Today, society is ever-increasing in its use of technology and computers. The increase in technology creates a need for different programming languages with unique properties. The creation of a system may require multiple languages for multiple processes that need to transfer data between one another. There are several solutions for sharing data between processes with their respective strengths and weaknesses. The differences create a problem of needing to understand the data transfer solutions to use them effectively. This thesis addresses the problem of there not existing any guidelines for data transfer solutions. The purpose is to create guidelines for choosing a data transfer solution. The goal is to help software developers find a data transfer solution that fits their needs. The thesis is meant to inform and contribute to the understanding of possible solutions for sharing data between processes. A literature study and practical study were needed to get that understanding. The literature study was conducted to understand the solutions and to be able to compare them. After that, a practical study was performed to work with the solutions and gain experience. The study was meant to gain measurements for later comparisons of data transfer solutions. The measurements followed the comparative criteria of speed , resource usage , and language support . The result was the creation of guidelines that displayed different scenarios based on the comparative criteria. For each situation, there was a recommendation of solutions that would help in the given situation. These results accomplished the goal and purpose by providing guidelines that could help software developers choose a data transfer solution. / Användningen av olika teknologier och datorer ökar konstant i dagens samhälle. Detta skapar ett behov av olika programmeringsspråk med olika egenskaper. Ett projekt kan kräver flera språk för olika processer, så kan programmen behöva kommunicera genom att överföra data sinsemellan. Det finns olika dataöverföringslösningar för att dela data och de har sina svagheter och styrkor. Skillnaderna skapar problemet att en användare behöver förstå dataöverföringslösningar för att använda dem effektivt. Avhandlingen tar upp problemet att det inte finns några riktlinjer för dataöverföringslösningar. Syftet med avhandlingen är att skapa riktlinjer för att välja en dataöverföringslösning. Målet med avhandlingen är att hjälpa mjukvaruutvecklare att välja en dataöverföringslösning som passar deras behov. Avhandlingen är menad att informera och att bidra till förståelsen av dataöverföringslösningar. Därför krävdes det både en litteraturstudie och en praktisk studie. Litteraturstudien utfördes för att få en förståelse för de olika lösningarna och kunna jämföra dem. Den praktiska studien utfördes för att arbeta med lösningarna och lära sig om dem. Arbetet var menat att ta fram mätvärden för att kunna jämföra dataöverföringslösningar. Mätvärdena följde jämnförelsekriterierna hastighet, resursanvändning, och tillgängliga språk. Resultatet av avhandlingen var skapandet av riktlinjerna. Riktlinjerna visar olika situationer baserade på jämförelsekriterierna. För varje situation rekommenderas det en dataöverföringslösning som hjälpte i situationen. Resultatet uppnådde syftet och målet med avhandlingen genom att skapa riktlinjer som hjälper mjukvaruutvecklare att välja dataöverföringslösningar.

Background and problems: The research field of performance management and measurement has primarily focused on financial aspects for a long time, with measurement being the focus. Performance management systems integrate both the aspects of control and measurement, resulting in a broad research area. The lack of research combined regarding the role of the staff manager within the system creates a gap that needs to be explored. Purpose: The purpose of the study is to make a theoretical contribution to the field of performance management systems. The contribution is to examine the role of the staff manager in an implemented performance management system and the achievement of organizational goals. Method: To fulfill the purpose, a qualitative research method with an abductive research approach was used. The study is a case study conducted at Handelsbanken, where the empirical data collection is based on six semi-structured interviews and an internal document.    Conclusion: The role of the staff manager is crucial and more central than previously believed in effectively using a performance management system and achieving organizational goals. By communicating the mission and vision and linking them to the employees' daily work, the system can be efficiently utilized. Daily work is monitored through evaluations, which serve as a fundamental control mechanism in the system.  By strengthening the alignment between employees and the organization, it can result in more desirable organizational outcomes. This can be achieved through a clearer reward system and linking the employees' daily work to the achievement of office goals.

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No description available.

Thermochemical heat storage (TCS) is a technology to convert the heat and cold energy into chemical energy, via reversible chemical reactions, to be stored for heating and cooling applications. TCS technology is gaining interest for its very compact energy storage densities offering attractive thermal energy storage (TES) alternatives to decrease energy-related greenhouse gas(GHG) emissions and contribute to sustainable development.  This thesis is part of the umbrella project “Neutrons for Heat Storage (NHS)”, funded by Nordforsk. The objective of the NHS project at KTH is to design, construct and operate a bench-scale TCS system using strontium chloride (SrCl2)-ammonia (NH3) as the solid-gas reaction pair for low-temperature heat storage applications (40-80 ℃). This system has been thus numerically designed, adapted to practical considerations, and is now being built at Energy Technology, KTH.  Within this background, this thesis, as its primary objective, designs a calculation tool for evaluating the experimental performance of the above described bench-scale TCS system. A thorough explanation of the thesis methodology is presented here, including preparing the composites (SrCl2 impregnated into expanded natural graphite), the system’s risk analysis, and the critical focus is on the systems’ performance evaluation parameters, and the mathematical design of the calculation tool. A review of relevant literature is also conducted to identify the most pertinent performance evaluation parameters of this TCS system. For the consideration of user-friendliness, simplicity, and effectiveness, the calculation tool is designed using Ms. Excel. Here, energy efficiency, reaction advancement, reaction advancement rate, the real thermal energy density per mass, and actual thermal energy density per volume are chosen as the parameters to best-represent the system’s performance (i.e., Key Performance Indicators (KPIs)), calculated based on mass balance and energy balance expressions, primarily. Using this calculation tool, concerning this experimental bench-scale system, the user can visualize the obtained experimental data, calculate the defined KPIs of the system, and seek the potential to improve the current system.  A group of test data is assumed (consulting the reaction equilibrium curve, thus ensuring that they fall within realistic experimental conditions) to check the calculation tool's accuracy and function. For the lack of experimental data, the results of the test data are not ideal. However, thanks to these assumed test data, it is proven that the calculation tool functions correctly. The calculation process can be finished in several minutes, saving a lot of time otherwise required for the data analysis after the experiments. It also functions as the test model to analyze the experimental data.  In conclusion, this project designed and presents a functioning calculation tool to evaluate the experimental performance of a bench-scale experimental TCS system (being built and commissioned at KTH) for the reaction between SrCl2 and NH3. Some suggestions related to future improvements are proposed as well. For instance, the calculation tool is not automatic enough because it involves manual operation at specific points. Therefore, one of the future tasks is to add the ability to identify the reaction pressure vs temperature curve against the equilibrium conditions and defining whether the process is absorption or desorption automatically. Besides, currently, much electrical equipment is employed in the system, which decreases the system's sustainability, whereas, in future work, the layout of the system can be improved. The system's exergy performance is not analyzed in the thesis report, which can be chosen as another future task. / Termokemisk energilagring (TCS) är en teknik som omvandlar värme och kyla till kemisk energi via reversibla kemiska reaktioner, som ska lagras för uppvärmning och kylning. Intresset för TCS-teknik ökar idag för sin mycket kompakta energilagringstäthet som erbjuder ett attraktivt alternativ för termiskenergilagring (TES) för att minska energirelaterade växthusgasutsläpp (GHG) och bidra till hållbar utveckling.  Denna avhandling är en del av paraplyprojektet ”neutroner för värmelagring (NHS)”, finansierat av Nordforsk. Målet med NHS-projektet vid KTH är att designa, konstruera och driva ett TCS-system i bänksala med strontiumklorid (SrCl2) och ammoniak (NH3) som reaktionspar för fast-gas reaktion för värmelagringsapplikationer vid låg temperatur (40-80℃). Detta system har därmed numeriskt utformats och anpassats till praktiska användningsområden och byggs nu på institutionen för Energiteknik på KTH.  Med denna bakgrund utformar detta projekt som sitt primära mål, ett beräkningsverktyg för att utvärdera den experimentella prestandan för det ovan beskrivna TCS-systemet i bänkskala. En grundlig förklaring av metoden presenteras här, inklusive förberedning av kompositerna (SrCl2 impregnerat i en expanderad naturlig grafit) samt systemets riskanalys. Kritiskt fokus ligger på systemens prestandaparametrar och den matematiska utformningen av beräkningsverktyget. En genomgång av relevant litteratur genomfördes också för att identifiera de mest relevanta parametrarna. Med hänsyn till användarvänlighet, enkelhet och effektivitet, är beräkningsverktyget utformat med hjälp av Excel. Här väljs energieffektivitet, reaktionsprogression, förändring av reaktionsprogression, den verkliga termiska energidensiteten per massa och praktisk termisk energitäthet per volym som parametrar för att bäst representera systemets prestanda (dvs Key Performance Indicators (KPIs)). Dessa KPIs beräknades främst baserat på massbalans och energibalansuttryck. Med hjälp av detta beräkningsverktyg för detta TCS-systemet på bänkskala kan användaren visualisera den erhållna experimentella datan, beräkna de definierade KPI:erna för systemet och hitta potentialen att förbättra det nuvarande systemet.  En mängd testdata antogs (genom att hänvisa till reaktionens jämviktskurva, vilket säkerställer att de faller inom realistiska experimentförhållanden) för att kontrollera beräkningsverktygets noggrannhet och funktion. På grund av avsaknaden av experimentella data är resultaten av testdata inte optimala. Men med hjälp av den antagna testdatan är det bevisat att beräkningsverktyget fungerar korrekt. Beräkningen kan avslutas efter några minuter, vilket sparar mycket tid som annars krävs för dataanalysen efter experimenten. Det fungerar också som en testmodell för att analysera experimentdata.  Sammanfattningsvis utformade och presenterade detta projekt ett fungerande beräkningsverktyg för att utvärdera experimentella prestanda för ett experimentellt TCS-system på bänkskala (byggs och tas i drift vid KTH) för reaktionen mellan SrCl2 och NH3. Några förslag relaterade till framtida förbättringar föreslås också. Beräkningsverktyget är till exempel inte helt automatiserat eftersom det behöver manuell inmatning vid specifika punkter. Därför är en av de framtida uppgifterna att lägga till förmågan att identifiera reaktionstrycket mot temperaturkurvan i förhållande till jämvikten och att definiera om processen är absorption eller desorption automatiskt. För närvarande används mycket elektrisk utrustning i systemet vilket minskar systemets hållbarhet, medan systemet i framtiden kan förbättras. Systemets exergiprestanda analyseras inte i rapporten, vilket kan lämnas för framtida arbete.

No / Rapid advances in software systems, wireless networks, and embedded devices have led to the development of a pervasive and mobile cyberspace that provides an infrastructure for anywhere/anytime service provisioning in different domains such as engineering, commerce, education, and entertainment. This style of service provisioning enables users to freely move between geographical areas and to continuously access information and conduct online transactions. However, such a high mobility may cause performance and reliability problems during the execution of transactions. For example, the unavailability of sufficient bandwidth can result in failure of transactions when users move from one area (cell) to another. We present a context-aware transaction model that dynamically adapts to the users' needs and execution environments. Accordingly, we develop a new mobility management scheme that ensures seamless connectivity and reliable execution of context-aware transactions during mobility of users. The proposed scheme is designed and developed using a combination of different queuing models. We conduct various experiments in order to show that the proposed scheme optimizes the mobility management process and increases the throughput of context-aware transactions.

Data Structures and Algorithms (DSA) courses are critical for any computer science curriculum. DSA courses emphasize concepts related to procedural dynamics and Algorithm Analysis (AA). These concepts are hard for students to grasp when conveyed using traditional textbook material relying on text and static images. Algorithm Visualizations (AVs) emerged as a technique for conveying DSA concepts using interactive visual representations. Historically, AVs have dealt with portraying algorithm dynamics, and the AV developer community has decades of successful experience with this. But there exist few visualizations to present algorithm analysis concepts. This content is typically still conveyed using text and static images. We have devised an approach that we term Algorithm Analysis Visualizations (AAVs), capable of conveying AA concepts visually. In AAVs, analysis is presented as a series of slides where each statement of the explanation is connected to visuals that support the sentence. We developed a pool of AAVs targeting the basic concepts of AA. We also developed AAVs for basic sorting algorithms, providing a concrete depiction about how the running time analysis of these algorithms can be calculated. To evaluate AAVs, we conducted a quasi-experiment across two offerings of CS3114 at Virginia Tech. By analyzing OpenDSA student interaction logs, we found that intervention group students spent significantly more time viewing the material as compared to control group students who used traditional textual content. Intervention group students gave positive feedback regarding the usefulness of AAVs to help them understand the AA concepts presented in the course. In addition, intervention group students demonstrated better performance than control group students on the AA part of the final exam. The final exam taken by both the control and intervention groups was based on a pilot version of the Algorithm Analysis Concept Inventory (AACI) that was developed to target fundamental AA concepts and probe students' misconceptions about these concepts. The pilot AACI was developed using a Delphi process involving a group of DSA instructors, and was shown to be a valid and reliable instrument to gauge students' understanding of the basic AA topics. / Ph. D.

In today’s dynamic global environment, organizations need to be agile and adaptive by practicing innovative strategies in order to sustain and remain competitive. One indicator of organizational sustainability is its productivity, which translates into the productivity and performance of employees in the organization. Performance evaluation of employees is an important step in measuring the employee productivity. Such evaluations are in general conducted annually using a performance appraisal system (PAS). The annual appraisal using PAS has two major drawbacks. The first drawback is the long frequency of the appraisal process. As it is an annual affair, the errors such as subjectivity, recency error, bias, halo effect, stereotyping etc. creeps in, and as a result the evaluations will not be proper. The second drawback is with respect to fixation of target/goal achievement. While achieving the targets/goals which are fixed at the beginning of the appraisal period are important, any steps towards achieving such goals are equally important. These drawbacks can be addressed to an extent by having an ongoing or continuous method for performance evaluation of employees. Hence there is a need for continuous performance evaluation of employees (CPEE). Although the importance of CPEE has been highlighted in the literature, we are not aware of any process by which CPEE could be operationalized. In order to implement and sustain, any organizational process, it should produce certain periodic outputs, which is meaningful to its administrators and beneficiaries. In the case of CPEE one such output could be to provide a proper and timely rewards and recognition (R&R). R&R is a motivational tool used for appreciation which could boost employee performance and productivity. Research underline that R&R is strongly and positively correlated to the performance of employees. As defined in thesis, Reward is the materialistic part of the appreciation (such as memento, certificate etc.), while Recognition is the feeling of being appreciated (such as a pat on the back or a public applause). Both Reward and Recognition is considered in unison and considered as mutually inclusive in this thesis. There is some variation of R&R practiced in organizations, known as employee awards. Such awards are motivating enough for the employees. In general, the employee awards are based on nominations from the managers, which are scrutinized by an individual committee and one among the nominated employees is offered the award. Nevertheless employees are often clueless about what performance fetched them the award. In other words the criteria for such awards are often unknown. Similar to PAS, the criteria for such evaluations are developed mostly by the employers with hardly any input from the employees. Additionally the employee awards are heavily dependent upon the PAS and it is mostly an annual affair. Hence the drawbacks for PAS are also applicable for the existing employee awards process. In order to address these drawbacks, R&R should be given in an ongoing and continuous manner. Although the importance and the positive correlation between R&R and employee performance has been established, it has not known to be widely practiced in organizations. This could be due to a lack of proper framework to implement such programs. The CPEE process could be the basis for providing R&R. Therefore this thesis is aimed at developing a comprehensive framework for CPEE to offer R&R. Performance of employee is a sum total of the performances across various dimensions (such as knowledge, skills, attitudes and behaviours). As the performance for employees is a multi-dimensional concept, the criteria for evaluation using CPEE process should also be based on multiple criteria. Therefore in order to effectively address the operational process of CPEE to offer R&R, a multi-criteria decision making (MCDM) method based model needs to be developed. A focused review of the existing literature on performance evaluation of employees substantiated the research problem that there is a lack of proper framework for CPEE to offer R&R. In order to address this research problem, the main objective of this thesis is to develop a comprehensive, formal and objective method to evaluate the employee performance in a continuous manner based on multiple evaluation criteria from the perspectives of employees as well as employers to offer proper and timely reward and recognition to the best performing employee(s). In order to address the main objective of the research, the following objectives are envisaged: 1. To identify the set of variables/criteria with respect to both employees’ and employers’ perspectives and to propose an initial framework for CPEE to offer R&R. 2. To develop a final framework for CPEE to offer R&R based on the initial proposed framework and descriptive research 3 To develop a multi-criteria-decision-making (MCDM) method for the proposed framework for CPEE to offer R&R The scope of this research is limited to Information Technology (IT) organizations due to the alarming rate of attrition and the presence of younger population who are knowledge workers. They expect frequent appreciation and continuous feedback regarding their performance. In this thesis, employees are represented by Software Engineers (SEs) and the employers are represented by Project Managers (PMs). Research Objective 1: In order to address the first research objective a six phased approach is planned. In the first phase, the available literature on existing performance evaluations in general and employee motivations are reviewed to identify the possible variables/criteria for CPEE to offer R&R. This resulted in 51 variables for performance evaluation. As it cannot be confidently asserted whether these variables are applicable to employees of IT organizations, a set of unstructured interviews are conducted with Software Engineers to prepare Case-lets. This Case-let approach with Software Engineers is carried out in the second phase and 7 Case-let reports are prepared. From the analysis of the 7 Case-let reports, 27 variables are identified. As the variables identified from Case-let approach may not represent the entire IT employees, a series of semi structured interviews are conducted among 58 Software Engineers in the third phase to identify further variables/criteria and accordingly 35 variables are identified. In order to obtain the list of variables/criteria based on employers’ perspectives and to validate the set of variables/criteria suggested by Software Engineers, 31 Project Managers are interviewed following semi structured interview method in the fourth phase and 33 variables are identified. In the fifth phase, the variables identified from second to fourth phases are triangulated with those identified from literature (i.e. first phase) which resulted in 33 unique variables that could be used for CPEE of Software Engineers to offer R&R. The final set of 33 variables/criteria are appropriately grouped into variables relating to Demographic Characteristics of Software Engineers (DCSE) and Performance of Software Engineers (PSE). Accordingly, 5 variables related to DCSE and 28 variables related to PSE out of the 33 variables finalized for CPEE to offer R&R, are grouped. Utilizing these grouped sets of variables in DCSE and PSE, an initial framework for CPEE to offer R&R is proposed in the sixth phase. Research Objective 2: In order to validate and to statistically finalize the proposed initial framework, a descriptive research is conducted. For this the importance of each of the identified 33 variables are sought from 443 Software Engineers from 12 IT organizations. A bivariate analysis is planned to analyse the significance of variables of DCSE with the variables of PSE. As there are 28 variables in PSE, they are further grouped with respect to the latent structure using a factor analysis. The factor analysis yielded six factors for measuring PSE. The factors (called as main criteria) are Proactive, Prompt, Resourceful, Responsible, Diagnostic and Dynamic. Based on the bivariate analysis among variables in DCSE and the six main criteria, only three variables, out of five variables of DCSE emerged as significant. Based on the factor analysis and bivariate analysis, the proposed initial framework is modified. Appropriate hypotheses are proposed to indicate the relation between DCSE, PSE and R&R in the modified framework. The modified framework is validated by developing suitable Structural Equation Model (SEM) to verify the hypotheses. The relative influence of DCSE, PSE and R&R are identified based on statistical validation and the framework is finalized. Research Objective 3: As there are six main criteria identified in PSE for CPEE to offer R&R, the proposed framework could be appropriately modelled using MCDM method(s)/models(s). As CPEE is a continuous process, the performance evaluation using CPEE should take only a minimum time for completion of evaluation process, and it should be easy to implement and administer and also should be flexible to accommodate any changes in the criteria or alternatives. These are the preconditions to select the suitable MCDM method(s)/model(s) to operationalize the process of CPEE to offer R&R. In order to select a suitable MCDM method from the available methods, various MCDM methods are screened based on the expected preconditions of the framework. Pugh Matrix Method (PMM) is selected for the CPEE process and is modified to address the basic drawbacks of PMM so as to utilize in this thesis. Accordingly, the MCDM methods: AHP and a Modified Pugh Matrix Method (MPMM) (which are meeting the expected preconditions of the framework such as minimum time, maximum easiness and maximum flexibility) are considered to model the proposed framework for CPEE to offer R&R. The AHP is used to calculate the relative weights and the MPMM is used to compare the performance of employees to provide a relative score. Accordingly, the proposed MCDM based modelling framework for CPEE to offer R&R is demonstrated by developing a suitable example. The MCDM method for CPEE to offer R&R developed in this thesis provides a performance score for every employee for every performance-cycle of CPEE. This score could be stored in a database which could be appropriately utilized during the periodic performance appraisal process using PAS. Overall, the contributions of the research are: (i) a new research problem on CPEE to offer R&R is identified (ii) a set of variables/criteria are identified from both employees and employers perspective, particularly for IT Organizations and an initial framework for CPEE to offer R&R is proposed (iii) a statistically finalized framework for CPEE to offer R&R is presented with the variables/ criteria identified (iv) simple MCDM methods are developed for the operationalization of the proposed framework for CPEE to offer R&R and a possible integration with the organization’s existing PAS is also conceptually presented. (ii) Although the research has accomplished its objectives, there are certain limitations such as (i) the focus of research is limited only to IT organizations, and hence cannot necessarily be generalized, the sampling is based on convenience and assumed to represent the entire IT population in the country and (iii) other MCDM methods are not explored so as to develop the proposed framework. Addressing these could be some of the future research directions in this area.

Indian cities rely predominantly on buses for public transport. The issues of performance measurement and efficiency analyses for the bus company have been gaining significance due to severe operating conditions and financial constraints in which these bus companies provide the service. Performance is defined as the levels of success of the service with respect to different parameters such as quality of service, cost effectiveness and safety. Performance is measured in terms of operational efficiency and financial efficiency. Operational Efficiency of an organization is the ability to utilize its available resources to the maximum extent. Financial Efficiency is a measure of the organization’s ability to translate its financial resources into revenue. Public bus transportation plays a pivotal role in India in bringing about greater mobility both within and between urban and rural areas. Through increased mobility, road transport also contributes immensely to social and economic development of different regions of the country. Public transport is provided by surface road transport using buses by the State Road Transport Undertakings (SRTUs) and by private operators. In this thesis, scientific analysis of the performance of SRTUs is carried out at different levels considering physical and financial parameters through multivariate techniques, non-parametric techniques and qualitative techniques. A comprehensive study on all the SRTUs of Karnataka at depot, division level are done and determined which quantitative method is suited for depot level and division level studies. From quantitative and qualitative studies of SRTUs strategies are developed and recommendations are made to improve the performance of SRTUs. Further, in addition to Bangalore metropolitan transport corporation (BMTC) performance analyses, the routes are analyzed to reduce the dead kilometer. Major contributions from this work: 1. Both inter and intra city operations of the public transport corporation in the state of Karnataka have been exhaustively analysed using operational and financial parameters. 2. Large amount of data over a long period has been collated from State road transport units and a standard format has been developed for collecting both operational and financial parameters for SRTU’s. 3. A generic framework and plan for performance evaluation of SRTU’s has been developed using ratio and benchmarking analysis, and, non-parametric and multivariate techniques like DEA (constant return to scale (CRS) and variable return to scale (VRS)), DEA-principal component analysis (PCA), DEA- bootstrapping. These analyses have been carried out at different levels, like transport corporations level (KSRTC NEKRTC, NWKRTC, BMTC), division level (33 divisions), and Depot level (193 depots). 4. Non parametric and multivariate Models have been developed and validated using DEAP and GAMS software before embarking on the above detailed analyses. 5. Analytical hierarchy approach (AHP), which is multi criteria structured technique, has been adopted to evaluate and analyze performance of the SRTU’s, divisions and depots based on qualitative and quantitative data. 6. User and operator perception studies of different SRTU’s of Karnataka have been done to evaluate the performance of these corporations from qualitative techniques. 7. From these comprehensive non parametric techniques, the efficiency of the SRTU’s have been evaluated and found that KSRTC has been the best operating unit among the SRTU’s considered for the study. The same has been observed from the AHP as well as perception surveys carried out as part of this thesis. 8. Operation and financial performance including profitability studies of Mysore urban transportation (Mysore city transport division) has been carried out before and after implementation of intelligent transport system (ITS). 9. The dead kilometer minimization model was formulated, which is a mixed integer programming problem, to get the optimal solution considering the capacity of the depot and time period of operation for the chosen network. An optimization technique has been developed for solving the dead kilometer problem in the operations of BMTC buses for the Volvo division (division operates 794 schedules). The alternative depot locations have been identified to reduce the dead kilometer, leading to large amount of savings for the corporation. 10. From the detailed analyses using non parametric techniques, multivariate and multi-criteria techniques along with perception surveys, strategies and recommendations have been arrived at to improve performance of the public transport corporations. This thesis consists of nine chapters and they are as below; Chapter 1 provides a brief introduction of public bus transport systems in India, their problems and need for performance evaluation of SRTUs. The impacts study of Mysore ITS, dead kilometer minimization problem for BMTC along with evaluating the performance of SRTUs by quantitative and qualitative data. This chapter provides the objective of the work and scope of the work. The main objectives of this research are 1. To develop a generic framework and plan for evaluation by identifying the performance indicators and data sources for evaluation.

In this thesis, ammonia (NH3) decomposition was assessed as a fuel processing technology for producing on-demand hydrogen (H2) for portable and distributed fuel cell applications. This study was motivated by the present lack of infrastructure to generate H2 for proton exchange membrane (PEM) fuel cells. An overview of past and recent worldwide research activities in the development of reactor technologies for portable and distributed hydrogen generation via NH3 decomposition was presented in Chapter 2. The objective was to uncover the principal challenges relating to the state-of-the-art in reactor technology and obtain a basis for future improvements. Several important aspects such as reactor design, operability, power generation capacity and efficiency (conversion and energy) were appraised for innovative reactor technologies vis-à-vis microreactors, monolithic reactors, membrane reactors, and electrochemical reactors (electrolyzers). It was observed that substantial research effort is required to progress the innovative reactors to commercialization on a wide basis. The use of integrated experimental-mathematical modelling approach (useful in attaining accurately optimized designs) was notably non-existent for all reactors throughout the surveyed openliterature. Microchannel reactors were however identified as a transformative reactor technology for producing on-demand H2 for PEM cell applications. Against this background, miniaturized H2 production in a stand-alone ammonia-fuelled microchannel reactor (reformer) washcoated with a commercial Ni-Pt/Al2O3 catalyst (ActiSorb® O6) was demonstrated successfully in Chapter 3. The reformer performance was evaluated by investigating the effect of reaction temperature (450–700 °C) and gas-hourly-space-velocity (6 520–32 600 Nml gcat -1 h-1) on key performance parameters including NH3 conversion, residual NH3 concentration, H2 production rate, and pressure drop. Particular attention was devoted to defining operating conditions that minimised residual NH3 in reformate gas, while producing H2 at a satisfactory rate. The reformer operated in a daily start-up and shut-down (DSS)-like mode for a total 750 h comprising of 125 cycles, all to mimic frequent intermittent operation envisaged for fuel cell systems. The reformer exhibited remarkable operation demonstrating 98.7% NH3 conversion at 32 600 Nml gcat -1 h-1 and 700 °C to generate an estimated fuel cell power output of 5.7 We and power density of 16 kWe L-1 (based on effective reactor volume). At the same time, reformer operation yielded low pressure drop (<10 Pa mm-1) for all conditions considered. Overall, the microchannel reformer performed sufficiently exceptional to warrant serious consideration in supplying H2 to low-power fuel cell systems. In Chapter 4, hydrogen production from the Ni-Pt-washcoated ammonia-fuelled microchannel reactor was mathematically simulated in a three-dimensional (3D) CFD model implemented via Comsol Multiphysics™. The objective was to obtain an understanding of reaction-coupled transport phenomena as well as a fundamental explanation of the observed microchannel reactor performance. The transport processes and reactor performance were elucidated in terms of velocity, temperature, and species concentration distributions, as well as local reaction rate and NH3 conversion profiles. The baseline case was first investigated to comprehend the behavior of the microchannel reactor, then microstructural design and operating parameters were methodically altered around the baseline conditions to explore the optimum values (case-study optimization). The modelling results revealed that an optimum NH3 space velocity (GHSV) of 65.2 Nl gcat -1 h-1 yields 99.1% NH3 conversion and a power density of 32 kWe L-1 at the highest operating temperature of 973 K. It was also shown that a 40-μm-thick porous washcoat was most desirable at these conditions. Finally, a low channel hydraulic diameter (225 μm) was observed to contribute to high NH3 conversion. Most importantly, mass transport limitations in the porouswashcoat and gas-phase were found to be negligible as depicted by the Damköhler and Fourier numbers, respectively. The experimental microchannel reactor produced 98.2% NH3 conversion and a power density of 30.8 kWe L-1 when tested at the optimum operating conditions established by the model. Good agreement with experimental data was observed, so the integrated experimental-modeling approach used here may well provide an incisive step toward the efficient design of ammonia-fuelled microchannel reformers. In Chapter 5, the prospect of producing H2 via ammonia (NH3) decomposition was evaluated in an experimental stand-alone microchannel reactor wash-coated with a commercial Cs-promoted Ru/Al2O3 catalyst (ACTA Hypermec 10010). The reactor performance was investigated under atmospheric pressure as a function of reaction temperature (723–873 K) and gas-hourly-space-velocity (65.2–326.1 Nl gcat -1 h-1). Ammonia conversion of 99.8% was demonstrated at 326.1 Nl gcat -1 h-1 and 873 K. The H2 produced at this operating condition was sufficient to yield an estimated fuel cell power output of 60 We and power density of 164 kWe L-1. Overall, the Ru-based microchannel reactor outperformed other NH3 microstructured reformers reported in literature including the Ni-based system used in Chapter 3. Furthermore, the microchannel reactor showed a superior performance against a fixed-bed tubular microreactor with the same Ru-based catalyst. Overall, the high H2 throughput exhibited may promote widespread use of the Ru-based micro-reaction system in high-power applications. Four peer-reviewed journal publications and six conference publications resulted from this work. / PhD (Chemical Engineering), North-West University, Potchefstroom Campus, 2015