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1 – 10 of over 3000This study seeks to explain how a cybernetic system, the human brain, creates the cognitive models that are applied by physics to explain particular phenomena of the physical…
Abstract
Purpose
This study seeks to explain how a cybernetic system, the human brain, creates the cognitive models that are applied by physics to explain particular phenomena of the physical world, namely, the electrostatic force and the annihilation of matter and antimatter.
Design/methodology/approach
This study applies findings in cognitive psychology of vision, neuropsychology of the hemispheric mechanisms and quantum mechanics in order to explain how the electrostatic force operates at distance between two charged particles.
Findings
In addition to the quantum fields theory, which explains the electrostatic force by photons that carry this force between charged particles (and is related to the left‐hemispheric cognitive mechanism) a dual theory is suggested that explains this force by interchanging of features between particles (and is related to the right‐hemispheric cognitive mechanism).
Originality/value
Like Fidelman's previous studies, this too demonstrates that cybernetic considerations which use cognitive psychological, neuropsychological and physical‐knowledge can obtain testable and applicable physical theories.
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Wojciech Konior, Romana Ratkiewicz and Jan Kotlarz
This paper aims to review the current knowledge about the neutral component of the local interstellar medium (LISM), which due to the resonant charge exchange, photoionization and…
Abstract
Purpose
This paper aims to review the current knowledge about the neutral component of the local interstellar medium (LISM), which due to the resonant charge exchange, photoionization and electron impact ionization processes has a profound impact on the heliosphere structure.
Design/methodology/approach
This work is based on the heliospheric literature review.
Findings
The summary of four major effects of neutral hydrogen atoms penetrating solar wind (SW), i.e. the disappearance of the complicated flow structure; the emergence of “hydrogen wall” in front of the heliopause (HP); decreasing distance of termination shock (TS), HP and bow shock (BS) layer from the Sun; and recently discovered by the Interstellar Boundary Explorer mission, a region of enhanced energetic neutral atom (ENA) emission seen in all sky maps as a ribbon.
Practical implications
In the context of constantly developing space technologies in aerospace engineering and prospective deep space missions, there is a need of general reviews about the interstellar space surroundings of the Sun and gathering the knowledge to help in theoretical, numerical and experimental investigations such as the optimization of the scientific equipment and spacecraft structure to work in specific conditions.
Originality/value
The survey encapsulate basic and relevant processes playing an important role in the physics of the nearest surroundings of the Sun and the latest results of numerical and experimental investigations focused on the neutral LISM component and its influence on the heliosphere, which is strongly desired in future works. Until now, not many of such reviews have been done.
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Ming‐Cheng Cheng and E.E. Kunhardt
A non‐equilibrium multi‐valley transport model for carriers in compound semiconductor devices has been developed. This macroscopic transport model provides an efficient scheme for…
Abstract
A non‐equilibrium multi‐valley transport model for carriers in compound semiconductor devices has been developed. This macroscopic transport model provides an efficient scheme for device modeling, and can overcome the difficulty in evaluating the relaxation times in multi‐valley conservation equations without a priori assumption of the displaced‐Maxwellian distribution. This model has been successfully applied to electron transport in GaAs subjected to rapidly time‐varying fields. The results have suggested that the macroscopic effective mass of electrons might be strongly dependent on average velocity.
The purpose of this paper is to introduce new non‐classical implementations of neural networks (NNs). The developed implementations are performed in the quantum, nano, and optical…
Abstract
Purpose
The purpose of this paper is to introduce new non‐classical implementations of neural networks (NNs). The developed implementations are performed in the quantum, nano, and optical domains to perform the required neural computing. The various implementations of the new NNs utilizing the introduced architectures are presented, and their extensions for the utilization in the non‐classical neural‐systolic networks are also introduced.
Design/methodology/approach
The introduced neural circuits utilize recent findings in the quantum, nano, and optical fields to implement the functionality of the basic NN. This includes the techniques of many‐valued quantum computing (MVQC), carbon nanotubes (CNT), and linear optics. The extensions of implementations to non‐classical neural‐systolic networks using the introduced neural‐systolic architectures are also presented.
Findings
Novel NN implementations are introduced in this paper. NN implementation using the general scheme of MVQC is presented. The proposed method uses the many‐valued quantum orthonormal computational basis states to implement such computations. Physical implementation of quantum computing (QC) is performed by controlling the potential to yield specific wavefunction as a result of solving the Schrödinger equation that governs the dynamics in the quantum domain. The CNT‐based implementation of logic NNs is also introduced. New implementations of logic NNs are also introduced that utilize new linear optical circuits which use coherent light beams to perform the functionality of the basic logic multiplexer by utilizing the properties of frequency, polarization, and incident angle. The implementations of non‐classical neural‐systolic networks using the introduced quantum, nano, and optical neural architectures are also presented.
Originality/value
The introduced NN implementations form new important directions in the NN realizations using the newly emerging technologies. Since the new quantum and optical implementations have the advantages of very high‐speed and low‐power consumption, and the nano implementation exists in very compact space where CNT‐based field effect transistor switches reliably using much less power than a silicon‐based device, the introduced implementations for non‐classical neural computation are new and interesting for the design in future technologies that require the optimal design specifications of super‐high speed, minimum power consumption, and minimum size, such as in low‐power control of autonomous robots, adiabatic low‐power very‐large‐scale integration circuit design for signal processing applications, QC, and nanotechnology.
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Hamed Al-sorory, Mohammed S. Gumaan and Rizk Mostafa Shalaby
This paper aims to summarise the effects of ZnO nanoparticles (0.1, 0.3, 0.5, 0.7 and 1.0 Wt.%) on the structure, mechanical, electrical and thermal stability of Sn–3.5Ag–0.5Cu…
Abstract
Purpose
This paper aims to summarise the effects of ZnO nanoparticles (0.1, 0.3, 0.5, 0.7 and 1.0 Wt.%) on the structure, mechanical, electrical and thermal stability of Sn–3.5Ag–0.5Cu (SAC355) solder alloys for high-performance applications.
Design/methodology/approach
The phase identification and morphology of the solders were studied using X-ray diffraction and scanning electron microscopy. Thermal parameters were investigated using differential scanning calorimetry. The elastic parameters such as Young's modulus (E) and internal friction (Q−1) were investigated using the dynamic resonance technique, whereas the Vickers hardness (Hv) and creep indentation (n) were examined using a Vickers microhardness tester.
Findings
Microstructural analysis revealed that ZnO nanoparticles (NPs) were distributed uniformly throughout the Sn matrix. Furthermore, addition of 0.1, 0.3 and 0.7 Wt.% of ZnO NPs to the eutectic (SAC355) prevented crystallite size reduction, which increased the strength of the solder alloy. Mechanical parameters such as Young's modulus improved significantly at 0.1, 0.3 and 0.7 Wt.% ZnO NP contents compared to the ZnO-free alloy. This variation can be understood by considering the plastic deformation. The Vickers hardness value (Hv) increased to its maximum as the ZnO NP content increased to 0.5. A stress exponent value (n) of approximately two in most composite solder alloys suggested that grain boundary sliding was the dominant mechanism in this system. The electrical resistance (ρ) increased its maximum value at 0.5 Wt.% ZnO NPs content. The addition of ZnO NPs to plain (SAC355) solder alloys increased the melting temperature (Tm) by a few degrees.
Originality/value
Development of eutectic (SAC355) lead-free solder doped with ZnO NPs use for electronic packaging.
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A transport model has been developed which is reasonably accurate, and has proven quite efficient for the two‐dimensional numerical simulation of submicron‐scale Si and GaAs…
Abstract
A transport model has been developed which is reasonably accurate, and has proven quite efficient for the two‐dimensional numerical simulation of submicron‐scale Si and GaAs devices. In this model an approximate form of the energy‐transport equation is developed; this equation is easily included in otherwise‐conventional device simulation codes, which then require only slightly more solution time than standard models using field‐dependent transport coefficients. Calculations for 0.25 micron gate length Si and GaAs MESFET's show that velocity overshoot effects can be very important, particularly in the latter material; predicted saturation currents in the GaAs devices are almost three times larger than those that would have been predicted using conventional transport models. The model described, and its application in simulation programs, should find use in the design of submicron‐scale devices to properly take advantage of overshoot phenomena.
The need for change in the management and administration of libraries is now well recognized. Current thought seems to be largely devoted to systems analysis and streamlining of…
Abstract
The need for change in the management and administration of libraries is now well recognized. Current thought seems to be largely devoted to systems analysis and streamlining of traditional library functions. Foskett, however, puts forward a view that libraries ‘are not closed and static systems, but must continually develop in relation to their environment, must be prepared to change the organization of their various parts in order to survive and fulfil the purpose for which they were created’. We endorse this view whilst stressing the need for the research library to be willing to expand its function to that of a system of communication as well as information. In fields of pure research which depend upon the rapid exchange of current knowledge it is necessary for an equal emphasis to be placed on both inward and outward communication. Providing the most useful service to scientific users within the confines of a stated number of staff and a restricted amount of money leads to a necessity for versatility in the staffing of such services.
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This paper aims to address challenges in strategic management and tries to find ways to make a breakthrough. Strategic management theorists and practitioners need new scientific…
Abstract
Purpose
This paper aims to address challenges in strategic management and tries to find ways to make a breakthrough. Strategic management theorists and practitioners need new scientific theories. In the modern turbulent environment, the extant strategic management research (SMR) and strategic management theories can neither satisfy the practical needs nor the theoretical developmental needs of strategic management.
Design/methodology/approach
The paper uses critique viewpoints that are unfolded according to the logic of how theories will satisfy the practical and theoretical needs. Physics and mathematics are regarded as the most beautiful and perfect scientific research fields, which help predict physical phenomena such as solar eclipse precisely. Therefore, the paper uses physics and mathematics as benchmarks to explore how SMR should make efforts to push the research further.
Findings
The paper provides a different viewpoint that will help strategic theorists and practitioners investigate and understand strategic phenomena more holistically. SMR should contribute to strategic theoretical and practical progress and not just to the game of academic game play. For the goal, the paper summarizes and refines the definition of strategic management in an alternative but practical and innovative perspective, and then delineates the criteria for SMR topic choice; identifies the dilemmas and challenges the SMR faces; and points out the new approaches the strategic management researchers should explore.
Originality/value
The paper challenges the mainstream of SMR by identifying the shortcomings, dilemmas, and challenges of the current SMR, and then highlights new ways to make breakthrough in SMR. The study will make strategic management scholars rethink their research and do meaningful research from the perspectives of theoretical contribution and practical guidance.
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Giovanni Mascali and Vittorio Romano
On the basis of the maximum entropy principle, seeks to formulate a hydrodynamical model for electron transport in GaAs semiconductors, which is free of any fitting parameter.
Abstract
Purpose
On the basis of the maximum entropy principle, seeks to formulate a hydrodynamical model for electron transport in GaAs semiconductors, which is free of any fitting parameter.
Design/methodology/approach
The model considers the conduction band to be described by the Kane dispersion relation and includes both Γ and L valleys. Takes into account electron‐non‐polar optical phonon, electron‐polar optical phonon and electro‐acoustic phonon scattering.
Findings
The set of balance equation of the model forms a quasilinear hyperbolic system and for its numerical integration a recent high‐order shock‐capturing central differencing scheme has been employed.
Originality/value
Presents the results of simulations of n+ ‐n‐n+ GaAs diode and Gunn oscillator.
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