Variation without consideration Dawson, Francis
New Zealand universities law review,
12/2021, Letnik:
29, Številka:
4
Journal Article
Recenzirano
This article reviews a decision of the High Court not to follow the dictum of the Court of Appeal in 'Antons Trawling Co Ltd v Smith' that no consideration is required to support a contractual ...variation if the agreement is acted upon and is not the product of illegitimate pressure. In what follows it is argued that the Judge was correct not to do so. Every variation has the effect of discharging the original contractual obligation and substituting it with a revised obligation. How is the release of the original obligation effected? Accrued obligations are guarded jealously by the common law and generally speaking are not released except for valuable consideration or under deed. The promisee does not discharge an accrued obligation by simply renouncing it. Existing authority distinguishes between the variation (and discharge) of obligations occurring under deeds and those occurring under simple contracts, and also between variations and discharges occurring before breach and those occurring after breach. None of the relevant cases appear to have been cited to the Court of Appeal in 'Antons Trawling' and the dictum contradicts a mass of established authority on the discharge of existing obligations occurring on a variation.
This article examines the scope of the doctrine of part performance. It asks whether the doctrine is to be explained as a separate and technical head of equity which requires, in order to maintain ...consistency with the policy behind the 'Statute of Frauds', that the acts of part performance relied upon by a plaintiff evidence the existence of a contract for the sale of land. Must the acts relied upon be acts in the performance of the contract which unequivocally refer to some such agreement as that alleged? Or should the doctrine rather be viewed as precluding a defendant acting unconscientiously by sheltering behind the 'Statute of Frauds' after having induced the plaintiff to carry out the acts of part performance relied upon by the plaintiff? This article has been prompted by the reasoning to be found in a recent High Court of Australia decision endorsing the first approach, which views the doctrine as a separate and technical head of equity and rejecting much of the reasoning in an earlier House of Lords decision, which had rejected that approach as being inconsistent with the underlying nature of the part performance doctrine.
This article presents an integrated magnetics (IM) structure that functions as a current-doubler rectifier (CDR). The proposed IM-CDR is suitable for electrochemical wastewater treatment applications ...where low-voltage high-current power converters are required for effective treatment. Electrochemical wastewater treatment is a promising technology that has several advantages compared to the traditional biological methods currently employed in the mining industry. However, the technology suffers from high operating cost due to the conduction losses associated with long cables or busbars that run from the source to the treatment cell carrying high current. The IM approach integrates the transformer and two filtering inductors of the discrete CDR (D-CDR) into one magnetic structure which allows for the secondary side of the structure to be packaged with the electrochemical cell, thus resulting in a HVdc distribution network, and as a result, lowers the conduction losses while still benefiting from the ripple cancellation offered by the CDR architecture. This article presents a design example to help the designer relate the required electrical characteristics of the D-CDR to the design parameters of the IM-CDR. A finite element analysis simulation is performed on the IM structure to validate the derived electrical equivalent model. The IM structure is also experimentally built in our lab, achieving a 97.8% efficiency over a 20-40 A load range.
This paper proposes a new method to optimize the rotor structure in PM synchronous motors. The optimization process combines the topology optimization method and a constraint related to the shape of ...PMs, which accounts for manufacturing limitations. The rotor structures are designed considering two kinds of stator windings and two types of current driving methods. The obtained rotor structures are initially assumed to consist of four hexahedron PMs. The final shapes are obtained by a full search method.
Ammonia is a common contaminant in municipalities where human waste causes nitrification of local water bodies. In mining, ammonia contamination occurs as a byproduct of biological water treatment, ...from the use of ammonium nitrate fuel oil in explosives, and from the exposure of ammonia rich soils during the excavation process. In particular, gold mine effluent represents a significant source of ammonia and nitrogen-based contaminants. Current biological and abiotic treatment processes are difficult to employ at the scale required at mine sites due to the high operating costs, or are limited in effectiveness due to a lack of natural resources required to facilitate the treatment. This article evaluates the use of electrooxidation as a cost effective alternative to treating ammonia-laden wastewater in mining applications. Two mixed metal oxide electrodes are assessed in this article: IrO<inline-formula><tex-math notation="LaTeX">_{2}</tex-math></inline-formula>/Ti and RuO<inline-formula><tex-math notation="LaTeX">_{2}</tex-math></inline-formula>/Ti anodes. A Monte Carlo simulation is performed to determine a probabilistic range of capital and operating expenditure for a mining operation deploying an electrooxidation wastewater treatment system. The lowest capital cost of operating the electrochemical treatment occurs at a current density of 200 A/m<inline-formula><tex-math notation="LaTeX">^{2}</tex-math></inline-formula>, where the number of cells required for treatment is minimized.
This paper presents a new hybrid passive power device, denoted as the hybrid transformer, which is an improved alternative to the classical two-winding high-frequency transformer (100's kHz-MHz). The ...hybrid transformer is comprised of a coupled inductor topology, that provides load-source matching, denoted as the mutual branch topology, and a dielectric isolation device denoted as the multilayer capacitive isolation device. The main focus of this paper is on the design and operation of the mutual branch topology. Simulation results are shown to highlight the improved efficiency of the hybrid transformer over a conventional high-frequency transformer. Finally, the efficiency of the hybrid transformer is compared with that of a classical two-winding transformer using the same resonant converter, highlighting the improved efficiency of the hybrid transformer (up to 10% improved efficiency for light loads).
This paper describes a modeling approach for a vortex water-wall argon arc lamp that is amenable to implementation in real-time controller hardware. The net emission coefficient (NEC) method has been ...successfully applied for different current levels and can predict the electrical properties of the positive column to sufficient accuracy. The radiation efficiency as a function of the isothermal core temperature has been explained qualitatively, but the correction for radiation efficiency as a function of input power has been implemented as a lookup table using experimental data.
Control of Wafer Temperature Using a Vortex Water-Wall Argon Arc Grover, Harpreet Singh; Dawson, Francis P.; Camm, Dave M. ...
IEEE transactions on industry applications,
2015-Nov.-Dec., 2015-11-00, 20151101, 2015-11, Letnik:
51, Številka:
6
Journal Article
Recenzirano
This paper describes a constant switching frequency variable duty cycle control strategy that adjusts the current in a vortex water-wall argon arc lamp to achieve wafer temperature tracking in ...response to a temperature ramp request. The control system includes a model for the following: 1) the outer loop temperature controller; 2) the inner loop current controller; 3) the wafer temperature; and 4) the irradiation produced by the arc lamp in response to arc current changes. The controller design is able to provide a well-behaved arc current and good temperature tracking performance that accommodates for no temperature feedback below 300 °C and a bumpless transfer once temperature feedback is available.
This paper describes the application of a vortex water wall high-pressure argon lamp for a semiconductor annealing process. These lamps have been designed to operate up to a 500-kW power level, have ...a continuous spectrum, similar to daylight, and have been used to characterize solar cells. Precise control of the radiated power generated by the lamps is required, which, in turn, requires an accurate electrothermooptical dynamic model of the lamp and an optothermal model of the wafer. This paper discusses general aspects regarding the modeling of the system consisted of the lamp and the wafer. The main contributions of the paper are the following: (1) a simplified means of relating the radiation exiting the lamp to the electrical power injected into the lamp, taking into account radiation from an isothermal core and absorption in the cold swirling argon gas, the water wall, and the quartz envelope; and (2) a model to describe energy exchange between the lamp and the wafer and experimental results to indicate the good agreement between the model and the actual apparatus. Two companion papers discuss the details of the arc model and the discrete-time control algorithms developed to model the wafer subsystem and the arc subsystem.
This paper presents a new design for an integrated, multilayer dielectric ceramic device that is suitable for isolated high frequency (>100 kHz) power transfer. The multilayer capacitive isolation ...device (MLCID) is a four terminal multilayer ceramic structure consisting of barium strontium titanate and alumina layers. Some key advantages of the MLCID are a reduction in the losses achieved in comparison with conventional decoupling techniques and the ease of manufacturing due to the planar design. The paper focuses on the MLCID design details, its characterization, and its performance.
