36 research outputs found
Optimal (Comfortable) Operative Temperature Estimation Based on Physiological Responses of the Human Organism
Problems following the application of optimal operative temperatures estimated on the basis of PMV and the necessity to apply correct values in the new Czech Government Directive No. 523/2002 Code led to experiments based on the physiological human body response instead of solely peopleâs feelings in a given environment. On the basis of experiments on 32 subjects (university students) it has been possible to estimate: a) the total balance of hygrothermal flows between the human body and the environment, b) the optimal operative temperature as a function of the subjectâs activity, c) the thermoregulatory range for each optimal operative temperature, i.e. maximal (category Cmax) limited by the onset of sweating, minimal (category Cmin) limited by the onset of shivering (category C can be applied to naturally ventilated buildings), optimal (comfort level â category A) defined by time constant 0.368 (can be applied to air conditioned buildings), and submaximum (decreased comfort level â category B) defined by time constant 0.632 (can be applied to buildings with basic air conditioning systems).
Technique of uncertainty and sensitivity analysis for sustainable building energy systems performance calculations
Sustainable buildings design process is typical for modeling and simulation usage. The main reason is because there is generally no experience with such buildings and there is lot of new approaches and technical solutions to be used. Computer simulation could be supporting tool in engineering design process and can bring the good way for reducing energy consumption together with optimalization algorithm. For the optimization process we have to know which most sensitive input parametr from many of them has to be investigate. Therefore at first is necessary to perform the sensitivity analysis and find out the "strongest" input parametrs which most affecting the results under observation. Also still the simulation tools are mainly using to predict energy consumption, boiler and chiller loads, indoor air quality, etc. before the building is build. The information about the building envelope, schedule and HVAC components are unclear and can bring large uncertainty in results by setting this inputs to the simulation tools. Paper presents preview of uncertainty and sensitivity analysis. This techniques are shown on case study concretely BESTEST case600 with DRYCOLD climate conditions. Also systems VAV (variable volume of air) and water fancoil system are compared. For this prototype the simulation tool IES was chosen
Finite element study on bond behavior of steel bar and HSCC/HSFRCC
ABSTRACT: To study the bond behavior of steel bar and High Strength Cementitious Composites (HSCC) or High Strength Fiber Reinforced Cementitious Composites (HSFRCC), finite element simulations of Direct Tension Pull-out Bond Test (DTP-BT) are conducted. Default tensile strain softening relation in FE program ATENA is used to model HSCC. Satisfactory agreement between simulated and experimental load-displacement curve can be obtained by taking specific fracture energy of HSCC to be 50 N/m. Similar to experimental observations, tensile splitting failure is shown to be the dominate failure mode. To simulate the behavior of HSFRCC members, either the homogenization based approach (H-model) or individual crack based approach (I-model) can be employed to describe the tensile strain hardening behavior. In this paper, both approaches are first presented and discussed. Numerical results are compared to experimental results obtained in our laboratory. According to our findings, the pre-peak behavior of DTP-BT can be properly simulated by the I-model. On the other hand, H-model shows overestimation of pre-peak stiffness. Similar to HSCC, tensile splitting failure is the dominate failure mode of HSFRCC DTP-BT member. From the tests, the width of the splitting crack is wider at the surface than at the steel level. This can be explained by the numerical simulation which shows very high tensile stress at the surface of the DTP-BT specimen
IDES-EDU: Comprehensive multidisciplinary education programme to accelerate the implementation of EPBD in Europe
This paper presents a new education and training programme on integrated energy design
developed by fifteen European universities collaborating within the IDES-EDU project (2010-2013),
funded by Intelligent Energy Europe. IDES-EDU aims to accelerate the implementation of the Energy
Performance of Buildings Directive (EPBD) by proposing Master and Post Graduate education and
training in multidisciplinary teams. To speed up transition from traditional, sub-optimised building
projects with discipline-oriented, segregated budgets and operations, IDES-EDU developed
comprehensive, multidisciplinary educational programmes targetting integrated project design at the
interface of architecture and engineering. Taking into account local variations in climate,
construction and pedagogical approaches, the programme facilitates gradual implementation towards
full integration of energy efficiency in building education according to local capacity and legislation.
This paper summarises the evaluation process of the first implementation of the educational material
in the 15 universities, by academic staff, national industry and professional organisations, and
reference students from each university. Included are expected learning outcomes, level of integration
in existing curricula and alignment with theory and assessment methods. Measures for improvement
as well as further dissemination to other European educational facilities are proposed. In this manner,
the project will contribute to make the multiple opportunities for energy efficiency a reality.Intelligent Energy Europe programme for its
financial support, Grant agreement no.IEE/09/631/SI2.55822
Liberal intervention in the foreign policy thinking of Tony Blair and David Cameron
David Cameron was a critic of Tony Blairâs doctrine of the international community, which was used to justify war in Kosovo and more controversially in Iraq, suggesting caution in projecting military force abroad while in opposition. However, and in spite of making severe cuts to the defence budget, the Cameron-led Coalition government signed Britain up to a military intervention in Libya within a year of coming into office. What does this say about the place liberal interventionism occupies in contemporary British foreign policy? To answer this question, this article studies the nature of what we describe as the âbounded liberalâ tradition that has informed British foreign policy thinking since 1945, suggesting that it puts a distinctly UK national twist on conventional conservative thought about international affairs. Its components are: scepticism of grand schemes to remake the world; instinctive Atlanticism; security through collective endeavour; and anti-appeasement. We then compare and contrast the conditions for intervention set out by Tony Blair and David Cameron. We explain the similarities but crucially also the vital differences between the two leadersâ thinking on intervention, with particular reference to Cameronâs perception that Downing Street needed to loosen its control over foreign policy-making after Iraq. Our argument is that policy substance, policy style and party political dilemmas prompted Blair and Cameron to reconnect British foreign policy with its ethical roots, ingraining a bounded liberal posture to British foreign policy after the moral bankruptcy of the John Major years. This return to a patient, pragmatic and ethically informed foreign policy meant that military operations in Kosovo and Libya were undertaken in quite different circumstances, yet came to be justified by similar arguments from the two leaders
Critically evaluating collaborative research: why is it difficult to extend truth tests to reality tests?
We argue that critical evaluation achieves the reflexivity needed to facilitate collaboration by proposing boundary-negotiating artefacts to configure a joint action domain. Those objects become mediators for innovation by triggering controversies, conceived preventatively via an organized extension of what Boltanski calls âtruth testsâ to âreality testsâ so that they dynamize ongoing affairs. However, critical evaluation must also anticipate actorsâ reappropriation of boundary-negotiating artefacts in the effort to protect their rights, stakes or room for manoeuvre. Three scenarios commonly arise: avoidance or utopian projecting, enactment of inverted reality tests, and disavowal through role exchange. The article develops these propositions through the reconstruction of a modified theory-based evaluation of a collaborative research programme. The programme set out to explore how evidence from health research could be used rapidly and effectively in the context of practical problems and organizational challenges, so an internal evaluation was set up to facilitate learning during the process. What ensued, however, was a loss of trust between partners, resolved only by repositioning the evaluation as a reflective academic study, reducing its reflexive capacity to intervene on the level of activity and organizational integration. We conclude that doing successful critical evaluation and, more generally, achieving political pertinence for social scientific discourses depends on creating the conditions in which actors are able to take the risks and share the costs associated with the enhanced level of reflexivity necessary to engage in collective action as well as knowledge production
Modeling and simulation of indoor environment and building energy performance
Contemporary development of architectural engineering and building services providing building operation is related to energy supply and use. The level of building dependence on energy is given by architect's priorities during conceptual design phase. Within existing traditional buildings it is possible to predict energy and environmental performance using empirical formulas, experience and simplified models, while within modern buildings it is difficult to describe synergy performance of particular building energy systems and its impact on indoor environment quality and energy performance. For these and other cases it is possible to use numerical modelling of building energy systems and create virtual laboratory to perform experiments with the building and to optimise building design. Different viewpoints are used to classify tools for building simulation. According to the method, detail level and model purpose following classes are classified: static models, simplified dynamic models, response function models, numerical methods models, analogy with electrical circuits and CFD (computational fluid dynamics) models. Keywords: performance simulation, low-energy building
Intelligent Building Control System for EPBD Certification Support
Building commissioning is a developing concept also in the Czech Republic. At present time only some aspects of building commissioning are implemented as a part of the facility management and energy auditing processes that are related to EPBD implementation. The project, presented in this paper, aims to find ways of energy-efficient operation of existing and designed energy- efficient buildings and is based on the fact that many buildings designed according to modern principles, in its operation does not behave as expected. The project is investigating and developing procedures to help change the current often intuitive approach to operate buildings in a systematic activity, taking into account energy conservation. Modern control systems of intelligent HVAC buildings could provide not only the information needed for the operational control of building, but also to detect faults and to evaluate the energy performance of the building. Under the IEA Annex 47 project, authors started to develop tools that support additional aspects of the commissioning process, including new control system for building energy services. The paper is focused on specification of new function of building control system, providing information for existing building EPBD certification. Results in terms of implementation of this function into existing building energy control system are discussed