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71.
This paper presents monitoring results of two examples of building integrated PV system investigated at the School of the Built Environment, University of Nottingham in the UK. One of the systems is installed on an educational building, and consists of a thin film PV façade appropriate for commercial or office suites. The other system is installed on a detached house, and uses crystalline PV roof slates, appropriate for domestic buildings. As the two buildings are significantly different in size, construction and occupancy, the design and selection of the PV system for each was also different. The monitoring investigation has assisted identification of shortfalls in performance and possible explanations have been suggested. The results presented in this paper provide information on the design process, and highlight similarities and differences in the design, installation, performance and economics of the two systems. 相似文献
72.
In this study, the change in the load-bearing system cost of a reinforced concrete office building has been investigated in relation to the earthquake regions and soil types. Three different office projects each with five stories were investigated. The structural design calculations have been made according to four different soil types and four different earthquake regions. According to each combination, concrete, steel and formwork adopted approximations were calculated to reach the rough cost of each office building. The changes in the cost of projects according to the soil type and earthquake region were examined with multiple regression analysis and analysis of variance. In general, the change in cost has been observed around 22% between first and fourth soil type and 14% between first and fourth earthquake region. 相似文献
73.
Zohar Yosibash Netta Omer Martin Costabel Monique Dauge 《International Journal of Fracture》2005,136(1-4):37-73
The solution to elastic isotropic problems in three-dimensional (3-D) polyhedral domains in the vicinity of an edge is provided
in an explicit form. It involves a family of eigen-functions with their shadows, and the associated edge stress intensity
functions (ESIFs), which are functions along the edges. Utilizing the explicit structure of the solution in the vicinity of
the edge we use the quasidual function method, recently presented in [Omer et al. (2004). International Journal of Fracture 129:97–130] for scalar elliptic problems and in [Costabel et al. (2004). SIAM Journal of Mathematical Analysis 35(5), 1177–1202] in a general theoretical framework, for the extraction of ESIFs. This method provides a polynomial approximation
of the ESIF along the edge whose order is adaptively increased so to approximate the exact ESIF. It is implemented as a post-solution
operation in conjunction with the p-version finite element method. Numerical examples are provided in which we extract ESIFs associated with traction free or
homogeneous Dirichlet boundary conditions in 3-D cracked domains or 3-D V-Notched domains. These demonstrate the efficiency,
robustness and high accuracy of the proposed quasi-dual function method. 相似文献
74.
Omer Van der Biest 《材料科学技术学报》2011,27(8):729-734
Diffusion couples, Fe-6.8 wt% Al-1.0 wt% Si/Fe and Fe-6.3 wt% Al-0.9 wt% Si/Fe were constructed and separately annealed at 1050°C for 3 h and at 1000°C for 64 h. The concentration profiles of Fe, Al and Si atoms in these couples were measured by electron probe micro-analysis (EPMA), while the diffusion behavior was also simulated by coupling thermodynamic and kinetic properties of Fe-Al-Si system. The simulation results were in good agreement with the measured concentration profiles showing the validity of dynamic parameters of Fe-Al-Si system. Calculation was made for Fe-7 wt% Al-1 wt% Si/Fe diffusion couples at 1000?C with different diffusion time. Silicon uphill was found under the influence of aluminum. 相似文献
75.
In this study, the first and the second law of thermodynamics are used to analyze the performance of a single-stage water-lithium bromide absorption refrigeration system (ARS) when some working parameters are varied. A mathematical model based on the exergy method is introduced to evaluate the system performance, exergy loss of each component and total exergy loss of all the system components. Parameters connected with performance of the cycle–circulation ratio (CR), coefficient of performance (COP), Carnot coefficient of performance (COPc), exergetic efficiency (ξ) and efficiency ratio (τ)–are calculated from the thermodynamic properties of the working fluids at various operating conditions. Using the developed model, the effect of main system temperatures on the performance parameters of the system, irreversibilities in the thermal process and non-dimensional exergy loss of each component are analyzed in detail. The results show that the performance of the ARS increases with increasing generator and evaporator temperatures, but decreases with increasing condenser and absorber temperatures. Exergy losses in the expansion valves, pump and heat exchangers, especially refrigerant heat exchanger, are small compared to other components. The highest exergy loss occurs in the generator regardless of operating conditions, which therefore makes the generator the most important component of the cycle. 相似文献
76.
Levent Tutluoglu Cigdem Keles 《International Journal of Rock Mechanics and Mining Sciences》2011,48(8):1248-1261
A new method called the straight notched disk bending method is developed for mode I fracture toughness determination using rock cores. Disk specimens of andesite and marble having a single straight edge notch were subjected to three-point bending loads. Dimensionless stress intensity factor estimations and fracture toughness tests were conducted for different notch lengths, span lengths, thicknesses and diameters of the cylindrical rock specimens. Stress intensity factors were computed by three-dimensional finite element modeling and the results were presented for a wide range of specimen geometrical parameters. Results of experiments were compared to the results of well-known mode I fracture toughness testing methods. For specimens having thickness equal to the radius, mode I fracture toughness was lower and close to the results obtained by semi-circular bending method. When thickness was increased and doubled, mode I fracture toughness increased and approached to the value found by the suggested cracked chevron notched Brazilian disk method. Advantages of the new method included easy specimen preparation and testing procedure, stiffer specimen geometry, smaller fracture process zone, and flexibility of the specimen geometry for the investigation of the size effect behavior. 相似文献
77.
北地里,千宅万户的屋梁受尽风欺雪压犹自温柔地抱着一团小小的燕巢。这是最温情的守候。人世间,千秋万代的屋梁穷尽一生之力,默默擎起身下各异的居所。这是最无私的担当。可古往今来,自喻有情的世人皆赞梁间燕,梁 相似文献
78.
79.
Therapeutic empathy is described as an active narrative process, in which the therapist attempts to construe and express the inner emotional logic of the client's problem patterns. The empathic narrative is contrasted to the external narrative, which describes the client from the outside and the client's behavior as making sense from the point of view of the theory rather than from that of the client's. The criterion of an empathic narrative is that it elicits from the client the response "That's me!" The external narrative, in distinction, fails to elicit this self-recognition. The persistent rejection of the therapist's formulations by the client and the ensuing state of therapeutic impasse is interpreted as being often due to the therapist's assumption that the client should accept an external narrative as if it were an empathic one. When such a situation develops, the therapist may overcome the impasse by acknowledging the externality of the previous therapeutic narrative and proposing a potentially empathic one in its stead. Three case examples of a 49-yr-old married woman, a teenage girl, and 28-yr-old single male are presented to demonstrate narrative empathy within the therapeutic context. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
The life-sketch is a highly condensed psychobiography designed to focus and shorten therapy that has recently emerged at different points across the spectrum of therapeutic approaches. It reflects a growing view of psychotherapy as a re-narration of the client's life story. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献