beneficial load transfers, such that the objective function composed of SAIFI, SAIDI. and power loss is minimized and voltage quality constraint is satisfied. The application of the proposed approach is demonstrated by using a practical secondary substation of Taiwan Power Company (TPC). Simulation results show that the method is especially effective in reliability improvement, but effect of power loss reduction is not significant.
Factors affecting the dynamics of wire particles in gas‐insulated systems
Authors: Metwally I. A. , Abdel‐Rahim A. 
Published: July 2007

AbstractThis paper introduces a theoretical study of the significant factors that affecting the dynamics of wire particles in a horizontal coaxial gas‐insulated transmission line (GITL) and/or gas‐insulated switchgear (GIS) systems. The dynamics of the particle is investigated using a computational algorithm and under different voltage waveforms, gas pressures and coating thicknesses. The simulated voltage waveforms are the 60 Hz AC, single and successive switching impulses (SI), and bipolar‐oscillatory and damped impulses. All the applied voltage waveforms are simulated with and without the DC prestress, except for the AC case. These voltages represent the actual waveforms that occur in practice. The present work highlights the dangerous situations of the particle dynamics and their methods of mitigation. Moreover, the investigated dynamic behaviours of such defect under AC energization give excellent signs for the recognition by the acoustic detection technique.