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The purpose of this study is to examine households’ behavior towards dirty cooking energy utilisation in an environment where relatively higher accessibility to clean energy is noted. Although the low utilisation rate of clean energy can partly be attributed to utility gains anticipated in dirty energy mixes (DEMs) arising out of accessibility constraints, affordances and enablers, it is still unclear on the extend at which each of these contributes towards DEMs manifestation among the seemingly well-to-do households with higher levels of clean energy mixes (CEM) access. This study, therefore, hinges on scrutinising on this lower utilisation patterns despite a seemingly higher accessibility of CEMs, specifically liquified petroleum gases (LPG).

The study is based on a household’s survey that was carried out in 2018, reaching a sample of 393 households using questionnaires in four wards of the Kigamboni district in Tanzania. Subsequent analyses were descriptive as well as inferential based on binary logistic regression analysis where utilisation of DEMs was predicted for both the high and low social economic status (SES) households by incorporating accessibility constraints, affordances and enablers.

The results show, first, if one assumes energy stacking is not an issue, as households become more constrained towards CEMs utilisation, they shift towards DEMs suggesting that the overall effect is a substitution, and second, the complementarity effect ultimately outweighs the substitution effect as households do not shift from DEMs to CEMs rather stack multiple energy. DEMs flourish in this case study area because those with high income are among those in the lowest SES, and some of those with the highest SES are from among the lowest income category, and all of them end up with more DEMs because shifting towards CEMs require income to complement SES.

Policy-wise, removing hurdles in accessing CEMs such as LPG subsidy programme, gas stove provision to the poor, and enhanced LPG awareness will most likely benefits only those who do not stack energy in cooking while strategies targeting those at the lowest SES such as higher education attainment, empower women as a family decision maker, encourage co-occupancy to enlarge the household size and contain urban growth within certain perimeter will have a significant impact only if they raise both incomes and SES.

Despite of the dominance of DEMs for cooking such as charcoal and firewood in Tanzania, CEMs such as LPG, have emerged as complements or alternatives in the household energy basket. The utilisation of such CEMs is, however, still very low despite the accessibility, cost, environmental and health advantages they offer. Accessibility is not the only factor fuelling CEMs; a complementarity must exist between SES and income for the positive transition towards CEMs to be realised.

The macroscopic properties of dried sand can be correctly modelled when the accurate determination of the microscopic properties is available. The microscopic properties between the particles such as the coefficients of rolling (µ _r) and sliding (µ _s), are numerically determined in two different ways: with and without considering the fluid effect. In an earlier study, the microscopic properties were determined by discrete element method (DEM) and without considering the air effect on the macroscopic properties such as the Angle of Repose. The purpose of this paper is to recalibrate the microscopic properties through a coupling between the DEM and computational fluid dynamics (CFD).

The first step is dedicated to the calibration of the CFD-DEM model through modelling a single particle sedimentation within air, water, and silicon oil. The voidage and drag models, the grid size ratio (D/dx), the domain size ratio (W/D), and the optimum coupling interval between the CFD and DEM were investigated through comparing the CFD-DEM results with the analytical solution and experimental data. The next step is about modelling an Hourglass with the calibrated CFD-DEM model to recalibrate the µ _r and µ _s of dried sand particles.

It was concluded that the air has a minor effect on the macroscopic properties of the dried sand and the µ _r and µ _s that were obtained with the DEM can be utilized in the CFD-DEM simulation.

Utilizing the granulometry of dried quartz sand in the calibration process of the CFD-DEM method has raised the possibility of using the µ _r and µ _s for other applications in future studies.

Unmittelbar nach dem Zusammenbruch im Jahre 1945 setzte in Deutschland eine ungeahnte Ausweitung des Reiseverkehrs ein, dem die an den Schlägen des Krieges leidenden Verkehrsunternehmen in keiner Weise gewachsen waren. Soweit dieser Verkehr nicht der unmittelbaren beruflichen und geschäftlichen Betätigung diente, führte er die Reisenden in die bekannten Feriengebiete Deutschlands, weil diese gleichzeitig die landwirtschaftlich genutzten Gegenden sind und damals die Masse der Flüchtlinge aus dem Osten Deutschlands und die Evakuierten aus den zerbombten Grossstädten und Industriezentren aufgenommen hatten. Diese Form des Reisens nach den Feriengebieten war aber kein echter Fremdenverkehr; denn sie war getragen nicht so sehr von dem Streben nach Erholung, als vielmehr von dem Willen, die in diesen landwirtschaftlichen Gebieten reichlicher vorhandenen Verpflegungsmöglichkeiten auszunützen, vor allem aber von der Notwendigkeit, die versprengten Familienangehörigen wieder zu sammeln. Bei allen diesen Reisen spielte die Kostenfrage, die im normalen Fremdenverkehr immer der ausschlaggebende Faktor zu sein pflegt, keine Rolle. Wer genügend Geld hatte und in den Zielgebieten genügend Sachwerte zum Tausch anbieten konnte, der reiste. Denn das Reisen war billig. Die Preise der Verkehrsmittel waren die einzigen, die — auch ohne Rationierung — weit unter dem allgemeinen Preisniveau lagen.

Defines Deming’s concept of “profound knowledge”, and shows how it addresses both the behavioural and technical dimensions of leadership simultaneously. Suggests that the responsibilities of leaders are to solve problems and to help employees in any way possible by knowing how a system functions, how system components may cause variation, and what the system delivers. Suggests that this knowledge is crucial if the USA is to become a global quality leader.

The dryer feed chute of the pellet plant plays an important role in the pelletizing process. The chute discharges sticky and moist iron ore fines (<1 mm) to the inline rotary dryer for further processing. Since the inception of the installation of the dryer feed chute, the poor flowability of the feed materials has caused severe problems such as blockages and excessive wear of chute liners. This leads to high maintenance costs and reduced lifetime of the liner materials. Constant housekeeping is needed for maintaining the chute and reliable operation. The purpose of this study is to redesign the dryer feed chute to overcome the above challenges.

The discrete element method (DEM) has been used to model the flow of cohesive materials through the transfer chute. Physical experiments have been performed to understand the most severe flow conditions. A DEM material model is also developed for replicating the worst-case material condition. After identifying the key problem areas, concept designs were proposed and simulated to assess the design improvements to increase the reliability of chute operation.

Flow simulations correlated well with the existing flow behavior of the iron ore fines inside the chute. The location of the problematic areas has been validated with that of the previously installed chute. Subsequently, design modifications have been proposed. This includes modification of deflector plate and change in slope and cross-section of the chute. DEM simulations and analysis were conducted after incorporating these design changes. A comparison in the average velocity of particle and force on chute wall shows a significant improvement using the proposed design.

Method to calibrate DEM material model was found to provide accurate prediction and modeling of the flow behavior of bulk material through the real transfer chute. DEM provided greater insight into the performance of the chute especially modeling cohesive materials. DEM is a valuable design tool to assist chute designers troubleshoot and verify chute designs. DEM provides a greater ability to model and assess chute wear. This technique can help in achieving a scientific understanding of the flow properties of bulk solids through transfer chute, hence eliminate challenges, ensuring reliable, uninterrupted and profitable plant operation. This paper strongly advocates the use of calibrated DEM methodology in designing bulk material handling equipment.

This study aims to assess consumers’ beliefs in three Middle Eastern Arab countries regarding attitudinal and behavioural responses towards permission-based direct email marketing (hereafter DEM) and the moderating role of gender in the hypothesised path model.

Structural equation modelling was used to test the hypothesised path model by using data collected from 829 respondents.

The findings show that attitude was found to fully mediate the relationship between beliefs and behavioural responses towards permission-based DEM. Gender moderates the relationship between beliefs and attitudes and responses to permission-based DEM. Notably, female respondents were found to react more actively when exposed to permission-based DEM.

Further qualitative research is needed to learn more about how and why individuals develop behavioural intentions in certain ways towards opt-in DEM. In addition, neuropsychology approaches such as eye-tracking are endorsed for future research to gain more insights and conquer biases associated with self-reporting procedures in countries where such technologies are deemed as legal and ethical to be used with human subjects.

Advertisers promoting products and services in the Middle Eastern Arab context should take further steps to enhance the quality of information (including cultural sensitiveness) and the perceived entertainment value that could be delivered to consumers through permission-based DEM, especially for female internet users. Additionally, this study highly recommends the double opt-in approach to permission-based DEM.

To the best of the authors’ knowledge, this is the first attempt to address the gender role as a moderator of the path depicting the effectiveness of permission-based DEM approach in the Middle East (Arab counties) from beliefs to behavioural responses via attitudes.

The purpose of the study is to investigate the relationship between international financial integration (IFI) index and democracy (DEM) in Pakistan by using long-time series data from 1975 to 2013.

The IFI index is constructed by principal component analysis. IFI consists of foreign direct investment (FDI), remittances (REM) and external debt (ED), whereas the Polity IV index is used for DEM. Johansen and the autoregressive distributed lag method for cointegration methods are used to find a long run relationship. Dynamic ordinary least square (DOLS), fully modified ordinary least square (FMOLS) and canonical regression (CR) have been used to find the nature of the relationship. Rolling window analysis has been done to find the year wise coefficients.

DOLS, FMOLS, canonical regression CR and cointegration results suggest a significant negative long-run relationship between IFI and DEM in Pakistan. Rolling windows analysis highlights that DEM has improved IFI in Pakistan from 2008 to 2013.

This study constructs an index for financial integration using principle component analysis on capital inflows, i.e. FDI, REM, ED, to explore the impact of DEM on IFI in Pakistan from 1975 to 2013. This study investigates for the first time ever the relationship between IFI index and DEM in Pakistan.

The purpose of this paper is to examine several calibration techniques that have been developed to determine the discrete element method (DEM) parameters for slow and rapid unconfined flow of granular conical pile formation. This paper also aims to discuss some of the methods currently employed to scale particle properties to reduce computational resources and time to solve large DEM models.

DEM models have been calibrated against simple bench‐scale experimental results to examine the validity of selected parameters for the contact, material and mechanical models to simulate the dynamic and static behaviour of cohesionless polyethylene pellets. Methods to determine quantifiable single particle parameters such as static friction and the coefficient of restitution have been highlighted. Numerical and experimental granular pile formation has been investigated using different slumping and pouring techniques to examine the dependency of the type of flow mechanism on the DEM parameters.

The proposed methods can provide cost effective and simple techniques to determine suitable input parameters for DEM models. Rolling friction and particle shape representation has shown to have a significant influence on the bulk flow characteristics via a sensitivity analysis and needs to be accessed based on the environmental conditions.

This paper describes several effective known and novel methodologies to characterise granular materials that are needed to accurately model granular flow using the DEM to provide valuable quantitative data. For the DEM to be a viable predictive tool in industrial applications which often contain huge quantities of particles with random particle shapes and irregular properties, quick and validated techniques to “tune” DEM models are necessary.

Provides an explanation of Deming’s Theory of Profound Knowledge, which includes the four core values. Cites these as appreciation for a system, some knowledge of the theory of variation, a theory of knowledge and some knowledge of psychology. Defines leadership and the actions required to implement the Deming leadership method. Argues this implementation will clear most barriers which exist when starting any total quality management programme and will allow managers/supervisors to acquire enough knowledge to make the transformation from supervisory management to leadership excellence. States that only through applying the Deming principles first will any future improvement be successful.

Bulk material-handling equipment development can be accelerated and is less expensive when testing of virtual prototypes can be adopted. However, often the complexity of the interaction between particulate material and handling equipment cannot be handled by a single computational solver. This paper aims to establish a framework for the development, verification and application of a co-simulation of discrete element method (DEM) and multibody dynamics (MBD).

The two methods have been coupled in two directions, which consists of coupling the load data on the geometry from DEM to MBD and the position data from MBD to DEM. The coupling has been validated thoroughly in several scenarios, and the stability and robustness have been investigated.

All tests clearly demonstrated that the co-simulation is successful in predicting particle–equipment interaction. Examples are provided describing the effects of a coupling that is too tight, as well as a coupling that is too loose. A guideline has been developed for achieving stable and efficient co-simulations.

This framework shows how to achieve realistic co-simulations of particulate material and equipment interaction of a dynamic nature.