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The construction industry is considered as one of the least productive, highest energy consuming, and least digitized industries. The Lean Management (LM) philosophy became a significant way for eliminating non-value-added activities and wastes during a building’s lifecycle. However, studies have shown that philosophies are not efficient by themselves to solve the issues of the construction industry. They need to be supported with the appropriate technologies and tools. Therefore, the integrated use of Building Information Modelling (BIM) with LM or Value Engineering (VE) were proposed in the literature. Nonetheless, it was also seen that BIM can provide more insights and improvements when BIM is integrated with data analysis tools to analyze BIM data. In the literature, the synergies between these concepts are generally addressed pairwise, and there is no comprehensive framework which identifies their relationships. Therefore, this study aims to develop a maturity framework that facilitates the adoption of LM, VE, BIM, and Big Data Analytic (BDA) concepts to address long-standing productivity and digitalization issues in the Architecture, Engineering, and Construction (AEC) industry. Design Science Research (DSR) methodology and its three-cycle view (relevance, rigor, and design cycle) were applied to build the proposed maturity framework. Two interviews were performed to identify and observe research problem in relevance cycle. In the rigor cycle, a comprehensive literature review was performed to create a base for the development of the maturity framework. In addition to the developed base of the framework, lean processes were added to this cycle. In the design cycle, the developed framework was evaluated and validated by five experts through face-to-face interviews. The importance of employer’s requirements to adopt the proposed methodologies, the negative impact of change orders, the importance of pre-construction phases to facilitate value creation and waste elimination, and the usage of common data environment with BIM were identified as the prominent application and adaptation issues.

Abstract The rapidly growing construction industry has accelerated water and energy scarcity in China, threatening its sustainable development. This study integrates multi-regional input-output (MRIO) and data envelopment analysis (DEA) to investigate the water-energy nexus in the construction industry at the provincial level through the entire industrial supply chain. Results show that the construction industry accounts for 8.97% and 27.20% of virtual water and embodied energy in China, respectively. The western area experiences the most energy- and water-intensive construction processes given its backward economy and outdated technological development. The northern area faces great challenges with regard to energy intensity improvements, whereas the central regions suffer from large pressure relating to inefficient water use. The manufacture of non-metallic mineral products, smelting, and the pressing of metals are the largest suppliers of virtual water and embodied energy. The efficiency assessment results demonstrate that Jiangsu and Zhejiang are two DEA-effective regions. China has achieved a relatively high level of scale efficiency but suffers from backward technology.

Spatial planning has to deal with trade-offs between various stakeholders’ wishes and needs as part of planning and management of landscapes, natural resources and/or biodiversity. To make ecosystem services (ES) trade-off research more relevant for spatial planning, we propose an analytical framework,which puts stakeholders, their land-use/management choices, their impact on ES and responses at the centre. Based on 24 cases from around the world, we used this framing to analyse the appearance and diversity of real-world ES trade-offs. They cover a wide range of trade-offs related to ecosystem use, including: land-use change, management regimes, technical versus nature-based solutions, natural resource use, and management of species. The ES trade-offs studied featured a complexity that was far greater than what is often described in the ES literature. Influential users and context setters are at the core of the trade-off decision-making, but most of the impact is felt by non-influential users. Provisioning and cultural ES were the most targeted in the studied trade-offs, but regulating ES were the most impacted. Stakeholders’ characteristics, such as influence, impact faced, and concerns can partially explain their position and response in relation to trade-offs. Based on the research findings, we formulate recommendations for spatial planning.

Die Doktorarbeit studiert unendliche Ensembles gewöhnlicher Differentialgleichungen mit gemeinsamen Monotonieeigenschaften, wie sie in der Nachhaltigkeitsforschung auftreten. Es werden neue Verfahren zur Behandlung von solchen Ensembles entwickelt und zur modellgestützen analyse verschiedener Problemen des nachhaltigen Umgangs mit natürlichen Ressourcen erprobt. Qualitative Differentialgleichungen (QDEs) und Differentialinklusionen werden in den neu formalisierten Rahmen der Modellensembles eingebettet. Darunter versteht man eine Menge von Funktionen auf einem Zustandsraum, die Anfangswertprobleme definieren. Für eine QDE schreibt man eine Matrix von Vorzeichen vor und erhält als Modellensemble die Menge aller Funktionen, bei denen die Einträge der Jacobimatrix dem Vorzeichen nach der vorgeschriebenen Matrix entsprechen. Angewendet werden die neuen Methoden auf die Armuts- Degradations-Spirale in Entwicklungsländern, Fischereimanagement (insbesondere industrialisierte Hochseefischerei und partizipatorische Managementansätze), sowie Wassermanagement zur Vermeidung von Eutrophierung. Derartige Anwendung stellen besondere anforderungen an die Modellierung, insbesondere Unsicherheiten im Wissen und der Bedarf nach verallgemeinerbaren Resultaten. Es wird gezeigt, dass Modellensembles hierfür geeignet sind. Basierend auf der neu eingeführten graphentheoretischen Formulierung von QDEs werden vier innovative Verfahren zum Umgang mit großen QDEs entwickelt. Hierbei wird die Viabilitätstheorie begrifflich wie methodisch für Abstraktions- und Restriktionsverfahren eingesetzt. (i) Die graphentheoretische Fassung viabler Mengen führt zur No-return Abstraktion, die einen engen Bezug zu starken Zusammenhangskomponenten aufweist. Damit lassen sich Zustandsgraphen aggregiert darstellen und bezüglich Nachhaltigkeitsfragen evaluieren. (ii) Die Restriktion der zulässigen Lösungen erlaubt es, Kanten von untergeordneter Bedeutung aus dem Zustandsgraphen zu eliminieren. (iii) Die Restriktion auf Systeme, bei denen die Einträge der Jacobimatrix eine vorgegebene partielle Ordnung aufweisen, ermöglicht die Elimination weiterer Pfade. (iv) Zuletzt werden Intervallschranken für die Einträge der Jacobimatrix berücksichtigt. Die Anwendungen zeigen, dass mit diesen Methoden neue und robuste Eigenschaften auch sehr allgemeiner Modelle zum Management natürlicher Ressourcen gewonnen werden können. Ihre Stärken für den Entwurf alternativen Politikoptionen werden deutlich. The thesis studies infinite ensembles of ordinary differential equations with common monotonicity properties as they typically appear in sustainability research. New methods to process such ensembles are developed and applied for the model-based analysis of different sustainable resource use problems. Qualitative differential equations (QDEs) and differential inclusions are embedded into the new formal framework of model ensembles. A model ensemble is defined as a set of functions on a state space which specify initial value problems. For a QDE a matrix of signs is prescribed, and the model ensemble is the set of all functions where the coefficients of the Jacobian have the same signs as the coefficients of the prescribed matrix. The new methods are applied to the impoverishment-degradation spiral in developing countries, to fisheries management (in particular industrialised deep-sea fishery and participatory management), and to water management to avoid eutrophication. These applications pose special challenges for modelling, in particular knowledge uncertainties and the demand for generalisable results. It is shown that model ensembles are adequate for these challenges. Based on a new graph theoretical formulation of QDEs, four innovative techniques for the analysis of large QDEs are developed. For that, viability theory is used conceptually and methodologically for abstraction and restriction techniques. (i) The graph theoretical formulation of viable sets leads to the no-return abstraction, which is closely related to strongly connected components. This makes it possible to display large state-transition graphs in an aggregated way and to evaluate them with respect to sustainability criteria. (ii) By restricting the set of admissible solutions, edges with limited relevance can be eliminated from the state-transition graph. (iii) By restricting the model ensemble to systems where the coefficients of the Jacobian have a prescribed partial order, further paths can be eliminated. (iv) Finally, interval bounds for the coefficients of the Jacobian are considered. The applications show that the new methods strongly improve the identification of new and robust properties of very general models about the management of natural resources. Their advantages for the design of alternative policy options become clear. Front Matter: Title page, Preface, Contents, Notations and Concepts 1\. Introduction 2\. Qualitative Reasoning with Model Ensembles 2.1 Model Ensembles and Set-Valued Solution Operators 2.2 Qualitative Differential Equations 2.3 Differential Inclusions 2.4 Viability Theory 3\. Abstraction and Restriction Techniques 3.1 No-Return Abstraction 3.2 Marginal Edges 3.3 Ordinal Assumptions 3.4 Quantitative Bounds 4\. Management of Natural Resources 4.1 Land-Use Changes in Developing Countries 4.2 Capital Accumulation in Unregulated Fisheries 4.3 Participatory Fishery Management 4.4 Lake Management 5\. Conclusions Annex: Model Code Back Matter: Bibliography, Lebenslauf, Zusammenfassung

AbstractOwing to the increasing challenges of climate change and limited resources, a bundle of requirements for bioenergy are given, such as securing the energy supply, linking with the material use of biomass, or producing negative emissions. Smart bioenergy generation and utilization can fulfil those requirements by the sustainable, efficient, and flexible provision of renewable energy. This study aims to thoroughly define and structure all contributions bioenergy can make to the energy system, in the form of a comprehensive multilevel goal and indicator system. The built system includes several levels of subgoals associated with biomass, with technology, and its integration. The goal system was verified by research project leaders and further experts and can be applied to any bioenergy concept worldwide.

Lacking recyclability of multilayer packaging can be overcome by using a thermoreversible crosslinking adhesive consisting of maleimide- and furan-functionalized polyurethane-(PU-)prepolymers, reacting in a Diels–Alder-reaction. Here, the furan-functionalized PU-prepolymer carries furan-side-chains to avoid the usage of an additional crosslinking agent. Thus, N‑(2‑hydroxyethyl)maleimide and furfurylamine are the only two chemicals contained in the adhesive that are not listed in the appendix of EU Regulation 10/2011. Using migration modelling, it could be shown that, at 23 °C, both chemicals have lag-times of only a few minutes if 45 µm PE is used as a barrier. However, if the residual content is below 30 mg/kg, the legally specified maximum amount of 0.01 mg/kg food is not reached. After determining the diffusion coefficients and the activation energy of diffusion through ethylene-vinyl alcohol copolymer (EVOH), it could be determined that the lag-time of the migrants can be extended to at least 9 years by the use of 3 µm EVOH. From a food law point of view, the use of the described adhesive is possible if the above‑mentioned measures are complied.