Who nominates judges? : Some issues underlying judicial appointments in South Africa

This article examines the importance and impact of the process of nomination on the appointment of judges in South Africa. The process of judicial appointment has changed dramatically following South Africa’s transition from apartheid to constitutional democracy. In the pre-constitutional era, appointments were made by the State President in Cabinet, with little or no external input beyond that elicited from a small political and legal elite

Resonantly driven wobbling kinks

The amplitude of oscillations of the freely wobbling kink in the $\phi^4$ theory decays due to the emission of second-harmonic radiation. We study the compensation of these radiation losses (as well as additional dissipative losses) by the resonant driving of the kink. We consider both direct and parametric driving at a range of resonance frequencies. In each case, we derive the amplitude equations which describe the evolution of the amplitude of the wobbling and the kink's velocity. These equations predict multistability and hysteretic transitions in the wobbling amplitude for each driving frequency -- the conclusion verified by numerical simulations of the full partial differential equation. We show that the strongest parametric resonance occurs when the driving frequency equals the natural wobbling frequency and not double that value. For direct driving, the strongest resonance is at half the natural frequency, but there is also a weaker resonance when the driving frequency equals the natural wobbling frequency itself. We show that this resonance is accompanied by translational motion of the kink.Comment: 19 pages in a double-column format; 8 figure

On the direct evaluation of the equilibrium distribution of clusters by simulation. II

We clarify some of the subtle issues surrounding the observational cluster method, a simulation technique for studying nucleation. The validity of the method is reaffirmed here. The condition of the compact cluster limit is quantified and its implications are elucidated in terms of the correct enumeration of configuration space

On the direct evaluation of the equilibrium distribution of clusters by simulation

An expression is derived that relates the average population of a particular type of cluster in a metastable vapor phase of volume Vtot to the probability, estimated by simulation, of finding this cluster in a system of volume V taken inside Vtot, where V<<Vtot. Correct treatment of the translational free energy of the cluster is crucial for this purpose. We show that the problem reduces to one of devising the proper boundary condition for the simulation. We then verify the result obtained previously for a low vapor density limit [J. Chem. Phys. 108, 3416 (1998)]. The difficulty implicit in our recent calculation [J. Chem. Phys. 110, 5249 (1999)], in which the approach in the former was generalized to higher vapor densities, is shown to be resolved by a method already suggested in that paper

Taking a Cultural Perspective on Intimate Partner Violence

Intimate partner violence continues to be a growing social concern associated with extensive physical, emotional, and financial consequences. Previous models of intimate partner violence have failed to recognize the role cultural components may play in the etiology of violence, specifically cultural values, the bi-dimensional process of acculturation, and sociodemographic variables. Prior research has shown these factors all contribute to women‟s perceptions of violence and such perceptions may impact the relationship between exposure and emotional outcomes. The present study examined how women‟s cultural background influences their perceptions of violence and subsequent adjustment. Eighty-six Latina women completed measures assessing cultural values, acculturation levels, attitudes regarding aggression, exposure to intimate partner violence, and psychological adjustment as well as semi-structured interviews assessing perceptions of violence in two vignettes. Analyses revealed a moderating effect of cultural values on the relationship between exposure to intimate partner aggression and perceptions of violence; however perceptions did not mediate the relation between violence exposure and subsequent adjustment. Cultural values specific to gender roles were more salient when considering perceptions of causation of violence, whereas global attitudes about aggression and dating aggression were more salient for women‟s perceptions of the acceptability and seriousness of violent behavior

Tracking interacting dust: comparison of tracking and state estimation techniques for dusty plasmas

When tracking a target particle that is interacting with nearest neighbors in a known way, positional data of the neighbors can be used to improve the state estimate. Effects of the accuracy of such positional data on the target track accuracy are investigated in this paper, in the context of dusty plasmas. In kinematic simulations, notable improvement in the target track accuracy was found when including all nearest neighbors in the state estimation filter and tracking algorithm, whereas the track accuracy was not significantly improved by higher-accuracy measurement techniques. The state estimation algorithm, involving an extended Kalman filter, was shown to either remove or significantly reduce errors due to "pixel locking". It is concluded that the significant extra complexity and computational expense to achieve these relatively small improvements are likely to be unwarranted for many situations. For the purposes of determining the precise particle locations, it is concluded that the simplified state estimation algorithm can be a viable alternative to using more computationally-intensive measurement techniques.Comment: 11 pages, 6 figures, Conference paper: Signal and Data Processing of Small Targets 2010 (SPIE

Improvement, validation, and implementation of predictive models on full scale anaerobic digestion assets

Anaerobic digestion (AD) is the most extensively used method of sewage sludge treatment in the UK, but there is a lack of practical tools available to aid operators in sewage sludge AD optimisation. This could be achieved through a modelling approach to optimise reactor loading rates, and conditions. However, current models of the AD process, such as Anaerobic Digestion Model 1 (ADM1) approach this problem by representing the fundamental biochemical and microbiology processes intrinsic to the process, which is too complex for practical application within an industrial context. A more practicable modelling system is required for industrial sewage sludge AD optimisation. Giacalone (2018) developed a sewage sludge AD model based on bench scale experimentation, to quantify the interactive effects of different major operational variables, and fundamental relationships representing first order degradation in a continuously stirred tank reactor with input variables including digester temperature, feed dry solids (DS), primary fraction, biomethane potential (BMP) and C, H and N fractions. By extensive sampling, and data cross checking, data sets were generated from 13 sewage treatment works (6 conventional and 7 advanced digestion sites), covering a wide range of digestion conditions. Key model outputs including biogas yield (BGY) and digestate ammonium-N (NH¬4-N) predictions were validated, and predictions of digestate DS were indicative of full scale performance. The ADFUN model can be adapted to represent other sludge type as predictions are based on fundamental biological and chemical sludge properties, therefore, the model was applied to estimate the BGY from AD of novel sludge types (granular and integrated fixed film sludges) in bench scale experiments with relative success. The model was also used to predict the biogas and financial benefits of digester optimisation varying scenarios. The model was effective at predicting the full-scale AD process, and applying optimised process conditions predicted by the model yields a benefit of up to 20 Nm3/tDS.Open Acces