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A coupled model of a generic bus and an all-fresh air Heat Pump (HP) system was developed to investigate the impact of the cabin set-point temperature on the thermal comfort level and the energy consumption of heating. Predicted Mean Vote (PMV) and Predicted Percentage of Dissatisfied (PPD) from Fanger’s model were used to quantify the comfort level inside the cabin. Different heating strategies based on fixed and variable set-point temperature were examined for an all-fresh air HP under different outdoor temperatures. The results indicate that for the studied all-fresh air HP, adopting a proper heating strategy based on variable set-point temperature could reduce the power demand up to 61% when the outdoor temperature is -5 °C.

In the UK local authorities are being incentivized to purchase low emission vehicles through schemes such as the Ultra Low Emissions Bus (ULEB) scheme. To qualify vehicles must prove they meet certain emissions limits over a pre-described drive cycle. One of the key factors that will impact vehicle performance is the operation of the Heating Ventilation and Air Conditioning (HVAC) system, a large consumer of energy in the system, thus it is vital to have an understanding of the thermal behavior of the cabin and HVAC loads required to maintain comfortable conditions. This paper outlines a lumped parameter model of a generic city bus for use in determining such loads and assisting in the creation of control strategies to minimize energy consumption. Using steady state analysis it is possible to determine the average power consumption required to maintain an internal cabin temperature over a single MLTB drive cycle. Dynamic analysis shows that by changing the HVAC strategy it is possible to reduce the energy consumption by removing the need to operate the system at full power for the entire duration of the cycle. By implementing a hysteresis based control strategy that over heats the environment then switches to a low power mode to allow the temperature to recover the model was able to demonstrate potential energy savings of up to 26.6% when compared to the baseline case operating at a constant steady power output.

Air circulation inside the buses’ cabin seems to negatively affect the spread of contagious diseases, such as the COVID-19 virus and raises valid health concerns over using public transportations. Employing all-fresh air and avoiding to recirculate it could help with lowering the exposure time and the virus density in buses; however, it makes the heating more challenging, especially in Electric buses. Here a Baseline and a proposed Recovery Heat Pump (BHP and RHP, respectively) systems in a generic single decker bus were modeled to investigate their dynamic performance and the cabin’s conditions using 100% fresh air. Simulink and Simscape toolbox from MATLAB (R2020a) were used to build up the real-time model by integrating an HP system with a cabin sub-model. The cabin is modeled using a moisture air network and is coupled with the HP to exchange heat with the refrigerant through the condenser. For both cases, 100% fresh air flows through the condenser into the cabin. In BHP the evaporator is exposed to 100% cold fresh air, while in RHP the warm air from the cabin passes through the evaporator before being vented outside. Both cases were studied for different ventilation modes in low and medium occupancy levels. Results indicate that RHP shows superior performance compared with BHP. Under the studied operational conditions, RHP reduced the power requirement, warm-up time, and operation time by 36%-6% (at most-at least), 57%-7%, and 39%-13%, respectively.

The bus sector is currently lagging behind when it comes to implementing autonomous systems for improved vehicle safety. However, in cities such as London, public transport strategies are changing, with requirements being made for advanced driver-assistance systems (ADAS) on buses. This study discusses the adoption of ADAS systems within the bus sector. A review of the on-road ADAS bus trials shows that passive forward collision warning (FCW) and intelligent speed assistance (ISA) systems have been successful in reducing the number of imminent pedestrian/vehicle collision events and improving speed limit compliance, respectively. Bus accident statistics for Great Britain have shown that pedestrians account for 82% of all fatalities, with three quarters occurring with frontal bus impacts. These statistics suggest that the bus forward collision warning system is a priority for inclusion in future vehicles to enhance the driver’s direct vision, and to increase reaction time for earlier brake application. Almost 80% of bus occupant casualties occurred in non-impact situations, mainly during acceleration/deceleration events. Therefore, care must be taken in implementing autonomous braking in buses, to ensure that it does not cause an increased number of deceleration events beyond the safe stability limits for passengers. Real on-road drive cycle data has shown that while instances of unsafe braking events do not occur regularly, there are instances of braking events that would present a hazard to both seated and standing passengers, therefore systems that would mitigate these issues would have real benefits to both passenger comfort and safety. During tests to simulate the use of the vehicle retarder for an autonomous braking system, deceleration rates largely remained safely within standee and seated passenger stability limits, whereas an emergency stop test showed a peak deceleration 3.5 times the limit of a standee supported by a vertical handrail, and 4 times the limit for a forward/backward facing seated passenger.

This work investigates a solar combined heat and power systems based on hybridphotovoltaic-thermal heat pump systems for the simultaneous provision of spaceheating and electricity to residential homes. The analysed system connects aphotovoltaic-thermal (PVT) panel, through a PVT water tank, to a heat pump. Thestudy is based on quasi-steady state heat transfer and thermodynamic analysis that takes incremental time steps to solve for the fluids temperature changes from the heat pump and the solar PVT panels. The effects of solar irradiance, size of the water tank and the water flow rate in the PVT pipes (laminar and turbulent) on the performance of the system are analysed. Particular focus is made towards the efficiency (electrical and thermal) of the PVT and the COP of the heat pump. Results show that the minimum COP of the heat pump is 4.2, showing the high performance of the proposed hybrid system. Increasing the water flowrate through the PVT panel from 3L/min (laminar) to 17L/min (turbulent) increases the PVT’s total efficiency (electrical + thermal) from 61% to 64.5%. Increasing the size of the PVT water tank from 1L to 100L, increases the total efficiency of the PVT panel by 6.5%.

This study performs a combined 0-dimensional/3-dimensional modelling ap-proach to investigate the fluid flow and heat transfer characteristics of a busthermal management systems. The 3-dimensional model is deployed to de-velop new correlations for the heat transfer coefficient (Colburn-j factor) andthe friction factor (Fanning-f factor) at the air-side of the multi-louver ra-diator and charge-air cooler. The effect of the fan operation is also takeninto account. The existing correlations in the literature developed for carswhere the radiator and charge-air cooler are placed in the front section ofthe vehicle exposed to a uniform incoming air flow. While in buses, thesecomponents are placed at the vehicle rear section and in contact with a turbu-lent and non-uniform air flow, highlighting the need for development of newColburn-j factor and the Fanning-f factor for air flow within the louvered finsin these two components The coefficients developed are incorporated into the0-dimensional model to predict the thermal characteristics of the bus under-hood for a range of operating conditions. The 0-dimensional model simulatesthe heat interaction of the multiple thermodynamic systems. Thus, a betterunderstanding of the thermal management is achieved by investigating the energy distribution within the engine compartment and describing the per-formance of the thermal systems. The 0-dimensional/3-dimensional model isexamined under the peak brake power condition. A coolant mass flow rate of3.74 kg/s and fans speed of 4000rpm are the most optimum results since thecoolant’s temperature is decreased by 5◦C and the parasitic losses are keptat minimum.

The story extracts presented here reflect the experiences of five teacher candidates from Japan on a short-term study abroad program focusing on developing English-language skills while exploring Canadian culture and English-language teaching methods. Narrative inquiry techniques were employed to gather data related to the participants’ program experiences. These data were crafted into stories with participant input and review. The story extracts relate to intercultural interactions, First Nations culture, teaching methods, meals, and extracurricular activities. On reflection, the narrative inquiry process employed in this study worked as both a research and pedagogical tool to uncover meaningful program experiences.

With increasing numbers of students from culturally and linguistically diverse backgrounds enrolling in English for Academic Purposes (EAP) programs, understanding intercultural communicative competence can contribute to developing effective EAP pathways to higher education. This review of the literature was carried out to synthesize and uncover emerging themes related to intercultural communicative competence and EAP over a 20-year period from 1996 to 2016. A careful search found 15 scholarly works related to this topic. Papers were coded and analyzed for their key findings to reveal eight major themes: miscommunication, ethnocentrism, acculturation, awareness, ethnorelativism, identity, teaching and learning, and academic success. The scant literature related to the topic points to the need for further research. However, the findings do indicate how EAP practitioners can move away from ethnocentric perceptions and programs of study fixed on acculturation toward ethnorelative understandings and EAP classrooms that support intercultural awareness for both teachers and students., Il y a un nombre croissant d’étudiants d’origines culturelles et linguistiques diverses dans les programmes d’anglais à des fins académiques (PAFA). Par conséquent, la compréhension des compétences en communication interculturelle peut contribuer à développer les voies d’accès efficaces au PAFA vers les études post-secondaires. Cette recension des écrits a été réalisée pour synthétiser et découvrir les thèmes émergents liés à la compétence en communication interculturelle et au PAFA pendant une période de 20 ans, de 1996 à 2016. Notre recherche a trouvé 15 articles liés à ce sujet. Les articles ont été codés et analysés pour leurs résultats clés afin de révéler huit thèmes principaux : mauvaise communication, ethnocentrisme, acculturation, sensibilisation, ethnorelativisme, identité, enseignement et apprentissage, et réussite scolaire. Les écrits scientifiques limités liés au sujet font ressortir le besoin de recherches supplémentaires. Cependant, les résultats ont indiqué les façons dont les praticiens du PAFA pouvaient s’éloigner des perceptions ethnocentriques et des programmes d’études axés sur l’acculturation vers des compréhensions ethnorelatives et des salles de classe du PAFA qui favorisent la sensibilisation interculturelle des enseignants et des élèves.

Generally, >40% of the useful energy (cooling engine and exhaust gases) are wasted by a biogas power plant through the cooling radiator and the exhaust gases. An efficient way to convert this waste heat into work and eventually electricity is the use of an organic Rankine cycle (ORC) power system. Over the last few years, different architectures have been widely investigated (subcritical, wet expansion and trans-critical). Despite the promising performances, realistic economic and technical constraints, also related to the application, are required for a meaningful comparison between ORC technologies and architectures. Starting from the limited literature available, the aim of the present paper is to provide a methodology to compare sub-critical, trans-critical and wet expansion cycles and different types of expanders (both volumetric and turbomachinery) from both technical and economic point of view, which represent one of the main novel aspects of the present work. In particular, the paper focuses on the thermo-economic optimization of an ORC waste heat recovery unit for a 500 kWe biogas power plant located in a detailed regional market, which was not investigated yet. By means of a genetic algorithm, the adopted methodology optimizes a given economic criteria (Pay-Back Period, Net Present Value, Profitability Index and Internal Rate of Return) while respecting technical constraints (expander limitations) and thermodynamic constraints (positive pinch points in heat exchangers, etc.). The results show that optimal ORC solutions with a potential of energy savings up to 600 MWh a year and with a pay-back period lower than 3 years are achievable in the regional market analysed.

Stainless steels can form a protective oxide layer when exposed to a high temperature oxidising environment, this protective layer forms a diffusion barrier and slows the oxidation of the alloys in harsh environments. This characteristic has made stainless steels one of the most commonly used alloys for high temperature industrial applications. In this work, a systematic testing procedure has been used to investigate the high temperature oxidation of two commonly used grades of stainless steel, 316 and 310. Samples of each alloy have undergone isothermal testing in air at 1050°C, 1150°C and 1250°C for a range of time periods up to 8h. The oxidation kinetics were also investigated using thermo-gravimetric analysis in air at the same temperatures for 8h. The oxide layers formed on the samples were characterised using X-Ray diffraction, Scanning electron microscopy and energy dispersive spectroscopy. Information derived from oxide layer characterisation was used to explain any differences between the two alloys in terms of oxidation rate and overall alloy performance in the high temperature environment.

This study investigates the application of a circular economy in a rural agricultural setting in Northern Ireland, centered around a typical anaerobic digestion (AD) plant, showing its potential to provide renewable energy for the electricity and transport fuel needs of an average dairy farm and associated milk processing facilities. It was calculated that a typical AD plant has the potential to fuel 22 average sized dairy farms in Northern Ireland, equating to the production, transport, and processing of 51,986 litres of milk per day. The feedstock needs of the AD plant can be provided by the local farming community.

A systematic testing procedure has been employed to investigate the high temperature oxidation kinetics of AISI 316L. Thermo-gravimetric (TG) analysis was carried out at 950°C, 1050°C, 1150°C and 1250°C for 8h. Alongside this, isothermal furnace treatments were carried out on samples of the same material at the same temperatures for time periods of 0.5h, 1h, 2h, 4h and 8h. Changes in oxidation kinetics were observed on mass gain curves plotted from data derived from the TG analysis. When a change in oxidation kinetics was identified, the structure, thickness and composition of the oxides formed on the isothermal treatment samples at time periods before and after the change occurred could be studied. It was found that this systematic testing procedure provided a great deal of useful information allowing more meaningful conclusions to be made on the influence of oxide layer thickness, structure and composition on high temperature oxidation kinetics.

While service learning platforms hold great potential for adult learners of English as an additional language (EAL), there has been little research to date related to the impact of these programs on adult newcomers’ linguistic and social development. The Multicultural Café was a food service learning platform for adult EAL learners operated over a 7-month period at a regional college in the British Columbia interior. The café was developed to provide adult immigrant learners of EAL with an opportunity to authentically engage in using English to provide a valued service to the local community. The current study was conducted to explore the impact of the service learning experience from the perspective of the participants. Using a qualitative case study research design, data were gathered from participants (n = 10) through a questionnaire, semistructured interviews, and a focus group. Data were transcribed, coded, and collected into emerging themes. Opportunities for authentic interactions with customers and with other volunteer coworkers emerged as two of the primary outcomes of the service learning experience. Incorporating the service learning opportunity of the Multicultural Café into the participants’ English language learning experiences appeared to enhance their interactions within the college community. Les cadres d’apprentissage par le service communautaire sont très prome eurs pour les apprenants adultes d’anglais langue additionnel (ALA); pourtant, peu de recherche a porté sur l’impact de ces programmes sur le développement linguistique et social des nouveaux arrivants d’âge adulte. Le Café Multiculturel a constitué, pendant une période de 7 mois, un milieu d’apprentissage par le service pour des apprenants adultes d’ALA dans un collège régional de l’intérieur de la Colombie-Britannique. Le café a été développé pour fournir aux immigrants adultes apprenant l’ALA l’occasion de communiquer authentiquement en anglais tout en offrant un service important à la communauté locale. La présente étude a porté sur l’impact de l’expérience d’apprentissage par le service selon la perspective des participants. Employant un plan de recherche qualitative visant une étude de cas, nous avons recueilli des données de participants (n = 10) par le biais d’un questionnaire, d’entrevues semi-structurées et d’un groupe de discussion. Les données ont été transcrites, codées et rassemblées selon des thèmes qui s’y dégageaient. Deux des résultats principaux de l’expérience de l’apprentissage par le service consistaient en les occasions d’interactions authentiques avec les clients et avec les autres collègues bénévoles. L’intégration, dans le parcours pédagogique des apprenants d’anglais, de l’expérience de l’apprentissage par le service au Café Multiculturel semble avoir mis en valeur leurs interactions au sein de la communauté du collège.

Simulation is a well-established and effective approach to the development of fuel-efficient and low-emissions vehicles in both on-highway and off-highway applications. The simulation of on-highway automotive vehicles is widely reported in literature, whereas research relating to non-automotive and off-highway vehicles is relatively sparse. This review paper focuses on the challenges of simulating such vehicles and discusses the differences in the approach to drive cycle testing and experimental validation of vehicle simulations. In particular, an inner-city diesel-electric hybrid bus and an ICE (Internal Combustion Engine) powered forklift truck will be used as case studies. Computer prediction of fuel consumption and emissions of automotive vehicles on standardised drive cycles is well-established and commercial software packages such as AVL CRUISE have been specifically developed for this purpose. The vehicles considered in this review paper present new challenges from both the simulation and drive-cycle testing perspectives. For example, in the case of the forklift truck, the drive cycles involve reversing elements, variable mass, lifting operations, and do not specify a precise velocity-time profile. In particular, the difficulties associated with the prediction of productivity, i.e. the maximum rate of completing a series of defined operations, are discussed. In the case of the hybrid bus, the standardised drive cycles are unrepresentative of real-life use and alternative approaches are required in the development of efficient and low-emission vehicles. Two simulation approaches are reviewed: the adaptation of a standard automotive vehicle simulation package, and the development of bespoke models using packages such as MATLAB/Simulink.

With a transition towards electric vehicles for the transport sector, there will be greater reliance put upon battery packs; therefore, battery pack modelling becomes crucial during the design of the vehicle. Accurate battery pack modelling allows for: the simulation of the pack and vehicle, more informed decisions made during the design process, reduced testing costs, and implementation of superior control systems. To create the battery cell model using MATLAB/Simulink, an electrical equivalent circuit model was selected due to its balance between accuracy and complexity. The model can predict the state of charge and terminal voltage from a current input. A battery string model was then developed that considered the cell-to cell variability due to manufacturing defects. Finally, a full battery pack model was created, capable of modelling the different currents that each string experiences due to the varied internal resistance. The model was then validated with real-life data from the “Hill Route” section of the First Group Millbrook Fuel Economy Test Version 5.0 drive cycle of a mild hybrid electric bus. Results showed a strong correlation with the measured data and both the state of charge and terminal voltage simulations of the model. For the string model, results showed that there was a slight variance in the state of charge between cells in a string with varied capacities. However, terminal voltages between cells did not vary significantly with variances in internal resistance. Future work includes the creation of a thermal sub-model and an ageing sub-model, which considers whether the location of a cell within a pack has a correlation with its degradation. These sub-models will then be integrated and used as a full battery pack model.

Learned irrelevance and latent inhibition experiments suggest animals learn which stimuli signal important outcomes and which are best ignored. However, stimuli usually derive their importance from the specific purposes they serve. For example, a stimulus that signals water might be very relevant to an animal when it is thirsty but a distraction when the same animal is hungry. This thesis reports three experiments testing for a role of motivational state in moderating learned irrelevance effects in rats. Experiment 1 used an excitatory conditioning procedure and found only weak evidence of an influence of motivational state during pre-exposure on conditioning. However, when this procedure was modified slightly and repeated in Experiment 2, strong evidence was found that rats showed more evidence of learned irrelevance in conditioning when the reinforcer was related to the motivational state in which conditioned stimuli were pre-exposed. This finding was further complemented by results obtained from Experiment 3 using an inhibitory appetitive conditioning procedure. The findings partially replicate previous studies of latent inhibition suggesting that motivation and attention interact in fundamental ways.

Samples of locally sourced UK Diesel fuel spiked with the two organic compounds 2-(butan-2-yl)-1-(decyloxy)-4-(triphenylmethyl)benzene (TPMB) and 1,3-dibromotetrafluorobenzene (BFB) were subjected to laboratory-scale distillations to assess the suitability of TPMB and BFB as effective markers of Diesel fuel. Industrial-scale distillations of these spiked Diesel samples were performed to establish whether TPMB and BFB could be successfully and cost-effectively separated from Diesel on a significantly larger scale. Diesel distillate does not contain any TPMB; newly formulated performance criteria of an ideal, distillation resistant fuel marker clearly reject TPMB as a marker suitable for the tagging of Diesel. In contrast, BFB is retained in all fractions of distilled Diesel and largely satisfies the performance criteria of a distillation resistant fuel marker. BFB consequently functions as a significantly better fuel marker than TPMB for the tagging of Diesel. It is demonstrated that distillation is also a highly effective means of removing current overt dye markers. Conservative estimates suggest that an appropriately equipped laundering facility for the distillative removal of fuel markers or vice versa fuel from marked Diesel offers the potential of generating a vastly lucrative, multi-million pound annual profit.