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1.
A new construction for the rotor windings of balanced wound-rotor induction motors employed in the slip energy recovery drives is proposed, in this paper, to reduce the time harmonics which are commonly generated in the machine. The proposed machine has a double-circuit in the rotor. One circuit is star connected while the other is delta connected. Each of these two circuits is connected to a diode-bridge rectifier to achieve a twelve-pulse operation characteristics. The main objective of this paper is to develop a new model which is capable of simulating the proposed machine, neglecting nonlinearities due to magnetic saturation, and its associated converters. Such a model is further complicated due to the presence of the two rotor circuits and their mutual interaction 相似文献
2.
Zakaria Chajar Michel Primet Hélène Praliaud Michèle Chevrier Catherine Gauthier Frédéric Mathis 《Catalysis Letters》1994,28(1):33-40
The role of nitrogen dioxide in the selective reduction of NO by propane over a Cu-MFI zeolite is investigated. NO2 and NO reductions were carried out under similar conditions of reaction. In the presence of oxygen, the reduction of NO by C3H8 does not differ significantly from that of NO2. In the absence of oxygen, the reduction of NO2 by propane occurs with a partial decomposition of the nitric dioxide molecule. Such a decomposition leads to the formation of oxygen, which is responsible for the increase in catalytic activity by comparison with the same reaction performed with NO. NO2 formed and released in the gas phase during the reduction of NO by propane in the presence of oxygen does not play a predominant role in the catalytic process. 相似文献
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4.
Privacy issues are frequently discussed amongst researchers, practitioners and patients in healthcare. However, psychiatric patients’ privacy issues get less attention in information system development (ISD), whereby they are one of the most important stakeholders. This paper applies Carew and Stapleton’s ISD privacy framework to psychiatric monitoring systems to understand the issues that are related to monitoring psychiatric patients’ behaviour. By understanding the privacy issues amongst patients, the research will be able to provide guidance to system developers to produce a privacy-sensitive system that can contribute to the system engineering for international stability. We will elaborate each factor in the framework (physical, social, psychological and informational) and then explain the relationship to the privacy of psychiatric patient. 相似文献
5.
Norhayati Zakaria Andrea Amelinckx David Wilemon 《Creativity & Innovation Management》2004,13(1):15-29
A new impetus for greater knowledge‐sharing among team members needs to be emphasized due to the emergence of a significant new form of working known as ‘global virtual teams’. As information and communication technologies permeate every aspect of organizational life and impact the way teams communicate, work and structure relationships, global virtual teams require innovative communication and learning capabilities for different team members to effectively work together across cultural, organizational and geographical boundaries. Whereas information technology‐facilitated communication processes rely on technologically advanced systems to succeed, the ability to create a knowledge‐sharing culture within a global virtual team rests on the existence (and maintenance) of intra‐team respect, mutual trust, reciprocity and positive individual and group relationships. Thus, some of the inherent questions we address in our paper are: (1) what are the cross‐cultural challenges faced by global virtual teams?; (2) how do organizations develop a knowledge sharing culture to promote effective organizational learning among culturally‐diverse team members? and; (3) what are some of the practices that can help maximize the performance of global virtual teams? We conclude by examining ways that global virtual teams can be more effectively managed in order to reach their potential in this new interconnected world and put forward suggestions for further research. 相似文献
6.
Guillermo A. Oliveira Udry Laura Tiessler-Sala Eva Pugliese Agathe Urvoas Zakaria Halime Jean-Didier Marchal Jean-Pierre Mahy Rmy Ricoux 《International journal of molecular sciences》2022,23(23)
The covalent insertion of a cobalt heme into the cavity of an artificial protein named alpha Rep (αRep) leads to an artificial cobalt hemoprotein that is active as a catalyst not only for the photo-induced production of H2, but also for the reduction of CO2 in a neutral aqueous solution. This new artificial metalloenzyme has been purified and characterized by Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS), circular dichroism, and UltraViolet–Visible spectroscopy. Using theoretical experiments, the structure of this biohybrid and the positioning of the residues near the metal complex were examined, which made it possible to complete the coordination of the cobalt ion by an axial glutamine Gln283 ligand. While the Co(III)–porphyrin catalyst alone showed weak catalytic activity for both reactions, 10 times more H2 and four times more CO2 were produced when the Co(III)–porphyrin complex was buried in the hydrophobic cavity of the protein. This study thus provides a solid basis for further improvement of these biohybrids using well-designed modifications of the second and outer coordination sphere by site-directed mutagenesis of the host protein. 相似文献
7.
Nornikman Hassan Zahriladha Zakaria Weng Yik Sam Izyan Nazihan Mohd Hanapiah A. Nasoruddin Mohamad Ameer Farhan Roslan Badrul Hisham Ahmad Mohd Khairy Ismail Mohamad Zoinol Abidin Abd Aziz 《国际射频与微波计算机辅助工程杂志》2019,29(1)
This work focusing on the dual‐band antenna design with rectifying circuit for energy transfer system technology for enhancement gain performance. The air gap technique is applied on this microstrip antenna design work to enhance the antenna gain. The work begins with designing and analyzing the antenna via the CST Microwave Studio software. After validation on acceptable performance in simulation side is obtained, the return loss, S11 of the antenna is measured using vector network analyzer equipment. The rectifier circuit is used to convert the captured signal to DC voltage. This projected dual‐band antenna has successfully accomplished the target on return loss of ?44.707 dB and ?32.163 dB at dual resonant frequencies for 1.8 GHz and 2.4 GHz, respectively. This proposed antenna design benefits in low cost fabrication and has achieved high gain of 6.31 dBi and 7.82 dBi for dual‐band functioning frequencies. 相似文献
8.
9.
Zakaria Farah 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1979,168(5):394-396
Summary Non-casein protein fractions of raw skim med milk, obtained according to the Aschaffenburg and Drewry procedure, were studied by discontinuous polyacrylamide electrophoresis.Differences between the electropherograms obtained and the data of the above authors were observed in the fractions non-casein nitrogen minus proteose peptone nitrogen and total albumin nitrogen plus non-protein nitrogen.In the first fraction, instead of immunoglobulin, proteose-peptone was present and in the second fraction, besides the total albumin, immunglobulin and proteose-peptone were present. In our opinion the differences observed in the two fractions are due to incomplete salting out.
Überprüfung der Aschaffenburg und Drewry-Bestimmungsmethode der Nicht-Casein-Proteine durch Polyacrylamid-Elektrophorese
Zusammenfassung Es wurden Nicht-Casein-Protein-Fraktionen von roher Magermilch, die nach der Aschaffenburg- und Drewry-Methode getrennt wurden, discelektrophoretisch untersucht. Unterschiede zwischen den erhaltenen Elektropherogrammen und den Angaben der oben genannten Autoren wurden bei den Fraktionen Nicht-Casein-Stickstoff minus Proteose-Pepton-Stickstoff und Totalalbumin-Stickstoff plus Nicht-Protein-Stickstoff festgestellt.Bei der ersten Fraktion wurde das Proteose-Pepton anstatt Immunglobulin erhalten, und bei der zweiten Fraktion erhielt man neben dem Totalalbumin auch Immunglobulin und Proteose-Pepton. Nach unserer Auffassung sind die bei den beiden Fraktionen festgestellten Abweichungen auf unvollständiges Aussalzen zurückzuführen.相似文献
10.
Mohd Ikram Ramli Abu Bakar Sulong Norhamidi Muhamad Andanastuti Muchtar Mohd Yusuf Zakaria 《Ceramics International》2019,45(9):11648-11653
Composite biomaterials are in high demand in the medical field of today. The combination of bioactive wollastonite (WA) glass ceramic with the biocompatibility of alloy titanium (Ti6Al4V) could be a good candidate for implant applications. The rheological properties of Ti6Al4V/WA feedstock show a pseudoplastic behaviour with low activation energy. The feedstock was successfully injected as a green part with no defects. The green part was solvent debound for 6?h in heptane and thermal debound in an argon environment for 1?h. The brown part was successfully sintered at 1300?°C for 3?h with 5?°C/min heating and cooling rates. The average sintered density was 4.12?g/cm3; which is 97.5% from the theoretical density. The highest Young's modulus obtained was 18.10?GPa; which is in the range of human bone strength. EDX analysis shows that by increasing sintering temperature, the level of oxygen decreased. Cell viability test shown an absorbance increased with days increasing indicated that the cellular were proliferated on the composite Ti6Al4V/WA composite which also proved that the composite was non-toxic. This indicates that the Ti6Al4V/WA composite is suitable for bone implant applications. 相似文献