Relevant bibliographies by topics / Constant magnet

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Constant magnet'

Author: Grafiati
Published: 30 May 2022
Last updated: 31 May 2022

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Journal articles on the topic "Constant magnet"

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Radovinsky, Alexey L., Leslie Bromberg, Joseph V. Minervini, Philip C. Michael, Thomas Servais, Eric Forton, and Emma Pearson. "Constant Field Toroidal SMES Magnet." IEEE Transactions on Applied Superconductivity 26, no. 3 (April 2016): 1–4. http://dx.doi.org/10.1109/tasc.2015.2509246.

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Pan, Xue Hai. "Constant Voltage Analysis of Permanent Magnet Generator." Applied Mechanics and Materials 63-64 (June 2011): 970–73. http://dx.doi.org/10.4028/www.scientific.net/amm.63-64.970.

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This paper discusses and analysis the constant voltage of vehicle applied permanent magnet generator. The permanent magnet can produce magnetic field in an air gap with no excitation winding and no dissipation of electric power, when the rotor turns, the magnet field turns, the generator generates electricity, with the permanent magnet material of high remnant magnetic induction and the optimized design of the generator, the output voltage is improved when the engine at low speed. We develop a single-phase double half-wave electric regulator is to ensure the stability of the output voltage and can direct output direct current.
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Akinloye, B. O., and G. O. Uzedhe. "Controllable single-phase smart synchronous generator towards solar-pneumatic power generation." Nigerian Journal of Technology 39, no. 2 (July 16, 2020): 493–99. http://dx.doi.org/10.4314/njt.v39i2.19.

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This paper presents the development of a controllable single-phase surface-mounted permanent magnet synchronous generator (SPSMPMSG) for low speed applications. Presently, the world is faced with degrading climatic conditions that may be worsen if energy need is met by fossil fuel and other conventional means of generation. On the other hand, renewable alternatives are not always of constant speed, and are usually not high enough to turn conventional alternators. There is therefore a need for the development of alternators that can generate electricity from low speed sources. The development of permanent magnet from rare-earth materials has revolutionized the electrical generator development. Permanent magnet machines are characterized by high torque, low noise, high efficiency and high power factor. The use of these magnets also made it possible to add computer based controllability making the generator a smart machine. This paper presents a CAD design of smart generator at an input speed of 500rpm to a turbine to produce a constant output of 220V. Simulation and physical test results produce an output of 220V ± 1% and give a clear indication that low speed renewable energy sources can produce usable electrical power. Keywords: Smart generator, Permanent magnet generator, stator, rotor, Computer-aided design.
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Armando, Eric, Sandro Rubino, Aldo Boglietti, Enrico Carpaneto, Salvatore Musumeci, and Daniele Martinello. "A Test Procedure to Evaluate Magnets Thermal Time Constant of Permanent Magnet Machines." IEEE Transactions on Industry Applications 57, no. 5 (September 2021): 4694–706. http://dx.doi.org/10.1109/tia.2021.3090745.

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Heydari, M. B., M. Asgari, L. Gharib, A. Keshtkar, N. Jafari, and M. Zolfaghari. "A Novel Augmented Railgun Using Permanent Magnets." Advanced Electromagnetics 8, no. 1 (June 9, 2019): 99–105. http://dx.doi.org/10.7716/aem.v8i1.961.

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A novel augmented railgun using a permanent magnet is proposed in this paper. The effects of the permanent magnet on the magnetic field and distribution of current density have been investigated. High current densities in the railguns can lead to high local temperature and erosion of the rails. Therefore, the current densities in the rails and armature should be decreased without the reduction of the Lorentz force which is required for acceleration. For this purpose, augmentation of the magnetic field can be used as an effective method. The Finite Element Method (FEM) simulations have been applied in this article to analyze the performance of the railgun in the presence of the magnets. Two augmented railgun structures have been introduced to produce a constant external magnetic field. For both structures, augmented railgun characteristics are studied in comparison to the railgun without the augmentation. The results show that augmentation with permanent magnet increases railgun efficiency, especially in low current railguns. For pulse current source I=30kA, Lorentz force of the augmented railgun with four magnets is 2.02 times greater than the conventional railgun.
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Otsuka, A., and T. Kiyoshi. "High-Field Magnet Design Under Constant Hoop Stress." IEEE Transactions on Applied Superconductivity 18, no. 2 (June 2008): 1529–32. http://dx.doi.org/10.1109/tasc.2008.920531.

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Ma, Zhimin, and Xiaogang Qi. "Permanent magnet motor temperature compensated constant torque control." IFAC-PapersOnLine 51, no. 31 (2018): 68–70. http://dx.doi.org/10.1016/j.ifacol.2018.10.013.

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SUMMERS, D. J. "MUON ACCELERATION USING FIXED FIELD, ALTERNATING GRADIENT (FFAG) RINGS." International Journal of Modern Physics A 20, no. 16 (June 30, 2005): 3861–64. http://dx.doi.org/10.1142/s0217751x05027813.

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Given their 2.2 μs lifetime, muons must be accelerated fairly rapidly for a neutrino factory or muon collider. Muon bunches tend to be large. Progress in fixed field, alternating gradient (FFAG) lattices to meet these challenges are reviewed. FFAG magnets are naturally wide; low momentum muons move from the low field side of a gradient magnet to the high field side as they gain energy. This can be exploited to do double duty and allow a large beam admittance without unduly increasing the magnetic field volume. If the amount of RF must be reduced to optimize cost, an FFAG ring can accommodate extra orbits. I describe scaling FFAGs in which the bends in each magnet are energy independent and non-scaling FFAGs in which the bends in each magnet do vary with muon energy. In all FFAG designs the sum of the bends in groups of magnets are constant; otherwise orbits would not close. Ways of keeping the accelerating beam in phase with the RF are described. Finally, a 1 MeV proof of principle scaling FFAG has been built at KEK and began accelerating protons in June 2000 with a 1 kHz repetition rate.
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Nagaya, K., and N. Arai. "Analysis of a Permanent Magnet Levitation Actuator With Electromagnetic Control." Journal of Dynamic Systems, Measurement, and Control 113, no. 3 (September 1, 1991): 472–78. http://dx.doi.org/10.1115/1.2896434.

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This paper proposes an actuator in the magnetic levitation system using a permanent magnet and an electromagnet. In this system, the gravity force of the masses is supported by a strong permanent magnet in which two identical poles face each other. The vibration due to external disturbances is controlled by use of the electromagnet by changing magnetic fluxes of one of the permanent magnets. The analytical expressions for obtaining the levitation force, spring constant, and the control force versus the electric current in the electromagnet were derived using the equation of the electromagnetic theory. Numerical simulations under the control using the optimal regulator for the magnetically levitated body were carried out. To verify the present theoretical results, experimental results were also obtained.
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Mohammad, Ummu Atiqah Khairiyah B., A. K. M. Nurul Amin, Mohd Redzuan Bin Abdul Rappat, and Muammer D. Arif. "Effect of Application of a Combination of Magnets on Chatter Amplitude Reduction in Turning of Stainless Steel AISI 304." Applied Mechanics and Materials 393 (September 2013): 189–93. http://dx.doi.org/10.4028/www.scientific.net/amm.393.189.

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This paper presents the results of experimental investigations of vibration analysis conducted on Engine Lathe Harrison M390 using variable cutting speed, feed rate and depth of cut at constant tool overhang of 120mm as the machining parameters ascertain the effectiveness of TiN coated carbide insert in turning of hardened steel AISI 304. The experiments were designed based on the Response Surface Methodology (RSM) approach using DESIGN EXPERT (DOE) software to enhance statistical model using the capabilities of RSM to compare the effectiveness of application of a combination of a bottom and a side magnet with respect to the tool holder in terms of reduction of chatter amplitude. The experiments were performed under application of magnetic field from two permanent magnets with magnetic strength of 1200 Gauss each with one located at the bottom and the other at the side of the cutting tool with distance 1cm from the tool. The dimension of the bottom magnet was 25 x 25 x 50mm and that of the side magnet was 87 x 50 x 17mm. The vibration amplitude data for the two conditions were compared to identify the influence of magnet on chatter reduction. The results reveal that a maximum of 87% and an average of 50% reduction of chatter acceleration amplitude were achieved with the said arrangement of the magnets. Furthermore, empirical mathematical model of maximum chatter amplitude was developed for machining with magnet application to predict the cutting parameters with the lowest value of chatter amplitude and maximum material removal rate.
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Dissertations / Theses on the topic "Constant magnet"

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Alsawalhi, Jamal Yousuf. "An asymmetric salient permanent magnet synchronous machine for wide constant power speed range applications." Thesis, Purdue University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3686817.

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This work introduces a novel permanent-magnet synchronous machine (PMSM) architecture that employs rotational asymmetry to increase the torque density output in constant power variable speed applications. A population based multi-objective design optimization algorithm is used to design and analyze the new machine topology. A number of design studies are presented to show that the proposed machine structure outperforms a conventional PMSM machine. Validation of the analytical machine design model using a three dimensional finite element analyses is performed and the results are presented. Finally, a case study in which a hybrid electric bus traction motor is designed is presented.

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De, Kock Hugo Werner. "Dynamic control of the permanent magnet assisted reluctance synchronous machine with constant current angle." Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/2062.

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Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2006.
This thesis is about the dynamic control of a permanent magnet assisted reluctance synchronous machine (PMA RSM). The PMA RSM in this thesis is a 110 kW traction machine and is ideal for the use in electrical rail vehicles. An application of the dynamic control of the PMA RSM in electrical rail vehicles is to reduce wheel slip. The mathematical model of the PMA RSM is derived and explained in physical terms. Two methods of current control for the PMA RSM are investigated, namely constant field current control (CFCC) and constant current angle control (CCAC). It is shown that CCAC is more appropriate for the PMA RSM. A current controller for the PMA RSM that guarantees stability is derived and given as an analytic formula. This current controller can be used for any method of current control, i.e. CFCC or CCAC. An accurate simulation model for the PMA RSM is obtained using results from finite element analysis (FEA). The accurate model is used in a simulation to verify CCAC. A normal proportional integral speed controller for the PMA RSM is designed and the design is also verified by simulation. Practical implementation of the current and speed controllers is considered along with a general description of the entire drive system. The operation of the resolver (for position measurement) is given in detail. Important safety measures and the design of the electronic circuitry to give protection are shown. Practical results concerning current and speed control are then shown. To improve the dynamic performance of the PMA RSM, a load torque observer with compensation current feedback is investigated. Two observer structures are considered, namely the reduced state observer and the full state observer. The derivation of the full state observer and the detail designs of the observer elements are given. The accurate simulation model of the PMA RSM is used to verify the operation of the observer structures and to evaluate the dynamic performance. Both observer structures are implemented practically and practical results are shown. One method of position sensorless control, namely the high frequency voltage injection method, is discussed in terms of the PMA RSM. This work is additional to the thesis but it is shown, because it raises some interesting questions regarding the dynamic control of the PMA RSM.
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Rim, Geun-hie. "Variable speed constant frequency power conversion with permanent magnet synchronous and switched reluctance generators." Diss., Virginia Tech, 1992. http://hdl.handle.net/10919/40015.

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Chin, Yung-Kang. "A permanent magnet synchronous motor for an electric vehicle - design analysis." Licentiate thesis, KTH, Electrical Systems, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-1763.

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This thesis presents the study and the design analysis of apermanent magnet synchronous motor (PMSM) for the tractionapplication of an electric vehicle. An existing inductiontraction motor for an electric forklift benchmarks the expectedperformances of the proposed PMSM design. Further, thepossibility of using the identical stator as the one used inthe induction motor is explored for the fast prototyping. Theprototype motor is expected to be field-weakened and to have aconstant power speed range (CPSR) of 2.5 to 3.

A design approach based on the CPSR contour plot in aninterior permanent magnet (IPM) parameter plane is derived toobtain the possible designs that meet all the designspecifications and the targeted CPSR. This study provides thepossible alternative designs for the subsequent futureprototype motors.

An analytical approach to estimate the iron loss in PMsynchronous machines is developed and included in the designprocedure. The proposed technique is based on predicting theflux density waveforms in the various regions of the machine.The model can be applied at any specified load condition,including the field-weakening operation region. This model canbe ultimately embedded in the design process for a routine usein loss estimations.

The first prototype motor with an inset permanent magnetrotor has been built and the available measurements are used tovalidate the design performance. In particular, the thermalanalyses based both on the lumped-circuit approach and thenumerical method are compared with the measured results. Asecond and possibly a third prototype motor targeting a widerand higher performance will be carried out in the continuingphase of the project.

Keywords:Constant Power Speed Range, Electric Vehicles,Field-weakening, Reference Flux Linkage, Iron Loss, PermanentMagnet Synchronous Motor, Thermal Analysis

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Rim, Geun-hie. "Modeling, analysis and experimental verification of variable-speed constant-frequency power conversion scheme with a permanent magnet synchronous generator." Thesis, This resource online, 1988. http://scholar.lib.vt.edu/theses/available/etd-06062008-163303/.

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Miao, Dongmin. "Voltage Stabilization Control of Wide-Speed-Range Permanent-Magnet Synchronous Generator Systems." Doctoral thesis, Universite Libre de Bruxelles, 2016. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/246410.

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DC power systems have a constant DC-link voltage, as well as the advantages such as high stability, high efficiency, small size and light weight; therefore, they are widely used in stand-alone power systems, e.g. the power systems in aircrafts and automobiles, isolated wind power generation systems, etc. Permanent-Magnet Synchronous Generators (PMSGs) possess the advantages including high power density, high efficiency, and high control precision, and have obtained great attention and have been widely used in military, inductry, and daily life. Pulse Width Modulation (PWM) rectifier has been one of the main power conversion topologies thanks to its full controllability. The key point in the dissertation is to study the DC power system consisting of a PMSG to be the main power input device and a PWM rectifier to be the main power conversion topology. The objective of control is to output a constant DC-link voltage in a wide PMSG speed range. Since the PM-excited flux linkage is constant, when the PMSG is working at a high speed, field-weakening is needed to stabilize the stator voltage, further to stabilize the DC-link voltage. Hybrid excitation may be used to realize the field-weakening, but it has complex structure; no auxiliary devices are needed in the field regulation with the armature current, and can be easily realized with the PWM recifier and field-regulation control strategies. In this dissertation, the typical applications of the DC power systems are first introduced, with a comprehensive analysis and elaboration on the relevant research throughout the world. The research work is focused on the DC power system and its stabilization control, which is composed of a PMSG and a PWM rectifier. The involved research content in this dissertation includes the following aspects: 1. DC power system design with a wide-speed-range PMSGAs for the common DC power systems, PMSG with high power density, high efficiency is selected to the system power input device, usually with a variable-speed prime mover. The PWM rectifier with fully controlled switches is chosen to be the power conversion topology, which converts the AC power generated by PMSG into DC power, and supplies the DC load after the DC filter. The matching between the system requirements and the generator parameters are determined. Through finite-element analysis (FEA), a PMSG with strong field-weakening ability and suitable for wide-speed-range operation has been designed and manufactured, and the system test bench has been built based on dSPACE. 2. Study, analysis, optimization and experimental verification of the traditional control strategiesAccording to the PMSG designed in part 1, the DC-link model has been built, as well as the control model of the traditional control strategies, e.g. field-oriented control (FOC), direct torque control (DTC), and the effectiveness of the DC-link voltage stabilization control has been verified in a wide speed range. The theory of active damping has been proposed and analyzed, and has been utilized in the DC-link voltage control. When the load on the DC-link changes, the dynamic response of the DC-link voltage has been greatly accelerated, and it recovers quickly to its reference value. In the meantime, the performance influence of the prime mover speed on the actual system test bench should be considered. Finally, the performance of FOC and DTC has been compared and analyzed. 3. Analysis and experimental verification of the direct voltage control (DVC), and the comparative study of all the studied control strategiesThe derivation process of DVC has been theoretically analyzed: the inner current loops in FOC have been eliminated to obtain the direct voltage field-oriented control (DVFOC); the reference value of d-axis voltage in DVFOC has been replaced by the product of the stator voltage calculated by the speed and the load condition, and the sine value of load angle generated by the DC-link voltage PI controller, in order to form the DVC-1. Further, the DC-link voltage PI controller directly outputs the reference value of load angle and it becomes DVC-2. Finally, the comparative study has been carried out among all the studied control strategies.
Doctorat en Sciences de l'ingénieur et technologie
info:eu-repo/semantics/nonPublished
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Любарський, Борис Григорович. "Моделювання та розробка комбінованого збудження зварювальних генераторів постійного струму з метою поліпшення їх техніко-економічних показників." Thesis, НТУ "ХПІ", 2001. http://repository.kpi.kharkov.ua/handle/KhPI-Press/5320.

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Дисертація присвячена питанням підвищення ККД зварювальних генераторів постійного струму. З метою підвищення ККД запропонована нова комбінована електромагнітна та магнітоелектрична система збудження зварювального генератора. Розроблена методика розрахунку електромагнітних характеристик генератора за результатами розрахунку магнітного поля методом скінчених елементів. Проведено аналіз впливу торцевих полів розсіювання на адекватність моделі постійного магніту прийнятої при розрахунку магнітного поля. Розроблена математична модель залежності усталеності горіння дуги від довжини повітряного зазору та струму збудження. Створена загальна схема розрахунку зварювального генератора. Розроблено та створено експериментальний зварювальний генератор з комбінованим збудженням та проведено його випробування. Створена модель дослідного зварювального генератора.
The dissertation is devoted by a problem of increase efficiency of welding generators of a direct current. With the purpose of increase efficiency the offered new combined electromagnetic and permanent magnet system of excitation of the welding generator. The design procedure of electromagnetic characteristics of the generator on results of calculation of a magnetic field is created by a method of final elements. The analysis of influence of face fields of dispersion on adequacy of model of a constant magnet accepted is carried spent at calculation of a magnetic field. The mathematical model of dependence of stability of burning of an arch from length of an air backlash and a current of excitation is developed. The general circuit of calculation of the welding generator is created. The experimental welding generator with the combined excitation is developed and created and its tests are carried spent. The created model of the experienced welding generator.
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Santos, Michelly Christine dos. "Nanopartículas magnéticas funcionalizadas com bicamada de ácido láurico: caracterização, associação de moléculas bioativas e estudo de interação com BSA." Universidade Federal de Goiás, 2012. http://repositorio.bc.ufg.br/tede/handle/tede/8867.

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Made available in DSpace on 2018-09-11T11:11:24Z (GMT). No. of bitstreams: 2 Dissertação- Michelly Christine dos Santos - 2012.pdf: 1834625 bytes, checksum: af88a6d02e2b5362de31315d2c4ff78c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2012-10-11
Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
Magnetic nanoparticles with two different chemical compositions, magnetite and zinc doped manganese ferrite were synthesized, functionalized with lauric acid bilayers and dispersed into water yielding stable aqueous colloidal suspensions at physiological pH. Bioactive molecules of different sizes, Amphotericin B and curcumin, were associated to the lauric acid bilayers of the suspended nanoparticles. X-ray diffraction analyses reveled a diffraction pattern characteristic of the cubic spinel crystalline phase for both samples. The nanoparticles average size estimated by Debye-Scherrer’s formula was 9 nm for zinc doped manganese ferrite and 8 nm for magnetite. The hysteresis curves showed that the nanoparticles are super paramagnetic at room temperature with saturation magnetization of 44.2 emug-1 for zinc doped manganese ferrite and 51.5 emug-1 for magnetite. The IR analysis showed the presence of lauric acid associated to the nanoparticles, and the TG curves showed a higher amount of lauric acid bonded to zinc doped manganese ferrite. The hydrodynamic diameters of the nanoparticles indicate that they are dispersed into the suspension as aggregates, and that the association of bioactive molecules did not affect the hydrodynamic sizes of the aggregates. The IR spectra confirmed the presence of bioactive molecules in the formulations and the UV-VIS spectra showed that these molecules are solubilized into the lauric acid bilayers in their monomeric forms. The functionalized nanoparticles containing the bioactive molecules present less negative zeta potential than the lauric acid functionalized nanoparticles, indicating that the bioactive molecules interact with the medium of the suspensions. The evaluation of aggregation of the nanoparticles in cell culture medium showed that the nanoparticles aggregation is significantly reduced by the addition of proteins (FBS and BSA) in cell culture medium. The study of interaction of the nanoparticles with bovine serum albumin before and after the association with the bioactive molecules showed that these systems present great affinity for BSA, with binding constants (Kb) in the range of 105 -106M-1. These results suggest that the nanoparticles functionalized with lauric acid bilayers, pure or associated to amphotericin B and curcumin, can be bioconjugated to proteins producing formulations with higher colloidal stability in biological media.
Nanopartículas magnéticas com duas diferentes composições químicas, magnetita e ferrita de manganês dopada com zinco, foram sintetizadas, funcionalizadas com bicamadas de ácido láurico e dispersas em meio aquoso produzindo suspensões coloidais estáveis em pH fisiológico. Posteriormente, foram associadas moléculas bioativas de tamanhos diferentes, Anfotericina B e curcumina, nas bicamadas de ácido láurico funcionalizadas nos dois tipos de nanopartículas em suspensão. A caracterização estrutural e composicional das nanopartículas foi realizada por difração de raios X e análise química dos teores de íons metálicos. Os difratogramas mostraram um padrão de difração referente à formação de material constituído por uma única fase cristalina cúbica do tipo espinélio. Os tamanhos médios estimados pela fórmula de Debye-Scherrer foram 9 e 8 nm para as nanopartículas de ferrita de manganês dopadas com zinco e de magnetita, respectivamente. Os teores dos íons metálicos indicaram um pequeno desvio na estequiometria final dos sólidos em relação à estequiometria inicial. As técnicas utilizadas para caracterizar as nanopartículas funcionalizadas antes e após a associação da Anfotericina B e da curcumina foram IV, UV-VIS, TG, VSM e ainda foram realizadas medidas de potencial zeta e de diâmetro hidrodinâmico. As curvas de histerese indicaram a formação de nanopartículas superparamagnéticas à temperatura ambiente com magnetização de saturação de 44,2 emug-1 para a ferrita de manganês dopada com zinco e 51,6 emug-1 para a magnetita. As análises de IV mostraram que as nanopartículas foram funcionalizadas com ácido láurico e as curvas de TG indicaram que as nanopartículas de ferrita de manganês dopadas com zinco contêm maior quantidade de ácido láurico do que as nanopartículas de magnetita. Os valores de diâmetros hidrodinâmicos das nanopartículas indicaram que as mesmas estão dispersas na suspensão na forma de agregados e que a associação das moléculas bioativas não influenciou nos tamanhos hidrodinâmicos dos agregados. Os espectros de IV comprovaram a presença das moléculas bioativas nas formulações e a análise dos espectros de UV-VIS mostrou que as moléculas bioativas estão solubilizadas nas bicamadas de ácido láurico em suas formas monoméricas. As nanopartículas funcionalizadas associadas às moléculas bioativas apresentaram potencial zeta menos negativo que as nanopartículas funcionalizadas, indicando que as moléculas bioativas interagem com o meio das suspensões. O estudo de agregação de nanopartículas em meio de cultura celular mostrou que a adição de proteínas contribui significativamente para a diminuição da agregação das nanopartículas neste meio. O estudo de interação entre a albumina de soro bovino (BSA) e as nanopartículas funcionalizadas antes e após a associação das moléculas bioativas mostrou que os sistemas têm grande afinidade com a BSA, com constantes de ligação (Kb) da ordem de 105–106 M-1. Esses resultados sugerem que as nanopartículas funcionalizadas com bicamadas de ácido láurico, puras ou associadas à Anfotericina B e à curcumina podem ser bioconjugadas a essa proteína produzindo formulações com maior estabilidade coloidal em meios biológicos.
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Pennanen, T. (Teemu). "Computational studies of NMR and magneto-optical rotation parameters in water." Doctoral thesis, University of Oulu, 2012. http://urn.fi/urn:isbn:9789514297311.

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Abstract In this thesis nuclear magnetic resonance (NMR) and magneto-optical rotation (MOR) parameters are investigated for water, paying special attention to the effect of solvation from gaseous to liquid phase. Nuclear magnetic shielding and quadrupole coupling tensors of NMR spectroscopy are studied for gaseous and liquid water. Liquid state is modelled by a 32-molecule Car-Parrinello molecular dynamics simulation, followed by property calculations for the central molecules in clusters cut out from the simulation trajectory. Gaseous state is similarly represented by a one-molecule simulation. Gas-to-liquid shifts for shielding constants obtained this way are in good agreement with experiments. To get insight into the local environment and its effect on the properties the clusters are divided into groups of distinct local features, namely the number of hydrogen bonds. The analysis shows in detail how the NMR tensors evolve as the environment changes gradually from the gas to liquid upon increasing the number of hydrogen bonds to the molecule of interest. The study sheds light on the usefulness of NMR experiments in investigating the local coordination of liquid water. To go a bit further, the above mentioned NMR parameters along with the spin-spin coupling constant are examined for water dimer in various geometries to have insight into solvation and hydrogen bonding phenomena from bottom to top. Characteristic changes in the properties are monitored as the geometry of the dimer is systematically varied from very close encounter of the monomers to distances and orientations where hydrogen bonding between monomers ceases to exist. No rapid changes during the hydrogen bond breaking are observed indicating that the hydrogen bonding is a continuous phenomenon rather than an on-off situation. However, for analysis purposes we provide an NMR-based hydrogen bond definition, expressed geometrically, based on the behaviour of the NMR properties as a function of dimer geometry. Our definition closely resembles widely used definitions and thus reinforces their validity. Magneto-optical rotation parameters, the nuclear spin optical rotation (NSOR) and the Verdet constant, are computed for gaseous and liquid water, in the same manner as the NMR properties above. Recent pioneering experiments including NSOR for hydrogen nuclei in liquid water and liquid xenon have demonstrated that this technique has a potential to be a useful new probe of molecular structure. We reproduce computationally, applying a first-principles theory developed recently in the group, the experimental NSOR for hydrogen nuclei in liquid water, and predict hydrogen NSOR in gaseous water along with the oxygen NSOR in liquid and gaseous water. NSOR is an emerging experimental technique that needs interplay between theory and computation for validation, steering and insight.
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Austrin, Lars. "On magnetic amplifiers in aircraft applications." Licentiate thesis, Stockholm : Elektrotekniska system, Kungliga Tekniska högskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4439.

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Books on the topic "Constant magnet"

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1966-, Łaba Izabella, ed. Multiparticle quantum scattering in constant magnetic fields. Providence, RI: American Mathematical Society, 2001.

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Gérard, Christian. Multiparticle quantum scattering in constant magnetic fields. Providence, R.I: American Mathematical Society, 2002.

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Kuan, Wei-Peng. Methods and procedures for localized in vivo 31P magnetic resonance spectroscopy: A new modality of diagnostic radiology. 1989.

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Solymar, L., D. Walsh, and R. R. A. Syms. Artificial materials or metamaterials. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198829942.003.0015.

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The difference between natural and artificial materials is explained. The equivalent plasma frequency of wire media is derived. A list of metamaterial resonators is presented. The possibility of achieving negative refraction and its significance are discussed. It is shown that under certain circumstances it is possible to produce a perfect lens that could transfer evanescent waves aswell. Themulti-layer lens is shown to have advantages over the single-layer lens. The operation of a SiC lens based on the negative dielectric constant due to optical phonons is discussed. Detectors for magnetic resonance imaging, relying on the resonance of magnetoinductive waves are shown to be a potential application.
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Oliver, Jennifer H. Shipwreck in French Renaissance Writing. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198831709.001.0001.

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In the sixteenth century, a period of proliferating transatlantic travel and exploration, and, latterly, religious civil wars in France, the ship is freighted with political and religious, as well as poetic, significance; symbolism that reaches its height when ships – both real and symbolic – are threatened with disaster. The Direful Spectacle argues that, in the French Renaissance, shipwreck functions not only as an emblem or motif within writing, but as a part, or the whole, of a narrative, in which the dynamics of spectatorship and of co-operation are of constant concern. The possibility of ethical distance from shipwreck – imagined through the Lucretian suave mari magno commonplace – is constantly undermined, not least through a sustained focus on the corporeal. This book examines the ways in which the ship and the body are made analogous in Renaissance shipwreck writing; bodies are described and allegorized in nautical terms, and, conversely, ships themselves become animalized and humanized. Secondly, many texts anticipate that the descriptionof shipwreck will have an affect not only on its victims, but on those too of spectators, listeners, and readers. This insistence on the physicality of shipwreck is also reflected in the dynamic of bricolage that informs the production of shipwreck texts in the Renaissance. The dramatic potential of both the disaster and the process of rebuilding is exploited throughout the century, culminating in a shipwreck tragedy. By the late Renaissance, shipwreck is not only the end, but often forms the beginning of a story.
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Anders, Torsten. Compositions Created with Constraint Programming. Edited by Roger T. Dean and Alex McLean. Oxford University Press, 2018. http://dx.doi.org/10.1093/oxfordhb/9780190226992.013.5.

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This chapter surveys music constraint programming systems, and how composers have used them. The chapter motivates why and explains how users of such systems describe intended musical results with constraints. This approach to algorithmic composition is similar to the way declarative and modular compositional rules have successfully been used in music theory for centuries as a device to describe composition techniques. This systematic overview highlights the respective strengths of different approaches and systems from a composer’s point of view, complementing other more technical surveys of this field. This text describes the music constraint systems PMC, Score-PMC, PWMC (and its successor Cluster Engine), Strasheela, and Orchidée—most are libraries of the composition systems PWGL or OpenMusic. These systems are shown in action by discussions of the composition processes of specific works by Jacopo Baboni Schilingi, Magnus Lindberg, Örjan Sandred, Torsten Anders, Johannes Kretz, and Jonathan Harvey.
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Forfar, Colin. Diagnosis and investigation in suspected heart disease. Edited by Patrick Davey and David Sprigings. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780199568741.003.0087.

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The past 20 years have seen significant changes in both the demographics and natural history of many cardiovascular diseases. Important reductions in case-fatality rates (such as in acute coronary syndromes) have resulted from improved diagnostics and treatment options and better understanding of natural history. For others (such as infective endocarditis), improvements have been limited and disappointing. While advances in therapy and the scientific evidence underpinning treatments have been crucial, the importance of accurate diagnosis has remained a key element for progress. Many of the principles needed for diagnosis are constant: the pre-eminence of a focused, accurate history, complete physical examination, and timely and relevant investigation endures. It is essential to have a secure knowledge of the strengths and limitations of interpretation of a frequently bewildering array of tests. Progress in this field has been rapid; advances in ultrasound, scintigraphy, and cardiac magnetic resonance stand out at the interface between structure and function central to good patient care.
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Sunardi, Christina. Afterword. University of Illinois Press, 2017. http://dx.doi.org/10.5406/illinois/9780252038952.003.0007.

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This concluding chapter reflects on the major points made throughout this book, discussing how individual artists have developed personal strategies for situating themselves within the constantly evolving constellations of personal, local, national, and global values that surround the negotiation of masculinity and femininity. Furthermore it returns to the subject of female power and how the performers maintain and make cultural space for the magnetic power of femaleness. Finally, and in spite of performers' concerns about the future of local tradition, the chapter expresses optimism about the future of the performing arts in Malang, demonstrating how a new generation of performers is actively engaging with the art.
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Deruelle, Nathalie, and Jean-Philippe Uzan. The free field. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198786399.003.0032.

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This chapter studies the structure of Maxwell’s equations in a vacuum and the action from which they are derived, while emphasizing the consequences of their gauge invariance. Gauge invariance, on the one hand, allows one of the components of the magnetic potential to be chosen freely. Here, the chapter shows how the gauge-invariant version of the Maxwell equations in the vacuum can also be derived directly by extremizing. On the other hand, the chapter argues that gauge invariance imposes a constraint on the initial conditions such that in the end the general solution has only two ‘degrees of freedom’. Finally, the chapter develops the Hamiltonian formalisms in the Maxwell theory and compares them to the formalisms using non-gauge-invariant or massive vector fields.
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Center, Langley Research, ed. Finite-perturbation intermediate-neglect-of-differential-overlap molecular orbital calculations of nuclear magnetic resonance spin-spin coupling constants for polycyclic aromatic hydrocarbons and aromatic nitrogen heterocyclics. Raleigh, N.C: North Carolina State University, 1985.

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Book chapters on the topic "Constant magnet"

1

Royet, John. "Straight Ends for Superconducting Dipole Magnet Using “Constant Perimeter” Geometry." In Supercollider 1, 399–402. Boston, MA: Springer US, 1989. http://dx.doi.org/10.1007/978-1-4613-0841-6_37.

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Gangopadhyay, Shruba, Artëm E. Masunov, Eliza Poalelungi, and Michael N. Leuenberger. "Prediction of Exchange Coupling Constant for Mn12 Molecular Magnet Using Dft+U." In Lecture Notes in Computer Science, 151–59. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-01973-9_17.

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Shibata, K., and K. Fujita. "Effect of Stiffness on Serrated Deformation at Very Low Temperatures Under Constant Loading Rate Conditions and its Computer Simulation." In 11th International Conference on Magnet Technology (MT-11), 737–42. Dordrecht: Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-009-0769-0_127.

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Pardasani, R. T., and P. Pardasani. "Paramagnetic Curie constant of diacetatomanganese(II)." In Magnetic Properties of Paramagnetic Compounds, Magnetic Susceptibility Data, Volume 1, 442–43. Berlin, Heidelberg: Springer Berlin Heidelberg, 2021. http://dx.doi.org/10.1007/978-3-662-62478-4_175.

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Pardasani, R. T., and P. Pardasani. "Weiss constant of bis(azido)pyrimidineiron(II)." In Magnetic Properties of Paramagnetic Compounds, Magnetic Susceptibility Data, Volume 2, 64–65. Berlin, Heidelberg: Springer Berlin Heidelberg, 2021. http://dx.doi.org/10.1007/978-3-662-62466-1_22.

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Pardasani, R. T., and P. Pardasani. "Weiss constant of bis(azido)pyrimidinecobalt(II)." In Magnetic Properties of Paramagnetic Compounds, Magnetic Susceptibility Data, Volume 2, 655–56. Berlin, Heidelberg: Springer Berlin Heidelberg, 2021. http://dx.doi.org/10.1007/978-3-662-62466-1_284.

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Janyška, Josef, and Marco Modugno. "Dynamical Example 3: Constant Magnetic Field." In Fundamental Theories of Physics, 555–68. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-89589-1_27.

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Pardasani, R. T., and P. Pardasani. "Paramagnetic Curie constant of bis(azido)pyrimidinemanganese(II)." In Magnetic Properties of Paramagnetic Compounds, Magnetic Susceptibility Data, Volume 1, 726–27. Berlin, Heidelberg: Springer Berlin Heidelberg, 2021. http://dx.doi.org/10.1007/978-3-662-62478-4_286.

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Pardasani, R. T., and P. Pardasani. "Paramagnetic Curie constant of tetra-μ-squaratooctaaquapyrazinetetramanganese(II)." In Magnetic Properties of Paramagnetic Compounds, Magnetic Susceptibility Data, Volume 1, 857–59. Berlin, Heidelberg: Springer Berlin Heidelberg, 2021. http://dx.doi.org/10.1007/978-3-662-62478-4_350.

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da Silva, E. C. F. "AlSb: dielectric constant." In New Data and Updates for IV-IV, III-V, II-VI and I-VII Compounds, their Mixed Crystals and Diluted Magnetic Semiconductors, 133. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-14148-5_77.

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Conference papers on the topic "Constant magnet"

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Fujita, Etsunori, Noritoshi Nakagawa, Norio Soga, Yumi Ogura, Eiji Sugimoto, and Shigeyuki Kojima. "An Experimental Study for Collision Stimulus Device Using a Magneto-Spring." In ASME 2001 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/detc2001/vib-21642.

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Abstract An experimental device that utilizes a magneto-spring and collision forces for a single-degree-of-freedom stimulus is proposed. By way of an actuator, the experimental device that was created in order to test the response created by a magneto-spring stimulus force arising from an impact force, applies a displacement stimulus to the magnet on one side, changing the distance between the magnets as well as the faced surface area of the magnets. The moving mass that, which supports the loaded mass and the magnet on other side, provides kinetic energy via the actuator and the magneto-spring. When the moving mass impact on impact plate, the impact plate turn over the motion of direction. This collision stimulus device is composed of a mechanisms having low damping, and being vibration device using a magneto-spring, it was verified through analysis and experimental studies to be a highly efficient shaker mechanism. In addition, when the stimulus energy from the shock vibration experiment is low, due to loaded mass move a quasi-zero spring constant or a low magnetic field gradient, it is thought that by generating anti-phase and a large relative displacement from a low frequency, a highly efficient shock stimulus mechanism can be achieved, even by applying the momentary impulse input as a disturbance, the magneto-spring, constant of non-linear characteristics and strong spring constant, elastic energy is used to create a symmetrical triangular shock wave. On one hand, the relation between the inputs and outputs that use variations in the magnetostatic energy created by changes in the distance between the repulsed magnets and the faced surface area was verified by studying the amount of work created by the magneto-spring stimulus energy of a repulsed magnet system during one vibration cycle of the moving mass attached to a moving magnet and a fixed magnet. It is seen that the input/output energy characteristics of the magneto-spring stimulus force are a highly efficient mechanism due to mageto-spring move in a strong magnetic field gradient. However, it is seen that mechanical amplification mechanism that utilizes a magneto-spring and collision forces are a highly efficient mechanism due to mageto-spring move in a low magnetic field gradient. The collision stimulus device using a quasi-zero spring constant and a elastic energy of magneto-spring changes sinusoidal wave, that vibration device applies, into a symmetrical triangular shock wave found in a large collision force and amplified amplitude, due to external disturbance which acts as a trigger, a elastic energy of magneto-spring and distance between impact plates optimized. However, it was realized that when a force greater than the prescribed amount is applied as resistance. As a results, the vibration energy is diminished, a shock wave change a symmetrical sinusoidal wave due to loaded mass move in a low magnetic field gradient or a quasi-zero spring constant.
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Chen, Lele, Changchun Zou, Dianqing Sun, and Zhaobin Gu. "Design of A Magnet with Constant gradient field for Nuclear Magnetic Resonance." In 2015 3rd International Conference on Mechanical Engineering and Intelligent Systems. Paris, France: Atlantis Press, 2015. http://dx.doi.org/10.2991/icmeis-15.2015.183.

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Bai, Ying, Guozheng Tao, and Minghai Yuan. "Research on Permanent Magnet Constant Voltage Device for Vehicle." In 2010 International Conference on Measuring Technology and Mechatronics Automation (ICMTMA 2010). IEEE, 2010. http://dx.doi.org/10.1109/icmtma.2010.332.

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Tsutomu, M., K. Masanori, T. Fumiaki, K. Masashi, and Y. Hajime. "Cylindrical moving magnet type linear actuator having large motor constant." In INTERMAG Asia 2005: Digest of the IEEE International Magnetics Conference. IEEE, 2005. http://dx.doi.org/10.1109/intmag.2005.1463535.

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Lin, D., P. Zhou, and Z. J. Cendes. "In-depth study of the torque constant for permanent magnet machines." In Energy Society General Meeting. IEEE, 2008. http://dx.doi.org/10.1109/pes.2008.4596427.

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Armando, Eric, Aldo Boglietti, Salvatore Musumeci, Sandro Rubino, Enrico Carpaneto, and Daniele Martinello. "Measurement Technique for the Permanent Magnet Rotor Thermal Time Constant Determination." In 2020 IEEE International Conference on Industrial Technology (ICIT). IEEE, 2020. http://dx.doi.org/10.1109/icit45562.2020.9067271.

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Armando, Eric, Aldo Boglietti, Salvatore Musumeci, Sandro Rubino, Enrico Carpaneto, and Daniele Martinello. "Measurement of Rotor Thermal Time-Constant for Permanent Magnet Synchronous Machines." In 2020 IEEE Energy Conversion Congress and Exposition (ECCE). IEEE, 2020. http://dx.doi.org/10.1109/ecce44975.2020.9235959.

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Krishan, Ramsakal, Kundan Kumar, and Rakesh Roy. "Comparative Analysis of Constant Torque Angle Control and Constant Mutual Flux Linkage Control of Permanent Magnet Synchronous Motor." In 2018 2nd International Conference on Energy, Power and Environment: Towards Smart Technology (ICEPE). IEEE, 2018. http://dx.doi.org/10.1109/epetsg.2018.8658931.

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Gui-Jia Su, Lixin Tang, and Zhiqiao Wu. "Extended constant-torque and constant-power speed range control of permanent magnet machine using a current source inverter." In 2009 IEEE Vehicle Power and Propulsion Conference (VPPC). IEEE, 2009. http://dx.doi.org/10.1109/vppc.2009.5289863.

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Amiri, Navid, Mehrdad Chapariha, Seyyedmilad Ebrahimi, Juri Jatskevich, and Liwei Wang. "Constant parameter VBR model of permanent magnet synchronous machine wind generation system." In 2015 IEEE Power & Energy Society General Meeting. IEEE, 2015. http://dx.doi.org/10.1109/pesgm.2015.7286439.

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Reports on the topic "Constant magnet"

1

Dumont, R., M. Coyle, D. Oneschuk, and J. Potvin. Magnetic decay constant (TAU) with electromagnetic anomalies, Pamour, Ontario. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2002. http://dx.doi.org/10.4095/213900.

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Dumont, R., M. Coyle, D. Oneschuk, and J. Potvin. Magnetic decay constant (TAU) with electromagnetic anomalies, Buskegau River, Ontario. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2002. http://dx.doi.org/10.4095/220503.

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Dumont, R., M. Coyle, D. Oneschuk, and J. Potvin. Magnetic decay constant (TAU) with electromagnetic anomalies, Manning Lake, Ontario. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2002. http://dx.doi.org/10.4095/213890.

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Dumont, R., M. Coyle, D. Oneschuk, and J. Potvin. Magnetic decay constant (TAU) with electromagnetic anomalies, Kamiskotia Lake, Ontario. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2002. http://dx.doi.org/10.4095/213899.

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Peyghambarian, Nasser, Robert A. Norwood, and Andre Persoons. In-Fiber Magneto-Optic Devices Based on Ultrahigh Verdet Constant Organic Materials and Holey Fibers. Fort Belvoir, VA: Defense Technical Information Center, February 2009. http://dx.doi.org/10.21236/ada495425.

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Galili, Naftali, Roger P. Rohrbach, Itzhak Shmulevich, Yoram Fuchs, and Giora Zauberman. Non-Destructive Quality Sensing of High-Value Agricultural Commodities Through Response Analysis. United States Department of Agriculture, October 1994. http://dx.doi.org/10.32747/1994.7570549.bard.

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The objectives of this project were to develop nondestructive methods for detection of internal properties and firmness of fruits and vegetables. One method was based on a soft piezoelectric film transducer developed in the Technion, for analysis of fruit response to low-energy excitation. The second method was a dot-matrix piezoelectric transducer of North Carolina State University, developed for contact-pressure analysis of fruit during impact. Two research teams, one in Israel and the other in North Carolina, coordinated their research effort according to the specific objectives of the project, to develop and apply the two complementary methods for quality control of agricultural commodities. In Israel: An improved firmness testing system was developed and tested with tropical fruits. The new system included an instrumented fruit-bed of three flexible piezoelectric sensors and miniature electromagnetic hammers, which served as fruit support and low-energy excitation device, respectively. Resonant frequencies were detected for determination of firmness index. Two new acoustic parameters were developed for evaluation of fruit firmness and maturity: a dumping-ratio and a centeroid of the frequency response. Experiments were performed with avocado and mango fruits. The internal damping ratio, which may indicate fruit ripeness, increased monotonically with time, while resonant frequencies and firmness indices decreased with time. Fruit samples were tested daily by destructive penetration test. A fairy high correlation was found in tropical fruits between the penetration force and the new acoustic parameters; a lower correlation was found between this parameter and the conventional firmness index. Improved table-top firmness testing units, Firmalon, with data-logging system and on-line data analysis capacity have been built. The new device was used for the full-scale experiments in the next two years, ahead of the original program and BARD timetable. Close cooperation was initiated with local industry for development of both off-line and on-line sorting and quality control of more agricultural commodities. Firmalon units were produced and operated in major packaging houses in Israel, Belgium and Washington State, on mango and avocado, apples, pears, tomatoes, melons and some other fruits, to gain field experience with the new method. The accumulated experimental data from all these activities is still analyzed, to improve firmness sorting criteria and shelf-life predicting curves for the different fruits. The test program in commercial CA storage facilities in Washington State included seven apple varieties: Fuji, Braeburn, Gala, Granny Smith, Jonagold, Red Delicious, Golden Delicious, and D'Anjou pear variety. FI master-curves could be developed for the Braeburn, Gala, Granny Smith and Jonagold apples. These fruits showed a steady ripening process during the test period. Yet, more work should be conducted to reduce scattering of the data and to determine the confidence limits of the method. Nearly constant FI in Red Delicious and the fluctuations of FI in the Fuji apples should be re-examined. Three sets of experiment were performed with Flandria tomatoes. Despite the complex structure of the tomatoes, the acoustic method could be used for firmness evaluation and to follow the ripening evolution with time. Close agreement was achieved between the auction expert evaluation and that of the nondestructive acoustic test, where firmness index of 4.0 and more indicated grade-A tomatoes. More work is performed to refine the sorting algorithm and to develop a general ripening scale for automatic grading of tomatoes for the fresh fruit market. Galia melons were tested in Israel, in simulated export conditions. It was concluded that the Firmalon is capable of detecting the ripening of melons nondestructively, and sorted out the defective fruits from the export shipment. The cooperation with local industry resulted in development of automatic on-line prototype of the acoustic sensor, that may be incorporated with the export quality control system for melons. More interesting is the development of the remote firmness sensing method for sealed CA cool-rooms, where most of the full-year fruit yield in stored for off-season consumption. Hundreds of ripening monitor systems have been installed in major fruit storage facilities, and being evaluated now by the consumers. If successful, the new method may cause a major change in long-term fruit storage technology. More uses of the acoustic test method have been considered, for monitoring fruit maturity and harvest time, testing fruit samples or each individual fruit when entering the storage facilities, packaging house and auction, and in the supermarket. This approach may result in a full line of equipment for nondestructive quality control of fruits and vegetables, from the orchard or the greenhouse, through the entire sorting, grading and storage process, up to the consumer table. The developed technology offers a tool to determine the maturity of the fruits nondestructively by monitoring their acoustic response to mechanical impulse on the tree. A special device was built and preliminary tested in mango fruit. More development is needed to develop a portable, hand operated sensing method for this purpose. In North Carolina: Analysis method based on an Auto-Regressive (AR) model was developed for detecting the first resonance of fruit from their response to mechanical impulse. The algorithm included a routine that detects the first resonant frequency from as many sensors as possible. Experiments on Red Delicious apples were performed and their firmness was determined. The AR method allowed the detection of the first resonance. The method could be fast enough to be utilized in a real time sorting machine. Yet, further study is needed to look for improvement of the search algorithm of the methods. An impact contact-pressure measurement system and Neural Network (NN) identification method were developed to investigate the relationships between surface pressure distributions on selected fruits and their respective internal textural qualities. A piezoelectric dot-matrix pressure transducer was developed for the purpose of acquiring time-sampled pressure profiles during impact. The acquired data was transferred into a personal computer and accurate visualization of animated data were presented. Preliminary test with 10 apples has been performed. Measurement were made by the contact-pressure transducer in two different positions. Complementary measurements were made on the same apples by using the Firmalon and Magness Taylor (MT) testers. Three-layer neural network was designed. 2/3 of the contact-pressure data were used as training input data and corresponding MT data as training target data. The remaining data were used as NN checking data. Six samples randomly chosen from the ten measured samples and their corresponding Firmalon values were used as the NN training and target data, respectively. The remaining four samples' data were input to the NN. The NN results consistent with the Firmness Tester values. So, if more training data would be obtained, the output should be more accurate. In addition, the Firmness Tester values do not consistent with MT firmness tester values. The NN method developed in this study appears to be a useful tool to emulate the MT Firmness test results without destroying the apple samples. To get more accurate estimation of MT firmness a much larger training data set is required. When the larger sensitive area of the pressure sensor being developed in this project becomes available, the entire contact 'shape' will provide additional information and the neural network results would be more accurate. It has been shown that the impact information can be utilized in the determination of internal quality factors of fruit. Until now,
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