Search results for: Power Transfer Applications.

Authors: Khamael M. Abualnaja, Lidija Šiller, Benjamin R. Horrocks

Abstract:

Alkylated silicon nanocrystals (C11-SiNCs) were prepared successfully by galvanostatic etching of p-Si(100) wafers followed by a thermal hydrosilation reaction of 1-undecene in refluxing toluene in order to extract C11-SiNCs from porous silicon. Erbium trichloride was added to alkylated SiNCs using a simple mixing chemical route. To the best of our knowledge, this is the first investigation on mixing SiNCs with erbium ions (III) by this chemical method. The chemical characterization of C11-SiNCs and their mixtures with Er3+(Er/C11-SiNCs) were carried out using X-ray photoemission spectroscopy (XPS). The optical properties of C11- SiNCs and their mixtures with Er3+ were investigated using Raman spectroscopy and photoluminescence (PL). The erbium mixed alkylated SiNCs shows an orange PL emission peak at around 595 nm that originates from radiative recombination of Si. Er/C11-SiNCs mixture also exhibits a weak PL emission peak at 1536 nm that originates from the intra-4f transition in erbium ions (Er3+). The PL peak of Si in Er/C11-SiNCs mixture is increased in the intensity up to three times as compared to pure C11-SiNCs. The collected data suggest that this chemical mixing route leads instead to a transfer of energy from erbium ions to alkylated SiNCs.

Keywords: Photoluminescence, Silicon Nanocrystals, Erbium, Raman Spectroscopy.

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Authors: J. Ramírez A., A. Rubiano F.

Abstract:

In this paper the direct kinematic model of a multiple applications three degrees of freedom industrial manipulator, was developed using the homogeneous transformation matrices and the Denavit - Hartenberg parameters, likewise the inverse kinematic model was developed using the same method, verifying that in the workload border the inverse kinematic presents considerable errors, therefore a genetic algorithm was implemented to optimize the model improving greatly the efficiency of the model.

Keywords: Direct Kinematic, Genetic Algorithm, InverseKinematic, Optimization, Robot Manipulator

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Authors: Jamuna Bhandari

Abstract:

String matching also known as pattern matching is one of primary concept for network security. In this area the effectiveness and efficiency of string matching algorithms is important for applications in network security such as network intrusion detection, virus detection, signature matching and web content filtering system. This paper presents brief review on some of string matching techniques used for network security.

Keywords: Filtering, honeypot, network telescope, pattern, string, signature.

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Authors: Lidia N. Hernández-Piña, Carlos R. Jaimez-González

Abstract:

Interoperability in distributed systems is an important feature that refers to the communication of two applications written in different programming languages. This paper presents a serializer and a de-serializer of PHP objects to and from XML, which is an independent library written in the PHP programming language. The XML generated by this serializer is independent of the programming language, and can be used by other existing Web Objects in XML (WOX) serializers and de-serializers, which allow interoperability with other object-oriented programming languages.

Keywords: Interoperability, PHP object serialization, PHP to XML, web objects in XML, WOX.

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Authors: Radosveta Sokullu, Engin Karatepe

Abstract:

In the last couple of years Bluetooth has gained a large share in the market of home and personal appliances. It is now a well established technology a short range supplement to the wireless world of 802.11. The two main trends of research that have sprung from these developments are directed towards the coexistence and performance issues of Bluetooth and 802.11 as well as the co-existence in the very short range of multiple Bluetooth devices. Our work aims at thoroughly investigating different aspects of co-channel interference and effects of transmission power, distance and 802.11 interference on Bluetooth connections.

Keywords: Bluetooth, co-channel interference, 802.11, performance analysis

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Authors: A. Zahra, G. de Cesare, D. Caputo, A. Nascetti

Abstract:

PDMS (Polydimethylsiloxane) polymer is a suitable material for biological and MEMS (Microelectromechanical systems) designers, because of its biocompatibility, transparency and high resistance under plasma treatment. PDMS round channel is always been of great interest due to its ability to confine the liquid with membrane type micro valves. In this paper we are presenting a very simple way to form round shapemicrofluidic channel, which is based on reflow of positive photoresist AZ® 40 XT. With this method, it is possible to obtain channel of different height simply by varying the spin coating parameters of photoresist.

Keywords: Lab-on-Chip, PDMS, Reflow, Round microfluidic channel.

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Authors: Alibek Issakhov

Abstract:

In this paper developed and realized absolutely new algorithm for solving three-dimensional Poisson equation. This equation used in research of turbulent mixing, computational fluid dynamics, atmospheric front, and ocean flows and so on. Moreover in the view of rising productivity of difficult calculation there was applied the most up-to-date and the most effective parallel programming technology - MPI in combination with OpenMP direction, that allows to realize problems with very large data content. Resulted products can be used in solving of important applications and fundamental problems in mathematics and physics.

Keywords: MPI, OpenMP, three dimensional Poisson equation

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Authors: N. Ben Si Ali, N. Benalia, N. Zarzouri

Abstract:

Speed sensorless systems are intensively studied during recent years; this is mainly due to their economical benefit and fragility of mechanical sensors and also the difficulty of installing this type of sensor in many applications. These systems suffer from instability problems and sensitivity to parameter mismatch at low speed operation. In this paper an analysis of adaptive observer stability with stator resistance estimation is given.

Keywords: Motor drive, sensorless control, adaptive observer, stator resistance estimation.

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Authors: Andreas Litke, Kostas Zotos, Alexander Chatzigeorgiou, George Stephanides

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The importance of low power consumption is widely acknowledged due to the increasing use of portable devices, which require minimizing the consumption of energy. Energy dissipation is heavily dependent on the software used in the system. Applying design patterns in object-oriented designs is a common practice nowadays. In this paper we analyze six design patterns and explore the effect of them on energy consumption and performance.

Keywords: Design Patterns, Embedded Systems, Energy Consumption, Performance Evaluation, Software Design and Development, Software Engineering.

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Authors: Ravichandra R., Srithar Rajoo, Tan Lit Wen

Abstract:

In recent years Li-Ion batteries getting more attention among the Electrical Vehicles (EV) and Hybrid Electrical Vehicles (HEV) energy storage. Li-Ion has shown extended power density and light weight compared to other batteries readily available in the market. One of the major drawbacks in Li-Ion batteries is their sensitivity to the temperature. If the working temperature is beyond the limit, that could affect seriously on the durability and performance of Li-Ion battery. Thus Battery Thermal Management (BTM) is the most essential in adapting Li-Ion battery to the EVs and HEVs.

Keywords: Li-Ion battery, HEV/EV, battery thermal management, heat generation rate.

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Authors: Anne Sorebo, Oystein Sorebo

Abstract:

The present study was designed to test the influence of intrinsic ICT-motivation, perceived usefulness and ease of use on business students- willingness to use a particular software package. A questionnaire was completed by 196 business students in Norway. We found that 34% of the variance in the students- willingness to use the software could be explained by the three proposed antecedents. Intrinsic ICT-motivation seems to be the most important predictor of students- satisfaction willingness to use the software package.

Keywords: Spreadsheet, business students, technology acceptance, intrinsic motivation.

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Authors: Khan Farhan Rafat, Riaz Ahmed

Abstract:

Renowned offshore organizations are drifting towards collaborative exertion to win and implement international projects for business gains. However, devoid of financial constraints, with the availability of skilled professionals, and despite improved project management practices through state-of-the-art tools and techniques, project delays have become a norm these days. This situation calls for exploring the factor(s) affecting the bonding between project management performance and project success. In the context of the well-known 3M’s of project management (that is, manpower, machinery, and materials), machinery and materials are dependent upon manpower. Because the body of knowledge inveterate on the influence of national culture on men, hence, the realization of the impact on the link between project management performance and project success need to be investigated in detail to arrive at the possible cause(s) of project delays. This research initiative was, therefore, undertaken to fill the research gap. The unit of analysis for the proposed research excretion was the individuals who had worked on skyscraper construction projects. In reverent studies, project management is best described using construction examples. It is due to this reason that the project oriented city of Dubai was chosen to reconnoiter on causes of project delays. A structured questionnaire survey was disseminated online with the courtesy of the Project Management Institute local chapter to carry out the cross-sectional study. The Construction Industry Institute, Austin, of the United States of America along with 23 high-rise builders in Dubai were also contacted by email requesting for their contribution to the study and providing them with the online link to the survey questionnaire. The reliability of the instrument was warranted using Cronbach’s alpha coefficient of 0.70. The appropriateness of sampling adequacy and homogeneity in variance was ensured by keeping Kaiser–Meyer–Olkin (KMO) and Bartlett’s test of sphericity in the range ≥ 0.60 and < 0.05, respectively. Factor analysis was used to verify construct validity. During exploratory factor analysis, all items were loaded using a threshold of 0.4. Four hundred and seventeen respondents, including members from top management, project managers, and project staff, contributed to the study. The link between project management performance and project success was significant at 0.01 level (2-tailed), and 0.05 level (2-tailed) for Pearson’s correlation. Before initiating the moderator analysis test for linearity, multicollinearity, outliers, leverage points and influential cases, test for homoscedasticity and normality were carried out which are prerequisites for conducting moderator review. The moderator analysis, using a macro named PROCESS, was performed to verify the hypothesis that national culture has an influence on the said link. The empirical findings, when compared with Hofstede's results, showed high power distance as the cause of construction project delays in Dubai. The research outcome calls for the project sponsors and top management to reshape their project management strategy and allow for low power distance between management and project personnel for timely completion of projects.

Keywords: Causes of construction project delays, construction industry, construction management, power distance.

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Authors: Roland Lang, Dietmar Bruckner, Rosemarie Velik, Tobias Deutsch

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Modern building automation needs to deal with very different types of demands, depending on the use of a building and the persons acting in it. To meet the requirements of situation awareness in modern building automation, scenario recognition becomes more and more important in order to detect sequences of events and to react to them properly. We present two concepts of scenario recognition and their implementation, one based on predefined templates and the other applying an unsupervised learning algorithm using statistical methods. Implemented applications will be described and their advantages and disadvantages will be outlined.

Keywords: Building automation, ubiquitous computing, scenariorecognition, surveillance system.

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Authors: Yukiko Sasaki Alam, Shahid Alam

Abstract:

Syntactic parsing is vital for semantic treatment by many applications related to natural language processing (NLP), because form and content coincide in many cases. However, it has not yet reached the levels of reliable performance. By manually examining and analyzing individual machine translation output errors that involve syntax as well as semantics, this study attempts to discover what is required for improving syntactic and semantic parsing.

Keywords: Machine translation, error analysis, syntactic errors, knowledge required for parsing.

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Authors: Pierre Abou-Haila, Richard Hall, Mark Dawes

Abstract:

Instead of representing individual cognition only, population cognition is represented using artificial neural networks whilst maintaining individuality. This population network trains continuously, simulating adaptation. An implementation of two coexisting populations is compared to the Lotka-Volterra model of predator-prey interaction. Applications include multi-agent systems such as artificial life or computer games.

Keywords: Collective unconsciousness, neural networks, adaptation, predator-prey simulation.

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Authors: M. F. R. Zuthi, H. H. Ngo, W. S. Guo, S. S. Chen, N. C. Nguyen, L. J. Deng, T. D. C. Tran

Abstract:

Sustaining a desired rate of oxygen transfer for microbial activity is a matter of major concern for biological wastewater treatment (MBR). The study reported in the paper was aimed at assessing the effects of microbial products on the specific oxygen uptake rate (SOUR) in a conventional membrane bioreactor (CMBR) and that in a sponge submerged MBR (SSMBR). The production and progressive accumulation of soluble microbial products (SMP) and bound-extracellular polymeric substances (bEPS) were affecting the SOUR of the microorganisms which varied at different stages of operation of the MBR systems depending on the variable concentrations of the SMP/bEPS. The effect of bEPS on the SOUR was stronger in the SSMBR compared to that of the SMP, while relative high concentrations of SMP had adverse effects on the SOUR of the CMBR system. Of the different mathematical correlations analyzed in the study, logarithmic mathematical correlations could be established between SOUR and bEPS in SSMBR, and similar correlations could also be found between SOUR and SMP concentrations in the CMBR.

Keywords: Microbial products, Microbial activity, Specific oxygen uptake rate, Membrane bioreactor.

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Authors: G.Hariharan, K.Kannan

Abstract:

In this paper, we develop an accurate and efficient Haar wavelet method for well-known FitzHugh-Nagumo equation. The proposed scheme can be used to a wide class of nonlinear reaction-diffusion equations. The power of this manageable method is confirmed. Moreover the use of Haar wavelets is found to be accurate, simple, fast, flexible, convenient, small computation costs and computationally attractive.

Keywords: FitzHugh-Nagumo equation, Haar wavelet method, adomain decomposition method, computationally attractive.

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Authors: Nouri Sabrina, Benzeghiba Mohamed, Ghezal Abderrahmane

Abstract:

Numerical parametric study is conducted to study the effects of ampoule rotation on the flows and the dopant segregation in vertical bridgman (vb) crystal growth. Calculations were performed in unsteady state. The extended darcy model, which includes the time derivative and coriolis terms, has been employed in the momentum equation. It’s found that the convection, and dopant segregation can be affected significantly by ampoule rotation, and the effect is similar to that by an axial magnetic field. Ampoule rotation decreases the intensity of convection and stretches the flow cell axially. When the convection is weak, the flow can be suppressed almost completely by moderate ampoule rotation and the dopant segregation becomes diffusion-controlled. For stronger convection, the elongated flow cell by ampoule rotation may bring dopant mixing into the bulk melt reducing axial segregation at the early stage of the growth. However, if the cellular flow cannot be suppressed completely, ampoule rotation may induce larger radial segregation due to poor mixing.

Keywords: Numerical Simulation, Heat and mass transfer, vertical solidification, chemical segregation.

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Authors: Kongsheng Zhang, Li Ge

Abstract:

It is a one-sided hypothesis testing process for assessing bioequivalence. Bootstrap and modified large-sample(MLS) methods are considered to study individual bioequivalence(IBE), type I error and power of hypothesis tests are simulated and compared with FDA(2001). The results show that modified large-sample method is equivalent to the method of FDA(2001) .

Keywords: Individual bioequivalence, bootstrap, Bayesian bootstrap, modified large-sample.

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Authors: L. Mirtskhulava, M. Khunjgurua, N. Lomineishvili, K. Bakuria

Abstract:

Software reliability prediction gives a great opportunity to measure the software failure rate at any point throughout system test. A software reliability prediction model provides with the technique for improving reliability. Software reliability is very important factor for estimating overall system reliability, which depends on the individual component reliabilities. It differs from hardware reliability in that it reflects the design perfection. Main reason of software reliability problems is high complexity of software. Various approaches can be used to improve the reliability of software. We focus on software reliability model in this article, assuming that there is a time redundancy, the value of which (the number of repeated transmission of basic blocks) can be an optimization parameter. We consider given mathematical model in the assumption that in the system may occur not only irreversible failures, but also a failure that can be taken as self-repairing failures that significantly affect the reliability and accuracy of information transfer. Main task of the given paper is to find a time distribution function (DF) of instructions sequence transmission, which consists of random number of basic blocks. We consider the system software unreliable; the time between adjacent failures has exponential distribution.

Keywords: Exponential distribution, conditional mean time to failure, distribution function, mathematical model, software reliability.

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Authors: M. Yousaf, S. Usman

Abstract:

Numerical studies were conducted using Lattice Boltzmann Method (LBM) to study the natural convection in a square cavity in the presence of roughness. An algorithm based on a single relaxation time Bhatnagar-Gross-Krook (BGK) model of Lattice Boltzmann Method (LBM) was developed. Roughness was introduced on both the hot and cold walls in the form of sinusoidal roughness elements. The study was conducted for a Newtonian fluid of Prandtl number (Pr) 1.0. The range of Ra number was explored from 10^3 to 10^6 in a laminar region. Thermal and hydrodynamic behavior of fluid was analyzed using a differentially heated square cavity with roughness elements present on both the hot and cold wall. Neumann boundary conditions were introduced on horizontal walls with vertical walls as isothermal. The roughness elements were at the same boundary condition as corresponding walls. Computational algorithm was validated against previous benchmark studies performed with different numerical methods, and a good agreement was found to exist. Results indicate that the maximum reduction in the average heat transfer was 16.66 percent at Ra number 10^5.

Keywords: Lattice Boltzmann Method Natural convection, Nusselt Number Rayleigh number, Roughness.

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Authors: R. Sekula

Abstract:

Epoxy composites are broadly used as an electrical insulation for the high voltage applications since only such materials can fulfill particular mechanical, thermal, and dielectric requirements. However, properties of the final product are strongly dependent on proper manufacturing process with minimized material failures, as too large shrinkage, voids and cracks. Therefore, application of proper materials (epoxy, hardener, and filler) and process parameters (mold temperature, filling time, filling velocity, initial temperature of internal parts, gelation time), as well as design and geometric parameters are essential features for final quality of the produced components. In this paper, an approach for three-dimensional modeling of all molding stages, namely filling, curing and post-curing is presented. The reactive molding simulation tool is based on a commercial CFD package, and include dedicated models describing viscosity and reaction kinetics that have been successfully implemented to simulate the reactive nature of the system with exothermic effect. Also a dedicated simulation procedure for stress and shrinkage calculations, as well as simulation results are presented in the paper. Second part of the paper is dedicated to recent developments on formulations of functional composites for electrical insulation applications, focusing on thermally conductive materials. Concepts based on filler modifications for epoxy electrical composites have been presented, including the results of the obtained properties. Finally, having in mind tough environmental regulations, in addition to current process and design aspects, an approach for product re-design has been presented focusing on replacement of epoxy material with the thermoplastic one. Such “design-for-recycling” method is one of new directions associated with development of new material and processing concepts of electrical products and brings a lot of additional research challenges. For that, one of the successful products has been presented to illustrate the presented methodology.

Keywords: Curing, epoxy insulation, numerical simulations, recycling.

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Authors: Camila da Silva, Simone Belorte de Andrade, Vitor Augusto dos Santos Garcia, Vladimir Ferreira Cabral, J. Vladimir Oliveira Lúcio Cardozo-Filho

Abstract:

In the present study, the non-catalytic transesterification of soybean oil in continuous mode using supercritical ethanol were investigated. Experiments were performed in a packed-bed tubular reactor (PBTR) and variable studied were reaction temperature (523 K to 598 K), pressure (10 MPa to 20 MPa), oil to ethanol molar ratio (1:10 to 1:40) and water concentration (0 wt% to 10 wt% in ethanol). Results showed that ethyl esters yields obtained in the PBTR were higher (> 20 wt%) than those verified in a tubular reactor (TR), due to improved mass transfer conditions attained in the PBTR. Results demonstrated that temperature, pressure, oil to ethanol molar ratio and water concentration had a positive effect on fatty acid ethyl esters (FAEE) production in the experimental range investigated, with appreciable reaction yields (90 wt%) achieved at 598 K, 20 MPa, oil to ethanol molar ratio of 1:40 and 10 wt% of water concentration.

Keywords: Packed bed reactor, ethyl esters, continuous process, catalyst-free process.

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Authors: A. Rayati Shavazi, M. Abzari, A. Mohammadzadeh

Abstract:

ICT and supply chain management (SCM) are two notions, which have attracted much attention among both academicians and practitioners during the last decade. However, the discussion of the relationship between the two notions has been limited and fragmented. In this paper, we will present a summary of the discussion of ICT components and SCM on an extensive literature review. Then, we will discuss the interrelation between ICT and SCM from some major components and applications of ICT perspective. After all, we can introduce e-SCM concept, that arisen recently in management literature, in order to cover the whole topic. The authors look at all of the major components of electronic supply chain management and demonstrate that the future holds tremendous opportunity for those firms that take advantage of all of its possibilities.

Keywords: e-SCM3, ICT, IT4, SCM.

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Authors: Touahria Mohamed, Khababa Abdallah, Frécon Louis

Abstract:

This paper proposes a declarative language for knowledge representation (Ibn Rochd), and its environment of exploitation (DeGSE). This DeGSE system was designed and developed to facilitate Ibn Rochd writing applications. The system was tested on several knowledge bases by ascending complexity, culminating in a system for recognition of a plant or a tree, and advisors to purchase a car, for pedagogical and academic guidance, or for bank savings and credit. Finally, the limits of the language and research perspectives are stated.

Keywords: Knowledge representation, declarative language, IbnRochd, DeGSE, facets, cognitive approach.

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Authors: Adil Al-Rammahi

Abstract:

Laplace transformations have wide applications in engineering and sciences. All previous studies of modified Laplace transformations depend on differential equation with initial conditions. The purpose of our paper is to solve the linear differential equations (not initial value problem) and then find the general solution (not particular) via the Laplace transformations without needed any initial condition. The study involves both types of differential equations, ordinary and partial.

Keywords: Differential Equations, Laplace Transformations.

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Authors: Mohamed Eldessouki, Ebraheem Shady, Yasser Gowayed

Abstract:

Carbon nanotubes (CNTs) are known for having high elastic properties with high surface area that promote them as good candidates for reinforcing polymeric matrices. In composite materials, CNTs lack chemical bonding with the surrounding matrix which decreases the possibility of better stress transfer between the components. In this work, a chemical treatment for activating the surface of the multi-wall carbon nanotubes (MWCNT) was applied and the effect of this functionalization on the elastic properties of the epoxy nanocomposites was studied. Functional amino-groups were added to the surface of the CNTs and it was evaluated to be about 34% of the total weight of the CNTs. Elastic modulus was found to increase by about 40% of the neat epoxy resin at CNTs’ weight fraction of 0.5%. The elastic modulus was found to decrease after reaching a certain concentration of CNTs which was found to be 1% wt. The scanning electron microscopic pictures showed the effect of the CNTs on the crack propagation through the sample by forming stress concentrated spots at the nanocomposite samples.

Keywords: Carbon nanotubes functionalization, crack propagation, elastic modulus, epoxy nanocomposites.

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Authors: N. Sanmanee, K. Panishkan, K. Obsuwan, S. Dharmvanij

Abstract:

The increments of aromatic structures are widely used to monitor the degree of humification. Compost derived from mix manures mixed with agricultural wastes was studied. The compost collected at day 0, 7, 14, 21, 28, 35, 49, 77, 91, 105, and 119 was divided into 3 stages, initial stage at day 0, thermophilic stage during day 1-48, and mature stage during day 49-119. The change of highest absorptions at wavelength range between 210-235 nm during day 0- 49 implied that small molecules such as nitrates and carboxylic occurred faster than the aromatic molecules that were found at wavelength around 280 nm. The ratio of electron-transfer band at wavelength 253 nm by the benzonoid band at wavelength 230 nm (E253/E230) also gradually increased during the fermenting period indicating the presence of O-containing functional groups. This was in agreement with the shift change from aliphatic to aromatic structures as shown by the relationship with C/N and H/C ratios (r = - 0.631 and -0.717, p< 0.05) since both were decreasing. Although the amounts of humic acid (HA) were not different much during the humification process, the UV spectral deconvolution showed better qualitative characteristics to help in determining the compost quality. From this study, the compost should be used at day 49 and should not be kept longer than 3 months otherwise the quality of HA would decline regardless of the amounts of HA that might be rising. This implied that other processes, such as mineralization had an influence on the humification process changing HA-s structure and its qualities.

Keywords: Compost maturity, UV spectroscopy, humification, humic acid

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Authors: Syed Sohail Abbas, Sergei Popov

Abstract:

In this paper, a fibre laser at 546 nm has been studied for a signal power of -30 dB. Er3+-doped ZBLAN fibre has been used by upconversion pumping of a 980 nm laser diode. Gain saturation effect has been investigated in detail. Laser performance has also been discussed. An efficiency of 35% has been calculated with a length of 5 mm fibre laser. Results show that Er3+-doped ZBLAN is a promising candidate for optical amplification at 546 nm.

Keywords: Compact visible lasers, Erbium doped, Gainsaturation, Green laser, Optical fibre lasers

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Authors: K. Jabeur, L. D. Buda-Prejbeanu, G. Prenat, G. Di Pendina

Abstract:

MRAM technology provides a combination of fast access time, non-volatility, data retention and endurance. While a growing interest is given to two-terminal Magnetic Tunnel Junctions (MTJ) based on Spin-Transfer Torque (STT) switching as the potential candidate for a universal memory, its reliability is dramatically decreased because of the common writing/reading path. Three-terminal MTJ based on Spin-Orbit Torque (SOT) approach revitalizes the hope of an ideal MRAM. It can overcome the reliability barrier encountered in current two-terminal MTJs by separating the reading and the writing path. In this paper, we study two possible writing schemes for the SOT-MTJ device based on recently fabricated samples. While the first is based on precessional switching, the second requires the presence of permanent magnetic field. Based on an accurate Verilog-A model, we simulate the two writing techniques and we highlight advantages and drawbacks of each one. Using the second technique, pioneering logic circuits based on the three-terminal architecture of the SOT-MTJ described in this work are under development with preliminary attractive results.

Keywords: Spin orbit Torque, Magnetic Tunnel Junction, MRAM, Spintronic, Circuit simulation.

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