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This paper uses the gravity model to examine the impact of the Common Market for Eastern and Southern Africa on the flow of Kenya's exports. The empirical results suggest that COMESA has the effect of trade creation. No evidence for trade diversion is found. Accordingly, COMESA has helped to improve Kenya's export performance and, in turn, assisted in the effort to achieve the Millennium Development Goals. The results also show that nominal GDP of importing countries, distance, adjacency, and common official language have a statistically significant impact on the flow of Kenya's exports.

Industries, especially power plants, using steam as power fluid employ many equipment and systems using saturated steam. Mathematical modeling of this saturated steam water space (SSWS) equipment is important for simulators catering to these industries and power plants. Single-equation-based modeling approach and its optimized version, mass factor–volume factor approach, are very efficient in modeling SSWS with bounded volumes, where the volume of the space is fixed. In unbounded volumes, the volume may be changing or is unbounded because of expansion, contraction or pressure control. The purpose of this paper is to propose a single equation based modeling approach for unbounded SSWS. Such unbounded volumes are encountered in coolant channels of pressurized heavy water reactor (PHWR)-type nuclear power plants (NPPs).

This paper proposes an extension of a single-equation approach by considering a subsection of the volume as miniature Point SSWS. In the proposed Point SSWS, the total heat, mass and volume of the SSWS are delinked and overall density and heat density are introduced in place. With this extension, Point SSWS can be applied to unbounded volumes.

In this study, 392 coolant channels of proposed 680 MWe PHWR have been simulated to ascertain the overall coolant density when coolant boils partially on nuclear heating. The simulation results have been compared with simulation results available from previous researchers and it has been found that the values are in line with previous researchers with maximum deviation of 1.2 per cent.

From the simulation results and their low value of deviation, it is clear that point space approach can be effectively used in modeling Point SSWS. Moreover, theoretically, it has been proved that the density of homogenous steam–water mixture is dependent only on the bulk heat density and temperature of the mixture.

Obesity among elderly consumers precipitates undesirable health outcomes. This study aims to investigate the effects of environmental cues on food intake of elderly consumers in an aged-care facility.

A longitudinal study conducted over 17 weeks in situ within an aged-care facility with 31 residents investigated how auditory (soothing music), olfactory (floral-scented candle) and visual (infographic on health benefits of the main meal component) cues influenced food intake quantity during a meal, while accounting for portion size effect (PSE).

Analysing the cross-sectional results of individual treatments and rounds did not reveal any consistent patterns in the influence of the three environmental cues. Longitudinal analyses, however, showed that the presence of auditory and olfactory cues significantly increased food intake, but the visual cue did not. Moreover, PSE was strong.

Extending research into environmental factors from a commercial to a health-care setting, this study demonstrates how the presence of auditory and olfactory, but not cognitive cues, increased food intake behaviour among elderly consumers. It also shows that a cross-sectional approach to such studies would have yielded inconclusive or even misleading findings. Merely serving more would also lead to higher food intake amount.

Environmental factors should be a part of health-care providers’ arsenal to manage obesity. They are practical and relatively inexpensive to implement across different health-care settings. However, the same environmental factors would have opposite desired-effects with normal or underweight residents, and hence, aged-care facilities need to separate the dining experience (or mealtime) of obese and other residents. Quantity served should also be moderated to discourage overeating.

While studies into managing obesity, particularly among older adults, have mainly focused on techniques such as pharmacotherapy treatments with drugs, dietary management or even lifestyle change, less attention has been given to the influence of environmental cues. This study, executed in situ within an aged-care facility, provided evidence of the importance of considering the impact of environmental factors on food intake to help reduce obesity.

The purpose of this study was to establish an objective mathematical decision-making procedure to help universities prioritize credits, while using the Sustainability Tracking, Assessment and Rating System (STARS) framework developed by the Association for Advancement of Sustainability in Higher Education (AASHE), when pursuing their sustainability goals in the short-, medium- and long-term. The authors used the assessment data from Dominican University of California (DUofC), as our case study.

Two criteria, the number of possible points available and overall priority, were developed to classify credits in the STARS version 1.2 framework into six groups from lowest to highest level of difficulty. Two mathematical credit-selecting models based on how many points were available per credit, partial or full amount, were also established to produce short-, medium- and long-term plans.

Our results show that DUofC can reach the Silver level in three years by working on 25 credits; Gold level in nine years by focusing its efforts in 28 additional credits; and Platinum level in 15 years by improving another 10 credits.

The procedure developed in this study can be applied to other universities and other versions of the STARS framework.

The purpose of this paper is to demonstrate that using advanced powertrain technologies can help outperform the state of the art in F1 and LeMans motor racing. By a careful choice and sizing of powertrain components coupled with an optimal energy management strategy, the conflicting requirements of high-performance and high-energy savings can be achieved.

Five main steps were performed. First, definition of requirements: basic performance requirements were defined based on research on the capabilities of Formula 1 race cars. Second, drive cycle generation: a drive cycle was created using these performance requirements as well as other necessary inputs such as the track layout of Circuit de la Sarthe, the drag coefficient, the tire specifications, and the mass of the vehicle. Third, selection of technology: the drive cycle was used to model the power requirements from the powertrain components of the series-hybrid topology. Fourth, lap time sensitivity analysis: the impact of certain design decisions on lap time was determined by the lap time sensitivity analysis. Fifth, modeling and optimization: the design involved building the optimal energy management strategy and comparing the performance of different powertrain component sizings.

Five different powertrain configurations were presented, and several tradeoffs between lap time and different parameters were discussed. The results showed that the fastest achievable lap time using the proposed configurations was 3 min 9 s. It was concluded that several car and component parameters have to be improved to decrease this lap time to the required 2 min 45 s, which is required to outperform F1 on LeMans.

This research shows the capabilities of advanced hybrid powertrain components and energy management strategies in motorsports, both in terms of performance and energy savings. The important factors affecting the performance of such a hybrid race car have been highlighted.

This study aims to prevent mild steel (MS) against corrosion in 0.5 M HCl solution, 2-amino-4-methoxy-6-methyl-1,3,5-triazine was used. The effectiveness of the compound as a corrosion inhibitor was studied via electrochemical, surface and theoretical calculation techniques.

For concentrations ranging from 0.5 to 10.0 mM, almost similar polarization resistances were obtained from electrochemical impedance spectroscopy (EIS) and linear polarization resistance tests. It also investigated inhibitive activity of 2-amino-4-methoxy-6-methyl-1,3,5-triazine on the steel surface using scanning electron and atomic force microscope instruments. Langmuir adsorption is the best matched isotherm for the adsorption of the inhibitor to the steel surface.

EIS method was used to determine inhibition efficiency, which was determined to be 95.7% for 10.0 mM inhibitor containing acid solution. Density functional theory’s predictions for quantum chemistry agreed well with the other experimental results.

The methods used in this study are effective and applicable; the used organic inhibitor is 2-amino-4-methoxy-6-methyl-1,3,5-triazine; and protective effectiveness is important, which is crucial for the task of MS corrosion prevention.

Outlines previous research on the capital asset pricing model and its extensions; and fluctuations in the Greek economy and capital market between 1980 and 1992. Develops a mathematical, multi‐factor, risk‐return model and applies it to Greek data for this period, split into two sub‐periods: 1980‐1986 and 1986‐1992. Identifies and discusses the m ost important macrovariables influencing security returns for both periods. Concludes that the model does capture the features of a changing economic environment and links risk premia to macroeconomic factors, although it lacks intertemporal stability.

We survey the literature on the Risk Augmented Mincer equation that seeks to estimate the compensation for uncertainty in the future wage to be earned after completing an education. There is wide empirical support for the predicted positive effect of wage variance and the negative effect of wage skew. We discuss robustness of the findings across specifications, potential bias from unobserved heterogeneity and selectivity and consider the core issue of students' information on benefits from education.