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Before 1905 Poincare defined Lorentz’s local time by means of a thought experiment in which observers synchronize their watches with light signals. In 1905 Einstein presented a similar thought experiment in his relativity paper. The similarity between Poincare’s and Einstein’s thought experiment is striking. I suggest that Poincare’s thought experiment before 1905 may have indirectly assisted Einstein in formulating the theory that he had already discovered during the seven years of reflections between 1898 and 1905.

This paper reports the results of an experiment performed at the CERN ISR to search for new particles, produced in pp collisions at √s=53 GeV, which decay into two long‐lived hadrons (i.e. π+, π−, K+, K−, p or ?).

In the paper we consider the dynamic elastic oligopolistic market equilibrium problem in presence of production excesses and show the equivalence between the generalized Cournot-Nash principle and a quasi-variational inequality. Moreover, we present existence and regularity results for equilibrium solutions. Finally, we introduce a long term memory in order to take into account the delay effects in the noncooperative market.

We present a quantum‐like model of decision making in games of the Prisoner’s Dilemma type. By this model the brain processes information by using representation of mental states in complex Hilbert space. Driven by the master equation the mental state of a player, say Alice, approaches an equilibrium point in the space of density matrices. By using this equilibrium point Alice determines her mixed (i.e., probabilistic) strategy with respect to Bob. Thus our model is a model of thinking through decoherence of initially pure mental state. Decoherence is induced by interaction with memory and external environment. In this paper we study (numerically) dynamics of quantum entropy of Alice’s state in the process of decision making. Our analysis demonstrates that this dynamics depends nontrivially on the initial state of Alice’s mind on her own actions and her prediction state (for possible actions of Bob.)

For measurement of the water-cut of the fluid in a low production horizontal well, a combined capacitance sensor is designed which is composed of the cylindrical capacitance sensor and the coaxial capacitance sensor. The two sensors are of parallel connnection in the electric circuit. Because of parallel connnection of the two capacitance sensors, the surface area of the combined sensor increases. Thus in the non-stratified flow, the oil bubbles are apt to touch the sensor and its measurement resolution is improved. And in the stratified flow, the cylindrical capacitance which plays a leading role is sensitive to the hight of oil-water interface. The structure of the sensor is introduced in the paper. The electric field simulation is conducted and the sensor response in the oil/water stratified flow and bubble flow are given. Static experiment and dynamic experiment of the sensor are carried out and the response at the different flowrate and water cut is obtained. The results show that the combined capaci...

Real photon beams in the energy region up to several ten MeV provide a good opportunity for experimental studies of astrophysical nucleosynthesis caused by the electromagnetic interactions as well as the weak interactions. In this paper development of real photon sources at low energies is reviewed, and a recent experimental work on the photonuclear reactions of 4He with new‐generation γ‐ray sources by the laser Compton‐scattering method is presented.

Fuel efficiency requirements demand lightweight construction of vehicle body parts. The usage of advanced high strength steels permits a reduction of sheet thickness while still maintaining the overall strength required for crash safety. However, damage, internal defects (voids, inclusions, micro fractures), microstructural defects (varying grain size distribution, precipitates on grain boundaries, anisotropy) and surface defects (micro fractures, grooves) act as a concentration point for stress and consequently as an initiation point for failure both during deep drawing and in service. Considering damage evolution in the design of car body deep drawing processes allows for a further reduction in material usage and therefore body weight. Preliminary research has shown that a modification of load paths in forming processes can help mitigate the effects of damage on the material.This paper investigates the load paths in Nakajima tests of a DP800 dual phase steel to research damage in deep drawing processes. Investigation is done via a finite element model using experimentally validated material data for a DP800 dual phase steel. Numerical simulation allows for the investigation of load paths with respect to stress states, strain rates and temperature evolution, which cannot be easily observed in physical experiments. Stress triaxiality and the Lode parameter are used to describe the stress states. Their evolution during the Nakajima tests serves as an indicator for damage evolution. The large variety of sheet metal forming specific load paths in Nakajima tests allows a comprehensive evaluation of damage for deep drawing. The results of the numerical simulation conducted in this project and further physical experiments will later be used to calibrate a damage model for simulation of deep drawing processes.Fuel efficiency requirements demand lightweight construction of vehicle body parts. The usage of advanced high strength steels permits a reduction of sheet thickness while still maintaining the overall strength required for crash safety. However, damage, internal defects (voids, inclusions, micro fractures), microstructural defects (varying grain size distribution, precipitates on grain boundaries, anisotropy) and surface defects (micro fractures, grooves) act as a concentration point for stress and consequently as an initiation point for failure both during deep drawing and in service. Considering damage evolution in the design of car body deep drawing processes allows for a further reduction in material usage and therefore body weight. Preliminary research has shown that a modification of load paths in forming processes can help mitigate the effects of damage on the material.This paper investigates the load paths in Nakajima tests of a DP800 dual phase steel to research damage in deep drawing processes....

The aim of this paper is to calculate the fine structure of the optical energy levels scheme of BaLiF3:Ni2+ taken into account besides the spin‐orbit interaction, also the spin‐spin, orbit‐orbit and spin‐other‐orbit interactions. The numerical theoretical crystal field parameters were computed using the model exchange charge calculations of crystal field, taking into account the effects of the covalent bond formation between the Ni2+ and F− ions. The Hamiltonian of the BaLiF3:Ni2+ system has been diagonalized in a complete basis set spanned by all wave functions of the 3d8 electron configuration. The comparison of the calculated energy levels with experimental data gives a satisfactory agreement, which confirms the model and used method.

The paper presents the proprietary know-how of the autowave analysis which occur at deformation of solids. Traditional techniques of X-ray diffraction analysis are described to detect main autowave properties, i.e. wave propagation velocity and length.

The ultrasonic reflectivity of a lubricant layer between two solid bodies depends on the ultrasonic frequency, the acoustic properties of the liquid and solid, and the layer thickness. In this paper, ultrasonic reflectivity measurements are used as a method for determining the thickness of lubricating films in bearing systems. An ultrasonic transducer is positioned on the outside of a bearing shell such that the wave is focused on the lubricant film layer. For a particular lubricant film the reflected pulse is processed to give a reflection coefficient spectrum. The lubricant film thickness is then obtained from either the layer stiffness or the resonant frequency. The method has been validated using static fluid wedges and the elastohydrodynamic film formed between a ball sliding on a flat. Film thickness values in the range 50–500 nm were recorded which agreed well with theoretical film formation predictions.

The fan is one of the main noise sources of an aircraft engine. To reduce fan noise and provide liner optimization in the inlet it is necessary to research modal structure of the fan noise. The present paper contains results of acoustic tests on installation for mode generation that consists of 34-channel generator and the inlet updated for mounting of 100 microphones, the experiments were provided in new anechoic chamber of Perm National Research Polytechnic University, the engine with the same inlet was also tested in the open test bench conditions, and results of the fan noise modal structure are presented. For modal structure educting, all 100 channels were synchronously registered in a given frequency range. The measured data were analyzed with PULSE analyzer using fast Fourier transform with a frequency resolution 8..16 Hz. Single modes with numbers from 0 to 35 at frequencies 500; 630; 800; 1000; 1250; 1600 Hz and different combinations of modes at frequencies 1000, 1600, 2000, 2500 Hz were set dur...

In this paper, the results of measurements of nickel coating thickness are presented. Ni coatings were deposited onto zirconium alloy Zr-1Nb and Si wafers by dc magnetron sputtering. The thickness of Ni coatings was measured by scanning electron microscopy (SEM), ball abrasion method and non-destructive X-ray diffraction (XRD) method. The developed technique of determination of coating uniformity by grazing incidence XRD method was shown. The estimation of uniformity of Ni coatings with a thickness from 0.5 to 2 µm was performed. The distribution map of the coating thickness over surface of 20×20 mm was constructed. The deposited coating with higher thickness of 2 µm has 10% deviation of thickness.In this paper, the results of measurements of nickel coating thickness are presented. Ni coatings were deposited onto zirconium alloy Zr-1Nb and Si wafers by dc magnetron sputtering. The thickness of Ni coatings was measured by scanning electron microscopy (SEM), ball abrasion method and non-destructive X-ray diffraction (XRD) method. The developed technique of determination of coating uniformity by grazing incidence XRD method was shown. The estimation of uniformity of Ni coatings with a thickness from 0.5 to 2 µm was performed. The distribution map of the coating thickness over surface of 20×20 mm was constructed. The deposited coating with higher thickness of 2 µm has 10% deviation of thickness.

We present a methodology to evaluate the moments of the Boltzmann collision term, in a general automated way, using the computer algebra software Mathematica. Based on Grad's distribution function with 26-moments, we compute the non-linear production terms for a simple gas and a granular gas, and the linear production terms for a binary mixture of gases. The results can be shown for general interaction potential, but, in this paper, they are given only for hard-sphere interaction potential.

The paper is based on the ionospheric variations in terms of vertical total electron content (VTEC) for the period from January 2012 to December 2013 based on the analysis of dual frequency signals from the Global Positioning System (GPS) satellites recorded at ground stations Surat (21.16°N, 72.78°E Geog.), situated under the northern crest of the equatorial ionization anomaly region (EIA) and other three International GNSS Service (IGS) stations Bangalore (13.02°N, 77.57°E Geog.), Hyderabad (17.25°N, 78.30°E Geog.), and Lucknow (26.91°N, 80.95°E Geog.) in India. We describe the diurnal and seasonal characteristics. It was observed that GPS-TEC reaches its maximum value between 12:00 and 16:00 IST. Further, Seasonal variations of GPS-TEC is categorized into four seasons, i.e., March equinox (February, March, and April), June solstice (May, June, and July), September equinox (August, September, and October) and December solstice (November, December and January). The forenoon rate of production in Lucknow (beyond EIA crest) is faster than Bangalore, Hyderabad and Surat station. It is found that September equinox shows GPS-TEC slightly higher than the March equinox, followed by June solstice and the lowest GPS-TEC are in winter solstice at four stations. The equinoctial asymmetry clearly observed in the current study. Also GPS-TEC shows a semiannual variation.

With the booming in the manufacturing sector of shoe, garments and toy, etc. in pearl region, training the usage of various facilities and design the facility layout become crucial for the success of industry companies. There is evidence that the use of virtual training may provide benefits in improving the effect of learning and reducing risk in the physical work environment. This paper proposed an advanced web‐based training environment that could demonstrate the usage of a CNC machine in terms of working condition and parameters selection. The developed virtual environment could provide training at junior level and advanced level. Junior level training is to explain machining knowledge including safety factors, machine parameters (ex. material, speed, feed rate). Advanced level training enables interactive programming of NG coding and effect simulation. Operation sequence was used to assist the user to choose the appropriate machining condition. Several case studies were also carried out with animation of milling and turning operations.

This paper reports and discusses the thermal and kinetic behaviour of elastomer flow inside an extrusion die. The reaction progress through the runner was modeled by using a particle tracking technique. The aim is to analyze viscous dissipation phenomena to control scorch arisen, improve the rubber compound curing homogeneity and reduce the heating time in the mould using the progress of the induction time. The heat and momentum equations were solved in three dimensions with Ansys Polyflow. A particle tracking technique was set up to calculate the reaction progress. Several simulations were performed to highlight the influence of process parameters and geometry modifications on the rubber compound thermal and cure homogeneity.

We present in this paper some experimental results about the initiation of homogeneous explosives. We show that the process generally adopted for this initiation is not checked at the used level of pressure. According to some previous studies, we propose here an initiation process by hot spots.

Solder paste is the most widely used interconnection material in the electronic assembly process for attaching electronic components/devices directly onto the surface of printed circuit boards, using stencil printing process. This paper evaluates the performance of three different commercially available Sn‐Ag‐Cu solder pastes formulated with different particle size distributions (PSD), metal content and alloy composition. A series of stencil printing tests were carried out using a specially designed stencil of 75 μm thickness and apertures of 300×300 μm2 dimension and 500 μm pitch sizes. Solder paste printing behaviors were found related to attributes such as slumping and surface tension and printing performance was correlated with metal content and PSD. The results of the study should benefit paste manufacturers and SMT assemblers to improve their products and practices.

Nonplanar surface geometries of components are frequently encountered in real ultrasonic inspection situations. When a flexible array is used instead of rigid array transducers to fit the complex surface profile, the locations of array elements should be known to compute the delay time necessary for adaptive beam focusing. An alternative method is to employ the time reversal focusing technique that does not require a prior knowledge about the properties and structures of the specimen and the transducer. In this paper, a time reversal method is applied to simulate beam focusing of flexible arrays and imaging of point-like defects contained in specimens with nonplanar surface geometry. Quantitative comparisons are made for the performance of a number of array techniques in terms of the ability to focus and image five point-like reflectors positioned at regular intervals. The sinusoidal profile array studied here exhibits almost the same image quality as the flat, reference case.

In this paper, an attempt has been made to forecast two major exchange rates USDAUD (US Dolar versus Australian Dolar currency) and USDJPY (US Dolar versus Japanese Yen currency) using Non-Linear Autoregressive (NAR) with monthly period data from January 1975 to April 2014. The data is collected from Bank of England. The ecchange rates forecasting use 3 layer models with input, hidden and output layer. The number of hidden nodes are 2, and 3 for USDAUD and USDJPY respectively. Levernberg-Marquardt (LM) learning algorithm is used to do training. The accuracy result for the experiments showed that Dstat parameter for USDAUD (60.56%) is a bit higher than industry standard accuracy but lower than industry standard accuracy for USDJPY (52.11%). The MSE result is 0.3239 for USDAUD and 7.518 for USDJPY.

Stabilization of an electrostatic flute‐type instability occurring in a simple magnetic mirror by feedback techniques is discussed. In the first part of the paper a diffuse plasma is considered. The effect of varying the locations of the sensing and suppressing systems is found to alter the stability threshold significantly. In the second part a sharp‐boundary plasma is considered and phase shift and frequency response are included in the feedback terms.

In the basic tokamak experiment, the copper shell is a highly‐satisfactory feedback control device. For certain extensions of the tokamak operation — for example, to compression heating — it is, however, convenient to remove the copper shell. External feedback control of the equilibrium position is then a natural substitute. A more complex problem is the feedback stabilization of MHD modes. The interchange instabilities, against which linear magnetic feedback is ineffective, are fortunately stabilized by the minimum‐average‐B property of the toroidal tokamak. Feedback stabilization of a type of thermal instability that results in major‐radius shifts is the principal topic of this paper.

Digital speckle pattern interferometry (DSPI) is a kind of interferometric technique for the measurement of deformation of objects. Temporal phase‐shifting (TPS) technique has been applied for extracting quantitative deformation data from the fringe patterns. Butterworth low‐pass filter based on discrete cosine transform (DCT), a frequency domain filter, has been applied to remove the fringe patterns noise in this study. It is shown that the Butterworth filter is able to remove the fringe patterns noise to the large extent. Theoretical and experimental results on an edge clamped circular aluminum plate subjected to a central concentrated loading for out‐of‐plane displacement measurement are presented in this paper.

A new secure steganography, which is based on Huffman encoding and modified quantized discrete cosine transform (DCT) coefficients, is provided in this paper. Firstly, the cover image is segmented into 8×8 blocks and modified DCT transformation is applied on each block. Huffman encoding is applied to code the secret image before embedding. DCT coefficients are quantized by modified quantization table. Inverse DCT(IDCT) is conducted on each block. All the blocks are combined together and the steg image is finally achieved. The experiment shows that the proposed method is better than DCT and Mahender Singh’s in PSNR and Capacity.

This paper discusses some aspects of the superconductivity of rare‐earths and actinides :1) The pressure dependence of the superconductivity of Lanthanum is explained under the assumption of a valency a little smaller than 3. Some new experimental evidences could support this assumption. Superconductivity of Cerium metal and alloys is briefly reviewed.2) A simple model for actinides metals and alloys is presented for explaining the occurrence of localized magnetism only for Curium and the superconductivity of actinides impurities in Lanthanum.

This paper describes the 80 MeV (protons) cyclotron built for the University of Louvain. The machine features variable energy and can also accelerate deuterons, 3He and alpha particles. Design and construction were completed within 40 months and first operational results are reported.

We must understand the physics of strongly interacting electrons if we are to have a fundamental understanding of magnetism. This paper treats the simplest model with this property — the Hubbard model. The moments of the spectral weight function (SWF), derived by Harris and Lange, are calculated in the atomic limit. These moments are used to generate an approximate SWF (including lifetime effects). The paramagnetic and ferromagnetic ground state energies are calculated and compared. There is no restriction on the electron density.

Prompting this study was the possible use of a time‐varying electrical current within the magnetic alloy material of large interconnected memory arrays to simplify the wiring needed for coincident current switching and for nondestructive readout. This paper reports details on the following effects of low‐frequency current in the direction of magnetization in 50% Ni–Fe tape: (1) The reduction in average frictional field of a major domain wall, as caused by the cross‐field of the current, is found to decrease with depth from the tape surface as expected. The electron drift itself did not measurably affect the wall friction. (2) The measured Rayleigh hysteresis effect, shown to suffer a reduction in restoring field with cross‐field interaction, is compared with a revised form of Baldwin's theoretical model to give further understanding of the mechanism for the interaction. (3) The threshold for low‐field switching (H

When one writes into a continuous planar film memory or a wire memory, the stray field from the pole distribution is generally comparable to or in some regions greater than the applied field from the striplines. In this paper, it is shown that if a keeper is used or if the poles are confined to a narrow strip, the problem can be reduced (via a Taylor series) to a local linear differential equation solvable by hand. The theory is used to calculate the hard axis component of magnetization along a plated wire and to calculate the locus of the domain wall in a planar oligatomic film memory as a function of word and digit fields. The length of the domain is compared with Lorentz microscope data.

The ac‐anhysteretic process is the elementary process of recording. In an earlier paper, the author has presented a mean field theory that relates the anhysteretic remanence curve Mar(H) to the material structural properties.1 In particular, at temperature T=0, the initial slope of Mar(H), Xar, may be finite only for certain material structures and is then determined by the dynamic rather than the static interaction fields. This concept is now extended to T>0, using a result of Jaep. In principle, the assumed mechanism may be described in terms of a feedback control process with the interaction fields acting as feedback link. The control function is a step function at T=0; it becomes continuous for T>0. The theory yields in considerable detail the characteristic features of the experimental data. The most important difference between the author's view and other theories appears to be that the latter either ignore or oversimplify the role of the dynamic interaction fields and thereby lose most of the relat...

The recent development of Rare Earth permanent magnets requires a revision of the application possibilities of permanent magnets in rotating machinery. This paper contributes some ideas on how to make the best use of their characteristics. The two important areas of application, the stationary magnet structure and rotating magnet structure, are discussed separately. Electrically excited machines are compared to those with permanent magnet excitation of both the conventional magnet and the new magnet types. The results of these considerations are twofold depending upon whether the magnets are used in stationary magnet structures or in rotating magnet structures. Many of the electromagnetic design concepts, which have been developed for ceramic magnet motors, also apply for the new magnets when they are used in stationary magnets (1) provide more than twice the flux densities at higher coercive forces, (2) will withstand more than twice the demagnetization forces, and (3) show much improved thermal properties. New design concepts will have to be developed for the application of Rare Earth magnets in rotating field structures. Present design concepts have mainly been worked out for Alnico 5–7, a material with an extremely high remanence flux density but a very low coercive force. They do not fit the Rare Earth magnets. One possible design concept is outlined in the paper. The significant difference between an Alnico magnet design and a Rare Earth magnet design lies in the volume of the magnets. The new magnets allow more rotor volume to be used for the mechanical structure resulting for a more reliable and stronger rotor construction. It is expected that the new magnets significantly broaden the range of applications for permanent magnets in rotating machinery.

Motion of magnetic domain walls in magnetic bubble domain materials is discussed in this paper. A steady‐state solution for wall velocity in a magnetic material with orthorhombic anisotropy is used to obtain the conventional expression for the domain wall mobility. After reviewing the experimental situation, it is concluded that the mobility depends in a predictable way on wall width but that its detailed behavior otherwise is not well understood. Limiting wall velocities, nonlinear velocity‐field behavior, and wall inertial effects are considered, and important consequences of the orthorhombic anisotropy appear here; supporting experimental results for these effects are reviewed. Wall motion damping due to anisotropic energy levels in several of the magnetic rare earths is shown to be a limiting factor in obtaining high mobility materials. Other factors which have been shown to be significant, such as surface smoothness, thermal annealing, and irradiation with X‐rays, are also discussed. Finally, express...

This paper describes the conceptual design of a highly reliable 108‐Bit Bubble Domain Memory for the Space Program. The Memory has random access to blocks of closed‐loop shift registers, and utilizes self‐contained bubble domain chips with on‐chip decoding. Tradeoff studies show that the highest reliability and lowest power dissipation is obtained when the memory is organized on a bit‐per‐chip basis. The final design, has 800 bits/register, 128 registers/chip, 16 chips/plane, and 112 planes, of which only seven are activated at a time. A word has 64 data bits +32 checkbits, used in a “16‐adjacent” code to provide correction of any combination of errors in one plane. 100 KHz maximum rotational frequency keeps power low (≤ 25 watts) and also allows asynchronous operation. Data rate is 6.4 megabits/sec, access time is 200 μsec to an 800‐word block and an additional 4 msec (average) to a word.

This paper describes the fabrication and operation of a 52‐bit bubble domain memory chip designed to test the concept of on‐chip magnetic decoding. Access to one of the chip's four shift registers for the read, write, and clear functions is by means of bubble domain decoders utilizing the interaction between a conductor line and a bubble. All other functions are performed by a permalloy overlay driven by an external rotating field. The metallurgy consists of 200 A evaporated permalloy for magnetoresistive sensors. 4000 A electroplated permalloy for propagation etc., and 6000 A electroplated copper for control lines.

The storage of information in present day computer systems is shared between high‐speed, high‐cost memories and low‐speed, low‐cost mechanical storage devices. With the advent of cheap bulk memory technology one can envision a storage hierarchy with three levels of storage: buffer, memory, and a mechanical backing store. The individual cost and performance characteristics of the three technologies involved affect the overall computer system cost‐performance. In fact, it is the judicious selection of technologies and system configurations which leads to a well designed storage system. This paper first describes the automatic management of information in a three level storage system where the objective is to keep current information in the fastest device and the rest of the information in the slower devices. Then the evaluation of the storage systems is described for a multiprogramming environment where total system dollars per instruction executed is the criterion for system cost‐performance. Finally, two ...

This paper presents the major highlights of past experimental work and current knowledge on the superconducting critical temperatures of the transition elements, their alloys and compounds. The survey includes materials such as: the solid solution alloys of the d‐band transition metals; intermetallic compounds of the sigma, alpha‐manganese and Laves phases; superconducting compounds of ferromagnetic elements and Group 3 elements; and high critical temperature materials of the sodium chloride and β‐tungsten structures.

This paper discusses the tolerances imposed on certain imperfections in the TRIUMF magnetic field by the resonances νx = 1/1, 2/2, 3/2 and 6/4, νz = 1/2 and νx − νz = 1, and by the height of the equilibrium orbit. A method of calculating harmonic coil settings to centre a beam of wide phase width is described.

The high‐intensity beam of LAMPF requires careful control of beam loss to minimize activation of the beam channel. This paper describes a beam‐spill control system now in operation which limits the average beam loss to an amount allowed by activation criteria, without severely restricting accelerator tune‐up and diagnostics work. This average loss is maintained by downward modulation of the beam‐pulse width and repetition rate until the loss‐producing fault is corrected. Binary and analog signals describing the action are sent to the Central Control Computer where decisions regarding corrective measures can be made by either the operator or the computer. The computer can test all beam‐spill monitors simultaneously while the machine is in operation.

After 20 years of operation as a conventional synchrocyclotron producing 0.4 ?A time average internal beam current of protons (increased to 1.6 ?A in 1967) of ~ 385 MeV, we stopped operation in September 1970 for the major modification for which we have been planning since 1965. The major study program and the conversion project are supported by a $ 3.9 M grant from the NSF. The conversion retains the basic cyclotron magnet (2000 tons of Fe and ~ 300 tons of Cu coils), but adds a 10-in. thick Fe band around the outside magnet perimeter to lower the return path reluctance. A new larger vacuum chamber is used, with auxilliary excitation coils. Pole iron within 30 in. of the median plane is replaced by a new configuration which includes N=3 symmetry sector iron with a small median plane gap. = 18 kG near the center and 20 kG near 80 in. radius. Strong azimuthal magnetic field flutter begins at < 2 in. radius to give strong focusing ?z, and ?r?1. We expect to obtain ~ 550 MeV proton energy, with high extraction efficiency for a 10 to 40 ?A time average external beam (~ 50% duty factor), when operation starts later this year. Additional details are given in companion papers in these Proceedings. The system will still be a synchrocyclotron and will have a 300 Hz FM repetition rate, with a new RF system, etc.

In the focus of attention at the present time are the new rare earth‐cobalt‐based magnet alloys. This paper is primarily a qualitative review of the physical phenomena controlling their behavior and of the materials problems these magnets have posed. It also provides an outlook at possibilities for the development of still better or cheaper permanent magnets which current research on rare earth‐ transition metal alloys appears to provide. The origins of the magnetic moments and the crystal anisotropy of rare earth‐transition metal phases are discussed. Alternative concepts of the causes of coercivity in powders and sintered bodies are analyzed. Some basic aspects of the sintering of R‐Co compacts and the magnetic hardening of R–Co–Cu alloys in the massive state are reviewed. Specific problems related to particular alloys and applications of the magnets are pointed out. The conclusion is drawn that the new family of permanent magnets now emerging rivals in complexity both the Alnicos and the ferrites together. There are many development opportunities for the future, and we can expect that, eventually, magnets based on high‐anisotropy alloys containing rare earths will be offered in a variety of grades, covering a wide range of properties and prices, and that they will be produced by several drastically different methods.

This paper discusses the system developed to control the 2 MW 23 MHz RF system at TRIUMF. Included are means of pulsing through the multipactoring region; RF accelerating voltage amplitude and phase control; provision of self‐excited and driven modes of operation; fine tuning of the resonators; phase and amplitude control of third harmonic voltage for flat‐topping of the RF waveform. Results obtained with a prototype control system on the central region cyclotron are included.

The present paper is devoted to a study of TE surface modes along a ferrite‐dielectric interface, the ferrite magnetization being parallel to the interface. For a transverse propagation with respect to magnetization, two TE‐modes can be found. These unidirectional modes are respectively forward and reverse. The “magnetostatic mode” includes the Damon‐Eshbach mode. The “dynamic mode”, which presents a very wide bandwidth, includes the mode recently described by Hines. Our investigation, carried out on a schematic configuration, gives simple results, which clearly point out the physical behaviour of these very interesting modes.

This paper discusses spin excitation effects in superconductors with an emphasis on experiment. First, a review is presented of the superconductivity in dilute alloy systems which exhibit localized spin fluctuations associated with resonant impurity states. It is shown that when the localized spin fluctuation temperature is much larger than superconducting temperatures; (1) the transition temperature falls off rapidly with impurity concentration following a modified exponential, and (2) the thermodynamic properties (e.g., the specific heat jump at the transition and the critical field) obey the BCS law of corresponding states. A comparison is made to a recent theory by Kaiser of superconductivity in the presence of nonmagnetic resonant impurity states. Next, experiments on La and La intermetallic compounds with Ce impurities which simultaneously exhibit superconductivity and the Kondo effect are reviewed. Finally, pressure‐induced magnetic‐nonmagnetic transitions of Ce impurities in superconductors are discussed and compared with certain theoretical models.

In this paper, the authors study the quasi‐static (1 kHz) parallel reversible susceptibility (μ−1)∥ in toroǐdal samples, with respect to the grain size Dm. One can obtain a highly useful characteristic reduced curve (μ−1)∥/Dm = f (H.Dm). A concept of mechanisms of the parallel reversible susceptibility is introduced from an earlier proposed model. The values of the internal field acting on the wall, given by the analysis of (μ−1)∥, are in good agreement with those given by the analysis of the initial magnetization.

In this paper the results of numerical investigation of transverse motion influence on time duration of the ion bunch in the isochronous cyclotron are reported. The requirements to the control degree of transverse motion parameters at beam extraction from the isochronous radius and from the region with dropping magnetic field are formulated. The ion entry into the additional bunching dee operating at the highest harmonic compared with the accelerating voltage of the main dee has been investigated. In conclusion the results of numerical modelling of the beam acceleration in the ring isochronous cyclotron with double‐acceleration system at the beam extraction from radial stability boundary are given.

High speed transportation vehicles (trains) carrying superconducting magnets can be levitated by repulsion from diamagnetic currents induced in a conducting track. In a paper by Richards and Tinkham submitted to J. Appl. Phys., various approximate methods are presented for calculating the lift and drag forces for such magnetic suspensions. Fourier analysis of periodic train magnet fields is used to study “image force” and “hybrid null flux” systems which involve homogeneous conducting sheet tracks. A lumped circuit analysis is used to discuss the “null flux” principle and related systems with structured tracks. The stability and efficiency of linear induction and linear synchronous motor propulsion systems are studied using related methods.

This paper examines the effects of static magnetization dispersion in polycrystalline films on their low field, uniform mode resonance behavior. The quasistatic interaction of the disperse local magnetization with the average magnetization M⇒0, enters the description of FMR through modified initial conditions and through the internal field. The initial nonuniform state alone modifies the low field resonance behavior. In addition, quasistatic free energy minimization yields a dependence of the mean planar equilibrium angle on nonlinear interactions. This causes changes of the resonance frequency and susceptibility magnitude and, under certain conditions, the occurrence of a double resonance.

Particle accelerators have been used for some time in materials science to study the effects of irradiation damage and to implant impurity atoms to well defined concentrations. In the past the majority of this work has been of a fairly fundamental nature but recently important technological problems in connection with fast reactor development, have been highlighted. This paper will review the use of cyclotrons to study a variety of materials problems and in particular the Harwell Variable Energy Cyclotron to study the phenomenon of void formation in irradiated materials. It will illustrate how simulation experiments can help to provide an understanding of an important technological problem and furthermore provide data which can be used together with that from fast neutron irradiation to select the most suitable materials for the design of fast reactors.

This paper discusses the rationale of fast neutron therapy and presents some early results obtained at the Medical Research Council's Cyclotron Unit at Hammersmith Hospital, London. The importance of the oxygen enhancement ratio for fast neutrons is considered, together with the significance of the small proportion of anoxic cells present in most tumours. The significant features of the preliminary results obtained in patients with malignant disease are presented and the characteristics of fast neutron beams for radiotherapy are discussed.

This paper examines the dynamic effects of magnetization fluctuations in polycrystalline films on their uniform mode resonance behavior. The dynamic interactions of the non‐uniform components with the spatially averaged magnetization M⇒0 is first treated as a perturbation correction on the susceptibility χ(ω) when the interaction is small. When the interaction is large such that phenomenological damping is neglected it is shown that the fluctuations introduce regions of damped behavior. Illustrative numerical calculations are made on a model whose spatial variation is described by a single wave vector.