A model for the sustainable selection of building envelope assemblies

Energy Technology Data Exchange (ETDEWEB)

Huedo, Patricia, E-mail: huedo@uji.es [Universitat Jaume I (Spain); Mulet, Elena, E-mail: emulet@uji.es [Universitat Jaume I (Spain); López-Mesa, Belinda, E-mail: belinda@unizar.es [Universidad de Zaragoza (Spain)

2016-02-15

The aim of this article is to define an evaluation model for the environmental impacts of building envelopes to support planners in the early phases of materials selection. The model is intended to estimate environmental impacts for different combinations of building envelope assemblies based on scientifically recognised sustainability indicators. These indicators will increase the amount of information that existing catalogues show to support planners in the selection of building assemblies. To define the model, first the environmental indicators were selected based on the specific aims of the intended sustainability assessment. Then, a simplified LCA methodology was developed to estimate the impacts applicable to three types of dwellings considering different envelope assemblies, building orientations and climate zones. This methodology takes into account the manufacturing, installation, maintenance and use phases of the building. Finally, the model was validated and a matrix in Excel was created as implementation of the model. - Highlights: • Method to assess the envelope impacts based on a simplified LCA • To be used at an earlier phase than the existing methods in a simple way. • It assigns a score by means of known sustainability indicators. • It estimates data about the embodied and operating environmental impacts. • It compares the investment costs with the costs of the consumed energy.

A model for the sustainable selection of building envelope assemblies

International Nuclear Information System (INIS)

Huedo, Patricia; Mulet, Elena; López-Mesa, Belinda

2016-01-01

The aim of this article is to define an evaluation model for the environmental impacts of building envelopes to support planners in the early phases of materials selection. The model is intended to estimate environmental impacts for different combinations of building envelope assemblies based on scientifically recognised sustainability indicators. These indicators will increase the amount of information that existing catalogues show to support planners in the selection of building assemblies. To define the model, first the environmental indicators were selected based on the specific aims of the intended sustainability assessment. Then, a simplified LCA methodology was developed to estimate the impacts applicable to three types of dwellings considering different envelope assemblies, building orientations and climate zones. This methodology takes into account the manufacturing, installation, maintenance and use phases of the building. Finally, the model was validated and a matrix in Excel was created as implementation of the model. - Highlights: • Method to assess the envelope impacts based on a simplified LCA • To be used at an earlier phase than the existing methods in a simple way. • It assigns a score by means of known sustainability indicators. • It estimates data about the embodied and operating environmental impacts. • It compares the investment costs with the costs of the consumed energy.

Implementation of Models for Building Envelope Air Flow Fields in a Whole Building Hygrothermal Simulation Tool

DEFF Research Database (Denmark)

Sørensen, Karl Grau; Rode, Carsten

2009-01-01

cavity such as behind the exterior cladding of a building envelope, i.e. a flow which is parallel to the construction plane. (2) Infiltration/exfiltration of air through the building envelope, i.e. a flow which is perpendicular to the constructionplane. The paper presents the models and how they have...

Interior thermal insulation systems for historical building envelopes

Science.gov (United States)

Jerman, Miloš; Solař, Miloš; Černý, Robert

2017-11-01

The design specifics of interior thermal insulation systems applied for historical building envelopes are described. The vapor-tight systems and systems based on capillary thermal insulation materials are taken into account as two basic options differing in building-physical considerations. The possibilities of hygrothermal analysis of renovated historical envelopes including laboratory methods, computer simulation techniques, and in-situ tests are discussed. It is concluded that the application of computational models for hygrothermal assessment of interior thermal insulation systems should always be performed with a particular care. On one hand, they present a very effective tool for both service life assessment and possible planning of subsequent reconstructions. On the other, the hygrothermal analysis of any historical building can involve quite a few potential uncertainties which may affect negatively the accuracy of obtained results.

Study of an experimental methodology for thermal properties diagnostic of building envelop

OpenAIRE

Yang , Yingying; Sempey , Alain; Vogt Wu , Tingting; Sommier , Alain; Dumoulin , Jean; Batsale , Jean ,

2017-01-01

International audience; The building envelope plays a critical role in determining levels of comfort and building efficiency. Its real thermal properties characterization is of major interest to be able to diagnose energy efficiency performance of buildings (new construction and retrofitted existing old building). Research and development on a possible methodology for energy diagnostic of the building envelop is a hot topic and necessary trend. Many kinds of sensors and instruments are used f...

Multiobjective optimization design of green building envelope material using a non-dominated sorting genetic algorithm

International Nuclear Information System (INIS)

Yang, Ming-Der; Lin, Min-Der; Lin, Yu-Hao; Tsai, Kang-Ting

2017-01-01

Highlights: • An effective envelope energy performance model (BEM) was developed. • We integrated NSGA-II with the BEM to optimize the green building envelope. • A tradeoff plan of green building design for three conflict objectives was obtained. • The optimal envelope design efficiently reduced the construction cost of green building. - Abstract: To realize the goal of environmental sustainability, improving energy efficiency in buildings is a major priority worldwide. However, the practical design of green building envelopes for energy conservation is a highly complex optimization problem, and architects must make multiobjective decisions. In practice, methods such as multicriteria analyses that entail capitalizing on possibly many (but in nearly any case limited) alternatives are commonly employed. This study investigated the feasibility of applying a multiobjective optimal model on building envelope design (MOPBEM), which involved integrating a building envelope energy performance model with a multiobjective optimizer. The MOPBEM was established to provide a reference for green designs. A nondominated sorting genetic algorithm-II (NSGA-II) was used to achieve a tradeoff design set between three conflicting objectives, namely minimizing the envelope construction cost (ENVCOST), minimizing the envelope energy performance (ENVLOAD), and maximizing the window opening rate (WOPR). A real office building case was designed using the MOPBEM to identify the potential strengths and weaknesses of the proposed MOPBEM. The results showed that a high ENVCOST was expended in simultaneously satisfying the low ENVLOAD and high WOPR. Various designs exhibited obvious cost reductions compared with the original architects' manual design, demonstrating the practicability of the MOPBEM.

Integrated Energy Design of the Building Envelope

DEFF Research Database (Denmark)

Nielsen, Martin Vraa

This thesis describes the outcome of the PhD project Integrated energy design of the building envelope carried out through a combination of scientific dissemination reported through peer-reviewed journals and a wide range of affiliated projects involved in at an architectural firm. The research...

Cost Analysis of Simple Phase Change Material-Enhanced Building Envelopes in Southern U.S. Climates

Energy Technology Data Exchange (ETDEWEB)

Kosny, Jan [Fraunhofer CSE, Cambridge, MA (United States); Shukla, Nitin [Fraunhofer CSE, Cambridge, MA (United States); Fallahi, Ali [Fraunhofer CSE, Cambridge, MA (United States)

2013-01-01

Traditional thermal designs of building envelope assemblies are based on static energy flows, yet building envelopes are subject to varying environmental conditions. This mismatch between the steady-state principles and their dynamic operation can decrease thermal efficiency. Design work supporting the development of low-energy houses showed that conventional insulations may not always be the most cost effective solution to improvement envelope thermal performance. PCM-enhanced building envelopes that simultaneously reduce the total cooling loads and shift the peak-hour loads are the focus of this report.

Towards Energy Demand Reduction in Social Housing Buildings: Envelope System Optimization Strategies

Directory of Open Access Journals (Sweden)

Paula M. Esquivias

2012-07-01

Full Text Available This work evaluates the potential for the reduction of energy demand in residential buildings by acting on the exterior envelope, both in newly constructed buildings and in the retrofitting of existing stock. It focuses on analysing social housing buildings in Mediterranean areas and on quantifying the scope of that reduction in the application of different envelope design strategies, with the purpose of prioritizing their application based on their energy efficiency. The analyses and quantifications were made by means of the generation of energy models with the TRNSYS tool for simple or combined solutions, identifying possible potentials for reduction of the energy demand from 20% to 25%, basically by acting on the windows. The case study was a newly built social housing building of a closed block type located in Seville (Spain. Its constructive techniques and the insulation level of its envelope are standardized for current buildings widespread across Mediterranean Europe.

Towards a fourth skin? sustainability and double-envelope buildings

Energy Technology Data Exchange (ETDEWEB)

Diprose, P.R.; Robertson, G. [Auckland Univ. (New Zealand)

1996-05-01

In several well publicised designs for `green` office buildings, the zone of meditation between inside and outside has been increased by the addition of a second building envelope. When interpreted as exemplars of sustainable architecture, the addition of a second wall in these buildings is questionable both biophysically and psycho-culturally. More constructive design strategies acknowledge the wider biophysical contexts of the human ecosystem, the prudent use of material and energy resources throughout a building`s life, make realistic use of climate, and promote psycho-cultural needs arising out of ecologism. (author)

Simulation-based support for product development of innovative building envelope components

NARCIS (Netherlands)

Loonen, R.C.G.M.; Singaravel, S.; Trcka, M.; Costola, D.; Hensen, J.L.M.

2014-01-01

A need for innovation in building envelope technologies forms a key element of technology roadmaps focusing on improvements in building energy efficiency. Many new products are being proposed and developed, but often, a lack of insights into building integration issues is an obstacle in typical

Development of building envelope structures; Udvikling af klimaskaermskonstruktioner

Energy Technology Data Exchange (ETDEWEB)

Monefeldt Tommerup, H. [Danmarks Tekniske Univ., Lyngby (Denmark); Munch-Andersen, J. [Statens Byggeforskningsinstitut, Hoersholm (Denmark); Kjaer Esbensen, P. [Danmarks Tekniske Univ., Lyngby (Denmark)

2000-08-01

The present report concludes the work concerning the development of building envelope constructions, which can form the basis of new buildings with considerably less heat demand than in the present building regulations. It has been made probable that it is technically possible to build exterior walls with less heat loss than those just complying with the requirements of the current building regulations with no considerable added use of material apart from insulation. In their structure many of the shown constructions resemble types that are used today, while others presuppose that one part of the wall is attached to the other part or possibly to the rafters. Calculations concerning the importance of heat capacity for a 100 m{sup 2} single-family house have been made which confirm that by using heavy rather than light envelope constructions the reduction of the heating requirements is relatively small. Therefore optimisation of the insulation level can be carried out separately on the building components. A method has been developed for the evaluation of the optimum insulation level for the individual building components of the building envelope based on life cycle cost analysis. The method is based on making up the changes in the operational energy costs/ heating-costs and the cost of construction due to a change in the insulation thickness over a 30-year period. The life span of the primary parts of the building envelope is estimated at 100 years. It is assumed that the gross energy consumption that covers the heating requirements and the heat loss (determined by a simple calculation of degree days) changes concurrently with the change in the insulation thickness, which has been proved to be a reasonable approximation. The life cycle cost analysis has been carried out for a test-house of about 100 m{sup 2} and with two different energy price scenarios: 0.60 dkk/kWh (including taxes and VAT) which roughly corresponds to the present energy price level, and 1.20 dkk

TEMPERATURE FIELDS IN THE ZONE OF CONNECTION BETWEEN WINDOW AND BUILDING ENVELOPE

OpenAIRE

V. V. Ivanov; A. N. Butenko; L. V. Karaseva

2011-01-01

Problem statement. To determine additional heat losses through window opening slopes, it is ne-cessary to calculate temperature fields of a wall in the zone of connection between window and building envelope. Two types of building envelopes are considered: solid brick wall and two-layer-wall of bricks and fiber foam concrete block interlayered with air.Results. The results obtained show the influence of a window on the temperature field of wall opening. Different types of wall structures are ...

Tightness of the thermal envelope of office and educational buildings; Klimaskaermens taethed i kontor- og undervisningsbygninger

Energy Technology Data Exchange (ETDEWEB)

Bergsoee, N.C. (SBi, Aalborg (Denmark)); Radisch, N.H.; Nickel, J.; Treldal, J. (Ramboell Danmark A/S, Koebenhavn (Denmark)); Bundesen, E.W.; Nielsen, Carsten (DanEjendomme, Hellerup (Denmark))

2011-07-01

In 2006 tightening of the energy regulations in the Danish Building Regulations were introduced including requirements regarding the tightness of the building envelope. The requirements are, with minor changes, continued in the current Building Regulations, BR10. During the past few years experience has been gained regarding both the actual execution of air tightness measurements and solutions that will lead to more air tight building envelopes. Experiences, however, are primarily related to single family houses. The report presents results of measurements in large buildings and discusses reasons for lack of knowledge and experience on the tightness of the building envelope in large buildings. Apparently, there is a need for dissemination of knowledge on the importance of a tight building envelope both in terms of energy consumption and indoor climate and in terms of the difficulties and costs associated with repairing leaks in a completed envelope. Air tightness must be brought into focus at an early stage in the planning process, and during the construction phase air tightness measurements should be performed, e.g. on facade sections or in parts of the building. The project team has attended a number of measurements in large buildings and further gained access to results of a large number of measurements. In summary, the results show that it is possible to achieve the required tightness, and in most buildings the results are better than the requirement of a maximum of 1.5 l/s per m{sub 2}. (Author)

CISBAT 2007 - Design and renovation of building envelopes (bioclimatic architecture)

Energy Technology Data Exchange (ETDEWEB)

NONE

2007-07-01

This is the second part of the proceedings of the 2007 CISBAT conference on Renewables in a changing climate, held in Lausanne, Switzerland. On the subject of sustainable building envelopes the following oral contributions are summarised: 'Flexible photovoltaics integrated in transparent membrane and pneumatic foil constructions', 'Development of a numerical thermal model for double skin facades', 'Thermal performance analysis for an electrochromic vacuum glazing with low emittance coatings', 'Challenging the public building sector: optimization of energy performance by sustainable strategies', 'Simulation of the thermal performance of a climate adaptive skin', 'Possibilities for upgrading prefabricated concrete building envelopes', 'Experimental study of airflow and heat transfer in a double skin facade with blinds', 'Energy efficiency of a glazing system - Case study: a dynamic glazing and double skin facades - the use of venetian blinds and night ventilation for saving energy on mediterranean climate'. Poster-sessions on the subject include 'Adaptive building envelopes design ', 'GRC facade panels in Brazil', 'Solar absorptance of building opaque surfaces', 'Evaluating the thermal behavior of exterior walls (in residential buildings of hot-dry climate of Yazd)', 'Energy performance of buildings and local energy policy: the case of new residential buildings in Greve in Chianti (Firenze)', 'Space heating and domestic hot water energy demand in high-level-insulation multi-storey buildings in Tuscany (Italy)', 'Is 2000 W society possible, affordable, and socially acceptable for the Vaud existing school building?', 'Development of simplified method for measuring solar shading performance of windows', 'Studies of ecological architecture in China's Loess Plateau region', 'Contemporary mud

Residential building envelope heat gain and cooling energy requirements

International Nuclear Information System (INIS)

Lam, Joseph C.; Tsang, C.L.; Li, Danny H.W.; Cheung, S.O.

2005-01-01

We present the energy use situation in Hong Kong from 1979 to 2001. The primary energy requirement (PER) nearly tripled during the 23-year period, rising from 195,405 TJ to 572,684 TJ. Most of the PER was used for electricity generation, and the electricity use in residential buildings rose from 7556 TJ (2099 GWh) to 32,799 TJ (9111 GWh), an increase of 334%. Air-conditioning accounted for about 40% of the total residential sector electricity consumption. A total of 144 buildings completed in the month of June during 1992-2001 were surveyed. Energy performance of the building envelopes was investigated in terms of the overall thermal transfer value (OTTV). To develop the appropriated parameters used in OTTV calculation, long-term measured weather data such as ambient temperature (1960-2001), horizontal global solar radiation (1992-2001) and global solar radiation on vertical surfaces (1996-2001) were examined. The OTTV found varied from 27 to 44 W/m 2 with a mean value of 37.7 W/m 2 . Building energy simulation technique using DOE-2.1E was employed to determine the cooling requirements and hence electricity use for building envelope designs with different OTTVs. It was found that cooling loads and electricity use could be expressed in terms of a simple two-parameter linear regression equation involving OTTV

Switching from static to adaptable and dynamic building envelopes: A paradigm shift for the energy efficiency in buildings

Directory of Open Access Journals (Sweden)

Marco Perino

2015-11-01

Full Text Available The key role of the building envelope in attaining building energy efficiency and satisfactory indoor comfort has long been established. Nevertheless, until recent times, all efforts and attention have mainly been focused on increasing and optimizing the thermal insulation of the envelope components. This strategy was a winning approach for a long time, but its limitations became obvious when users and designers started to consider the overall energy demand of a building and started to aim for Zero Energy Building (ZEB or nearly ZEB goals. New and more revolutionary concepts and technologies needed to be developed to satisfy such challenging requirements. The potential benefits of this technological development are relevant since the building envelope plays a key role in controlling the energy and mass flows from outdoors to indoors (and vice versa and, moreover, the facades offer a significant opportunity for solar energy exploitation. Several researches have demonstrated that the limitation of the existing facades could be overcome only by switching from ‘static’ to ‘responsive’ and ‘dynamic’ systems, such as Multifunctional Facade Modules (MFMs and Responsive Building Elements (RBE. These components are able to continuously and pro-actively react to outdoor and indoor environment conditions and facilitate and enhance the exploitation of renewable and low exergy sources. In order to reduce the energy demand, to maximize the indoor comfort conditions and to produce energy at the site, these almost ‘self-sufficient’, or even ‘positive energy’ building skins frequently incorporate different technologies and are functionally connected to other building services and installations. An overview of the technological evolution of the building envelope that has taken place, ranging from traditional components to the innovative skins, will be given in this paper, while focusing on the different approaches that have characterized this

Experimental building with new types of building envelope structures. Part 1: Structures/systems. Building system: Brick walls; Forsoegshus med nye typer klimaskaermskonstruktioner. Del 1: Konstruktioner/systemer - Byggesystem: Fuldmuret

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-07-01

The house described in this report is one of several experimental houses forming part of the project 'Experimental buildings with new types of building envelope structures'. One purpose of the project is to demonstrate that it is possible to build typical single-family houses with an energy consumption that meets expected increased building regulations. Furthermore, it is important that the houses can be made securely as regards construction technology and within reasonable financial limits. Thus, the purpose is also to contribute to strengthen the development of improved building envelope structures. Another purpose is to carry out detailed measurements of energy consumption in order to validate thermal performance of future building envelope structures. The report describes the constructive design and energy systems of the house plus heat loss calculations and expected energy consumption. (BA)

Advancing the manufacture of complex geometry GFRC for today's building envelopes

NARCIS (Netherlands)

Henriksen, T.N.

2017-01-01

Thin-walled glass fibre reinforced concrete (GFRC) panels are being used as the primary cladding material on many landmark buildings especially in the last decade. GFRC is an ideal material for building envelopes because it is durable, it can resist fire and the environmental impact is low compared

Analysis for Building Envelopes and Mechanical Systems Using 2012 CBECS Data

Energy Technology Data Exchange (ETDEWEB)

Winiarski, David W.; Halverson, Mark A.; Butzbaugh, Joshua B.; Cooke, Alan L.; Bandyopadhyay, Gopal K.; Elliott, Douglas B.

2018-03-14

This report describes the aggregation and mapping of certain building characteristics data available in the most recent Commercial Building Energy Consumption Survey (CBECS) (DOE EIA 2012) to describe most typical building construction practices. This report provides summary data for potential use in the support of modifications to the Pacific Northwest National Laboratory’s commercial building prototypes used for building energy code analysis. Specifically, this report outlines findings and most typical design choices for certain building envelope and heating, ventilating, and air-conditioning (HVAC) system choices.

Moisture condensation on building envelopes in differential ventilated spaces in the tropics: quantitative assessment of influencing factors

Directory of Open Access Journals (Sweden)

Ali Maisarah

2016-01-01

Full Text Available Ventilation systems play a significant role in maintaining the indoor thermal and hygric balance. Nevertheless, the systems had been implicated to result in many problems. In the tropical climate, especially for energy efficiency purposes, building spaces are operated with differential ventilation. Such spaces operate on 24-hrs basis, some on 8-hrs while others are either naturally ventilated or served with mechanical supply-exhaust fan systems with non-conditioned outdoor air. This practice had been found to result in condensation problems. This study involves a quantitative appraisal of the effect of operative conditions and hygrothermal quality of building envelopes on condensation risk. The in-situ experiment is combined with an analytical approach to assessing the hygrothermal quality of building envelopes in a tropical climate building under differential ventilation between adjacent spaces. The case-studied building is with a known history of condensation and associated damages including mould growth. The microclimate measurement and hygrothermal performance of the wall and floor against condensation and mould growth risks had been previously reported elsewhere. As a step further, the present study evaluates the effects of various envelope insulation types and configurations together with the HVAC cooling set-points on envelope hygrothermal performance. The results revealed that overcooling the air-conditioned side increases condensation risk on the non-air-conditioned side of the envelopes. The envelopes failed criteria for surface condensation at existing operative conditions irrespective of envelope hygrothermal quality improvements. However, the envelope performed well at improved cooling operative conditions even at existing envelope hygrothermal quality. It is, therefore, important to ascertain the envelope hygrothermal quality as well the cooling operative conditions while embarking on energy efficiency operations in mechanical

Utilizing the building envelope for power generation and conservation

International Nuclear Information System (INIS)

Lee, M.C.; Kuo, C.H.; Wang, F.J.

2016-01-01

Heat loading of the building envelope is caused by strong solar radiation and incorrect material selection. As a result of the heat loading of the building envelope, the indoor air temperature is increased, resulting in high energy consumption by air conditioners to maintain a comfortable indoor thermal environment. This study explores the use of a hybrid wall integrated with heat collectors (water piping system) and solar thermal power generators, which absorbs solar radiation through water to reduce heat transmission thereby saving energy and generating power. Power generation is achieved by an OD (oscillator device) that installed between a water tank (hot side) and building interior (cold side). The device acts by temperature differences between hot air (expansion) and cold air (contraction). CFD (computational dynamic simulation) was used to assess the effects of the hybrid wall on the interior environment. The results show that exterior heat is absorbed by cool water thereby reducing the heat transmission into the building, resulting in less energy consumption by air conditioners and power generation by use of temperature differences. - Highlights: • This study explores a hybrid building wall to save energy and generate power. • Power generators operated by air pressure change via hot tank and cool interior. • Less energy consumption by air conditioners and heating water. • Performance of CFD simulated results and experiment results are similar. • The energy saving efficiency is around 15 kWh/day via hybrid wall in west façade.

Owners perception on the adoption of building envelope energy efficiency measures in Swedish detached houses

Energy Technology Data Exchange (ETDEWEB)

Nair, Gireesh [Ecotechnology, Mid Sweden University, SE-83125 Ostersund (Sweden); Gustavsson, Leif [Ecotechnology, Mid Sweden University, SE-83125 Ostersund (Sweden); Mahapatra, Krushna [Ecotechnology, Mid Sweden University, SE-83125 Ostersund (Sweden)

2010-07-15

The paper focuses on Swedish homeowners' need for and perceptions about adopting building envelop energy efficiency measures. The paper is based on a questionnaire survey of 3059 homeowners (response rate of 36%) selected by stratified random sampling during the summer of 2008. The results showed that 70-90% of the respondents had no intention of adopting such a measure over the next 10 years. The main reasons for non-adoption were that homeowners were satisfied with the physical condition, thermal performance, and aesthetics of their existing building envelope components. A greater proportion of respondents perceived that improved attic insulation has more advantages than energy efficient windows and improved wall insulation, but windows were more likely to be installed than improved attic insulation. Respondents gave high priority to economic factors in deciding on an energy efficiency measure. Interpersonal sources, construction companies, installers, and energy advisers were important sources of information for homeowners as they planned to adopt building envelope energy efficiency measures. Policy measures to facilitate the rate of adoption of energy efficient building envelope measures are discussed.

Owners perception on the adoption of building envelope energy efficiency measures in Swedish detached houses

International Nuclear Information System (INIS)

Nair, Gireesh; Gustavsson, Leif; Mahapatra, Krushna

2010-01-01

The paper focuses on Swedish homeowners' need for and perceptions about adopting building envelop energy efficiency measures. The paper is based on a questionnaire survey of 3059 homeowners (response rate of 36%) selected by stratified random sampling during the summer of 2008. The results showed that 70-90% of the respondents had no intention of adopting such a measure over the next 10 years. The main reasons for non-adoption were that homeowners were satisfied with the physical condition, thermal performance, and aesthetics of their existing building envelope components. A greater proportion of respondents perceived that improved attic insulation has more advantages than energy efficient windows and improved wall insulation, but windows were more likely to be installed than improved attic insulation. Respondents gave high priority to economic factors in deciding on an energy efficiency measure. Interpersonal sources, construction companies, installers, and energy advisers were important sources of information for homeowners as they planned to adopt building envelope energy efficiency measures. Policy measures to facilitate the rate of adoption of energy efficient building envelope measures are discussed.

Owners perception on the adoption of building envelope energy efficiency measures in Swedish detached houses

Energy Technology Data Exchange (ETDEWEB)

Nair, Gireesh; Gustavsson, Leif; Mahapatra, Krushna [Ecotechnology, Mid Sweden University, SE-83125 Oestersund (Sweden)

2010-07-15

The paper focuses on Swedish homeowners' need for and perceptions about adopting building envelop energy efficiency measures. The paper is based on a questionnaire survey of 3059 homeowners (response rate of 36%) selected by stratified random sampling during the summer of 2008. The results showed that 70-90% of the respondents had no intention of adopting such a measure over the next 10 years. The main reasons for non-adoption were that homeowners were satisfied with the physical condition, thermal performance, and aesthetics of their existing building envelope components. A greater proportion of respondents perceived that improved attic insulation has more advantages than energy efficient windows and improved wall insulation, but windows were more likely to be installed than improved attic insulation. Respondents gave high priority to economic factors in deciding on an energy efficiency measure. Interpersonal sources, construction companies, installers, and energy advisers were important sources of information for homeowners as they planned to adopt building envelope energy efficiency measures. Policy measures to facilitate the rate of adoption of energy efficient building envelope measures are discussed. (author)

Windows and Building Envelope Research and Development: A Roadmap for Emerging Technologies

Energy Technology Data Exchange (ETDEWEB)

none,

2014-02-01

This Building Technologies Office (BTO) Research and Development (R&D) Roadmap identifies priority windows and building envelope R&D areas of interest. Cost and performance targets are identified for each key R&D area. The roadmap describes the technical and market challenges to be overcome, R&D activities and milestones, key stakeholders, and potential energy savings that could result if cost and performance targets are met. Methods for improving technology performance and specific strategies for reducing installed costs and mitigating any other market barriers, which would increase the likelihood of mass-market technology adoption, are identified. This roadmap is a useful resource for public and private decision makers evaluating and pursuing high-impact R&D focused on advancing next-generation energy efficient windows and building envelope technologies.

The potential of building envelope greening to achieve quietness

NARCIS (Netherlands)

Van Renterghem, T.; Hornikx, M.C.J.; Forssén, J.; Botteldooren, D.

2013-01-01

Reduction of noise is one of the multiple benefits of building envelope greening measures. The potential of wall vegetation systems, green roofs, vegetated low screens at roof edges, and also combinations of such treatments, have been studied by means of combining 2D and 3D full-wave numerical

Building envelope influence on the annual energy performance in office buildings

Directory of Open Access Journals (Sweden)

Harmati Norbert L.

2016-01-01

Full Text Available The objective of the research is to determine the quantitative influence of building envelope on the annual heating and cooling energy demand in office buildings demonstrated on a reference office-tower building located in Novi Sad, Serbia. The investigation intended to find preferable and applicable solutions for energy performance improvement in currently inefficient office buildings. A comparative and evaluative analysis was performed among the heating energy expenses and simulated values from the multi-zone model designed in EnergyPlus engine. The research determines an improved window to wall ratio using dynamic daylight simulation and presents the influence of glazing parameters (U-value, Solar heat gain coefficient - SHGC on the annual energy performance. Findings presented window to wall ratio reduction down to 30% and point out the significance of the SHGC parameter on the overall energy performance of buildings with high internal loads. The calculation of the air-ventilation energy demand according to EN 15251 is included respectively. Results offer effective methods for energy performance improvement in temperate climate conditions.

Phase Change Materials in Transparent Building Envelopes: A Strengths, Weakness, Opportunities and Threats (SWOT Analysis

Directory of Open Access Journals (Sweden)

Ilaria Vigna

2018-01-01

Full Text Available Building envelopes can play a crucial role in building improvement efficiency, and the adoption of Phase Change Materials (PCMs, coupled with transparent elements, may: (i allow a better control of the heat flows from/to the outdoor environment, (ii increase the exploitation of solar energy at a building scale and (iii modulate light transmission in order to prevent glare effects. Starting from a literature review, focused on experimental works, this research identifies the main possible integrations of PCMs in transparent/translucent building envelope components (in glazing, in shutters and in multilayer façade system in order to draw a global picture of the potential and limitations of these technologies. Transparent envelopes with PCMs have been classified from the simplest “zero” technology, which integrates the PCM in a double glass unit (DGU, to more complex solutions—with a different number of glass cavities (triple glazed unit TGU, different positions of the PCM layer (internal/external shutter, and in combination with other materials (TIM, aerogel, prismatic solar reflector, PCM curtain controlled by an electric pump. The results of the analysis have been summarised in a Strengths, Weakness, Opportunities and Threats (SWOT analysis table to underline the strengths and weaknesses of transparent building envelope components with PCMs, and to indicate opportunities and threats for future research and building applications.

Building envelope for New Buildings and Energy Renovation of Existing Buildings. Project results

DEFF Research Database (Denmark)

Rudbeck, Claus Christian; Rose, Jørgen; Esbensen, Peter Kjær

1999-01-01

of heat- and moistureflow is insufficiently documented for large insulation thicknesses. Thermal bridges, for instance, plays a larger role for the overall heat loss in these constructions, and moisture in insulation materials will decrease the overall performance of the construction.Due to these facts...... on the following subjects:Scientific basis for calculation programs, Development of calculationsmethods for heat transfer, Development of new building envelope components, Roofing system based on wooden roof elements, Roofing system with drying properties, Moisture uptake and drying from brick constructions...

Hygrothermal Simulation: A Tool for Building Envelope Design Analysis

Science.gov (United States)

Samuel V. Glass; Anton TenWolde; Samuel L. Zelinka

2013-01-01

Is it possible to gauge the risk of moisture problems while designing the building envelope? This article provides a brief introduction to computer-based hygrothermal (heat and moisture) simulation, shows how simulation can be useful as a design tool, and points out a number of im-portant considerations regarding model inputs and limita-tions. Hygrothermal simulation...

Shape Control of Responsive Building Envelopes

DEFF Research Database (Denmark)

Foged, Isak Worre; Kirkegaard, Poul Henning; Christensen, Jesper Thøger

2010-01-01

The present paper considers shape control of adaptive architectural structures for improvement of structural performance by recognizing changes in their environments and loads, adapting to meet goals, and using past events to improve future performance or maintain serviceability. The general scop...... environmental system to a primary structural system joint into a collective behavioral system equipment with an actuator system is presented....... alternatives. The adaptive structure is a proposal for a responsive building envelope which is an idea of a first level operational framework for present and future investigations towards performance based responsive architectures through a set of responsive typologies. A mock-up concept of a secondary...

Numerical simulation of phase change material composite wallboard in a multi-layered building envelope

International Nuclear Information System (INIS)

Zwanzig, Stephen D.; Lian, Yongsheng; Brehob, Ellen G.

2013-01-01

Highlights: ► A numerical method to study the heat transfer through a PCM composite wallboard is presented. ► PCM wallboard can reduce energy consumption and shift peak electricity load. ► There is an optimal location for the PCM wallboard in the building envelop. ► The PCM wallboard performance depends on weather conditions. - Abstract: Phase change materials (PCMs) have the capability to store/release massive latent heat when undergoing phase change. When impregnated or encapsulated into wallboard or concrete systems, PCMs can greatly enhance their thermal energy storage capacity and effective thermal mass. When used in the building envelope PCM wallboard has the potential to improve building operation by reducing the energy requirement for maintaining thermal comfort, downsizing the AC/heating equipment, and shifting the peak load from the electrical grid. In this work we numerically studied the potential of PCM on energy saving for residential homes. For that purpose we solved the one-dimensional, transient heat equation through the multi-layered building envelope using the Crank–Nicolson discretization scheme. A source term is incorporated to account for the thermal-physical properties of the composite PCM wallboard. Using this code we examined a PCM composite wallboard incorporated into the walls and roof of a typical residential building across various climate zones. The PCM performance was studied under all seasonal conditions using the latest typical meteorological year (TMY3) data for exterior boundary conditions. Our simulations show that PCM performance highly depends on the weather conditions, emphasizing the necessity to choose different PCMs at different climate zones. Comparisons were also made between different PCM wallboard locations. Our work shows that there exists an optimal location for PCM placement within building envelope dependent upon the resistance values between the PCM layer and the exterior boundary conditions. We further

Study of potential nonconformities of a new recreation center building's envelope

Science.gov (United States)

Stanescu, M.; Kajl, S.; Lamarche, L.

2016-09-01

This article presents a building envelope's analysis in order to verify the compliance with mandatory provisions of the Model National Energy Code for Buildings in Canada (MNECB 1997). Because some of the requirements are «not met», investigations were carried out to provide justifications in order to prove that the building can be considered as an exception to the mandatory provisions of MNECB. Therefore, we evaluate the impact of three (3) potential nonconformities of the building's walls on the building energy performance. In regards to article 3.1.1.1.4 of MNECB, there is an exception if it can be proved that permanent process (like heat recovery of refrigeration compressors) can produce at all times enough heat that no other heating source is required. First of all, by using simulation, we were able to indicate that almost all building's heating will be provided by energy recovery from ice rinks refrigeration systems (99.2%). Secondly, by using an energy analysis carried out with HEAT2 software, we can show that the increase of heating energy demand caused by the 3 studied walls is very low. This represents an increase of the heating energy demand of only 0.2%, and this, regardless of the heat recovery process. Because the nonconforming wall sections are small (0.97% of the envelope area), this mainly explains the minor impact in terms of building performance. In conclusion, according to the results obtained, we were able to recommend the building for consideration as an exception to the mandatory provisions of MNECB.

Genetic algorithm for building envelope calibration

International Nuclear Information System (INIS)

Ramos Ruiz, Germán; Fernández Bandera, Carlos; Gómez-Acebo Temes, Tomás; Sánchez-Ostiz Gutierrez, Ana

2016-01-01

Highlights: • Calibration methodology using Multi-Objective Genetic Algorithm (NSGA-II). • Uncertainty analysis formulas implemented directly in EnergyPlus. • The methodology captures the heat dynamic of the building with a high level of accuracy. • Reduction in the number of parameters involved due to sensitivity analysis. • Cost-effective methodology using temperature sensors only. - Abstract: Buildings today represent 40% of world primary energy consumption and 24% of greenhouse gas emissions. In our society there is growing interest in knowing precisely when and how energy consumption occurs. This means that consumption measurement and verification plans are well-advanced. International agencies such as Efficiency Valuation Organization (EVO) and International Performance Measurement and Verification Protocol (IPMVP) have developed methodologies to quantify savings. This paper presents a methodology to accurately perform automated envelope calibration under option D (calibrated simulation) of IPMVP – vol. 1. This is frequently ignored because of its complexity, despite being more flexible and accurate in assessing the energy performance of a building. A detailed baseline energy model is used, and by means of a metaheuristic technique achieves a highly reliable and accurate Building Energy Simulation (BES) model suitable for detailed analysis of saving strategies. In order to find this BES model a Genetic Algorithm (NSGA-II) is used, together with a highly efficient engine to stimulate the objective, thus permitting rapid achievement of the goal. The result is a BES model that broadly captures the heat dynamic behaviour of the building. The model amply fulfils the parameters demanded by ASHRAE and EVO under option D.

Evolution of building envelope construction techniques in coastal British Columbia

Energy Technology Data Exchange (ETDEWEB)

Mattock, C.; Ito, K.; Oshikawa, T. [International Eco-House Inc., (Canada)

1999-11-01

Changes in the significant evolutionary development over the past 3 years in building envelope construction for multi storey wood frame housing in British Columbia are described. The urban areas of this region are characterized by a maritime climate which features a high frequency of wind driven rain and little accumulation of snow. Buildings are exposed to high wetting with little drying potential, and moderate temperatures allow for fungal growth even in the winter. While as in the rest of Canada wetting is often due to condensation of moisture contained in indoor air as it leaks out of the building, in British Columbia wind driven rain is a much larger source of moisture. Given this, the following principles of moisture control have been promoted to the B.C. building industry in order of priority: 1) deflection - using parts and elements of the building such as overhangs and flashings that reduce the exposure of the exterior walls to rain, 2) drainage - using envelope assemblies that will then redirect liquid water to the outside, 3) employing drying elements that promote drying through diffusion such as highly permeable wall sheathings, and 4) use of durable materials - using materials that resist rot such as treated lumber, stainless steel fastenings, etc. A variety of air barrier systems other than the conventional sealed polyethylene approach have been employed because of the introduction of recent building code requirements for enhanced airtightness and air barrier durability combined with the use of rain screen construction. This variety of air barrier systems includes: an airtight drywall, an exterior permeable membrane, and an exterior impermeable membrane.

Biomimetic Envelopes

OpenAIRE

Ilaria Mazzoleni

2010-01-01

How to translate the lessons learned from the analysis and observation of the animal world is the design learning experience presented in this article. Skin is a complex and incredibly sophisticated organ that performs various functions, including protection, sensation and heat and water regulation. In a similar way building envelopes serve multiple roles, as they are the interface between the building inhabitants and environmental elements. The resulting architectural building envelopes prot...

Building envelope regulations on thermal comfort in glass facade buildings and energy-saving potential for PMV-based comfort control

Energy Technology Data Exchange (ETDEWEB)

Hwang, Ruey-Lung; Shu, Shiu-Ya [Department of Architecture, National United University, 1, Lien-Da, Kung-Ching Li, Miaoli, 36003 (China)

2011-04-15

This paper presents an investigation of the effect of building envelope regulation on thermal comfort and on the energy-saving potential for PMV-based comfort control in glass facade buildings. Occurrences and severity of overheating, based on the PMV-PPD model contained in ISO 7730, were used for the thermal comfort assessment. Parametric study simulations for an actual building with a large glass facade were carried out to predict the changes in thermal comfort levels in a space due to different glazing types, depths of overhang and glazing areas, which are the key parameters of the building envelope regulation index, named ENVLOAD, in Taiwan. The result demonstrates that the ENVLOAD has significant effect on thermal comfort. Additionally, comparative simulations between PMV-based comfort control and conventional thermostatic control were performed to investigate the changes in the energy-saving potential of a thermal comfort-controlled space due to changes of its ENVLOAD. The results demonstrate that the energy-saving potential in a PMV-based controlled space increases with low ENVLOAD conditions. (author)

Dynamic window daylighting systems: electropolymeric technology for solar responsive building envelopes

Science.gov (United States)

Krietemeyer, Elizabeth A.; Smith, Shane I.; Dyson, Anna H.

2011-04-01

Human health and energy problems associated with the lack of control of sunlight in contemporary buildings have necessitated research into dynamic windows for energy efficient buildings. Existing window technologies have made moderate progress towards greater energy performance for facades but remain limited in their response to dynamic solar conditions, building energy requirements, and variable user preferences for visual comfort. Recent developments in electropolymeric display technology provide opportunities to transfer electroactive polymers to windows that can achieve high levels of geometric and spectral selectivity through the building envelope in order to meet the lighting, thermal and user requirements of occupied spaces. Experimental simulations that investigate daylight quality, energy performance, and architectural effects of electropolymeric glazing technology are presented.

Low-Cost Bio-Based Phase Change Materials as an Energy Storage Medium in Building Envelopes

Energy Technology Data Exchange (ETDEWEB)

Biswas, Kaushik [ORNL; Abhari, Mr. Ramin [Renewable Energy Group, Inc.; Shukla, Dr. Nitin [Fraunhofer USA, Center for Sustainable Energy Systems (CSE), Boston; Kosny, Dr. Jan [Fraunhofer USA, Center for Sustainable Energy Systems (CSE), Boston

2015-01-01

A promising approach to increasing the energy efficiency of buildings is the implementation of phase change material (PCM) in building envelope systems. Several studies have reported the energy saving potential of PCM in building envelopes. However, wide application of PCMs in building applications has been inhibited, in part, by their high cost. This article describes a novel paraffin product made of naturally occurring fatty acids/glycerides trapped into high density polyethylene (HDPE) pellets and its performance in a building envelope application, with the ultimate goal of commercializing a low-cost PCM platform. The low-cost PCM pellets were mixed with cellulose insulation, installed in external walls and field-tested under natural weatherization conditions for a period of several months. In addition, several PCM samples and PCM-cellulose samples were prepared under controlled conditions for laboratory-scale testing. The laboratory tests were performed to determine the phase change properties of PCM-enhanced cellulose insulation both at microscopic and macroscopic levels. This article presents the data and analysis from the exterior test wall and the laboratory-scale test data. PCM behavior is influenced by the weather and interior conditions, PCM phase change temperature and PCM distribution within the wall cavity, among other factors. Under optimal conditions, the field data showed up to 20% reduction in weekly heat transfer through an external wall due to the PCM compared to cellulose-only insulation.

Low-Cost Phase Change Material for Building Envelopes

Energy Technology Data Exchange (ETDEWEB)

Abhari, Ramin [Renewable Energy Group

2015-08-06

A low-cost PCM process consisting of conversion of fats and oils to PCM-range paraffins, and subsequent “encapsulation” of the paraffin using conventional plastic compounding/pelletizing equipment was demonstrated. The PCM pellets produced were field-tested in a building envelope application. This involved combining the PCM pellets with cellulose insulation, whereby 33% reduction in peak heat flux and 12% reduction in heat gain was observed (average summertime performance). The selling price of the PCM pellets produced according to this low-cost process is expected to be in the $1.50-$3.00/lb range, compared to current encapsulated PCM price of about $7.00/lb. Whole-building simulations using corresponding PCM thermal analysis data suggest a payback time of 8 to 16 years (at current energy prices) for an attic insulation retrofit project in the Phoenix climate area.

Dynamic Exergy Analysis for the Thermal Storage Optimization of the Building Envelope

Directory of Open Access Journals (Sweden)

Valentina Bonetti

2017-01-01

Full Text Available As a measure of energy “quality”, exergy is meaningful for comparing the potential for thermal storage. Systems containing the same amount of energy could have considerably different capabilities in matching a demand profile, and exergy measures this difference. Exergy stored in the envelope of buildings is central in sustainability because the environment could be an unlimited source of energy if its interaction with the envelope is optimised for maintaining the indoor conditions within comfort ranges. Since the occurring phenomena are highly fluctuating, a dynamic exergy analysis is required; however, dynamic exergy modelling is complex and has not hitherto been implemented in building simulation tools. Simplified energy and exergy assessments are presented for a case study in which thermal storage determines the performance of seven different wall types for utilising nocturnal ventilation as a passive cooling strategy. Hourly temperatures within the walls are obtained with the ESP-r software in free-floating operation and are used to assess the envelope exergy storage capacity. The results for the most suitable wall types were different between the exergy analysis and the more traditional energy performance indicators. The exergy method is an effective technique for selecting the construction type that results in the most favourable free-floating conditions through the analysed passive strategy.

Low-cost phase change material as an energy storage medium in building envelopes: Experimental and numerical analyses

International Nuclear Information System (INIS)

Biswas, Kaushik; Abhari, Ramin

2014-01-01

Highlights: • Testing of a low-cost bio-PCM in an exterior wall under varying weather conditions. • Numerical model validation and annual simulations of PCM-enhanced cellulose insulation. • Reduced wall-generated cooling electricity consumption due to the application of PCM. • PCM performance was sensitive to its location and distribution within the wall. - Abstract: A promising approach to increasing the energy efficiency of buildings is the implementation of a phase change material (PCM) in the building envelope. Numerous studies over the last two decades have reported the energy saving potential of PCMs in building envelopes, but their wide application has been inhibited, in part, by their high cost. This article describes a novel PCM made of naturally occurring fatty acids/glycerides trapped into high density polyethylene (HDPE) pellets and its performance in a building envelope application. The PCM–HDPE pellets were mixed with cellulose insulation and then added to an exterior wall of a test building in a hot and humid climate, and tested over a period of several months. To demonstrate the efficacy of the PCM-enhanced cellulose insulation in reducing the building envelope heat gains and losses, a side-by-side comparison was performed with another wall section filled with cellulose-only insulation. Further, numerical modeling of the test wall was performed to determine the actual impact of the PCM–HDPE pellets on wall-generated heating and cooling loads and the associated electricity consumption. The model was first validated using experimental data and then used for annual simulations using typical meteorological year (TMY3) weather data. This article presents the experimental data and numerical analyses showing the energy-saving potential of the new PCM

To Investigate the Influence of Building Envelope and Natural Ventilation on Thermal Heat Balance in Office Buildings in Warm and Humid Climate

Science.gov (United States)

Kini, Pradeep G.; Garg, Naresh Kumar; Kamath, Kiran

2017-07-01

India’s commercial building sector is witnessing robust growth. India continues to be a key growth market among global corporates and this is reflective in the steady growth in demand for prime office space. A recent trend that has been noted is the increase in demand for office spaces not just in major cities but also in smaller tier II and Tier III cities. Growth in the commercial building sector projects a rising trend of energy intensive mechanical systems in office buildings in India. The air conditioning market in India is growing at 25% annually. This is due to the ever increasing demand to maintain thermal comfort in tropical regions. Air conditioning is one of the most energy intensive technologies which are used in buildings. As a result India is witnessing significant spike in energy demand and further widening the demand supply gap. Challenge in India is to identify passive measures in building envelope design in office buildings to reduce the cooling loads and conserve energy. This paper investigates the overall heat gain through building envelope components and natural ventilation in warm and humid climate region through experimental and simulation methods towards improved thermal environmental performance.

Parameter design for a phase change material board installed on the inner surface of building exterior envelopes for cooling in China

International Nuclear Information System (INIS)

Sun, Xiaoqin; Zhang, Quan; Medina, Mario A.; Lee, Kyoung Ok; Liao, Shuguang

2016-01-01

Highlights: • Phase change material (PCM) boards were simulated in building envelopes. • The buildings were located in four cities with different climatic conditions. • Energy and mass efficiency was proposed to evaluate utilization of PCM board. • The optimal melting temperature increased with increasing mean air temperature. - Abstract: Phase change materials (PCMs) can be used for building envelope thermal management and for energy conservation because of their potential to absorb and release large amounts of heat with small wall temperature variations. In this paper, the heat transfer theory of a PCM board used for building envelopes is presented, together with a mathematical model based on the moving heat-source method. It was found that the model accurately predicted the position of the solid–liquid interface in time and space, comparing with the published data. Energy and mass efficiency (EME) was proposed to evaluate the energy efficiency of PCM boards in office buildings located in various climatic regions in China for cooling. The influences on EME of parameters, including melting temperature of PCM, PCM board thickness and the heat transfer coefficient of building envelope, were analyzed. The optimal melting temperatures of PCM board, which resulted in the peak EME, in office building were 24.1 °C in Shenyang, 25.0 °C in Kunming, 25.3 °C in Zhengzhou and 25.5 °C Changsha, respectively. The EME increased with the increasing heat transfer coefficient of building envelope. For the city of Changsha with higher outdoor air temperature, none of the PCM boards modeled contributed effectively.

Study of an experimental methodology for thermal properties diagnostic of building envelop

Science.gov (United States)

Yang, Yingying; Sempy, Alain; Vogt Wu, Tingting; Sommier, Alain; Dumoulin, Jean; Batsale, Jean Christophe

2017-04-01

The building envelope plays a critical role in determining levels of comfort and building efficiency. Its real thermal properties characterization is of major interest to be able to diagnose energy efficiency performance of buildings (new construction and retrofitted existing old building). Research and development on a possible methodology for energy diagnostic of the building envelop is a hot topic and necessary trend. Many kinds of sensors and instruments are used for the studies. The application of infrared (IR) thermography in non-destructive evaluation has been widely employed for qualitative evaluations for building diagnostics; meanwhile, the IR thermography technology also has a large potentiality for the evaluation of the thermal characteristics of the building envelope. Some promising recent research studies have been carried out with such contactless measurement technique. Nevertheless, research efforts are still required for in situ measurements under natural environmental conditions. In order to develop new solutions for non-intrusive evaluation of local thermal performance, enabling quantitative assessment of thermal properties of buildings and materials, experiments were carried out on a multi-layer pratical scale wall fixed on a caisson placed in a climatic chamber. Six halogen lamps (1.5 kW for each lamp) placed in front of objective wall were used to emulate sunny conditions. The radiative heat flux emitted was monitored and modulated with time according to typical weather data set encountered in France. Both steady state and transient regime heat transfer were studied during these experiments. Contact sensors (thermocouples, heat flux meters, Peltier sensors) and non-contact sensors (thermal IR camera, pyranometer) were used to measure the temperatures and heat flux density evolution. It has to be noticed that the Peltier sensors have been tuned and used with a specific processing to set them compliant for heat flux density measurements. The

Multiobjective optimisation of energy systems and building envelope retrofit in a residential community

International Nuclear Information System (INIS)

Wu, Raphael; Mavromatidis, Georgios; Orehounig, Kristina; Carmeliet, Jan

2017-01-01

Highlights: • Simultaneous optimisation of building envelope retrofit and energy systems. • Retrofit and energy systems change interact and should be considered simultaneously. • Case study quantifies cost-GHG emission tradeoffs for different retrofit options. - Abstract: In this paper, a method for a multi-objective and simultaneous optimisation of building energy systems and retrofit is presented. Tailored to be suitable for the diverse range of existing buildings in terms of age, size, and use, it combines dynamic energy demand simulation to explore individual retrofit scenarios with an energy hub optimisation. Implemented as an epsilon-constrained mixed integer linear program (MILP), the optimisation matches envelope retrofit with renewable and high efficiency energy supply technologies such as biomass boilers, heat pumps, photovoltaic and solar thermal panels to minimise life cycle cost and greenhouse gas (GHG) emissions. Due to its multi-objective, integrated assessment of building transformation options and its ability to capture both individual building characteristics and trends within a neighbourhood, this method is aimed to provide developers, neighbourhood and town policy makers with the necessary information to make adequate decisions. Our method is deployed in a case study of typical residential buildings in the Swiss village of Zernez, simulating energy demands in EnergyPlus and solving the optimisation problem with CPLEX. Although common trade-offs in energy system and retrofit choice can be observed, optimisation results suggest that the diversity in building age and size leads to optimal strategies for retrofitting and building system solutions, which are specific to different categories. With this method, GHG emissions of the entire community can be reduced by up to 76% at a cost increase of 3% compared to the current emission levels, if an optimised solution is selected for each building category.

Can envelope codes reduce electricity and CO2 emissions in different types of buildings in the hot climate of Bahrain?

International Nuclear Information System (INIS)

Radhi, H.

2009-01-01

The depletion of non-renewable resources and the environmental impact of energy consumption, particularly energy use in buildings, have awakened considerable interest in energy efficiency. Building energy codes have recently become effective techniques to achieve efficiency targets. The Electricity and Water Authority in Bahrain has set a target of 40% reduction of building electricity consumption and CO 2 emissions to be achieved by using envelope thermal insulation codes. This paper investigates the ability of the current codes to achieve such a benchmark and evaluates their impact on building energy consumption. The results of a simulation study are employed to investigate the impact of the Bahraini codes on the energy and environmental performance of buildings. The study focuses on air-conditioned commercial buildings and concludes that envelope codes, at best, are likely to reduce the energy use of the commercial sector by 25% if the building envelope is well-insulated and efficient glazing is used. Bahraini net CO 2 emissions could drop to around 7.1%. The simulation results show that the current energy codes alone are not sufficient to achieve a 40% reduction benchmark, and therefore, more effort should be spent on moving towards a more comprehensive approach

Building Envelope Thermal Performance Assessment Using Visual Programming and BIM, based on ETTV requirement of Green Mark and GreenRE

Directory of Open Access Journals (Sweden)

Taki Eddine Seghier

2017-09-01

Full Text Available Accomplishment of green building design requirements and the achievement of the targeted credit points under a specific green rating system are known to be a task that is very challenging. Building Information Modeling (BIM design process and tools have already made considerable advancements in green building design and performance analysis. However, Green building design process is still lack of tools and workflows that can provide real-time feedback of building sustainability and rating during the design stage. In this paper, a new workflow of green building design assessment and rating is proposed based on the integration of Visual Programing Language (VPL and BIM. Thus, the aim of this study is to develop a BIM-VPL based tool for building envelope design and assessment support. The focus performance metric in this research is building Envelope Thermal Transfer Value (ETTV which is an Energy Efficiency (EE prerequisite requirement (up to 15 credits in both Green Mark and GreenRE rating systems. The development of the tool begins first by creating a generic integration framework between BIM-VPL functionalities and ETTV requirements. Then, data is extracted from the BIM 3D model and managed using Revit, Excel and Dynamo for visual scripting. A sample project consisting of a hypothetical residential building is run and its envelope ETTV performance and rating score are obtained for the validation of the tool. This tool will support project team in building envelope design and assessment by allowing them to select the most appropriate façade configuration according to its performance efficiency and the green rating. Furthermore, this tool serves as proof of concept that building sustainability rating and compliance checking can be automatically processed through customized workflows developed based on BIM and VPL technologies.

Energy Saving Potentials of Phase Change Materials Applied to Lightweight Building Envelopes

Directory of Open Access Journals (Sweden)

Yoon-Bok Seong

2013-10-01

Full Text Available Phase change materials (PCMs have been considered as an innovative technology that can reduce the peak loads and heating, ventilating and air conditioning (HVAC energy consumption in buildings. Basically they are substances capable of storing or releasing thermal energy as latent heat. Because the amount of latent heat absorbed or released is much larger than the sensible heat, the application of PCMs in buildings has significant potential to reduce energy consumption. However, because each PCM has its own phase change temperature, which is the temperature at which latent heat is absorbed or released, it is important to use an appropriate PCM for the purpose of building envelope design. Therefore, this paper aims to investigate the energy saving potentials in buildings when various PCMs with different phase change temperatures are applied to a lightweight building envelope by analyzing the thermal load characteristics. As results, the annual heating load increased at every phase change temperature, but the peak heating load decreased by 3.19% with heptadecane (phase change temperature 21 °C, and the lowest indoor temperature increased by 0.86 °C with heptadecane (phase change temperature 21 °C. The annual cooling load decreased by 1.05% with dodecanol (phase change temperature 24 °C, the peak cooling load decreased by 1.30% with octadecane (phase change temperature 29 °C, and the highest indoor temperature dropped by 0.50 °C with octadecane (phase change temperature 29 °C. When the night ventilation was applied to the building HVAC system for better passive cooling performance, the annual cooling load decreased by 9.28% with dodecanol (phase change temperature 24 °C, the peak load decreased by 11.33% with octadecane (phase change temperature 29 °C, and the highest indoor temperature dropped by 0.85 °C with octadecane (phase change temperature 29 °C.

Comparative effects of building envelope improvements and occupant behavioural changes on the exergy consumption for heating and cooling

International Nuclear Information System (INIS)

Schweiker, Marcel; Shukuya, Masanori

2010-01-01

Much focus is put on measures to improve the building envelope system performance to reduce the impact of the building sector on the global environmental degradation. This paper compares the potential of building envelope improvements to those of a change in the occupant's behavioural pattern. Three cases of improvements together with a base case were analysed using exergy analysis, because the exergy concept is useful to understand the underlying processes and the necessary adjustments to the calculation of the heat-pump system. The assumptions for the occupant behaviour were set up based on our field measurements conducted in a dormitory building and the calculation was for steady-state conditions. It was found that the potential of occupant behavioural changes for the reduction in exergy consumption is more affected by the outdoor temperature compared to building envelope improvements. The influence of occupant behaviour was highly significant (more than 90% decrease of exergy consumption) when the temperature difference between indoors and outdoors is small, which is the case for long periods in regions with moderate temperatures during summer and/or winter. Nevertheless, both measures combined lead to a reduction from 76% up to 95% depending on the outside conditions and should be the final goal.

Multi-objective and multidisciplinary design optimization of large sports building envelopes : A case study

NARCIS (Netherlands)

Yang, D.; Sun, Y.; Turrin, M.; von Buelow, P.; Paul, J.C.

2015-01-01

Currently, in the conceptual envelope design of sports facilities, multiple engineering performance feedbacks (e.g. daylight, energy and structural performance) are expected to assist architectural design decision-making. In general, it is known as Building Performance Optimization in the conceptual

Alternative methods for evaluation of airtightness of the building envelope; Alternativa metoder foer utvaerdering av byggnadsskalets lufttaethet

Energy Technology Data Exchange (ETDEWEB)

Sikander, Eva; Wahlgren, Paula

2008-07-01

Airtightness plays an important role when constructing energy efficient, sustainable and healthy buildings. In order to obtain airtight buildings, the airtightness needs to be evaluated during the construction phase. This enables improvements of the airtightness in an easy and cost-efficient way. During the construction phase, it is difficult to quantify the airtightness. However, detecting and sealing air leakages are good measures to improve the airtightness of the building. Several methods to detect air leakages are presented. A methodology to search for air leakages in buildings during construction has been developed, together with contractors and experts, and the methodology has been used at two building sites. The quantifiable airtightness of a building is determined by measuring the airflow that enters or exits the building at a certain pressure difference over the building envelope. In some cases it is not possible to measure air tightness according to standard. Therefore, a number of alternative methods have been evaluated. These methods include: extrapolation of measured data to a range used in standard measurements, using a buildings ventilation system fans to create a pressure difference over the building envelope, measuring the airtightness of a smaller part of the building (apartment, fire compartment or component) and tracer gas measurements

Design of the Building Envelope: A Novel Multi-Objective Approach for the Optimization of Energy Performance and Thermal Comfort

Directory of Open Access Journals (Sweden)

Fabrizio Ascione

2015-08-01

Full Text Available According to the increasing worldwide attention to energy and the environmental performance of the building sector, building energy demand should be minimized by considering all energy uses. In this regard, the development of building components characterized by proper values of thermal transmittance, thermal capacity, and radiative properties is a key strategy to reduce the annual energy need for the microclimatic control. However, the design of the thermal characteristics of the building envelope is an arduous task, especially in temperate climates where the energy demands for space heating and cooling are balanced. This study presents a novel methodology for optimizing the thermo-physical properties of the building envelope and its coatings, in terms of thermal resistance, capacity, and radiative characteristics of exposed surfaces. A multi-objective approach is adopted in order to optimize energy performance and thermal comfort. The optimization problem is solved by means of a Genetic Algorithm implemented in MATLAB®, which is coupled with EnergyPlus for performing dynamic energy simulations. For demonstration, the methodology is applied to a residential building for two different Mediterranean climates: Naples and Istanbul. The results show that for Naples, because of the higher incidence of cooling demand, cool external coatings imply significant energy savings, whereas the insulation of walls should be high but not excessive (no more than 13–14 cm. The importance of high-reflective coating is clear also in colder Mediterranean climates, like Istanbul, although the optimal thicknesses of thermal insulation are higher (around 16–18 cm. In both climates, the thermal envelope should have a significant mass, obtainable by adopting dense and/or thick masonry layers. Globally, a careful design of the thermal envelope is always necessary in order to achieve high-efficiency buildings.

Selection of the Climate Parameters for a Building Envelopes and Indoor Climate Systems Design

Directory of Open Access Journals (Sweden)

Oleg Samarin

2017-09-01

Full Text Available The current research considers the principles of selection of the climate information needed for the building envelope and indoor climate design and adopted in Russia and some European countries. Special reference has been made to the shortcoming of methodologies that include the notion of a typical year, and the advantages of climate data sets generated via software-based designs, using pseudo-random number generators. The results of the average temperature of the coldest five-day period with various supplies were calculated using the numerical Monte-Carlo simulations, as well as the current climate data. It has been shown that there is a fundamental overlap between the statistical distribution of temperatures of both instances and the possibility of implementation a probabilistic-statistical method principle in the development of certain climate data, relative to envelopes and thermal conditions of a building. The calculated values were combined with the analytic expression of the normal law of random distribution and the correlations needed for the main parameter selection.

Benchmarking the energy performance of office buildings: A data envelopment analysis approach

Directory of Open Access Journals (Sweden)

Molinos-Senante, María

2016-12-01

Full Text Available The achievement of energy efficiency in buildings is an important challenge facing both developed and developing countries. Very few papers have assessed the energy efficiency of office buildings using real data. To overcome this limitation, this paper proposes an energy efficiency index for buildings having a large window-to-wall ratio, and uses this index to identify the main architectural factors affecting energy performance. This paper assesses, for the first time, the energy performances of 34 office buildings in Santiago, Chile, by using data envelopment analysis. Overall energy efficiency is decomposed into two indices: the architectural energy efficiency index, and the management energy efficiency index. This decomposition is an essential step in identifying the main drivers of energy inefficiency and designing measures for improvement. Office buildings examined here have significant room for improving their energy efficiencies, saving operational costs and reducing greenhouse gas emissions. The methodology and results of this study will be of great interest to building managers and policymakers seeking to increase the sustainability of cities.

Format for description of building envelope components for use in an optimization process

DEFF Research Database (Denmark)

Rudbeck, Claus Christian; Svendsen, Sv Aa Højgaard

1999-01-01

are decided by the architect or kept within limits due to public regulations, but even when these factors have been decided, some are left to be decided. Aspects like durability and the thermal performance are seldom specified by the architect, but might be addressed in national building codes. The national...... building codes specify minimum requirements for the aspects in question, but no trade-offs between the different aspects are allowed, being un-flexible. To allow for the use of optimization procedures in the design process a larger degree of flexibility is needed but first of all there is a need......When designing a building the number of possible combinations of aspects related to the performance of the building envelope are almost unlimited. Due to the physical laws governing e.g. the static performance of the building, some aspects should be kept within a certain interval. Other aspects...

A multi-objective optimization model for energy-efficiency building envelope retrofitting plan with rooftop PV system installation and maintenance

International Nuclear Information System (INIS)

Fan, Yuling; Xia, Xiaohua

2017-01-01

Highlights: • A multi-objective optimization model for building envelope retrofit is presented. • Facility performance degradation and maintenance is built into the model. • A rooftop PV system is introduced to produce electricity. • Economic factors including net present value and payback period are considered. - Abstract: Retrofitting existing buildings with energy-efficient facilities is an effective method to improve their energy efficiency, especially for old buildings. A multi-objective optimization model for building envelope retrofitting is presented. Envelope components including windows, external walls and roofs are considered to be retrofitted. Installation of a rooftop solar panel system is also taken into consideration in this study. Rooftop solar panels are modeled with their degradation and a maintenance scheme is studied for sustainability of energy and its long-term effect on the retrofitting plan. The purpose is to make the best use of financial investment to maximize energy savings and economic benefits. In particular, net present value, the payback period and energy savings are taken as the main performance indicators of the retrofitting plan. The multi-objective optimization problem is formulated as a non-linear integer programming problem and solved by a weighted sum method. Results of applying the designed retrofitting plan to a 50-year-old building consisting of 66 apartments demonstrated the effectiveness of the proposed model.

Methodology for the Study of the Envelope Airtightness of Residential Buildings in Spain: A Case Study

Directory of Open Access Journals (Sweden)

Feijó-Muñoz Jesús

2018-03-01

Full Text Available Air leakage and its impact on the energy performance of dwellings has been broadly studied in countries with cold climates in Europe, US, and Canada. However, there is a lack of knowledge in this field in Mediterranean countries. Current Spanish building regulations establish ventilation rates based on ideal airtight envelopes, causing problems of over-ventilation and substantial energy losses. The aim of this paper is to develop a methodology that allows the characterization of the envelope of the housing stock in Spain in order to adjust ventilation rates taking into consideration air leakage. A methodology that is easily applicable to other countries that consider studying the airtightness of the envelope and its energetic behaviour improvement is proposed. A statistical sampling method has been established to determine the dwellings to be tested, considering relevant variables concerning airtightness: climate zone, year of construction, and typology. The air leakage rate is determined using a standardized building pressurization technique according to European Standard EN 13829. A representative case study has been presented as an example of the implementation of the designed methodology and results are compared to preliminary values obtained from the database.

Researching Complex Heat, Air and Moisture Interactions for a Wide-Range of Building Envelope Systems and Environmental Loads

Energy Technology Data Exchange (ETDEWEB)

Karagiozis, A.N.

2007-05-15

This document serves as the final report documenting work completed by Oak Ridge National Laboratory (ORNL) and the Fraunhofer Institute in Building Physics (Holzkirchen, Germany) under an international CRADA No. 0575 with Fraunhofer Institute of Bauphysics of the Federal Republic of Germany for Researching Complex Heat, Air and Moisture Interactions for a Wide Range of Building Envelope Systems and Environmental Loads. This CRADA required a multi-faceted approach to building envelope research that included a moisture engineering approach by blending extensive material property analysis, laboratory system and sub-system thermal and moisture testing, and advanced moisture analysis prediction performance. The Participant's Institute for Building physics (IBP) and the Contractor's Buildings Technology Center (BTC) identified potential research projects and activities capable of accelerating and advancing the development of innovative, low energy and durable building envelope systems in diverse climates. This allowed a major leverage of the limited resources available to ORNL to execute the required Department of Energy (DOE) directives in the area of moisture engineering. A joint working group (ORNL and Fraunhofer IBP) was assembled and a research plan was executed from May 2000 to May 2005. A number of key deliverables were produced such as adoption of North American loading into the WUFI-software. in addition the ORNL Weather File Analyzer was created and this has been used to address environmental loading for a variety of US climates. At least 4 papers have been co-written with the CRADA partners, and a chapter in the ASTM Manual 40 on Moisture Analysis and Condensation Control. All deliverables and goals were met and exceeded making this collaboration a success to all parties involves.

Operative air temperature data for different measures applied on a building envelope in warm climate

Directory of Open Access Journals (Sweden)

Cristina Baglivo

2018-04-01

Full Text Available Several technical combinations have been evaluated in order to design high energy performance buildings for the warm climate. The analysis has been developed in several steps, avoiding the use of HVAC systems.The methodological approach of this study is based on a sequential search technique and it is shown on the paper entitled “Envelope Design Optimization by Thermal Modeling of a Building in a Warm Climate” [1].The Operative Air Temperature trends (TOP, for each combination, have been plotted through a dynamic simulation performed using the software TRNSYS 17 (a transient system simulation program, University of Wisconsin, Solar Energy Laboratory, USA, 2010.Starting from the simplest building configuration consisting of 9 rooms (equal-sized modules of 5 × 5 m2, the different building components are sequentially evaluated until the envelope design is optimized. The aim of this study is to perform a step-by-step simulation, simplifying as much as possible the model without making additional variables that can modify their performances. Walls, slab-on-ground floor, roof, shading and windows are among the simulated building components. The results are shown for each combination and evaluated for Brindisi, a city in southern Italy having 1083 degrees day, belonging to the national climatic zone C. The data show the trends of the TOP for each measure applied in the case study for a total of 17 combinations divided into eight steps.

Energy performance and optimal control of air-conditioned buildings with envelopes enhanced by phase change materials

International Nuclear Information System (INIS)

Zhu Na; Wang Shengwei; Ma Zhenjun; Sun Yongjun

2011-01-01

Highlights: → Impact of PCM on the energy consumption and peak load demand as well as electricity cost of air-conditioned buildings. → Impact of load shifting control on energy consumption, peak load and electricity cost of air-conditioned PCM buildings. → Impact of demand limiting control on energy consumption, peak load and electricity cost of air-conditioned PCM buildings. → Energy/cost effects of different control strategies and use of PCM in energy-plus-demand-based pricing policy. → Energy/cost effects of different control strategies and use of PCM in time-based pricing policy. - Abstract: Studies are conducted to investigate the impacts of shape-stabilized phase change material (SSPCM) and different control strategies on the energy consumption and peak load demand as well as electricity cost of building air-conditioning systems at typical summer conditions in two climates (subtropical and dry continental climates). An office building using a typical variable air volume (VAV) air-conditioning system was selected and simulated as the reference building in this study. Its envelopes were enhanced by integrating the SSPCM layers into its walls while the air-conditioning system and other configurations of the building remained unchanged. The building system was tested under two typical weather conditions and two typical electricity pricing policies (i.e. time-based pricing and energy-plus-demand-based pricing). Test results show that the use of SSPCM in the building could reduce the building electricity cost significantly (over 11% in electricity cost reduction and over 20% in peak load reduction), under two pricing policies by using load shifting control and demand limiting control respectively. This paper presents the test results and the evaluation on the energy performance and the optimal control strategies of air-conditioned commercial buildings with envelopes enhanced by SSPCM.

Preserving Envelope Efficiency in Performance Based Code Compliance

Energy Technology Data Exchange (ETDEWEB)

Thornton, Brian A. [Thornton Energy Consulting (United States); Sullivan, Greg P. [Efficiency Solutions (United States); Rosenberg, Michael I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Baechler, Michael C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-06-20

The City of Seattle 2012 Energy Code (Seattle 2014), one of the most progressive in the country, is under revision for its 2015 edition. Additionally, city personnel participate in the development of the next generation of the Washington State Energy Code and the International Energy Code. Seattle has pledged carbon neutrality by 2050 including buildings, transportation and other sectors. The United States Department of Energy (DOE), through Pacific Northwest National Laboratory (PNNL) provided technical assistance to Seattle in order to understand the implications of one potential direction for its code development, limiting trade-offs of long-lived building envelope components less stringent than the prescriptive code envelope requirements by using better-than-code but shorter-lived lighting and heating, ventilation, and air-conditioning (HVAC) components through the total building performance modeled energy compliance path. Weaker building envelopes can permanently limit building energy performance even as lighting and HVAC components are upgraded over time, because retrofitting the envelope is less likely and more expensive. Weaker building envelopes may also increase the required size, cost and complexity of HVAC systems and may adversely affect occupant comfort. This report presents the results of this technical assistance. The use of modeled energy code compliance to trade-off envelope components with shorter-lived building components is not unique to Seattle and the lessons and possible solutions described in this report have implications for other jurisdictions and energy codes.

Influence of PCMs in thermal insulation on thermal behaviour of building envelopes

Science.gov (United States)

Dydek, K.; Furmański, P.; Łapka, P.

2016-09-01

A model of heat transfer through a wall consisting of a layer of concrete and PCM enhanced thermal insulation is considered. The model accounts for heat conduction in both layers, thermal radiation and heat absorption/release due to phase change in the insulation as well as time variation in the ambient temperature and insolation. Local thermal equilibrium between encapsulated PCM and light-weight thermal insulation was assumed. Radiation emission, absorption and scattering were also accounted for in the model. Comparison of different cases of heat flow through the building envelope was carried out. These cases included presence or absence of PCM and thermal radiation in the insulation, effect of emissivity of the PCM microcapsules as well as an effect of solar radiation or its lack on the ambient side of the envelope. Two ways of the PCM distribution in thermal insulation were also considered. The results of simulations were presented for conditions corresponding to the mean summer and winter seasons in Warsaw. It was found that thermal radiation plays an important role in heat transfer through thermal insulation layer of the wall while the presence of the PCM in it significantly contributes to damping of temperature fluctuations and a decrease in heat fluxes flowing into or lost by the interior of the building. The similar effect was observed for a decrease in emissivity of the microcapsules containing PCM.

Methods for designing building envelope components prepared for repair and maintenance

DEFF Research Database (Denmark)

Rudbeck, Claus Christian

2000-01-01

the deterministic and probabilistic approach. Based on an investigation of the data-requirement, user-friendliness and supposed accuracy (the accuracy of the different methods has not been evaluated due to the absence of field data) the method which combines the deterministic factor method with statistical...... to be prepared for repair and maintenance. Both of these components are insulation systems for flat roofs and low slope roofs; components where repair or replacement is very expensive if the roofing material fails in its function. The principle of both roofing insulation systems is that the insulation can...... of issues which are specified below:Further development of methods for designing building envelope components prepared for repair and maintenance, and ways of tracking and predicting performance through time once the components have been designed, implemented in a building design and built...

Microclimatic conditions at the external surface of building envelopes

Energy Technology Data Exchange (ETDEWEB)

Kragh, M.K.

1998-12-31

The project is described, the motivation for the research and the microclimate is defined in relation to both building physics research and applications. Air temperatur, air humidity, solar radiation and air velocity are briefly considered, whilst driving rain and long-wave radiation are described in more detail. Convective heat transfer and surface coefficients are discussed, although they are not microclimatic factors, merely resulting from combinations of such factors. They are included as they are important in relation to transfer of heat and moisture at the surface of the building envelope. Driving rain measurement is the main area of interest, including development of measurement equipment. Long-wave irradiation is measured and compared with empirical formulae from the literature. Window convection heat transfer is another main area of interest. Nocturnal convective heat transfer from a double pane glazing is studied and measurement principles are discussed. Finally, a compilation of meteorological data for hygrothermal simulations, including estimation of driving rain, is described. System error estimation in relation to the window convection measurements, design notes on an apparatus for external convection measurement, formulae for conversion of relative humitity and dry-bulb temperature into dew point temperature. (EG) 66 refs.

Microclimatic conditions at the external surface of building envelopes

Energy Technology Data Exchange (ETDEWEB)

Kragh, M K

1999-12-31

The project is described, the motivation for the research and the microclimate is defined in relation to both building physics research and applications. Air temperatur, air humidity, solar radiation and air velocity are briefly considered, whilst driving rain and long-wave radiation are described in more detail. Convective heat transfer and surface coefficients are discussed, although they are not microclimatic factors, merely resulting from combinations of such factors. They are included as they are important in relation to transfer of heat and moisture at the surface of the building envelope. Driving rain measurement is the main area of interest, including development of measurement equipment. Long-wave irradiation is measured and compared with empirical formulae from the literature. Window convection heat transfer is another main area of interest. Nocturnal convective heat transfer from a double pane glazing is studied and measurement principles are discussed. Finally, a compilation of meteorological data for hygrothermal simulations, including estimation of driving rain, is described. System error estimation in relation to the window convection measurements, design notes on an apparatus for external convection measurement, formulae for conversion of relative humitity and dry-bulb temperature into dew point temperature. (EG) 66 refs.

Integrated energy design of the building envelope

Energy Technology Data Exchange (ETDEWEB)

Vraa Nielsen, M.

2012-07-01

This thesis describes the outcome of the PhD project Integrated energy design of the building envelope carried out through a combination of scientific dissemination reported through peer-reviewed journals and a wide range of affiliated projects involved in at an architectural firm. The research project analysed how the implementation of technical knowledge early in the building design process can quantify the effect of a building's facades on its energy efficiency and indoor climate and thereby facilitate a more qualified design development. The project was structured in the following way: 1) the importance of integrating knowledge in the early stages of design, and how it can be done; 2) understanding the facade's typology; and 3) the complex notion of comfort. The project touched not only on the technical capabilities and requirements governing facade design, but also the process by which it takes place. This was done by applying the methodology of Integrated Energy Design (IED) and analysing its applicability in the design of facades. A major part of the project was an actual engagement in the architectural process to test out incorporating a consciousness about energy and comfort as part of a more holistic performance evaluation. The research project illustrates the great potential in taking passive properties into account through a geometrical optimisation inherent in the development of the architectural concept. It demonstrates that integration of technical knowledge at the early stages of design not only can qualify the geometrical processing, but also facilitate the design development of the facade. Thereby a more holistic performance optimisation can be obtained through parameters such as overall facade geometry and orientation, functional organisation, room height and depth, facade layout, window geometry and transparency, design of the window aperture, etc. Through the wide range of affiliated project involved in at the architectural firm over

Optimum Application of Thermal Factors to Artificial Neural Network Models for Improvement of Control Performance in Double Skin-Enveloped Buildings

Directory of Open Access Journals (Sweden)

Kyung-Il Chin

2013-08-01

Full Text Available This study proposes an artificial neural network (ANN-based thermal control method for buildings with double skin envelopes that has rational relationships between the ANN model input and output. The relationship between the indoor air temperature and surrounding environmental factors was investigated based on field measurement data from an actual building. The results imply that the indoor temperature was not significantly influenced by vertical solar irradiance, but by the outdoor and cavity temperature. Accordingly, a new ANN model developed in this study excluded solar irradiance as an input variable for predicting the future indoor temperature. The structure and learning method of this new ANN model was optimized, followed by the performance tests of a variety of internal and external envelope opening strategies for the heating and cooling seasons. The performance tests revealed that the optimized ANN-based logic yielded better temperature conditions than the non-ANN based logic. This ANN-based logic increased overall comfortable periods and decreased the frequency of overshoots and undershoots out of the thermal comfort range. The ANN model proved that it has the potential to be successfully applied in the temperature control logic for double skin-enveloped buildings. The ANN model, which was proposed in this study, effectively predicted future indoor temperatures for the diverse opening strategies. The ANN-based logic optimally determined the operation of heating and cooling systems as well as opening conditions for the double skin envelopes.

Isostatic lines’ study to optimize steel space grid envelope structures for tall buildings according to their solicitations

OpenAIRE

Señís López, Roger

2013-01-01

Based on the first study completed with wind tunnel tests, the aim of this paper is to define a second methodology for the optimization of steel space grid envelope structures for tall buildings according to their isostatic lines according to their solicitations. It is by means of the comparison NatHaz online database and numerical simulation research of wind flow repercussion in buildings, through Computational Fluid Dynamics (CDF), that we can understand and analyse the grid ...

Thermoelectricity analogy method for computing the periodic heat transfer in external building envelopes

International Nuclear Information System (INIS)

Peng Changhai; Wu Zhishen

2008-01-01

Simple and effective computation methods are needed to calculate energy efficiency in buildings for building thermal comfort and HVAC system simulations. This paper, which is based upon the theory of thermoelectricity analogy, develops a new harmonic method, the thermoelectricity analogy method (TEAM), to compute the periodic heat transfer in external building envelopes (EBE). It presents, in detail, the principles and specific techniques of TEAM to calculate both the decay rates and time lags of EBE. First, a set of linear equations is established using the theory of thermoelectricity analogy. Second, the temperature of each node is calculated by solving the linear equations set. Finally, decay rates and time lags are found by solving simple mathematical expressions. Comparisons show that this method is highly accurate and efficient. Moreover, relative to the existing harmonic methods, which are based on the classical control theory and the method of separation of variables, TEAM does not require complicated derivation and is amenable to hand computation and programming

Reuse and Upcycling of Municipal Waste for ZEB Envelope Design in European Urban Areas

Directory of Open Access Journals (Sweden)

Elisa Pennacchia

2016-06-01

Full Text Available Building energy efficiency and urban waste management are two focal issues for improving environmental status and reducing greenhouse gas emissions. The main aim of this paper is to compare economic costs of new building envelope structures designed by authors reusing and upcycling municipal waste in order to decrease energy demand from the building sector and, at the same time, improve eco-friendly waste management at the local scale. The reuse of waste for building envelope structures is one of the main principles of the Earthship buildings model, based on the use of passive solar principles in autonomous earth-sheltered homes. This Earthship principle has been analyzed in order to optimize buildings’ energy performance and reuse municipal waste for new building envelope structures in urban areas. Indeed, the elaborated structures have been designed for urban contexts, with the aim of reuse waste coming from surrounding landfills. The methods include an analysis of thermal performance of urban waste for designing new building envelope structures realized by assembling waste and isolating materials not foreseen in Earthship buildings. The reused materials are: cardboard tubes, automobile tires, wood pallets, and plastic and glass bottles. Finally, comparing economic costs of these new building envelope structures, the obtained results highlight their economic feasibility compared to a traditional structure with similar thermal transmittance.

Integrated Thermal-Energy Analysis of Innovative Translucent White Marble for Building Envelope Application

Directory of Open Access Journals (Sweden)

Federica Rosso

2014-08-01

Full Text Available Marble is a natural material, used in the construction field since antiquity. It has always been used to communicate monumentality and solidity. Nowadays new technologies permit marble to express new languages: particularly, translucent marble technology overturns the concept of solidity. The main issue to address is the lack of thermal-energy performance of such a thin stone layer as the only facade component. Conversely, Bianco Carrara and Statuario marbles, for instance, have intrinsic benefits as natural cool materials, due to their high solar reflectance and thermal emissivity. Thus, this paper analyzes the thermal-energy and environmental behavior of marble facade for a new designed building in New York City. An integrated analysis of the energy performance of the marble skin is performed through a preliminary experimental characterization, carried out for two different types of naturally white marble, for comparative purposes. Then, a dynamic simulation model of the building is developed to evaluate year-round benefits and drawbacks of the translucent marble envelope in terms of indoor thermal comfort and air-conditioning requirement. The analysis showed how the proposed marble facade is able to decrease the energy requirement for cooling up to 6%, demonstrating possible relevant perspectives for marble-based facades, even in energy-efficient buildings.

Innovative Danish Building Envelope Components for Passive Houses

DEFF Research Database (Denmark)

Tommerup, Henrik M.; Svendsen, Svend

2006-01-01

and in some cases very innovative envelope constructions. In this paper, two of the most interesting components are described; a prefabricated light-weight exterior wall element with a load-bearing plywood and steel frame and a foundation / slab on ground solution based on concrete and EPS insulation...

Energy management systems in buildings

Energy Technology Data Exchange (ETDEWEB)

Lush, D. M.

1979-07-01

An investigation is made of the range of possibilities available from three types of systems (automatic control devices, building envelope, and the occupants) in buildings. The following subjects are discussed: general (buildings, design and personnel); new buildings (envelope, designers, energy and load calculations, plant design, general design parameters); existing buildings (conservation measures, general energy management, air conditioned buildings, industrial buildings); man and motivation (general, energy management and documentation, maintenance, motivation); automatic energy management systems (thermostatic controls, optimized plant start up, air conditioned and industrial buildings, building automatic systems). (MCW)

Solar envelope zoning: application to the city planning process. Los Angeles case study

Energy Technology Data Exchange (ETDEWEB)

1980-06-01

Solar envelope zoning represents a promising approach to solar access protection. A solar envelope defines the volume within which a building will not shade adjacent lots or buildings. Other solar access protection techniques, such as privately negotiated easements, continue to be tested and implemented but none offer the degree of comprehensiveness evident in this approach. Here, the City of Los Angeles, through the Mayor's Energy Office, the City Planning Department, and the City Attorney's Office, examine the feasibility of translating the concept of solar envelopes into zoning techniques. They concluded that envelope zoning is a fair and consistent method of guaranteeing solar access, but problems of complexity and uncertainty may limit its usefulness. Envelope zoning may be inappropriate for the development of high density centers and for more restrictive community plans. Aids or tools to administer envelope zoning need to be developed. Finally, some combination of approaches, including publicly recorded easements, subdivision approval and envelope zoning, need to be adopted to encourage solar use in cities. (MHR)

Research on Energy-Saving Optimization for the Performance Parameters of Rural-Building Shape and Envelope by TRNSYS-GenOpt in Hot Summer and Cold Winter Zone of China

Directory of Open Access Journals (Sweden)

Shilei Lu

2017-02-01

Full Text Available The aim of this paper is to optimize the building shape parameters and envelope parameters influencing the rural building energy consumption in cold winter and hot summer climate. Several typical models are established and optimized by integrated TRNSYS and GenOpt. Single-objective optimization has provided guidance to the multi-dimensional optimization. Building shape and envelope parameters are considered simultaneously by multi-dimensional optimization. Results of the optimization showed significant reduction in terms of EC (energy consumption. When O (building orientation was SW (south by west 10°, LWR (length-width ratio was 1.1, WWRS (window-wall ratio in south with the range of 0.6–0.8, ITE (insulation thickness of exterior wall and ITR (insulation thickness of roof was 0.05 m and 0.08 m respectively, the building had minimal energy consumption. The results also indicated that the optimal EWT (exterior window type was plastic single-frame Low-E insulating glazing filled with inert gas, and the optimal shape of building is Re (rectangle. An effective method was provided to optimize the design of the rural building for the purpose of reducing building energy consumption in cold winter and hot summer climate.

Pre-paid envelopes commemorating the 2013 Open Days

CERN Multimedia

2013-01-01

The post office on CERN's Prévessin site is still selling pre-paid envelopes commemorating the 2013 Open Days. Hurry while stocks last!   The special envelopes, which are valid in France for non-priority letters weighing up to 20 grams, are ideal for your Christmas and New Year correspondence. A set of ten envelopes, each featuring a different image, costs € 8.70 or 10 CHF. The post office is located in Building 866 on the Prévessin site and is open Mondays to Thursdays from 9.30 a.m. to 12.30 p.m.

Integrating Environmentally Responsive Elements in Buildings

DEFF Research Database (Denmark)

Heiselberg, Per

2006-01-01

Significant improvement have been achieved on efficiency improvements of specific building elements like the building envelope and building equipment and services and whilst most building elements still offer opportunities for efficiency improvements, the greatest future potential lie with techno......Significant improvement have been achieved on efficiency improvements of specific building elements like the building envelope and building equipment and services and whilst most building elements still offer opportunities for efficiency improvements, the greatest future potential lie...

The performance of a novel flat heat pipe based thermal and PV/T (photovoltaic and thermal systems) solar collector that can be used as an energy-active building envelope material

International Nuclear Information System (INIS)

Jouhara, H.; Milko, J.; Danielewicz, J.; Sayegh, M.A.; Szulgowska-Zgrzywa, M.; Ramos, J.B.; Lester, S.P.

2016-01-01

A novel flat heat pipe design has been developed and utilised as a building envelope and thermal solar collector with and without (PV) bonded directly to its surface. The design of the new solar collector has been validated through full scale testing in Cardiff, UK where solar/thermal, uncooled PV and PV/T tests were carried out on three identical systems, simultaneously. The tests showed a solar/thermal energy conversion efficiency of around 64% for the collector with no PV and 50% for the system with the PV layer on it. The effect of cooling on the solar/electrical energy conversion efficiency was also investigated and an efficiency increase of about 15% was recorded for the cooled PV system due to the provided homogenous cooling. The new flat heat pipe solar collector is given the name “heat mat” and, in addition to being an efficient solar collector type, it is also designed to convert a building envelope materials to become energy-active. A full size roof that utilise this new building envelope material is reported in this paper to demonstrate the way this new collector is integrated as a building envelope material to form a roof. A thermal absorption test, in a controlled environment, from the ambient to the heat mat with no solar radiation is also reported. The test has proved the heat mat as an efficient thermal absorber from the ambient to the intermediate fluid that deliver the heat energy to the heat pump system. - Highlights: • A new flat heat pipe PV/T system that can be used as building materials is reported. • The new solar collector enhanced the performance of the PV by about 15%. • The new solar collector is capable of absorbing heat from ambient efficiently. • The new system is efficient from the solar/thermal conversion point of view.

On Innovative Cool-Colored Materials for Building Envelopes: Balancing the Architectural Appearance and the Thermal-Energy Performance in Historical Districts

Directory of Open Access Journals (Sweden)

Federica Rosso

2017-12-01

Full Text Available Architectural expression and energy performance are key decision-drivers in the selection of a particular construction element, with the purpose of Urban Heat Island mitigation, energy-consumption reductions, and cultural heritage preservation in historical centers. In historical centers, the external layer of the envelope and the visible parts of the building are built with traditional materials and technological solutions, such as single-layer walls or brickworks, depending on the country’s context, while the energy performance is usually optimized by means of internal insulation layers, or other active and passive solutions. Thermal-energy efficient materials and construction elements for the temperate, warm climate of the Mediterranean area are usually light-colored to reflect the largest part of solar radiation, thus reducing energy demands for cooling and improving thermal comfort conditions for occupants. On the other hand, many historical centers in such areas are characterized by reddish or grayish colors. In this work, we considered Italian historical areas, and other countries in the Mediterranean area with present similar situations. Thus, in this study, innovative, cool-colored, cement-based materials were developed to improve the thermal-energy performance of the external envelope of historical/historic built environments, without altering their appearance. These materials were prepared directly on-site, by mixing two types of pigments to achieve the desired color saturation. Optic and thermal properties were assessed, and yearly dynamic simulations of a historic, listed, case study building were performed, by comparing traditional-colored mortar and the prototype cool mortar envelopes. The research demonstrates that such cool-colored materials can maintain lower surface temperatures (−8 °C, while reducing energy demands for cooling (−3%.

A multi-criteria model for the comparison of building envelope energy retrofits

Science.gov (United States)

Donnarumma, Giuseppe; Fiore, Pierfrancesco

2017-02-01

In light of the current EU guidelines in the energy field, improving building envelope performance cannot be separated from the context of satisfying the environmental sustainability requirements, reducing the costs associated with the life cycle of the building as well as economic and financial feasibility. Therefore, identifying the "optimal" energy retrofit solutions requires the simultaneous assessment of several factors and thus becomes a problem of choice between several possible alternatives. To facilitate the work of the decision-makers, public or private, adequate decision support tools are of great importance. Starting from this need, a model based on the multi-criteria analysis "AHP" technique is proposed, along with the definition of three synthetic indices associated with the three requirements of "Energy Performance", "Sustainability Performance" and "Cost". From the weighted aggregation of the three indices, a global index of preference is obtained that allows to "quantify" the satisfaction level of the i-th alternative from the point of view of a particular group of decision-makers. The model is then applied, by way of example, to the case-study of the energetic redevelopment of a former factory, assuming its functional conversion. Twenty possible alternative interventions on the opaque vertical closures, resulting from the combination of three thermal insulators families (synthetic, natural and mineral) with four energy retrofitting techniques are compared and the results obtained critically discussed by considering the point of view of the three different groups of decision-makers.

AM Envelope. The potential of Additive Manufacturing for facade constructions

Directory of Open Access Journals (Sweden)

Holger Strauss

2017-11-01

Full Text Available This dissertation shows the potential of Additive Manufacturing (AM for the development of building envelopes: AM will change the way of designing facades, how we engineer and produce them. To achieve today’s demands from those future envelopes, we have to find new solutions. New technologies offer one possible way to do so. They open new approaches in designing, producing and processing building construction and facades. Finding the one capable of having big impact is difficult – Additive Manufacturing is one possible answer. The term ‘AM Envelope’ (Additive Manufacturing Envelope describes the transfer of this technology to the building envelope. Additive Fabrication is a building block that aids in developing the building envelope from a mere space enclosure to a dynamic building envelope. First beginnings of AM facade construction show up when dealing with relevant aspects like material consumption, mounting or part’s performance. From those starting points several parts of an existing post-and-beam façade system were optimized, aiming toward the implementation of AM into the production chain. Enhancements on all different levels of production were achieved: storing, producing, mounting and performance. AM offers the opportunity to manufacture facades ‘just in time’. It is no longer necessary to store or produce large numbers of parts in advance. Initial investment for tooling can be avoided, as design improvements can be realized within the dataset of the AM part. AM is based on ‘tool-less’ production, all parts can be further developed with every new generation. Producing tool-less also allows for new shapes and functional parts in small batch sizes – down to batch size one. The parts performance can be re-interpreted based on the demands within the system, not based on the limitations of conventional manufacturing. AM offers new ways of materializing the physical part around its function. It leads toward customized

An energy efficient building for the Arctic climate

DEFF Research Database (Denmark)

Vladyková, Petra

through the building envelope in the winter due to the pressure difference, strong winds and low water ratio in the outdoor air. The Arctic is also defined by different conditions such as building techniques and availability of the materials and energy supply. The passive house uses the basic idea......The Arctic is climatically very different from a temperate climate. In the Arctic regions, the ambient temperature reaches extreme values and it has a direct large impact on the heat loss through the building envelope and it creates problems with the foundation due to the permafrost. The solar...... influence the infiltration heat loss through the building envelope. The wind patterns have large influences on the local microclimate around the building and create the snowdrift and problems with thawing, icing and possible condensation in the building envelope. The humidity in the interior is driven out...

CISBAT 2005 proceedings. Renewables in a changing climate - Innovation in building envelopes and environmental systems; CISBAT 2005 proceedings. Energies renouvelables et climat - Enveloppes et systemes environnementaux innovatifs

Energy Technology Data Exchange (ETDEWEB)

Scartezzini, J L [ed.

2005-07-01

These proceedings include the contributions presented at the 2005 CISBAT conference, held in Lausanne, Switzerland. Hosted by the Swiss Federal Institute of Technology (EPFL) in Lausanne and jointly organised by the Solar Energy and Buildings Physics Laboratory at the EPFL, Cambridge University and the Massachusetts Institute of Technology (MIT), this international conference looked at 'Innovation in building envelopes and environmental systems'. Along with three keynote presentations on climate change, the use of renewables in the European Union and Swiss policies on solar energy, these 632-page conference proceedings include the conference's 106 presentations grouped in 10 sections. These cover the following topics: Design and renovation of building envelopes (33 contributions); solar collectors (16 contributions); active and passive cooling (9 contributions); indoor environment quality and health (10 contributions); optimisation of daylighting and electric lighting (5 contributions); advanced building control systems (2 contributions); environmental impacts of construction (4 contributions); networks and decentralised energy production (1 contribution); sustainable urban development (12 contributions) and software and new information technologies (14 contributions). Organised each second year, the two-day CISBAT international conference 2005 attracted more than 200 participants from all over the world.

CISBAT 2005 proceedings. Renewables in a changing climate - Innovation in building envelopes and environmental systems; CISBAT 2005 proceedings. Energies renouvelables et climat - Enveloppes et systemes environnementaux innovatifs

Energy Technology Data Exchange (ETDEWEB)

Scartezzini, J. L. (ed.)

2005-07-01

These proceedings include the contributions presented at the 2005 CISBAT conference, held in Lausanne, Switzerland. Hosted by the Swiss Federal Institute of Technology (EPFL) in Lausanne and jointly organised by the Solar Energy and Buildings Physics Laboratory at the EPFL, Cambridge University and the Massachusetts Institute of Technology (MIT), this international conference looked at 'Innovation in building envelopes and environmental systems'. Along with three keynote presentations on climate change, the use of renewables in the European Union and Swiss policies on solar energy, these 632-page conference proceedings include the conference's 106 presentations grouped in 10 sections. These cover the following topics: Design and renovation of building envelopes (33 contributions); solar collectors (16 contributions); active and passive cooling (9 contributions); indoor environment quality and health (10 contributions); optimisation of daylighting and electric lighting (5 contributions); advanced building control systems (2 contributions); environmental impacts of construction (4 contributions); networks and decentralised energy production (1 contribution); sustainable urban development (12 contributions) and software and new information technologies (14 contributions). Organised each second year, the two-day CISBAT international conference 2005 attracted more than 200 participants from all over the world.

Creating a Lunar EVA Work Envelope

Science.gov (United States)

Griffin, Brand N.; Howard, Robert; Rajulu, Sudhakar; Smitherman, David

2009-01-01

A work envelope has been defined for weightless Extravehicular Activity (EVA) based on the Space Shuttle Extravehicular Mobility Unit (EMU), but there is no equivalent for planetary operations. The weightless work envelope is essential for planning all EVA tasks because it determines the location of removable parts, making sure they are within reach and visibility of the suited crew member. In addition, using the envelope positions the structural hard points for foot restraints that allow placing both hands on the job and provides a load path for reacting forces. EVA operations are always constrained by time. Tasks are carefully planned to ensure the crew has enough breathing oxygen, cooling water, and battery power. Planning first involves computers using a virtual work envelope to model tasks, next suited crew members in a simulated environment refine the tasks. For weightless operations, this process is well developed, but planetary EVA is different and no work envelope has been defined. The primary difference between weightless and planetary work envelopes is gravity. It influences anthropometry, horizontal and vertical mobility, and reaction load paths and introduces effort into doing "overhead" work. Additionally, the use of spacesuits other than the EMU, and their impacts on range of motion, must be taken into account. This paper presents the analysis leading to a concept for a planetary EVA work envelope with emphasis on lunar operations. There is some urgency in creating this concept because NASA has begun building and testing development hardware for the lunar surface, including rovers, habitats and cargo off-loading equipment. Just as with microgravity operations, a lunar EVA work envelope is needed to guide designers in the formative stages of the program with the objective of avoiding difficult and costly rework.

Climate Change Adopted Building Envelope as A Protector of Human Health in the Urban Environment

Science.gov (United States)

Januszkiewicz, Krystyna

2017-10-01

Recently, an expanded understanding of building performance acknowledges that all forces acting on buildings (climate, energies, information, and human agents) are not static and fixed, but rather mutable and transient. With the use of parametric and multi-criteria optimization digital tools, buildings’ envelopes can be designed to respond to various requirements. This paper explores the possibilities of architectural design to benefit human conditions, which encompasses mental well-being, environmental quality of life during the Climate Change era. The first part of the paper defines the main factors (such as: lack of green nature and sunlight, noise and pollution) which are influencing the formation of psychological disorder in big cities. The negative impact of these factors is constantly increasing in the time of Climate Change progressing. The second part presents results of the research program undertaken at West Pomeranian University of Technology in Szczecin by author. The program goes on to attempt to solve the problem through architectural design. This study highlights a social problem, such as mental well-being, resulting from urbanization or effects of the climate change, and serves as a useful background for further research on the possibilities of redefining sustainable and human friendly design.

Building integrated photovoltaics

NARCIS (Netherlands)

Ritzen, M.J.; Vroon, Z.A.E.P.; Geurts, C.P.W.; Reinders, Angèle; Verlinden, Pierre; Sark, Wilfried; Freundlich, Alexandre

2017-01-01

Photovoltaic (PV) installations can be realized in different situations and on different scales, such as at a building level. PV installations at the building level can either be added to the building envelope, which is called building added PV (BAPV), or they can be integrated into the building

A new insight into opaque envelopes in a passive solar house: Properties and roles

International Nuclear Information System (INIS)

Long, Linshuang; Ye, Hong; Liu, Minghou

2016-01-01

Highlights: • A new insight into the opaque envelopes of a passive solar house was gained. • Five parts of envelopes, i.e., roof, south/east/west/north walls, were discussed. • Each part of envelopes were analyzed separately rather than treated as a whole. • Ideal properties of materials for each envelope are diverse from one another. • Differences are related to the envelopes’ leading roles as a heater or a cooler. - Abstract: Passive solar houses are effective solutions for minimizing the operating energy of buildings. The building envelopes of passive solar houses exert a significant influence on the degree of indoor thermal comfort. The focus of this study was the construction of high-performance opaque envelopes, i.e., the roof and walls, for a passive solar house, and a new conception of the envelopes from the perspective of the relation between the properties and roles was provided. The discussion was conducted based on a comprehensive range of envelope materials that were distinguished by the thermal conductivity and volumetric heat capacity. For the first time, each part of the envelopes was analyzed separately rather than considered as an entire envelope. By analyzing each envelope individually, the optimum properties of each envelope were found to be distinct from each other. The distinctions are determined by the dominant role of each envelope, which is associated with the location and absorbed solar irradiation. For summer or hot climate applications, when the dominant role is a cooler, the envelope, e.g., the south wall, should consist of materials with high thermal conductivity and large heat capacity; if a heater is the dominant role, the envelope, e.g., the roof, should consist of materials with low thermal conductivity. For winter or cold climate applications, the envelopes with a leading role of a heater or a cooler require materials with high or low thermal conductivity, respectively. Under the guidance of the results, a discussion

Experiences when employing different alternatives for envelope upgrading

Directory of Open Access Journals (Sweden)

Peru Elguezabal Esnarrizaga

2015-06-01

Full Text Available The challenges of achieving the 2020 goals in terms of energy savings and improving efficiency are guiding numerous research initiatives looking for more insulated envelopes, dealing with thermal performance of insulation materials and envelope systems. Nevertheless, the envelope integrates within the building and this improvement on the insulation performance has to be properly adopted, taking into account the interrelation of main elements composing the overall system (facade, frame, slabs, openings, partitions etc., as well as side effects originated not only for new erected buildings, but specifically in renovation and retrofitting works. This paper describes real experiences when considering various options for upgrading the facade through the increase of the insulation capacity, starting from external overcladding prefabricated panels and ventilated facades, advancing to more sustainable low carbon systems and ending with even more highly insulated solutions employing aerogels. Lessons from these cases, where energy and hygrothermal assessments have being carried out, demonstrate the influence of the design and construction phases and the relevance of disregarded effects such as minor thermal bridges, uncontrolled craftsmanship on site, and moisture transfer for the different technologies considered. Finally, possible alternatives are provided to overcome some of the detected difficulties, such as combination with non-metallic structural components and building membranes, and being prepared for future challenges and new developments when these isolative elements are combined with other technologies, as for example, renewable energy harvesting devices.  

Carbon footprint of a reflective foil and comparison with other solutions for thermal insulation in building envelope

International Nuclear Information System (INIS)

Proietti, Stefania; Desideri, Umberto; Sdringola, Paolo; Zepparelli, Francesco

2013-01-01

Highlights: ► Environmental and energy assessment of thermal insulating materials in building envelope. ► Carbon footprint of a reflective foil, conceived and produced by an Italian company. ► Study conducted according to principles of LCA – Life Cycle Assessment. ► Identification of main impacting processes and measures for reducing emissions. ► Comparison with traditional insulating materials (EPS and rockwool). - Abstract: The present study aims at assessing environmental and energy compatibility of different solutions of thermal insulation in building envelope. In fact a good insulation results in a reduction of heating/cooling energy consumptions; on the other hand construction materials undergo production, transformation and transport processes, whose energy and resources consumptions may lead to a significant decrease of the environmental benefits. The paper presents a detailed carbon footprint of a product (CFP, defined as the sum of greenhouse gas emissions and removals of a product system, expressed in CO 2 equivalents), which is a reflective foil conceived and produced by an Italian company. CFP can be seen as a Life Cycle Assessment with climate change as the single impact category; it does not assess other potential social, economic and environmental impacts arising from the provision of products. The analysis considers all stages of the life cycle, from the extraction of raw materials to the product’s disposal, i.e. “from cradle to grave”; it was carried out according to UNI EN ISO 14040 and 14044, and LCA modelling was performed using SimaPro software tool. On the basis of obtained results, different measures have been proposed in order to reduce emissions in the life cycle and neutralize residual carbon footprint. The results allowed to make an important comparison concerning the environmental performance of the reflective foil in comparison with other types of insulating materials

Energy Optimized Envelope for Cold Climate Indoor Agricultural Growing Center

Directory of Open Access Journals (Sweden)

Caroline Hachem-Vermette

2017-07-01

Full Text Available This paper presents a study of the development of building envelope design for improved energy performance of a controlled indoor agricultural growing center in a cold climate zone (Canada, 54° N. A parametric study is applied to analyze the effects of envelope parameters on the building energy loads for heating, cooling and lighting, required for maintaining growing requirement as obtained in the literature. A base case building of rectangular layout, incorporating conventionally applied insulation and glazing components, is initially analyzed, employing the EnergyPlus simulation program. Insulation and glazing parameters are then modified to minimize energy loads under assumed minimal lighting requirement. This enhanced design forms a base case for analyzing effects of additional design parameters—solar radiation control, air infiltration rate, sky-lighting and the addition of phase change materials—to obtain an enhanced design that minimizes energy loads. A second stage of the investigation applies a high lighting level to the enhanced design and modifies the design parameters to improve performance. A final part of the study is an investigation of the mechanical systems and renewable energy generation. Through the enhancement of building envelope components and day-lighting design, combined heating and cooling load of the low level lighting configuration is reduced by 65% and lighting load by 10%, relative to the base case design. Employing building integrated PV (BIPV system, this optimized model can achieve energy positive status. Solid Oxide Fuel Cells (SOFC, are discussed, as potential means to offset increased energy consumption associated with the high-level lighting model.

Performance Evaluation of Modern Building Thermal Envelope Designs in the Semi-Arid Continental Climate of Tehran

Directory of Open Access Journals (Sweden)

Shaghayegh Mohammad

2013-10-01

Full Text Available In this paper we evaluate the thermal performance of a range of modern wall constructions used in the residential buildings of Tehran in order to find the most appropriate alternative to the traditional un-fired clay and brick materials, which are increasingly being replaced in favor of more slender wall constructions employing hollow clay, autoclaved aerated concrete or light expanded clay aggregate blocks. The importance of improving the building envelope through estimating the potential for energy saving due to the application of the most energy-efficient wall type is presented and the wall constructions currently erected in Tehran are introduced along with their dynamic and steady-state thermal properties. The application of a dynamic simulation tool is explained and the output of the thermal simulation model is compared with the dynamic thermal properties of the wall constructions to assess their performance in summer and in winter. Finally, the best and worst wall type in terms of their cyclic thermal performance and their ability to moderate outdoor conditions is identified through comparison of the predicted indoor temperature and a target comfort temperature.

Building thermography as a tool in energy audits and building commissioning procedure

Science.gov (United States)

Kauppinen, Timo

2007-04-01

A Building Commissioning-project (ToVa) was launched in Finland in the year 2003. A comprehensive commissioning procedure, including the building process and operation stage was developed in the project. This procedure will confirm the precise documentation of client's goals, definition of planning goals and the performance of the building. It is rather usual, that within 1-2 years after introduction the users complain about the defects or performance malfunctions of the building. Thermography is one important manual tool in verifying the thermal performance of the building envelope. In this paper the results of one pilot building (a school) will be presented. In surveying the condition and energy efficiency of buildings, various auxiliary means are needed. We can compare the consumption data of the target building with other, same type of buildings by benchmarking. Energy audit helps to localize and determine the energy saving potential. The most general and also most effective auxiliary means in monitoring the thermal performance of building envelopes is an infrared camera. In this presentation some examples of the use of thermography in energy audits are presented.

Advanced Envelope Research for Factory Built Housing, Phase 3 -- Whole-House Prototyping

Energy Technology Data Exchange (ETDEWEB)

Levy, E.; Mullens, M.; Rath, P.

2014-04-01

The Advanced Envelope Research effort will provide factory homebuilders with high performance, cost-effective envelope designs that can be effectively integrated into the plant production process while meeting the thermal requirements of the 2012 IECC standards. Given the affordable nature of manufactured homes, impact on first cost is a major consideration in developing new envelope technologies. This work is part of a multi-phase effort. Phase 1 identified seven envelope technologies and provided a preliminary assessment of three methods for building high performance walls. Phase 2 focused on developing viable product designs, manufacturing strategies, addressing code and structural issues, and cost analysis of the three selected options. An industry advisory committee helped narrow the research focus to perfecting a stud wall design with exterior continuous insulation (CI). Phase 3, completed in two stages, continued the design development effort, exploring and evaluating a range or methods for applying CI to factory built homes. The scope also included material selection, manufacturing and cost analysis, and prototyping and testing. During this phase, a home was built with CI, evaluated, and placed in service. The experience of building a mock up wall section with CI and then constructing on line a prototype home resolved important concerns about how to integrate the material into the production process. First steps were taken toward finding least expensive approaches for incorporating CI in standard factory building practices and a preliminary assessment suggested that even at this early stage the technology is attractive when viewed from a life cycle cost perspective.

Technical support document for proposed 1994 revision of the MEC thermal envelope requirements

Energy Technology Data Exchange (ETDEWEB)

Conner, C.C.; Lucas, R.G.

1994-03-01

This report documents the development of the proposed revision of the Council of American Building Officials` (CABO) 1994 supplement to the 1993 Model Energy Code (MEC) building thermal envelope requirements for maximum component U{sub 0}-value. The 1994 amendments to the 1993 MEC were established in last year`s code change cycle and did not change the envelope requirements. The research underlying the proposed MEC revision was conducted by Pacific Northwest Laboratory (PNL) for the US Department of Energy (DOE) Building Energy Standards program. The goal of this research was to develop revised guidelines based on an objective methodology that determines the most cost-effective (least total cost) combination of energy conservation measures (ECMs) (insulation levels and window types) for residential buildings. This least-cost set of ECMs was used as a basis for proposing revised MEC maximum U{sub 0}-values (thermal transmittances). ECMs include window types (for example, double-pane vinyl) and insulation levels (for example, R-19) for ceilings, walls, and floors.

Danish building typologies

DEFF Research Database (Denmark)

Wittchen, Kim Bjarne; Kragh, Jesper

The objective of TABULA is to develop a harmonised building typology for European countries. Each national building typology will consist of a set of residential model buildings with characteristic energy-related properties (element areas of the thermal building envelope, U-values, supply system...... efficiencies). The model buildings will each represent a specific construction period of the country in question and a specific building size. Furthermore the number of buildings, flats and the overall floor areas will be given, which are represented by the different building types of the national typologies....

Evaluation of Various Retrofitting Concepts of Building Envelope for Offices Equipped with Large Radiant Ceiling Panels by Dynamic Simulations

Directory of Open Access Journals (Sweden)

Sabina Jordan

2015-09-01

Full Text Available In order to achieve significant savings in energy and an improved level of thermal comfort in retrofitted existing buildings, specific retrofitting concepts that combine new technologies and design need to be developed and implemented. Large radiant surfaces systems are now among the most promising future technologies to be used both in retrofitted and in new low-energy buildings. These kinds of systems have been the topic of several studies dealing with thermal comfort and energy utilization, but some specific issues concerning their possible use in various concepts for retrofitting are still poorly understood. In the present paper, some results of dynamic simulations, with the transient system simulation tool (TRNSYS model, of the retrofitted offices equipped with radiant ceiling panels are presented and thoroughly analysed. Based on a precise comparison of the results of these simulations with actual measurements in the offices, certain input data for the model were added, so that the model was consequently validated. The model was then applied to the evaluation of various concepts of building envelopes for office retrofitting. By means of dynamic simulations of indoor environment it was possible to determine the benefits and limitations of individual retrofitting concepts. Some specific parameters, which are relevant to these concepts, were also identified.

Performance Based Envelopes: A Theory of Spatialized Skins and the Emergence of the Integrated Design Professional

Directory of Open Access Journals (Sweden)

Franca Trubiano

2013-10-01

Full Text Available Realigning the design of building envelopes within the measures of air, light and heat has rendered possible an inventive form of practice whose benefits are far in excess of the metrics of data and analysis. For many of its most advanced practitioners, the contemporary design of facades engages the true potential of “performance” when it deepens, broadens and complicates the theoretical dimension of this most liminal of surfaces. Of particular interest to this paper is a discussion of new theoretical paradigms associated with the design and operation of high performance envelopes of which four characteristics of this emergent sub-discipline are herein examined. To begin with, the way in which building envelopes are no longer separators, dividers and barriers between a building’s interior and exterior conditions, but rather, “spatially” defined environments that fully engage the totality of a building’s engineering systems, is discussed. Cantilevered Louvers, Double Skin Facades and Hybrid Conditioned Atria are representative of this new paradigm as is the use of Responsive Technologies to optimize their behaviors. Lastly, the paper examines the rise of the new integrated design building envelope professional called upon to deliver ever-better performing skins, whether in the guise of energy modeler, climate engineer or façade construction specialist. Hence, this paper develops a theoretical structure within which to describe, analyze and interpret the values made possible by this new and expanding field of performance based envelopes.

Tank waste remediation system (TWRS) privatization contractor samples waste envelope D material 241-C-106

Energy Technology Data Exchange (ETDEWEB)

Esch, R.A.

1997-04-14

This report represents the Final Analytical Report on Tank Waste Remediation System (TWRS) Privatization Contractor Samples for Waste Envelope D. All work was conducted in accordance with ''Addendum 1 of the Letter of Instruction (LOI) for TWRS Privatization Contractor Samples Addressing Waste Envelope D Materials - Revision 0, Revision 1, and Revision 2.'' (Jones 1996, Wiemers 1996a, Wiemers 1996b) Tank 241-C-1 06 (C-106) was selected by TWRS Privatization for the Part 1A Envelope D high-level waste demonstration. Twenty bottles of Tank C-106 material were collected by Westinghouse Hanford Company using a grab sampling technique and transferred to the 325 building for processing by the Pacific Northwest National Laboratory (PNNL). At the 325 building, the contents of the twenty bottles were combined into a single Initial Composite Material. This composite was subsampled for the laboratory-scale screening test and characterization testing, and the remainder was transferred to the 324 building for bench-scale preparation of the Privatization Contractor samples.

Occupant behaviour and robustness of building design

DEFF Research Database (Denmark)

Buso, Tiziana; Fabi, Valentina; Andersen, Rune Korsholm

2015-01-01

in a dynamic building energy simulation tool (IDA ICE). The analysis was carried out by simulating 15 building envelope designs in different thermal zones of an Office Reference Building in 3 climates: Stockholm, Frankfurt and Athens.In general, robustness towards changes in occupants' behaviour increased......Occupant behaviour can cause major discrepancies between the designed and the real total energy use in buildings. A possible solution to reduce the differences between predictions and actual performances is designing robust buildings, i.e. buildings whose performances show little variations...... with alternating occupant behaviour patterns. The aim of this work was to investigate how alternating occupant behaviour patterns impact the performance of different envelope design solutions in terms of building robustness. Probabilistic models of occupants' window opening and use of shading were implemented...

Energy performance requirements for new buildings in 11 countries from Central Europe. Exemplary comparison of three buildings

Energy Technology Data Exchange (ETDEWEB)

Loga, Tobias; Knissel, Jens; Diefenbach, Nikolaus

2008-12-05

The objective of the present comparison study is to show which energy efficiency require-ments have to be complied in different European countries when a new building is going to be constructed. For this purpose three Model Buildings were defined: a single-family house, a multi-family house and a school building. For each involved country (or region) the energy quality of the thermal envelope was determined which is necessary in order to just comply with the building code. Due to requirements on the overall energy performance the requested envelope quality usually depends also on the type of heat supply system or energy carrier. Therefore the systems were varied in a parameter study. The main result for each of the three Model Buildings is a comparison table which shows the heat transfer coefficient by transmission (a sort of mean U-value) for the different countries differenti-ated by supply system types. In a final step the primary energy demand according to the German regulation (EnEV 2007) was calculated for every envelope/system combination of the different countries. This allows a comparison of buildings with different supply systems. The study was performed by experts from 11 European member states: Germany, Austria, Czech Republic, Poland, Sweden, Denmark, UK, The Netherlands, Belgium, Luxembourg and France. (orig.)

Greenbelt Homes Pilot Program: Summary of Building Envelope Retrofits, Planned HVAC Equipment Upgrades, and Energy Savings

Energy Technology Data Exchange (ETDEWEB)

Wiehagen, J. [Partnership for Home Innovation, Upper Marlboro, MD (United States); Del Bianco, M. [Partnership for Home Innovation, Upper Marlboro, MD (United States); Mallay, D. [Partnership for Home Innovation, Upper Marlboro, MD (United States)

2015-05-01

In the fall of 2010, a multiyear pilot energy efficiency retrofit project was undertaken by Greenbelt Homes, Inc, (GHI) a 1,566 home cooperative of circa 1930 and 1940 homes in Greenbelt, Maryland. GHI established this pilot project to serve as a basis for decision making for the rollout of a decade-long community-wide upgrade program that will incorporate energy efficiency improvements to the building envelope and mechanical equipment. It presents a unique opportunity to evaluate and prioritize the wide-range of benefits of high-performance retrofits based on member experience with and acceptance of the retrofit measures implemented during the pilot project. Addressing the complex interactions between benefits, trade-offs, construction methods, project management implications, realistic upfront costs, financing, and other considerations, serves as a case study for energy retrofit projects to include high-performance technologies based on the long-term value to the homeowner. The pilot project focused on identifying the added costs and energy savings benefits of improvements.

Envelope colour on thermal load in hot humid Hong Kong： Effect of hue, value, and chroma

Institute of Scientific and Technical Information of China (English)

VickyCHENG; EdwardNG

2003-01-01

Cooling energy consumption of a building can be significantly reduced by limiting solar heat gain through envelope, in which depends on the intensity of impinging solar radiation and on the colour of external surface. Albedo, from the thermal point of view, is the prime parameter of interest; however, it does appear to be too conceptual in practice. Architects, when considering choices of envelope colour, the actual decision is between various colours: yellow, blue, or green rather than a single numerical albedo. This study is to investigate the effect and magnitude of colour, in terms of visual qualities hue, value (lightness), and chroma (saturation), on thermal load of buildings. In the experiment, air temperatures inside test cells painted into different colours were measured, the results suggest that colour attribute: chroma has negligible effect on thermal performance of building envelope, while value has significant thermal effect. The effect of hue, as shown in this study, was insignificant, however further study might be needed as to obtain a clearer picture of its effect.

Super-structure and building performance

CSIR Research Space (South Africa)

Van Wyk, Llewellyn V

2010-11-01

Full Text Available The super-structure consists predominantly of the load- and no-load-bearing walls-including all doors and windows and suspended floor slabs. The building envelope plays a significant role in the performance of a building, especially with regard...

Development of Building Envelope Constructions

DEFF Research Database (Denmark)

Tommerup, Henrik Monefeldt; Munch-Andersen, Jørgen; Esbensen, Peter Kjær

2000-01-01

It is expected that the heat insulation demands in the Danish Building Regulations will be further increased around 2005, in order to reduce the heating demand and the CO2-emission. A simple increase of the insulation thickness of common wall types seems not to be attractive due to the increased...... effect of the 2-dimensional heat loss, the large wall thickness, and the costs of the wide foundation. Therefore, new types of walls have been developed. It is sought to minimise the total heat loss as well as the material consumption. The target was to come up with new walls for which the construction...

Active materials for adaptive architectural envelopes based on plant adaptation principles

Directory of Open Access Journals (Sweden)

Marlen Lopez

2015-06-01

Full Text Available In this paper, the authors present research into adaptive architectural envelopes that adapt to environmental changes using active materials, as a result of application of biomimetic principles from plants to architecture. Buildings use large amounts of energy in order to maintain their internal comfort, because conventional buildings are designed to provide a static design solution. Most of the current solutions for facades are not designed for optimum adaptation to contextual issues and needs, while biological solutions to adaptation are often complex, multi-functional and highly responsive. We focus on plant adaptations to the environment, as, due to their immobility, they have developed special means of protection against weather changing conditions. Furthermore, recent developments in new technologies are allowing the possibility to transfer these plant adaptation strategies to technical implementation. These technologies include: multi-material 3D printing, advances in materials science and new capabilities in simulation software. Unlike traditional mechanical activation used for dynamic systems in kinetic facades, adaptive architectural envelopes require no complex electronics, sensors, or actuators. The paper proposes a research of the relationship that can be developed between active materials and environmental issues in order to propose innovative and low-tech design strategies to achieve living envelopes according to plant adaptation principles.  

Advanced Envelope Research for Factory Built Housing, Phase 3. Whole-House Prototyping

Energy Technology Data Exchange (ETDEWEB)

Levy, E. [Advanced Residential Integrated Energy Solutions (ARIES), New York, NY (United States); Mullens, M. [Advanced Residential Integrated Energy Solutions (ARIES), New York, NY (United States); Rath, P. [Advanced Residential Integrated Energy Solutions (ARIES), New York, NY (United States)

2014-04-01

The Advanced Envelope Research effort will provide factory homebuilders with high performance, cost-effective envelope designs that can be effectively integrated into the plant production process while meeting the thermal requirements of the 2012 IECC standards. This work is part of a multiphase effort. Phase 1 identified seven envelope technologies and provided a preliminary assessment of three methods for building high performance walls. Phase 2 focused on developing viable product designs, manufacturing strategies, addressing code and structural issues, and cost analysis of the three selected options. An industry advisory committee helped narrow the research focus to perfecting a stud wall design with exterior continuous insulation (CI). This report describes Phase 3, which was completed in two stages and continued the design development effort, exploring and evaluating a range or methods for applying CI to factory built homes. The scope also included material selection, manufacturing and cost analysis, and prototyping and testing. During this phase, a home was built with CI, evaluated, and placed in service. The experience of building a mock up wall section with CI and then constructing on line a prototype home resolved important concerns about how to integrate the material into the production process. First steps were taken toward finding least expensive approaches for incorporating CI in standard factory building practices and a preliminary assessment suggested that even at this early stage the technology is attractive when viewed from a life cycle cost perspective.

Impact of coupled heat and moisture transfer effects on buildings energy consuption

Directory of Open Access Journals (Sweden)

Ferroukhi Mohammed Yacine

2017-01-01

Full Text Available Coupled heat, air, and moisture transfers through building envelope have an important effect on prediction of building energy requirements. Several works were conducted in order to integrate hygrothermal transfers in dynamic buildings simulations codes. However, the incorporation of multidirectional hygrothermal transfer analysis in the envelope into building simulation tools is rarely considered. In this work, coupled heat, air, and moisture (HAM transfer model in multilayer walls was established. Thereafter, the HAM model is coupled dynamically to a building behavior code (BES.The coupling concerns a co-simulation between COMSOL Multiphysics and TRNSYS software. Afterward, the HAM-BES co-simulation accuracy was verified. Then, HAM-BES co-simulation platform was applied to a case study with various types of climates (temperate, hot and humid, cold and humid. Three simulations cases were carried out. The first simulation case consists of the TRNSYS model without HAM transfer model. The second simulation case, 1-D HAM model for the envelope was integrated in TRNSYS code. For the third one, 1-D HAM model for the wall and 2-D HAM model for thermal bridges were coupled to the thermal building model of TRNSYS. Analysis of the results confirms the significant impact of 2-D envelope hygrothermal transfers on the indoor thermal and moisture behavior of building as well as on the energy building assessment. These conclusions are shown for different studied climates.

Multi-Objective Optimal Design of a Building Envelope and Structural System Using Cyber-Physical Modeling in a Wind Tunnel

Directory of Open Access Journals (Sweden)

Michael L. Whiteman

2018-03-01

Full Text Available This paper explores the use of a cyber-physical systems (CPS “loop-in-the-model” approach to optimally design the envelope and structural system of low-rise buildings subject to wind loads. Both the components and cladding (C&C and the main wind force resisting system (MWFRS are considered through multi-objective optimization. The CPS approach combines the physical accuracy of wind tunnel testing and efficiency of numerical optimization algorithms to obtain an optimal design. The approach is autonomous: experiments are executed in a boundary layer wind tunnel (BLWT, sensor feedback is monitored and analyzed by a computer, and optimization algorithms dictate physical changes to the structural model in the BLWT through actuators. To explore a CPS approach to multi-objective optimization, a low-rise building with a parapet wall of variable height is considered. In the BLWT, servo-motors are used to adjust the parapet to a particular height. Parapet walls alter the location of the roof corner vortices, reducing suction loads on the windward facing roof corners and edges, a C&C design load. At the same time, parapet walls increase the surface area of the building, leading to an increase in demand on the MWFRS. A combination of non-stochastic and stochastic optimization algorithms were implemented to minimize the magnitude of suction and positive pressures on the roof of a low-rise building model, followed by stochastic multi-objective optimization to simultaneously minimize the magnitude of suction pressures and base shear. Experiments were conducted at the University of Florida Experimental Facility (UFEF of the National Science Foundation’s (NSF Natural Hazard Engineering Research Infrastructure (NHERI program.

Enveloping Aerodynamic Decelerator

Science.gov (United States)

Nock, Kerry T. (Inventor); Aaron, Kim M. (Inventor); McRonald, Angus D. (Inventor); Gates, Kristin L. (Inventor)

2018-01-01

An inflatable aerodynamic deceleration method and system is provided for use with an atmospheric entry payload. The inflatable aerodynamic decelerator includes an inflatable envelope and an inflatant, wherein the inflatant is configured to fill the inflatable envelope to an inflated state such that the inflatable envelope surrounds the atmospheric entry payload, causing aerodynamic forces to decelerate the atmospheric entry payload.

Benchmarking energy performance of residential buildings using two-stage multifactor data envelopment analysis with degree-day based simple-normalization approach

International Nuclear Information System (INIS)

Wang, Endong; Shen, Zhigang; Alp, Neslihan; Barry, Nate

2015-01-01

Highlights: • Two-stage DEA model is developed to benchmark building energy efficiency. • Degree-day based simple normalization is used to neutralize the climatic noise. • Results of a real case study validated the benefits of this new model. - Abstract: Being able to identify detailed meta factors of energy performance is essential for creating effective residential energy-retrofitting strategies. Compared to other benchmarking methods, nonparametric multifactor DEA (data envelopment analysis) is capable of discriminating scale factors from management factors to reveal more details to better guide retrofitting practices. A two-stage DEA energy benchmarking method is proposed in this paper. This method includes (1) first-stage meta DEA which integrates the common degree day metrics for neutralizing noise energy effects of exogenous climatic variables; and (2) second-stage Tobit regression for further detailed efficiency analysis. A case study involving 3-year longitudinal panel data of 189 residential buildings indicated the proposed method has advantages over existing methods in terms of its efficiency in data processing and results interpretation. The results of the case study also demonstrated high consistency with existing linear regression based DEA.

(Quasi-)Poisson enveloping algebras

OpenAIRE

Yang, Yan-Hong; Yao, Yuan; Ye, Yu

2010-01-01

We introduce the quasi-Poisson enveloping algebra and Poisson enveloping algebra for a non-commutative Poisson algebra. We prove that for a non-commutative Poisson algebra, the category of quasi-Poisson modules is equivalent to the category of left modules over its quasi-Poisson enveloping algebra, and the category of Poisson modules is equivalent to the category of left modules over its Poisson enveloping algebra.

The impact of roofing material on building energy performance

Science.gov (United States)

Badiee, Ali

The last decade has seen an increase in the efficient use of energy sources such as water, electricity, and natural gas as well as a variety of roofing materials, in the heating and cooling of both residential and commercial infrastructure. Oil costs, coal and natural gas prices remain high and unstable. All of these instabilities and increased costs have resulted in higher heating and cooling costs, and engineers are making an effort to keep them under control by using energy efficient building materials. The building envelope (that which separates the indoor and outdoor environments of a building) plays a significant role in the rate of building energy consumption. An appropriate architectural design of a building envelope can considerably lower the energy consumption during hot summers and cold winters, resulting in reduced HVAC loads. Several building components (walls, roofs, fenestration, foundations, thermal insulation, external shading devices, thermal mass, etc.) make up this essential part of a building. However, thermal insulation of a building's rooftop is the most essential part of a building envelope in that it reduces the incoming "heat flux" (defined as the amount of heat transferred per unit area per unit time from or to a surface) (Sadineni et al., 2011). Moreover, more than 60% of heat transfer occurs through the roof regardless of weather, since a roof is often the building surface that receives the largest amount of solar radiation per square annually (Suman, and Srivastava, 2009). Hence, an argument can be made that the emphasis on building energy efficiency has influenced roofing manufacturing more than any other building envelope component. This research project will address roofing energy performance as the source of nearly 60% of the building heat transfer (Suman, and Srivastava, 2009). We will also rank different roofing materials in terms of their energy performance. Other parts of the building envelope such as walls, foundation

Building Performance Simulation tools for planning of energy efficiency retrofits

DEFF Research Database (Denmark)

Mondrup, Thomas Fænø; Karlshøj, Jan; Vestergaard, Flemming

2014-01-01

Designing energy efficiency retrofits for existing buildings will bring environmental, economic, social, and health benefits. However, selecting specific retrofit strategies is complex and requires careful planning. In this study, we describe a methodology for adopting Building Performance...... to energy efficiency retrofits in social housing. To generate energy savings, we focus on optimizing the building envelope. We evaluate alternative building envelope actions using procedural solar radiation and daylight simulations. In addition, we identify the digital information flow and the information...... Simulation (BPS) tools as energy and environmentally conscious decision-making aids. The methodology has been developed to screen buildings for potential improvements and to support the development of retrofit strategies. We present a case study of a Danish renovation project, implementing BPS approaches...

10 CFR 434.516 - Building exterior envelope.

Science.gov (United States)

2010-01-01

... Buildings for calculating the Energy Cost Budget. In calculating the Design Energy Consumption of the... assumptions for calculating the Energy Cost Budget and default assumptions for the Design Energy Consumption... without operable windows shall be assumed to be 0.038 cfm/ft2 of gross exterior wall. Hotels/motels and...

Weather Correlations to Calculate Infiltration Rates for U. S. Commercial Building Energy Models.

Science.gov (United States)

Ng, Lisa C; Quiles, Nelson Ojeda; Dols, W Stuart; Emmerich, Steven J

2018-01-01

As building envelope performance improves, a greater percentage of building energy loss will occur through envelope leakage. Although the energy impacts of infiltration on building energy use can be significant, current energy simulation software have limited ability to accurately account for envelope infiltration and the impacts of improved airtightness. This paper extends previous work by the National Institute of Standards and Technology that developed a set of EnergyPlus inputs for modeling infiltration in several commercial reference buildings using Chicago weather. The current work includes cities in seven additional climate zones and uses the updated versions of the prototype commercial building types developed by the Pacific Northwest National Laboratory for the U. S. Department of Energy. Comparisons were made between the predicted infiltration rates using three representations of the commercial building types: PNNL EnergyPlus models, CONTAM models, and EnergyPlus models using the infiltration inputs developed in this paper. The newly developed infiltration inputs in EnergyPlus yielded average annual increases of 3 % and 8 % in the HVAC electrical and gas use, respectively, over the original infiltration inputs in the PNNL EnergyPlus models. When analyzing the benefits of building envelope airtightening, greater HVAC energy savings were predicted using the newly developed infiltration inputs in EnergyPlus compared with using the original infiltration inputs. These results indicate that the effects of infiltration on HVAC energy use can be significant and that infiltration can and should be better accounted for in whole-building energy models.

Final Technical Report. Training in Building Audit Technologies

Energy Technology Data Exchange (ETDEWEB)

Brosemer, Kathleen [Sault Sainte Marie Tribe of Chippewa Indians, Marie, MI (United States)

2015-03-27

In 2011, the Tribe proposed and was awarded the Training in Building Audit Technologies grant from the DOE in the amount of $55,748 to contract for training programs for infrared cameras, blower door technology applications and building systems. The coursework consisted of; Infrared Camera Training: Level I - Thermal Imaging for Energy Audits; Blower Door Analysis and Building-As-A-System Training, Building Performance Institute (BPI) Building Analyst; Building Envelope Training, Building Performance Institute (BPI) Envelope Professional; and Audit/JobFLEX Tablet Software. Competitive procurement of the training contractor resulted in lower costs, allowing the Tribe to request and receive DOE approval to additionally purchase energy audit equipment and contract for residential energy audits of 25 low-income Tribal Housing units. Sault Tribe personnel received field training to supplement the classroom instruction on proper use of the energy audit equipment. Field experience was provided through the second DOE energy audits grant, allowing Sault Tribe personnel to join the contractor, Building Science Academy, in conducting 25 residential energy audits of low-income Tribal Housing units.

Storage envelopes or sleeves

International Nuclear Information System (INIS)

Freshwater, J.R.; Wagman, P.I.

1980-01-01

A storage envelope or sleeve particularly for processed X-ray films is described. It consists of front and back panels joined together at a hinge line and connected along the intermediate sides by connecting flaps. An inner pocket is formed from a third flap which is folded to lie against the inner face of the back panel. The panels may have additional score lines parallel to the closed sides of the envelope and the inner pocket so that the envelope and the inner pocket can accommodate bulky contents. The free edge of the pocket is inset from the open side of the envelope, and finger cut-outs may be provided to facilitate access to the contents of the envelope and the pocket. (author)

Protective plasma envelope

International Nuclear Information System (INIS)

Bocharov, V.N.; Konstantinov, S.G.; Kudryavtsev, A.M.; Myskin, O.K.; Panasyuk, V.M.; Tsel'nik, F.A.

1984-06-01

A method of creating an annular plasma envelope used to protect the hot plasma from flows of impurities and gases from the walls of the vacuum chamber is described. The diameter of the envelope is 30 cm, the thickness of the wall is 1.5 cm, the length is 2.5 m, and its density is from 10 13 to 10 14 cm -3 . The envelope attenuates the incident (from outside) flow of helium 10-fold and the low of hydrogen 20-fold

Complex analysis of energy efficiency in operated high-rise residential building: Case study

Science.gov (United States)

Korniyenko, Sergey

2018-03-01

Energy conservation and human thermal comfort enhancement in buildings is a topical issue of modern architecture and construction. The innovative solution of this problem makes it possible to enhance building ecological and maintenance safety, to reduce hydrocarbon fuel consumption, and to improve life standard of people. The requirements to increase of energy efficiency in buildings should be provided at all the stages of building's life cycle that is at the stage of design, construction and maintenance of buildings. The research purpose is complex analysis of energy efficiency in operated high-rise residential building. Many actions for building energy efficiency are realized according to the project; mainly it is the effective building envelope and engineering systems. Based on results of measurements the energy indicators of the building during annual period have been calculated. The main reason of increase in heat losses consists in the raised infiltration of external air in the building through a building envelope owing to the increased air permeability of windows and balcony doors (construction defects). Thermorenovation of the building based on ventilating and infiltration heat losses reduction through a building envelope allows reducing annual energy consumption. Energy efficiency assessment based on the total annual energy consumption of building, including energy indices for heating and a ventilation, hot water supply and electricity supply, in comparison with heating is more complete. The account of various components in building energy balance completely corresponds to modern direction of researches on energy conservation and thermal comfort enhancement in buildings.

Chaetomium and Stachybotrys in water-damaged buildings

DEFF Research Database (Denmark)

Andersen, Birgitte; Lewinska, Anna Malgorzata; Nielsen, Jakob Blæsbjerg

Fungal growth occurs when parts of the building envelope get very wet due to unfortunate combinations of factors, e.g. thermal bridges/lack of ventilation, shoddy foundations/flooding or leaks in build-in pipes. Chaetomium and Stachybotrys are not as abundant as Penicillium and Aspergillus (Table 1...

Energy Code Compliance in a Detailed Commercial Building Sample: The Effects of Missing Data

Energy Technology Data Exchange (ETDEWEB)

Biyani, Rahul K.; Richman, Eric E.

2003-09-30

Most commercial buildings in the U.S. are required by State or local jurisdiction to meet energy standards. The enforcement of these standards is not well known and building practice without them on a national scale is also little understood. To provide an understanding of these issues, a database has been developed at PNNL that includes detailed energy related building characteristics of 162 commercial buildings from across the country. For this analysis, the COMcheck? compliance software (developed at PNNL) was used to assess compliance with energy codes among these buildings. Data from the database for each building provided the program input with percentage energy compliance to the ASHRAE/IESNA Standard 90.1-1999 energy as the output. During the data input process it was discovered that some essential data for showing compliance of the building envelope was missed and defaults had to be developed to provide complete compliance information. This need for defaults for some data inputs raised the question of what the effect on documenting compliance could be due to missing data. To help answer this question a data collection effort was completed to assess potential differences. Using the program Dodge View, as much of the missing envelope data as possible was collected from the building plans and the database input was again run through COMcheck?. The outputs of both compliance runs were compared to see if the missing data would have adversely affected the results. Both of these results provided a percentage compliance of each building in the envelope and lighting categories, showing by how large a percentage each building either met or fell short of the ASHRAE/IESNA Standard 90.1-1999 energy code. The results of the compliance runs showed that 57.7 % of the buildings met or exceeded envelope requirements with defaults and that 68 % met or exceeded envelope requirements with the actual data. Also, 53.6 % of the buildings met or surpassed the lighting requirements

DEA (data envelopment analysis)-assisted supporting measures for ground coupled heat pumps implementing in Italy: A case study

International Nuclear Information System (INIS)

Longo, L.; Colantoni, A.; Castellucci, S.; Carlini, M.; Vecchione, L.; Savuto, E.; Pallozzi, V.; Di Carlo, A.; Bocci, E.; Moneti, M.; Cocchi, S.; Boubaker, K.

2015-01-01

Nowadays, the increasing of the energy consumption is producing serious global warming issues. Mainly most of greenhouse gas emissions in developed countries come from building equipments. In this context, GCHPs (ground coupled heat pumps) are candidate solution as air conditioning systems in buildings due to their higher efficiency compared to conventional devices. Actually, ground coupled heat pump systems are widely, recognized among the most efficient and comfortable used systems. Nevertheless, economic efficiency of the ground coupled heat pumps has to be proved. In this study, DEA (data envelopment analyses) method is applied to a real case in Italy. - Highlights: • Original investigation in terms of energy demands in buildings. • Gathering conjoint classical and scientific analyses. • Presenting original DEA (data envelopment analysis) economic optimization scheme analyses. • Outlining economical feasibility of an efficient low enthalpy-geothermal plant with GCHP (ground coupled heat pump) exchangers.

Evaluating solar irradiance over facades in high building cities, based on LiDAR technology

International Nuclear Information System (INIS)

Martínez-Rubio, A.; Sanz-Adan, F.; Santamaría-Peña, J.; Martínez, Araceli

2016-01-01

Highlights: • A method for evaluating solar irradiance over façades in building cities with mutual shading. • It calculates irradiance curves in all building façades, using LiDAR and irradiance information. • Solar irradiation maps of the city buildings are really important for urban planning. • It allows to selection BIPV elements depending of the irradiation in each façade point. • The model can be extrapolated to all the building envelope. - Abstract: Arranging a solar irradiation map of the buildings of a city is a valuable tool for sustainable urban planning in regard to non-carbonized criteria in important applications. Such applications may include: selection of materials for the building envelope and insulation according to the irradiation received at each point; monitoring the installation of photovoltaic systems to ensure that they are located in the optimal irradiance zones; or building restoration to improve the energy efficiency and electric generation. The proposed method enables to estimate the incidence of the solar irradiance as well as to visualize the effect it produces in every region of the buildings that compose the urban area of a city. The process includes the use of Laser Imaging Detection and Ranging (LiDAR) information along with 5-min horizontal irradiance data. This developed algorithm has been verified through being applied to different building envelopes distributed in different geographical areas. The results demonstrate a satisfied performance which makes that the methodology can be extrapolated to any city where the LiDAR Data and irradiance information are available, permitting an accurate analysis of the solar irradiance over the building envelopes. The algorithm succeeds in obtaining a map of solar radiation captured by the envelope of any urban building that estimates the photovoltaic power generation depending on the geographic location and on the influence of shading caused by adjacent buildings. The provided

Flood vulnerability assessment of residential buildings by explicit damage process modelling

DEFF Research Database (Denmark)

Custer, Rocco; Nishijima, Kazuyoshi

2015-01-01

The present paper introduces a vulnerability modelling approach for residential buildings in flood. The modelling approach explicitly considers relevant damage processes, i.e. water infiltration into the building, mechanical failure of components in the building envelope and damage from water...

Complex analysis of energy efficiency in operated high-rise residential building: Case study

Directory of Open Access Journals (Sweden)

Korniyenko Sergey

2018-01-01

Full Text Available Energy conservation and human thermal comfort enhancement in buildings is a topical issue of modern architecture and construction. The innovative solution of this problem makes it possible to enhance building ecological and maintenance safety, to reduce hydrocarbon fuel consumption, and to improve life standard of people. The requirements to increase of energy efficiency in buildings should be provided at all the stages of building's life cycle that is at the stage of design, construction and maintenance of buildings. The research purpose is complex analysis of energy efficiency in operated high-rise residential building. Many actions for building energy efficiency are realized according to the project; mainly it is the effective building envelope and engineering systems. Based on results of measurements the energy indicators of the building during annual period have been calculated. The main reason of increase in heat losses consists in the raised infiltration of external air in the building through a building envelope owing to the increased air permeability of windows and balcony doors (construction defects. Thermorenovation of the building based on ventilating and infiltration heat losses reduction through a building envelope allows reducing annual energy consumption. Energy efficiency assessment based on the total annual energy consumption of building, including energy indices for heating and a ventilation, hot water supply and electricity supply, in comparison with heating is more complete. The account of various components in building energy balance completely corresponds to modern direction of researches on energy conservation and thermal comfort enhancement in buildings.

Economical optimization of building elements for use in design of nearly zero energy buildings

DEFF Research Database (Denmark)

Hansen, Sanne

2012-01-01

Nearly zero energy buildings are to become a requirement as part of the European energy policy. There are many ways of designing nearly zero energy buildings, but there is a lack of knowledge on how to end up with the most economical optimal solution. Therefore this paper present a method...... for finding the economical optimal solutions based on the use of the cost of conserved energy for each main building envelope part and building service system and cost of produced energy for each energy producing system. By use of information on construction cost and developed models of the yearly energy use...

An Assessment of Envelope Measures in Mild Climate Deep Energy Retrofits

Energy Technology Data Exchange (ETDEWEB)

Walker, Iain [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Less, Brennan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2014-06-01

Energy end-uses and interior comfort conditions have been monitored in 11 Deep Energy Retrofits (DERs) in a mild marine climate. Two broad categories of DER envelope were identified: first, bringing homes up to current code levels of insulation and airtightness, and second, enhanced retrofits that go beyond these code requirements. The efficacy of envelope measures in DERs was difficult to determine, due to the intermingled effects of enclosure improvements, HVAC system upgrades and changes in interior comfort conditions. While energy reductions in these project homes could not be assigned to specific improvements, the combined effects of changes in enclosure, HVAC system and comfort led to average heating energy reductions of 76percent (12,937 kWh) in the five DERs with pre-retrofit data, or 80percent (5.9 kWh/ft2) when normalized by floor area. Overall, net-site energy reductions averaged 58percent (15,966 kWh; n=5), and DERs with code-style envelopes achieved average net-site energy reductions of 65percent (18,923 kWh; n=4). In some homes, the heating energy reductions were actually larger than the whole house reductions that were achieved, which suggests that substantial additional energy uses were added to the home during the retrofit that offset some heating savings. Heating system operation and energy use was shown to vary inconsistently with outdoor conditions, suggesting that most DERs were not thermostatically controlled and that occupants were engaged in managing the indoor environmental conditions. Indoor temperatures maintained in these DERs were highly variable, and no project home consistently provided conditions within the ASHRAE Standard 55-2010 heating season comfort zone. Thermal comfort and heating system operation had a large impact on performance and were found to depend upon the occupant activities, so DERs should be designed with the occupants needs and patterns of consumption in mind. Beyond-code building envelopes were not found to be

Office Building, Roskilde, Denmark. Parkvænget 25, 4000 Roskilde

DEFF Research Database (Denmark)

Rose, Jørgen; Thomsen, Kirsten Engelund

Built in 1968 the office building was a typical precast concrete building with a very limited level of insulation. In 1991 the building envelope was renovated and insulation was added to the wall (175 mm) and windows were replaced with traditional double-glazed windows. The main objective...

The LHC on an envelope

CERN Multimedia

2007-01-01

The series of envelopes featuring CERN issued this summer was a huge success. The French postal services of the Pays de Gex will shortly be launching the second set of pre-paid envelopes issued in collaboration with the Laboratory this year, this time highlighting the LHC. Five thousand envelopes describing the accelerator’s capabilities will go on sale on 12 November, and some of the packs will even contain a small sample of the cables from the heart of the LHC magnets. The sets of ten pre-paid envelopes will tell you everything about CERN’s flagship accelerator, from its astounding technical capabilities to its spin-offs in the fields of technology and human resources. Each envelope will feature a different attribute or spin-off of the LHC. People will be invited to consult CERN’s public website for more detailed explanations if they want to know more. The new envelopes will be available from five post offices in the Pays ...

Climate control in cultural heritage buildings in Denmark

Energy Technology Data Exchange (ETDEWEB)

Larsen, Poul Klenz [The National Museum, Copenhagen (Denmark). Dept. of Conservation; Brostroem, Tor [Gotland Univ., Visby (Sweden)

2011-07-01

Conservation heating has been used for decades to control the RH in cultural heritage buildings. But if the building is not used for living or working, heating is not needed for human comfort. The chemical decay of organic materials depends mainly on temperature, so it is better for preservation to reduce heating. The air exchange rate is related to the design of the building envelope. With rising energy prices humidity control by dehumidification may be an attractive alternative. The potential for energy efficient RH control was examined for a generic building exposed to the monthly average outside temperature and RH in Denmark. The indoor temperature was allowed to follow the outside average, whereas the indoor RH was controlled to 40 % 50 % 60 % or 70 %. Dehumidification was implemented in three different buildings: A recent museum store, a medieval church, and an 18th century country mansion. The energy consumption depends on the RH set point, the air exchange rate and the source of liquid moisture to the building. The air exchange rate related to the design of the building envelope. Single glazed windows and doors are the most important sources of leakage to buildings. Lack of maintenance may lead to poor performance of the dehumidifier and waste energy. (orig.)

The LHC in an envelope

CERN Multimedia

2007-01-01

The series of envelopes featuring CERN issued this summer was a huge success. The French postal services of the Pays de Gex will shortly be launching the second set of pre-paid envelopes issued in collaboration with the Laboratory this year, this time highlighting the LHC. Five thousand envelopes describing the accelerator’s capabilities will go on sale on 12 November, and some of the packs will even contain a small sample of the cables from the heart of the LHC magnets. The sets of ten pre-paid envelopes will tell you everything about CERN’s flagship accelerator, from its astounding technical capabilities to its spin-offs in the fields of technology and human resources. Each envelope will feature a different attribute or spin-off of the LHC. People will be invited to consult CERN’s public website for more detailed explanations if they want to know more. The new envelopes will be available from five post offices in the Pays de Gex (Ferney-Voltaire, Prévessin...

Intelligent Facades for High Performance Green Buildings

Energy Technology Data Exchange (ETDEWEB)

Dyson, Anna [Rensselaer Polytechnic Inst., Troy, NY (United States)

2017-03-01

Progress Towards Net-Zero and Net-Positive-Energy Commercial Buildings and Urban Districts Through Intelligent Building Envelope Strategies Previous research and development of intelligent facades systems has been limited in their contribution towards national goals for achieving on-site net zero buildings, because this R&D has failed to couple the many qualitative requirements of building envelopes such as the provision of daylighting, access to exterior views, satisfying aesthetic and cultural characteristics, with the quantitative metrics of energy harvesting, storage and redistribution. To achieve energy self-sufficiency from on-site solar resources, building envelopes can and must address this gamut of concerns simultaneously. With this project, we have undertaken a high-performance building integrated combined-heat and power concentrating photovoltaic system with high temperature thermal capture, storage and transport towards multiple applications (BICPV/T). The critical contribution we are offering with the Integrated Concentrating Solar Façade (ICSF) is conceived to improve daylighting quality for improved health of occupants and mitigate solar heat gain while maximally capturing and transferring onsite solar energy. The ICSF accomplishes this multi-functionality by intercepting only the direct-normal component of solar energy (which is responsible for elevated cooling loads) thereby transforming a previously problematic source of energy into a high quality resource that can be applied to building demands such as heating, cooling, dehumidification, domestic hot water, and possible further augmentation of electrical generation through organic Rankine cycles. With the ICSF technology, our team is addressing the global challenge in transitioning commercial and residential building stock towards on-site clean energy self-sufficiency, by fully integrating innovative environmental control systems strategies within an intelligent and responsively dynamic building

Country Report on Building Energy Codes in China

Energy Technology Data Exchange (ETDEWEB)

Shui, Bin; Evans, Meredydd; Lin, H.; Jiang, Wei; Liu, Bing; Song, Bo; Somasundaram, Sriram

2009-04-15

This report is part of a series of reports on building energy efficiency codes in countries associated with the Asian Pacific Partnership (APP) - Australia, South Korea, Japan, China, India, and the United States of America (U.S.). This reports gives an overview of the development of building energy codes in China, including national energy policies related to building energy codes, history of building energy codes, recent national projects and activities to promote building energy codes. The report also provides a review of current building energy codes (such as building envelope and HVAC) for commercial and residential buildings in China.

Country Report on Building Energy Codes in Japan

Energy Technology Data Exchange (ETDEWEB)

Evans, Meredydd; Shui, Bin; Takagi, T.

2009-04-15

This report is part of a series of reports on building energy efficiency codes in countries associated with the Asian Pacific Partnership (APP) - Australia, South Korea, Japan, China, India, and the United States of America (U.S.). This reports gives an overview of the development of building energy codes in Japan, including national energy policies related to building energy codes, history of building energy codes, recent national projects and activities to promote building energy codes. The report also provides a review of current building energy codes (such as building envelope, HVAC, and lighting) for commercial and residential buildings in Japan.

Country Report on Building Energy Codes in Australia

Energy Technology Data Exchange (ETDEWEB)

Shui, Bin; Evans, Meredydd; Somasundaram, Sriram

2009-04-02

This report is part of a series of reports on building energy efficiency codes in countries associated with the Asian Pacific Partnership (APP) - Australia, South Korea, Japan, China, India, and the United States of America (U.S.). This reports gives an overview of the development of building energy codes in Australia, including national energy policies related to building energy codes, history of building energy codes, recent national projects and activities to promote building energy codes. The report also provides a review of current building energy codes (such as building envelope, HVAC, and lighting) for commercial and residential buildings in Australia.

Country Report on Building Energy Codes in Canada

Energy Technology Data Exchange (ETDEWEB)

Shui, Bin; Evans, Meredydd

2009-04-06

This report is part of a series of reports on building energy efficiency codes in countries associated with the Asian Pacific Partnership (APP) - Australia, South Korea, Japan, China, India, and the United States of America . This reports gives an overview of the development of building energy codes in Canada, including national energy policies related to building energy codes, history of building energy codes, recent national projects and activities to promote building energy codes. The report also provides a review of current building energy codes (such as building envelope, HVAC, lighting, and water heating) for commercial and residential buildings in Canada.

Simulation Tests in Whole Building Heat and Moisture Transfer

DEFF Research Database (Denmark)

Rode, Carsten; Peuhkuri, Ruut Hannele; Woloszyn, Monika

2006-01-01

An important part of the International Energy Agency project, ECBCS, Annex 41 is about modelling the integral heat, air and moisture transfer processes that take place in “whole buildings”. Such modelling deals with all most relevant elements of buildings: The indoor air, the building envelope...

Thermal Performance of Typical Residential Building in Karachi with Different Materials for Construction

Directory of Open Access Journals (Sweden)

Nafeesa Shaheen

2016-04-01

Full Text Available This research work deals with a study of a residential building located in climatic context of Karachi with the objective of being the study of thermal performance based upon passive design techniques. The study helps in reducing the electricity consumption by improving indoor temperatures. The existing residential buildings in Karachi were studied with reference to their planning and design, analyzed and evaluated. Different construction?s compositions of buildings were identified, surveyed and analyzed in making of the effective building envelops. Autodesk® Ecotect, 2011 was used to determine indoor comfort conditions and HVAC (Heating, Ventilation, Air-Conditioning and Cooling loads. The result of the research depicted significant energy savings of 38.5% in HVAC loads with proposed building envelop of locally available materials and glazing.

Cortical processing of dynamic sound envelope transitions.

Science.gov (United States)

Zhou, Yi; Wang, Xiaoqin

2010-12-08

Slow envelope fluctuations in the range of 2-20 Hz provide important segmental cues for processing communication sounds. For a successful segmentation, a neural processor must capture envelope features associated with the rise and fall of signal energy, a process that is often challenged by the interference of background noise. This study investigated the neural representations of slowly varying envelopes in quiet and in background noise in the primary auditory cortex (A1) of awake marmoset monkeys. We characterized envelope features based on the local average and rate of change of sound level in envelope waveforms and identified envelope features to which neurons were selective by reverse correlation. Our results showed that envelope feature selectivity of A1 neurons was correlated with the degree of nonmonotonicity in their static rate-level functions. Nonmonotonic neurons exhibited greater feature selectivity than monotonic neurons in quiet and in background noise. The diverse envelope feature selectivity decreased spike-timing correlation among A1 neurons in response to the same envelope waveforms. As a result, the variability, but not the average, of the ensemble responses of A1 neurons represented more faithfully the dynamic transitions in low-frequency sound envelopes both in quiet and in background noise.

Energy Saving Potential of PCMs in Buildings under Future Climate Conditions

Directory of Open Access Journals (Sweden)

Abdo Abdullah Ahmed Gassar

2017-11-01

Full Text Available Energy consumption reduction under changing climate conditions is a major challenge in buildings design, where excessive energy consumption creates an economic and environmental burden. Improving thermal performance of the buildings through support applying phase change material (PCM is a promising strategy for reducing building energy consumption under future climate change. Therefore, this study aims to investigate the energy saving potentials in buildings under future climate conditions in the humid and snowy regions in the hot continental and humid subtropical climates of the east Asia (Seoul, Tokyo and Hong Kong when various PCMs with different phase change temperatures are applied to a lightweight building envelope. Methodology in this work is implemented in two phases: firstly, investigation of energy saving potentials in buildings through inclusion of three types of PCMs with different phase temperatures into the building envelop separately and use weather file in the present (2017; and, secondly, evaluation of the effect of future climate change on the performance of PCMs by analyzing energy saving potentials of PCMs with 2020, 2050 and 2080 weather data. The results show that the inclusion of PCM into the building envelope is a promising strategy to increase the energy performance in buildings during both heating and cooling seasons in Seoul, Tokyo and Hong Kong under future climate conditions. The energy savings achieved by using PCMs in those regions are electricity savings of 4.48–8.21%, 3.81–9.69%, and 1.94–5.15%, and gas savings of 1.65–16.59%, 7.60–61.76%, and 62.07–93.33% in Seoul, Tokyo and Hong Kong, respectively, for the years 2017, 2020, 2050 and 2080. In addition, BioPCM and RUBITHERMPCM are the most efficient for improving thermal performance and saving energy in buildings in the tested regions and years.

Analysis on exergy consumption patterns for space heating in Slovenian buildings

DEFF Research Database (Denmark)

Dovjak, Mateja; Shukuya, Masanori; Olesen, Bjarne W.

2010-01-01

and demand is taken into consideration. Exergy calculations enable us to analyze how much exergy is consumed in which part, from boiler to building envelope. They also reveal how much energy is supplied for the purpose of heating. Results show that insulation has much bigger effect than effect of boiler...... efficiency. However, the most effective solution is to improve building envelope together with boiler efficiency. Better thermal insulation also makes an important contribution to the improvement of thermal comfort conditions. It causes higher surface temperatures resulting in a larger warm radiant exergy...... emission rate and consequently better thermal comfort....

Advanced Envelope Research for Factory Built Housing, Phase 3. Design Development and Prototyping

Energy Technology Data Exchange (ETDEWEB)

Levy, E. [ARIES Collaborative, New York, NY (United States); Kessler, B. [ARIES Collaborative, New York, NY (United States); Mullens, M. [ARIES Collaborative, New York, NY (United States); Rath, P. [ARIES Collaborative, New York, NY (United States)

2014-01-01

The Advanced Envelope Research effort will provide factory homebuilders with high performance, cost-effective alternative envelope designs. In the near term, these technologies will play a central role in meeting stringent energy code requirements. For manufactured homes, the thermal requirements, last updated by statute in 1994, will move up to the more rigorous IECC 2012 levels in 2013, the requirements of which are consistent with site built and modular housing. This places added urgency on identifying envelope technologies that the industry can implement in the short timeframe. The primary goal of this research is to develop wall designs that meet the thermal requirements based on 2012 IECC standards. Given the affordable nature of manufactured homes, impact on first cost is a major consideration in developing the new envelope technologies. This work is part of a four-phase, multi-year effort. Phase 1 identified seven envelope technologies and provided a preliminary assessment of three selected methods for building high performance wall systems. Phase 2 focused on the development of viable product designs, manufacturing strategies, addressing code and structural issues, and cost analysis of the three selected options. An industry advisory committee helped critique and select the most viable solution to move further in the research -- stud walls with continuous exterior insulation. Phase 3, the subject of the current report, focused on the design development of the selected wall concept and explored variations on the use of exterior foam insulation. The scope also included material selection, manufacturing and cost analysis, and prototyping and testing.

Advanced Envelope Research for Factory Built Housing, Phase 3 -- Design Development and Prototyping

Energy Technology Data Exchange (ETDEWEB)

Levy, E. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Kessler, B. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Mullens, M. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Rath, P. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2014-01-01

The Advanced Envelope Research effort will provide factory homebuilders with high performance, cost-effective alternative envelope designs. In the near term, these technologies will play a central role in meeting stringent energy code requirements. For manufactured homes, the thermal requirements, last updated by statute in 1994, will move up to the more rigorous IECC 2012 levels in 2013, the requirements of which are consistent with site built and modular housing. This places added urgency on identifying envelope technologies that the industry can implement in the short timeframe. The primary goal of this research is to develop wall designs that meet the thermal requirements based on 2012 IECC standards. Given the affordable nature of manufactured homes, impact on first cost is a major consideration in developing the new envelope technologies. This work is part of a four-phase, multi-year effort. Phase 1 identified seven envelope technologies and provided a preliminary assessment of three selected methods for building high performance wall systems. Phase 2 focused on the development of viable product designs, manufacturing strategies, addressing code and structural issues, and cost analysis of the three selected options. An industry advisory committee helped critique and select the most viable solution to move further in the research -- stud walls with continuous exterior insulation. Phase 3, the subject of the current report, focused on the design development of the selected wall concept and explored variations on the use of exterior foam insulation. The scope also included material selection, manufacturing and cost analysis, and prototyping and testing.

Simulation of whole building coupled hygrothermal-airflow transfer in different climates

International Nuclear Information System (INIS)

Qin Menghao; Walton, George; Belarbi, Rafik; Allard, Francis

2011-01-01

The coupled heat, air and moisture transfer between building envelopes and indoor air is complicated, and has a significant influence on the indoor environment and the energy performance of buildings. In the paper, a model for predicting coupled multi-zone hygrothermal-airflow transfer is presented. Both heat and moisture transfer in the building envelope and multi-zone indoor airflow are simultaneously considered; their interactions are modeled. The coupled system model is implemented into Matlab-Simulink, and is validated by using a series of testing tools and experiments. The new program is applied to investigate the moisture transfer effect on indoor air humidity and building energy consumption in different climates (hot-humid, temperate and hot-dry climates). The results show that not accounting for hygrothermal effects in modeling will result in overestimation of energy costs for hot and humid climate situations and possible over sizing of plant leading to inefficient operation.

Application of building envelope energy-saving design in public architecture%建筑围护结构节能设计在公共建筑中的应用

Institute of Scientific and Technical Information of China (English)

杨子江

2012-01-01

以孝感市公共建筑——天工楼为例,根据建筑功能要求和当地气候特点,在建筑单体设计中,合理地确定建筑的朝向、平面形状、外观体型,选用节能建筑材料对建筑围护结构的墙体、屋面、窗户进行节能设计的实践应用,使围护结构的热工参数达到了《公共建筑节能设计标准》(GB50189-2005)的要求,改善了建筑室内热环境,实现了公共建筑减少建筑总能耗50％的目标.%According to the construction of functional requirements and characteristics of local climate, taking Tiangong building of Xiaogan public building as an example, we reasonably determined the orientation, plane shape and appearance physique of the building, and selected the energy - saving building materials to the building envelope wall, roof and windows. The results show that the thermal parameter of enclosure structure meets the requirement of Design Standard for Energy Efficiency of Public (GB50189 -2005), the indoor thermal environment of building is improved and the goal of reducing the total energy consumption 50% of the building is achieved.

All the Universe in an envelope

CERN Multimedia

2007-01-01

Do you know which force is hidden in an envelope or how many billions of years old are the atoms it contains? You will find the answers to these (curious) questions in a post office in the Pays de Gex. The French postal services of the Pays de Gex are again issuing pre-paid envelopes in collaboration with CERN (see Bulletin No. 24/2006). The new series presents some of the concepts of modern physics in an amazing way by showing what you can learn about the Universe with a single envelope. Packets of ten pre-stamped envelopes, each carrying a statement on fundamental physics, will be on sale from 7 July onwards. To learn more about the physics issues presented on the envelopes, people are invited to go to the CERN Web site where they will find the explanations. Five thousand envelopes will be put on sale in July and five thousand more during the French "Fête de la science" in October. They will be available from five post offices in the Pays de Gex (F...

Intelligent Facades for High Performance Green Buildings. Final Technical Report

Energy Technology Data Exchange (ETDEWEB)

Dyson, Anna [Rensselaer Polytechnic Inst., Troy, NY (United States)

2017-03-01

Intelligent Facades for High Performance Green Buildings: Previous research and development of intelligent facades systems has been limited in their contribution towards national goals for achieving on-site net zero buildings, because this R&D has failed to couple the many qualitative requirements of building envelopes such as the provision of daylighting, access to exterior views, satisfying aesthetic and cultural characteristics, with the quantitative metrics of energy harvesting, storage and redistribution. To achieve energy self-sufficiency from on-site solar resources, building envelopes can and must address this gamut of concerns simultaneously. With this project, we have undertaken a high-performance building- integrated combined-heat and power concentrating photovoltaic system with high temperature thermal capture, storage and transport towards multiple applications (BICPV/T). The critical contribution we are offering with the Integrated Concentrating Solar Façade (ICSF) is conceived to improve daylighting quality for improved health of occupants and mitigate solar heat gain while maximally capturing and transferring on- site solar energy. The ICSF accomplishes this multi-functionality by intercepting only the direct-normal component of solar energy (which is responsible for elevated cooling loads) thereby transforming a previously problematic source of energy into a high- quality resource that can be applied to building demands such as heating, cooling, dehumidification, domestic hot water, and possible further augmentation of electrical generation through organic Rankine cycles. With the ICSF technology, our team is addressing the global challenge in transitioning commercial and residential building stock towards on-site clean energy self-sufficiency, by fully integrating innovative environmental control systems strategies within an intelligent and responsively dynamic building envelope. The advantage of being able to use the entire solar spectrum for

The influence of ventilated façade on sound insulation properties of envelope walls

Directory of Open Access Journals (Sweden)

Fišarová Zuzana

2017-01-01

Full Text Available Presented article deals with sound insulation properties of timber structures’ envelope walls. Particularly, the influence of heavy board ventilated façade on laboratory airborne sound insulation R and Rw in dB was studied. The installation method and gaps between façade boards can cause building defects originating in overrating the influence of ventilated cladding on envelope wall acoustic parameters. Real constructions were built for the experimental purposes and measurements, one with gaps between boards and one with simply eliminated gaps for mutual comparison. The results obtained were processed to make tables and graphs and to derive recommendations for the design of this type of constructions involving the general installation method of façade boards. Detailed results are depicted in conclusions.

Measures for energy efficiency improvement of buildings

Directory of Open Access Journals (Sweden)

Vukadinović Ana V.

2015-01-01

Full Text Available The increase in energy consumption in buildings causes the need to propose energy efficiency improvement measures. Urban planning in accordance with micro location conditions can lead to energy consumption reduction in buildings through the passive solar design. While satisfying the thermal comfort to the user space purpose, energy efficiency can be achieved by optimizing the architectural and construction parameters such as shape of the building, envelope structure and the percentage of glazing. The improvement of the proposed measures, including the use of renewable energy sources, can meet requirements of Directive 2010/31 / EU of 'nearly zero energy buildings'.

Radiative transfer in spherical circumstellar dust envelopes. III. Dust envelope models of some well known infrared stars

International Nuclear Information System (INIS)

Apruzese, J.P.

1975-01-01

The radiative transfer techniques described elsewhere by the author have been employed to construct dust envelope models of several well known infrared stars. The resulting calculations indicate that the infrared emissivity of circumstellar grains generally must be higher than that which many calculations of small nonsilicate grains yield. This conclusion is dependent to some degree on the (unknown) size of the stellar envelopes considered, but is quite firm in the case of the spatially resolved envelope of IRC+10216. Further observations of the spatial distribution of the infrared radiation from stellar envelopes will be invaluable in deciphering the properties of the circumstellar grains

Biocompuestos para perfiles avanzados adaptados a la edificación = Biocomposites for Advanced Profiles Adapted to Building Envelope

Directory of Open Access Journals (Sweden)

I. Roig

2016-04-01

Full Text Available Compuestos alternativos en el sector de la envolvente se obtienen por extrusión de estirado de secciones y perfiles de panel de enclavamiento estrechas. Estos elementos estructurales, resistentes al impacto, tienen la ventaja de una instalación más rápida y segura, y su diseño modular les hace idóneos para muchos edificios y otras aplicaciones. Un desarrollo adicional en esta área puede ser la obtención de una alternativa sostenible a los perfiles compuestos actuales. Estudios anteriores han demostrado que los compuestos fabricados a partir de materiales naturales tales como fibras y polímeros bio-derivados, ofrecen una alternativa sostenible a los polímeros y materiales compuestos tradicionales. El objetivo de este desarrollo es reemplazar el típico perfil de acero ligero. Los perfiles de acabado también se pueden utilizar para terminar tabiques de mampostería existentes, revestimiento de ejes mecánicos y de extracción y revestimiento de la columna. Los perfiles se han diseñado utilizando bio-polímeros, reforzados con fibras naturales. Se han establecido los parámetros de procesamiento y las formulaciones apropiadas de bioresina y fibras naturales. También se ha evaluado la adaptación de las técnicas de procesamiento de pultrusión existentes a las características concretas de los nuevos biomateriales y fibras naturales. Como resultado, los perfiles de pultrusión adaptados a la construcción se han desarrollado con la incorporación de nuevos materiales y biomateriales basados en resina. Abstract An alternative composites answer in the envelope sector is the fabrication by pultrusion of narrow interlocking panel sections and profiles. These impact-resistant structural elements have the advantage of quicker, safer installation and their modular design equally answers many identical building and other applications¡Error! No se encuentra el origen de la referencia.. An additional development in this area can be the

Estimating envelope thermal characteristics from single point in time thermal images

Science.gov (United States)

Alshatshati, Salahaldin Faraj

Energy efficiency programs implemented nationally in the U.S. by utilities have rendered savings which have cost on average 0.03/kWh. This cost is still well below generation costs. However, as the lowest cost energy efficiency measures are adopted, this the cost effectiveness of further investment declines. Thus there is a need to more effectively find the most opportunities for savings regionally and nationally, so that the greatest cost effectiveness in implementing energy efficiency can be achieved. Integral to this process. are at scale energy audits. However, on-site building energy audits process are expensive, in the range of US1.29/m2-$5.37/m2 and there are an insufficient number of professionals to perform the audits. Energy audits that can be conducted at-scale and at low cost are needed. Research is presented that addresses at community-wide scales characterization of building envelope thermal characteristics via drive-by and fly-over GPS linked thermal imaging. A central question drives this research: Can single point-in-time thermal images be used to infer U-values and thermal capacitances of walls and roofs? Previous efforts to use thermal images to estimate U-values have been limited to rare steady exterior weather conditions. The approaches posed here are based upon the development two models first is a dynamic model of a building envelope component with unknown U-value and thermal capacitance. The weather conditions prior to the thermal image are used as inputs to the model. The model is solved to determine the exterior surface temperature, ultimately predicted the temperature at the thermal measurement time. The model U-value and thermal capacitance are tuned in order to force the error between the predicted surface temperature and the measured surface temperature from thermal imaging to be near zero. This model is developed simply to show that such a model cannot be relied upon to accurately estimate the U-value. The second is a data

Procedures when calculating economy for building envelopes in Denmark

DEFF Research Database (Denmark)

Rudbeck, Claus Christian; Svendsen, Sv Aa Højgaard

1999-01-01

of using total-economy. Total-economy incorporates all present and future investments (e.g. operational and maintenance costs) into one number making it possible to invest more money when constructing a building and save the money later on due to lower cost for maintenance and energy consumption.This paper...

Technical - Economic Research for Passive Buildings

Science.gov (United States)

Miniotaite, Ruta

2017-10-01

A newly constructed passive house must save 80 % of heat resources; otherwise it is not a passive house. The heating energy demand of a passive building is less than 15 kWh/m2 per year. However, a passive house is something more than just an energy-saving house. This concept involves sustainable, high-quality, valuable, healthy and durable construction. Features of a passive house: high insulation of envelope components, high-quality windows, good tightness of the building, regenerative ventilation system and elimination of thermal bridges. The Energy Performance of Buildings Directive (EPBD) 61 requires all new public buildings to become near-zero energy buildings by 2019 and will be extended to all new buildings by 2021. This concept involves sustainable, high-quality, valuable, healthy and durable construction. Foundation, walls and roofs are the most essential elements of a house. The type of foundation for a private house is selected considering many factors. The article examines technological and structural solutions for passive buildings foundation, walls and roofs. The technical-economic comparison of the main structures of a passive house revealed that it is cheaper to install an adequately designed concrete slab foundation than to build strip or pile foundation and the floor separately. Timber stud walls are the cheapest wall option for a passive house and 45-51% cheaper compared to other options. The comparison of roofs and ceilings showed that insulation of the ceiling is 25% more efficient than insulation of the roof. The comparison of the main envelope elements efficiency by multiple-criteria evaluation methods showed that it is economically feasible to install concrete slab on ground foundation, stud walls with sheet cladding and a pitched roof with insulated ceiling.

Performance analysis of an energy efficient building prototype by using TRNSYS

OpenAIRE

Lai, Kun; Wang, Wen; Giles, Harry

2014-01-01

Buildings section accouts for a large part of the total primary energy consumption. This paper reports a simulative study on an energy efficient building prototype named MIDMOD by using TRNSYS program. The prototype is a new genre of affordable medium density building concepts that are more adaptable, durable, and energy efficient as whole-life housing typologies than those currently available.The building envelope thermal insulation and air tightness are enhanced to reduce heat loss. Several...

Building Integrated Photovoltaics: A Concise Description of the Current State of the Art and Possible Research Pathways

Directory of Open Access Journals (Sweden)

Bjørn Petter Jelle

2015-12-01

Full Text Available Building integrated photovoltaics (BIPV offer an aesthetical, economical and technical solution to integrate solar cells harvesting solar radiation to produce electricity within the climate envelopes of buildings. Photovoltaic (PV cells may be mounted above or onto the existing or traditional roofing or wall systems. However, BIPV systems replace the outer building envelope skin, i.e., the climate screen, hence serving simultanously as both a climate screen and a power source generating electricity. Thus, BIPV may provide savings in materials and labor, in addition to reducing the electricity costs. Hence, for the BIPV products, in addition to specific requirements put on the solar cell technology, it is of major importance to have satisfactory or strict requirements of rain tightness and durability, where building physical issues like e.g., heat and moisture transport in the building envelope also have to be considered and accounted for. This work, from both a technological and scientific point of view, summarizes briefly the current state-of-the-art of BIPV, including both BIPV foil, tiles, modules and solar cell glazing products, and addresses possible research pathways for BIPV in the years to come.

14 CFR 29.87 - Height-velocity envelope.

Science.gov (United States)

2010-01-01

... Category A engine isolation requirements, the height-velocity envelope for complete power failure must be... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Height-velocity envelope. 29.87 Section 29... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Flight Performance § 29.87 Height-velocity envelope. (a...

Description of case houses. Building integrated energy supply; Beskrivelse af casehuse. Bygningsintegreret energiforsyning

Energy Technology Data Exchange (ETDEWEB)

Jensen, Rasmus L.; Noergaard, J.; Daniels, O.; Justesen, R.O.

2011-08-15

In the future, buildings will not only act as consumers of energy but as producers as well. For these ''prosumers'', energy production by use of solar panels, photovoltaics and heat pumps etc will be essential. The objective of this project was to find the most optimal combinations of building insulation and use of renewable energy sources in existing buildings in terms of economics and climate impacts. Five houses were analyzed based on different personal load, consumption profiles, solar orientation and proposed building envelope improvements and use of combinations of renewable energy systems. The present report describes typical construction details of the building envelope (windows, floor, outside wall and roof/ceiling) for houses built in the years 1961-1972, 1973-1978 and 1979-1998. Furthermore the report describes the necessary improvements for the buildings' U-value to be the minimum value as stated in the Danish building code of 2010, and to be the values for buildings at the level of low-energy class 2015. Cost estimation for optimizing the houses to an optimum insulation level has been made. (ln)

Assessment of energy and economic performance of office building models: a case study

Science.gov (United States)

Song, X. Y.; Ye, C. T.; Li, H. S.; Wang, X. L.; Ma, W. B.

2016-08-01

Energy consumption of building accounts for more than 37.3% of total energy consumption while the proportion of energy-saving buildings is just 5% in China. In this paper, in order to save potential energy, an office building in Southern China was selected as a test example for energy consumption characteristics. The base building model was developed by TRNSYS software and validated against the recorded data from the field work in six days out of August-September in 2013. Sensitivity analysis was conducted for energy performance of building envelope retrofitting; five envelope parameters were analyzed for assessing the thermal responses. Results indicated that the key sensitivity factors were obtained for the heat-transfer coefficient of exterior walls (U-wall), infiltration rate and shading coefficient (SC), of which the sum sensitivity factor was about 89.32%. In addition, the results were evaluated in terms of energy and economic analysis. The analysis of sensitivity validated against some important results of previous studies. On the other hand, the cost-effective method improved the efficiency of investment management in building energy.

Whole-Building Hygrothermal Modeling in IEA Annex 41

DEFF Research Database (Denmark)

Rode, Carsten; Woloszyn, Monika

2007-01-01

. The IEA Annex 41 project runs from 2004–2007, coming to conclusion just before the Thermal Performance of the Exterior Envelopes of Whole Buildings X conference. The Annex 41 project and its Subtask 1 do not aim to produce one state-of-the-art hygrothermal simulation model for whole buildings, but rather...... the modeling, free scientific contributions have been invited from specific fields that need the most attention in order to better accomplish the integral building simulations. This paper will give an overview of the advances in whole-building hygrothermal simulation that have been accomplished and presented...

Solitary Alfven wave envelopes and the modulational instability

International Nuclear Information System (INIS)

Kennel, C.F.

1987-06-01

The derivative nonlinear Schroedinger equation describes the modulational instability of circularly polarized dispersive Alfven wave envelopes. It also may be used to determine the properties of finite amplitude localized stationary wave envelopes. Such envelope solitons exist only in conditions of modulational stability. This leaves open the question of whether, and if so, how, the modulational instability produces envelope solitons. 12 refs

PCM/wood composite to store thermal energy in passive building envelopes

Science.gov (United States)

Barreneche, C.; Vecstaudza, J.; Bajare, D.; Fernandez, A. I.

2017-10-01

The development of new materials to store thermal energy in a passive building system is a must to improve the thermal efficiency by thermal-regulating the indoor temperatures. This fact will deal with the reduction of the gap between energy supply and energy demand to achieve thermal comfort in building indoors. The aim of this work was to test properties of novel PCM/wood composite materials developed at Riga Technical University. Impregnation of PCM (phase change material) in wood increases its thermal mass and regulates temperature fluctuations during day and night. The PCM used are paraffin waxes (RT-21 and RT-27 from Rubitherm) and the wood used was black alder, the most common wood in Latvia. The PCM distribution inside wood sample has been studied as well as its thermophysical, mechanical and fire reaction properties. Developed composite materials are promising in the field of energy saving in buildings.

Building Technologies Program Multi-Year Program Plan Research and Development 2008

Energy Technology Data Exchange (ETDEWEB)

None, None

2008-01-01

Building Technologies Program Multi-Year Program Plan 2008 for research and development, including residential and commercial integration, lighting, HVAC and water heating, envelope, windows, and analysis tools.

Country Report on Building Energy Codes in the United States

Energy Technology Data Exchange (ETDEWEB)

Halverson, Mark A.; Shui, Bin; Evans, Meredydd

2009-04-30

This report is part of a series of reports on building energy efficiency codes in countries associated with the Asian Pacific Partnership (APP) - Australia, South Korea, Japan, China, India, and the United States of America (U.S.). This reports gives an overview of the development of building energy codes in U.S., including national energy policies related to building energy codes, history of building energy codes, recent national projects and activities to promote building energy codes. The report also provides a review of current building energy codes (such as building envelope, HVAC, lighting, and water heating) for commercial and residential buildings in the U.S.

Genetic Diversity of Koala Retroviral Envelopes

Directory of Open Access Journals (Sweden)

Wenqin Xu

2015-03-01

Full Text Available Genetic diversity, attributable to the low fidelity of reverse transcription, recombination and mutation, is an important feature of infectious retroviruses. Under selective pressure, such as that imposed by superinfection interference, gammaretroviruses commonly adapt their envelope proteins to use alternative receptors to overcome this entry block. The first characterized koala retroviruses KoRV subgroup A (KoRV-A were remarkable in their absence of envelope genetic variability. Once it was determined that KoRV-A was present in all koalas in US zoos, regardless of their disease status, we sought to isolate a KoRV variant whose presence correlated with neoplastic malignancies. More than a decade after the identification of KoRV-A, we isolated a second subgroup of KoRV, KoRV-B from koalas with lymphomas. The envelope proteins of KoRV-A and KoRV-B are sufficiently divergent to confer the ability to bind and employ distinct receptors for infection. We have now obtained a number of additional KoRV envelope variants. In the present studies we report these variants, and show that they differ from KoRV-A and KoRV-B envelopes in their host range and superinfection interference properties. Thus, there appears to be considerable variation among KoRVs envelope genes suggesting genetic diversity is a factor following the KoRV-A infection process.

14 CFR 27.87 - Height-speed envelope.

Science.gov (United States)

2010-01-01

... applicable power failure condition in paragraph (b) of this section, a limiting height-speed envelope must be... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Height-speed envelope. 27.87 Section 27.87... STANDARDS: NORMAL CATEGORY ROTORCRAFT Flight Performance § 27.87 Height-speed envelope. (a) If there is any...

Integrated evaluation of radiative heating systems for residential buildings

International Nuclear Information System (INIS)

Anastaselos, Dimitrios; Theodoridou, Ifigeneia; Papadopoulos, Agis M.; Hegger, Manfred

2011-01-01

Based on the need to reduce CO 2 emissions and minimize energy dependency, the EU Member States have set ambitious energy policies goals and have developed respective, specific regulations, in order to improve the energy performance of the building sector. Thus, specific measures regarding the buildings' envelope, the use of efficient HVAC technologies and the integration of renewable energy systems are being constantly studied and promoted. The effective combination of these three main aspects will consequently result in maximum energy efficiency. Germany has played a key role in this development, with intensive work focusing in the improvement of the energy behaviour of the residential building stock. In this paper, the use of radiative heating systems placing special emphasis on infrared is being studied as part of the energy renovation of residential buildings from the 1970's. This is done by applying an integrated assessment model to evaluate specific interventions regarding the improvement of the energy behaviour of the buildings' envelope and the use of radiative heating systems, based on a thorough Life Cycle Analysis according to criteria of energy, economic and environmental performance, as well as thermal comfort. -- Highlights: → Assessment of energy, economic and environmental performance of heating systems. → Life Cycle Analysis in combination with the quality of thermal comfort. → Effectiveness of interventions in already partially insulated buildings.

Optimal control and performance of photovoltachromic switchable glazing for building integration in temperate climates

International Nuclear Information System (INIS)

Favoino, Fabio; Fiorito, Francesco; Cannavale, Alessandro; Ranzi, Gianluca; Overend, Mauro

2016-01-01

Highlights: • The features and properties of photovoltachromic switchable glazing are presented. • The different possible control strategies for the switchable glazing are presented. • Thermal and daylight performance are co-simulated for rule-based and optimal control. • A novel building performance simulation framework is developed for this aim. • Switchable glazing performance is compared for different controls and climates. - Abstract: The development of adaptive building envelope technologies, and particularly of switchable glazing, can make significant contributions to decarbonisation targets. It is therefore essential to quantify their effect on building energy use and indoor environmental quality when integrated into buildings. The evaluation of their performance presents new challenges when compared to conventional “static” building envelope systems, as they require design and control aspects to be evaluated together, which are also mutually interrelated across thermal and visual physical domains. This paper addresses these challenges by presenting a novel simulation framework for the performance evaluation of responsive building envelope technologies and, particularly, of switchable glazing. This is achieved by integrating a building energy simulation tool and a lighting simulation one, in a control optimisation framework to simulate advanced control of adaptive building envelopes. The performance of a photovoltachromic glazing is evaluated according to building energy use, Useful Daylight Illuminance, glare risk and load profile matching indicators for a sun oriented office building in different temperate climates. The original architecture of photovoltachromic cell provides an automatic control of its transparency as a function of incoming solar irradiance. However, to fully explore the building integration potential of photovoltachromic technology, different control strategies are evaluated, from passive and simple rule based controls, to

Economic Energy Savings Potential in Federal Buildings

Energy Technology Data Exchange (ETDEWEB)

Brown, Daryl R.; Dirks, James A.; Hunt, Diane M.

2000-09-04

The primary objective of this study was to estimate the current life-cycle cost-effective (i.e., economic) energy savings potential in Federal buildings and the corresponding capital investment required to achieve these savings, with Federal financing. Estimates were developed for major categories of energy efficiency measures such as building envelope, heating system, cooling system, and lighting. The analysis was based on conditions (building stock and characteristics, retrofit technologies, interest rates, energy prices, etc.) existing in the late 1990s. The potential impact of changes to any of these factors in the future was not considered.

Assessment of infiltration heat recovery and its impact on energy consumption for residential buildings

International Nuclear Information System (INIS)

Solupe, Mikel; Krarti, Moncef

2014-01-01

Highlights: • Five steady-state air infiltration heat recovery or IHR models are described and compared. • IHR models are incorporated within whole-building simulation analysis tool. • IHR can reduce the thermal loads of residential buildings by 5–30%. - Abstract: Infiltration is a major contributor to the energy consumption of buildings, particularly in homes where it accounts for one-third of the heating and cooling loads. Traditionally, infiltration is calculated independent of the building envelope performance, however, it has been established that a thermal coupling exists between the infiltration and conduction heat transfer of the building envelope. This effect is known as infiltration heat recovery (IHR). Experiments have shown that infiltration heat recovery can typically reduce the infiltration thermal load by 10–20%. Currently, whole-building energy simulation tools do not account for the effect of infiltration heat recovery on heating and cooling loads. In this paper, five steady-state IHR models are described to account for the thermal interaction between infiltration air and building envelope components. In particular, inter-model and experimental comparisons are carried out to assess the prediction accuracy of five IHR models. In addition, the results from a series of sensitivity analyses are presented, including an evaluation of the predictions for heating energy use associated with four audited homes obtained from whole-building energy simulation analysis with implemented infiltration heat recovery models. Experimental comparison of the IHR models reveal that the predictions from all the five models are consistent and are within 2% when 1-D flow and heat transfer conditions are considered. When implementing IHR models to a whole-building simulation environment, a reduction of 5–30% in heating consumption is found for four audited residential homes

Injection envelope matching in storage rings

International Nuclear Information System (INIS)

Minty, M.G.; Spence, W.L.

1995-05-01

The shape and size of the transverse phase space injected into a storage ring can be deduced from turn-by-turn measurements of the transient behavior of the beam envelope in the ring. Envelope oscillations at 2 x the β-tron frequency indicate the presence of a β-mismatch, while envelope oscillations at the β-tron frequency are the signature of a dispersion function mismatch. Experiments in injection optimization using synchrotron radiation imaging of the beam and a fast-gated camera at the SLC damping rings are reported

Envelope Protection for In-Flight Ice Contamination

Science.gov (United States)

Gingras, David R.; Barnhart, Billy P.; Ranaudo, Richard J.; Ratvasky, Thomas P.; Morelli, Eugene A.

2010-01-01

Fatal loss-of-control (LOC) accidents have been directly related to in-flight airframe icing. The prototype system presented in this paper directly addresses the need for real-time onboard envelope protection in icing conditions. The combinations of a-priori information and realtime aerodynamic estimations are shown to provide sufficient input for determining safe limits of the flight envelope during in-flight icing encounters. The Icing Contamination Envelope Protection (ICEPro) system has been designed and implemented to identify degradations in airplane performance and flying qualities resulting from ice contamination and provide safe flight-envelope cues to the pilot. Components of ICEPro are described and results from preliminary tests are presented.

Thermal Activated Envelope

DEFF Research Database (Denmark)

Foged, Isak Worre; Pasold, Anke

2015-01-01

The research studies the making of a responsive architectural envelope based on bi-materials. The bi-materials are organized according to a method that combines different isotropic metals and plastic into an active composite structure that reacts to temperature variations. Through an evolutionary......, environmental dynamics and occupancy dynamics. Lastly, a physical prototype is created, which illustrates the physical expression of the bi-materials and the problems related to manufacturing of these composite structures.......The research studies the making of a responsive architectural envelope based on bi-materials. The bi-materials are organized according to a method that combines different isotropic metals and plastic into an active composite structure that reacts to temperature variations. Through an evolutionary...

Biomimicry of Palm Tree Leaves Form and Pattern on Building Form

Directory of Open Access Journals (Sweden)

Agus Salim N.A.

2014-01-01

Full Text Available This article is a study on biomimicry of palm tree towards a building form. It is to find a suitable form and pattern that can be applied to building shell to ease building maintenance operation beside to enhance the aesthetic value of a building architecture. The research has been carried out by observation and modeling on some various species of palm tree’s patterns and forms. The result expectation can be found at the end of this research by producing the best pattern of palm tree that can be adapted to building envelop as the whole form of a building.

The South Carolina bridge-scour envelope curves

Science.gov (United States)

Benedict, Stephen T.; Feaster, Toby D.; Caldwell, Andral W.

2016-09-30

The U.S. Geological Survey, in cooperation with the South Carolina Department of Transportation, conducted a series of three field investigations to evaluate historical, riverine bridge scour in the Piedmont and Coastal Plain regions of South Carolina. These investigations included data collected at 231 riverine bridges, which lead to the development of bridge-scour envelope curves for clear-water and live-bed components of scour. The application and limitations of the South Carolina bridge-scour envelope curves were documented in four reports, each report addressing selected components of bridge scour. The current investigation (2016) synthesizes the findings of these previous reports into a guidance manual providing an integrated procedure for applying the envelope curves. Additionally, the investigation provides limited verification for selected bridge-scour envelope curves by comparing them to field data collected outside of South Carolina from previously published sources. Although the bridge-scour envelope curves have limitations, they are useful supplementary tools for assessing the potential for scour at riverine bridges in South Carolina.

New building envelope structures. Energy saving and moisture technology; Uudet vaipparakenteet. Energian saeaestoe ja kosteustekniikka

Energy Technology Data Exchange (ETDEWEB)

Kokko, E.; Ojanen, T.; Salonvaara, M. [VTT Building Technology, Espoo (Finland). Building Physics, Building Services and Fire Technology

1997-12-31

The publication summarizes the results that deal with reducing heating energy loss through building envelopes, improving hygric (moisture) behavior of structures and utilization solar energy. The objective was to produce new innovative structures and principles of applications for low-energy houses. The applications with the purpose of reducing heating energy consumption are based on conventional mineral wool and cellular plastic insulation materials, low-emissivity foils and coatings that reduce long-wave thermal radiation and building papers with desired properties. Utilization of solar energy was investigated with a solar energy collector system consisting of transparent insulation and glass layers, air circulation with natural convection and thermal mass. Thick light-weight mineral wool insulation layers in the exterior walls are in practice always somewhat non-ideal which increases convection air flows in or through the walls when compared to ideal structures. Increasing the thickness of the insulation layer makes it more non-ideal and thus susceptible to drawbacks of convection flows. Furthermore the internal moisture in the structure is distributed unevenly increasing the risk for mold growth and rotting. The convection effects in thick walls can be eliminated by isolating the insulation layers with air tight but vapor permeable vertical convection barriers. Significant portion of the total heat transfer in light-weight mineral wool insulation is caused by long-wave radiation (Infrared Radiation - IR). A low-emissivity foil attached directly to a surface of a mineral wool insulation has only a small effect on the thermal resistance of the whole insulation layer. Radiation inside thick insulation layers can be reduced significantly only by making use of fibers with low-emissivity surfaces or fibers transparent to IR-radiation and using low-emissivity foils on the sides of the layers. A `real life` structure consisting of a thick light-weight mineral wool

Evolution of envelope solitons of ionization waves

International Nuclear Information System (INIS)

Ohe, K.; Hashimoto, M.

1985-01-01

The time evolution of a particle-like envelope soliton of ionization waves in plasma was investigated theoretically. The hydrodynamic equations of one spatial dimension were solved and the nonlinear dispersion relation was derived. For the amplitude of the wave the nonlinear Schroedinger equation was derived. Its soliton solution was interpreted as the envelope soliton which was experimentally found. The damping rate of the envelope soliton was estimated. (D.Gy.)

A Low-energy Building under Arctic Conditions - Experiences After Five Years of Operation

DEFF Research Database (Denmark)

Rode, Carsten; Vladyková, Petra; Kotol, Martin

2011-01-01

In 2005, a low energy house was inaugurated in Sisimiut, Greenland. The house and the plans with it were presented at the third International Building Physics Conference in 2006. The house is characterised by having a highly insulated building envelope which is almost free of thermal bridges, adv...

Effect of Various External Shading Devices on Windows for Minimum Heat Gain and Adequate Day lighting into Buildings of Hot and Dry Climatic Zone in India

Directory of Open Access Journals (Sweden)

Kirankumar Gorantla

2018-01-01

Full Text Available Glass is the major component of the building envelope to provide visual comfort to inside the buildings. In général clear and bronze glass was used as a main building envelope for both residential and commercial buildings to provide better day lighting into the buildings. If we use more glass area as a building envelope more radiation allows into the buildings. So that it is necessary to reduce more solar radiation and provide sufficient daylight factor inside the building's through glass windows with the help of external devices called shading devices. In this work four shading devices was tried on bronze glass window to find the heat gain and daylighting into buildings. This paper presents the experimental measurement of spectral characteristics of bronze glass which include transmission and reflection in entire solar spectrum region (300nm-2500nm based on ASTM standards. A MATLAB code was developed to compute visible and solar optical properties as per the British standards. A building model was designed by design builder software tool. 40% window to wall ratio was considered for building models, thermal and day lighting analysis of buildings through windows was carried out in Energy plus software tool for hot and dry climatic zone of India.

Active House: an all active eco-architecture building envelope concept

NARCIS (Netherlands)

Zeiler, W.

2008-01-01

The present trend in energy efficient eco-architecture dwellings is the passive house concept. The ventilation of many of these passive houses is critical. The development of sustainable buildings is driven by the need to preserve the balance of nature. The ventilation of many of these passive

Data on European non-residential buildings.

Science.gov (United States)

D'Agostino, Delia; Cuniberti, Barbara; Bertoldi, Paolo

2017-10-01

This data article relates to the research paper Energy consumption and efficiency technology measures in European non-residential buildings (D'Agostino et al., 2017) [1]. The reported data have been collected in the framework of the Green Building Programme that ran from 2006 to 2014. The project has encouraged the adoption of efficiency measures to boost energy savings in European non-residential buildings. Data focus on the one-thousand buildings that joined the Programme allowing to save around 985 GWh/year. The main requirement to join the Programme was the reduction of at least 25% primary energy consumption in a new or retrofitted building. Energy consumption before and after the renovation are provided for retrofitted buildings while, in new constructions, a building had to be designed using at least 25% less energy than requested by the country's building codes. The following data are linked within this article: energy consumption, absolute and relative savings related to primary energy, saving percentages, implemented efficiency measures and renewables. Further information is given about each building in relation to geometry, envelope, materials, lighting and systems.

Green, Clean, & Mean: Pushing the Energy Envelope in Tech Industry Buildings

Energy Technology Data Exchange (ETDEWEB)

Mills, Evan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Granderson, Jessica [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chan, Rengie [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Diamond, Richard [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Haves, Philip [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Nordman, Bruce [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mathew, Paul [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Piette, Mary Ann [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Robinson, Gerald [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Selkowitz, Stephen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2015-05-01

When it comes to innovation in energy and building performance, one can expect leading-edge activity from the technology sector. As front-line innovators in design, materials science, and information management, developing and operating high-performance buildings is a natural extension of their core business. The energy choices made by technology companies have broad importance given their influence on society at large as well as the extent of their own energy footprint. Microsoft, for example, has approximately 250 facilities around the world (30 million square feet of floor area), with significant aggregate energy use of approximately 4 million kilowatt-hours per day (Figure 1).

The Impact of Insulation and HVAC Degradation on Overall Building Energy Performance: A Case Study

Directory of Open Access Journals (Sweden)

Georgios Eleftheriadis

2018-02-01

Full Text Available Through monitoring of buildings, it can be proven that the performance of envelope elements and energy supply systems deteriorates with time. The results of this degradation are higher energy consumption and life cycle costs than projected in the building design phase. This paper considers the impacts of this deterioration on the whole building energy performance with the goal of improving the accuracy of long term performance calculations. To achieve that, simplified degradation equations found in literature are applied on selected envelope elements and heating system components of a single-family house in Germany. The energy performance of the building over 20 years is determined through simulations by EnergyPlus and MATLAB. The simulation results show that, depending on maintenance and primary heating system, the building can consume between 18.4% and 47.1% more primary energy over 20 years compared to a scenario in which no degradation were to occur. Thus, it can be concluded that considering performance drop with time is key in order to improve the decision-making process when designing future-proof buildings.

Thermal Inertia Performance Evaluation of Light-Weighted Construction Space Envelopes Using Phase Change Materials in Mexico City’s Climate

Directory of Open Access Journals (Sweden)

Adriana Lira-Oliver

2017-10-01

Full Text Available The present study’s main objective was to determine the applicability of organic phase change materials (PCMs in a building’s envelope construction system for the passive provision of comfortable indoor thermal conditions over one year based on thermal inertia in Mexico City. Research on PCMs relate mainly to their use in building envelope construction systems to reduce energy consumption for mechanical indoor thermal conditioning—not in passive systems. Computer simulation results of mean indoor temperature variations are presented with the objective of evaluating these construction systems’ thermal inertia properties. In the present study, dynamic thermal simulations (DTS, using EnergyPlus software, of ten 1 m3 test units with envelope construction systems combining organic PCMs of different fusion temperatures with conventional materials were performed. Based on the results, it is concluded that the implementation of organic PCMs with a fusion temperature around 25 °C in combination with aerated concrete in a space envelope results in the highest number of hours the indoor temperatures remain within the comfort range throughout a typical year, due to the decrement of indoor temperature oscillations and, to a large extent, to thermal lag.

Seismic upgrade of building 776/777 at Rocky Flats Plant using latest edition of UCRL-15910

International Nuclear Information System (INIS)

Gillengerten, J.D.; Hamburger, R.O.; Keith, S.R.; McGovern, L.J.

1991-01-01

Building 776/777 is a large two-story structure used in the processing and decontamination of radioactively contaminated materials, tools, and equipment. Originally constructed in the 1950s, the building has been expanded several times and, following a major fire, was provided with a second structural roof to enclose the building envelope. Overall building dimensions are approximately 300 by 600 feet. It uses steel-frame construction with partially restrained joints for transverse moment resistance and diagonal braces for longitudinal stability. The second floor is a formed slab on steel framing, and the roof is a metal deck system. Exterior enclosures include poorly reinforced concrete-block masonry and cement-asbestos siding. Rigid concrete elements, forming vaults for materials with high radiation hazard, are present in some areas. The building was previously identified as having low resistance to both seismic and high-wind/tornado loads. A structural seismic upgrade was designed for the building, according to the provisions of US Department of Energy criteria document UCRL-15910, for high-hazard facilities. This design is intended to prevent substantial breach of the building envelope. The design supplements the lateral capacity of the existing semirigid steel frames with a series of steel buttress frames and exterior drag elements. This feature minimizes the extent of construction within secure and hazardous areas of the building but induces significant thermal stresses. Unique aspects of the design include provision for thermal relief as well as development of strengthening and anchorage of masonry walls that can accommodate large expected inelastic building drifts. This design illustrates the Department of Energy's newly adopted criteria, as applied to existing structures. It also indicates methods that may be used for strengthening hazardous and sensitive structures without significant work within the building envelope

200 Area Deactivation Project Facilities Authorization Envelope Document

International Nuclear Information System (INIS)

DODD, E.N.

2000-01-01

Project facilities as required by HNF-PRO-2701, Authorization Envelope and Authorization Agreement. The Authorization Agreements (AA's) do not identify the specific set of environmental safety and health requirements that are applicable to the facility. Therefore, the facility Authorization Envelopes are defined here to identify the applicable requirements. This document identifies the authorization envelopes for the 200 Area Deactivation

Building energy performance analysis by an in-house developed dynamic simulation code: An investigation for different case studies

International Nuclear Information System (INIS)

Buonomano, Annamaria; Palombo, Adolfo

2014-01-01

Highlights: • A new dynamic simulation code for building energy performance analysis is presented. • The thermal behavior of each building element is modeled by a thermal RC network. • The physical models implemented in the code are illustrated. • The code was validated by the BESTEST standard procedure. • We investigate residential buildings, offices and stores in different climates. - Abstract: A novel dynamic simulation model for the building envelope energy performance analysis is presented in this paper. This tool helps the investigation of many new building technologies to increase the system energy efficiency and it can be carried out for scientific research purposes. In addition to the yearly heating and cooling load and energy demand, the obtained output is the dynamic temperature profile of indoor air and surfaces and the dynamic profile of the thermal fluxes through the building elements. The presented simulation model is also validated through the BESTEST standard procedure. Several new case studies are developed for assessing, through the presented code, the energy performance of three different building envelopes with several different weather conditions. In particular, dwelling and commercial buildings are analysed. Light and heavyweight envelopes as well as different glazed surfaces areas have been used for every case study. With the achieved results interesting design and operating guidelines can be obtained. Such data have been also compared vs. those calculated by TRNSYS and EnergyPlus. The detected deviation of the obtained results vs. those of such standard tools are almost always lower than 10%

Analysis on exergy consumption patterns for space heating in Slovenian buildings

International Nuclear Information System (INIS)

Dovjak, Mateja; Shukuya, Masanori; Olesen, Bjarne W.; Krainer, Ales

2010-01-01

Problem of high energy use for heating in Slovenian buildings is analyzed with exergy and energy analysis. Results of both are compared and discussed. Three cases of exterior building walls are located in three climatic zones in winter conditions. Results of energy analyses show that the highest heating energy demand appears in the case with less thermal insulation, especially in colder climate. If the comparison is made only on the energy supply and exergy supply, the results of exergy analysis are the same as those of energy analysis. The main difference appears, if the whole chain of supply and demand is taken into consideration. Exergy calculations enable us to analyze how much exergy is consumed in which part, from boiler to building envelope. They also reveal how much energy is supplied for the purpose of heating. Results show that insulation has much bigger effect than effect of boiler efficiency. However, the most effective solution is to improve building envelope together with boiler efficiency. Better thermal insulation also makes an important contribution to the improvement of thermal comfort conditions. It causes higher surface temperatures resulting in a larger warm radiant exergy emission rate and consequently better thermal comfort.

Moisture effect on thermal conductivity of some major elements of a typical Libyan house envelope

International Nuclear Information System (INIS)

Suleiman, Bashir M

2006-01-01

The thermal conductivity and the assessment of moisture effect on building materials are essential for the calculation of the thermal loads on houses. Building materials such as simple units e.g. bricks, tiles, cement plasters, mortar and ground soils are investigated in this work. In the eastern coastal province of Libya, old buildings have thick walls (more than 50 cm thick made of mixed clay and stones) and consequently have good capacitive insulation. On the other hand, the relatively new houses have thin walls and need the addition of insulating materials. Unfortunately, these new houses were constructed without having enough technical data on the thermal properties of building materials and thermal loads were not considered. This leads to uncomfortable living conditions during hot and humid summers and cold and wet winters. This article reports the thermal conductivity values of three types of locally produced building materials used in the construction of a typical Libyan house envelope and gives suggestions to improve the thermal performance of such envelopes. The transient plane source technique (TPS) is used to measure the thermal conductivity of these materials at an average room temperature of 25 deg. C. The TPS technique uses a resistive heater pattern (TPS element) that is cut from a thin sheet of metal and covered on both sides with thin layers of an insulating material. The TPS element/sensor is used both as a heat source and as a temperature sensor. This technique has the dual advantage of short measuring time and low temperature rise (around 1 K) across the sample. This will prevent a non-uniform moisture distribution that may arise when the temperature difference across the wet samples is maintained for a long time. In addition, the flat thin shape of the TPS element substantially reduces the contact resistance between the sample and the sensor. More details about the TPS technique are included

Featured Image: Orbiting Stars Share an Envelope

Science.gov (United States)

Kohler, Susanna

2016-03-01

This beautiful series of snapshots from a simulation (click for a better look!) shows what happens when two stars in a binary system become enclosed in the same stellar envelope. In this binary system, one of the stars has exhausted its hydrogen fuel and become a red giant, complete with an expanding stellar envelope composed of hydrogen and helium. Eventually, the envelope expands so much that the companion star falls into it, where it releases gravitational potential energy into the common envelope. A team led by Sebastian Ohlmann (Heidelberg Institute for Theoretical Studies and University of Wrzburg) recently performed hydrodynamic simulations of this process. Ohlmann and collaborators discovered that the energy release eventually triggers large-scale flow instabilities, which leads to turbulence within the envelope. This process has important consequences for how these systems next evolve (for instance, determining whether or not a supernova occurs!). You can check out the authors video of their simulated stellar inspiral below, or see their paper for more images and results from their study.CitationSebastian T. Ohlmann et al 2016 ApJ 816 L9. doi:10.3847/2041-8205/816/1/L9

Mechanism of protein import across the chloroplast envelope.

Science.gov (United States)

Chen, K; Chen, X; Schnell, D J

2000-01-01

The development and maintenance of chloroplasts relies on the contribution of protein subunits from both plastid and nuclear genomes. Most chloroplast proteins are encoded by nuclear genes and are post-translationally imported into the organelle across the double membrane of the chloroplast envelope. Protein import into the chloroplast consists of two essential elements: the specific recognition of the targeting signals (transit sequences) of cytoplasmic preproteins by receptors at the outer envelope membrane and the subsequent translocation of preproteins simultaneously across the double membrane of the envelope. These processes are mediated via the co-ordinate action of protein translocon complexes in the outer (Toc apparatus) and inner (Tic apparatus) envelope membranes.

Definition and means of maintaining the emergency notification and evacuation system portion of the Plutonium Finishing Plant safety envelope

International Nuclear Information System (INIS)

White, W.F.

1997-01-01

The Emergency Evacuation and Notification System provides information to the PFP Building Emergency Director to assist in determining appropriate emergency response, notifies personnel of the required response, and assists in their response. The report identifies the equipment in the Safety Envelope (SE) for this System and the Administrative, Maintenance, and Surveillance Procedures used to maintain the SE Equipment

Implementation of an Improved Safe Operating Envelope

International Nuclear Information System (INIS)

Prime, Robyn; McIntyre, Mark; Reeves, David

2008-01-01

This paper is a continuation of the paper presented at IYNC 2004 on 'The Definition of a Safe Operating Envelope'. The current paper concentrates on the implementation process of the Safe Operating Envelope employed at the Point Lepreau Generating Station. (authors)

Envelope enhancement increases cortical sensitivity to interaural envelope delays with acoustic and electric hearing.

Directory of Open Access Journals (Sweden)

Douglas E H Hartley

Full Text Available Evidence from human psychophysical and animal electrophysiological studies suggests that sensitivity to interaural time delay (ITD in the modulating envelope of a high-frequency carrier can be enhanced using half-wave rectified stimuli. Recent evidence has shown potential benefits of equivalent electrical stimuli to deaf individuals with bilateral cochlear implants (CIs. In the current study we assessed the effects of envelope shape on ITD sensitivity in the primary auditory cortex of normal-hearing ferrets, and profoundly-deaf animals with bilateral CIs. In normal-hearing animals, cortical sensitivity to ITDs (±1 ms in 0.1-ms steps was assessed in response to dichotically-presented i sinusoidal amplitude-modulated (SAM and ii half-wave rectified (HWR tones (100-ms duration; 70 dB SPL presented at the best-frequency of the unit over a range of modulation frequencies. In separate experiments, adult ferrets were deafened with neomycin administration and bilaterally-implanted with intra-cochlear electrode arrays. Electrically-evoked auditory brainstem responses (EABRs were recorded in response to bipolar electrical stimulation of the apical pair of electrodes with singe biphasic current pulses (40 µs per phase over a range of current levels to measure hearing thresholds. Subsequently, we recorded cortical sensitivity to ITDs (±800 µs in 80-µs steps within the envelope of SAM and HWR biphasic-pulse trains (40 µs per phase; 6000 pulses per second, 100-ms duration over a range of modulation frequencies. In normal-hearing animals, nearly a third of cortical neurons were sensitive to envelope-ITDs in response to SAM tones. In deaf animals with bilateral CI, the proportion of ITD-sensitive cortical neurons was approximately a fifth in response to SAM pulse trains. In normal-hearing and deaf animals with bilateral CI the proportion of ITD sensitive units and neural sensitivity to ITDs increased in response to HWR, compared with SAM stimuli

Synergic effects of thermal mass and natural ventilation on the thermal behaviour of traditional massive buildings

Science.gov (United States)

Gagliano, A.; Nocera, F.; Patania, F.; Moschella, A.; Detommaso, M.; Evola, G.

2016-05-01

The energy policies about energy efficiency in buildings currently focus on new buildings and on existing buildings in case of energy retrofit. However, historic and heritage buildings, that are the trademark of numerous European cities, should also deserve attention; nevertheless, their energy efficiency is nowadays not deeply investigated. In this context, this study evaluates the thermal performance of a traditional massive building situated in a Mediterranean city. Dynamic numerical simulations were carried out on a yearly basis through the software DesignBuilder, both in free-running conditions and in the presence of an air-conditioning (AC) system. The results highlight that the massive envelope of traditional residential buildings helps in maintaining small fluctuations of the indoor temperature, thus limiting the need for AC in the mid-season and in summer. This feature is highly emphasised by exploiting natural ventilation at night, which allows reducing the building energy demand for cooling by about 30%.The research also indicates that, for Mediterranean climate, the increase in thermal insulation does not always induce positive effects on the thermal performance in summer, and that it might even produce an increase in the heat loads due to the transmission through the envelope.

Safe operating envelope

Energy Technology Data Exchange (ETDEWEB)

Oliva, N [Ontario Hydro, Toronto, ON (Canada)

1997-12-01

Safe Operating Envelope is described representing: The outer bound of plant conditions within which day-to-day plant operation must be maintained in order to comply with regulatory requirements, associated safety design criteria and corporate nuclear safety goals. Figs.

Safe operating envelope

International Nuclear Information System (INIS)

Oliva, N.

1997-01-01

Safe Operating Envelope is described representing: The outer bound of plant conditions within which day-to-day plant operation must be maintained in order to comply with regulatory requirements, associated safety design criteria and corporate nuclear safety goals. Figs

Safeguards Envelope Progress FY08

Energy Technology Data Exchange (ETDEWEB)

Robert Bean; Richard Metcalf; Aaron Bevill

2008-09-01

The Safeguards Envelope Project met its milestones by creating a rudimentary safeguards envelope, proving the value of the approach on a small scale, and determining the most appropriate path forward. The Idaho Chemical Processing Plant’s large cache of reprocessing process monitoring data, dubbed UBER Data, was recovered and used in the analysis. A probabilistic Z test was used on a Markov Monte Carlo simulation of expected diversion data when compared with normal operating data. The data regarding a fully transient event in a tank was used to create a simple requirement, representative of a safeguards envelope, whose impact was a decrease in operating efficiency by 1.3% but an increase in material balance period of 26%. This approach is operator, state, and international safeguards friendly and should be applied to future reprocessing plants. Future requirements include tank-to-tank correlations in reprocessing facilities, detailed operations impact studies, simulation inclusion, automated optimization, advanced statistics analysis, and multi-attribute utility analysis.

Safeguards Envelope Progress FY08

International Nuclear Information System (INIS)

Bean, Robert; Metcalf, Richard; Bevill, Aaron

2008-01-01

The Safeguards Envelope Project met its milestones by creating a rudimentary safeguards envelope, proving the value of the approach on a small scale, and determining the most appropriate path forward. The Idaho Chemical Processing Plant's large cache of reprocessing process monitoring data, dubbed UBER Data, was recovered and used in the analysis. A probabilistic Z test was used on a Markov Monte Carlo simulation of expected diversion data when compared with normal operating data. The data regarding a fully transient event in a tank was used to create a simple requirement, representative of a safeguards envelope, whose impact was a decrease in operating efficiency by 1.3% but an increase in material balance period of 26%. This approach is operator, state, and international safeguards friendly and should be applied to future reprocessing plants. Future requirements include tank-to-tank correlations in reprocessing facilities, detailed operations impact studies, simulation inclusion, automated optimization, advanced statistics analysis, and multi-attribute utility analysis

Physical properties of the red giant envelopes

Energy Technology Data Exchange (ETDEWEB)

Maciel, W J [Instituto de Astronomia e Geofisico da Universidade de Sao Paulo (Brazil)

1978-12-01

In this work, several model envelopes are calculated for cool giant stars with mass loss due to the action of stellar radiation pressure on molecules and grains. Molecular profiles as well as average values of some physical parameters of the envelopes are obtained.

Implementation of an Improved Safe Operating Envelope

Energy Technology Data Exchange (ETDEWEB)

Prime, Robyn; McIntyre, Mark [NB Power Nuclear, P.O. Box 600, Lepreau, NB (Canada); Reeves, David [Atlantic Nuclear Services Ltd., PO Box 1268 Fredericton, NB (Canada)

2008-07-01

This paper is a continuation of the paper presented at IYNC 2004 on 'The Definition of a Safe Operating Envelope'. The current paper concentrates on the implementation process of the Safe Operating Envelope employed at the Point Lepreau Generating Station. (authors)

Competitive landscape of the EU’s insulation materials industry for energy-efficient buildings

OpenAIRE

PAVEL CLAUDIU; BLAGOEVA DARINA

2017-01-01

Insulation materials could contribute significantly to improving the overall energy efficiency and sustainability of the buildings, especially by reducing the energy losses through the building envelope (walls, roofs, floors, etc.). The global demand for thermal insulation materials in building applications is projected to increase at a CAGR of 4.5 % between 2016 and 2027. In the EU the demand for thermal insulation materials is estimated at 3.48 % (2015-2027). Wool minerals (glass and stone ...

Use of response envelopes for seismic margin assessment of reinforced concrete walls and slabs

Energy Technology Data Exchange (ETDEWEB)

Ile, Nicolas; Frau, Alberto, E-mail: alberto.frau@cea.fr

2017-04-01

Highlights: • Proposal of a method for application of the elliptical envelope to RC shell elements. • Proposal of new algorithms for the seismic margin evaluation for RC shell elements. • Verification of a RC wall 3D structure, using the proposed assessment approach. - Abstract: Seismic safety evaluations of existing nuclear facilities are usually based on the assumption of structural linearity. For the design basis earthquake (DBE), it is reasonable to apply a conventional evaluation of the seismic safety of building structures and carry out a linear elastic analysis to assess the load effects on structural elements. Estimating the seismic capacity of a structural element requires an estimation of the critical combination of responses acting in this structural element and compare this combination with the capacity of the element. By exploiting the response-spectrum-based procedure for predicting the response envelopes in linear structures formulated by Menun and Der Kiureghian (2000a), algorithms are developed for the seismic margin assessment of reinforced concrete shell finite elements. These algorithms facilitate the comparison of the response-spectrum-based envelopes to prescribed capacity surfaces for the purpose of assessing the safety margin of this kind of structures. The practical application of elliptical response envelopes in case of shell finite elements is based on the use of layer models such as those developed by Marti (1990), which transfer the generalized stress field to three layers under the assumption that the two outer layers carry membrane forces and the internal layer carries only the out-of-plane shears. The utility of the assessment approach is discussed with reference to a case study of a 3D structure made of reinforced concrete walls.

Use of response envelopes for seismic margin assessment of reinforced concrete walls and slabs

International Nuclear Information System (INIS)

Ile, Nicolas; Frau, Alberto

2017-01-01

Highlights: • Proposal of a method for application of the elliptical envelope to RC shell elements. • Proposal of new algorithms for the seismic margin evaluation for RC shell elements. • Verification of a RC wall 3D structure, using the proposed assessment approach. - Abstract: Seismic safety evaluations of existing nuclear facilities are usually based on the assumption of structural linearity. For the design basis earthquake (DBE), it is reasonable to apply a conventional evaluation of the seismic safety of building structures and carry out a linear elastic analysis to assess the load effects on structural elements. Estimating the seismic capacity of a structural element requires an estimation of the critical combination of responses acting in this structural element and compare this combination with the capacity of the element. By exploiting the response-spectrum-based procedure for predicting the response envelopes in linear structures formulated by Menun and Der Kiureghian (2000a), algorithms are developed for the seismic margin assessment of reinforced concrete shell finite elements. These algorithms facilitate the comparison of the response-spectrum-based envelopes to prescribed capacity surfaces for the purpose of assessing the safety margin of this kind of structures. The practical application of elliptical response envelopes in case of shell finite elements is based on the use of layer models such as those developed by Marti (1990), which transfer the generalized stress field to three layers under the assumption that the two outer layers carry membrane forces and the internal layer carries only the out-of-plane shears. The utility of the assessment approach is discussed with reference to a case study of a 3D structure made of reinforced concrete walls.

Numerical analysis of the influence of thermal mass, phase change materials and furniture / indoor content on building energy flexibility (long abstract)

DEFF Research Database (Denmark)

Johra, Hicham

investigating the influence of the different types of thermal inertia on buildings energy flexibility. Although the insulation level and thermal mass of a building envelope are the dominant parameters, it appears that indoor content cannot be neglected for lightweight structure building simulations. Finally...

Physical properties of the red giant envelopes

International Nuclear Information System (INIS)

Maciel, W.J.

1978-01-01

In this work, several model envelopes are calculated for cool giant stars with mass loss due to the action of stellar radiation pressure on molecules and grains. Molecular profiles as well as average values of some physical parameters of the envelopes are obtained [pt

Climate-Specific Passive Building Standards

Energy Technology Data Exchange (ETDEWEB)

Wright, Graham S. [Building Science Corp., Westford, MA (United States); Klingenberg, Katrin [Building Science Corp., Westford, MA (United States)

2015-07-29

In 2012, the U.S. Department of Energy (DOE) recognized the value of performance-based passive building standards when it joined with Passive House Institute US (PHIUS) to promote DOE’s Challenge Home program in tandem with the PHIUS+ Certification program. Since then, the number of passive building projects that have been certified under the partnership has grown exponentially because of some synergy. Passive building represents a well-developed approach to arrive at the envelope basis for zero energy and energy-positive projects by employing performance-based criteria and maximizing cost-effective savings from conservation before implementing renewable energy technologies. The Challenge Home program evolved into the Zero Energy Ready Home (ZERH) program in a move toward 1) attaining zero energy and 2) including active renewable energy generation such as photovoltaics (PV)—toward the zero energy goal.

Full waveform inversion using envelope-based global correlation norm

Science.gov (United States)

Oh, Ju-Won; Alkhalifah, Tariq

2018-05-01

To increase the feasibility of full waveform inversion on real data, we suggest a new objective function, which is defined as the global correlation of the envelopes of modelled and observed data. The envelope-based global correlation norm has the advantage of the envelope inversion that generates artificial low-frequency information, which provides the possibility to recover long-wavelength structure in an early stage. In addition, the envelope-based global correlation norm maintains the advantage of the global correlation norm, which reduces the sensitivity of the misfit to amplitude errors so that the performance of inversion on real data can be enhanced when the exact source wavelet is not available and more complex physics are ignored. Through the synthetic example for 2-D SEG/EAGE overthrust model with inaccurate source wavelet, we compare the performance of four different approaches, which are the least-squares waveform inversion, least-squares envelope inversion, global correlation norm and envelope-based global correlation norm. Finally, we apply the envelope-based global correlation norm on the 3-D Ocean Bottom Cable (OBC) data from the North Sea. The envelope-based global correlation norm captures the strong reflections from the high-velocity caprock and generates artificial low-frequency reflection energy that helps us recover long-wavelength structure of the model domain in the early stages. From this long-wavelength model, the conventional global correlation norm is sequentially applied to invert for higher-resolution features of the model.

Inhibition of enveloped viruses infectivity by curcumin.

Directory of Open Access Journals (Sweden)

Tzu-Yen Chen

Full Text Available Curcumin, a natural compound and ingredient in curry, has antiinflammatory, antioxidant, and anticarcinogenic properties. Previously, we reported that curcumin abrogated influenza virus infectivity by inhibiting hemagglutination (HA activity. This study demonstrates a novel mechanism by which curcumin inhibits the infectivity of enveloped viruses. In all analyzed enveloped viruses, including the influenza virus, curcumin inhibited plaque formation. In contrast, the nonenveloped enterovirus 71 remained unaffected by curcumin treatment. We evaluated the effects of curcumin on the membrane structure using fluorescent dye (sulforhodamine B; SRB-containing liposomes that mimic the viral envelope. Curcumin treatment induced the leakage of SRB from these liposomes and the addition of the influenza virus reduced the leakage, indicating that curcumin disrupts the integrity of the membranes of viral envelopes and of liposomes. When testing liposomes of various diameters, we detected higher levels of SRB leakage from the smaller-sized liposomes than from the larger liposomes. Interestingly, the curcumin concentration required to reduce plaque formation was lower for the influenza virus (approximately 100 nm in diameter than for the pseudorabies virus (approximately 180 nm and the vaccinia virus (roughly 335 × 200 × 200 nm. These data provide insights on the molecular antiviral mechanisms of curcumin and its potential use as an antiviral agent for enveloped viruses.

Inhibition of Enveloped Viruses Infectivity by Curcumin

Science.gov (United States)

Wen, Hsiao-Wei; Ou, Jun-Lin; Chiou, Shyan-Song; Chen, Jo-Mei; Wong, Min-Liang; Hsu, Wei-Li

2013-01-01

Curcumin, a natural compound and ingredient in curry, has antiinflammatory, antioxidant, and anticarcinogenic properties. Previously, we reported that curcumin abrogated influenza virus infectivity by inhibiting hemagglutination (HA) activity. This study demonstrates a novel mechanism by which curcumin inhibits the infectivity of enveloped viruses. In all analyzed enveloped viruses, including the influenza virus, curcumin inhibited plaque formation. In contrast, the nonenveloped enterovirus 71 remained unaffected by curcumin treatment. We evaluated the effects of curcumin on the membrane structure using fluorescent dye (sulforhodamine B; SRB)-containing liposomes that mimic the viral envelope. Curcumin treatment induced the leakage of SRB from these liposomes and the addition of the influenza virus reduced the leakage, indicating that curcumin disrupts the integrity of the membranes of viral envelopes and of liposomes. When testing liposomes of various diameters, we detected higher levels of SRB leakage from the smaller-sized liposomes than from the larger liposomes. Interestingly, the curcumin concentration required to reduce plaque formation was lower for the influenza virus (approximately 100 nm in diameter) than for the pseudorabies virus (approximately 180 nm) and the vaccinia virus (roughly 335 × 200 × 200 nm). These data provide insights on the molecular antiviral mechanisms of curcumin and its potential use as an antiviral agent for enveloped viruses. PMID:23658730

Contrasting the capabilities of building energy performance simulation programs

Energy Technology Data Exchange (ETDEWEB)

Crawley, Drury B. [US Department of Energy, Washington, DC (United States); Hand, Jon W. [University of Strathclyde, Glasgow, Scotland (United Kingdom). Energy Systems Research Unit; Kummert, Michael [University of Wisconsin-Madison (United States). Solar Energy Laboratory; Griffith, Brent T. [National Renewable Energy Laboratory, Golden, CO (United States)

2008-04-15

For the past 50 years, a wide variety of building energy simulation programs have been developed, enhanced and are in use throughout the building energy community. This paper is an overview of a report, which provides up-to-date comparison of the features and capabilities of twenty major building energy simulation programs. The comparison is based on information provided by the program developers in the following categories: general modeling features; zone loads; building envelope and daylighting and solar; infiltration, ventilation and multizone airflow; renewable energy systems; electrical systems and equipment; HVAC systems; HVAC equipment; environmental emissions; economic evaluation; climate data availability, results reporting; validation; and user interface, links to other programs, and availability. (author)

Performance demonstration and evaluation of the synergetic application of vanadium dioxide glazing and phase change material in passive buildings

International Nuclear Information System (INIS)

Long, Linshuang; Ye, Hong; Gao, Yanfeng; Zou, Ruqiang

2014-01-01

Highlights: • VO 2 and PCM were combined in passive building application for the first time. • Synergetic performance of them is demonstrated in a full size room. • Synergetic application has a better performance than the solo ones. • The materials interact with each other in synergetic application. • ESI can be used to evaluate the performance of the synergetic application. - Abstract: One of the key methods to improve the energy saving performance of a building is to apply advanced materials or components to the building envelope. However, the two parts of a building’s envelope, the transparent one and the non-transparent one, are usually investigated individually by existing literature. In this study, vanadium dioxide (VO 2 ) glazing, an advanced energy-efficient element applied to the transparent parts of the building envelope, and phase change material (PCM), a typical thermal storage material used to improve the non-transparent parts of the building envelope, were adopted simultaneously for the first time. The synergetic performance of VO 2 glazing and PCM, demonstrated in a full-scale, lightweight, passive room, resulted in a significant improvement in the thermal comfort degree. The Energy Saving Index (ESI) is a simple and effective indicator that can be used to evaluate the passive application performance of a single energy-efficient material or component on a common standpoint. In this work, the index was broadened to evaluate the performance of more than one material, showing that ESI is feasible and favorable to analyze the coefficient application of several building materials and/or components. Using the ESI, the performance of the synergetic application was also compared with those of the sole materials, indicating that the synergetic application has a better performance during the cooling period. Furthermore the synergetic application involves an interplay rather than a simple combination of the energy-efficient materials. The

A Spectral Algorithm for Envelope Reduction of Sparse Matrices

Science.gov (United States)

Barnard, Stephen T.; Pothen, Alex; Simon, Horst D.

1993-01-01

The problem of reordering a sparse symmetric matrix to reduce its envelope size is considered. A new spectral algorithm for computing an envelope-reducing reordering is obtained by associating a Laplacian matrix with the given matrix and then sorting the components of a specified eigenvector of the Laplacian. This Laplacian eigenvector solves a continuous relaxation of a discrete problem related to envelope minimization called the minimum 2-sum problem. The permutation vector computed by the spectral algorithm is a closest permutation vector to the specified Laplacian eigenvector. Numerical results show that the new reordering algorithm usually computes smaller envelope sizes than those obtained from the current standard algorithms such as Gibbs-Poole-Stockmeyer (GPS) or SPARSPAK reverse Cuthill-McKee (RCM), in some cases reducing the envelope by more than a factor of two.

Application of Surrogate Models for Building Envelope Design Exploration and Optimization

NARCIS (Netherlands)

Yang, D.; Šileryte, R.; D'Aquilio, A.; Turrin, M.; Attar, Ramtin; Chronis, Angelos; Hanna, Sean; Turrin, Michela

2016-01-01

Building performance simulations are usually timeconsuming. They may account for the major portion of time spent in Computational Design Optimization (CDO), for instance, annual hourly daylight and energy simulations. In this case, the optimization may become less efficient or even infeasible within

Definition and means of maintaining the emergency notification and evacuation system portion of the plutonium finishing plant safety envelope

International Nuclear Information System (INIS)

WHITE, W.F.

1999-01-01

The Emergency Evacuation and Notification System provides information to the Plutonium Finishing Plant (PFP) Building Emergency Director to assist in determining appropriate emergency response, notifies personnel of the required response, and assists in their response. The report identifies the equipment in the Safety Envelope (SE) for this System and the Administrative, Maintenance, and Surveillance Procedures used to maintain the SE Equipment

Common envelope evolution

NARCIS (Netherlands)

Taam, Ronald E.; Ricker, Paul M.

2010-01-01

The common envelope phase of binary star evolution plays a central role in many evolutionary pathways leading to the formation of compact objects in short period systems. Using three dimensional hydrodynamical computations, we review the major features of this evolutionary phase, focusing on the

Numerical Analysis of the Impact of Thermal Inertia from the Furniture / Indoor Content and Phase Change Materials on the Building Energy Flexibility

DEFF Research Database (Denmark)

Johra, Hicham; Heiselberg, Per Kvols; Le Dréau, Jérôme

investigating the influence of the different types of thermal inertia on buildings energy flexibility. Although the insulation level and thermal mass of a building envelope are the dominant parameters, it appears that indoor content cannot be neglected for lightweight structure building simulations. Finally...

Multiscale modelling for better hygrothermal prediction of porous building materials

Directory of Open Access Journals (Sweden)

Belarbi Rafik

2018-01-01

Full Text Available The aim of this work is to understand the influence of the microstructuralgeometric parameters of porous building materials on the mechanisms of coupled heat, air and moisture transfers, in order to predict behavior of the building to control and improve it in its durability. For this a multi-scale approach is implemented. It consists of mastering the dominant physical phenomena and their interactions on the microscopic scale. Followed by a dual-scale modelling, microscopic-macroscopic, of coupled heat, air and moisture transfers that takes into account the intrinsic properties and microstructural topology of the material using X-ray tomography combined with the correlation of 3D images were undertaken. In fact, the hygromorphicbehavior under hydric solicitations was considered. In this context, a model of coupled heat, air and moisture transfer in porous building materials was developed using the periodic homogenization technique. These informations were subsequently implemented in a dynamic computation simulation that model the hygrothermalbehaviourof material at the scale of the envelopes and indoor air quality of building. Results reveals that is essential to consider the local behaviors of materials, but also to be able to measure and quantify the evolution of its properties on a macroscopic scale from the youngest age of the material. In addition, comparisons between experimental and numerical temperature and relative humidity profilesin multilayers wall and in building envelopes were undertaken. Good agreements were observed.

MHTGR thermal performance envelopes: Reliability by design

International Nuclear Information System (INIS)

Etzel, K.T.; Howard, W.W.; Zgliczynski, J.B.

1992-05-01

This document discusses thermal performance envelopes which are used to specify steady-state design requirements for the systems of the Modular High Temperature Gas-Cooled Reactor to maximize plant performance reliability with optimized design. The thermal performance envelopes are constructed around the expected operating point accounting for uncertainties in actual plant as-built parameters and plant operation. The components are then designed to perform successfully at all points within the envelope. As a result, plant reliability is maximized by accounting for component thermal performance variation in the design. The design is optimized by providing a means to determine required margins in a disciplined and visible fashion

The limited role of recombination energy in common envelope removal

Science.gov (United States)

Grichener, Aldana; Sabach, Efrat; Soker, Noam

2018-05-01

We calculate the outward energy transport time by convection and photon diffusion in an inflated common envelope and find this time to be shorter than the envelope expansion time. We conclude therefore that most of the hydrogen recombination energy ends in radiation rather than in kinetic energy of the outflowing envelope. We use the stellar evolution code MESA and inject energy inside the envelope of an asymptotic giant branch star to mimic energy deposition by a spiraling-in stellar companion. During 1.7 years the envelope expands by a factor of more than 2. Along the entire evolution the convection can carry the energy very efficiently outwards, to the radius where radiative transfer becomes more efficient. The total energy transport time stays within several months, shorter than the dynamical time of the envelope. Had we included rapid mass loss, as is expected in the common envelope evolution, the energy transport time would have been even shorter. It seems that calculations that assume that most of the recombination energy ends in the outflowing gas might be inaccurate.

ENERGY EFFICIENT BUILDINGS PROGRAM. CHAPTER FROM THE ENERGY AND ENVIRONMENT DIVISION ANNUAL REPORT 1979

Energy Technology Data Exchange (ETDEWEB)

Authors, Various

1979-12-01

The research reported in this volume was undertaken during FY 1979 within the Energy & Environment Division of the Lawrence Berkeley Laboratory. This volume will comprise a section of the Energy & Environment Division 1979 Annual Report, to be published in the summer of 1980. Work reported relate to: thermal performance of building envelopes; building ventilation and indoor air quality; a computer program for predicting energy use in buildings; study focused specifically on inherently energy intensive hospital buildings; energy efficient windows and lighting; potential for energy conservation and savings in the buildings sector; and evaluation of energy performance standards for residential buildings.

Vision-based building energy diagnostics and retrofit analysis using 3D thermography and building information modeling

Science.gov (United States)

Ham, Youngjib

The emerging energy crisis in the building sector and the legislative measures on improving energy efficiency are steering the construction industry towards adopting new energy efficient design concepts and construction methods that decrease the overall energy loads. However, the problems of energy efficiency are not only limited to the design and construction of new buildings. Today, a significant amount of input energy in existing buildings is still being wasted during the operational phase. One primary source of the energy waste is attributed to unnecessary heat flows through building envelopes during hot and cold seasons. This inefficiency increases the operational frequency of heating and cooling systems to keep the desired thermal comfort of building occupants, and ultimately results in excessive energy use. Improving thermal performance of building envelopes can reduce the energy consumption required for space conditioning and in turn provide building occupants with an optimal thermal comfort at a lower energy cost. In this sense, energy diagnostics and retrofit analysis for existing building envelopes are key enablers for improving energy efficiency. Since proper retrofit decisions of existing buildings directly translate into energy cost saving in the future, building practitioners are increasingly interested in methods for reliable identification of potential performance problems so that they can take timely corrective actions. However, sensing what and where energy problems are emerging or are likely to emerge and then analyzing how the problems influence the energy consumption are not trivial tasks. The overarching goal of this dissertation focuses on understanding the gaps in knowledge in methods for building energy diagnostics and retrofit analysis, and filling these gaps by devising a new method for multi-modal visual sensing and analytics using thermography and Building Information Modeling (BIM). First, to address the challenges in scaling and

Correlations in hydrothermal properties of building insulation

International Nuclear Information System (INIS)

Antonyová, A

2013-01-01

The contribution comprises analysis that is based on scientific work as a part of participation on the international research project carried out at the University of Prešov in Prešov and Vienna University of Technology entitled 'Detection and Management of Risk Processes in Building Insulation' and numbered SRDA SK-AT-0008-10. Statistical approach with correlations among humidity, time and temperature values in the space between the wall and building insulation uses the set of data obtained during the measurement series as testing using a new technology with equipment that does not influence the environment properties in the space. Therefore such real mapping can bring a real picture of possible condensation as a risk process in the building envelope.

Indoor radon problem in energy efficient multi-storey buildings.

Science.gov (United States)

Yarmoshenko, I V; Vasilyev, A V; Onishchenko, A D; Kiselev, S M; Zhukovsky, M V

2014-07-01

Modern energy-efficient architectural solutions and building construction technologies such as monolithic concrete structures in combination with effective insulation reduce air permeability of building envelope. As a result, air exchange rate is significantly reduced and conditions for increased radon accumulation in indoor air are created. Based on radon survey in Ekaterinburg, Russia, remarkable increase in indoor radon concentration level in energy-efficient multi-storey buildings was found in comparison with similar buildings constructed before the-energy-saving era. To investigate the problem of indoor radon in energy-efficient multi-storey buildings, the measurements of radon concentration have been performed in seven modern buildings using radon monitoring method. Values of air exchange rate and other parameters of indoor climate in energy-efficient buildings have been estimated. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Green building challenge 2002 in Canada : an overview

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-02-01

The Green Building Challenge (GBC) in Canada was launched to help the building community meet environmental challenges and improve the environmental performance of buildings. Tools have been made available to the building industry to make informed environmental choices during the conception design stage of a project. The tools help architects, researchers and policy analysts in choosing material mixes and other design options that will minimize a building's potential life cycle environmental impacts and promote sustainable development. Green buildings involve the complete structure and envelope, including cladding, insulation, gypsum wall board, roofing and windows. The type of building and its location is also considered. Long term sustainability also considers energy use and emissions related to a building's energy system. This presentation described the following 3 projects which were selected for assessment in the GBC-2002: (1) the Mayo School in Mayo, Yukon Territory, (2) the Jackson-Triggs Winery in Niagara-on-the-Lake, Ontario, and (3) the Red River College in Winnipeg, Manitoba. The GBC-2002 Canadian Team nominated them as the best buildings being designed in Canada.10 figs.

The impact of thermal bridges on the energy demand of buildings with double brick wall constructions

Energy Technology Data Exchange (ETDEWEB)

Theodosiou, T.G. [Department of Engineering and Management of Energy Resources, University of Western Macedonia, GR-50100 Kozani (Greece); Papadopoulos, A.M. [Laboratory of Heat Transfer and Environmental Engineering, Department of Mechanical Engineering, Aristotle University Thessaloniki, GR-54124 Thessaloniki (Greece)

2008-07-01

The implementation of the European Directive on the Energy Performance of Buildings (EPBD) is a milestone towards the improvement of energy efficiency in the building sector. However, even in cases where impressive measures can be implemented in the densely built urban environment, the less glamorous measure of building's envelope thermal insulation remains a prerequisite towards the improvement of the building's energy efficiency. Despite the insulation requirements specified by national regulations, thermal bridges in the building's envelope remain a weak spot in the constructions. Moreover, in many countries construction practices tend to implement only partially the insulation measures foreseen by regulations. As a result, thermal losses are in practice greater than those predicted during the design stage. This paper presents a study on representative wall thermal insulation configurations used in Greek buildings, in order to investigate the impact of the thermal bridges on the energy consumption. The double wall construction, used widely in Greece and not only there, is rather susceptible to the occurrence of thermal bridges, in contrast to a typical thermal insulating facade, like the one applied in Central Europe. The analysis of the thermal bridges' impact will in that sense also highlight the potential for energy renovation measures in older buildings. (author)

Analysis of the Dependence between Energy Demand Indicators in Buildings Based on Variants for Improving Energy Efficiency in a School Building

Science.gov (United States)

Skiba, Marta; Rzeszowska, Natalia

2017-09-01

One of the five far-reaching goals of the European Union is climate change and sustainable energy use. The first step in the implementation of this task is to reduce energy demand in buildings to a minimum by 2021, and in the case of public buildings by 2019. This article analyses the possibility of improving energy efficiency in public buildings, the relationship between particular indicators of the demand for usable energy (UE), final energy (FE) and primary energy (PE) in buildings and the impact of these indicators on the assessment of energy efficiency in public buildings, based on 5 variants of extensive thermal renovation of a school building. The analysis of the abovementioned variants confirms that the thermal renovation of merely the outer envelope of the building is insufficient and requires the use of additional energy sources, for example RES. Moreover, each indicator of energy demand in the building plays a key role in assessing the energy efficiency of the building. For this reason it is important to analyze each of them individually, as well as the dependencies between them.

Spectral Envelopes and Additive + Residual Analysis/Synthesis

Science.gov (United States)

Rodet, Xavier; Schwarz, Diemo

The subject of this chapter is the estimation, representation, modification, and use of spectral envelopes in the context of sinusoidal-additive-plus-residual analysis/synthesis. A spectral envelope is an amplitude-vs-frequency function, which may be obtained from the envelope of a short-time spectrum (Rodet et al., 1987; Schwarz, 1998). [Precise definitions of such an envelope and short-time spectrum (STS) are given in Section 2.] The additive-plus-residual analysis/synthesis method is based on a representation of signals in terms of a sum of time-varying sinusoids and of a non-sinusoidal residual signal [e.g., see Serra (1989), Laroche et al. (1993), McAulay and Quatieri (1995), and Ding and Qian (1997)]. Many musical sound signals may be described as a combination of a nearly periodic waveform and colored noise. The nearly periodic part of the signal can be viewed as a sum of sinusoidal components, called partials, with time-varying frequency and amplitude. Such sinusoidal components are easily observed on a spectral analysis display (Fig. 5.1) as obtained, for instance, from a discrete Fourier transform.

Energy performance of building fabric - Comparing two types of vernacular residential houses

Science.gov (United States)

Draganova, Vanya Y.; Matsumoto, Hiroshi; Tsuzuki, Kazuyo

2017-10-01

Notwithstanding apparent differences, Japanese and Bulgarian traditional residential houses share a lot of common features - building materials, building techniques, even layout design. Despite the similarities, these two types of houses have not been compared so far. The study initiates such comparison. The focus is on houses in areas with similar climate in both countries. Current legislation requirements are compared, as well as the criteria for thermal comfort of people. Achieving high energy performance results from a dynamic system of 4 main key factors - thermal comfort range, heating/cooling source, building envelope and climatic conditions. A change in any single one of them can affect the final energy performance. However, it can be expected that a combination of changes in more than one factor usually occurs. The aim of this study is to evaluate the correlation between the thermal performance of building envelope designed under current regulations and a traditional one, having in mind the different thermal comfort range in the two countries. A sample building model is calculated in Scenario 1 - Japanese traditional building fabric, Scenario 2 - Bulgarian traditional building fabric and Scenario 3 - meeting the requirements of the more demanding current regulations. The energy modelling is conducted using EnergyPlus through OpenStudio cross-platform of software tools. The 3D geometry for the simulation is created using OpenStudio SketchUp Plug-in. Equal number of inhabitants, electricity consumption and natural ventilation is assumed. The results show that overall low energy consumption can be achieved using traditional building fabric as well, when paired with a wider thermal comfort range. Under these conditions traditional building design is still viable today. This knowledge can reestablish the use of traditional building fabric in contemporary design, stimulate preservation of local culture, building traditions and community identity.

Thermal mass impact on energy performance of a low, medium and heavy mass building in Belgrade

Directory of Open Access Journals (Sweden)

Anđelković Bojan V.

2012-01-01

Full Text Available Heavy mass materials used in building structures and architecture can significantly affect building energy performance and occupant comfort. The purpose of this study was to investigate if thermal mass can improve the internal environment of a building, resulting in lower energy requirements from the mechanical systems. The study was focused on passive building energy performance and compared annual space heating and cooling energy requirements for an office building in Belgrade with several different applications of thermal mass. A three-dimensional building model was generated to represent a typical office building. Building shape, orientation, glazing to wall ratio, envelope insulation thickness, and indoor design conditions were held constant while location and thickness of building mass (concrete was varied between cases in a series of energy simulations. The results were compared and discussed in terms of the building space heating and cooling energy and demand affected by thermal mass. The simulation results indicated that with addition of thermal mass to the building envelope and structure: 100% of all simulated cases experienced reduced annual space heating energy requirements, 67% of all simulated cases experienced reduced annual space cooling energy requirements, 83% of all simulated cases experienced reduced peak space heating demand and 50% of all simulated cases experienced reduced peak space cooling demand. The study demonstrated that there exists a potential for reducing space heating and cooling energy requirements with heavy mass construction in the analyzed climate region (Belgrade, Serbia.

Definition and means of maintaining the emergency notification and evacuation system portion of the plutonium finishing plant safety envelope; TOPICAL

International Nuclear Information System (INIS)

WHITE, W.F.

1999-01-01

The Emergency Evacuation and Notification System provides information to the Plutonium Finishing Plant (PFP) Building Emergency Director to assist in determining appropriate emergency response, notifies personnel of the required response, and assists in their response. The report identifies the equipment in the Safety Envelope (SE) for this System and the Administrative, Maintenance, and Surveillance Procedures used to maintain the SE Equipment

DATA ENVELOPMENT ANALYSIS OF BANKING SECTOR IN BANGLADESH

Directory of Open Access Journals (Sweden)

Md. Rashedul Hoque

2012-05-01

Full Text Available Banking sector of Bangladesh is flourishing and contributing to its economy. In this aspect measuring efficiency is important. Data Envelopment Analysis technique is used for this purpose. The data are collected from the annual reports of twenty four different banks in Bangladesh. Data Envelopment Analysis is mainly of two types - constant returns to scale and variable returns to scale. Since this study attempts to maximize output, so the output oriented Data Envelopment Analysis is used. The most efficient bank is one that obtains the highest efficiency score.

Energy Savings Modeling and Inspection Guidelines for Commercial Building Federal Tax Deductions for Buildings in 2016 and Later

Energy Technology Data Exchange (ETDEWEB)

Deru, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States); Field-Macumber, Kristin [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-09-01

This document provides guidance for modeling and inspecting energy-efficient property in commercial buildings for certification of the energy and power cost savings related to Section 179D of the Internal Revenue Code (IRC) enacted in Section 1331 of the 2005 Energy Policy Act (EPAct) of 2005, noted in Internal Revenue Service (IRS) Notices 2006-52 (IRS 2006), 2008-40 (IRS 2008) and 2012-26 (IRS 2012), and updated by the Protecting Americans from Tax Hikes (PATH) Act of 2015. Specifically, Section 179D provides federal tax deductions for energy-efficient property related to a commercial building's envelope; interior lighting; heating, ventilating, and air conditioning (HVAC); and service hot water (SHW) systems. This document applies to buildings placed in service on or after January 1, 2016.

Validating predictions from climate envelope models

Science.gov (United States)

Watling, J.; Bucklin, D.; Speroterra, C.; Brandt, L.; Cabal, C.; Romañach, Stephanie S.; Mazzotti, Frank J.

2013-01-01

Climate envelope models are a potentially important conservation tool, but their ability to accurately forecast species’ distributional shifts using independent survey data has not been fully evaluated. We created climate envelope models for 12 species of North American breeding birds previously shown to have experienced poleward range shifts. For each species, we evaluated three different approaches to climate envelope modeling that differed in the way they treated climate-induced range expansion and contraction, using random forests and maximum entropy modeling algorithms. All models were calibrated using occurrence data from 1967–1971 (t1) and evaluated using occurrence data from 1998–2002 (t2). Model sensitivity (the ability to correctly classify species presences) was greater using the maximum entropy algorithm than the random forest algorithm. Although sensitivity did not differ significantly among approaches, for many species, sensitivity was maximized using a hybrid approach that assumed range expansion, but not contraction, in t2. Species for which the hybrid approach resulted in the greatest improvement in sensitivity have been reported from more land cover types than species for which there was little difference in sensitivity between hybrid and dynamic approaches, suggesting that habitat generalists may be buffered somewhat against climate-induced range contractions. Specificity (the ability to correctly classify species absences) was maximized using the random forest algorithm and was lowest using the hybrid approach. Overall, our results suggest cautious optimism for the use of climate envelope models to forecast range shifts, but also underscore the importance of considering non-climate drivers of species range limits. The use of alternative climate envelope models that make different assumptions about range expansion and contraction is a new and potentially useful way to help inform our understanding of climate change effects on species.

Validating predictions from climate envelope models.

Directory of Open Access Journals (Sweden)

James I Watling

Full Text Available Climate envelope models are a potentially important conservation tool, but their ability to accurately forecast species' distributional shifts using independent survey data has not been fully evaluated. We created climate envelope models for 12 species of North American breeding birds previously shown to have experienced poleward range shifts. For each species, we evaluated three different approaches to climate envelope modeling that differed in the way they treated climate-induced range expansion and contraction, using random forests and maximum entropy modeling algorithms. All models were calibrated using occurrence data from 1967-1971 (t1 and evaluated using occurrence data from 1998-2002 (t2. Model sensitivity (the ability to correctly classify species presences was greater using the maximum entropy algorithm than the random forest algorithm. Although sensitivity did not differ significantly among approaches, for many species, sensitivity was maximized using a hybrid approach that assumed range expansion, but not contraction, in t2. Species for which the hybrid approach resulted in the greatest improvement in sensitivity have been reported from more land cover types than species for which there was little difference in sensitivity between hybrid and dynamic approaches, suggesting that habitat generalists may be buffered somewhat against climate-induced range contractions. Specificity (the ability to correctly classify species absences was maximized using the random forest algorithm and was lowest using the hybrid approach. Overall, our results suggest cautious optimism for the use of climate envelope models to forecast range shifts, but also underscore the importance of considering non-climate drivers of species range limits. The use of alternative climate envelope models that make different assumptions about range expansion and contraction is a new and potentially useful way to help inform our understanding of climate change effects on

Foundation helps refurbish buildings

International Nuclear Information System (INIS)

Camenzind, B.

2006-01-01

This article looks at the activities of the Swiss 'Climate-Cent' foundation, which is helping support the energetic refurbishment of building envelopes. The conditions which have to be fulfilled to receive grants are explained. Work supported includes the replacement of windows and the insulation of roofs and attics as well as outside walls. Details on the financial support provided and examples of projects supported are given. The source of the finance needed to provide such support - a voluntary levy on petrol - and further support provided in certain Swiss cantons is commented on

Introduction to Building Systems Performance: Houses That Work II. Revised February 2005

Energy Technology Data Exchange (ETDEWEB)

2005-03-01

Buildings should be suited to their environments. Design and construction must be responsive to varying seismic risks, wind loads, and snow loads, as well as soil conditions, frost depth, orientation, and solar radiation. In addition, building envelopes and mechanical systems should be designed for a specific hygro-thermal regions, rain exposure, and interior climate. The Building Science Consortium (BSC) design recommendations are based on the hygro-thermal regions with reference to the annual rainfall. Local climate must be addressed if it differs significantly from the climate described for a particular design.

Stimulation of good building and ductwork airtightness through EPBD

DEFF Research Database (Denmark)

Guyot, Gaelle; Carrié, Remi; Schild, Peter

Building and ductwork leakage are detrimental to energy conservation, comfort, and hygiene. They can cause building damage and it can prevent proper control of the ventilation airflow rates. Through the ASIEPI project, we have identified that while some key elements for a market transformation on...... on envelope airtightness are under development in many countries, status quo seems to prevail for the duct market. With the objective of all new constructions being “nearly zero energy buildings” in 2020, policy makers need to know how better airtightness can be stimulated....

Delivering COBie data - Focus on curtain walls and building envelopes

DEFF Research Database (Denmark)

Karlshøj, Jan; Borin, P.; Carradori, M.

COBie is a standard data framework whose main purpose is to transmit useful, reliable and us-able information collected throughout the whole building process and to be consumed in order to properly maintain the facility. Focusing on Facility Management information exchanges and considering the UK...... BIM policies and requirements, this paper shows the results obtained applying COBie to complex products such as curtain walls. Two Information Delivery Manuals (IDMs) were also developed, in order to provide a com-monly known and standardized framework, which can regulate the COBie-based information...

Economical evaluation of damaged vacuum insulation panels in buildings

Science.gov (United States)

Kim, Y. M.; Lee, H. Y.; Choi, G. S.; Kang, J. S.

2015-12-01

In Korea, thermal insulation standard of buildings have been tightened annually to satisfy the passive house standard from the year 2009. The current domestic policies about disseminating green buildings are progressively conducted. All buildings should be the zero energy building in the year 2025, obligatorily. The method is applied to one of the key technologies for high-performance insulation for zero energy building. The vacuum insulation panel is an excellent high performance insulation. But thermal performance of damaged vacuum insulation panels is reduced significantly. In this paper, the thermal performance of damaged vacuum insulation panels was compared and analyzed. The measurement result of thermal performance depends on the core material type. The insulation of building envelope is usually selected by economic feasibility. To evaluate the economic feasibility of VIPs, the operation cost was analyzed by simulation according to the types and damaged ratio of VIPs

Rapid Process to Generate Beam Envelopes for Optical System Analysis

Science.gov (United States)

Howard, Joseph; Seals, Lenward

2012-01-01

The task of evaluating obstructions in the optical throughput of an optical system requires the use of two disciplines, and hence, two models: optical models for the details of optical propagation, and mechanical models for determining the actual structure that exists in the optical system. Previous analysis methods for creating beam envelopes (or cones of light) for use in this obstruction analysis were found to be cumbersome to calculate and take significant time and resources to complete. A new process was developed that takes less time to complete beam envelope analysis, is more accurate and less dependent upon manual node tracking to create the beam envelopes, and eases the burden on the mechanical CAD (computer-aided design) designers to form the beam solids. This algorithm allows rapid generation of beam envelopes for optical system obstruction analysis. Ray trace information is taken from optical design software and used to generate CAD objects that represent the boundary of the beam envelopes for detailed analysis in mechanical CAD software. Matlab is used to call ray trace data from the optical model for all fields and entrance pupil points of interest. These are chosen to be the edge of each space, so that these rays produce the bounding volume for the beam. The x and y global coordinate data is collected on the surface planes of interest, typically an image of the field and entrance pupil internal of the optical system. This x and y coordinate data is then evaluated using a convex hull algorithm, which removes any internal points, which are unnecessary to produce the bounding volume of interest. At this point, tolerances can be applied to expand the size of either the field or aperture, depending on the allocations. Once this minimum set of coordinates on the pupil and field is obtained, a new set of rays is generated between the field plane and aperture plane (or vice-versa). These rays are then evaluated at planes between the aperture and field, at a

Transparent ceramic lamp envelope materials

Energy Technology Data Exchange (ETDEWEB)

Wei, G C [OSRAM SYLVANIA, 71 Cherry Hill Drive, Beverly, MA 01915 (United States)

2005-09-07

Transparent ceramic materials with optical qualities comparable to single crystals of similar compositions have been developed in recent years, as a result of the improved understanding of powder-processing-fabrication- sintering-property inter-relationships. These high-temperature materials with a range of thermal and mechanical properties are candidate envelopes for focused-beam, short-arc lamps containing various fills operating at temperatures higher than quartz. This paper reviews the composition, structure and properties of transparent ceramic lamp envelope materials including sapphire, small-grained polycrystalline alumina, aluminium oxynitride, yttrium aluminate garnet, magnesium aluminate spinel and yttria-lanthana. A satisfactory thermal shock resistance is required for the ceramic tube to withstand the rapid heating and cooling cycles encountered in lamps. Thermophysical properties, along with the geometry, size and thickness of a transparent ceramic tube, are important parameters in the assessment of its resistance to fracture arising from thermal stresses in lamps during service. The corrosive nature of lamp-fill liquid and vapour at high temperatures requires that all lamp components be carefully chosen to meet the target life. The wide range of new transparent ceramics represents flexibility in pushing the limit of envelope materials for improved beamer lamps.

Final deactivation project report on the Source Development Laboratory, building 3029, Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1997-05-01

The purpose of this report is to document the condition of Building 3029 after completion of deactivation activities as outlined by the DOE Nuclear Materials and Facility Stabilization Program (EM-60) guidance documentation. This report outlines the activities conducted to place the facility in a safe and environmentally sound condition for transfer to the DOE Office of Environmental Restoration (EM-40). This report provides a history and profile of the facility prior to commencing deactivation activities and a profile of the building after completion of deactivation activities. Turnover items, such as the post-deactivation surveillance and maintenance (S ampersand M) plan, remaining hazardous materials, radiological controls, safeguards and security, quality assurance, facility operations, and supporting documentation provided in the EM-60 turnover package are discussed. Building 3029 will require access to facilitate required S ampersand M activities to maintain the building safety envelope. building 3029 was stabilized during deactivation so that when transferred to the EM-40 program, only a minimal S ampersand M effort would be required to maintain the building safety envelope. Other than the minimal S ampersand M activities, the building will be unoccupied and the exterior doors locked to prevent unauthorized access. The building will be entered only to perform the required S ampersand M. 5 refs., 7 figs., 3 tabs

Gravitational Waves from Accreting Neutron Stars Undergoing Common-envelope Inspiral

Science.gov (United States)

Holgado, A. Miguel; Ricker, Paul M.; Huerta, E. A.

2018-04-01

The common-envelope phase is a likely formation channel for close binary systems containing compact objects. Neutron stars in common envelopes accrete at a fraction of the Bondi–Hoyle–Lyttleton accretion rate, since the stellar envelope is inhomogeneous, but they may still be able to accrete at hypercritical rates (though not enough to become black holes). We show that common-envelope systems consisting of a neutron star with a massive primary may be gravitational-wave (GW) sources detectable in the Advanced LIGO band as far away as the Magellanic Clouds. To characterize their evolution, we perform orbital integrations using 1D models of 12 M ⊙ and 20 M ⊙ primaries, considering the effects of density gradient on the accretion onto the NS and spin evolution. From the range of possible accretion rates relevant to common-envelope evolution, we find that these systems may be louder GW sources than low-mass X-ray binaries like Sco X-1, which are currently the target of directed searches for continuous GWs. We also find that their strain amplitude signal may allow for novel constraints on the orbital separation and inspiral timescale in common envelopes when combined with pre-common-envelope electromagnetic observations.

Novel Real-Time Flight Envelope Monitoring System, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — The proposed innovation is an aircraft flight envelope monitoring system that will provide real-time in-cockpit estimations of aircraft flight envelope boundaries....

System impact of energy efficient building refurbishment within a district heated region

International Nuclear Information System (INIS)

Lidberg, T.; Olofsson, T.; Trygg, L.

2016-01-01

The energy efficiency of the European building stock needs to be increased in order to fulfill the climate goals of the European Union. To be able to evaluate the impact of energy efficient refurbishment in matters of greenhouse gas emissions, it is necessary to apply a system perspective where not only the building but also the surrounding energy system is taken into consideration. This study examines the impact that energy efficient refurbishment of multi-family buildings has on the district heating and the electricity production. It also investigates the impact on electricity utilization and emissions of greenhouse gases. The results from the simulation of four energy efficiency building refurbishment packages were used to evaluate the impact on the district heating system. The packages were chosen to show the difference between refurbishment actions that increase the use of electricity when lowering the heat demand, and actions that lower the heat demand without increasing the electricity use. The energy system cost optimization modeling tool MODEST (Model for Optimization of Dynamic Energy Systems with Time-Dependent Components and Boundary Conditions) was used. When comparing two refurbishment packages with the same annual district heating use, this study shows that a package including changes in the building envelope decreases the greenhouse gas emissions more than a package including ventilation measures. - Highlights: • Choice of building refurbishment measures leads to differences in system impact. • Building refurbishment in district heating systems reduces co-produced electricity. • Valuing biomass as a limited resource is crucial when assessing global GHG impact. • Building envelope measures decrease GHG (greenhouse gas) emissions more than ventilation measures.

Balancing energy and daylighting performances for envelope design: A new index and proposition of a case study in Hong Kong

International Nuclear Information System (INIS)

Xie, Jing Chao; Xue, Peng; Mak, Cheuk Ming; Liu, Jia Ping

2017-01-01

Highlights: •Daylighting and energy performances were studied simultaneously. •Energy demands of lighting and air-conditioning systems were both included. •Luminous comfort was quantified by Ave. DA 300 with the range from 29.6% to 57.8%. •Energy Daylight Rate was proposed as a simple multi-objective optimization approach. •Optimal scenarios for all directions were tested and chosen by EDR method. -- Abstract: Being healthy and energy saving have become two important principles of building development. Daylight is an influential factor with the characteristics of both photometry and radiometry. Irradiance brings solar heat gains that transfer to building cooling load, while illuminance provides a luminous environment and affects artificial lighting system at the same time. To balance the energy and daylighting performances, it is reasonable to minimize the environmental load under moderate comfort conditions. This study first quantified luminous comfort with a dynamic daylighting metric, average daylight autonomy (Ave. DA 300 ), from a questionnaire survey and simulation work. The benchmark of this metric should range from 29.6% to 57.8% for high-rise residential buildings. With this guideline, the Hong Kong public housing units is found that part of units lack of daylight due to the high building floor and density, while some units have potential to save energy by compromising daylighting performance. Therefore, a new index, energy daylight rate (EDR), is proposed to help decide the best scenario of envelope design for both daylighting and shading purposes. The results show that opening a secondary window is an efficient way to bring more light in and lengthening overhang is an efficient way to block excessive sunlight. This method and the new index are proved to have the ability to help defining proper building envelope design at the early stage.

Field Testing of Energy-Efficient Flood-Damage-Resistant Residential Envelope Systems Summary Report

Energy Technology Data Exchange (ETDEWEB)

Aglan, H.

2005-08-04

The primary purpose of the project was to identify materials and methods that will make the envelope of a house flood damage resistant. Flood damage resistant materials and systems are intended to be used to repair houses subsequent to flooding. This project was also intended to develop methods of restoring the envelopes of houses that have been flooded but are repairable and may be subject to future flooding. Then if the house floods again, damage will not be as extensive as in previous flood events and restoration costs and efforts will be minimized. The purpose of the first pair of field tests was to establish a baseline for typical current residential construction practice. The first test modules used materials and systems that were commonly found in residential envelopes throughout the U.S. The purpose of the second pair of field tests was to begin evaluating potential residential envelope materials and systems that were projected to be more flood-damage resistant and restorable than the conventional materials and systems tested in the first pair of tests. The purpose of testing the third slab-on-grade module was to attempt to dry flood proof the module (no floodwater within the structure). If the module could be sealed well enough to prevent water from entering, then this would be an effective method of making the interior materials and systems flood damage resistant. The third crawl space module was tested in the same manner as the previous modules and provided an opportunity to do flood tests of additional residential materials and systems. Another purpose of the project was to develop the methodology to collect representative, measured, reproducible (i.e. scientific) data on how various residential materials and systems respond to flooding conditions so that future recommendations for repairing flood damaged houses could be based on scientific data. An additional benefit of collecting this data is that it will be used in the development of a standard test

Global Envelope Tests for Spatial Processes

DEFF Research Database (Denmark)

Myllymäki, Mari; Mrkvička, Tomáš; Grabarnik, Pavel

2017-01-01

Envelope tests are a popular tool in spatial statistics, where they are used in goodness-of-fit testing. These tests graphically compare an empirical function T(r) with its simulated counterparts from the null model. However, the type I error probability α is conventionally controlled for a fixed d......) the construction of envelopes for a deviation test. These new tests allow the a priori selection of the global α and they yield p-values. We illustrate these tests using simulated and real point pattern data....

Global envelope tests for spatial processes

DEFF Research Database (Denmark)

Myllymäki, Mari; Mrkvička, Tomáš; Grabarnik, Pavel

Envelope tests are a popular tool in spatial statistics, where they are used in goodness-of-fit testing. These tests graphically compare an empirical function T(r) with its simulated counterparts from the null model. However, the type I error probability α is conventionally controlled for a fixed......) the construction of envelopes for a deviation test. These new tests allow the a priori selection of the global α and they yield p-values. We illustrate these tests using simulated and real point pattern data....

A RISK BASED METHODOLOGY TO ASSESS THE ENERGY EFFICIENCY IMPROVEMENTS IN TRADITIONALLY CONSTRUCTED BUILDINGS

Directory of Open Access Journals (Sweden)

D. Herrera

2013-07-01

Full Text Available In order to achieve the CO2 reduction targets set by the Scottish government, it will be necessary to improve the energy efficiency of existing buildings. Within the total Scottish building stock, historic and traditionally constructed buildings are an important proportion, in the order of 19 % (Curtis, 2010, and represent cultural, emotional and identity values that should be protected. However, retrofit interventions could be a complex operation because of the several aspects that are involved in the hygrothermal performance of traditional buildings. Moreover, all these factors interact with each other and therefore need to be analysed as a whole. Upgrading the envelope of traditional buildings may produce severe changes to the moisture migration leading to superficial or interstitial condensation and thus fabric decay and mould growth. Retrofit projects carried out in the past have failed because of the misunderstanding, or the lack of expert prediction, of the potential consequences associated to the envelope's alteration. The evaluation of potential risks, prior to any alteration on building's physics in order to improve its energy efficiency, is critical to avoid future damage on the wall's performance or occupants' health and well being. The aim of this PhD research project is to point out the most critical aspects related to the energy efficiency improvement of traditional buildings and to develop a risk based methodology that helps owners and practitioners during the decision making process.

Characteristics between the meshing pairs with different envelope profile in single screw compressors

Science.gov (United States)

Huang, R.; Liu, F.; Li, T.; Feng, Q.

2017-08-01

Single screw compressors have been used in various industrial fields. However, because the star-wheel teeth are easy to wear, the market for the development of single screw compressors is limited. In order to extend the service life of the star-wheel, researchers have developed different kinds of star-wheel tooth profile, such as single line envelope profile, single column envelope profile, and multi-column envelope profile. These profiles greatly affect the lubrication characteristics between the star-wheel teeth and the screw grooves. In this article, the lubrication characteristics between the meshing pairs with different envelope profiles are analyzed. Results show that the pressure peak of the single line envelope profile, single column envelope profile, and multi-column envelope profile are 3.23×105Pa, 3.38×105Pa, and 4.31×105Pa, respectively. This means that the multi-column enveloped meshing pair can resist the biggest external impact load. The deviation angle (γ) of the single line envelope profile, single column envelope profile, and multi-column envelope profile are 0.0139°~0.0286°, 0.0225°~0.0306° and 0.0122°~0.0262°, respectively. Thus, the self-balancing ability of the multi-column enveloped meshing pair is the strongest, and the oil film thickness on both sides of the multi-column enveloped star-wheel tooth is the most reasonable, which indicates a good lubrication state during operation, that is, longer operation life of the star-wheel teeth.

Analysis of energy efficiency retrofit schemes for heating, ventilating and air-conditioning systems in existing office buildings based on the modified bin method

International Nuclear Information System (INIS)

Wang, Zhaoxia; Ding, Yan; Geng, Geng; Zhu, Neng

2014-01-01

Highlights: • A modified bin method is adopted to propose and optimize the EER schemes. • A case study is presented to demonstrate the analysis procedures of EER schemes. • Pertinent EER schemes for HVAC systems are proposed for the object building. - Abstract: Poor thermal performance of building envelop and low efficiencies of heating, ventilating and air-conditioning (HVAC) systems can always be found in the existing office buildings with large energy consumption. This paper adopted a modified bin method to propose and optimize the energy efficiency retrofit (EER) schemes. An existing office building in Tianjin was selected as an example to demonstrate the procedures of formulating the design scheme. Pertinent retrofit schemes for HVAC system were proposed after the retrofit of building envelop. With comprehensive consideration of energy efficiency and economic benefits, the recommended scheme that could improve the overall energy efficiency by 71.20% was determined

Stability charts for uniform slopes in soils with nonlinear failure envelopes

OpenAIRE

Eid, Hisham T.

2014-01-01

Based on the results of an extensive parametric study, charts were developed for assessment of the stability of uniform slopes in soils with nonlinear shear strength failure envelopes. The study was conducted using envelopes formed to represent the realistic shapes of soil nonlinear drained strength envelopes and the associated different degrees of nonlinearity. The introduction of a simple methodology to describe the nonlinear envelopes and a stability parameter, the value of which depends o...

Building technolgies program. 1994 annual report

Energy Technology Data Exchange (ETDEWEB)

Selkowitz, S.E.

1995-04-01

The objective of the Building Technologies program is to assist the U.S. building industry in achieving substantial reductions in building sector energy use and associated greenhouse gas emissions while improving comfort, amenity, health, and productivity in the building sector. We have focused our past efforts on two major building systems, windows and lighting, and on the simulation tools needed by researchers and designers to integrate the full range of energy efficiency solutions into achievable, cost-effective design solutions for new and existing buildings. In addition, we are now taking more of an integrated systems and life cycle perspective to create cost-effective solutions for more energy efficient, comfortable, and productive work and living environments. More than 30% of all energy use in buildings is attributable to two sources: windows and lighting. Together they account for annual consumer energy expenditures of more than $50 billion. Each affects not only energy use by other major building systems, but also comfort and productivity-factors that influence building economics far more than does direct energy consumption alone. Windows play a unique role in the building envelope, physically separating the conditioned space from the world outside without sacrificing vital visual contact. Throughout every space in a building, lighting systems facilitate a variety of tasks associated with a wide range of visual requirements while defining the luminous qualities of the indoor environment. Window and lighting systems are thus essential components of any comprehensive building science program.

Computation of Phase Equilibrium and Phase Envelopes

DEFF Research Database (Denmark)

Ritschel, Tobias Kasper Skovborg; Jørgensen, John Bagterp

formulate the involved equations in terms of the fugacity coefficients. We present expressions for the first-order derivatives. Such derivatives are necessary in computationally efficient gradient-based methods for solving the vapor-liquid equilibrium equations and for computing phase envelopes. Finally, we......In this technical report, we describe the computation of phase equilibrium and phase envelopes based on expressions for the fugacity coefficients. We derive those expressions from the residual Gibbs energy. We consider 1) ideal gases and liquids modeled with correlations from the DIPPR database...... and 2) nonideal gases and liquids modeled with cubic equations of state. Next, we derive the equilibrium conditions for an isothermal-isobaric (constant temperature, constant pressure) vapor-liquid equilibrium process (PT flash), and we present a method for the computation of phase envelopes. We...

The internal envelope. A new way to conceive the internal environment.

Directory of Open Access Journals (Sweden)

Christina Conti

2009-06-01

Full Text Available The article investigates the most recent tendencies in terms of design experimentation and technological innovation concerning the technical elements of the internal envelope, focusing in particular to the mobile and dry-assembled systems as vertical partitions, raised floors and false ceilings, which show the tendency to become a sort of internal “shell”, separated from the structural systems of the building and equipped with all devices finalized to the generation and maintenance of the thermal, acoustic and luminous comfort. From the analysis of the tendencies it seems that the concept of an internal environment defined through this kind of “shell” can be one of the possible, if not prevailing, directions, in order to easily respond to functional and aesthetical requests for interior spaces.

SAFEGUARDS ENVELOPE: PREVIOUS WORK AND EXAMPLES

International Nuclear Information System (INIS)

Metcalf, Richard; Bevill, Aaron; Charlton, William; Bean, Robert

2008-01-01

The future expansion of nuclear power will require not just electricity production but fuel cycle facilities such as fuel fabrication and reprocessing plants. As large reprocessing facilities are built in various states, they must be built and operated in a manner to minimize the risk of nuclear proliferation. Process monitoring has returned to the spotlight as an added measure that can increase confidence in the safeguards of special nuclear material (SNM). Process monitoring can be demonstrated to lengthen the allowable inventory period by reducing accountancy requirements, and to reduce the false positive indications. The next logical step is the creation of a Safeguards Envelope, a set of operational parameters and models to maximize anomaly detection and inventory period by process monitoring while minimizing operator impact and false positive rates. A brief example of a rudimentary Safeguards Envelope is presented, and shown to detect synthetic diversions overlaying a measured processing plant data set. This demonstration Safeguards Envelope is shown to increase the confidence that no SNM has been diverted with minimal operator impact, even though it is based on an information sparse environment. While the foundation on which a full Safeguards Envelope can be built has been presented in historical demonstrations of process monitoring, several requirements remain yet unfulfilled. Future work will require reprocessing plant transient models, inclusion of 'non-traditional' operating data, and exploration of new methods of identifying subtle events in transient processes

The nuclear envelope from basic biology to therapy.

Science.gov (United States)

Worman, Howard J; Foisner, Roland

2010-02-01

The nuclear envelope has long been a focus of basic research for a highly specialized group of cell biologists. More recently, an expanding group of scientists and physicians have developed a keen interest in the nuclear envelope since mutations in the genes encoding lamins and associated proteins have been shown to cause a diverse range of human diseases often called laminopathies or nuclear envelopathies. Most of these diseases have tissue-selective phenotypes, suggesting that the nuclear envelope must function in cell-type- and developmental-stage-specific processes such as chromatin organization, regulation of gene expression, controlled nucleocytoplasmic transport and response to stress in metazoans. On 22-23 April 2009, Professor Christopher Hutchison organized the 4th British Nuclear Envelope Disease and Chromatin Organization meeting at the College of St Hild and St Bede at Durham University, sponsored by the Biochemical Society. In attendance were investigators with one common interest, the nuclear envelope, but with diverse expertise and training in animal and plant cell biology, genetics, developmental biology and medicine. We were each honoured to be keynote speakers. This issue of Biochemical Society Transactions contains papers written by some of the presenters at this scientifically exciting meeting, held in a bucolic setting where the food was tasty and the wine flowed freely. Perhaps at the end of this excellent meeting more questions were raised than answered, which will stimulate future research. However, what became clear is that the nuclear envelope is a cellular structure with critical functions in addition to its traditional role as a barrier separating the nuclear and cytoplasmic compartments in interphase eukaryotic cells.

Torsin Mediates Primary Envelopment of Large Ribonucleoprotein Granules at the Nuclear Envelope

Directory of Open Access Journals (Sweden)

Vahbiz Jokhi

2013-04-01

Full Text Available A previously unrecognized mechanism through which large ribonucleoprotein (megaRNP granules exit the nucleus is by budding through the nuclear envelope (NE. This mechanism is akin to the nuclear egress of herpes-type viruses and is essential for proper synapse development. However, the molecular machinery required to remodel the NE during this process is unknown. Here, we identify Torsin, an AAA-ATPase that in humans is linked to dystonia, as a major mediator of primary megaRNP envelopment during NE budding. In torsin mutants, megaRNPs accumulate within the perinuclear space, and the messenger RNAs contained within fail to reach synaptic sites, preventing normal synaptic protein synthesis and thus proper synaptic bouton development. These studies begin to establish the cellular machinery underlying the exit of megaRNPs via budding, offer an explanation for the “nuclear blebbing” phenotype found in dystonia models, and provide an important link between Torsin and the synaptic phenotypes observed in dystonia.

Inversion of Auditory Spectrograms, Traditional Spectrograms, and Other Envelope Representations

DEFF Research Database (Denmark)

Decorsière, Remi Julien Blaise; Søndergaard, Peter Lempel; MacDonald, Ewen

2015-01-01

Envelope representations such as the auditory or traditional spectrogram can be defined by the set of envelopes from the outputs of a filterbank. Common envelope extraction methods discard information regarding the fast fluctuations, or phase, of the signal. Thus, it is difficult to invert, or re...... to the framework is proposed, which leads to a more accurate inversion of traditional spectrograms...

14 CFR 29.1517 - Limiting height-speed envelope.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limiting height-speed envelope. 29.1517... Operating Limitations § 29.1517 Limiting height-speed envelope. For Category A rotorcraft, if a range of... following power failure, the range of heights and its variation with forward speed must be established...

Kinetic Super-Resolution Long-Wave Infrared (KSR LWIR) Thermography Diagnostic for Building Envelopes: Scott AFB, IL

Science.gov (United States)

2015-08-18

structures. The system software au- tomatically analyzes the thermal imagery and provides a custom report for each building that recommends cost-effective...possible using traditional thermogra- phy. This includes building facade data and building orientation. The au- tomated data processing system also

Energy efficiency façade design in high-rise apartment buildings using the calculation of solar heat transfer through windows with shading devices

Science.gov (United States)

Ha, P. T. H.

2018-04-01

The architectural design orientation at the first design stage plays a key role and has a great impact on the energy consumption of a building throughout its life-cycle. To provide designers with a simple and useful tool in quantitatively determining and simply optimizing the energy efficiency of a building at the very first stage of conceptual design, a factor namely building envelope energy efficiency (Khqnl ) should be investigated and proposed. Heat transfer through windows and other glazed areas of mezzanine floors accounts for 86% of overall thermal transfer through building envelope, so the factor Khqnl of high-rise buildings largely depends on shading solutions. The author has established tables and charts to make reference to the values of Khqnl factor in certain high-rise apartment buildings in Hanoi calculated with a software program subject to various inputs including: types and sizes of shading devices, building orientations and at different points of time to be respectively analyzed. It is possible and easier for architects to refer to these tables and charts in façade design for a higher level of energy efficiency.

Building America Case Study: Savannah Gardens, Savannah, Georgia

Energy Technology Data Exchange (ETDEWEB)

2016-03-01

Southface Energy Institute (Southface) partnered with owners and/or builders with various market constraints and ultimate goals for three projects in different climate zones: Savannah, GA (CZ 2), Clemson, SC (CZ 3), and LaFayette, GA (CZ 4). This report documents the design process, computational energy modeling, construction, envelope performance metrics, long-term monitoring results, and successes and failures of the design and execution of these high performance homes. The three bedroom/two bathroom test home in Savannah Gardens on an elevated slab foundation has a semi-conditioned, encapsulated attic. A neighboring home built to EarthCraft specifications was also monitored as a control for exterior foam insulation and a heat pump water heater (HPWH). For the JMC Patrick Square, a single-story project in Clemson, the small-scale production builder wanted to increase their level of energy efficiency beyond their current green building practices, including bringing ducts into conditioned space. Through a combination of upgrade measures the team met this goal and achieved many Zero Energy Ready Home requirements. LaFayette Housing Authority undertook a development of 30 affordable rental housing units in 15 duplexes in LaFayette, GA. Because they would be long-term owners, their priorities were low utility bills for the residents and durable, maintainable buildings. The team employed BEopt to optimize building envelope and systems choices, including 2x6 advanced framed walls, insulated slab, and heat pump water heater in a utility closet which was ducted to/from an encapsulated attic.

Boundaries, injective envelopes, and reduced crossed products

DEFF Research Database (Denmark)

Bryder, Rasmus Sylvester

In this dissertation, we study boundary actions, equivariant injective envelopes, as well as theideal structure of reduced crossed products. These topics have recently been linked to thestudy of C-simple groups, that is, groups with simple reduced group C-algebras.In joint work with Matthew Kennedy......, we consider reduced twisted crossed products overC-simple groups. For any twisted C-dynamical system over a C-simple group, we provethat there is a one-to-one correspondence between maximal invariant ideals in the underlyingC-algebra and maximal ideals in the reduced crossed product. When......*-algebras, and relate the intersection property for group actions on unital C*-algebras to the intersection property for theequivariant injective envelope. Moreover, we also prove that the equivariant injective envelopeof the centre of the injective envelope of a unital C*-algebra can be regarded as a C...

Simulation Speed Analysis and Improvements of Modelica Models for Building Energy Simulation

Energy Technology Data Exchange (ETDEWEB)

Jorissen, Filip; Wetter, Michael; Helsen, Lieve

2015-09-21

This paper presents an approach for speeding up Modelica models. Insight is provided into how Modelica models are solved and what determines the tool’s computational speed. Aspects such as algebraic loops, code efficiency and integrator choice are discussed. This is illustrated using simple building simulation examples and Dymola. The generality of the work is in some cases verified using OpenModelica. Using this approach, a medium sized office building including building envelope, heating ventilation and air conditioning (HVAC) systems and control strategy can be simulated at a speed five hundred times faster than real time.

Modeling of Dynamic Responses in Building Insulation

Directory of Open Access Journals (Sweden)

Anna Antonyová

2015-10-01

Full Text Available In this research a measurement systemwas developedfor monitoring humidity and temperature in the cavity between the wall and the insulating material in the building envelope. This new technology does not disturb the insulating material during testing. The measurement system can also be applied to insulation fixed ten or twenty years earlier and sufficiently reveals the quality of the insulation. A mathematical model is proposed to characterize the dynamic responses in the cavity between the wall and the building insulation as influenced by weather conditions.These dynamic responses are manifested as a delay of both humidity and temperature changes in the cavity when compared with the changes in the ambient surrounding of the building. The process is then modeled through numerical methods and statistical analysis of the experimental data obtained using the new system of measurement.

Cool products for building envelope - Part I: Development and lab scale testing

NARCIS (Netherlands)

Revel, G.M.; Martarelli, M.; Emiliani, M.; Gozalbo, A.; Orts, M.J.; Bengochea, M.T.; Guaita Delgado, L.; Gaki, A.; Katsiapi, A.; Taxiarchou, M.; Arabatzis, I.; Fasaki, I.; Hermanns, S.

2014-01-01

The paper describes the methodology followed for the development of new cool products in order to widen the range of existing solutions both including coloured (even dark) materials and extending the application also to building vertical components. Cool coloured ceramic tiles and acrylic paints for

The Arabidopsis Nuclear Pore and Nuclear Envelope

OpenAIRE

Meier, Iris; Brkljacic, Jelena

2010-01-01

The nuclear envelope is a double membrane structure that separates the eukaryotic cytoplasm from the nucleoplasm. The nuclear pores embedded in the nuclear envelope are the sole gateways for macromolecular trafficking in and out of the nucleus. The nuclear pore complexes assembled at the nuclear pores are large protein conglomerates composed of multiple units of about 30 different nucleoporins. Proteins and RNAs traffic through the nuclear pore complexes, enabled by the interacting activities...

Comparative study of commercial building energy-efficiency retrofit policies in four pilot cities in China

International Nuclear Information System (INIS)

Hou, Jing; Liu, Yisheng; Wu, Yong; Zhou, Nan; Feng, Wei

2016-01-01

The energy efficiency of existing commercial buildings is more challenging to regulate and improve than the energy efficiency of new constructions. In 2011 and 2012, the Chinese Government selected four cities- Shanghai, Tianjin, Shenzhen, and Chongqing- to implement pilot commercial building energy efficiency retrofit program. Based on site surveys and expert interviews in these pilot cities, this research conducted a comparative analysis on incentive policies of local city level. The analysis results show that policy designs of existing commercial buildings should be further improved. The aspects that influence the implementation effect in the future, such as subsidy level, installments, and business model promotion, should be specified in the policy clauses. Referring to the technical solution and cost-benefit in Chongqing, we found that lighting system is the most common retrofit objects while envelope system is the least common one. And the subsidy incentive is greatest for educational buildings, followed by office buildings. In the end, we further discussed the problems and obstacles in commercial building retrofit market, and provided a series of recommendations. - Highlights: • Data and information were collected through site surveys to the four pilot cities. • Policy design and effectiveness in four cities were comparatively analyzed. • Well-designed policy increases market response, energy savings and EMC adoption. • Lighting is the most common retrofit while envelope is the least common one. • Subsidy incentive is greatest for educational buildings due to the utility tariff.

Green buildings: Implications for acousticians

Science.gov (United States)

Noble, Michael R.

2005-04-01

This presentation will deal with the practical implications of green design protocols of the US Green Building Council on interior acoustics of buildings. Three areas of particular consequence to acousticians will be discussed. Ventilation Systems: reduced energy consumption goals dictate reliance on natural cooling and ventilation using ambient air when possible. The consequent large openings in the building envelope to bring fresh air into rooms, and similar sized openings to transfer the mixed air out, can severely compromise the noise isolation of the rooms concerned. Radiant Cooling: the heavy concrete floors of buildings can be used as a thermal flywheel to lessen the cooling load, which forces the concrete ceilings to be exposed to the occupied rooms for heat transfer, and strictly limits the application of acoustical absorption on the ceilings. This challenges the room acoustics design. Green Materials: the LEED protocols require the elimination of potentially harmful finishes, including fibrous materials which may impact air quality or contribute to health problems. Since the backbone of sound absorption is glass and mineral fibres, this further challenges provision of superior room acoustics. Examples and commentary will be provided based on current and recent projects.

Solar potential in existing urban layouts—Critical overview of the existing building stock in Slovenian context

International Nuclear Information System (INIS)

Košir, Mitja; Capeluto, Isaac Guedi; Krainer, Aleš; Kristl, Živa

2014-01-01

In recent years implementation of sustainable building design in the EU has become one of the key issues in reducing energy dependence. In this context efficient use of solar potential incident on building envelope is essential. The goal of the study is to evaluate the influence of interventions required by the new Slovenian legislation and to propose general site planning guidelines. Special emphasis is devoted to the existing building stock, which is due for refurbishment. The study is carried out on the basis of seven typical urban layouts, which are assessed according to the shape of layout, density, building orientation and design. The calculations are carried out with the program SHADING. The study showed that the existing layouts are not as problematic as had been expected and that form and orientation of buildings present a major challenge. Nevertheless, the quality and the duration of insolation are highly dependent on the specifics of each case. The study showed that by respecting the basic rules of good practice in conjunction with the existing requirements no major changes in the existing design principles are needed. - Highlights: • New Slovenian legislation regarding minimum insolation of building envelope. • Seven typical urban layouts were analysed. • Requirements and rules of good practice result in adequate insolation. • Duration of insolation is highly dependent on the specifics of each case

Indoor-Outdoor Air Leakage of Apartments and Commercial Buildings

Energy Technology Data Exchange (ETDEWEB)

Price, P.N.; Shehabi, A.; Chan, R.W.; Gadgil, A.J.

2006-06-01

We compiled and analyzed available data concerning indoor-outdoor air leakage rates and building leakiness parameters for commercial buildings and apartments. We analyzed the data, and reviewed the related literature, to determine the current state of knowledge of the statistical distribution of air exchange rates and related parameters for California buildings, and to identify significant gaps in the current knowledge and data. Very few data were found from California buildings, so we compiled data from other states and some other countries. Even when data from other developed countries were included, data were sparse and few conclusive statements were possible. Little systematic variation in building leakage with construction type, building activity type, height, size, or location within the u.s. was observed. Commercial buildings and apartments seem to be about twice as leaky as single-family houses, per unit of building envelope area. Although further work collecting and analyzing leakage data might be useful, we suggest that a more important issue may be the transport of pollutants between units in apartments and mixed-use buildings, an under-studied phenomenon that may expose occupants to high levels of pollutants such as tobacco smoke or dry cleaning fumes.

Vacuum Insulation Panels (VIPs) for building construction industry - A review of the contemporary developments and future directions

International Nuclear Information System (INIS)

Alam, M.; Singh, H.; Limbachiya, M.C.

2011-01-01

Highlights: → Vacuum Insulation Panels (VIP), a high thermal resistance building insulation. → Review of research into VIPs for building applications. → High cost and uncertainty of service life are two barriers for VIP use in buildings. → SiO 2 /SiN x coated PET laminate- candidate for high barrier VIP envelope. → The optimum combination of VIP core and envelope yet to be determined. -- Abstract: Demand for energy efficient buildings has increased drastically in recent years and this trend will continue in the future. Insulating building elements will play a key role in meeting this demand by reducing heat losses through the building fabric. Due to their higher thermal resistance, Vacuum Insulation Panels (VIPs) would be a more energy efficient alternative to conventional building insulation materials. Thus, efforts to develop VIPs with characteristics suitable for applications to new and existing buildings are underway. This paper provides a review of important contemporary developments towards producing VIPs using various materials such as glass fibre, foams, perlite and fibre/powder composites. The limitations of the materials currently used to fabricate VIPs have not been emphasised in detail in previous review papers published. Selection criteria, methods to measure important properties of VIPs and analytical and numerical models presented in the past have been detailed. Limitations of currently employed design tools along with potential future materials such as Nano/microcellular foams and SiO x /SiN x coatings for use in VIPs are also described.

Adaptive building skin structures

International Nuclear Information System (INIS)

Del Grosso, A E; Basso, P

2010-01-01

The concept of adaptive and morphing structures has gained considerable attention in the recent years in many fields of engineering. In civil engineering very few practical applications are reported to date however. Non-conventional structural concepts like deployable, inflatable and morphing structures may indeed provide innovative solutions to some of the problems that the construction industry is being called to face. To give some examples, searches for low-energy consumption or even energy-harvesting green buildings are amongst such problems. This paper first presents a review of the above problems and technologies, which shows how the solution to these problems requires a multidisciplinary approach, involving the integration of architectural and engineering disciplines. The discussion continues with the presentation of a possible application of two adaptive and dynamically morphing structures which are proposed for the realization of an acoustic envelope. The core of the two applications is the use of a novel optimization process which leads the search for optimal solutions by means of an evolutionary technique while the compatibility of the resulting configurations of the adaptive envelope is ensured by the virtual force density method

Asymmetry of the SN 1987A envelope

International Nuclear Information System (INIS)

Chugaj, N.N.

1991-01-01

The origin of the peculiar structure in the profiles of the emission lines observed in the spectrum of SN 1987A, namely, (1) redshift of maxima, and (2) fine structure of hydrogen lines, is considered. Among the three proposed hypothesis for the redshift, at least two (electron scattering in the spherically-symmetric envelope, and geometrical effects in the fragmented envelope) have serious drawbacks. More favorable is the third hypothesis which invokes asymmetric distribution of 56 Ni and of the iron-peak elements

Identification of new genes in a cell envelope-cell division gene cluster of Escherichia coli: cell envelope gene murG.

Science.gov (United States)

Salmond, G P; Lutkenhaus, J F; Donachie, W D

1980-01-01

We report the identification, cloning, and mapping of a new cell envelope gene, murG. This lies in a group of five genes of similar phenotype (in the order murE murF murG murC ddl) all concerned with peptidoglycan biosynthesis. This group is in a larger cluster of at least 10 genes, all of which are involved in some way with cell envelope growth. Images PMID:6998962

Digital image envelope: method and evaluation

Science.gov (United States)

Huang, H. K.; Cao, Fei; Zhou, Michael Z.; Mogel, Greg T.; Liu, Brent J.; Zhou, Xiaoqiang

2003-05-01

Health data security, characterized in terms of data privacy, authenticity, and integrity, is a vital issue when digital images and other patient information are transmitted through public networks in telehealth applications such as teleradiology. Mandates for ensuring health data security have been extensively discussed (for example The Health Insurance Portability and Accountability Act, HIPAA) and health informatics guidelines (such as the DICOM standard) are beginning to focus on issues of data continue to be published by organizing bodies in healthcare; however, there has not been a systematic method developed to ensure data security in medical imaging Because data privacy and authenticity are often managed primarily with firewall and password protection, we have focused our research and development on data integrity. We have developed a systematic method of ensuring medical image data integrity across public networks using the concept of the digital envelope. When a medical image is generated regardless of the modality, three processes are performed: the image signature is obtained, the DICOM image header is encrypted, and a digital envelope is formed by combining the signature and the encrypted header. The envelope is encrypted and embedded in the original image. This assures the security of both the image and the patient ID. The embedded image is encrypted again and transmitted across the network. The reverse process is performed at the receiving site. The result is two digital signatures, one from the original image before transmission, and second from the image after transmission. If the signatures are identical, there has been no alteration of the image. This paper concentrates in the method and evaluation of the digital image envelope.

Annual energy analysis of concrete containing phase change materials for building envelopes

International Nuclear Information System (INIS)

Thiele, Alexander M.; Jamet, Astrid; Sant, Gaurav; Pilon, Laurent

2015-01-01

Highlights: • Adding PCM to concrete walls can significantly reduce the cooling needs of buildings. • Climate, season, and wall orientation strongly affect energy and cost savings. • The PCM melting temperature should be near the desired indoor temperature. • Benefits are maximum for outdoor temperature oscillating around set indoor temperature. • Adding PCM had little effect on heating energy needs and associated cost savings. - Abstract: This paper examines the annual energy and cost savings potential of adding microencapsulated phase change material to the exterior concrete walls of an average-sized single family home in California climate zones 3 (San Francisco, CA) and 9 (Los Angeles, CA). The annual energy and cost savings were larger for South- and West-facing walls than for other walls. They were also the largest when the phase change temperature was near the desired indoor temperature. The addition of microencapsulated phase change material to the building walls reduced the cooling load in summer substantially more than the heating load in winter. This was attributed to the cold winter temperatures resulting in nearly unidirectional heat flux on many days. The annual cooling load reduction in an average-sized single family home in San Francisco and in Los Angeles ranged from 85% to 100% and from 53% to 82%, respectively, for phase change material volume fraction ranging from 0.1 to 0.3. The corresponding annual electricity cost savings ranged from $36 to $42 in San Francisco and from $94 to $143 in Los Angeles. From an energy standpoint, the best climate for using building materials containing uniformly distributed microencapsulated phase change material would have outdoor temperature oscillations centered around the desired indoor temperature for the entire year

Early Site Permit Demonstration Program: Plant parameters envelope report

International Nuclear Information System (INIS)

1993-03-01

The Early Site Permit (ESP) Demonstration Program is the nuclear industry's initiative for piloting the early resolution of siting-related issues before the detailed design proceedings of the combined operating license review. The ESP Demonstration Program consists of three phases. The plant parameters envelopes task is part of Phase 1, which addresses the generic review of applicable federal regulations and develops criteria for safety and environmental assessment of potential sites. The plant parameters envelopes identify parameters that characterize the interface between an ALWR design and a potential site, and quantify the interface through values selected from the Utility Requirements Documents, vendor design information, or engineering assessments. When augmented with site-specific information, the plant parameters envelopes provide sufficient information to allow ESPs to be granted based on individual ALWR design information or enveloping design information for the evolutionary, passive, or generic ALWR plants. This document is expected to become a living document when used by future applicants

State-of-the-art of intelligent building envelopes in the context of intelligent technical systems

NARCIS (Netherlands)

Böke, J.; Knaack, U.; Hemmerling, Marco

2018-01-01

The high and increasing requirements concerning energy consumption and the interior comfort of buildings result in a demand for more efficient façade constructions. In its role as a mediator between the exterior and interior of a building, the façade takes on a multitude of functions with effect

Thermal mass vs. insulation building envelope design in six climatic regions of South Africa

CSIR Research Space (South Africa)

Kumirai, T

2012-02-01

Full Text Available is defined in Ecotect as a homogenous enclosed volume of air. In most cases this corresponds to a single room. It is assumed that the air within a zone is able to mix freely. Every room in the simulation model was defined as distinct thermal zone... of the Ecotect simulation model and simulation of houses with base case characteristics and energy efficient measures in six South African cities. 3.1 Building infiltration rate measurements High infiltration rates means a leaky building meaning...

Thermal and Energy Performance of Conditioned Building Due To Insulated Sloped Roof

Science.gov (United States)

Irwan, Suhandi Syiful; Ahmed, Azni Zain; Zakaria, Nor Zaini; Ibrahim, Norhati

2010-07-01

For low-rise buildings in equatorial region, the roof is exposed to solar radiation longer than other parts of the envelope. Roofs are to be designed to reject heat and moderate the thermal impact. These are determined by the design and construction of the roofing system. The pitch of roof and the properties of construction affect the heat gain into the attic and subsequently the indoor temperature of the living spaces underneath. This finally influences the thermal comfort conditions of naturally ventilated buildings and cooling load of conditioned buildings. This study investigated the effect of insulated sloping roof on thermal energy performance of the building. A whole-building thermal energy computer simulation tool, Integrated Environmental Solution (IES), was used for the modelling and analyses. A building model with dimension of 4.0 m × 4.0 m × 3.0 m was designed with insulated roof and conventional construction for other parts of the envelope. A 75 mm conductive insulation material with thermal conductivity (k-value) of 0.034 Wm-1K-1 was installed underneath the roof tiles. The building was modelled with roof pitch angles of 0° , 15°, 30°, 45°, 60° and simulated for the month of August in Malaysian climate conditions. The profile for attic temperature, indoor temperature and cooling load were downloaded and evaluated. The optimum roof pitch angle for best thermal performance and energy saving was identified. The results show the pitch angle of 0° is able to mitigate the thermal impact to provide the best thermal condition with optimum energy savings. The maximum temperature difference between insulated and non-insulted roof for attic (AtticA-B) and indoor condition (IndoorA-B) is +7.8 °C and 0.4 °C respectively with an average energy monthly savings of 3.9 %.

Results. Building integrated energy supply; Resultater. Bygningsintegreret energiforsyning

Energy Technology Data Exchange (ETDEWEB)

Jensen, Rasmus L.; Noergaard, J.; Daniels, O.; Justesen, R.O.

2011-08-15

In the future, buildings will not only act as consumers of energy but as producers as well. For these ''prosumers'', energy production by use of solar panels, photovoltaics and heat pumps etc will be essential. The objective of this project was to find the most optimal combinations of building insulation and use of renewable energy sources in existing buildings in terms of economics and climate impacts. Five houses were analyzed based on different personal load, consumption profiles, solar orientation and proposed building envelope improvements and use of combinations of renewable energy systems. The analysis was conducted by making a large number of simulations of which the best combinations were selected. The final result takes form of a single top-50 list with the best combinations of energy systems according to CO{sub 2} emission, energy consumption and economics. The present report contains the conclusions of and comments on the project's results. (ln)

Beam envelope profile of non-centrosymmetric polygonal phase space

International Nuclear Information System (INIS)

Chen Yinbao; Xie Xi

1984-01-01

The general theory of beam envelope profile of non-centrosymmetric polygonal phase space is developed. By means of this theory the beam envelope profile of non-centrosymmetric polygonal phase space can be calculated directly. An example is carried out in detail to show the practical application of the theory

Energy in buildings: Efficiency, renewables and storage

Science.gov (United States)

Koebel, Matthias M.

2017-07-01

This lecture summary provides a short but comprehensive overview on the "energy and buildings" topic. Buildings account for roughly 40% of the global energy demands. Thus, an increased adoption of existing and upcoming materials and solutions for the building sector represents an enormous potential to reduce building related energy demands and greenhouse gas emissions. The central question is how the building envelope (insulation, fenestration, construction style, solar control) affects building energy demands. Compared to conventional insulation materials, superinsulation materials such as vacuum insulation panels and silica aerogel achieve the same thermal performance with significantly thinner insulation layers. With low-emissivity coatings and appropriate filler gasses, double and triple glazing reduce thermal losses by up to an order of magnitude compared to old single pane windows, while vacuum insulation and aerogel filled glazing could reduce these even further. Electrochromic and other switchable glazing solutions maximize solar gains during wintertime and minimize illumination demands whilst avoiding overheating in summer. Upon integration of renewable energy systems into the building energy supply, buildings can become both producers and consumers of energy. Combined with dynamic user behavior, temporal variations in the production of renewable energy require appropriate storage solutions, both thermal and electrical, and the integration of buildings into smart grids and energy district networks. The combination of these measures allows a reduction of the existing building stock by roughly a factor of three —a promising, but cost intensive way, to prepare our buildings for the energy turnaround.

Conservation of the egg envelope digestion mechanism of hatching enzyme in euteleostean fishes.

Science.gov (United States)

Kawaguchi, Mari; Yasumasu, Shigeki; Shimizu, Akio; Sano, Kaori; Iuchi, Ichiro; Nishida, Mutsumi

2010-12-01

We purified two hatching enzymes, namely high choriolytic enzyme (HCE; EC 3.4.24.67) and low choriolytic enzyme (LCE; EC 3.4.24.66), from the hatching liquid of Fundulus heteroclitus, which were named Fundulus HCE (FHCE) and Fundulus LCE (FLCE). FHCE swelled the inner layer of egg envelope, and FLCE completely digested the FHCE-swollen envelope. In addition, we cloned three Fundulus cDNAs orthologous to cDNAs for the medaka precursors of egg envelope subunit proteins (i.e. choriogenins H, H minor and L) from the female liver. Cleavage sites of FHCE and FLCE on egg envelope subunit proteins were determined by comparing the N-terminal amino acid sequences of digests with the sequences deduced from the cDNAs for egg envelope subunit proteins. FHCE and FLCE cleaved different sites of the subunit proteins. FHCE efficiently cleaved the Pro-X-Y repeat regions into tripeptides to dodecapeptides to swell the envelope, whereas FLCE cleaved the inside of the zona pellucida domain, the core structure of egg envelope subunit protein, to completely digest the FHCE-swollen envelope. A comparison showed that the positions of hatching enzyme cleavage sites on egg envelope subunit proteins were strictly conserved between Fundulus and medaka. Finally, we extended such a comparison to three other euteleosts (i.e. three-spined stickleback, spotted halibut and rainbow trout) and found that the egg envelope digestion mechanism was well conserved among them. During evolution, the egg envelope digestion by HCE and LCE orthologs was established in the lineage of euteleosts, and the mechanism is suggested to be conserved. © 2010 The Authors Journal compilation © 2010 FEBS.

Energy Performance Indicators in the Swedish Building Procurement Process

Directory of Open Access Journals (Sweden)

Ingrid Allard

2017-10-01

Full Text Available In Sweden, all new buildings need to comply with the National Board of Housing, Building and Planning’s requirement on specific purchased energy (kWh/m2. Accordingly, this indicator is often used to set design criteria in the building procurement process. However, when energy use is measured in finished buildings, the measurements often deviate significantly from the design calculations. The measured specific purchased energy does not necessarily reflect the responsibility of the building contractor, as it is influenced by the building operation, user behavior and climate. Therefore, Swedish building practitioners may prefer other indicators for setting design criteria in the building procurement process. The aim of this study was twofold: (i to understand the Swedish building practitioners’ perspectives and opinions on seven building energy performance indicators (envelope air leakage, U-values for different building parts, average U-value, specific heat loss, heat loss coefficient, specific net energy, and specific purchased energy; and (ii to understand the consequences for the energy performance of multi-family buildings of using the studied indicators to set criteria in the procurement process. The study involved a Delphi approach and simulations of a multi-family case study building. The studied indicators were discussed in terms of how they may meet the needs of the building practitioners when used to set building energy performance criteria in the procurement process.

THE USE OF AIR LAYERS IN BUILDING ENVELOPES FOR ENERGY SAVING DURING AIR CONDITIONING

Directory of Open Access Journals (Sweden)

S. N. Osipov

2017-01-01

Full Text Available Since there are no large natural energy resources in Belarus, energy savings ought to be a point of the special attention. With this regard it is important to develop modern ways of savings during the process of air conditioning inside new buildings with an air layer in the enclosure, especially in translucent ones. The system of ventilation of air layers in the enclosure of a building has been introduced in which air movement is caused by the gravitational and aerodynamic forces. It makes it possible to arrange further ventilation – a natural, forced or a hybrid one. With the purpose of increasing and streamlining natural draught the partitions are used separating the different parts of air layers. For natural ventilation with the use of gravitational forces the holes in the upper and lower parts of the partitions between adjacent air layers are applied. Natural ventilation in the holes of the partitions is regulated by movable shutters, blinds or other adjusting devices. For combined or forced air exchange between adjacent zones of air layers fans are used pumping air from the air layer zones with a higher temperature to zones of air layers with lower temperature and vice versa. When air exchange is forced, in order to intensify the infiltration of air into zones of air layers jets are laid on a hard surface. In order to cool a multi-layered enclosure of a building, where the movement of air between the air layers (that have been formed by internal partitions is being fulfilled by a natural, forced or combined mode, a part of the air or the total air processed inside the building (i.e. conditioned or non-conditioned air cooler as compared with the outside one is being sent to these strata. Combined or forced flow of the air processed inside the building into the air layers is done through the ducts associated with the output channels of the air conditioners. The internal partitions are equipped with the air valve hole.

Retrofitting solutions for two different occupancy levels of educational buildings in tropics

Science.gov (United States)

Yang, Junjing; Pantazaras, Alexandros; Lee, Siew Eang; Santamouris, Mattheos

2018-01-01

Within the multi-functionality of educational buildings, the energy conservation potential can be very different. In addition, among different retrofitting solutions investigated involving interventions on the building envelope, ventilation strategies, artificial lighting systems as well as equipment upgrading, different saving potential would come from different aspects. The opportunities for energy saving potential from the overall point of view and from the detailed aspect view of different retrofitting solutions would be very useful and important for building renovation decision making. This study presents a detailed retrofitting study of two different educational buildings. One represents a building with average occupancy variation and containing mainly offices and labs. The other one represents a building with high occupancy variation and containing mainly lecture rooms and studios. This comparison of the results gives an idea of the different energy saving potential for different types of educational buildings. Principal component analysis is also adopted to investigate the detailed performance of one of the buildings which is influenced stronger by these retrofitting solutions.

Functional incorporation of green fluorescent protein into hepatitis B virus envelope particles

International Nuclear Information System (INIS)

Lambert, Carsten; Thome, Nicole; Kluck, Christoph J.; Prange, Reinhild

2004-01-01

The envelope of hepatitis B virus (HBV), containing the L, M, and S proteins, is essential for virus entry and maturation. For direct visualization of HBV, we determined whether envelope assembly could accommodate the green fluorescent protein (GFP). While the C-terminal addition of GFP to S trans-dominant negatively inhibited empty envelope particle secretion, the N-terminal GFP fusion to S (GFP.S) was co-integrated into the envelope, giving rise to fluorescent particles. Microscopy and topogenesis analyses demonstrated that the proper intracellular distribution and folding of GFP.S, required for particle export were rescued by interprotein interactions with wild-type S. Thereby, a dual location of GFP, inside and outside the envelope, was observed. GFP.S was also efficiently packaged into the viral envelope, and these GFP-tagged virions retained the capacity for attachment to HBV receptor-positive cells in vitro. Together, GFP-tagged virions should be suitable to monitor HBV uptake and egress in live hepatocytes

Indoor Modelling from Slam-Based Laser Scanner: Door Detection to Envelope Reconstruction

Science.gov (United States)

Díaz-Vilariño, L.; Verbree, E.; Zlatanova, S.; Diakité, A.

2017-09-01

Updated and detailed indoor models are being increasingly demanded for various applications such as emergency management or navigational assistance. The consolidation of new portable and mobile acquisition systems has led to a higher availability of 3D point cloud data from indoors. In this work, we explore the combined use of point clouds and trajectories from SLAM-based laser scanner to automate the reconstruction of building indoors. The methodology starts by door detection, since doors represent transitions from one indoor space to other, which constitutes an initial approach about the global configuration of the point cloud into building rooms. For this purpose, the trajectory is used to create a vertical point cloud profile in which doors are detected as local minimum of vertical distances. As point cloud and trajectory are related by time stamp, this feature is used to subdivide the point cloud into subspaces according to the location of the doors. The correspondence between subspaces and building rooms is not unambiguous. One subspace always corresponds to one room, but one room is not necessarily depicted by just one subspace, for example, in case of a room containing several doors and in which the acquisition is performed in a discontinue way. The labelling problem is formulated as combinatorial approach solved as a minimum energy optimization. Once the point cloud is subdivided into building rooms, envelop (conformed by walls, ceilings and floors) is reconstructed for each space. The connectivity between spaces is included by adding the previously detected doors to the reconstructed model. The methodology is tested in a real case study.

The Effect of Mechanical Load on the Thermal Conductivity of Building Materials

Directory of Open Access Journals (Sweden)

J. Toman

2000-01-01

Full Text Available The effect of mechanical load on the thermal conductivity of building materials in the design of envelope parts of building structures is studied. A typical building material is chosen in the practical investigation of this effect, namely the cement mortar. It is concluded that in the range of hygroscopic moisture content, lower levels of mechanical load, typically up to 90 % of compressive strength (CS, are not dangerous from the point of view of worsening the designed thermal properties, but in the overhygroscopic region, the load as low as 57 % of CS may be dangerous. The higher levels of loading are found to be always significant because they lead to marked increase of thermal conductivity which is always a negative information for a building designer.

Heat Loss Measurements in Buildings Utilizing a U-value Meter

DEFF Research Database (Denmark)

Sørensen, Lars Schiøtt

Heating of buildings in Denmark accounts for approximately 40% of the entire national energy consumption. For this reason, a reduction of heat losses from building envelopes are of great importance in order to reach the Bologna CO2 emission reduction targets. Upgrading of the energy performance...... of buildings is a topic of huge global interest these years. Not only heating in the temperate and arctic regions are important, but also air conditioning and mechanical ventilation in the tropical countries contribute to an enormous energy consumption and corresponding CO2 emission. In order to establish...... the best basis for upgrading the energy performance, it is important to measure the heat losses at different locations on a building facade, in order to optimize the energy performance. The author has invented a U-value meter, enabling measurements of heat transfer coefficients. The meter has been used...

Calculation of CWKB envelope in boson and fermion productions

Indian Academy of Sciences (India)

Abstract. We present the calculation of envelope of boson and of both low- and high- mass fermion production at the end of inflation when the coherently oscillating inflatons decay into bosons and fermions. We consider three different models of inflation and use. CWKB technique to calculate the envelope to understand the ...

Evaluation of building envelopes from the viewpoint of capability of controlling thermal environment; Onnetsu kankyo chosei noryoku ni yoru kenchiku gaihi no hyoka no kokoromi

Energy Technology Data Exchange (ETDEWEB)

Umeda, K; Ono, S [Taisei Corp., Tokyo (Japan); Shukuya, M [Musashi Institute of Technology, Tokyo (Japan)

1996-10-27

The ability that architectural space improves the thermal environment in comparison with outdoor environment is called the `capability of controlling thermal environment.` As the value becomes higher, the indoor thermal environment is more improved. In this paper, the controlling capability of six building envelopes with different window systems was compared. The heat transfer in the wall and window system is approximated using a lumped mass model of heat capacity to obtain a heat balance equation and combined with the heat balance equation in indoor air for backward difference. The wall surface temperature and indoor air temperature in a calculation model are then calculated. A radiation absorption coefficient is used for mutual radiation on each wall. In the model, the adjoining room or first- and second-floor rooms were made the same in conditions as the model on the assumption that the one-side lighted office in an RC reference floor is in the non-illumination and non-airconditioning state. In summer, the controlling capability remarkably varies depending on the window system. For the window facing the south, the annual capability is more advanced than in other directions and the indoor thermal environment is improved on the average. 7 refs., 12 figs., 1 tab.

Final deactivation report on the radioisotope production Lab-C, Building 3030, at Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1997-08-01

The purpose of this report is to document the condition of Bldg. 3030 completion of deactivation activities as outlined by the Department of Energy (DOE) Office of Nuclear Materials and Facility Stabilization Program (EM-60) guidance documentation. This report outlines the activities conducted to place the facility in a safe and environmentally sound condition for transfer to DOE's Office of Environmental Restoration Program (EM-40). This report provides profile of Bldg. 3030 before and after deactivation activities. Turnover items, such as the Postdeactivation Surveillance ampersand Maintenance Plan, remaining hazardous materials, radiological controls, Safeguards and Security, QA, facility operations, and supporting documentation provided in the Office of Nuclear Materials and Facility Stabilization Program (EM-60) Turnover package are discussed. Building 3030 will require access to facilitate required S ampersand M activities to maintain the building safety envelope. Building 3030 was stabilized during deactivation so that when transferred to the EM-40 program, only a minimal S ampersand M effort would be required to maintain the building's safety envelope. Other than the minimal S ampersand M activities, the building will be unoccupied and the exterior doors locked to prevent unauthorized access. The building will be entered only for required S ampersand M. All materials have been removed from the building and the hot cell, and all utility systems, piping, and alarms have been deactivated

Final deactivation report on the radioisotope production Lab-D, Building 3031, at Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1997-08-01

The purpose of this report is to document the condition of Bldg. 3031 after completion of deactivation activities as outlined by the Department of Energy Office of Nuclear Materials and Facility Stabilization Program (EM-60) guidance documentation. This report outlines the activities conducted to place the facility in a safe and environmentally sound condition for transfer to the Department of Energy Office of Environmental Restoration (EM-40) Program. This report provides a profile of Bldg. 3031 before and after deactivation activities. Turnover items, such as the Postdeactivation Surveillance ampersand Maintenance Plan, remaining hazardous materials, radiological controls, Safeguards and Security, quality assurance, facility operations, and supporting documentation provided in the Office of Nuclear Materials and Facility Stabilization Program (EM-60) Turnover package, are discussed. Building 3031 will require access to facilitate required surveillance and maintenance activities to maintain the building safety envelope. Building 3031 was stabilized during deactivation so that when transferred to the EM-40 program, only a minimal surveillance and maintenance effort would be required to maintain the building safety envelope. Other than the minimal surveillance and maintenance activities, the building will be unoccupied and the exterior doors locked to prevent unauthorized access. The building will be entered only to perform the required surveillance and maintenance. All materials have been removed from the building and the hot cell, and all utility systems, piping, and alarms have been deactivated

ADAPTIVE BUILDING EXOSKELETONS: A biomimetic model for the rehabilitation of social housing

Directory of Open Access Journals (Sweden)

Giuliana Scuderi

2015-03-01

Full Text Available This research is an attempt to describe a new biomimetic model for the rehabilitation of social housing. In particular, the constructions built in Europe in the post Second World War period suffer of material and social degradation requiring architectural, functional and structural interventions. The analysis of the state of the art underlined the importance of the envelope in the definition of new performances and standards. Through a bio-mimicry approach, the paper shows the process leading to the definition of a building exoskeleton: a structural envelope able to solve complex sets of problems integrating different building systems. Adaptability results being a fundamental property to define an effective seismic and structural behavior but also to respond to changing user’s needs and environmental conditions. In the last part of the paper, information about feasible technologies and techniques to realize the exoskeleton are presented. Finally, the conclusions show the potentiality of the model if applied in critical contexts where intensive and diffusive interventions of recovery of social housing are needed.

Optimization of annual energy demand in office buildings under the influence of climate change in Chile

International Nuclear Information System (INIS)

Rubio-Bellido, Carlos; Pérez-Fargallo, Alexis; Pulido-Arcas, Jesús A.

2016-01-01

Numerous studies about climate change have emerged in recent years because of their potential impact on many activities of human life, amongst which, the building sector is no exception. Changes in climate conditions have a direct influence on the external conditions for buildings and, thus, on their energy demand. In this context, computer aided simulation provides handy tools that help in assessing this impact. This paper investigates climate data for future scenarios and the effect on energy demand in office buildings in Chile. This data has been generated in the 9 climatic zones that are representative of the main inhabited areas, for the years 2020, 2050 and 2080. Predictions have been produced for the acknowledged A2 ‘medium-high’ Greenhouse Gases emissions GHG scenario, pursuant the Intergovernmental Panel on Climate Change (IPCC). The effect of climate change on the energy demand for office buildings is optimized by implementing the calculation procedure of ISO-13790:2008, based on iterations of its envelope and form. As a result, this research clarifies how future climate scenarios will affect the energy demand for different types of office buildings in Chile, and how their shape and enclosure can be optimized. - Highlights: • Forecast of 9 Chilean climate zones under Greenhouse Gases Scenario A2. • Influence of envelope and form on future energy demand in office buildings. • Multiple iterations on Form Ratio (FR) and Window-to-Wall Ratio (WWR). • Optimization in early stages of design considering global warming.

High frequency vibration analysis by the complex envelope vectorization.

Science.gov (United States)

Giannini, O; Carcaterra, A; Sestieri, A

2007-06-01

The complex envelope displacement analysis (CEDA) is a procedure to solve high frequency vibration and vibro-acoustic problems, providing the envelope of the physical solution. CEDA is based on a variable transformation mapping the high frequency oscillations into signals of low frequency content and has been successfully applied to one-dimensional systems. However, the extension to plates and vibro-acoustic fields met serious difficulties so that a general revision of the theory was carried out, leading finally to a new method, the complex envelope vectorization (CEV). In this paper the CEV method is described, underlying merits and limits of the procedure, and a set of applications to vibration and vibro-acoustic problems of increasing complexity are presented.

Aspherical Dust Envelopes Around Oxygen-Rich AGB Stars

Directory of Open Access Journals (Sweden)

Kyung-Won Suh

2006-12-01

Full Text Available We model the aspherical dust envelopes around O-rich AGB stars. We perform the radiative transfer model calculations for axisymmetric dust distributions. We simulate what could be observed from the aspherical dust envelopes around O-rich AGB stars by presenting the model spectral energy distributions and images at various wavelengths for different optical depths and viewing angles. The model results are very different from the ones with spherically symmetric geometry.

Condensins Exert Force on Chromatin-Nuclear Envelope Tethers to Mediate Nucleoplasmic Reticulum Formation in Drosophila melanogaster

Science.gov (United States)

Bozler, Julianna; Nguyen, Huy Q.; Rogers, Gregory C.; Bosco, Giovanni

2014-01-01

Although the nuclear envelope is known primarily for its role as a boundary between the nucleus and cytoplasm in eukaryotes, it plays a vital and dynamic role in many cellular processes. Studies of nuclear structure have revealed tissue-specific changes in nuclear envelope architecture, suggesting that its three-dimensional structure contributes to its functionality. Despite the importance of the nuclear envelope, the factors that regulate and maintain nuclear envelope shape remain largely unexplored. The nuclear envelope makes extensive and dynamic interactions with the underlying chromatin. Given this inexorable link between chromatin and the nuclear envelope, it is possible that local and global chromatin organization reciprocally impact nuclear envelope form and function. In this study, we use Drosophila salivary glands to show that the three-dimensional structure of the nuclear envelope can be altered with condensin II-mediated chromatin condensation. Both naturally occurring and engineered chromatin-envelope interactions are sufficient to allow chromatin compaction forces to drive distortions of the nuclear envelope. Weakening of the nuclear lamina further enhanced envelope remodeling, suggesting that envelope structure is capable of counterbalancing chromatin compaction forces. Our experiments reveal that the nucleoplasmic reticulum is born of the nuclear envelope and remains dynamic in that they can be reabsorbed into the nuclear envelope. We propose a model where inner nuclear envelope-chromatin tethers allow interphase chromosome movements to change nuclear envelope morphology. Therefore, interphase chromatin compaction may be a normal mechanism that reorganizes nuclear architecture, while under pathological conditions, such as laminopathies, compaction forces may contribute to defects in nuclear morphology. PMID:25552604

Condensins exert force on chromatin-nuclear envelope tethers to mediate nucleoplasmic reticulum formation in Drosophila melanogaster.

Science.gov (United States)

Bozler, Julianna; Nguyen, Huy Q; Rogers, Gregory C; Bosco, Giovanni

2014-12-30

Although the nuclear envelope is known primarily for its role as a boundary between the nucleus and cytoplasm in eukaryotes, it plays a vital and dynamic role in many cellular processes. Studies of nuclear structure have revealed tissue-specific changes in nuclear envelope architecture, suggesting that its three-dimensional structure contributes to its functionality. Despite the importance of the nuclear envelope, the factors that regulate and maintain nuclear envelope shape remain largely unexplored. The nuclear envelope makes extensive and dynamic interactions with the underlying chromatin. Given this inexorable link between chromatin and the nuclear envelope, it is possible that local and global chromatin organization reciprocally impact nuclear envelope form and function. In this study, we use Drosophila salivary glands to show that the three-dimensional structure of the nuclear envelope can be altered with condensin II-mediated chromatin condensation. Both naturally occurring and engineered chromatin-envelope interactions are sufficient to allow chromatin compaction forces to drive distortions of the nuclear envelope. Weakening of the nuclear lamina further enhanced envelope remodeling, suggesting that envelope structure is capable of counterbalancing chromatin compaction forces. Our experiments reveal that the nucleoplasmic reticulum is born of the nuclear envelope and remains dynamic in that they can be reabsorbed into the nuclear envelope. We propose a model where inner nuclear envelope-chromatin tethers allow interphase chromosome movements to change nuclear envelope morphology. Therefore, interphase chromatin compaction may be a normal mechanism that reorganizes nuclear architecture, while under pathological conditions, such as laminopathies, compaction forces may contribute to defects in nuclear morphology. Copyright © 2015 Bozler et al.

Study on the optimum PCM melting temperature for energy savings in residential buildings worldwide

Science.gov (United States)

Saffari, M.; de Gracia, A.; Fernández, C.; Zsembinszki, G.; Cabeza, L. F.

2017-10-01

To maintain comfort conditions in residential buildings along a full year period, the use of active systems is generally required to either supply heating or cooling. The heating and cooling demands strongly depend on the climatic conditions, type of building and occupants’ behaviour. The overall annual energy consumption of the building can be reduced by the use of renewable energy sources and/or passive systems. The use of phase change materials (PCM) as passive systems in buildings enhances the thermal mass of the envelope, and reduces the indoor temperature fluctuations. As a consequence, the overall energy consumption of the building is generally lower as compared to the case when no PCM systems are used. The selection of the PCM melting temperature is a key issue to reduce the energy consumption of the buildings. The main focus of this study is to determine the optimum PCM melting temperature for passive heating and cooling according to different weather conditions. To achieve that, numerical simulations were carried out using EnergyPlus v8.4 coupled with GenOpt® v3.1.1 (a generic optimization software). A multi-family residential apartment was selected from ASHRAE Standard 90.1- 2013 prototype building model, and different climate conditions were considered to determine the optimum melting temperature (in the range from 20ºC to 26ºC) of the PCM contained in gypsum panels. The results confirm that the optimum melting temperature of the PCM strongly depends on the climatic conditions. In general, in cooling dominant climates the optimum PCM temperature is around 26ºC, while in heating dominant climates it is around 20ºC. Furthermore, the results show that an adequate selection of the PCM as passive system in building envelope can provide important energy savings for both heating dominant and cooling dominant regions.

Spectral envelope sensitivity of musical instrument sounds.

Science.gov (United States)

Gunawan, David; Sen, D

2008-01-01

It is well known that the spectral envelope is a perceptually salient attribute in musical instrument timbre perception. While a number of studies have explored discrimination thresholds for changes to the spectral envelope, the question of how sensitivity varies as a function of center frequency and bandwidth for musical instruments has yet to be addressed. In this paper a two-alternative forced-choice experiment was conducted to observe perceptual sensitivity to modifications made on trumpet, clarinet and viola sounds. The experiment involved attenuating 14 frequency bands for each instrument in order to determine discrimination thresholds as a function of center frequency and bandwidth. The results indicate that perceptual sensitivity is governed by the first few harmonics and sensitivity does not improve when extending the bandwidth any higher. However, sensitivity was found to decrease if changes were made only to the higher frequencies and continued to decrease as the distorted bandwidth was widened. The results are analyzed and discussed with respect to two other spectral envelope discrimination studies in the literature as well as what is predicted from a psychoacoustic model.

The cell envelope glycoconjugates of Mycobacterium tuberculosis

Science.gov (United States)

Angala, Shiva Kumar; Belardinelli, Juan Manuel; Huc-Claustre, Emilie; Wheat, William H.; Jackson, Mary

2015-01-01

Tuberculosis (TB) remains the second most common cause of death due to a single infectious agent. The cell envelope of Mycobacterium tuberculosis (Mtb), the causative agent of the disease in humans, is a source of unique glycoconjugates and the most distinctive feature of the biology of this organism. It is the basis of much of Mtb pathogenesis and one of the major causes of its intrinsic resistance to chemotherapeutic agents. At the same time, the unique structures of Mtb cell envelope glycoconjugates, their antigenicity and essentiality for mycobacterial growth provide opportunities for drug, vaccine, diagnostic and biomarker development, as clearly illustrated by recent advances in all of these translational aspects. This review focuses on our current understanding of the structure and biogenesis of Mtb glycoconjugates with particular emphasis on one of most intriguing and least understood aspect of the physiology of mycobacteria: the translocation of these complex macromolecules across the different layers of the cell envelope. It further reviews the rather impressive progress made in the last ten years in the discovery and development of novel inhibitors targeting their biogenesis. PMID:24915502

Mass-radius relations and core-envelope decompositions of super-Earths and sub-Neptunes

Energy Technology Data Exchange (ETDEWEB)

Howe, Alex R.; Burrows, Adam [Department of Astrophysical Sciences, Princeton University, Peyton Hall, Princeton, NJ 08544 (United States); Verne, Wesley, E-mail: arhowe@astro.princeton.edu, E-mail: burrows@astro.princeton.edu [Department of Computer Science, Princeton University, Princeton, NJ 08544 (United States)

2014-06-01

Many exoplanets have been discovered with radii of 1-4 R {sub ⊕}, between that of Earth and Neptune. A number of these are known to have densities consistent with solid compositions, while others are 'sub-Neptunes' likely to have significant H{sub 2}-He envelopes. Future surveys will no doubt significantly expand these populations. In order to understand how the measured masses and radii of such planets can inform their structures and compositions, we construct models both for solid layered planets and for planets with solid cores and gaseous envelopes, exploring a range of core masses, H{sub 2}-He envelope masses, and associated envelope entropies. For planets in the super-Earth/sub-Neptune regime for which both radius and mass are measured, we estimate how each is partitioned into a solid core and gaseous envelope, associating a specific core mass and envelope mass with a given exoplanet. We perform this decomposition for both ''Earth-like'' rock-iron cores and pure ice cores, and find that the necessary gaseous envelope masses for this important sub-class of exoplanets must range very widely from zero to many Earth masses, even for a given core mass. This result bears importantly on exoplanet formation and envelope evaporation processes.

Mass-radius relations and core-envelope decompositions of super-Earths and sub-Neptunes

International Nuclear Information System (INIS)

Howe, Alex R.; Burrows, Adam; Verne, Wesley

2014-01-01

Many exoplanets have been discovered with radii of 1-4 R ⊕ , between that of Earth and Neptune. A number of these are known to have densities consistent with solid compositions, while others are 'sub-Neptunes' likely to have significant H 2 -He envelopes. Future surveys will no doubt significantly expand these populations. In order to understand how the measured masses and radii of such planets can inform their structures and compositions, we construct models both for solid layered planets and for planets with solid cores and gaseous envelopes, exploring a range of core masses, H 2 -He envelope masses, and associated envelope entropies. For planets in the super-Earth/sub-Neptune regime for which both radius and mass are measured, we estimate how each is partitioned into a solid core and gaseous envelope, associating a specific core mass and envelope mass with a given exoplanet. We perform this decomposition for both ''Earth-like'' rock-iron cores and pure ice cores, and find that the necessary gaseous envelope masses for this important sub-class of exoplanets must range very widely from zero to many Earth masses, even for a given core mass. This result bears importantly on exoplanet formation and envelope evaporation processes.

Data on cost-optimal Nearly Zero Energy Buildings (NZEBs across Europe

Directory of Open Access Journals (Sweden)

Delia D'Agostino

2018-04-01

Full Text Available This data article refers to the research paper A model for the cost-optimal design of Nearly Zero Energy Buildings (NZEBs in representative climates across Europe [1]. The reported data deal with the design optimization of a residential building prototype located in representative European locations. The study focus on the research of cost-optimal choices and efficiency measures in new buildings depending on the climate. The data linked within this article relate to the modelled building energy consumption, renewable production, potential energy savings, and costs. Data allow to visualize energy consumption before and after the optimization, selected efficiency measures, costs and renewable production. The reduction of electricity and natural gas consumption towards the NZEB target can be visualized together with incremental and cumulative costs in each location. Further data is available about building geometry, costs, CO2 emissions, envelope, materials, lighting, appliances and systems.

Data on cost-optimal Nearly Zero Energy Buildings (NZEBs) across Europe.

Science.gov (United States)

D'Agostino, Delia; Parker, Danny

2018-04-01

This data article refers to the research paper A model for the cost-optimal design of Nearly Zero Energy Buildings (NZEBs) in representative climates across Europe [1]. The reported data deal with the design optimization of a residential building prototype located in representative European locations. The study focus on the research of cost-optimal choices and efficiency measures in new buildings depending on the climate. The data linked within this article relate to the modelled building energy consumption, renewable production, potential energy savings, and costs. Data allow to visualize energy consumption before and after the optimization, selected efficiency measures, costs and renewable production. The reduction of electricity and natural gas consumption towards the NZEB target can be visualized together with incremental and cumulative costs in each location. Further data is available about building geometry, costs, CO 2 emissions, envelope, materials, lighting, appliances and systems.

Assessment of energy efficiency options in the building sector of Lebanon

International Nuclear Information System (INIS)

Chedid, R.B.; Ghajar, R.F.

2004-01-01

This paper examines the merits of implementing energy efficiency policies in the building sector in Lebanon following the approach normally adopted in Climate Change studies. The paper first examines the impact of the energy sector on the Lebanese economy, and then assesses the feasibility of implementing suitable energy efficiency options in the building sector. For this purpose, a detailed analysis of the building sector in Lebanon is presented with emphasis on the thermal characteristics of building envelopes and the energy consuming equipment. The long-term benefits of applying energy efficiency options in the building sector are then assessed using a scenario-type analysis that compares these benefits against those of a baseline scenario that assumes no significant implementation of energy efficiency policies. Finally, feasible options are highlighted and recommendations to remove the major barriers hindering the penetration of energy efficiency options in the Lebanese market are provided

Introduction to Building Systems Performance: Houses That Work II; Period of Performance: January 2003--December 2003

Energy Technology Data Exchange (ETDEWEB)

2004-04-01

Buildings should be suited to their environments. Design and construction must be responsive to varying seismic risks, wind loads, and snow loads, as well as soil conditions, frost depth, orientation, and solar radiation. In addition, building envelopes and mechanical systems should be designed for a specific hygro-thermal regions, rain exposure, and interior climate. The Building Science Consortium (BSC) design recommendations are based on the hygro-thermal regions with reference to the annual rainfall. Local climate must be addressed if it differs significantly from the climate described for a particular design.

New build: Materials, techniques, skills and innovation

International Nuclear Information System (INIS)

Glass, Jacqueline; Dainty, Andrew R.J.; Gibb, Alistair G.F.

2008-01-01

The transition to secure, sustainable, low-energy systems will have a significant effect on the way in which we design and construct new buildings. In turn, the new buildings that are constructed will play a critical role in delivering the better performance that would be expected from such a transition. Buildings account for about half of UK carbon dioxide (CO 2 ) production. So it is urgent to ensure that energy is used efficiently in existing buildings and that new building stock is better able to cope with whatever the future holds. Most energy used in buildings goes towards heating, lighting and cooling, but a growing percentage is consumed by domestic appliances, computers and other electrical equipment. Actual energy consumption is the product of a number of factors, including individual behaviours and expectations, the energy efficiency of appliances and the building envelope. This review focuses on the third of these, the building itself, and its design and construction. It discusses the issues faced by the construction industry today, suggesting that major changes are needed relating to materials, techniques, skills and innovation. It moves on to consider future advances to 2050 and beyond, including developments in ICT, novel materials, skills and automation, servitisation (the trend for manufacturers to offer lifetime services rather than simple products), performance measurement and reporting, and resilience. We present a vision of the new build construction industry in 2050 and recommendations for policy makers, industry organisations and construction companies

Velocity structure of protostellar envelopes: gravitational collapse and rotation

International Nuclear Information System (INIS)

Belloche, Arnaud

2002-01-01

Stars form from the gravitational collapse of pre-stellar condensations in molecular clouds. The major aim of this thesis is to compare the predictions of collapse models with observations of both very young (class 0) protostars and starless condensations in millimeter molecular lines. We wish to understand what determines the masses of forming stars and whether the initial conditions have an effect on the dynamical evolution of a condensation. Using a Monte-Carlo radiative transfer code, we analyze rotation and infall spectroscopic signatures to study the velocity structure of a sample of protostellar condensations. We show that the envelope of the class 0 protostar IRAM 04191 in the Taurus molecular cloud is undergoing both extended, subsonic infall and fast, differential rotation. We propose that the inner part of the envelope is a magnetically supercritical core in the process of decoupling from the ambient cloud still supported by the magnetic field. We suggest that the kinematical properties observed for IRAM 04191 are representative of the physical conditions characterizing isolated protostars shortly after point mass formation. On the other hand, a similar study for the pre-stellar condensations of the Rho Ophiuchi proto-cluster yields mass accretion rates that are an order of magnitude higher than in IRAM 04191. This suggests that individual protostellar collapse in clusters is induced by external disturbances. Moreover, we show that the condensations do not have time to orbit significantly through the proto-cluster gas before evolving into protostars and pre-main-sequence stars. This seems inconsistent with models which resort to dynamical interactions and competitive accretion to build up a mass spectrum comparable to the stellar initial mass function. We conclude that protostellar collapse is nearly spontaneous in regions of isolated star formation such as the Taurus cloud but probably strongly induced in proto-clusters. (author) [fr

Magnified Neural Envelope Coding Predicts Deficits in Speech Perception in Noise.

Science.gov (United States)

Millman, Rebecca E; Mattys, Sven L; Gouws, André D; Prendergast, Garreth

2017-08-09

Verbal communication in noisy backgrounds is challenging. Understanding speech in background noise that fluctuates in intensity over time is particularly difficult for hearing-impaired listeners with a sensorineural hearing loss (SNHL). The reduction in fast-acting cochlear compression associated with SNHL exaggerates the perceived fluctuations in intensity in amplitude-modulated sounds. SNHL-induced changes in the coding of amplitude-modulated sounds may have a detrimental effect on the ability of SNHL listeners to understand speech in the presence of modulated background noise. To date, direct evidence for a link between magnified envelope coding and deficits in speech identification in modulated noise has been absent. Here, magnetoencephalography was used to quantify the effects of SNHL on phase locking to the temporal envelope of modulated noise (envelope coding) in human auditory cortex. Our results show that SNHL enhances the amplitude of envelope coding in posteromedial auditory cortex, whereas it enhances the fidelity of envelope coding in posteromedial and posterolateral auditory cortex. This dissociation was more evident in the right hemisphere, demonstrating functional lateralization in enhanced envelope coding in SNHL listeners. However, enhanced envelope coding was not perceptually beneficial. Our results also show that both hearing thresholds and, to a lesser extent, magnified cortical envelope coding in left posteromedial auditory cortex predict speech identification in modulated background noise. We propose a framework in which magnified envelope coding in posteromedial auditory cortex disrupts the segregation of speech from background noise, leading to deficits in speech perception in modulated background noise. SIGNIFICANCE STATEMENT People with hearing loss struggle to follow conversations in noisy environments. Background noise that fluctuates in intensity over time poses a particular challenge. Using magnetoencephalography, we demonstrate

High pressure treatment under subfreezing temperature results in drastic inactivation of enveloped and non-enveloped viruses.

Science.gov (United States)

Kishida, T; Cui, F-D; Ohgitani, E; Gao, F; Hayakawa, K; Mazda, O

2013-08-01

Some viruses are sensitive to high pressure. The freeze-pressure generation method (FPGM) applies pressure as high as 250 MPa on a substance, simply by freezing a pressure-resistant reservoir in which the substance is immersed in water. Here we examined whether the FPGM successfully inactivates herpes simplex virus type 1 (HSV-1), an enveloped DNA virus belonging to the human Herpesviridae, and encephalomyocarditis virus (EMCV), an envelope-free RNA virus belonging to the Picornaviridae. After the treatment, HSV-1 drastically reduced the ability to form plaque in Vero cells in vitro as well as to kill mice in vivo. EMCV that had been pressurized failed to proliferate in HeLa cells and induce interferon response. The results suggest that the FPGM provides a feasible procedure to inactivate a broad spectrum of viruses.

A study of some Be star envelopes

International Nuclear Information System (INIS)

Kitchen, C.R.

1976-01-01

The envelope model and emission region radius of six Be stars have been determined from 36 lines on 15 spectra taken with the Isaac Newton telescope. The results have been compared with earlier determinations to search for changes with the time. No definite evidence for such changes has been found, although there may be an indication of a change in phi Per. A re-determination of the errors involved in the method of analysis shows that these are smaller than previously estimated and range from about 9% to 35% for both envelope model and emission region radius. (Auth.)

A controlled trial of envelope colour for increasing response rates in older women.

Science.gov (United States)

Mitchell, Natasha; Hewitt, Catherine E; Torgerson, David J

2011-06-01

Postal questionnaires are widely used in health research to provide measurable outcomes in areas such as quality of life. Participants who fail to return postal questionnaires can introduce non-response bias. Previous studies within populations over the age of 65 years have shown that response rates amongst older people can be 60% or less. The current study sought to investigate whether envelope colour affected response rates in a study about the effectiveness of screening older women for osteoporosis. A total of 2803 eligible female participants aged between 70 and 85 were sent an invitation pack from their GP practice. The invitation was either in a brown or white envelope and contained a matching pre-paid reply envelope. A study questionnaire was also sent out in brown or white envelopes 1 week after consenting to participate in the trial. The overall response rate was 78%. There was little evidence of an effect of envelope colour on response to the invitation to participate in the trial (OR 1.04, 95% CI 0.87-1.24). Similarly, there was no influence of envelope colour on the number of participants returning their questionnaires (OR 0.99, 95% CI 0.60-1.63). There was weak evidence of an effect of envelope colour on the response rates of the consent process (OR 0.86, 95% CI 0.74-1.00). When we updated a recent meta-analysis with the results of this study, there was a non-statistically- significant trend for greater response rates with brown envelopes compared with white envelopes (OR 1.19, 95% CI 0.86-1.64, I2=92%). However, the results where influenced by one study and when this study was excluded the pooled estimate was 0.98 (95% CI 0.89-1.08, I2=0%). This study found no evidence to suggest envelope colour has an effect on response to participate in a trial or questionnaire returns. There is weak evidence to suggest envelope colour may affect consent into a trial.

The psychic envelopes in psychoanalytic theories of infancy.

Directory of Open Access Journals (Sweden)

Denis eMellier

2014-07-01

Full Text Available This paper aims to review the topic of psychic envelopes and to sketch the main outlines of this concept in infancy. We first explore the origins of the concept in Freud's 'protective shield' and then its development in adult psychoanalysis before going on to see how this fits in infancy with post-Bionian psychoanalysis and development. Four central notions guide this review:1 Freud's protective shield describes a barrier to protect the psychic apparatus against potentially overflowing trauma. It is a core notion which highlights a serious clinical challenge for patients for whom the shield is damaged or faulty: the risk of confusion of borders between the internal/external world, conscious/unconscious, mind/body, or self-conservation/sexuality.2 Anzieu's Skin-Ego is defined by the different senses of the body. The different layers of experienced sensation, of this body-ego, go on to form the psychic envelope. This theory contributes to our understanding of how early trauma, due to the failures of maternal care, can continue to have an impact in adult life. 3 Bick's psychic skin establishes the concept in relation to infancy. The mother’s containing functions allow a first psychic skin to develop, which then defines an infant’s psychic space and affords the infant a degree of self-containment. Houzel then conceptualized this process as a stabilization of drive forces.4 Stern's narrative envelope derives from the intersection between psychoanalysis and neuroscience. It gives us another way to conceptualise the development of pre-verbal communication. It may also pave the way for a finer distinction of different types of envelopes.Ultimately, in this review we find that psychic envelopes in infancy can be viewed from four different perspectives (economic, topographical, dynamic and genetic and recommend further investigation.

Improvement of energy performances of existing buildings by application of solar thermal systems

Directory of Open Access Journals (Sweden)

Krstić-Furundžić Aleksandra

2009-01-01

Full Text Available Improvement of energy performances of the existing buildings in the suburban settlement Konjarnik in Belgrade, by the application of solar thermal systems is the topic presented in this paper. Hypothetical models of building improvements are created to allow the benefits of applying solar thermal collectors to residential buildings in Belgrade climate conditions to be estimated. This case study presents different design variants of solar thermal collectors integrated into a multifamily building envelope. The following aspects of solar thermal systems integration are analyzed in the paper: energy, architectural, ecological and economic. The results show that in Belgrade climatic conditions significant energy savings and reduction of CO2 emissions can be obtained with the application of solar thermal collectors.

HIV-1 envelope glycoprotein

Science.gov (United States)

Caulfield, Michael; Cupo, Albert; Dean, Hansi; Hoffenberg, Simon; King, C. Richter; Klasse, P. J.; Marozsan, Andre; Moore, John P.; Sanders, Rogier W.; Ward, Andrew; Wilson, Ian; Julien, Jean-Philippe

2017-08-22

The present application relates to novel HIV-1 envelope glycoproteins, which may be utilized as HIV-1 vaccine immunogens, and antigens for crystallization, electron microscopy and other biophysical, biochemical and immunological studies for the identification of broad neutralizing antibodies. The present invention encompasses the preparation and purification of immunogenic compositions, which are formulated into the vaccines of the present invention.

Regulation proposal for voluntary energy efficiency labelling of commercial buildings

International Nuclear Information System (INIS)

Lamberts, Roberto; Goulart, Solange; Carlo, Joyce; Westphal, Fernando

2006-01-01

Despite of Brazil not being between the major world energy consumers, the consumption of electricity has significantly increased in the late years. The National Energy Balance of 2005, published by the Brazilian Ministry of Energy, showed an increasing of the participation of electricity in the final energy consumption of 15.7% in 2002 to 16.2% in 2004. Initially, a brief review of the initiatives taken by Brazilian Government aiming to limit and control the energy consumption in buildings is presented. Then, the regulation proposal containing the technical requirements to classify the energy efficiency level of buildings is shown. The purpose of this voluntary regulation is to provide conditions to certify the energy efficiency level of Brazilian buildings (commercial and public). It specifies the methods for energy efficiency rating of buildings and includes requirements to attend energy conservation measures in three main issues: lighting system; air conditioning system and envelope. The regulation applies to large buildings (minimum total area of 500 m 2 or when the energy demand is greater than or equal to 2,3 kV, including: Conditioned buildings; Partially conditioned buildings and Naturally ventilated buildings. (author)

Handbook on data envelopment analysis

CERN Document Server

Cooper, William W; Zhu, Joe

2011-01-01

Focusing on extensively used Data Envelopment Analysis topics, this volume aims to both describe the state of the field and extend the frontier of DEA research. New chapters include DEA models for DMUs, network DEA, models for supply chain operations and applications, and new developments.

Monte Carlo investigation of the low-dose envelope from scanned proton pencil beams

International Nuclear Information System (INIS)

Sawakuchi, Gabriel O; Titt, Uwe; Mirkovic, Dragan; Ciangaru, George; Zhu, X Ronald; Sahoo, Narayan; Gillin, Michael T; Mohan, Radhe

2010-01-01

Scanned proton pencil beams carry a low-dose envelope that extends several centimeters from the individual beam's central axis. Thus, the total delivered dose depends on the size of the target volume and the corresponding number and intensity of beams necessary to cover the target volume uniformly. This dependence must be considered in dose calculation algorithms used by treatment planning systems. In this work, we investigated the sources of particles contributing to the low-dose envelope using the Monte Carlo technique. We used a validated model of our institution's scanning beam line to determine the contributions to the low-dose envelope from secondary particles created in a water phantom and particles scattered in beam line components. Our results suggested that, for high-energy beams, secondary particles produced by nuclear interactions in the water phantom are the major contributors to the low-dose envelope. For low-energy beams, the low-dose envelope is dominated by particles undergoing multiple Coulomb scattering in the beam line components and water phantom. Clearly, in the latter situation, the low-dose envelope depends directly on beam line design features. Finally, we investigated the dosimetric consequences of the low-dose envelope. Our results showed that if not modeled properly the low-dose envelope may cause clinically relevant dose disturbance in the target volume. This work suggested that this low-dose envelope is beam line specific for low-energy beams, should be thoroughly experimentally characterized and validated during commissioning of the treatment planning system, and therefore is of great concern for accurate delivery of proton scanning beam doses.

Dynamical model for the dusty envelope around the symbiotic nova PU Vulpeculae

International Nuclear Information System (INIS)

Men'shchikov, A.B.; Tutukov, A.V.; Shustov, B.M.; Ergma, E.V.

1985-01-01

An evolutionary model for PU Vul, Object Kuwano--Honda, indicates that the deep 1980--1981 minimum may have resulted from detachment of a dust envelope. The envelope ejection process and the changes in the infrared spectrum are studied numerically; evidently the envelope departs strongly from spherical symmetry. The bluing observed at minimum light might have been due to dissipation of shock energy

Semiparametric Power Envelopes for Tests of the Unit Root Hypothesis

DEFF Research Database (Denmark)

Jansson, Michael

This paper derives asymptotic power envelopes for tests of the unit root hypothesis in a zero-mean AR(1) model. The power envelopes are derived using the limits of experiments approach and are semiparametric in the sense that the underlying error distribution is treated as an unknown...

The influence of opening windows and doors on the natural ventilation rate of a residential building

Science.gov (United States)

An analysis of air exchange rates due to intentional window and door openings in a research test house located in a residential environment is presented. These data inform the development of ventilation rate control strategies as building envelopes are tightened to improve the e...

Final deactivation project report on the High Radiation Level Analytical Facility, Building 3019B at Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1997-09-01

The purpose of this report is to document the condition of the High Radiation Level Analytical Facility (Building 3019B) at Oak Ridge National Laboratory (ORNL) after completion of deactivation activities. This report identifies the activities conducted to place the facility in a safe and environmentally sound condition prior to transfer to the Environmental Restoration EM-40 Program. This document provides a history and description of the facility prior to the commencement of deactivation activities and documents the condition of the building after completion of all deactivation activities. Turnover items, such as the Post-Deactivation Surveillance and Maintenance (S ampersand M) Plan, remaining hazardous materials inventory, radiological controls, safeguards and security, quality assurance, facility operations, and supporting documentation provided in the Nuclear Material and Facility Stabilization (EM-60) Turnover package are discussed. Building 3019B will require access to perform required S ampersand M activities to maintain the building safety envelope. Building 3019B was stabilized during deactivation so that when transferred to the EM-40 Program, only a minimal S ampersand M effort would be required to maintain the building safety envelope. Other than the minimal S ampersand M activities the building will be unoccupied and the exterior doors locked to prevent unauthorized access. The building will be entered only to perform the required S ampersand M until decommissioning activities begin

Final deactivation project report on the High Radiation Level Analytical Facility, Building 3019B at Oak Ridge National Laboratory, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-09-01

The purpose of this report is to document the condition of the High Radiation Level Analytical Facility (Building 3019B) at Oak Ridge National Laboratory (ORNL) after completion of deactivation activities. This report identifies the activities conducted to place the facility in a safe and environmentally sound condition prior to transfer to the Environmental Restoration EM-40 Program. This document provides a history and description of the facility prior to the commencement of deactivation activities and documents the condition of the building after completion of all deactivation activities. Turnover items, such as the Post-Deactivation Surveillance and Maintenance (S&M) Plan, remaining hazardous materials inventory, radiological controls, safeguards and security, quality assurance, facility operations, and supporting documentation provided in the Nuclear Material and Facility Stabilization (EM-60) Turnover package are discussed. Building 3019B will require access to perform required S&M activities to maintain the building safety envelope. Building 3019B was stabilized during deactivation so that when transferred to the EM-40 Program, only a minimal S&M effort would be required to maintain the building safety envelope. Other than the minimal S&M activities the building will be unoccupied and the exterior doors locked to prevent unauthorized access. The building will be entered only to perform the required S&M until decommissioning activities begin.

Synthesis and transfer of galactolipids in the chloroplast envelope membranes of Arabidopsis thaliana.

Science.gov (United States)

Kelly, Amélie A; Kalisch, Barbara; Hölzl, Georg; Schulze, Sandra; Thiele, Juliane; Melzer, Michael; Roston, Rebecca L; Benning, Christoph; Dörmann, Peter

2016-09-20

Galactolipids [monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG)] are the hallmark lipids of photosynthetic membranes. The galactolipid synthases MGD1 and DGD1 catalyze consecutive galactosyltransfer reactions but localize to the inner and outer chloroplast envelopes, respectively, necessitating intermembrane lipid transfer. Here we show that the N-terminal sequence of DGD1 (NDGD1) is required for galactolipid transfer between the envelopes. Different diglycosyllipid synthases (DGD1, DGD2, and Chloroflexus glucosyltransferase) were introduced into the dgd1-1 mutant of Arabidopsis in fusion with N-terminal extensions (NDGD1 and NDGD2) targeting to the outer envelope. Reconstruction of DGDG synthesis in the outer envelope membrane was observed only with diglycosyllipid synthase fusion proteins carrying NDGD1, indicating that NDGD1 enables galactolipid translocation between envelopes. NDGD1 binds to phosphatidic acid (PA) in membranes and mediates PA-dependent membrane fusion in vitro. These findings provide a mechanism for the sorting and selective channeling of lipid precursors between the galactolipid pools of the two envelope membranes.

Algae façade as green building method: application of algae as a method to meet the green building regulation

Science.gov (United States)

Poerbo, Heru W.; Martokusumo, Widjaja; Donny Koerniawan, M.; Aulia Ardiani, Nissa; Krisanti, Susan

2017-12-01

The Local Government of Bandung city has stipulated a Green Building regulation through the Peraturan Walikota Number 1023/2016. Signed by the mayor in October 2016, Bandung became the first city in Indonesia that put green building as mandatory requirement in the building permit (IMB) process. Green Building regulation is intended to have more efficient consumption of energy and water, improved indoor air quality, management of liquid and solid waste etc. This objective is attained through various design method in building envelope, ventilation and air conditioning system, lighting, indoor transportation system, and electrical system. To minimize energy consumption of buildings that have large openings, sun shading device is often utilized together with low-E glass panes. For buildings in hot humid tropical climate, this method reduces indoor air temperature and thus requires less energy for air conditioning. Indoor air quality is often done by monitoring the carbon dioxide levels. Application of algae as part of building system façade has recently been introduced as replacement of large glass surface in the building façade. Algae are not yet included in the green building regulation because it is relatively new. The research will investigate, with the help of the modelling process and extensive literature, how effective is the implementation of algae in building façade to reduce energy consumption and improve its indoor air quality. This paper is written based on the design of ITB Innovation Park as an ongoing architectural design-based research how the algae-integrated building façade affects the energy consumption.

INDOOR MODELLING FROM SLAM-BASED LASER SCANNER: DOOR DETECTION TO ENVELOPE RECONSTRUCTION

Directory of Open Access Journals (Sweden)

L. Díaz-Vilariño

2017-09-01

Full Text Available Updated and detailed indoor models are being increasingly demanded for various applications such as emergency management or navigational assistance. The consolidation of new portable and mobile acquisition systems has led to a higher availability of 3D point cloud data from indoors. In this work, we explore the combined use of point clouds and trajectories from SLAM-based laser scanner to automate the reconstruction of building indoors. The methodology starts by door detection, since doors represent transitions from one indoor space to other, which constitutes an initial approach about the global configuration of the point cloud into building rooms. For this purpose, the trajectory is used to create a vertical point cloud profile in which doors are detected as local minimum of vertical distances. As point cloud and trajectory are related by time stamp, this feature is used to subdivide the point cloud into subspaces according to the location of the doors. The correspondence between subspaces and building rooms is not unambiguous. One subspace always corresponds to one room, but one room is not necessarily depicted by just one subspace, for example, in case of a room containing several doors and in which the acquisition is performed in a discontinue way. The labelling problem is formulated as combinatorial approach solved as a minimum energy optimization. Once the point cloud is subdivided into building rooms, envelop (conformed by walls, ceilings and floors is reconstructed for each space. The connectivity between spaces is included by adding the previously detected doors to the reconstructed model. The methodology is tested in a real case study.

Envelope proteins of bovine herpesvirus 1: immunological and biochemical studies

International Nuclear Information System (INIS)

Rodriguez Roque, L.L.

1986-01-01

The authors studied immunological and biochemical properties of the bovid herpesvirus 1 (BHV-1) envelope proteins in order to understand the pathogenesis of BHV-1 infection and to provide basic information for the production of effective subunit vaccines against BHV-1. Ten glycoproteins MW 180, 150, 130, 115, 97, 77, 74, 64, 55, and 45 kilodaltons (K), and a single non-glycosylated 108 K protein were quantitatively removed from purified BHV-1 virions by detergent treatment. These glycoproteins were present on the virion envelope and on the surface of BHV-1 infected cells. The quantitative removal from virions by treatment with nonionic detergents and their presence on the surface of infected cells indicate that 180/97, 150/77, and 130/74/55 K are major components of the BHV-1 envelope and are also the targets of virus neutralizing humoral immune response. Envelope glycoproteins of herpes simplex type 1 (HSV-1) bind immunoglobulin by the Fc end and it is suggested this may increase pathogenicity of this virus. They searched for a similar function in BVH-1 by measuring the ability of BHV-1 infected cells and viral envelope proteins to bind radiolabelled rabbit and bovine IgG. Binding activity for rabbit IgG or bovine IgG-Fc could not be demonstrated by BHV-1 infected MDBK cells, whereas, MDBK cells infected with HSV-1 bound rabbit IgG and bovine IgG-Fc. None of the three major envelope proteins of BHV-1 bound to rabbit or bovine IgG. The results of this study indicate that BHV-1, unlike some other herpesviruses, lack Fc binding activity

Air pollutant penetration through airflow leaks into buildings

Energy Technology Data Exchange (ETDEWEB)

Liu, De-Ling [Univ. of California, Berkeley, CA (United States)

2002-01-01

The penetration of ambient air pollutants into the indoor environment is of concern owing to several factors: (1) epidemiological studies have shown a strong association between ambient fine particulate pollution and elevated risk of human mortality; (2) people spend most of their time in indoor environments; and (3) most information about air pollutant concentration is only available from ambient routine monitoring networks. A good understanding of ambient air pollutant transport from source to receptor requires knowledge about pollutant penetration across building envelopes. Therefore, it is essential to gain insight into particle penetration in infiltrating air and the factors that affect it in order to assess human exposure more accurately, and to further prevent adverse human health effects from ambient particulate pollution. In this dissertation, the understanding of air pollutant infiltration across leaks in the building envelope was advanced by performing modeling predictions as well as experimental investigations. The modeling analyses quantified the extent of airborne particle and reactive gas (e.g., ozone) penetration through building cracks and wall cavities using engineering analysis that incorporates existing information on building leakage characteristics, knowledge of pollutant transport processes, as well as pollutant-surface interactions. Particle penetration is primarily governed by particle diameter and by the smallest dimension of the building cracks. Particles of 0.1-1 μm are predicted to have the highest penetration efficiency, nearly unity for crack heights of 0.25 mm or higher, assuming a pressure differential of 4 Pa or greater and a flow path length of 3 cm or less. Supermicron and ultrafine particles (less than 0.1 μm) are readily deposited on crack surfaces by means of gravitational settling and Brownian diffusion, respectively. The fraction of ozone penetration through building leaks could vary widely, depending significantly on its

Thermal performance envelopes for MHTGRs - Reliability by design

International Nuclear Information System (INIS)

Etzel, K.T.; Howard, W.W.; Zgliczynski, J.

1992-01-01

Thermal performance envelopes are used to specify steady-state design requirements for the systems of the modular high-temperature gas-cooled reactor (MHTGR) to maximize plant performance reliability with optimized design. The thermal performance envelopes are constructed around the expected operating point to account for uncertainties in actual plant as-built parameters and plant operation. The components are then designed to perform successfully at all points within the envelope. As a result, plant reliability is maximized by accounting for component thermal performance variation in the design. The design is optimized by providing a means to determine required margins in a disciplined and visible fashion. This is accomplished by coordinating these requirements with the various system and component designers in the early stages of the design, applying the principles of total quality management. The design is challenged by the more complex requirements associated with a range of operating conditions, but in return, high probability of delivering reliable performance throughout the plant life is ensured

Efficiency of the building societies in the Czech Republic

Directory of Open Access Journals (Sweden)

Lukáš Leksovský

2011-01-01

Full Text Available This paper is the first attempt to analyze efficiency of building societies in the Czech Republic. We apply non-parametric method Data Envelopment Analysis on data from all building societies in the sector over the period 2002–2008. Having deposits received and administrative expenses as inputs and volume of loans disbursed as output we estimate efficiency scores of all individual building societies as well as calculate the average efficiency in the industry. For this purpose we use two alternative models that allows for constant and variable returns of scale respectively. The results suggest that there is no significant improvement in efficiency of building societies during the estimation period. Furthermore, most of the building societies have not been operating at appropriate size. We also found that Českomoravská stavební spořitelna, a. s. was the most efficient building society in the Czech Republic according to the both models applied. In order to increase efficiency, we suggest reduction in the number of external employees and agents or increase of their productivity, more sophisticated products that can outperform the standard services and effective response to changes in the legislature.

Radio Imaging of Envelopes of Evolved Stars

Science.gov (United States)

Cotton, Bill

2018-04-01

This talk will cover imaging of stellar envelopes using radio VLBI techniques; special attention will be paid to the technical differences between radio and optical/IR interferomery. Radio heterodyne receivers allow a straightforward way to derive spectral cubes and full polarization observations. Milliarcsecond resolution of very bright, i.e. non thermal, emission of molecular masers in the envelopes of evolved stars can be achieved using VLBI techniques with baselines of thousands of km. Emission from SiO, H2O and OH masers are commonly seen at increasing distance from the photosphere. The very narrow maser lines allow accurate measurements of the velocity field within the emitting region.

Inability of keratinocytes lacking their specific transglutaminase to form cross-linked envelopes: Absence of envelopes as a simple diagnostic test for lamellar ichthyosis

OpenAIRE

Jeon, Saewha; Djian, Philippe; Green, Howard

1998-01-01

Epidermal keratinocytes, late in their terminal differentiation, form cross-linked envelopes resistant to ionic detergent and reducing agent. Because the cross-linking process is catalyzed by the keratinocyte transglutaminase, the absence of active transglutaminase should result in failure of the keratinocyte to form a cross-linked envelope. Three keratinocyte strains bearing mutations in the keratinocyte transglutaminase were examined: two contained no detectable transglutaminase mRNA and no...

Enveloping algebras of Lie groups with descrete series

International Nuclear Information System (INIS)

Nguyen huu Anh; Vuong manh Son

1990-09-01

In this article we shall prove that the enveloping algebra of the Lie algebra of some unimodular Lie group having discrete series, when localized at some element of the center, is isomorphic to the tensor product of a Weyl algebra over the ring of Laurent polynomials of one variable and the enveloping algebra of some reductive Lie algebra. In particular, it will be proved that the Lie algebra of a unimodular solvable Lie group having discrete series satisfies the Gelfand-Kirillov conjecture. (author). 6 refs

A study on building performance analysis for energy retrofit of existing industrial facilities

International Nuclear Information System (INIS)

Gourlis, Georgios; Kovacic, Iva

2016-01-01

Highlights: • Thermal simulation of a historical industrial hall with limited data availability. • Considering waste heat from machinery after measuring production fluctuations. • Test of retrofit alternatives for roof and skylights. • Results indicate a significant reduction in heating energy demand up to 52%. • After retrofit naturally ventilated hall can achieve thermal comfort in summer. - Abstract: Due to the strengthening of regulations and codes on building energy performance, as well as with the application of national legislations regarding energy management and efficiency, existing industrial facilities are using thermal refurbishment and renovation as impetus for increasing their overall energy efficiency. This paper analyzes a building envelope refurbishment for a case study of an existing historical industrial facility. Critical parameters affecting energy performance of industrial buildings were identified by reviewing relevant literate. Two retrofit scenarios were developed and dynamic thermal simulation using EnergyPlus was implemented to evaluate the potential for improvement. Thereby the impact of interior loads was considered, determined by measurements conducted on factory machines, occupancy and lighting operation patterns. However, information regarding constructions of the existing facility and installed technical building services is limited. There is also uncertainty in the quantification of natural ventilation air change rate for such buildings. To overcome these limitations a study of various material databases was carried out, in order to assess data for building envelope composition. Input values for missing data were provided based on literature, allowing a fair comparison between refurbishment alternatives. Simulation results showed that the heating demand of the facility could be reduced up to 52%, indicating a significant potential for energy savings. Beyond that, thermal performance against summer overheating also

Neural encoding of the speech envelope by children with developmental dyslexia.

Science.gov (United States)

Power, Alan J; Colling, Lincoln J; Mead, Natasha; Barnes, Lisa; Goswami, Usha

2016-09-01

Developmental dyslexia is consistently associated with difficulties in processing phonology (linguistic sound structure) across languages. One view is that dyslexia is characterised by a cognitive impairment in the "phonological representation" of word forms, which arises long before the child presents with a reading problem. Here we investigate a possible neural basis for developmental phonological impairments. We assess the neural quality of speech encoding in children with dyslexia by measuring the accuracy of low-frequency speech envelope encoding using EEG. We tested children with dyslexia and chronological age-matched (CA) and reading-level matched (RL) younger children. Participants listened to semantically-unpredictable sentences in a word report task. The sentences were noise-vocoded to increase reliance on envelope cues. Envelope reconstruction for envelopes between 0 and 10Hz showed that the children with dyslexia had significantly poorer speech encoding in the 0-2Hz band compared to both CA and RL controls. These data suggest that impaired neural encoding of low frequency speech envelopes, related to speech prosody, may underpin the phonological deficit that causes dyslexia across languages. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Building envelope design for renewal of air by natural ventilation in moderate climates. Proposition of a designing methodology; Conception des enveloppes de batiments pour le renouvellement d'air par ventilation naturelle en climats temperes. Proposition d'une methodologie de conception

Energy Technology Data Exchange (ETDEWEB)

Mansouri, Y.

2003-12-01

The subject of this research is to produce methods and methodological tools for the architects to support the integration of natural ventilation systems in the building envelope design. Our research is situated to the interface between the architectural practice and the physical research on natural ventilation. We are interested in phenomena that can influence or force the strategy of ventilation. A morphological analysis of naturally ventilated buildings concerning the integration modes of natural ventilation systems is done permitting US to propose a typology and a topology of ventilation systems. We define criteria in relation to the thermal comfort, to the quality of air and the economy of energy to assess air renewal techniques. In complement of the sizing tool, we elaborate a methodology of conception for the integration of passives ventilation systems. Design guidelines permit US to conclude on an effective natural ventilation system which is well adapted to collective habitat. (author)

Envelope correlation in (N, N) MIMO antenna array from scattering parameters

DEFF Research Database (Denmark)

Thaysen, Jesper; Jakobsen, Kaj Bjarne

2006-01-01

the envelope correlation coefficient. This approach has the advantage that it does not require knowledge of the antenna radiation pattern. Numerical data that include conductor and permittivity loss are shown to validate the approach. Using the scattering parameters for calculating the envelope correlation......A simple closed-form equation to calculate the envelope correlation between any two receiver or transmitter antennas in a multi-input multi-output (MIMO) system of an arbitrary number of elements is derived. The equation uses the scattering parameters obtained at the antenna feed point to calculate...

Enveloped virus flocculation and removal in osmolyte solutions.

Science.gov (United States)

Gencoglu, Maria F; Heldt, Caryn L

2015-07-20

Our ability to reduce infectious disease burden throughout the world has been greatly improved by the creation of vaccines. However, worldwide immunization rates are low. The two most likely reasons are the lack of sufficient distribution in underdeveloped countries and the high cost of vaccine products. The high costs are due to the difficulties of manufacturing individual vaccine products with specialized purification trains. In this study, we propose to use virus flocculation in osmolytes, followed by microfiltration, as an alternative vaccine purification operation. In our previous work, we demonstrated that osmolytes preferentially flocculate a non-enveloped virus, porcine parvovirus (PPV). In this work we show that osmolytes flocculate the enveloped virus, Sindbis virus heat resistant strain (SVHR), and demonstrate a >80% removal with a 0.2 μm microfilter membrane while leaving proteins in solution. The best osmolytes were tested for their ability to flocculate SVHR at different concentrations, pH and ionic strengths. Our best removal was 98% of SVHR in 0.3M mannitol at a pH of 5. We propose that osmolytes are able to flocculate hydrophobic non-enveloped and enveloped virus particles by the reduction of the hydration layer around the particles, which stimulates virus aggregation. Now that we have demonstrated that protecting osmolytes flocculate viruses, this method has the potential to be a future platform purification process for vaccines. Copyright © 2015 Elsevier B.V. All rights reserved.

Multi-layered breathing architectural envelope

DEFF Research Database (Denmark)

Lund Larsen, Andreas; Foged, Isak Worre; Jensen, Rasmus Lund

2014-01-01

A multi layered breathing envelope is developed as a method of natural ventilation. The two main layers consist of mineral wool and air permeable concrete. The mineral wool works as a dynamic insulation and the permeable concrete as a heat recovery system with a high thermal mass for heat storage...

Building Integrated Photovoltaics - A State-of-the-Art Review, Future Research Opportunities and Large-Scale Experimental Wind-Driven Rain Exposure Investigations

OpenAIRE

Breivik, Christer

2012-01-01

This work consists of three scientific journal articles on the subject building integrated photovoltaics (BIPVs), and was initiated by a student project work which consisted of a major revision and extension of an article on BIPVs (appendix A). BIPVs are photovoltaic materials that replace conventional building materials in parts of the building envelopes, such as the roof covering or facades. BIPV systems may represent a powerful and versatile tool for achieving the ever increasing demand fo...

Stability of an expanding cylindrical plasma envelope: Rayleigh--Taylor instability

International Nuclear Information System (INIS)

Han, S.J.

1982-01-01

The stability of a cylindrically symmetric plasma envelope driven outward by blast waves is considered. The plasma fluid is assumed to be a compressible, isentropic gas describable as an ideal gas ( p = arho/sup γ/, γ>1). The stability problem of such an envelope undergoing self-similar motion is solved by considering the initial-value problem. It is shown that in the early phase of an expansion, the envelope is unstable to Rayleigh--Taylor modes which develop at the inner surface. In the later phase of the expansion, the Rayleigh--Taylor modes are weakened due to the geometrical divergence effect. The implications of the time-dependent behavior of the Rayleigh--Taylor instability for plasma switches are discussed

Envelope method for background elimination from X-ray fluorescence spectra

International Nuclear Information System (INIS)

Monakhov, V.V.; Naumenko, P.A.; Chashinskaya, O.A.

2006-01-01

The influence of the background noise caused by Bremsstrahlung on the accuracy of the envelope method at x-ray fluorescence spectra processing is studied. This is carried out by the example of model spectra at different forms of Bremsstrahlung noise as well as at the presence of background noise in spectra. The interpolation by parabolic splines is used for the estimation of the error of the envelope method for the elimination of continuos background noise. It is found out that the error of the proposed method constitutes decimal parts of percent. It is shown that the envelope method is the effective technique for the elimination of the continuous Bremsstrahlung from x-ray fluorescence spectra of the first order [ru

Solar building construction - new technologies; Solares Bauen - Neue Technologien fuer Gebaeude

Energy Technology Data Exchange (ETDEWEB)

Luther, J.; Voss, K.; Wittwer, V. [Fraunhofer-Inst. fuer Solare Energiesysteme, Freiburg (Germany). Abt. ``Thermische und Optische Systeme``

1998-02-01

There is an increasing demand for integrated building concepts in order to reduce energy consumption. Building design, construction and heating, ventilation and air-conditioning (HVAC) technology are decisive in this respect. Thus, an essentially higher energy efficiency is achieved and solar energy becomes the main energy source. An `active building envelope` assumes the task of controlling the energy flows between inside and outside. This paper reports on new components, system concepts and planning tools for solar building. (orig.) [Deutsch] Fuer zukuenftige Bauten werden in hohem Masse Forderungen nach integrierten Konzepten zur Begrenzung des Energieverbrauchs gestellt. Gestalt, Konstruktion und Klimatechnik sind dabei massgebliche Einflussfaktoren. Hierdurch wird eine wesentlich hoehere Energieeffizienz erzielt und Solarenergie kann die uebrigen Energiequellen zurueckdraengen. Eine `aktive Gebaeudehuelle` uebernimmt die Aufgabe, den Energiefluss zwischen Innen und Aussen zu steuern. Der Beitrag berichtet ueber neue Komponenten, Systemkonzepte und Planungswerkzeuge fuer das Solare Bauen. (orig.)

New developments in illumination, heating and cooling technologies for energy-efficient buildings

International Nuclear Information System (INIS)

Han, H.J.; Jeon, Y.I.; Lim, S.H.; Kim, W.W.; Chen, K.

2010-01-01

This paper gives a concise review of new designs and developments of illumination, heating and air-conditioning systems and technologies for energy-efficient buildings. Important breakthroughs in these areas include high-efficiency and/or reduced cost solar system components, LED lamps, smart windows, computer-controlled illumination systems, compact combined heat-power generation systems, and so on. To take advantage of these new technologies, hybrid or cascade energy systems have been proposed and/or investigated. A survey of innovative architectural and building envelope designs that have the potential to considerably reduce the illumination and heating and cooling costs for office buildings and residential houses is also included in the review. In addition, new designs and ideas that can be easily implemented to improve the energy efficiency and/or reduce greenhouse gas emissions and environmental impacts of new or existing buildings are proposed and discussed.

Methodology developed for the energy-productive diagnosis and evaluation in health buildings

Energy Technology Data Exchange (ETDEWEB)

Martini, I.; Discoli, C.; Rosenfeld, E. [Instituto de Estudios del Habitat (IDEHAB), Facultad de Arquitectura y Urbanismo, Universidad Nacional de La Plata, La Plata, Buenos Aires (Argentina)

2007-07-01

The public health network in Argentina consists of a wide variety of buildings presenting a complex system of services and structures. In order to modulate and study the energy behaviour of each type of health facility, a database of Energy-Productive Building Modules (Modulos Edilicios Energeticos Productivos: MEEP) was built. This involved evaluating the interactions among physical spaces, building envelope, infrastructure, and equipment usage with the energy consumption, for each specialty service provided in the most common buildings present in the health service network. The MEEP database enables investigators to: (i) Obtain detailed information on each facility. (ii) Identify variables critical to an energy consumption perspective. (iii) Detect areas of over consumption and/or inadequate infrastructure. (iv) Gather essential reference material for the design of health facilities and other similar sectors. The information of each MEEP can be summarized in typological charts. (author)

Renewable building energy systems and passive human comfort solutions

Energy Technology Data Exchange (ETDEWEB)

Omer, Abdeen Mustafa [17 Juniper Court, Forest Road West, Nottingham NG7 4EU (United Kingdom)

2008-08-15

With environmental protection posing as the number one global problem, man has no choice but to reduce his energy consumption. One way to accomplish this is to resort to passive and low-energy systems to maintain thermal comfort in buildings. The conventional and modern designs of wind towers can successfully be used in hot arid regions to maintain thermal comfort (with or without the use of ceiling fans) during all hours of the cooling season, or a fraction of it. Climatic design is one of the best approaches to reduce the energy cost in buildings. Proper design is the first step of defence against the stress of the climate. Buildings should be designed according to the climate of the site, reducing the need for mechanical heating or cooling. Hence maximum natural energy can be used for creating a pleasant environment inside the built envelope. Technology and industry progress in the last decade diffused electronic and informatics' devices in many human activities, and also in building construction. The utilisation and operating opportunities components, increase the reduction of heat losses by varying the thermal insulation, optimise the lighting distribution with louver screens and operate mechanical ventilation for coolness in indoor spaces. In addition to these parameters the intelligent envelope can act for security control and became an important part of the building domotic revolution. Application of simple passive cooling measure is effective in reducing the cooling load of buildings in hot and humid climates. Fourty-three percent reductions can be achieved using a combination of well-established technologies such as glazing, shading, insulation, and natural ventilation. More advanced passive cooling techniques such as roof pond, dynamic insulation, and evaporative water jacket need to be considered more closely. The building sector is a major consumer of both energy and materials worldwide, and that consumption is increasing. Most industrialised

Modeling of Heat Transfer in Rooms in the Modelica "Buildings" Library

Energy Technology Data Exchange (ETDEWEB)

Wetter, Michael [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Zuo, Wangda [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Nouidui, Thierry Stephane [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2011-11-01

This paper describes the implementation of the room heat transfer model in the free open-source Modelica \\Buildings" library. The model can be used as a single room or to compose a multizone building model. We discuss how the model is decomposed into submodels for the individual heat transfer phenomena. We also discuss the main physical assumptions. The room model can be parameterized to use different modeling assumptions, leading to linear or non-linear differential algebraic systems of equations. We present numerical experiments that show how these assumptions affect computing time and accuracy for selected cases of the ANSI/ASHRAE Standard 140- 2007 envelop validation tests.

Design and evaluation of a Flight Envelope Protection haptic feedback system

NARCIS (Netherlands)

Ellerbroek, J.; Rodriguez Martin, M.J.M.; Lombaerts, T; van Paassen, M.M.; Mulder, M.

2016-01-01

This paper describes the design and evaluation of a shared control, haptic feedback system to communicate Flight Envelope Protection System intent. The concept uses a combination of stiffness feedback and vibration to communicate proximity of the aircraft state to flight envelope boundaries. In

Assessing the accuracy of a simplified building energy simulation model using BESTEST : the case study of Brazilian regulation

NARCIS (Netherlands)

Melo, A.P.; Cóstola, D.; Lamberts, R.; Hensen, J.L.M.

2012-01-01

This paper reports the use of an internationally recognized validation and diagnostics procedure to test the fidelity of a simplified calculation method. The case study is the simplified model for calculation of energy performance of building envelopes, introduced by the Brazilian regulation for

Economic assessment of energy storage for load shifting in Positive Energy Building

DEFF Research Database (Denmark)

Dumont, Olivier; Carmo, Carolina; Georges, Emeline

2016-01-01

Net Zero Energy Buildings (NZEB) and Positive Energy Buildings (PEB) are gaining more and more interest. In this paper, the impact of the integration of a battery in a positive energy building is assessed in order to increase its self-consumption of electricity. Parametric studies are carried out......-in tariff and a 5 kWh battery. Finally, simple correlations (based on the feed-in tariff, the annual electrical consumption and production) to predict the optimal size of battery and the lowest payback period are proposed.......Net Zero Energy Buildings (NZEB) and Positive Energy Buildings (PEB) are gaining more and more interest. In this paper, the impact of the integration of a battery in a positive energy building is assessed in order to increase its self-consumption of electricity. Parametric studies are carried out...... by varying the building envelope characteristics, the power supply system, the climate, the lightning and appliances profiles, the roof tilt, the battery size and the electricity tariffs, leading to 3200 cases. The analysis is performed on an annual basis in terms of self-consumption rate, shifted energy...

Circumstellar envelopes of Cepheids: a possible bias affecting the distance scale?

Science.gov (United States)

Kervella, Pierre; Gallenne, Alexandre; Mérand, Antoine

2013-02-01

Circumstellar envelopes (CSEs) have been detected around many Cepheids, first based on long-baseline interferometry, and now also using other observing techniques. These envelopes are particularly interesting for two reasons: their presence could impact the Cepheid distance scale, and they may be valuable tracers of stellar mass loss. Here we focus on their potential impact on the calibration of the Cepheid distance scale. We consider the photometric contribution of the envelopes in the visible, near-, and thermal-infrared domains. We conclude that the impact of CSEs on the apparent luminosities of Cepheids is negligible at visible wavelengths and generally weak (case. Overall, the contribution of CSEs to the usual period-luminosity relations (from the visible to the K band) is mostly negligible. They could affect calibrations at longer wavelengths, although the presence of envelopes may have been partially taken into account in the existing empirical calibrations.

Application of Prefabricated Panels for the Energy Retrofit of Portuguese Residential Buildings Facades: A Case Study

Directory of Open Access Journals (Sweden)

Sousa J.

2013-09-01

Full Text Available This article aims to evaluate the potential application of prefabricated panels in energy retrofit of facades in the Portuguese building stock. The fundamentals of this study were part of Annex 50, which was an international ECBCS IEA project, with the purpose of developing an innovative concept of building renovation for the most representative buildings based on prefabricated systems. To analyze the potential application of energy retrofit using prefabricated panels, was important to know the reality of the existing building stock and its morphology. To know the reality of the building stock, an analysis was done based on the existing statistical data and to find the most representative residential buildings, target of the study, three criteria were defined: buildings built before 1990, with 2 to 6 floors and with renovation needs in the exterior envelope.

VIP A B C. Vacuum Insulation Panels Applied in Building Constructions

Energy Technology Data Exchange (ETDEWEB)

Tenpierik, M.J.

2010-02-01

Due to sustainability and due to international treaties, it is desired and required to reduce greenhouse gas emissions drastically. One contributor to these emissions is the burning of fossil fuels for generating power and electricity to be used in and for buildings. Buildings and building-related processes are responsible for about 40% of the primary energy consumption in the European Union. More than half of this energy is applied for heating systems in dwellings and commercial buildings. The European Union therefore has laid down new energy performance requirements for buildings in the European Directive on the Energy Performance of Buildings. Moreover, a reduction of energy losses of buildings during their occupational phase is important for facilitating the implementation of sustainable energy sources in the built environment. Increasing the insulation value of the envelope of buildings may contribute to this reduction of primary energy use. Two strategies can be followed. The first strategy is to increase the thickness of the thermal insulation layer. Until recently, this strategy has primarily been adopted. If, however, German or Swiss Passivhaus standard is applied, the thickness of this insulation layer would increase to beyond 30 cm, resulting in very thick building enclosures. The second, more innovative, strategy for reducing energy losses through the building skin would be the application of more effective thermal insulators. One such more effective thermal insulator is a vacuum insulation panel, abbreviated as VIP. A VIP consists of an open-celled core material which is evacuated and then tightly sealed into a barrier envelope to maintain this vacuum. The vacuum inside the pores of the core material reduces the thermal conductivity of the product significantly, as a result of which the thickness of the insulation layer can be reduced to obtain a certain performance. This reduction of thickness is among the most promising features for large

The epigenetics of nuclear envelope organization and disease

International Nuclear Information System (INIS)

Schirmer, Eric C.

2008-01-01

Mammalian chromosomes and some specific genes have non-random positions within the nucleus that are tissue-specific and heritable. Work in many organisms has shown that genes at the nuclear periphery tend to be inactive and altering their partitioning to the interior results in their activation. Proteins of the nuclear envelope can recruit chromatin with specific epigenetic marks and can also recruit silencing factors that add new epigenetic modifications to chromatin sequestered at the periphery. Together these findings indicate that the nuclear envelope is a significant epigenetic regulator. The importance of this function is emphasized by observations of aberrant distribution of peripheral heterochromatin in several human diseases linked to mutations in NE proteins. These debilitating inherited diseases range from muscular dystrophies to the premature aging progeroid syndromes and the heterochromatin changes are just one early clue for understanding the molecular details of how they work. The architecture of the nuclear envelope provides a unique environment for epigenetic regulation and as such a great deal of research will be required before we can ascertain the full range of its contributions to epigenetics

Operating envelope to minimize probability of fractures in Zircaloy-2 pressure tubes

International Nuclear Information System (INIS)

Azer, N.; Wong, H.

1994-01-01

The failure mode of primary concern with Candu pressure tubes is fast fracture of a through-wall axial crack, resulting from delayed hydride crack growth. The application of operating envelopes is demonstrated to minimize the probability of fracture in Zircaloy-2 pressure tubes based on Zr-2.5%Nb pressure tube experience. The technical basis for the development of the operating envelopes is also summarized. The operating envelope represents an area on the pressure versus temperature diagram within which the reactor may be operated without undue concern for pressure tube fracture. The envelopes presented address both normal operating conditions and the condition where a pressure tube leak has been detected. The examples in this paper are prepared to illustrate the methodology, and are not intended to be directly applicable to the operation of any specific reactor. The application of operating envelopes to minimized the probability of fracture in 80 mm diameter Zircaloy-2 pressure tubes has been discussed. Both normal operating and leaking pressure tube conditions have been considered. 3 refs., 4 figs

Nature of 'unseen' galactic envelopes

International Nuclear Information System (INIS)

McCrea, W.H.

1983-01-01

In this paper, it is suggested that unseen matter in a galactic envelope or in a group of galaxies may consist of substellar bodies originating as the first permanent 'stars' in the formation of a very massive galaxy according to a model for galaxy-formation on the basis of simple big-bang cosmology. (Auth.)

Final deactivation report on the Radioisotope Production Lab-E, Building 3032, at Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1997-09-01

The purpose of this report is to document the condition of Bldg. 3032, after completion of deactivation activities as outlined by the Department of Energy (DOE) Office of Nuclear Materials and Facility Stabilization Program (EM-60) guidance documentation. This report outlines the activities conducted to place the facility in a safe and environmentally sound condition for transfer to the DOE Office of Environmental Restoration Program (EM-40). This report provides a history and profile of Bldg. 3032 prior to commencing deactivation activities and a profile of the building after completion of deactivation activities. Turnover items, such as the Postdeactivation Surveillance ampersand Maintenance Plan, remaining hazardous materials, radiological controls, Safeguards and Security, quality assurance, facility operations, and supporting documentation provided in the EM-60 turnover package are discussed. Building 3032 will be used as the Health Physics Office for the Isotopes Facilities Deactivation Program area and will require access for these offices and to facilitate required surveillance and maintenance (S ampersand M) activities to maintain the building safety envelope. Bldg. 3032 was stabilized during deactivation so that when transferred to the EM-40 program, only a minimal S ampersand M effort would be required to maintain the building safety envelope. All materials have been removed from the building, and all utility systems, piping, and alarms have been deactivated except electricity and steam needed for the office areas

Safeguards Envelope Progress FY10

International Nuclear Information System (INIS)

Metcalf, Richard

2010-01-01

The Safeguards Envelope is a strategy to determine a set of specific operating parameters within which nuclear facilities may operate to maximize safeguards effectiveness without sacrificing safety or plant efficiency. This paper details the additions to the advanced operating techniques that will be applied to real plant process monitoring (PM) data from the Idaho Chemical Processing Plant (ICPP). Research this year focused on combining disparate pieces of data together to maximize operating time with minimal downtime due to safeguards. A Chi-Square and Croiser's cumulative sum were both included as part of the new analysis. Because of a major issue with the original data, the implementation of the two new tests did not add to the existing set of tests, though limited one-variable optimization made a small increase in detection probability. Additional analysis was performed to determine if prior analysis would have caused a major security or safety operating envelope issue. It was determined that a safety issue would have resulted from the prior research, but that the security may have been increased under certain conditions.

The dynamics of short envelope solitons in media with controlled dispersion

International Nuclear Information System (INIS)

Aseeva, N.V.; Gromov, E.M.; Tyutin, V.V.

2007-01-01

The dynamics of short envelope solitons in media with controlled dispersion is investigated in the framework of the third-order nonlinear Schroedinger equation. Evolution of the solitons amplitude is analyzed in the adiabatic approximation. The existence of short envelope solitons independent from linear dispersion inhomogeneity is shown

Calculation steps. Building integrated energy supply; Beregningsgang. Bygningsintegreret energiforsyning

Energy Technology Data Exchange (ETDEWEB)

Jensen, Rasmus L.; Noergaard, J.; Daniels, O.; Justesen, R.O.

2011-08-15

In the future, buildings will not only act as consumers of energy but as producers as well. For these ''prosumers'', energy production by use of solar panels, photovoltaics and heat pumps etc will be essential. The objective of this project was to find the most optimal combinations of building insulation and use of renewable energy sources in existing buildings in terms of economics and climate impacts. Five houses were analyzed based on different personal load, consumption profiles, solar orientation and proposed building envelope improvements and use of combinations of renewable energy systems. The analysis was conducted by making a large number of simulations. The present report describes the applied simulation models, and explains the results and computer codes. The parameter variations are described for each house as well as the common calculation steps for each house. The results are presented in case sheets, as performance graphs, and top-50 lists for the best cases regarding CO{sub 2} emission, energy consumption and economics. (ln)

Early Site Permit Demonstration Program: Plant parameters envelope report. Volume 1

Energy Technology Data Exchange (ETDEWEB)

1993-03-01

The Early Site Permit (ESP) Demonstration Program is the nuclear industry`s initiative for piloting the early resolution of siting-related issues before the detailed design proceedings of the combined operating license review. The ESP Demonstration Program consists of three phases. The plant parameters envelopes task is part of Phase 1, which addresses the generic review of applicable federal regulations and develops criteria for safety and environmental assessment of potential sites. The plant parameters envelopes identify parameters that characterize the interface between an ALWR design and a potential site, and quantify the interface through values selected from the Utility Requirements Documents, vendor design information, or engineering assessments. When augmented with site-specific information, the plant parameters envelopes provide sufficient information to allow ESPs to be granted based on individual ALWR design information or enveloping design information for the evolutionary, passive, or generic ALWR plants. This document is expected to become a living document when used by future applicants.

Translucent insulating building envelope

DEFF Research Database (Denmark)

Rahbek, Jens Eg

1997-01-01

A new type of translucent insulating material has been tested. This material is made of Celulose-Acetat and have a honey-comb structure. The material has a high solar transmittance and is highly insulating. The material is relatively cheap to produce. Danish Title: Translucent isolerende klimaskærm....

Spectral Envelope Transformation in Singing Voice for Advanced Pitch Shifting

Directory of Open Access Journals (Sweden)

José L. Santacruz

2016-11-01

Full Text Available The aim of the present work is to perform a step towards more natural pitch shifting techniques in singing voice for its application in music production and entertainment systems. In this paper, we present an advanced method to achieve natural modifications when applying a pitch shifting process to singing voice by modifying the spectral envelope of the audio excerpt. To this end, an all-pole model has been selected to model the spectral envelope, which is estimated using a constrained non-linear optimization. The analysis of the global variations of the spectral envelope was carried out by identifying changes of the parameters of the model along with the changes of the pitch. With the obtained spectral envelope transformation functions, we applied our pitch shifting scheme to some sustained vowels in order to compare results with the same transformation made by using the Flex Pitch plugin of Logic Pro X and pitch synchronous overlap and add technique (PSOLA. This comparison has been carried out by means of both an objective and a subjective evaluation. The latter was done with a survey open to volunteers on our website.

Energy management handbook for building operating engineers student workbook

Energy Technology Data Exchange (ETDEWEB)

1979-09-01

The handbook provides operating engineers with the basic information needed to implement specific energy conservation opportunities, and additional information is presented relative to the formulation and development of the energy management plan. Chapters are entitled: The Need for Energy Management (International Factors, The US Energy Situation, Energy and the Building Owner); The Fundamentals of Energy Consumption in Buildings (Energy Basics, Heat Basics, Heat Flow and the Building Envelope, Air and Comfort, Factors Affecting Energy Use In Buildings); Principles of Energy Conservation (Building Energy Consumption Characteristics); Planning the Energy Management Program (Obtaining Commitment and Support, Establishing the Energy Use Index, Organizing to Develop the Plan, Developing and Implementing the Plan); Conducting a Survey of Facilities and Operations (The Energy Audit, Preparation of Building and Systems Profile, Measurement and Instrumentation); Guidelines for Energy Conservation (Operator ECO's, Owner ECO'S); Developing the Draft Final Plan (Analyze Survey Findings, Putting the Plan on Paper, Review and Submit); Implementing the Program (Developing the Final Plan, Implementing the Plan, Monitoring and Updating the Program). A glossary is included and specific information on degree days and cooling hours for some selected cities and a computer energy study data for the New York Hilton are included in appendices. (MCW)

A low-energy building under arctic conditions – a case study

DEFF Research Database (Denmark)

Norling, Casper Roland; Rode, Carsten; Svendsen, Svend

2006-01-01

Greenland is a relatively small community with limited natural resources, which results in the necessity to import all supplies, including a big share of the energy. Because of this, it is important to decrease the energy consumption. This can be done by developing new construction technology wit...... in the new Greenlandic building regulations....... with larger focus on energy efficiency. Therefore a low-energy house, located in Sisimiut, has been constructed. The low-energy house will be a forerunner for the development of new building element designs and technologies in Greenland. In the forthcoming years, the house will also be a base for scientific...... projects which will evaluate the design of the low-energy house including an assessment of the effect of the highly insulated building envelope, advanced windows and a ventilation system with heat recovery, all of which cuts the energy consumption of the building to half of what will be the requirement...

Norwegian building's energy policy: multiple and inconsistent; Norsk byggenergipolitikk: mangfoldig og inkonsistent

Energy Technology Data Exchange (ETDEWEB)

Boasson, Elin Lerum

2009-09-15

Historically, Norwegian building-construction policies have been part of the state's welfare policy. After 2000, a new conceptualisation of buildings emerged in Europe. Buildings were now regarded as a part of the energy system. The term 'energy performance of buildings' covers both the thermal quality of the building envelope and on-site energy production. In 2002 the EU developed an Energy Performance of Buildings Directive, while EU state aid regulations constrained national support schemes directed at fostering buildings with high energy performance. The building construction industry is a loosely coupled industry, and by year 2000 building construction was rather de-politicized. Although governmental regulations tend to be developed by governmental organisations and research communities in collaboration, political executives have, from time to time after year 2000, engaged directly in the development policy regarding energy performance of buildings. This report explores: 1) Why have Norwegian governments, in the period between 2000 and 2008, developed four strains of policies directed toward promoting buildings with high energy performance? 2) How did the European environment, the building construction sector (industry and governmental regulators) and the Norwegian governmental hierarchical steering intervene and shape the outcomes? (Author)

Minergie-P - Illustrated guide to a sustainable building standard; Minergie-P. Illustrierte Anleitung fuer einen zukunktsfaehigen Baustandard

Energy Technology Data Exchange (ETDEWEB)

Ragonesi, M. [Ragonesi Strobel und Partner, Luzern (Switzerland); Menti, U.-P. [Zertifizierungsstelle Minergie-P, Hochschule Luzern, Technik und Architektur, Horw (Switzerland); Tschui, A. [W und P Engineering, Stansstad/Willisau (Switzerland); Zurfluh, B. [Ingenieurbuero Zurfluh Lottenbach HLK, Luzern (Switzerland)

2010-07-01

This comprehensive set of 123 slides presents an overview of the Swiss Minergie-P building standard with its prescriptions and requirements. The calculations required and building design are covered in detail, as is the certification of the buildings. Details on the requirements placed on the building envelope, its technical services and heat-protection in summer are presented and reviewed. It is stressed that simplicity and efficiency are important, as is efficient lighting and the use of energy-efficient office and household appliances. Various forms of heat supply including district heating, solar energy, heat pumps, natural gas and wood-pellets are reviewed as is heat-recovery and fan-assisted balanced ventilation. A large number of examples are presented and discussed.

Smart Building: Decision Making Architecture for Thermal Energy Management.

Science.gov (United States)

Uribe, Oscar Hernández; Martin, Juan Pablo San; Garcia-Alegre, María C; Santos, Matilde; Guinea, Domingo

2015-10-30

Smart applications of the Internet of Things are improving the performance of buildings, reducing energy demand. Local and smart networks, soft computing methodologies, machine intelligence algorithms and pervasive sensors are some of the basics of energy optimization strategies developed for the benefit of environmental sustainability and user comfort. This work presents a distributed sensor-processor-communication decision-making architecture to improve the acquisition, storage and transfer of thermal energy in buildings. The developed system is implemented in a near Zero-Energy Building (nZEB) prototype equipped with a built-in thermal solar collector, where optical properties are analysed; a low enthalpy geothermal accumulation system, segmented in different temperature zones; and an envelope that includes a dynamic thermal barrier. An intelligent control of this dynamic thermal barrier is applied to reduce the thermal energy demand (heating and cooling) caused by daily and seasonal weather variations. Simulations and experimental results are presented to highlight the nZEB thermal energy reduction.

Smart Building: Decision Making Architecture for Thermal Energy Management

Directory of Open Access Journals (Sweden)

Oscar Hernández Uribe

2015-10-01

Full Text Available Smart applications of the Internet of Things are improving the performance of buildings, reducing energy demand. Local and smart networks, soft computing methodologies, machine intelligence algorithms and pervasive sensors are some of the basics of energy optimization strategies developed for the benefit of environmental sustainability and user comfort. This work presents a distributed sensor-processor-communication decision-making architecture to improve the acquisition, storage and transfer of thermal energy in buildings. The developed system is implemented in a near Zero-Energy Building (nZEB prototype equipped with a built-in thermal solar collector, where optical properties are analysed; a low enthalpy geothermal accumulation system, segmented in different temperature zones; and an envelope that includes a dynamic thermal barrier. An intelligent control of this dynamic thermal barrier is applied to reduce the thermal energy demand (heating and cooling caused by daily and seasonal weather variations. Simulations and experimental results are presented to highlight the nZEB thermal energy reduction.

3D Modeling of Accretion Disks and Circumbinary Envelopes in Close Binaries

Science.gov (United States)

Bisikalo, D.

2010-12-01

A number of observations prove the complex flow structure in close binary stars. The gas dynamic structure of the flow is governed by the stream of matter from the inner Lagrange point, the accretion disk, the circum-disk halo, and the circumbinary envelope. Observations reflect the current state of a binary system and for their interpretation one should consider the gas dynamics of flow patterns. Three-dimensional numerical gasdynamical modeling is used to study the gaseous flow structure and dynamics in close binaries. It is shown that the periodic variations of the positions of the disk and the bow shock formed when the inner parts of the circumbinary envelope flow around the disk result in variations in both the rate of angular-momentum transfer to the disk and the flow structure near the Lagrange point L3. All these factors lead to periodic ejections of matter from the accretion disk and circum-disk halo into the outer layers of the circumbinary envelope. The results of simulations are used to estimate the physical parameters of the circumbinary envelope, including 3D matter distribution in it, and the matter-flow configuration and dynamics. The envelope becomes optically thick for systems with high mass-exchange rates, M⊙=10-8 Msun/year, and has a significant influence on the binary's observed features. The uneven phase distributions of the matter and density variations due to periodic injections of matter into the envelope are important for interpretations of observations of CBSs.

Economic assessment of electric energy storage for load shifting in positive energy building

DEFF Research Database (Denmark)

Dumont, Olivier; Do Carmo, Carolina Madeira Ramos; Georges, Emeline

2017-01-01

Net zero energy buildings and positive energy buildings are gaining more and more interest. This paper evaluates the impact of the integration of a battery in a positive energy building used to increase its self-consumption of electricity. Parametric studies are carried out by varying the buildin...... and a 3.7 kWh battery. Finally, simple correlations (based on the feed-in tariff, the annual electrical consumption and production) to predict the optimal size of battery and the lowest payback period are proposed.......Net zero energy buildings and positive energy buildings are gaining more and more interest. This paper evaluates the impact of the integration of a battery in a positive energy building used to increase its self-consumption of electricity. Parametric studies are carried out by varying the building...... envelope characteristics, the power supply system, the climate, the lighting and appliances profiles, the roof tilt angle, the battery size and the electricity tariffs, leading to 3200 cases. The analysis is performed on an annual basis in terms of self-consumption and self-production rate and payback...

Origin, differentiation and functional ultrastructure of egg envelopes in the cestode Echinococcus multilocularis Leuckart, 1863 (Cyclophyllidea: Taeniidae).

Science.gov (United States)

Świderski, Zdzisław; Miquel, Jordi; Azzouz-Maache, Samira; Pétavy, Anne-Françoise

2017-07-01

The origin, differentiation and functional ultrastructure of oncospheral or egg envelopes in Echinococcus multilocularis Leuckart, 1863 were studied by transmission electron microscopy (TEM) and cytochemistry. The purpose of our study is to describe the formation of the four primary embryonic envelopes, namely vitelline capsule, outer envelope, inner envelope and oncospheral membrane, and their transformation into the oncospheral or egg envelopes surrounding the mature hexacanth. This transformation takes place in the preoncospheral phase of embryonic development. The vitelline capsule and oncospheral membrane are thin membranes, while the outer and inner envelopes are thick cytoplasmic layers formed by two specific types of blastomeres: the outer envelope by cytoplasmic fusion of two macromeres and the inner envelope by cytoplasmic fusion of three mesomeres. Both outer and inner envelopes are therefore cellular in origin and syncytial in nature. During the advanced phase of embryonic development, the outer and inner envelopes undergo great modifications. The outer envelope remains as a metabolically active layer involved in the storage of glycogen and lipids for the final stages of egg development and survival. The inner envelope is the most important protective layer because of its thick layer of embryophoric blocks that assures oncospheral protection and survival. This embryophore is the principal layer of mature eggs, affording physical and physiological protection for the differentiated embryo or oncosphere, since the outer envelope is stripped from the egg before it is liberated. The embryophore is very thick and impermeable, consisting of polygonal blocks of an inert keratin-like protein held together by a cementing substance. The embryophore therefore assures extreme resistance of eggs, enabling them to withstand a wide range of environmental temperatures and physicochemical conditions.

A multi-resolution envelope-power based model for speech intelligibility

DEFF Research Database (Denmark)

Jørgensen, Søren; Ewert, Stephan D.; Dau, Torsten

2013-01-01

The speech-based envelope power spectrum model (sEPSM) presented by Jørgensen and Dau [(2011). J. Acoust. Soc. Am. 130, 1475-1487] estimates the envelope power signal-to-noise ratio (SNRenv) after modulation-frequency selective processing. Changes in this metric were shown to account well...... to conditions with stationary interferers, due to the long-term integration of the envelope power, and cannot account for increased intelligibility typically obtained with fluctuating maskers. Here, a multi-resolution version of the sEPSM is presented where the SNRenv is estimated in temporal segments...... with a modulation-filter dependent duration. The multi-resolution sEPSM is demonstrated to account for intelligibility obtained in conditions with stationary and fluctuating interferers, and noisy speech distorted by reverberation or spectral subtraction. The results support the hypothesis that the SNRenv...

Classification of buildings mold threat using electronic nose

Science.gov (United States)

Łagód, Grzegorz; Suchorab, Zbigniew; Guz, Łukasz; Sobczuk, Henryk

2017-07-01

Mold is considered to be one of the most important features of Sick Building Syndrome and is an important problem in current building industry. In many cases it is caused by the rising moisture of building envelopes surface and exaggerated humidity of indoor air. Concerning historical buildings it is mostly caused by outdated raising techniques among that is absence of horizontal isolation against moisture and hygroscopic materials applied for construction. Recent buildings also suffer problem of mold risk which is caused in many cases by hermetization leading to improper performance of gravitational ventilation systems that make suitable conditions for mold development. Basing on our research there is proposed a method of buildings mold threat classification using electronic nose, based on a gas sensors array which consists of MOS sensors (metal oxide semiconductor). Used device is frequently applied for air quality assessment in environmental engineering branches. Presented results show the interpretation of e-nose readouts of indoor air sampled in rooms threatened with mold development in comparison with clean reference rooms and synthetic air. Obtained multivariate data were processed, visualized and classified using a PCA (Principal Component Analysis) and ANN (Artificial Neural Network) methods. Described investigation confirmed that electronic nose - gas sensors array supported with data processing enables to classify air samples taken from different rooms affected with mold.

Estimating building energy consumption using extreme learning machine method

International Nuclear Information System (INIS)

Naji, Sareh; Keivani, Afram; Shamshirband, Shahaboddin; Alengaram, U. Johnson; Jumaat, Mohd Zamin; Mansor, Zulkefli; Lee, Malrey

2016-01-01

The current energy requirements of buildings comprise a large percentage of the total energy consumed around the world. The demand of energy, as well as the construction materials used in buildings, are becoming increasingly problematic for the earth's sustainable future, and thus have led to alarming concern. The energy efficiency of buildings can be improved, and in order to do so, their operational energy usage should be estimated early in the design phase, so that buildings are as sustainable as possible. An early energy estimate can greatly help architects and engineers create sustainable structures. This study proposes a novel method to estimate building energy consumption based on the ELM (Extreme Learning Machine) method. This method is applied to building material thicknesses and their thermal insulation capability (K-value). For this purpose up to 180 simulations are carried out for different material thicknesses and insulation properties, using the EnergyPlus software application. The estimation and prediction obtained by the ELM model are compared with GP (genetic programming) and ANNs (artificial neural network) models for accuracy. The simulation results indicate that an improvement in predictive accuracy is achievable with the ELM approach in comparison with GP and ANN. - Highlights: • Buildings consume huge amounts of energy for operation. • Envelope materials and insulation influence building energy consumption. • Extreme learning machine is used to estimate energy usage of a sample building. • The key effective factors in this study are insulation thickness and K-value.

Envelope detection using temporal magnetization dynamics of resonantly interacting spin-torque oscillator

Science.gov (United States)

Nakamura, Y.; Nishikawa, M.; Osawa, H.; Okamoto, Y.; Kanao, T.; Sato, R.

2018-05-01

In this article, we propose the detection method of the recorded data pattern by the envelope of the temporal magnetization dynamics of resonantly interacting spin-torque oscillator on the microwave assisted magnetic recording for three-dimensional magnetic recording. We simulate the envelope of the waveform from recorded dots with the staggered magnetization configuration, which are calculated by using a micromagnetic simulation. We study the data detection methods for the envelope and propose a soft-output Viterbi algorithm (SOVA) for partial response (PR) system as a signal processing system for three dimensional magnetic recording.

"Watts per person" paradigm to design net zero energy buildings: Examining technology interventions and integrating occupant feedback to reduce plug loads in a commercial building

Science.gov (United States)

Yagi Kim, Mika

As building envelopes have improved due to more restrictive energy codes, internal loads have increased largely due to the proliferation of computers, electronics, appliances, imaging and audio visual equipment that continues to grow in commercial buildings. As the dependency on the internet for information and data transfer increases, the electricity demand will pose a challenge to design and operate Net Zero Energy Buildings (NZEBs). Plug Loads (PLs) as a proportion of the building load has become the largest non-regulated building energy load and represents the third highest electricity end-use in California's commercial office buildings, accounting for 23% of the total building electricity consumption (Ecova 2011,2). In the Annual Energy Outlook 2008 (AEO2008), prepared by the Energy Information Administration (EIA) that presents long-term projections of energy supply and demand through 2030 states that office equipment and personal computers are the "fastest growing electrical end uses" in the commercial sector. This thesis entitled "Watts Per Person" Paradigm to Design Net Zero Energy Buildings, measures the implementation of advanced controls and behavioral interventions to study the reduction of PL energy use in the commercial sector. By integrating real world data extracted from an energy efficient commercial building of its energy use, the results produce a new methodology on estimating PL energy use by calculating based on "Watts Per Person" and analyzes computational simulation methods to design NZEBs.

Parametric study of the thermal performance of a typical administrative building in the six thermal zones according to the RTCM, using TRNSYS

Directory of Open Access Journals (Sweden)

Abdelghafour LAMRANI

2018-01-01

Full Text Available In this work, we present a parametric study of a new administrative building, located in El-Ksar El Kebir region (Morocco. In order to have a building that complies with the RTCM in a technically and economically sound manner, we have carried out a number of interventions to insulate the components of the building, namely external walls, exposed roofs and openings. In this perspective, we have modelled the building envelope as a multi-zone building in TRNSYS and we have adopted an occupation scenario for this type of building. After determining the optimal insulation solutions, we simulated the administrative building in the five other thermal zones, to determine its feasibility in the latter.

Calculation of CWKB envelope in boson and fermion productions

International Nuclear Information System (INIS)

Biswas, S.; Chowdhury, I.

2007-01-01

We present the calculation of envelope of boson and of both low-and high-mass fermion production at the end of inflation when the coherently oscillating inflations decay into bosons and fermions. We consider three different models of inflation and use CWKB technique to calculate the envelope to understand the structure of resonance band formation. We observe that though low-mass fermion production is not effective in preheating because of Pauli blocking, it is quite probable for high-mass fermion to take part in pre heating. (author)

Progress in the integration of the ITER plant systems in auxiliary buildings

International Nuclear Information System (INIS)

Kotamäki, M.; Cordier, J.-J.; Kuehn, I.; Perrin, J.-L.; Sweeney, S.; Villedary, B.

2016-01-01

Highlights: • Usage of 3D CAD model in ITER configuration management presented. • 3D CAD models efficient in configuration and interface management. • Costly and schedule delaying changes avoided with proper interface management. • ITER buildings construction progressing. - Abstract: The ITER Tokamak machine is located in the center of Tokamak complex buildings consisting of Tokamak, Diagnostic, and Tritium buildings. Around the Tokamak complex there are over 30 auxiliary buildings housing various plant systems serving the Tokamak machine either directly or indirectly. The layout and space allocation of each auxiliary building and plant systems housed by the building are represented in the so-called Configuration Management Models (CMM). These are light 3D CAD models that define the required space envelope and the physical interfaces between the systems and the buildings and in-between the systems. The paper describes the CMM and interface management processes of the ITER auxiliary buildings and plant systems, and discusses the preparations for the plant installation phase. In addition, the current baseline configuration of the ITER plant systems in auxiliary buildings is described together with the recent developments in the configuration of different systems, as well as the current status of the construction of the buildings.

Progress in the integration of the ITER plant systems in auxiliary buildings

Energy Technology Data Exchange (ETDEWEB)

Kotamäki, M., E-mail: miikka.kotamaki@iter.org; Cordier, J.-J.; Kuehn, I.; Perrin, J.-L.; Sweeney, S.; Villedary, B.

2016-11-01

Highlights: • Usage of 3D CAD model in ITER configuration management presented. • 3D CAD models efficient in configuration and interface management. • Costly and schedule delaying changes avoided with proper interface management. • ITER buildings construction progressing. - Abstract: The ITER Tokamak machine is located in the center of Tokamak complex buildings consisting of Tokamak, Diagnostic, and Tritium buildings. Around the Tokamak complex there are over 30 auxiliary buildings housing various plant systems serving the Tokamak machine either directly or indirectly. The layout and space allocation of each auxiliary building and plant systems housed by the building are represented in the so-called Configuration Management Models (CMM). These are light 3D CAD models that define the required space envelope and the physical interfaces between the systems and the buildings and in-between the systems. The paper describes the CMM and interface management processes of the ITER auxiliary buildings and plant systems, and discusses the preparations for the plant installation phase. In addition, the current baseline configuration of the ITER plant systems in auxiliary buildings is described together with the recent developments in the configuration of different systems, as well as the current status of the construction of the buildings.

Failure envelope approach for consolidated undrained capacity of shallow foundations

OpenAIRE

Vulpe, Cristina; Gourvenec, Susan; Leman, Billy; Fung, Kah Ngii

2016-01-01

A generalized framework is applied to predict consolidated undrained VHM failure envelopes for surface circular and strip foundations. The failure envelopes for consolidated undrained conditions are shown to be scaled from those for unconsolidated undrained conditions by the uniaxial consolidated undrained capacities, which are predicted through a theoretical framework based on fundamental critical state soil mechanics. The framework is applied to results from small-strain finite-element anal...

Evaluation of fault-normal/fault-parallel directions rotated ground motions for response history analysis of an instrumented six-story building

Science.gov (United States)

Kalkan, Erol; Kwong, Neal S.

2012-01-01

According to regulatory building codes in United States (for example, 2010 California Building Code), at least two horizontal ground-motion components are required for three-dimensional (3D) response history analysis (RHA) of buildings. For sites within 5 km of an active fault, these records should be rotated to fault-normal/fault-parallel (FN/FP) directions, and two RHA analyses should be performed separately (when FN and then FP are aligned with the transverse direction of the structural axes). It is assumed that this approach will lead to two sets of responses that envelope the range of possible responses over all nonredundant rotation angles. This assumption is examined here using a 3D computer model of a six-story reinforced-concrete instrumented building subjected to an ensemble of bidirectional near-fault ground motions. Peak responses of engineering demand parameters (EDPs) were obtained for rotation angles ranging from 0° through 180° for evaluating the FN/FP directions. It is demonstrated that rotating ground motions to FN/FP directions (1) does not always lead to the maximum responses over all angles, (2) does not always envelope the range of possible responses, and (3) does not provide maximum responses for all EDPs simultaneously even if it provides a maximum response for a specific EDP.

Luminescent solar concentrators for building-integrated photovoltaics

Science.gov (United States)

Meinardi, Francesco; Bruni, Francesco; Brovelli, Sergio

2017-12-01

The transition to fully energetically sustainable architecture through the realization of so-called net zero-energy buildings is currently in progress in areas with low population density. However, this is not yet true in cities, where the cost of land for the installation of ground photovoltaic (PV) is prohibitively high and the rooftop space is too scarce to accommodate the PV modules necessary for sustaining the electrical requirements of tall buildings. Thus, new technologies are being investigated to integrate solar-harvesting devices into building façades in the form of PV windows or envelope elements. Luminescent solar concentrators (LSCs) are the most promising technology for semi-transparent, electrodeless PV glazing systems that can be integrated 'invisibly' into the built environment without detrimental effects to the aesthetics of the building or the quality of life of the inhabitants. After 40 years of research, recent breakthroughs in the realization of reabsorption-free emitters with broadband absorption have boosted the performance of LSCs to such a degree that they might be commercialized in the near future. In this Perspective, we explore the successful strategies that have allowed this change of pace, examining and comparing the different types of chromophores and waveguide materials, and discuss the issues that remain to be investigated for further progress.

Data Envelopment Analysis (DEA) Model in Operation Management

Science.gov (United States)

Malik, Meilisa; Efendi, Syahril; Zarlis, Muhammad

2018-01-01

Quality management is an effective system in operation management to develops, maintains, and improves quality from groups of companies that allow marketing, production, and service at the most economycal level as well as ensuring customer satisfication. Many companies are practicing quality management to improve their bussiness performance. One of performance measurement is through measurement of efficiency. One of the tools can be used to assess efficiency of companies performance is Data Envelopment Analysis (DEA). The aim of this paper is using Data Envelopment Analysis (DEA) model to assess efficiency of quality management. In this paper will be explained CCR, BCC, and SBM models to assess efficiency of quality management.

Asymmetry of the envelope of supernova 1987A

Energy Technology Data Exchange (ETDEWEB)

Papaliolios, C.; Karovska, M.; Koechlin, L.; Nisenson, P.; Standley, C.; Heathcote, S.

1989-04-13

The supernova SN1987A in the Large Magellanic Cloud has been observed by high-angular-resolution speckle interferometry since 25 March (30 days after the explosion) with the 4-m telescope at the Cerro Tololo Interamerican Observatory. Data obtained on 25 March and 2 April 1987 revealed a second bright 'companion' source separated from the supernova by 60 milliarcseconds and less than three magnitudes fainter than the supernova. Measurements of the average diameter of the supernova envelope have been made from data recorded from March 1987 to April 1988. Here we present a more detailed analysis of these data, which shows that the expanding envelope is asymmetric. (author).

Asymmetry of the envelope of supernova 1987A

International Nuclear Information System (INIS)

Papaliolios, C.; Karovska, M.; Koechlin, L.; Nisenson, P.; Standley, C.; Heathcote, S.

1989-01-01

The supernova SN1987A in the Large Magellanic Cloud has been observed by high-angular-resolution speckle interferometry since 25 March (30 days after the explosion) with the 4-m telescope at the Cerro Tololo Interamerican Observatory. Data obtained on 25 March and 2 April 1987 revealed a second bright 'companion' source separated from the supernova by 60 milliarcseconds and less than three magnitudes fainter than the supernova. Measurements of the average diameter of the supernova envelope have been made from data recorded from March 1987 to April 1988. Here we present a more detailed analysis of these data, which shows that the expanding envelope is asymmetric. (author)

Refractive index dispersion measurement using carrier-envelope phasemeters

International Nuclear Information System (INIS)

Hansinger, Peter; Töpfer, Philipp; Adolph, Daniel; Hoff, Dominik; Rathje, Tim; Sayler, A Max; Paulus, Gerhard G; Dimitrov, Nikolay; Dreischuh, Alexander

2017-01-01

We introduce a novel method for direct and accurate measurement of refractive index dispersion based on carrier-envelope phase detection of few-cycle laser pulses, exploiting the difference between phase and group velocity in a dispersive medium. In a layout similar to an interferometer, two carrier-envelope phasemeters are capable of measuring the dispersion of a transparent or reflective sample, where one phasemeter serves as the reference and the other records the influence of the sample. Here we report on proof-of-principle measurements that already reach relative uncertainties of a few 10 −4 . Further development is expected to allow for unprecedented precision. (paper)

Deep Energy Retrofit Guidance for the Building America Solutions Center

Energy Technology Data Exchange (ETDEWEB)

Less, Brennan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Walker, Iain [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2015-01-01

The U.S. DOE Building America program has established a research agenda targeting market-relevant strategies to achieve 40% reductions in existing home energy use by 2030. Deep Energy Retrofits (DERs) are part of the strategy to meet and exceed this goal. DERs are projects that create new, valuable assets from existing residences, by bringing homes into alignment with the expectations of the 21st century. Ideally, high energy using, dated homes that are failing to provide adequate modern services to their owners and occupants (e.g., comfortable temperatures, acceptable humidity, clean, healthy), are transformed through comprehensive upgrades to the building envelope, services and miscellaneous loads into next generation high performance homes. These guidance documents provide information to aid in the broader market adoption of DERs.

Building Envelope Thermal Performance Assessment Using Visual Programming and BIM, based on ETTV requirement of Green Mark and GreenRE

OpenAIRE

Taki Eddine Seghier; Lim Yaik Wah; Mohd Hamdan Ahmad; Williams Opeyemi Samuel

2017-01-01

Accomplishment of green building design requirements and the achievement of the targeted credit points under a specific green rating system are known to be a task that is very challenging. Building Information Modeling (BIM) design process and tools have already made considerable advancements in green building design and performance analysis. However, Green building design process is still lack of tools and workflows that can provide real-time feedback of building sustainability and rating du...

On the relationship between multi-channel envelope and temporal fine structure

DEFF Research Database (Denmark)

Søndergaard, Peter Lempel; Decorsiere, Remi Julien Blaise; Dau, Torsten

2011-01-01

The envelope of a signal is broadly defined as the slow changes in time of the signal, where as the temporal fine structure (TFS) are the fast changes in time, i.e. the carrier wave(s) of the signal. The focus of this paper is on envelope and TFS in multi-channel systems. We discuss the differenc...

Symmetries and invariants of the oscillator and envelope equations with time-dependent frequency

Directory of Open Access Journals (Sweden)

Hong Qin

2006-05-01

Full Text Available The single-particle dynamics in a time-dependent focusing field is examined. The existence of the Courant-Snyder invariant, a fundamental concept in accelerator physics, is fundamentally a result of the corresponding symmetry admitted by the harmonic oscillator equation with linear time-dependent frequency. It is demonstrated that the Lie algebra of the symmetry group for the oscillator equation with time-dependent frequency is eight dimensional, and is composed of four independent subalgebras. A detailed analysis of the admitted symmetries reveals a deeper connection between the nonlinear envelope equation and the oscillator equation. A general theorem regarding the symmetries and invariants of the envelope equation, which includes the existence of the Courant-Snyder invariant as a special case, is demonstrated. As an application to accelerator physics, the symmetries of the envelope equation enable a fast numerical algorithm for finding matched solutions without using the conventional iterative Newton’s method, where the envelope equation needs to be numerically integrated once for every iteration, and the Jacobi matrix needs to be calculated for the envelope perturbation.

Greening Existing Buildings in Contemporary Iraqi Urban Reality/ Virtual Model

Directory of Open Access Journals (Sweden)

Saba Jabar Neama Al-Khafaji

2015-11-01

Full Text Available The approach of greening existing buildings, is an urgent necessity, because the greening operation provides the speed and optimal efficiency in the environmental performance, as well as keeping up with the global green architecture revolution. Therefore, greening existing buildings in Iraq is important for trends towards renewable energies, because of what the country went through economic conditions and crises and wars which kept the country away from what took place globally in this issue. The research problem is: insufficient knowledge about the importance and the mechanism of the greening of existing buildings, including its environmental and economic dimensions, by rationalization of energy consumption and preserving the environment. The research objective is: clarifying the importance of greening existing buildings environmentally and economically, providing a virtual experience for greening the presidency building of Baghdad University, through advanced computer program. The main conclusions is: there is difference representing by reducing the disbursed thermal loads amount for cooling in summer and heating in winter through the use of computerized program (DesignBuilder and that after the implementation of greening operations on the building envelope, which confirms its effectiveness in raising the energy performance efficiency inside the building. Hence, the importance of the application of greening existing buildings approach in Iraq, to bring back Iraqi architecture to environmental and local track proper.

A Retrofit Tool for Improving Energy Efficiency of Commercial Buildings

Energy Technology Data Exchange (ETDEWEB)

Levine, Mark; Feng, Wei; Ke, Jing; Hong, Tianzhen; Zhou, Nan

2013-06-06

Existing buildings will dominate energy use in commercial buildings in the United States for three decades or longer and even in China for the about two decades. Retrofitting these buildings to improve energy efficiency and reduce energy use is thus critical to achieving the target of reducing energy use in the buildings sector. However there are few evaluation tools that can quickly identify and evaluate energy savings and cost effectiveness of energy conservation measures (ECMs) for retrofits, especially for buildings in China. This paper discusses methods used to develop such a tool and demonstrates an application of the tool for a retrofit analysis. The tool builds on a building performance database with pre-calculated energy consumption of ECMs for selected commercial prototype buildings using the EnergyPlus program. The tool allows users to evaluate individual ECMs or a package of ECMs. It covers building envelope, lighting and daylighting, HVAC, plug loads, service hot water, and renewable energy. The prototype building can be customized to represent an actual building with some limitations. Energy consumption from utility bills can be entered into the tool to compare and calibrate the energy use of the prototype building. The tool currently can evaluate energy savings and payback of ECMs for shopping malls in China. We have used the tool to assess energy and cost savings for retrofit of the prototype shopping mall in Shanghai. Future work on the tool will simplify its use and expand it to cover other commercial building types and other countries.

Bursting the Bubble - Nuclear Envelope Rupture as a Path to Genomic Instability?

NARCIS (Netherlands)

Shah, P.; Wolf, K.A.; Lammerding, J.

2017-01-01

The nuclear envelope safeguards the genetic material inside the nucleus by separating it from the cytoplasm. Until recently, it was assumed that nuclear envelope (NE) breakdown occurs only in a highly controlled fashion during mitosis when the chromatin is condensed and divided between the daughter

Change rules of a stratospheric airship’s envelope shape during ascent process

Directory of Open Access Journals (Sweden)

Shuai Zhao

2017-04-01

Full Text Available Stratospheric airship is a special near-space air vehicle, and has more advantages than other air vehicles, such as long endurance, strong survival ability, excellent resolution, low cost, and so on, which make it an ideal stratospheric platform. It is of great significance to choose a reasonable and effective way to launch a stratospheric airship to the space for both academic research and engineering applications. In this paper, the non-forming launch way is studied and the method of differential pressure gradient is used to study the change rules of the airship’s envelope shape during the ascent process. Numerical simulation results show that the head of the envelope will maintain the inflatable shape and the envelope under the zero-pressure level will be compressed into a wide range of wrinkles during the ascent process. The airship’s envelope will expand with the ascent of the airship and the position of the zero-pressure level will move downward constantly. At the same time, the envelope will gradually form a certain degree of stiffness under the action of the inner and external differential pressure. The experimental results agree well with the analytical results, which shows that the non-forming launch way is effective and reliable, and the analytical method has exactness and feasibility.

Residential Solar-Based Seasonal Thermal Storage Systems in Cold Climates: Building Envelope and Thermal Storage

Directory of Open Access Journals (Sweden)

Alexandre Hugo

2012-10-01

Full Text Available The reduction of electricity use for heating and domestic hot water in cold climates can be achieved by: (1 reducing the heating loads through the improvement of the thermal performance of house envelopes, and (2 using solar energy through a residential solar-based thermal storage system. First, this paper presents the life cycle energy and cost analysis of a typical one-storey detached house, located in Montreal, Canada. Simulation of annual energy use is performed using the TRNSYS software. Second, several design alternatives with improved thermal resistance for walls, ceiling and windows, increased overall air tightness, and increased window-to-wall ratio of South facing windows are evaluated with respect to the life cycle energy use, life cycle emissions and life cycle cost. The solution that minimizes the energy demand is chosen as a reference house for the study of long-term thermal storage. Third, the computer simulation of a solar heating system with solar thermal collectors and long-term thermal storage capacity is presented. Finally, the life cycle cost and life cycle energy use of the solar combisystem are estimated for flat-plate solar collectors and evacuated tube solar collectors, respectively, for the economic and climatic conditions of this study.

Evolution of a blue supergiant with a neutron star companion immersed in its envelope

International Nuclear Information System (INIS)

Delgado, A.J.

1980-01-01

The evolution of a binary system consisting of 1 Msub(sun) neutron star and a 25 Msub(sun) blue supergiant through a phase of common envelope is investigated. We include the effects of an additional energy source on the supergiant's envelope, due to the presence of the neutron star, and variable mass loss from the system, taken as proportional to the total luminosity. The results indicate that, independently of the initial period, the system loses its whole envelope as a consequence of the common envelope phase, the final product of this being a detached system, consisting of a neutron star and a helium star. (orig.)

The Experimental Research on Seismic Capacity of the Envelope Systems with Steel Frame

Science.gov (United States)