bluuebunny/crossref_metadata_2025_split huggingface dataset:
ChemInform Abstract: Nuclear Magnetic Resonance Spectroscopy of Calcium Phosphates
Authors: YESINOWSKI J. P. 
Published: July 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Bridged Silylene and Germylene Complexes
Authors: OGINO H. , TOBITA H. 
Published: July 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Organometallic Complexes in Nonlinear Optics I: Second‐Order Nonlinearities
Authors: WHITTALL I. R. , MCDONAGH A. M. , HAMPHREY M. G. , SAMOC M. 
Published: July 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A Radical Account of “Oxygenated Fenton Chemistry”
Authors: MACFAUL P. A. , WAYNER D. D. M. , INGOLD K. U. 
Published: July 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Chemistry of anti HIV‐1 Active Calophyllum Coumarins
Authors: ISHIKAWA T. 
Published: July 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Structural Basis of Protein Kinase C Activation by Tumor Promoters
Authors: KISHI Y. , RANDO R. R. 
Published: July 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Inorganic Mimics of Ribonucleases and Ribozymes: From Random Cleavage to Sequence‐Specific Chemistry to Catalytic Antisense Drugs.
Authors: TRAWICK B. N. , DANIHER A. T. , BASHKIN J. K. 
Published: July 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Cleavage of Nucleic Acids by Bleomycin.
Authors: BURGER R. M. 
Published: July 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Chemistry of Glycosylases and Endonucleases Involved in Base‐Excision Repair.
Authors: DAVID S. S. , WILLIAMS S. D. 
Published: July 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Development of Platin‐calixarenes. Trapping Platinum Hydrides in Molecular Cavities
Authors: WIESER‐JEUNESSE C. , MATT D. 
Published: July 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Nonlinear oscillations due to nonlinear Arc characteristics
Authors: Schötzau H. J. , Kneubühl F. K. 
Published: July 2010

AbstractThe negative U‐I‐characteristic of a high‐pressure arc causes unstable current oscillations in selected LC‐networks. In the present paper three different types of oscillations are analyzed. The relevant nonlinear differential equations are solved by numerical and analytical methods as well as by graphical integration procedures. Two types of stable oscillations occur. They can be represented either by stable sinusoidal or almost triangular waveforms or by a Van der Pol oscillation. The third kind of oscillation is unstable and grows exponentially only for small amplitudes whilst it increases considerably faster for larger amplitudes. Our results agree with the experimentally observed features of arcs in electrical power networks.
Optimisation of the damping resistance of synchronous machines using a quadratic performance criterion
Authors: Haager W. 
Published: July 2010

AbstractStarting from a simplified model of the salientpole engine in the form of the analytically computed transfer function the damping resistance is optimized. The applied performance criterion provides a formula for that damping resistance, at which rotor hunting, occurring for example at changes of the load, is damped down in the best possible way.
Discrete‐time model of an induction motor
Authors: Böcker J. 
Published: July 2010

AbstractIf a state‐space observer of a continuous‐time process is to be realized on a sampling microprocessor system, a discrete time model of the process is needed. Time‐varying continuous‐time parameters require the on‐line computation of the discrete‐time model. For this purpose numerical integration algorithms are used to get an approximate model instead of the exact model in discrete‐time. For the model of an induction motor it is pointed out that the often‐used first‐order algorithm of Euler (RK1) is crucial. Even the choice of the continuous‐time differential equation system, which has to be discretized, influences the quality of the discrete‐time approximation in a decisive manner. On the one hand even stability problems appear while on the other hand, by choosing the equation system in a skilful manner, one obtains a simple and accurate discrete‐time model, which can be used for microprocessor implementations.
Three‐dimensional electric field analysis using segment arrangement of high‐ voltage apparatus component based on charge simulation method
Authors: Okubo H. , Kito Y. 
Published: July 2010

AbstractThis paper describes the development of three‐dimensional electric field analysis by using segment method which enables to calculate the electric field with high accuracy and with enhanced efficiency. In the segment method, an electrode configuration of high voltage apparatus is simulated by arrangement of several kinds of small components which are defined as segments. In the calculation, a charge simulation method is used. In this paper, the fundamental construction and arrangement parameter of segments are described. On the basis of the application results, the calculation accuracy is discussed.
Study and application of a digital speed control in a DC brushless drive
Authors: Dallago E. , Sassone G. 
Published: July 2010

AbstractIn this paper the study and the realization of a digital speed control in a DC brushless drive are described. A typical industrial DC brushless drive with analog speed control as a starting point is considered in this work. After the main characteristics of the electrical drive considered are given, the problems associated with the realization of the digital speed control are examined. The procedures and the solutions adopted to realize the microprocessor‐based control system are described, and the results obtained from experimentation are examined. Finally, considerations on the usefulness and advantages of a digital solution for control in comparison with the analog version are presented.
New algorithms for earthfault distance protection in insulated and compensated networks
Authors: Igel M. , Koglin H.‐J. , Schegner P. 
Published: July 2010

AbstractThrough the analysis of transient signals after the occurrence of an earthfault it is possible to evaluate fault direction and fault distance. The faulty line is simulated by using a three phase Tl‐model. The result is a differential equation of a higher order, which only consists of voltages and currents, which are measured at the installation point of the relay. If the capacities of the part of the network without earthfault are considerably larger than those of the faulty line, the line capacities of the faulty line can be ignored in the differential equation. This results in afirst‐jorder differential equation, which can be solved by integration in the time domain. A second algorithm takes the line capacities into consideration. The derivatives of the input signals are calculated in the frequency domain. A third algorithm calculates the equivalent fault inductivity in the frequency domain by complex division. The last algorithm deals with the line capacities by using correction factors. The mode of operation of the earthfault distance algorithms presented here will be shown with the example of a 22‐kV‐overhead line network.
New current balancing and power factor improving scheme
Authors: Gagliardi F. , Lauria D. , Luciano A. M. , Tironi E. , Ubezio G. 
Published: July 2010

AbstractThis paper describes the main properties of a new scheme for current balancing and power factor improving of two unbalanced loads. The scheme employs a forced switching two‐phase inverter whose switching output voltage is achieved with PWM modulation. The proposed configuration has safe and reliable operation, permitting furthermore to minimize the harmonic interference transmitted to the network. In the first part of the paper the operating principles of the scheme are carried out and in the second one a possible control strategy is described.
Optimal re‐configuration of distribution network for loss reduction using non‐linear programming
Authors: Augugliaro A. , Dusonchet L. , Mangione S. 
Published: July 2010

AbstractThis paper deals with the problem of optimizing radially operated meshed networks in order to obtain the radial configuration which satisfies the condition of minimum power losses and also the technical constraints normally adopted for such systems. After reporting the state of art on distribution network reconfiguration, the mathematical approach to the solution of the normal state re‐configuration for loss reduction is presented, together with the non‐linear optimization model. In the proposed model, sectionalizing switches are simulated as variable resistances. By starting from the meshed network obtained by closing all switches optimal solution is found directly; the solution is addressed towards the radial structure by some suitable constraints. To solve the problem, a suitable non‐linear programming package is used. Finally some results referring to a hypothetical medium voltage test network are reported.
Calculation of temperatures in enclosed switchgears with regard to the closed circulation flow of gaseous dielectrics
Authors: Lippert T. , Böhme H. 
Published: July 2010

AbstractIn connection with the temperature calculation for enclosed gas isolated switchgears (especially in the case of constant load) problems arise at the mathematical modelling of the convective heat transmission, when the vertical temperature difference in the gas is important due to the circulating flow. In this case the model of the thermal network analogous to a simple electrical network is not applicable immediately. Therefore the convective heat flow within the switchgear will be determined by the calculation of the thermal flow field basing on the physical fundamental equations exclusively. A simple example demonstrates in which way the result of the field calculation will be inserted to the model of thermal network. For example the exact consideration of the convective flow field has significant influence on the result of the temperature calculation.
Trends in developing electrical actuators
Authors: Gutt H.‐J. 
Published: July 2010

AbstractElectrical actuators are equipments for the conversion of electrical energy and signals into mechanical forces and movements. Sensors ‐ used in connection with these actuators ‐ are devices for the conversion of electromagnetic or mechanical units into electromagnetic signals. Both ‐ actuators and sensors ‐ become so intensively integrated, that the behaviour of electrical actuators is defined by the kind of sensor‐controlling (and no more by its construction). Further trends are tried to be quantified by technical development curves versus the time, the trends to higher actuator speed and its limits, to intensive cooling and high‐temperature superconductivity as well as to further permanent‐magnet materials and last not least to intelligent electrical actuator systems.
Iteration‐free calculation of the transient voltage breaking in industrial and power plants
Authors: Cupsa A. 
Published: July 2010

AbstractEach switching operation in auxiliary systems causes overcurrents, which often entail large voltage breakings at the terminals of electric motors. In order to be able to forecast whether these motors will continue to run or run up, it is interesting to calculate the so‐called transient voltage breaking, i. e. to calculate the terminal voltages which occur within seconds after the short subtransient starting or changeover rush current. This paper describes an analytic method for this calculation, with the help of which the voltage breakings can be precisely determined without extensive iterations and without not allowed assumptions.
25 kW/200 khz parallel resonant converter for induction heating
Authors: Dede E. J. , González J. V. , Linares J. A. , Jordán J. , Ramírez D. , Maset E. 
Published: July 2010

AbstractThe features, technology and construction of a transistorized generator for induction heating operating over the 50 kHz … 200 kHz frequency range are presented. This new type of generator with 25 kW output power allows to replace the electronic tube generators in most part of their applications. The most outstanding advantages of this new generator in respect of tube generators are: more energy efficiency, extended service life, reduced size, separated mounting of heating station and generator. The generator incorporates an automatic frequency tracking system which allows to operate without any adjustments over a wide frequency range.
Damping of electromechanical swinging in drives with synchronous machines by a field current regulation
Authors: Uhlir I. 
Published: July 2010

AbstractAn electromechanical swinging of a synchronous machine can be damped by a parametric regulation of an exciting current in all cases when a mechanical time constant of a machine is substantially larger than an exciting current constant. The method described is based on the Ljapunov stability theory; it is effective for damping of swinging caused by mains frequency and voltage jitter and by mechanical moment fluctuation. A transfer function choice in an exciting current regulator is demonstrated as well as a real example of a synchronous machine 50 kVA/1500 rpm with a moment of inertia J = 160 kgm2, working as a no‐break stand‐by energy source. A seven times higher damping of swinging due to mains frequency jitter has been reached which initially had attained up to 50 % of nominal power. The description of the machine can be found in [1] and [2].
An analytical method for predicting current harmonics produced by an ac/dc converter under unbalanced supply voltage
Authors: Wang Y. J. , Pierrat L. , Feuillet R. 
Published: July 2010

AbstractThis paper proposes an analytical method for calculating both characteristic and uncharacteristic harmonic currents produced by a six‐pulse AC/DC converter under unbalanced supply voltage. The method allows the mathematical relationship between the complex unbalance factor (i. e. ratio of negative‐sequence voltage to positive‐sequence voltage) and the resulting harmonic currents (magnitudes and phases) to be found. An approximate harmonic model derived from the analysis is also proposed. Comparisons between the basic analytical model, the approximate model and the digital simulation results are given to validate the analysis.
Method for magnetizing curve identification in vector controlled induction machines
Authors: Levi E. 
Published: July 2010

AbstractIf an adaptive induction machine flux model is to be used for rotor flux space vector estimation in a vector controlled drive, the magnetizing curve of the machine has to be known. A desirable feature of the magnetizing curve identification algorithm is that the procedure should constitute a separate routine which can be executed during commissioning of the drive. An experimental procedure, which utilizes current regulated PWM inverter aimed for continuous operation of a vector controlled induction machine, is developed for this purpose. It relies on indirect vector control technique and makes use of a PC implemented indirect vector controller. Appropriate processing of data, obtained during measurements, enables identification of the magnetizing curve. To illustrate the accuracy of the algorithm, results of identification are verified by an existing method aimed for rotor time constant tuning in indirect vector controller.
Procedure for the optimization of sf6 circuit‐breakers
Authors: Habedank U. , Knobloch H. 
Published: July 2010

AbstractThe paper deals with the dimensioning of SF6 circuit‐breakers based on a computer program and short‐circuit breaking tests. The procedure leads to an optimization of the design of the circuit‐breaker taking into account the parameters gas pressure, contact motion, dimensions of the active parts and short‐circuit breaking current. Thus, the most advantageous breaker design no longer has to be determined only by empirical testing.
Influence of absolute humidity on the electrical breakdown in air
Authors: Schmid J. 
Published: July 2010

AbstractOne of the most important insulating gases in high‐voltage technique, the air, is varying with climatic conditions. The most important parameters are the pressure, temperature and the absolute humidity. The influence of humidity on the discharges is investigated in this report. First, the physical processes on the discharge development are discussed in respect to the influence of water vapour in air. Experimental results of the breakdown voltage with variable absolute humidity are explained with these processes. The experimental investigation was done with a rod‐plane gap of 20 cm to 100 cm distance and with different voltage wave shapes. The different influence of water vapour on different predischarge phenomena can be seen in different dependency of the breakdown voltage on the absolute humidity, for each type of predischarge dominating before breakdown.
An overview of present trends in energy management systems development
Authors: Asal H. P. , Dondi P. H. , Glavitsch H. 
Published: July 2010

AbstractThis paper starts with a brief overview of the situation in the electrical industry, with regards to electrical network configurations and operational Energy Management Systems. A concise description is provided of the network control levels, the transfer from electromechanical control to computer based control, and the types of centre‐centre communication involved. The electrical utilities requirements on new systems are then discussed, not as just another „new functional specification for controlling the process”︁ but from the point of view of second generation requirements on computer systems from a group of users now conversant with the application of computer techniques to their industry. This forms the background for considering the emerging trends in the field and the advantages and problems to be solved.
On the meaning of the park power components in three‐phase systems under non‐sinusoidal conditions
Authors: Ferrero A. , Morando A. P. , Ottoboni R. , Superti‐Furga G. 
Published: July 2010

AbstractThe definition and measurement of the power components in three‐phase systems under non‐sinusoidal conditions is becoming more and more an up‐to‐date problem. Some theories have already been proposed to face this problem, but the proposed solutions are not completely satisfactory, in particular when unsymmetrical, unbalanced systems are concerned. The study of three‐phase systems in terms of the Park transformation seems to be more attractive than other proposed methods. The present paper, after a short review of the properties of the Park transformation, discusses the physical meaning of the power components defined employing it, proposes a measuring equipment for the measurement of the defined power components and shows the results of some experimental work.
A new approach to synchronize a bidirectional DC‐to‐DC converter for contacfless power supplies
Authors: Eßer A. 
Published: July 2010

AbstractAfter a short introduction into the field of contactless energy transmission this paper describes a new method to synchronize a bidirectional DC‐to‐DC converter. For example a contactless inductive transmission of energy for robots is introduced. The employed bidirectional DC‐to‐DC converters are used to feed a rotatable transformer. To allow regenerative braking of the robot drives a bidirectional power flow is necessary. Therefore the DC‐to‐DC converter, consisting of two full bridge inverters, has to be clocked synchronously. With the new method only one transformer is needed for bidirectional power flow without any auxiliary components for signal transmission.
Low‐order network equivalents for electromagnetic transients studies
Authors: Kizilcay M. 
Published: July 2010

AbstractNetwork equivalents can be used to represent parts of a power system to reduce the complexity and the computation time during the simulation of electromagnetic transients. The goal is to simplify the representation while preserving the accuracy of transients in the remainder. First, equations for the subnetwork of interest are stated in the frequency domain using network admittance functions. For cases of practical interest, it is shown that these can be approximated by low‐order rational functions using an existing, proven optimization technique of control system engineering. Finally, the Electromagnetic Transients Program (EMTP) has been modified to permit the direct representation of such equivalents, which can be efficiently used for switching surge and fault studies. A detailed numerical example illustrates accuracy and efficiency of the new procedure.
Novel boost quasi‐resonant converter for high‐power applications
Authors: Gao Y. 
Published: July 2010

AbstractIn this paper a novel boost quasi‐resonant converter (boost QRC)for high‐power applications is presented. By using two switches in the boost QRC, the voltage and current stresses of the switches are reduced and the resonant inductor is smaller than in a simple boost resonant converter. There are altogether six operation modes of this boost QRC which are described in this paper. The voltage stress of the switches of this converter is only limited by the output voltage. Therefore the new boost QRC is favourable for high‐voltage and high‐power application. For applications with voltage obtained after rectification of 230 VAC mains a boost QRC was applied with IGBT as switches. Experimental results are presented.