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After outlining the basic principles of superconductivity and the history of its development, this paper describes some of the potential applications of the technology, particularly for the electricity supply industry. It charts the development of the use of superconductors in energy research from the mid-1960s on, reviewing the projects developed over that period, and considers why the impetus behind such projects dissipated in the 1980s. The events of the last 18 months — since the discovery of high temperature superconducting materials — and the subsequent explosion of interest in the new materials are then examined. Of particular interest here is the contrast between the emergence of a powerful coalition of government, industry and science in a number of countries anxious to obtain maximum advantage from the technology and the reaction of the energy research community. The paper concludes by identifying the problems of the new materials and of superconductivity itself for the ESI, suggesting how they might interact in the future, and considers how these developments illustrate the relationship between the innovation process and technology choice in the energy sector.

In this paper, we characterize the class of all spaces X whose products with a fixed non-Archimedan space Y are normal. In particular, we give a characterization of all spaces X whose products with every ω μ -metrizable space are normal.

The paper presents a data reduction method for determination of thermal diffusivity in flash method. It is based on non-linear χ 2 fit to a model which takes into consideration heat losses. The advantage of the method is that it does not need a knowledge of base line and is suitable for data disturbed by noise and mains hum. A comparison with some other data reduction methods is given.

On what grounds does the law punish attempted offenses? The dominant answer is that the law punishes attempts to commit an offense precisely because they are attempts (extra-legally), and it is true as a general moral principle that if one should not X, one should not attempt to X. If this is right, then the proper contours of the law of attempts should track the contours of what are attempts (extra-legally). At least to a first approximation, that is, law should track metaphysics. Call this the “Attempt Theory” of attempt liability. Gideon Yaffe’s recent book, "Attempts," is a rigorous and philosophically sophisticated critical analysis of attempt law predicated on just this foundational assumption — the assumption, to repeat, that attempts to commit an offense should be criminalized because they are attempts as a pre-legal or extra-legal matter. However, there is another possible answer to the question. Possibly, those things that are in fact attempts are properly criminalized not because they are attempts, but because the best reasons for criminalizing the complete or “perfect” offense are also good reasons to criminalize this conduct, and there are no compelling reasons, of policy or justice, not to. We can call this the “Underlying Reasons Theory” of attempt liability. The Underlying Reasons Theory does recognize that there are things in the world that are attempts and that one who attempts to do what the criminal law forbids should be punished. It just maintains that the fact that an actor attempted to commit an offense is not, strictly speaking, what justifies our punishing her. This short review of Yaffe’s book explicates the difference between the Attempt Theory and the Underlying Reasons Theory as approaches to criminal liability for what we presently call “attempts.” In a nutshell: paradigmatic attempts would be criminalized on both accounts, but the Underlying Reasons Theory is likely to endorse criminalization of some conduct that the Attempts Theory would not. This paper advocates the Underlying Reasons Theory and argues that we can and should assess the proper scope of “attempt law” without working through the metaphysics of attempts.

Numerical simulation by the finite-element method is one of the most powerful means for simulating sheet forming processes, including the possibility to predict the development of defects such as wrinkling. In this paper, numerical simulations of the integral hydroforming of shell products, the hydroforming process of tubular products and the viscous pressure forming of a superalloy corrugated part are reported. The simulations were conducted using the explicit finite-element code LS-DYNA and the code DEFORM.

The main chemical constituents of the genus Polygonum (Polygonaceae) are flavonoids, quinones, phenylpropanoids, and terpenoids, which show anticancer, antitumor, anti-oxidative, anti-inflammatory, analgesic, antibacterial, insecticidal, and other pharmacological effects. This paper summarizes research on the chemical constituents and pharmacological effects of compounds from the genus Polygonum in last 15 years. Keywords: Polygonum, Chemical constituents, Bioactivity, Flavonoid, Anticancer

The paper presents a novel data-driven method for fault detection and isolation of control moment gyroscopes onboard satellites. The proposed method uses the Chebyshev Neural Network and genetic algorithm in conjunction with satellite attitude rate data only. A data-driven model is first developed that fuses the symmetric property of the data and the system orientation property of actuators that reduces the need for historical data by 93.75%. Next, the data is trained using Chebyshev Neural Network. An adaptive threshold-based fault detection algorithm is applied to detect the faults in the spin and gimbal motors of the control moment gyroscopes. A fault isolation scheme is developed wherein an objective function is optimized using a genetic algorithm for different cases of system parameters. The proposed scheme has a success rate of 93.5% in isolating faults of 8 motors (4 gimbal and 4 spin) that can fail in 254 different ways. Overall, the proposed methodology can be regarded as a promising fault diagnostic tool for satellites using limited historical data and measurements.

The aim of this paper is to present an analytical study for the investigation of the reciprocal metamaterial gyro-bianisotropy effects on the input impedance of a dipole antenna. This study is based on the numerical resolution, using the spectral method of moments (SMoM), of the integral equation developed through the mathematical derivation of the appropriate spectral Green’s functions of the studied dipole configuration. The original obtained results are discussed and showed good agreements with the isotropic studied cases available in published literature. It is found that the imaginary valued magnetoelectric elements (chiral medium) exhibit an inverse effect on the resonant length compared to purely real elements (Tellegen medium), while negative elements decrease the input impedance. Combination of the two cases has led to more general complex media with further inspiring features.

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