The aim of this study is to investigate whether a combination of agile system development methodologies (ASDMs) and project management methodologies (PMMs) can be used to develop a hybrid APMM that will have the ability to deliver information technology (IT) projects successfully in a constantly changing business and project environment. To achieve this objective, a literature review was conducted on the relatively well–established ASDMs by firstly defining a SDM and an ASDM. Each ASDM and its effectiveness are described, after which ASDMs in general are evaluated by considering their area of application, advantages and disadvantages. A comparison is then done of the seven different ASDMs using the four elements of an SDM (Huisman & Iivari, 2006:32) to emphasise some of the main similarities and differences amongst the different ASDMs. The seven ASDMs investigated in this study are Dynamic System Development Methodology, Scrum, Extreme Programming, Feature Driven Development, Crystal ASDMs ? Crystal Clear and Crystal Orange in particular, Adaptive Software Development and Lean Development. A literature review was also conducted on two structured and relatively well–established PMMs, PMBOK and PRINCE2, and a relatively new PMM called Agile Project Management. Each PMM is evaluated by considering their area of application, advantages, disadvantages and integration with other methodologies, after which a comparison is made of the different PMMs. The research was conducted by following a mixed methods research plan, which included the mixed methods research paradigm (combination of the interpretive research paradigm and the positivistic research paradigm), research methods (design science, case study and survey), quantitative and qualitative data–collection techniques (interviews and questionnaires), and dataanalysis techniques (cross–case and statistical). The reasons that projects fail and critical project success factors were studied and summarised to form the critical project success criteria, which were used to create the agile project success criteria. The ASDM best practice and PMM best practice frameworks were created by identifying whether a certain ASDM or PMM would satisfy a specific agile project success factor (APSF) of the agile project success criteria. The findings of each APSF in the respective frameworks were used as a foundation to develop a hybrid APMM (ver. 0) that would address the agile project success criteria. The hybrid APMM (ver. 0) was developed interpretively using design science (research approach) and constructivism by combining the strengths, addressing the weaknesses and bridging the gaps identified in the frameworks. The hybrid APMM (ver. 0) was then evaluated and improved by conducting an interpretive case study, which entailed interviewing participants from large and small organisations. Once the qualitative data collected had been analysed using cross–case analysis, the findings were incorporated in order to create an improved hybrid APMM (ver. 1). The hybrid APMM (ver. 1) too was evaluated and improved by conducting a survey, which entailed administering questionnaires to various respondents in order to collect quantitative and qualitative data. The findings of the statistical analysis of the data were also used to improve the hybrid APMM (ver. 1), resulting in the final hybrid APMM (ver. 2). This study demonstrates that a combination of ASDMs and PMMs can be used to develop a hybrid APMM with the ability to deliver IT projects in a constantly changing project and business environment. / Thesis (Ph.D. (Computer Science))--North-West University, Potchefstroom Campus, 2012.

[IT] Importanti cambiamenti sociodemografici, come la crescita della popolazione mondiale e l’urbanizzazione, stanno incrementando il fabbisogno di alimenti a livello mondiale. In contemporanea si sta assistendo ad una profonda trasformazione della dieta umana che tende sempre più a prediligere prodotti di origine animale, frutta e verdura al posto dei cereali. In quest’ottica, serre e stalle per l’allevamento intensivo possono ricoprire un ruolo di spicco, in quanto in grado di produrre tali alimenti con dei rendimenti decisamente maggiori rispetto a quelli che caratterizzano la produzione di vegetali in campo aperto e l’allevamento estensivo. Tra i vari fattori che contribuiscono ad incrementare la produttività di questi edifici agricoli vi è il controllo delle condizioni climatiche interne. Tale controllo del clima interno avviene, in molti casi, attraverso sistemi meccanici il cui utilizzo causa un considerevole consumo energetico che costituisce una minaccia per la transizione verso un’agricoltura più sostenibile. L’obiettivo generale di questa tesi è, quindi, di contribuire alla transizione verso un’agricoltura più sostenibile attraverso il miglioramento della prestazione energetica per il controllo climatico di serre e stalle per l’allevamento intensivo. Per raggiungere tale obiettivo, è stato adottato un triplice approccio basato su un’analisi di letteratura, campagne sperimentali di monitoraggio ed attività di modellazione energetica. L’analisi di letteratura è stata svolta con il fine di districare la complessa rete di relazioni esistente tra controllo climatico e altri domini di interesse della produzione agricola. Il nesso tra prestazione energetica e controllo climatico è stato approfondito analizzando dei set di dati reali acquisiti in una serra e due porcilaie attraverso campagne di monitoraggio. Questo nesso è stato ulteriormente approfondito adottando un approccio numerico che ha portato allo sviluppo e validazione di tre modelli di simulazione energetica per serre, per stalle da polli da carne e per stalle da suini da ingrasso. Ciascun modello di simulazione integra le principali caratteristiche tipiche di tali edifici per stimare con accuratezza i profili temporali delle condizioni ambientali interne e del consumo di energia termica ed elettrica. Le potenzialità di questi modelli nel migliorare la prestazione energetica e le condizioni climatiche di serre e stalle sono state esplorate analizzando specifiche problematiche relazionate al consumo energetico. Il modello energetico per le stalle per polli da carne, infatti, è stato adottato per valutare le potenzialità di un nuovo approccio per la progettazione energeticamente efficiente dell’involucro basato sull’energia primaria. Lo stesso modello è stato usato per valutare la variazione del consumo energetico causata dall’adozione di una strategia di ventilazione mirata al miglioramento del benessere dei polli allevati attraverso la riduzione della concentrazione interna di gas nocivi. Questa tesi contribuisce alla transizione verso una agricoltura più sostenibile fornendo nuove conoscenze e strumenti necessari al miglioramento della prestazione energetica per controllo climatico di serre e stalle per l’allevamento intensivo. Le analisi svolte, infatti, quantificano potenziali riduzioni del consumo energetico ottenibili attraverso l’implementazione di misure di efficientamento energetico, sia a livello di involucro (isolamento termico) che a livello di sistema di controllo climatico (ventilatori a portata variabile). Ulteriori misure per l’efficientamento energetico potrebbero essere valutate attraverso tali modelli che rappresentano importanti risultati di questa ricerca. Essi, infatti, potrebbero avere ricadute positive a livello locale in quanto vari portatori d’interesse (agricoltori, ingegneri e fabbricanti) potrebbero adottarli come strumenti di supporto alle decisioni per valutare nuove tecnologie, strategie e soluzioni mirate alla diminuzione del consumo energetico di serre e stalle. Questi nuovi modelli rappresentano anche un solido punto di partenza per future ricerche in questo campo. Futuri sviluppi potrebbero portare alla creazione di ulteriori moduli di calcolo per valutare altri aspetti, come la variazione della produttività, l’emissione di contaminanti e il benessere animale. Le nuove conoscenze generate in questa tesi potrebbero avere ricadute positive anche a livello globale, in quanto potrebbero rappresentare i fondamenti tecnici per nuovi quadri normativi e schemi di incentivi mirati al miglioramento della performance energetica di edifici agricoli controllati climaticamente attraverso una strategia di tipo top-down. / [ES] Importantes cambios sociodemográficos están conduciendo hacia un considerable crecimiento de la demanda de alimentos a nivel mundial. Al mismo tiempo se está observando una profunda transformación de la dieta humana, que tiende a incluir más productos de origen animal, fruta y verdura. Invernaderos y granjas de ganadería intensiva pueden desempeñar un papel principal, debido a que proporcionan los productos agrícolas necesarios con rendimientos notablemente mayores que los de la producción en campo abierto y de la ganadería extensiva. Entre los factores que contribuyen a incrementar la productividad de estos edificios agrícolas se sitúa el control de las condiciones climáticas internas. Dicho control se realiza a través de sistemas mecánicos cuyo uso causa un considerable consumo energético que representa una amenaza para la transición hacia una agricultura sostenible. El objetivo de esta tesis es contribuir a la transición hacia una agricultura más sostenible a través de la mejora de la prestación energética por control climático de invernaderos y granjas de ganadería intensiva. Para alcanzar dicho objetivo, se ha adoptado un enfoque triple basado en un análisis de literatura, campañas experimentales de monitorización y actividades de modelización energética. El análisis de literatura se ha llevado a cabo con el fin de desentrañar la red de relaciones existentes entre el control climático y otros dominios de interés de la producción agrícola. El nexo entre prestación energética y control climático se ha acometido analizando conjuntos de datos reales, adquiridos en un invernadero y dos granjas de cerdos. El análisis de dicho nexo se ha profundizado adoptando un enfoque numérico que ha llevado al desarrollo y validación de tres modelos de simulación energética para invernaderos y para granjas de pollos y cerdos. Las potencialidades de estos modelos para la mejora de las prestaciones energéticas y las condiciones climáticas se han explorado analizando problemáticas específicas. El modelo energético para granjas de pollos se ha adoptado para el diseño energéticamente eficiente de la envolvente de este tipo de edificio. El mismo modelo se ha usado para evaluar las variaciones de consumo energético causadas por la adopción de una estrategia de ventilación orientada a la mejora del bienestar de los pollos. Esta tesis contribuye a la transición hacia una agricultura más sostenible proporcionando nuevos conocimientos e instrumentos para la mejora de la prestación energética para el control climático de invernaderos y granjas. Los análisis realizados cuantifican potenciales disminuciones del consumo energético alcanzables a través de la implementación de medidas para la eficiencia energética a nivel de envolvente (aislamiento térmico) y a nivel de sistema de control climático (ventiladores con caudal variable). Ulteriores medidas para la eficiencia energética podrían evaluarse a través de dichos modelos que representan importantes resultados de esta investigación. Estos modelos podrían tener repercusiones positivas a nivel local, ya que muchas partes interesadas (agricultores, ingenieros y fabricantes) podrían adoptarlos como instrumentos de apoyo a la toma de decisiones para evaluar nuevas tecnologías y estrategias orientadas a la disminución del consumo energético. Estos nuevos modelos representan también un sólido punto de partida para futuras investigaciones en este campo. Futuros desarrollos podrían implementar nuevos módulos de cálculos para evaluar otros aspectos, como la variación de la productividad, la emisión de contaminantes y el bienestar animal. Los nuevos conocimientos generados en esta tesis podrían tener repercusiones positivas incluso a nivel global, puesto que podrían representar los fundamentos técnicos para nuevos marcos normativos y sistemas de incentivos orientados a la mejora de la prestación energética de edificios agrícolas controlados climáticamente a través de una estrategia de tipo top-down. / [CA] Importants canvis sociodemogràfics estan conduint cap a un considerable creixement de la demanda d'aliments a nivell mundial. Al mateix temps s'està observant una profunda transformació de la dieta humana, que tendeix a incloure més productes d'origen animal, fruita i verdura. Hivernacles i granges de ramaderia intensiva poden exercir un paper principal, pel fet que proporcionen els productes agrícoles necessaris amb rendiments notablement majors que els de la producció en camp obert i de la ramaderia extensiva. Entre els factors que contribueixen a incrementar la productivitat d'aquests edificis agrícoles se situa el control de les condicions climàtiques internes. Aquest control del clima intern es realitza a través de sistemes mecànics, l'ús dels quals causa un considerable consum energètic que representa una amenaça per a la transició cap a una agricultura sostenible. L'objectiu general d'aquesta tesi és contribuir a la transició cap a una agricultura més sostenible a través de la millora de la prestació energètica per al control climàtic d'hivernacles i granges de ramaderia intensiva. Per a aconseguir aquest objectiu, s'ha adoptat un enfocament triple basat en una anàlisi de literatura, campanyes experimentals de monitoratge i activitats de modelització energètica. L'anàlisi de literatura s'ha dut a terme amb la finalitat de desentranyar la complexa xarxa de relacions existents entre el control climàtic i altres dominis d'interés de la producció agrícola. El nexe entre prestació energètica i control climàtic s'ha analitzat amb conjunts de dades reals, adquirides en un hivernacle i dues granges de porcs. L'anàlisi d'aquest nexe s'ha aprofundit encara més adoptant un enfocament numèric que ha portat al desenvolupament i validació de tres models de simulació energètica per a hivernacles i per a granges de pollastres i porcs d'engreixament. Les potencialitats d'aquests models per a la millora de les prestacions energètiques i les condicions climàtiques s'han explorat analitzant problemàtiques específiques. El model energètic per a granges de pollastres s'ha adoptat per al disseny energèticament eficient de l'envolupant d'aquesta mena d'edifici. El mateix model s'ha usat per a avaluar les variacions de consum energètic causades per l'adopció d'una estratègia de ventilació orientada a la millora del benestar dels pollastres. Aquesta tesi contribueix a la transició cap a una agricultura més sostenible proporcionant nous coneixements i instruments per a la millora de la prestació energètica per al control climàtic d'hivernacles i granges. Les anàlisis realitzades quantifiquen potencials disminucions del consum energètic assolibles a través de la implementació de mesures per a l'eficiència energètica tant a nivell d'envolupant (aïllament tèrmic) com a nivell de sistema de control climàtic (ventiladors amb cabal variable). Ulteriors mesures per a l'eficiència energètica podrien avaluar-se a través d'aquests models que representen importants resultats d'aquesta investigació. Aquests models podrien tindre repercussions positives a nivell local, ja que moltes parts interessades (agricultors, enginyers i fabricants) podrien adoptar-los com a instruments de suport a la presa de decisions per a avaluar noves tecnologies i estratègies orientades a la disminució del consum energètic d'hivernacles i granges. Aquests nous models representen també un sòlid punt de partida per a futures investigacions en aquest camp. Futurs desenvolupaments podrien implementar nous mòduls de càlculs per a avaluar altres aspectes, com la variació de la productivitat, l'emissió de contaminants i el benestar animal. Els nous coneixements generats en aquesta tesi podrien tindre repercussions positives fins i tot a nivell global, ja que podrien representar els fonaments tècnics per a nous marcs normatius i sistemes d'incentius orientats a la millora de la prestació energètica d'edificis agrícoles controlats climàticament a través d'una estratègia de tipus top-down. / [EN] Socio-demographic trends, such as population growth and urbanization, are leading to a significant increase of the world food demand. At the same time, there is a shift of the human diet toward livestock products, vegetables, and fruit rather than cereals. Greenhouses and livestock houses can play a primary role since they can supply the necessary agricultural products with higher yields than on-field crop production and extensive animal farming. One way in which productivity is enhanced in these agricultural buildings is by a fine-tuned control of the indoor climate conditions. For this purpose, mechanical climate control systems are often adopted, but they entail a considerable energy consumption whose estimated increase may jeopardize the transition toward a sustainable agriculture. The overall objective of this thesis, hence, is to contribute to the transition toward a sustainable agriculture by improving the energy performance for climate control of greenhouses and livestock houses. To achieve this objective, a three-pronged approach was taken involving a literature review, experimental monitoring campaigns, and energy modelling activities. The literature review was performed to unpick the tangle of mutual relations between climate control and other domains of agricultural production. The nexus between energy performance and climate control was investigated analyzing real datasets acquired through monitoring campaigns performed in a greenhouse and two pig houses. This nexus was further studied adopting a numerical approach which led to the development and validation of three energy simulation models for greenhouses, broiler houses and pig houses. Each simulation model integrates the main features typical of greenhouses and livestock houses to estimate the time profiles of lumped indoor climate conditions and thermal and electrical energy consumption. The opportunities in improving the energy performance and the indoor climate conditions provided by the developed energy models were explored by analyzing specific energy-related problems. The broiler house energy model was adopted to evaluate the potentialities of a new primary energy approach for the energy-efficient envelope design of broiler houses. The same model was applied to evaluate the variation of energy consumption achieved by an improved ventilation strategy aimed at enhancing broiler welfare by reducing indoor noxious gas concentrations. This thesis contributes to the transition toward a more sustainable agriculture providing new knowledge and tools necessary for improving the energy performance for climate control of greenhouses and livestock houses. The performed analyses, in fact, quantify potential decrease of energy consumption achievable through the implementation of energy-efficient measures at both envelope -thermal insulation- and climate control system -variable angular speed fans- level. Further energy-efficient measures could be evaluated adopting the developed energy simulation models that are valuable outputs of this investigation. These models could have a positive impact at local level since stakeholders -farmers, engineers, and manufacturers- could adopt them as decision support tools for the evaluation of new technologies, strategies and solutions aimed at decreasing the overall energy consumption of greenhouses and livestock houses. These novel models represent also a robust starting point for future research in this field. Future advances may lead to the development of further calculation modules to evaluate other aspects of greenhouses and livestock houses, such as productivity variations, contaminant emissions and animal welfare. The new knowledge generated in this thesis could have positive impacts also at global level since it may represent the technical basis for new normative frameworks and incentive schemes aimed at improving the energy performance of climate-controlled agricultural buildings through a top-down approach. / Costantino, A. (2021). Improving Climate Control and Energy Performance in Greenhouses and Livestock Houses: Modelling Advances and Experimental Results [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/178457 / TESIS

Thèse produite en partenariat avec la Ferme d'hiver, centre de recherche industrielle pour l'agriculture en environnement contrôlé. / L’agriculture en environnement contrôlé (AEC) est une pratique agricole de haute technologie où la culture de plantes et son environnement sont soumis à une certaine forme de contrôle afin d’obtenir des rendements plus élevés et une efficacité de production accrue. L’AEC est essentielle en raison de son impact sur la disponibilité des terres arables, l’utilisation de l’eau et l’efficacité énergétique face à l’augmentation de l’insécurité alimentaire mondiale. Les systèmes de AEC sont contrôlés par le biais d’indicateurs de performance clés (IPC) complexes que les experts de plusieurs domaines, dont les ingénieurs et les agronomes, doivent optimiser. L’optimisation des IPC nécessite l’exploration de l’immense espace d’états du système d’AEC. Étant donné que ces systèmes sont complexes et hétérogènes, ils nécessitent une approche de modélisation et de co-simulation multi-paradigme dans laquelle les modèles utilisent les formalismes et les niveaux d’abstraction les plus appropriés. Nous proposons une architecture de co-simulation de AEC capable de capturer la dynamique des entités qui composent notre système à plusieurs niveaux d’abstraction. Nous présentons nos résultats démontrant la validité de notre approche / Controlled environment agriculture (CEA) is a high-tech agricultural practice where the crop and its environment are subject to some form of control to achieve higher yields and produc- tion efficiency. CEA is critical for its impacts on arable land availability, water usage, and energy efficiency amid the rise of global food insecurity. CEA systems are controlled through complex key performance indicators (KPI) that experts of multiple domains, including engi- neers and agronomists, must optimize. The optimization of KPI requires exploring the vast state space of the CEA system. As such systems are complex and heterogeneous, they re- quire a multi-paradigm modeling and co-simulation approach in which models use the most appropriate formalisms and levels of abstraction. We provide a co-simulation architecture for CEA to capture the dynamics of the entities that comprise our system at multiple levels of abstraction and present our results showing the validity of our approach.