In addition to material, spatial and thermal standards and norms that influence the resource intensity of home environments, a key indicator of the environmental impact related to housing is found in residents’ ways of life. Of interest to the study presented in this paper is how residents’ perceptions of home and living standards relate to opinions on environmental issues and the reduction of resource use, exploring the potential and willingness to engage in low-impact ways of living. Empirical material from a questionnaire (n = 156) and interview study (n = 22) with residents in a tenant-owned housing association in Sweden provides insights into conventions and perceptions surrounding practices primarily linked to voluntary simplicity, living smaller as well as sharing spaces and resources. The study emphasizes the need for understanding residents’ perspectives and the implications this might have for targeting the resource intensity of homes in future development and policy. 相似文献
Architects are a professional group that is commonly associated with creative and aesthetic work and with strong professional norms, values and identities. While such shared norms and beliefs are positive overall in terms of being constitutive of professional subject‐positions, an overemphasis on specific skills and qualities may also be regarded as a burden on members of the professional community. A study of a major Scandinavian architect office suggests that the perceived lack of creative and innovative thinking and accompanying dialogues and discussions among practising architects tends to produce cynicism and, to some extent, disappointment. As a consequence, professional ideologies may in some cases be out of joint with everyday work realities, and thereby to some extent produce expectations that are complicated to fulfil. Professional ideologies are thus both what integrates and consolidates a profession while at the same time prescribing ideal future scenarios for the professional community. 相似文献
A four-dimensional mapping (three spatial dimensions + time) of myocardial strain-rate would help to describe the mechanical properties of the myocardium, which affect important physiological factors such as the pumping performance of the ventricles. Strain-rate represents the local instantaneous deformation of the myocardium and can be calculated from the spatial gradients of the velocity field. Strain-rate has previously been calculated using one-dimensional (ultrasound) or two-dimensional (2-D) magnetic resonance imaging) techniques. However, this assumes that myocardial motion only occurs in one direction or in one plane, respectively. This paper presents a method for calculation of the time-resolved three-dimensional (3-D) strain-rate tensor using velocity vector information in a 3-D spatial grid during the whole cardiac cycle. The strain-rate tensor provides full information of both magnitude and direction of the instantaneous deformation of the myocardium. A method for visualization of the full 3-D tensor is also suggested. The tensors are visualized using ellipsoids, which display the principal directions of strain-rate and the ratio between strain-rate magnitude in each direction. The presented method reveals the principal strain-rate directions without a priori knowledge of myocardial motion directions. 相似文献
A performance-based service life design format based on climatic exposure on one hand and “resistance” of materials against mould growth on the other hand, is presented in this paper. A limit state for onset of mould growth is defined as the occurrence of traces of mould observed by microscopy. A dose–response model is proposed by which onset of mould growth can be predicted for an arbitrary climate history of combined relative humidity ? and temperature T. The model is calibrated and verified against a comprehensive set of experimental data published by Viitanen et al. [Viitanen H, Ritschkoff A-C. Mould growth in pine and spruce sapwood in relation to air humidity and temperature. Uppsala: Swedish University of Agricultural Sciences, Department of Forest Products; 1991. Report No. 221, 49 p.; Viitanen H. Modelling the time factor in the development of mould fungi – effect of critical humidity and temperature conditions in pine and spruce sapwood. Holzforschung 1997;51(1):6–14; Viitanen H. Modelling the time factor in the development of brown rot decay in pine and spruce sapwood – the effect of critical humidity and temperature conditions. Holzforschung 1997;51(2):99–106; Viitanen H, Bjurman J. Mould growth on wood under fluctuating humidity conditions. Material und Organismen 1995;29(1):27–46] describing mould development on spruce and pine sapwood as a function of climatic exposure. The model is applied to predict time to onset of mould growth under natural outdoor climate (under shelter) as well as mould development in building attics and in crawl space foundations. The predicted response shows reasonable agreement with experimental observations and proven experience, although biological processes of this type display great variability. The results show that a generally applicable, quantitative model can be used as a powerful tool for moisture safe design in practice. The model is designed to facilitate continuous improvement of prediction capability by further laboratory testing of various materials under specified climate conditions. In combination with currently available building physics software the model is suitable for moisture safe design of wood-based components in the building envelope. 相似文献
Tissue engineering with chondrogenic cell based therapies is an expanding field with the intention of treating cartilage defects. It has been suggested that scaffolds used in cartilage tissue engineering influence cellular behavior and thus the long-term clinical outcome. The objective of this study was to assess whether chondrocyte attachment, proliferation and post-expansion re-differentiation could be influenced by the size of the fibers presented to the cells in a scaffold. Polylactic acid (PLA) scaffolds with different fiber morphologies were produced, i.e. microfiber (MS) scaffolds as well as nanofiber-coated microfiber scaffold (NMS). Adult human articular chondrocytes were cultured in the scaffolds in vitro up to 28 days, and the resulting constructs were assessed histologically, immunohistochemically, and biochemically. Attachment of cells and serum proteins to the scaffolds was affected by the architecture. The results point toward nano-patterning onto the microfibers influencing proliferation of the chondrocytes, and the overall 3D environment having a greater influence on the re-differentiation. In the efforts of finding the optimal scaffold for cartilage tissue engineering, studies as the current contribute to the knowledge of how to affect and control chondrocytes behavior. 相似文献
Building on a practice-oriented approach and the theoretical construct of institutional work, the organizational nexus of changing practices for public facilities management is conceptualized in a multi-level framework. To support the conceptual framework, changing management practices are illustrated with the help of real-life experiences gained in a case study of a strategy project in a Swedish public construction client organization with the goal of developing a strategic facilities plan. These real-life examples, captured through interviews and field observations, cohere with the research method of narrative inquiry. The framework envisions projective agencies of various actors, both human and non-human (objects), in change processes. Findings show how key actors, through collaborative co-creation processes, take different complementary roles when promoting new practices into a specific organizational setting. By jointly promoting a set of preferred arrangements they establish proto-institutions. In addition, various objects were attributed rhetorical agency to support new public FM practices in that these served as purposeful non-human actors, triggering and legitimizing actions taken. With focus on emerging institutions in the making and especially projective agencies for institutional change, this research contributes to furthered layered understandings on institutional work related to change in construction in general and specifically in public sustainable facilities management. 相似文献
The NOx storage performance at low temperature (100–200 °C) has been studied for model NOx storage catalysts. The catalysts were prepared by sequentially depositing support, metal oxide and platinum on ceramic monoliths. The support material consisted of acidic aluminium silicate, alumina or basic aluminium magnesium oxide, and the added metal oxide was either ceria or barium oxide. The NOx conversion was evaluated under net-oxidising conditions with transients between lean and rich gas composition and the NOx storage performance was studied by isothermal adsorption of NO2 followed by temperature programmed desorption of adsorbed species. The maximum in NOx storage capacity was observed at 100 °C for all samples studied. The Pt/BaO/Al2O3 catalyst stored about twice the amount of NOx compared with the Pt/Al2O3 and Pt/CeO2/Al2O3 samples. The storage capacity increased with increasing basicity of the support material, i.e. Pt/Al2O3 · SiO2 < Pt/Al2O3 < Pt/Al2O3 · MgO. Water did not significantly affect the NOx storage performance for Pt/Al2O3 or Pt/BaO/Al2O3.