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At present, regarding to the machining of aspheric lens mold, there are two major methods to carry out the on-machine measurement (OMM) — contacting method (CM) and non-contacting method (NCM). Here such two methods are reviewed in detail. CM is mainly based on the contacting probe which is scratching aspheric surface of lens mold to achieve profile data. To be efficient, an idea with 45° tilt of probe is proposed for OMM of lens mold by Suzuki. But generally speaking, the contacting OMM is not so efficient and can only deal with axisymmetric aspheric lens mold. On the contrary, NCM mostly uses laser to achieve aspheric profile without any contact. On ultra-precision lathe, laser scanning system or laser interferometer is mounted on the frame of lathe and transfers measurement data to machining system efficiently. However, most NCMs need stable environment and low working noise except instantaneous phase-shifting shearing interferometry (IPSSI). Therefore, a new idea about IPSSI is proposed in this paper to realize OMM of lens molds. Unfortunately, it's also difficult to test the high numerical aperture aspheric or free-form lens molds. By comparison, the newly-developed fringe reflection (FR) method is becoming the promising method because it features the high efficiency and high accuracy. However, this method has not been used for OMM system yet. Much research should be conducted for FR OMM technology.

This paper presents the fabrication, characterization, and testing of the photocatalytic potential of a non-modified titania nanotube (TNT) and Sn-modified TNT synthesized through a facile one-step hydrothermal method. Two tin compounds (SnCl2 and SnO2) and aqueous solutions (HCl and SnCl2) were utilized as precursors and acid washing solutions, respectively. Because the Sn-modified TNT was free of calcination, the resulting sample possessed a high Brunauer-Emmett-Teller surface area. In addition, the Sn-modified TNT exhibited higher electron-hole separation efficiency. The photocatalytic reaction rate for the sample with methylene blue and malachite green dye decomposition was governed on the basis of their pre-adsorption abilities. The Sn-modified TNT had more Cl species than the non-modified TNT, resulting in higher pre-adsorption abilities for the methylene blue dye. Even though the Cl species on SnO2-TNT sample surface were removed, a higher electron-hole separation efficiency and anatase-rutile mixed phase can promote the photocatalyst activity of SnO2-TNT. On the other hand, the Cl species on the surface of SnO2-TNT-HCl washing sample appeared to act as one of the adsorption sites and enhance gaseous elemental mercury removal.

The purpose of this paper is to study the consequences of the composite nature of concrete. A plausible energy balance equation is postulated and the Green-Rivlin invariance principle is applied to it to derive the linear and angular momentum balance laws. General constitutive equations are discussed with the aid of thermodynamic potentials and Coleman's method. The distribution of the applied stresses between mortar and aggregate is also studied in detail, showing for instance that substantial tensile lateral stresses may appear in mortar under uniaxial compressive loading. These results are used to derive a criterion for the onset of inelasticity in concrete.

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.

A novel uncertainty assessment methodology, based on a statistical non-parametric approach, is presented in this paper. It achieves quantification of code physical model uncertainty by making use of model performance information obtained from studies of appropriate separate-effect tests. Uncertainties are quantified in the form of estimated probability density functions (pdfs), calculated with a newly developed non-parametric estimator. The new estimator objectively predicts the probability distribution of the models error (its uncertainty) from databases reflecting the models accuracy on the basis of available experiments. The methodology is completed by applying a novel multi-dimensional clustering technique based on the comparison of model error samples with the Kruskall-Wallis test. This takes into account the fact that a models uncertainty depends on system conditions, since a best estimate code can give predictions for which the accuracy is affected by the regions of the physical space in which the experiments occur. The final result is an objective, rigorous and accurate manner of assigning uncertainty to coded models, i.e. the input information needed by code uncertainty propagation methodologies used for assessing the accuracy of best estimate codes in nuclear systems analysis. The new methodology has been applied to the quantification of the uncertainty in the RETRAN-3D void model and then used in the analysis of an independent separate-effect experiment. This has clearly demonstrated the basic feasibility of the approach, as well as its advantages in yielding narrower uncertainty bands in quantifying the codes accuracy for void fraction predictions.[All rights reserved Elsevier].

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.

Complex operations carried out in the oil and gas industry such as drilling require constant and accurate real-time monitoring of the process. To this aim, a real-time model of the drilling operation is required. Such a model is used to estimate the state of the well when and where direct and reliable measurements are not available and it helps the driller gain an overview of the drilling process. Given the harsh operating environment, sensor reliability and sensor calibration are known problem areas, and bad data quality is a common problem, affecting the accuracy of the model. As a result, the driller may be misled about the downhole situation or receive conflicting claims about operating conditions. A way to reduce uncertainty and increase confidence is to aggregate the opinion of different experts. When the expert is a computer program, such aggregation is often referred to as an ensemble approach. The principle underlies techniques that have become popular in the oil industry in recent years, such as probabilistic forecasting and ensemble Kalman filters. In this paper, we discuss this trend and develop an ensemble system for predicting the bottom-hole pressure during a managed pressure drilling operation. The improved accuracy and robustness of the ensemble approach in situations with bad data quality is demonstrated.

In this paper, the nature and location of hot carrier induced defects is studied for N-channel LDMOS (Laterally Diffused MOS) transistors. These devices are used in wireless base stations and typically operate under high drain bias of 25-30 V, making them highly susceptible to hot carrier injection. In this work, the improvement in hot carrier induced degradation by means of a dummy gate is presented. Using the charge pumping technique, it is demonstrated that, (1) significant electron trapping in the LDD region occurs for devices without a dummy gate in contrast to devices with a dummy gate. (2) For devices with a dummy gate interface traps are preferentially generated in the LDD region.

In the current decade, modeling credit risk is increasingly gaining attention by risk managers of banks and researchers. Among the available credit risk models, Merton's equity-based approach is considered as a pioneering tool for measuring default risks. From the day it was developed by Robert Merton, it is being regarded as one of the primary model of assessing credit risk. In this model the default process is endogenous, and relates to the capital structure of the firm. The model presumes that the only source of uncertainty in equity prices is the uncertainty in the firm's net asset value. Therefore, the only risk considered is the firm specific risk. Ironically, the above market condition holds only when the market is efficient. The model developed in the present paper is virtually a modification of Merton's model. However, it is not subject to the limitation of that model. Therefore, the modified model will necessarily widen the scope of equity-based modeling ranging from a strict efficient market to an inefficient market.

Aluminum/air microfluidic fuel cell (MFC) combines the advantages of co-laminar MFC and aluminum/air batteries with high energy density, low cost, membraneless and miniaturized design, which is a promising device to power the numerous nodes in the Internet of Things (IoT) ecosystems. Here, we propose a recirculating dual-electrolyte aluminum/air MFC with an alkaline anolyte and an acid catholyte. The cell exhibits an outstanding performance with an open-circuit voltage of 2.2 V and a short-current density of 1 A cm−2, benefiting from the dual-electrolyte design. In order to prevent the naturalization reaction between the electrolytes and improve the utilization rate, a regular hierarchical porous carbon paper is applied as the separator, which minimizes the mixing of electrolytes and facilitates the recirculation. This work provides an alternative route for cost-effective and high-performance aluminum/Air MFCs toward real applications.

In this paper a novel algorithm with delay guarantees for high priority traffic based on a Proportional (P) controller for Long-Reach Passive Optical Networks (LR-PONs) is proposed. We have recently demonstrated that Proportional-Integral-Derivative (PID) controllers are quite effective when controlling guaranteed bandwidth levels and in this paper this functionality is adapted to jointly deal with Class of Service (CoS) and client differentiation in order to fulfill delay requirements. Therefore, it leads to an efficient control of the mean packet delay which enhances the provided Quality of Service (QoS) inside the LR-PON. Simulation results have exhibited that the bandwidth allocation process made by the P controller achieves this objective faster than other existing proposals. In fact, it stabilizes the priority delays in less than 2min comparing with 5 or 6min obtained by other proposals. Furthermore, it has been demonstrated that its performance is more robust than other proposals since it is independent of the initial network conditions, adapting very efficiently the available resources in order to comply with the established delay bounds of the most restrictive services.

This paper reports on the catalytic performance and deactivation in aqueous phase reforming of wastewater streams for H2 production. Brewery wastewater was chosen as representative of this type of effluent. The effect of catalyst support textural characteristics was evaluated using an activated carbon and different modified supports obtained by infiltration and carbonization of a phenolic resol resin into activated carbon. The effect of active phase was evaluated using Pt and PtRe catalysts with different metal molar ratio. At short time on stream values, Pt catalysts supported on modified activated carbon showed higher H2 production than those supported on unmodified activated carbon, indicating that a lower microporosity facilitates the transport of reactants to catalytic active sites and release of reaction products. Bimetallic PtRe catalysts showed higher activity than Pt, particularly using a metal molar ratio of 1:1, which yielded the highest H2 production (117.2 μmol min−1). Despite the different catalysts tested, early and significant deactivation was observed. The characterization of used catalysts allows postulating the adsorption of organic species and/or coke-like matter deposition on the catalysts surface as main causes of deactivation.

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.

Economic theorizations of political bias and war as laid out in Bargaining Theory (Jackson and Morelli 2007; Anderton and Carter 2009) have demonstrated that a political leadership’s penchant for war may be much higher than that of the people they represent, and the calculus of war for internal political gains can spur them on to inter-state violence. To put this assertion to the test, this working paper examines the BJP under Narendra Modi as instigator of the Pulwama War and the India-Pakistan standoff of 2019. The findings of the working paper indicate that the BJP government’s expediency of war conforms to, and resonates with, the bargaining theory of political bias and war, as theorized in the game-theoretic economic literature.

The combination of Java applications as graphical user interfaces and the Matlab-Simulink environment as the simulation engine seems to be a good solution for taking a particular control lab to distant students. In this paper, it is presented a new kind of simulation environment for qualitative teaching on concepts of Control Engineering by means of a suitable configuration of experiments by the tutor or teacher.

Due to severe droughts and rapid urbanization, Cape Town municipality including small towns along the West Coast of South Africa are facing water shortages. Managed aquifer recharge (MAR) seems to offer a solution to improve water security in this drought-prone area. This paper presents a conceptual framework within which numerical modelling of the aquifers system is operated to improve water security of West Coast. The ModelMuse software that included MODFLOW and MODPATH packages was used. Scenarios which considered recharge aspects were used to evaluate suitable sites and appropriate scheme of implementing MAR. The result showed that it is feasible to implement MAR in the upper unconfined aquifer unit (UAU) which had estimated available space for MAR of 915.7 million m3. For the semi-confined lower aquifer unit (LAU), the clay-missing window area located at west of Hopefield was a suitable site to implement MAR. However, the prevailing little space in LAU to store recharged water was a limiting factor to support the implementation of MAR scheme. Details on the possibility of implementing MAR scheme for West Coast aquifers system were discussed based of the simulations that were carried out. Although the modelling approach does not provide precise areas but a management tool, it provides key insights that are applicable in aquifer systems of similar characteristics.

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 paper deals with the existence of nonnegative solutions for ( p , N ) systems in R N involving critical exponential growth nonlinearities. The constructed solution has both components nontrivial and different, that is it solves the actual system, which does not reduce into an equation. The main feature and novelty of the paper is the presence of a general coupled critical exponential term of the Trudinger–Moser type, set in R N .

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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This paper is an attempt to understand the preferential treatment granted to Hindus under the Income Tax Act, 1961. The pertinent question involved is whether preferential treatment granted to Hindu under Income Tax Law is justifiable. Hindu Law defines HUF as a family comprising males lineally descended from a common ancestor and includes their wives and daughters. It is an independent taxable entity under the Tax Law and assessed to tax separately as a distinct legal person. Moreover, References of Sec. 80C, 80D, 80G, 80L, 54 of ITA, 1961 are advanced to elucidate HUF as tax saving opportunity granted to Hindu in the form of HUF concept. Deduction and exemption of tax under the act is repeatedly witnessing malpractice under the sheath of “Tax Benefit of Hindu Undivided Family”. The area of concern involved is whether such deduction or exemption would amount to colourable tax evasion in certain cases. Tax Planning under HUF is legitimate and within the framework of law. However, it cannot be denied that use of tax planning in existing sense is colourable and also encourages avoidance of payment of tax as laid down in catena of judgments.

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