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Earlier studies assume that historical dwellings and post-war dwellings in particular, are less sustainable than modern dwellings, justifying its demolition. Over time, historical buildings have been transformed and their energy performance improved. However, there is little known on the energy performance of historical dwellings. The purpose of this paper is to unveil the role of historical dwellings and its transformations in improving urban sustainability.

In this research, historical dwellings (built=1970) are distinguished in listed and unlisted dwellings. Three cities were selected as case study – Amsterdam, The Hague and Rotterdam – and three post-war neighborhoods – New-West, Mariahoeve and Ommoord. This research uses the difference in energy label (original vs current performance) to discuss the transformations of dwellings: comparing modern and historical; post-war and other historical; and listed and unlisted dwellings.

Findings reveal that historical and post-war dwellings have great potentials to raise the energy performance e.g. by applying after insulation and renewable energy sources. Furthermore, The Hague and its post-war neighborhood Mariahoeve have a considerably lower energy performance. Further research could relate the raising of energy performance to the cultural significance of such dwellings, to better discuss the role of attributes and their transformation to raising energy performance.

This paper addresses the knowledge gap of the current energy performance of historical dwellings, by presenting and discussing its role in improving urban sustainability.

The purpose of this work is to apply a recently proposed constitutive model for mechanically induced martensitic transformations to the prediction of transformation loci. Additionally, this study aims to elucidate if a stress-assisted criterion can account for transformations in the so-called strain-induced regime.

The model is derived by generalising the stress-based criterion of Patel and Cohen (1953), relying on lattice information obtained using the Phenomenological Theory of Martensite Crystallography. Transformation multipliers (cf. plastic multipliers) are introduced, from which the martensite volume fraction evolution ensues. The associated transformation functions provide a variant selection mechanism. Austenite plasticity follows a classical single crystal formulation, to account for transformations in the strain-induced regime. The resulting model is incorporated into a fully implicit RVE-based computational homogenisation finite element code.

Results show good agreement with experimental data for a meta-stable austenitic stainless steel. In particular, the transformation locus is well reproduced, even in a material with considerable slip plasticity at the martensite onset, corroborating the hypothesis that an energy-based criterion can account for transformations in both stress-assisted and strain-induced regimes.

A recently developed constitutive model for mechanically induced martensitic transformations is further assessed and validated. Its formulation is fundamentally based on a physical metallurgical mechanism and derived in a thermodynamically consistent way, inheriting a consistent mechanical dissipation. This model draws on a reduced number of phenomenological elements and is a step towards the fully predictive modelling of materials that exhibit such phenomena.

This paper aims to explain and discuss the complex nature and value of knowledge as an exploitable resource for business.

The authors propose a conceptual explanation of knowledge based on three pillars: the plurality of its nature, understood to be conservative, multipliable and generative, its contextual value and the duality of carrier incorporating business knowledge, objects or processes. After conceptualizing the nature of knowledge, the authors offer a metaphor based on the classic transformation from “potential” to “kinetic” energy in an inclined plane assuming that the conservative nature of knowledge makes it act as energy.

The metaphor uses the concept of potential and kinetic energy: if energy is only potential, it has a potential value not yet effective, whereas if the potential energy (knowledge) becomes kinetic energy (products and/or services), it generates business value. In addition, business value is a function of the speed acquired and caused by the angle of inclined plan, namely, the company’s business model. Knowledge is the source of the value and can be maintained and regenerated only through continuous investments. Several years later the value extraction reaches a null value of the company (potential energy) which will cease to act (kinetic energy) for triggering both the value generated and the value extracted.

The paper proposes an initial attempt to explain the meaning of the transformation of knowledge using a metaphor derived from physics. The metaphor of the energy of knowledge clearly depicts the managerial dilemma of balancing a company’s resources for both the generating and extracting value. Similarly, future study should try to associate other knowledge peculiarities to physical phenomena.

The purpose of this paper is to examine the knowledge dynamics process based on the energy metaphor and the thermodynamics framework. Knowledge dynamics is analyzed as a transformational process that goes beyond the Newtonian logic used to date.

The research design is based on metaphorical thinking, critical analysis of the mostly used knowledge metaphors to date, and the logic of thermodynamics, which is the science of energy transformation.

Knowledge is conceived as a field, composed of three fundamental forms: rational knowledge, emotional knowledge and spiritual knowledge. Each form of knowledge can be transformed into another form, thus generating an iterative and interactive dynamics. The unity of knowledge is supported by the brain’s organic structure.

Understanding knowledge dynamics as a transformational process helps managers in their problem-solving and implementation of strategies in their organizations. Knowledge dynamics is fundamental to the learning and unlearning processes, and for stimulating innovation. Knowledge dynamics, as a transformational process, is influencing both organizational behavior as well as consumers’ behavior.

The present research uses for the first time a thermodynamics approach in understanding and explaining the knowledge dynamics, which is a transformational process of three fundamental forms of knowledge: rational, emotional and spiritual.

Hydrogen fuel cells could play an important role in meeting the challenges of the Two Degrees Scenario. The purpose of this paper is to review the development of this technology in South Africa with the aim of understanding how the country can transform its existing socio-technical systems and act to support a hydrogen-based technological innovation system (TIS).

A mixed methods approach has been followed in this study. Secondary data analysis was used initially to build a profile of South Africa’s present energy system, followed by a stakeholder survey of the emerging hydrogen economy. Respondents were selected based on a convenience/snowball sampling approach and were interviewed using a semi-structured questionnaire, covering opportunities for South Africa in the global hydrogen economy; sources of competitive advantage; the present phase of development; the maturity of each function and the main weaknesses within the TIS; and finally the appropriate policy instrument to remedy the weakness and/or maximise opportunities for local companies.

The research has shown that the hydrogen economy is still at a pre-competitive level and requires ongoing government support to ensure an energy transition is realised. In particular, it is important that niche experimentation, a proven strategy in respect of successful sustainability transitions, is further pursued. Importantly, the net cost of hydrogen-based transportation, which is still several times larger than the cost of transport based on the internal combustion engine (ICE), must be reduced, especially in the key applications of public transport and underground vehicles. Furthermore, the development of digital technologies to manage supply fluctuations in energy grids must be accelerated.

The South Africa economy will be severely affected by the replacement of the ICEs with battery electric vehicles due to the country’s reliance on ICEs for platinum demand. Fuel cells represent a new market for platinum but the hydrogen TIS is still at a vulnerable point in its development; without policy support, it will not contribute to a successful socio-technical transformation, nor provide an alternative outlet for platinum.

ONE of tin: most important causes of low efficiency in duel systems is tin; large loss which accompanies a transformation from kinetic energy to pressure. The exit cones of wind tunnels and turbines and the expanding entries to cooling duets and air‐intakes on aircraft are some of the duct systems which lvcpiirc ellicient expansions of the flow.

Bioenergy is a key component of climate change mitigation strategies aiming at low stabilization. Its versatility and capacity to generate negative emissions when combined with carbon capture and storage add degrees of freedom to the timing of emission reductions. This paper aims to explore the robustness of a bioenergy-based mitigation strategy by addressing several dimensions of uncertainty on biomass potential, bioenergy use and induced land use change emissions.

Different mitigation scenarios were explored by two different energy-economy optimization models coupled to the same land use model, which provides a common basis for the second generation bioenergy dynamics in the two energy-economy models.

Using bioenergy is found to be a robust mitigation strategy as demonstrated by high biomass shares in primary energy demand in both models and in all mitigation scenarios.

A variety of possible storylines about future uses of biomass exist. The comparison of the technology choices preferred by the applied models helps understand how future emission reductions can be achieved under alternative storylines.

The presented comparison-based assessment goes beyond other comparison studies because both energy-economy models are coupled to the same land use model.

The paper's aim is to suggest a new micro‐thermonuclear reactor for aerospace.

Methods of the thermonuclear physics are used for the research.

The result is new micro‐thermonuclear reactor with very small fuel pellet that uses plasma confinement generated by multi‐reflection of laser beam or its own magnetic field. The Lawson criterion increases by hundreds of times. The author also suggests a new method of heating the power‐making fuel pellet by outer electric current as well as new direct method of transformation of ion kinetic energy into harvestable electricity. These offered innovations dramatically decrease the size, weight and cost of thermonuclear reactor, installation, propulsion system and electric generator.

The author is researching the efficiency of these innovations for two types of the micro‐thermonuclear reactors: multi‐reflection reactor (inertial confinement fusion) and self‐magnetic reactor (magnetic confinement fusion).

The author offers several innovations. Results may be used for the design of thermonuclear aerospace engines, propulsion and electric generators.

The 1899 book and the 1939 MGM film The Wizard of Oz hold a permanent influence on US culture. In this article we describe how the Wizard of Oz’s story can serve as a metaphor for balancing energies and organizational transformation at all levels. Just as the spiritual transformation of a person must be initiated from within, so organizations must discover the inner power to balance energies and transform themselves into more humane systems.