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The paper describes the principles of ventilation of underground structures, tunnels and corridors. It also presents a theoretical method of assessment of corridor structures where primary monitored values are velocity of spreading, temperature and depth of forehead of smoke wave in dependance on time and distance from the centre of fire. Results predicated by a theoretical method are compared to the values measured in a real large-scale experiment conducted in the tunnel Valík on the D5 motorway in the Czech Republic. This paper evaluates a possible use of theoretical calculation for constructions of tunnels. The presented method is based on a buoyancy of flue gases. At common constructions is the buoyancy effect one of the most significant phenomena, which affects the smoke movement. The specific type of tunnel constructions is the cause of phenomena that fundamentally affect the smoke flow. The importance of a buoyancy effect decreases significantly while the openness for tunnel constructions and the effect of fire ventilation becomes the major influences. These described effects are the cause of significant variances in realized experiments and applied theoretical method. Based on mentioned important discrepancies it is impossible to recommend this presented calculation method for using of tunnel constructions. The method would require an important modification so that would take into account the specifics of tunnel constructions. [ABSTRACT FROM AUTHOR]

Indoor carbon dioxide ( CO2) concentrations have been used for decades to characterize building ventilation and indoor air quality. Many of these applications require rates of CO2 generation from the building occupants, which are currently based on approaches and data that are several decades old. However, CO2 generation rates can be derived from well-established concepts within the fields of human metabolism and exercise physiology, which relate these rates to body size and composition, diet, and level of physical activity. This paper reviews how CO2 generation rates have been estimated in the past and discusses how they can be characterized more accurately. Based on this information, a new approach to estimating CO2 generation rates is presented, which is based on the described concepts from the fields of human metabolism and exercise physiology. Using this approach and more recent data on body mass and physical activity, values of CO2 generation rates from building occupants are presented along with the variability that may occur based on body mass and activity data. [ABSTRACT FROM AUTHOR]

This paper describes the development of reliability-targeted ground snow load maps for use in building (roof) design. The proposed procedures aim to ensure that structures designed achieve a target safety index, taken to be 3.0 as defined in ASCE 7 (ASCE 2010). When applied to the U.S. state of Colorado, the reliability-targeted mapping procedure shows that to achieve this target reliability index, design ground snow loads may need to be larger or smaller than the 50-year return period load that ASCE 7 currently stipulates for design, depending on the site and winter climate conditions at that site. Sites with larger coefficients of variation in the annual maximum snow load (in Colorado, lower-altitude sites) generally need design loads larger than the 50-year values. The paper also advances snow reliability assessment procedures through the proposal of a new model for the ground-to-roof conversion factor needed for quantifying roof snow loads as a function of ground snow loads. Spatial smoothing and altitude-dependent mapping procedures are described. [ABSTRACT FROM AUTHOR]

Using synthetic aperture radar (SAR) interferometry to monitor long-term millimeter-level deformation of urban infrastructures, such as individual buildings and bridges, is an emerging and important field in remote sensing. In the state-of-the-art methods, deformation parameters are retrieved and monitored on a pixel basis solely in the SAR image domain. However, the inevitable side-looking imaging geometry of SAR results in undesired occlusion and layover in urban area, rendering the current method less competent for a semantic-level monitoring of different urban infrastructures. This paper presents a framework of a semantic-level deformation monitoring by linking the precise deformation estimates of SAR interferometry and the semantic classification labels of optical images via a 3-D geometric fusion and semantic texturing. The proposed approach provides the first “SARptical” point cloud of an urban area, which is the SAR tomography point cloud textured with attributes from optical images. This opens a new perspective of InSAR deformation monitoring. Interesting examples on bridge and railway monitoring are demonstrated. [ABSTRACT FROM PUBLISHER]

Purpose The purpose of the paper is to analyze the relationship between maintenance of existent and investment in new infrastructure in Norwegian local governments.Design/methodology/approach A reduced form vector autoregressive system is estimated using a 29-year-long panel data set for the Norwegian local governments.Findings The data reveal that increased investment in new infrastructure sparks little, if any, increase in maintenance. The results also indicate that increased maintenance expenditures spark new investments. Because more investments mean more infrastructure and adequate maintenance should give that investments are not caused by maintenance, the results suggest that the local governments have not optimized their maintenance scheduling in this period.Originality/value Even though maintenance and investment are large expenditures that both serve as inputs to the stock of infrastructure, little is known about the relationship between the two. The findings in this paper suggests that Norwegian local governments have not planned their maintenance and investments well in the past, and this can be part of the explanation as to why local public infrastructure in Norway is presently in poor condition. [ABSTRACT FROM AUTHOR]

Doors and windows are an important part of the building envelope, the weatherability of doors and windows can directly affect the performance of external windows, thus affecting the overall energy-saving performance of the building. Based on the weatherability evaluation method and equipment of the subject, this paper studies the weatherability test scheme, conducts the weatherability test on the high-performance plastic energy-saving window developed by the subject,analyzes the performance of the energy-saving window before and after the weatherability test, analyzes the reasons that affect the weatherability of the window, and proposes improvement methods. [ABSTRACT FROM AUTHOR]

Digitization of buildings requires the systematic handling of a variety and volumes of data. It is a common vision to aim for coordinated homogenization of data structures, enabled by the classification of information. This paper studies the role of building information standards for classification in digitization of the building life cycle. It draws on science and technology studies of information technology standards, big data and building information modelling (BIM) in building research. The approach is based on performativity of standards for information systems, viewing performativity as potentially non-linear and multiple. The five-year design process of a large hospital in Denmark is examined as episodes of performance of the building information standard, particularly one recent standard, the Cuneco Classification System (CCS). The study shows that despite client demands, several building information standards are active over time: an ‘expansive’ design brief process adds user demands and uses room classification. Another process diminishes the design brief more than 50%, with several standards in use. The client’s facilities management system, which performs the structuring of data ‘backwards’ into the design process, makes architects and engineers (but not contractors) use CCS. This fragmentation of performing standards is denoted ‘multiple performativities’ and includes temporal and compartmental performativity. [ABSTRACT FROM PUBLISHER]

The digital integration of built-environment practices aims to bridge a large variety of organizations to improve building delivery and operation. However, recent research on building information modelling (BIM) reported organizational challenges arising from digital integration. This suggests a need to develop a critical perspective on digital-integration-driven organizational change. Adopting a practice-based approach, this paper exposes the practice-level phenomenon responsible for the ongoing change to develop a critical understanding and enable better interventions. The concepts of ‘simplification’ and ‘systematization’ of digital integration are developed from previous literature and then used to explore and interrelate the practice-level experiences of digital integration (i.e.the experience of the change fromwithin) and the emerging patterns of interactions (i.e.the picture of the change fromoutside) in a BIM-enabled design project. The concept of ‘ordering in disguise’ is proposed to capture this phenomenon. It shows that practitioners experience digital integration as various task-specific instances of unresponsive technology. However, they are unaware that their ongoing efforts to accommodate it actually further reinforce digital integration’s simplification and systematization. This makes the unresponsiveness of technology harder to challenge, and ultimately forces the organization to change and adapt to it. Implications for management of practice are outlined. [ABSTRACT FROM PUBLISHER]

The goal of maintaining users' thermal comfort conditions in indoor environments may require complex regulation procedures and a proper energy management. This problem is being widely analyzed, since it has a direct effect on users' productivity. This paper presents an economic model-based predictive control (MPC) whose main strength is the use of the day-ahead price (DAP) in order to predict the energy consumption associated with the heating, ventilation and air conditioning (HVAC). In this way, the control system is able to maintain a high thermal comfort level by optimizing the use of the HVAC system and to reduce, at the same time, the energy consumption associated with it, as much as possible. Later, the performance of the proposed control system is tested through simulations with a non-linear model of a bioclimatic building room. Several simulation scenarios are considered as a test-bed. From the obtained results, it is possible to conclude that the control system has a good behavior in several situations, i.e., it can reach the users' thermal comfort for the analyzed situations, whereas the HVAC use is adjusted through the DAP; therefore, the energy savings associated with the HVAC is increased. [ABSTRACT FROM AUTHOR]

This paper presents a statistical approach for uncertainty and sensitivity analyses applied to 14 inputs whose 10 properties associated with brick material, using the four different EnergyPlus wall models. The variability of inputs has been extracted from several characterization works presented in IEA Annexes 14, 24 and 55, being coherent to the lack of knowledge in the early design stage. Besides the methodology, this paper presents the moisture effects on cooling energy demand and indoor air conditions, using a simple building geometry and the humid climate of Singapore. Results are presented in terms of uncertainty quantification, most uncertain parameters and sensitivity indices for all models, illustrating the impact of moisture and the importance of the need to well define moisture-dependent functions. The methodology is well adapted for use in complex interactive models with a low-cost simulation and can be used to reduce uncertainties in the design stage and promote reliability of retrofitting assessment. [ABSTRACT FROM PUBLISHER]

Environment model is an important component of an artificial society. To level up the resolution of residence-building environment models in artificial Beijing, we divide residential buildings in Beijing into two categories, which are noncommunity residential buildings and community residential buildings, and statistically analyze the numbers of floors and areas of the real residential buildings. In this paper, we have exhibited the distribution of numbers of floors in noncommunity residential buildings and community residential buildings. Furthermore, we analyze the distribution of areas of noncommunity residential buildings and residence-use proportions of community zones by Nonlinear Regression. Results indicate that areas of noncommunity residential buildings in Beijing obey the log-normal distribution and residence-use proportions of community zones obey normal distribution. According to the statistical models, the virtual residential buildings in artificial Beijing can be endowed with rational attribute values. [ABSTRACT FROM AUTHOR]

The physical adaptability of buildings is very important in today's fast-changing business environment. The actors who invest in long-term adaptability are positioned better to the changes during the life cycle of a building. This conceptual paper argues that the current dominating real estate (property) investment analysis theories do not accommodate enough building design-related information (i.e.physical asset characteristics), which results in long-term loss of competitiveness and unsustainable use of built environment resources. It is demonstrated that physical asset characteristics can create valuable real options that should be acknowledged in real estate investment analysis and management. The real estate investment literature has not so far been able to produce a widely accepted financial model for justifying life-cycle investments. A theory is proposed here that can be used to value life-cycle investments in buildings. This new theory combines of real options valuation, investment analysis and building component life-cycle design. These themes are used to formulate a conceptual framework for valuing life-cycle investments. The framework is intuitive and transparent, and it can be easily added to current spreadsheet investment analysis tools. [ABSTRACT FROM PUBLISHER]

Increasing interest is being paid to the exploitation of wind power to supply stable electricity for the microgrid. The microgrid system coupled with wind turbines is available to generate power for local residents, especially in isolated areas. Being suitable for a microgrid, a 30-kW compressed air energy storage (CAES) system directly driven by a vertical axis wind turbine (VAWT) is presented in this paper. A high-pressure storage tank was used to store the compressed air in order to guarantee continuous operation. In addition, a control strategy was designed for the system to make full use of wind energy and enhance system stability. Moreover, a mathematical model was established to simulate the system with hourly wind speed data, which were randomly selected from Zibo in the Shandong province of China. Variations in gas turbine temperature, operation pressure, and the mass flow rate of compressed air with wind speed over two weeks in winter and two weeks in summer are shown in the paper. The results indicate that the adoption of the VAWT control strategy enables the round-trip efficiency to increase by 5.21% and the number of hours in the protection mode to decrease by 22 h in four weeks. Moreover, the system absorbed zthe fluctuant wind power and generated stable output (30 kW) for consumption. [ABSTRACT FROM AUTHOR]

Building cooling load prediction is of critical importance for achieving energy saving of air-conditioning system in office buildings. It not only benefits the energy-efficiency of the air-conditioning system, but is also important for the system stability. Many techniques have been developed for building cooling load prediction. These methods are normally arranged into three categories: regression analysis, energy simulation and artificial intelligence. Among them, the regression analysis methods are simple in mechanism and much practical for real application. However, traditional regression models are not sufficient to manage multi-parameter dynamic changes, and the outliers in prediction has not been well considered, making the accuracy of cooling load prediction not satisfactory. To promote the feasibility of regression methods for cooling load prediction of office buildings, an efficient regression model based on sensitivity analysis and the traditional autoregressive with exogenous (ARX) model (named as improved ARX model) is proposed in this paper. The improved ARX model keeps the constitution of ARX model, but uses specified variables that selected by sensitivity analysis. The quadratic terms of vital variables are included to reduce the impact of system non-linearity. A least square method is used to get the weight coefficient matrix for model training. Comparison studies are used to evaluate the prediction accuracy of the improved ARX model. The proposed model will largely improve prediction accuracy and more adaptive for real applications in the perspective of optimal control for HVAC systems. [ABSTRACT FROM AUTHOR]

The transition to a sustainable economy is inevitable as population and consumption continue to grow, ecosystems decline as a result of increased business activity and resources are stretched to a limit. The survival of businesses is very much dependent on their ability to adapt and transition to a business model that addresses important sustainability 'megaforces' such as climate change, energy and fuel, material resource scarcity, water scarcity, population growth, urbanisation, wealth, food security, ecosystem decline and deforestation. This research identifies megaforces that are most important to the construction industry sector and examines the level of preparedness of Australian construction companies in responding to these megaforces. It also identifies the value drivers behind these megaforces through content analysis. Recommendations are then provided for construction companies to develop resilience and remain competitive in the future. This paper will be of interest to both construction management and sustainability practitioners. [ABSTRACT FROM AUTHOR]

In this paper, a room with four inlets located at the ceiling in the centre of the room with an exhaust installed at the bottom sidewall was modelled and investigated. The air is supplied through the individual room air inlets filtered by a high-efficiency particulate air filter, and the air is removed from the room via the exhaust located at the bottom sidewall. It leads to two possible inlet arrangements with four inlets: 1 × 4 array and 2 × 2 array. In the modelling, an obstacle is built to represent a workbench located underneath the inlets. Both the array designs are compared on their air flow and ability to remove gaseous contaminants. This study also suggests that the behaviour of the air jet impingement on the surface of the obstacle must also be considered in determining the design of the inlet array in a clean room.Practical application: This paper is intended to provide a practical guide to building service engineers on the design arrangement of inlets for a Class 7 clean room. By using the same concept, the design arrangement concept can be extended to the sizing of a workbench (i.e. the obstacle) when there is a fixed inlet design. [ABSTRACT FROM PUBLISHER]

The aim of the project presented in this article was to design a system which allows for assessment of indoor environmental conditions, with a special consideration regarding the comfort of occupants. The system consists of two microprocessor devices with numerous sensors, as well as a PC application which includes fuzzy inference module. Fuzzy inference algorithm allows for comfort assessment based on data gathered by sensors. It can also help to analyse the efficiency of HVAC systems. The article includes description of the system's functions and selection criteria for sensors taking into account of measurands. Also described in this paper is the construction of knowledge base, based on information from environmental standards and experts' statements. The constructed system was tested and examined, to confirm its application in practical comfort assessment and to highlight the advantages of using fuzzy logic in the process of analysing measured parameters and inference, which captures the way living beings process data. [ABSTRACT FROM AUTHOR]

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Summary: Studies on the effect of different shape strategies on wind‐induced responses of super tall buildings have been extensive. However, little systematic research on the influence of aerodynamic shapes on wind pressure distributions of super high‐rise building having a height more than 500 m is reported in the literature. In this paper, a series of wind tunnel tests are conducted on models simulating tapered buildings taller than 500 m with an aspect ratio of 9:1 by applying synchronous pressure measurement technology to investigate the influence of different shape strategies on the wind force coefficients of the cross section (Cs) and on the peak negative pressure distributions on surfaces. The shape strategies considered include tapering of the cross section of a building along its height, chamfered modification, and opening ventilation slots. It is found that the wind force coefficient Cs increase with an increase of the tapering ratio. It is shown that chamfered modification can effectively reduce most of the wind force coefficients Cs to less than 0.9. As for peak wind pressures, a zone having a higher negative pressure is found to locate at the bottom of the side faces of the model. With an increase of the tapering ratio, the peak negative pressure of side faces of the model slightly decreases. Chamfered modification can significantly increase the peak negative pressure at the chamfered location. Furthermore, it is demonstrated that opening ventilation slots had less effect on Cs, but the peak negative pressure can significantly increase at the area of opening ventilation slots and adjacent areas. [ABSTRACT FROM AUTHOR]

Refurbished buildings should also increase their energy efficiency, according with current regulation; however, in case of historical buildings, preservation orders are so strict to hamper usual energy efficient interventions on the building envelope side. As a consequence, in historical buildings, HVAC (Heating, Ventilation and Air-Conditioning) systems and control strategies should be further improved, since they are the only true means for energy efficiency. This paper presents the set of technologies implemented in the frame of the refurbishment of an historical building in the very center of Venice, in order to lower energy consumption and increase occupants’ comfort. The refurbishment consisted mainly in the application of the following technologies: Surface Water Heat Pump (SWHP), Demand Controlled Ventilation (DCV) and trigeneration. Furthermore, the paper proves the achieved energy savings by comparing the actual energy consumption against detailed building energy simulations for baseline HVAC system configurations. For such a purpose, the authors take advantage of the installed extensive building management system (BMS), which is able to record detailed data about flow rates (of air and water), temperature and humidity for all of the key devices of the HVAC system. The building used as a case study is very significant because of its energy intensive intended use as well as for the very strict preservation orders acting on it. In particular, global primary energy savings equal to 36% have been calculated, if compared with a traditional baseline HVAC system. [ABSTRACT FROM AUTHOR]

Analysis of wind flow acting upon high-rise buildings is a very common topic. This paper deals with experiment in the Boundary Layer Wind Tunnel (BWLT) in Bratislava and comparison with the computational fluid dynamics (CFD) simulation and values given in the Eurocode. The analyzed object was the model of building with circular cross section (cylinder). External wind pressure coefficients were compared in three height levels of model. [ABSTRACT FROM AUTHOR]

This paper intends to establish a model for the service life prediction of natural stone claddings with indirect fastening system based on a survey of the degradation state of 142 buildings in the Lisbon area. The state of degradation is evaluated through visual inspections that allow describing the extent of the cladding area affected by the different anomalies, thereby enabling the level of severity of the anomalies detected to be established. A numerical index of the degradation severity of stone claddings (Sw) is established; this is intended to express the global degradation level of these claddings, thus allowing the study of the evolution of their degradation with time to estimate a reference service life of this type of cladding. The results achieved in this study allow analyzing the influence of some intrinsic and extrinsic characteristics on the durability and service life of natural stone claddings with indirect fastening system. The information provided by the proposed models is essential for the definition of maintenance strategies, promoting a rational and sustainable management of the built heritage, optimizing the use of resources, and minimizing the overall cost of the building over its lifecycle. [ABSTRACT FROM AUTHOR]

The need for technological and administrative innovation is a recurrent theme in the UK construction-reform agenda, but generic improvement recipes are beginning to give way to a more focused prescription: building information modelling (BIM). The current strategy is to mandate the use of BIM for government projects as a way of integrating the design, construction and operation of publicly procured buildings. This aspiration represents a partial turn away from a focus on managerialist agendas towards a belief in the power of digital practices to achieve the aspiration of integrated working, collaboration and innovation, a trend that is being reflected globally in relation to both national and firm-level policy interventions. This paper subjects this so-called ‘BIM revolution’ to critical scrutiny. By drawing on theories of the digital divide, a critical discourse is developed around the ways in which political reform agendas centred on BIM might not stimulate innovation on a wider scale, but could act to disenfranchise small firms that are unable (or unwilling) to engage with them. This critical analysis presents important new research questions around the technocratic optimism that pervades the current reform discourse, the trajectory of industry development that it creates and the policy process itself. [ABSTRACT FROM PUBLISHER]

Clustering algorithms have been successfully applied in analyzing building energy consumption data. It has proven to be an effective technique to identify representative energy consumption patterns as well as being a pre-processing step for other techniques. In this paper, we propose a clustering method based on k-shape algorithm, which is a relatively novel method to identify shape patterns in time-series data. In the experiment, clustering is performed for each individual building according to its hourly consumption. The novelty of this paper is that a new k-shape algorithm is applied to detect building-energy usage patterns at different levels, and the clustering result is further utilized to improve the accuracy of forecasting models. Ten institutional buildings covering three different typologies are used as case studies and a set of hourly and weekly energy consumption data is further analyzed in this paper. The experimental results reveal that this proposed method can detect building energy usage patterns in different time granularity effectively and also proves that the forecasting accuracy of SVR model is significantly improved by utilizing the results of the proposed clustering method. [ABSTRACT FROM AUTHOR]

Concerning the building environment HVAC facilities, even if a great effort has been made in developing components and systems with high nominal efficiencies, less attention has been paid to the problem of system maintenance. The main objective of the thermoeconomic diagnosis is to detect possible anomalies and their location inside a component of the energy system. The second objective, and indeed the one to be achieved in this paper, is indicated as inverse problem. It is associated with the quantification of the effects of anomalies in terms of thermoeconomic quantities. Its rigorous application in building thermal installations has some difficulties relating to the strong interrelation between the different components and the fact that energy supply facilities are continuously changing with time. The way to deal with dynamic circumstances is thoroughly explored in this article. Likewise, this paper’s main goal is to demonstrate an application of two thermoeconomic diagnosis methodologies in the building sector, one based on the malfunction and dysfunction analysis and the other one based on the characteristic curves of the components. The results obtained allow us to point out the advantages and limitations of both methodologies as well as to combine them and then develop a more reliable diagnosis. [ABSTRACT FROM AUTHOR]

Engineering research is undergoing dramatic changes with novel, large-scale research facilities being developed to help reduce the growing economic losses associated with natural disasters. The wall of wind (WOW), at Florida International University (FIU), is such an experimental facility, capable of simulating hurricane winds and wind-driven rain to better understand hurricane effects on buildings and other infrastructure. The WOW has been designated by the national science foundation (NSF) as one of the experimental facilities (EFs) under the natural hazards engineering research infrastructure (NHERI) program, which aims to allow researchers to enable innovations and help prevent natural hazards from becoming societal disasters. The WOW EF's goal is to facilitate research to improve design practices for structural systems, building envelopes, and lifeline infrastructure. This paper presents an overview of the design and development of the WOW research facility and delineates its capabilities to assess and mitigate the impacts of hurricane wind, rain, and debris on civil infrastructure. Advantages and limitations of the facility are explained. To illustrate the EF's research capabilities, details and results from three recent case studies related to large-scale and full-scale testing of building components and traffic infrastructure are described. [ABSTRACT FROM AUTHOR]

This paper describes experimental investigations of fire service ventilation and suppression practices in full-scale residential structures, including a one-story, 112 m, 3 bedroom, 1 bathroom house with 8 total rooms and a two-story 297 m, 4 bedroom, 2.5 bathroom house with 12 total rooms. The two-story house featured a modern open floor plan, two-story great room and open foyer. Seventeen experiments were conducted varying fire location, ventilation locations, the size of ventilation openings and suppression techniques. The experimental series was designed to examine the impact of several different tactics on tenability: door control, vertical ventilation size, and exterior suppression. The results of these experiments examine potential occupant and firefighter tenability and provide knowledge the fire service can use to examine their vertical ventilation and exterior suppression standard operating procedures and training content. It was observed that door control performed better at controlling the thermal exposure to occupants than did fully opening the door. Additionally, the impact of increased vertical ventilation area was minimal, and only slightly reduced the thermal exposure to occupants in a few non-fire rooms. In the two-story structure, the non-fire rooms on the second floor consistently had larger thermal fractional effective rate (FER) values (approximately 2.5× the thermal risk to oocupants) than did the non-fire rooms on the first floor. Water application was also shown to reduce the thermal risk to occupants 60 s after water application 1/3rd the original values on second floor rooms of the two-storry structure and by at least 1/5th of the original values on the first floor rooms of both structures. Data also showed that the impact of front door ventilation on the toxic gases exposure was minimal, as the toxic gases FER actually increased after front door ventilation for several experiments. However, after vertical ventilation there was a 30% reduction in the toxic gases exposure rate in two of the one-story structure experiments. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this paper is to present a tool for simulating heat sharing opportunities between multiple buildings.Design/methodology/approach The approach is based on a building simulation model, HAMBase, in combination with an analytical programming code using MatLab.Findings The tool provides a quick insight in possibilities for district heat sharing. It is able to operate without using too many parameters. From the results, it can be derived that storage tanks provide a great advantage in performance over the direct heat demand and supply method.Research limitations/implications The main limitations are as follows: the used models are based on assumptions plus values derived from literature and a verification that is based on energy balance rules; and the MatLab code is verified by checking for possible errors, but is not completely validated.Originality/value The main value of the work is that the presented methodology behind the tool is generally applicable and implementable in other models. [ABSTRACT FROM AUTHOR]

This paper compares smart control models for heating supply air among five different climate conditions to discuss the effectiveness of machine learning tools in terms of control and energy efficiency. A thermostat on/off control is typically used to maintain room temperature at a desired level. Advanced computing technologies have recently been introduced to complement the conventional on/off controls to improve control efficiency in heating systems. However, these methods, which were mostly utilized to control fuel amount or fan motor speed, lacked the capability to promptly respond to various outdoor temperature conditions as climate zones requiring refined control strategies to reduce environmental impacts. This paper proposes intelligent controls of mass and temperature simultaneously for heating air supply. The Fuzzy Inference System (FIS) and Artificial Neural Network (ANN) algorithms are utilized to develop six control models, and the models are tested to evaluate both control and energy efficiency during the winter season in five climate zones (from climate zone 2 through 6; i.e., Houston, Dallas, Raleigh, Chicago, and Detroit, respectively). Results include the energy consumption, control errors, and control signals in comparison to the baseline on/off control, which confirms the fact that the ANN simultaneous controls of mass and temperature is more effective than the other controllers for control accuracy and energy savings by 71.3% and 0.3%, respectively. The effectiveness of the ANN controller can contribute to maintaining room temperature accompanying the reduction of energy consumption, which is directly related to improve human comfort and reduce environmental impacts in various climate zones. [ABSTRACT FROM AUTHOR]

This paper presents an online transfer learning framework for improving temperature predictions in residential buildings. In transfer learning, prediction models trained under a set of available data from a target domain (e.g., house with limited data) can be improved through the use of data generated from similar source domains (e.g., houses with rich data). Given also the need for prediction models that can be trained online (e.g., as part of a model-predictive-control implementation), this paper introduces the generalized online transfer learning algorithm (GOTL). It employs a weighted combination of the available predictors (i.e., the target and source predictors) and guarantees convergence to the best weighted predictor. Furthermore, the use of Transfer Component Analysis (TCA) allows for using more than a single source domain, since it may facilitate the fit of a single model on more than one source domain (houses). This allows GOTL to transfer knowledge from more than one source domain. We further validate our results through experiments in climate control for residential buildings and show that GOTL may lead to non-negligible energy savings for given comfort levels. [ABSTRACT FROM AUTHOR]

This paper shows the environmental planning and evaluation of an office with a funnel shaped void which was constructed in 2012 in Osaka, Japan. The design theme of this pharmaceutical company's office building was “an office for a healthy future”- architecture that is healthy for both the global environment and users. The design aimed at creating an office building with low energy consumption that makes maximum use of natural conditions. An open-air atrium stretching from the first basement level to the roof was provided in the center of the building. The building is also provided with greenery on upper floors, mist spraying equipment, natural ventilation windows, a terrace for relaxation, etc. in an effort to reduce energy consumption and create a healthy and appealing environment. This paper first explains the design conditions and concept of this office building, and then discusses the design approaches. Lastly, it evaluates the effect on the basis of the actual measurement data. The introduction of energy-saving technology achieved a significant reduction of the primary energy and CO 2 emissions throughout the building. [ABSTRACT FROM AUTHOR]

The two spaces office module is usually considered as a representative case-study to analyse the energetic improvement in office buildings. In this kind of buildings, the use of a model predictive control (MPC) scheme for the climate system control provides energy savings over 15% in comparison to classic control policies. This paper focuses on the influence of solar radiation on the climate control of the office module under Belgian weather conditions. Considering MPC as main climate control, it proposes a novel distributed enhanced control for the blind system (BS) that takes into account part of the predictive information of the MPC. In addition to the savings that are usually achieved by MPC, it adds a potential 15% improvement in global energy use with respect to the usually proposed BS hysteresis control. Moreover, from the simulation results it can be concluded that the thermal comfort is also improved. The proposed BS scheme increases the energy use ratio between the thermally activated building system (TABS) and air-handling unit (AHU); therefore increasing the use of TABS and allowing economic savings, due to the use of more cost-effective thermal equipment. [ABSTRACT FROM AUTHOR]

This paper reviews occupancy based model predictive control (MPC) for building indoor climate control. Occupancy behavior in buildings is stochastic and complex in nature. With better understanding of occupancy presence in rooms and spaces, advanced controls, such as MPC, can be designed to achieve a more energy efficient operation, compared to more traditional control methods, while comfort is maintained. This paper starts with an overview of traditional controls implemented in buildings, and importance of occupancy based controls. Various control-oriented building modeling methods including physics-based and data-driven models are reviewed. Later on, a comprehensive review of MPC in terms of control theory, objective functions, constrains, optimization methods, system characteristics and various types of MPC is presented conducted. In principle, MPC finds an optimal sequence of control commands to optimize an objective function, considering system model, disturbances, predictions and actuation constraints. Lastly, occupancy based controls including commonly used rule-based and latest model-based controls are reviewed. In addition, a few experimental studies are presented and discussed. The paper presents a holistic overview of occupancy-based MPC for building heating, ventilation, and air conditioning (HVAC) systems, and discusses current status and future challenges. The purpose of this paper is to provide a guideline forresearchers who would like to conduct similar studies to have a better understanding of established research methods. [ABSTRACT FROM AUTHOR]

The construction industry is responsible for more than 40% of the carbon emissions in the United States. These emissions are generated by energy, water, and materials consumed at different stages of the construction, maintenance, operation, and disposal processes and during the recycling and reusing of construction components as materials or biomass. Carbon-emission modeling is a complex procedure of process and footprint integration for different components either directly and indirectly associated with a service, product, material, or system at different phases. Prior research focused on each phase separately and/or supplemental information from alternative sources because of the lack of available data and information. Even though there are comprehensive lifecycle models covering every phase of a project, these models do not integrate existing models. The purpose of this study was to develop a comprehensive framework of building lifecycle carbon-emission modeling that would integrate existing models, information, and data. This research integrated prior models and methods, incorporated multitier mechanisms, and developed flexibility within the model so that reliability would be improved for measuring, tracking, and quantifying carbon- and environmental-related features, factors, and variables. This paper discusses the first phase of the research, model development, and testing. [ABSTRACT FROM AUTHOR]

The paper is focused on degradation caused by microorganisms, a process called biodegradation, and on risks for human health caused by them. Bacteria and algae are the primary microorganisms on external building surfaces. These pioneer microorganisms have an enriched space of organic carbon, which is necessary for the growth of any subsequent microorganism which is often mold. Biodegradation is a synergic process of chemical reactions (chemical biodegradation) and physical effects of microbial bodies on building materials (biophysical degradation). The paper is a summary of the current state of art and knowledge in the field of biodegradation. [ABSTRACT FROM AUTHOR]

The thermal performance of the building envelope is of critical importance to the overall building performance. This paper presents an investigation of the influence of most common attic typologies used in Portuguese housing stock on heating/cooling loads of conditioned spaces under different weather conditions. Unused attics are part of the building envelope, which provide protection from the external environment acting as a buffer space. To improve this protective ability, some scenarios such as insulation, low emissivity, ventilation and the slant of the roof are considered. The aim of this study is to assess the influence of such scenarios by investigating through simulating the heat transfer between the attics and spaces underneath. The extent to which an improved attic steers towards low energy buildings is established where a dynamic Ud-values can be as low as 0.15 W/(m2K) and the yearly thermal reduction may surpass 20%. [ABSTRACT FROM AUTHOR]

This publication is considered the most promising path leading to the creation of energy-efficient engineering solutions for various buildings. This path begins with the first design calculations. The foundation for creating cost-effective heating and ventilation systems is carried out at the stage of forming the heat and mass balances of the premises as building components. Besides drawing the heat and mass balances must be closely connected with the study of the geometric parameters of premises and the thermal performance of the building envelope. In this paper a special way of heat load computing of heating and ventilation systems is considered. It is shown that considered method allows refining the calculations of heat losses of the building. The application of the proposed method to determine the transmission heat losses with the elemental approach is considered. The calculating method of ventilation heat losses with different variations of accounting the infiltration component is shown. Way of the joint account of heat energy consumption factors in a single mathematical apparatus is presented. The method of optimizing of heat loads during extreme operating conditions is reviewed. The paper shows further way application of accurate method in the design of buildings and the results of calculations. Some conclusions are suggested as a conclusion of this article. [ABSTRACT FROM AUTHOR]

Construction professionals are required to integrate environmental concerns in the earliest design phases. However, environmental assessments need large amounts of precise data that are typically not available in the early design process, as most variables are still fluid. To address this concern, a new approach explores how environmental information on building components can be simplified for strategic use early in the design process in a Danish context. In this paper, life cycle assessments (LCAs) are undertaken for several hundred typical external wall solutions, based on relevant standards. A full bivariate linear regression analysis is performed, showing statistically significant correlations with strong direct relationships between environmental impact categories. A simplified LCA profile consisting of total primary energy, global warming potential and acidification potential is developed. This simplified LCA profile presents environmental data in a more understandable way, creating a strategic overview that can be easily used by non-technical clients and construction professionals in the early design stages. This has a scientific and statistical validity generated by environmental assessment standards, and creates a parallel between the precision of the approach and its time of use in the design process. [ABSTRACT FROM PUBLISHER]

The comfort zone is bounded by thermal environmental conditions that may be described as acceptably cool or acceptably warm, and engineering out of existence these innocuous thermal conditions on the fringes of the adaptive comfort range may not be necessary. In contrast to the conventional understanding of local discomfort, spatial alliesthesia exploits corrective differences in the rate of change in skin temperature between individual body segments to elicit positive affective sensations. This paper examines reverse instances of local discomfort, or spatial alliesthesia, from warm contact stimuli applied to hand and feet when exposed to ambient conditions towards the lower margin of the comfort zone. It was found that subjects with moderate feelings of displeasure or even indifference were still capable of experiencing a pleasant response to localized thermal stimuli. Brief whole-body thermal pleasure was observed fromin-situskin temperature changes at a single distal body site. These effects were subtle and not universally experienced, so the success of their deliberate implementation in built environments depends heavily on some form of individual control. Spatial alliesthesia therefore complements the body of literature investigating personal environmental control and local thermal discomfort by providing a theoretical framework of thermal perception in non-neutral environments. [ABSTRACT FROM PUBLISHER]

The goal of this paper is to identify the effects of in-pore transport of liquid water and water vapor as well as phase changes on the hygrothermal behavior of earthen buildings. Indeed, one of the main assets used to promote these constructions is their role in moisture buffering hence temperature and relative-humidity quality controlling. However, there is no clear consensus yet concerning the impact of these phenomena on the global energy performance of the buildings. A coupled model is therefore proposed in this paper, based on heat and mass balances inside the earthen walls, in order to clarify this question. This model considers separately the kinematics of each phase (e.g. liquid water, vapor, dry air and solid matrix), in interaction with each other. It also takes into account the impact of pore water confinement on the liquid-to-vapor phase change, in particular on the resulting latent heat released or absorbed. The model is successfully compared to experimental results on instrumented full-scale rammed earth wall subjected to temperature cycles. It eventually allows identifying the singular hygrothermal behavior of earth material by testing the range of applicability of the simplifying assumptions which are commonly made in function of the permeability of the tested material. [ABSTRACT FROM AUTHOR]

The smart grids are modern electric power grid infrastructure for enhanced efficiency and reliability through automated control, high-power converters, modern communications infrastructure, sensing and metering technologies, and modern energy management techniques based on the optimization of demand, energy and network availability. The role of buildings in this framework is very crucial. This paper addresses critical issues on smart grid technologies and the integration of buildings in this new power grid framework. The main objective of this paper is to provide a contemporary look at the current state of the art in the potential of buildings and communities to be integrated in smart grids as well as to discuss the still-open research issues in this field. The challenges for the building sector are discussed and future research prospects are analysed. [ABSTRACT FROM AUTHOR]

The design community lacks simple, data-driven energy assessment tools to explore energy-efficient alternatives during the early stages of building design. A promising option is to utilize a whole building energy simulation engine (e.g. EnergyPlus) within a Monte Carlo simulation framework to develop a linear regression-based building energy model (LRBEM) that can predict idealized heating and cooling loads based on parameters relevant to early design. Previous work was limited to medium-sized US commercial office buildings with rectangular geometries. A key limitation is addressed in this paper by considering complex geometries. A reformulated model, LRBEM+, is developed and tested with a suite of building geometries that represent limiting cases. The resultant relative error between LRBEM+ and EnergyPlus is generally less than 10%. Furthermore, LRBEM+ correctly predicts the direction and magnitude of changes in heating and cooling loads in response to changes in the most influential early design parameters. [ABSTRACT FROM PUBLISHER]

This paper presents an innovative method for modeling energy hubs based on energy flow between its constituent elements. Using this method, modeling of energy hubs with different elements and connections is facilitated. Also, an appropriate mixed integer nonlinear programming model is presented for short term 24-hour scheduling an energy hub, in which, the objective is to fulfill daily cooling, heating and electric demands of a hypothetical building with the maximum profit. Furthermore, in the energy flow based modeling method presented in this paper, energy storage elements are not only used at the output of the hub; but also, are capable of being used as inputs for other elements inside the energy hub. In order to evaluate the performance of the model, simulations have been accomplished for one hot and one cold typical day. Presented energy hub includes various elements such as combined heat and power, electric heat pump, boiler, absorption chiller and electrical and thermal energy storages. Moreover, in the modeling of the proposed energy hub, feasible operation region for combined heat and power system together with technical constraints of energy hub equipment is considered. Analyzing numerical results, flexibility of the energy hub for feeding the required loads of the building, operation of combined heat and power and the effect of electrical heat pumps in meeting cooling and heating loads of the building are evaluated. The numerical results show that combined heat and power operation points and its average electrical and thermal efficiency in hot and cold days are totally different and electric heat pump, regarding its high efficiency, is the main supplier of cooling and heating loads of the building in the studied energy hub. [ABSTRACT FROM AUTHOR]

This paper presents an algorithm to translate building topology in an object-oriented architectural building model (Building Information Modeling, BIM) into an object-oriented physical-based energy performance simulation by using an object-oriented programming approach. Our algorithm demonstrates efficient mapping of building components in a BIM model into space boundary conditions in an object-oriented physical modeling (OOPM)-based building energy model, and the translation of building topology into space boundary conditions to create an OOPM model. The implemented command, TranslatingBuildingTopology, using an object-oriented programming approach, enables graphical representation of the building topology of BIM models and the automatic generation of space boundaries information for OOPM models. The algorithm and its implementation allow coherent object-mapping from BIM to OOPM and facilitate the definition of space boundaries information during model translation for building thermal simulation. In order to demonstrate our algorithm and its implementation, we conducted experiments with three test cases using the BESTEST 600 model. Our experiments show that our algorithm and its implementation enable building topology information to be automatically translated into space boundary information, and facilitates the reuse of BIM data into building thermal simulations without additional export or import processes. [ABSTRACT FROM AUTHOR]

This paper investigated a novel loop-heat-pipe based solar thermal heat-pump system for small scale hot water production for household purposes. The effective use of solar energy is hindered by the intermittent nature of its availability, limiting its use and effectiveness in domestic and industrial applications especially in water heating. The easiest and the most used method is the conversion of solar energy into thermal energy. We developed a prototype solar water heating system for experimental test. We reported the investigation of solar thermal conversion efficiency in different seasons which is 29.24% in summer, 14.75% in winter, and 15.53% in rainy season. This paper also discusses the DC heater for backup system and the current by using thermoelectric generator which are 3.20V in summer, 2.120V in winter, and 1.843V in rainy season. This solar water heating system is mostly suited for its ease of operation and simple maintenance. It is expected that such novel solar thermal technology would further contribute to the development of the renewable energy (solar) driven heating/hot water service and therefore lead to significant environmental benefits. [ABSTRACT FROM AUTHOR]

In this paper, we examine the influence of branding a building as LEED certified on occupants' pro-environmental behavior (individual participation in an activity that promotes sustainable (green) practices by reducing or eliminating negative environmental impacts). Branding is defined as identifying a building as LEED certified and emphasizing the aspects of the building's green features to its users. One hundred participants were randomly assigned to one of the two experimental groups: (1) the branding group, in which the building was branded as being LEED certified, and (2) the control group, in which no information was provided about the building being LEED certified. Through the use of an immersive virtual environment, two examples of pro-environmental behaviors were examined between the two groups: participants' choices in using natural light vs. artificial light for increasing the lighting levels in the room, as well as their choices of recycling bin vs. regular trashcan for placing scrap paper. The results show that the participants in the branding group chose natural light and recycling bin significantly more than the participants in the control group, suggesting that LEED branding motivates occupants' pro-environmental behaviors. The results also show that participants' environmental values and views had significant effects on the influence of LEED branding. The results also suggest that increasing building occupants' knowledge about environmental issues might improve their pro-environmental behaviors. [ABSTRACT FROM AUTHOR]

Indoor air quality (IAQ) and energy consumption are becoming increasingly important in the HVAC field. This paper examines the potential of improving demand-controlled ventilation (DCV) performed under an occupant based ventilation standard. CO2-based DCV and radio frequency identification-based DCV methods are simulated in an office building model served by a dedicated outdoor air system combined with a fan-coil system. A numerical model for estimating real-time occupancy is developed. Simulations are conducted with current Chinese ventilation standard as an example. Results show that the current standard causes severe fluctuations under a CO2-based DCV strategy. It is concluded that the current standard defines the ventilation rate as a function only related to the occupancy number, which makes DCV control unstable. As an improvement, the current Chinese ventilation standard is modified to a form similar to the standard of the American Society of Heating, Refrigerating and Air-Conditioning Engineers that considers the occupant and the building separately. The modified standard is applicable to various DCV approaches and can maintain an acceptable formaldehyde concentration. This modification significantly improves the applicability of the current Chinese ventilation standard to CO2-based DCV and can be easily extended to similar ventilation standards. [ABSTRACT FROM AUTHOR]

This paper address the accusation that traditional buildings are energy inefficient, particularly with regard to the heat loss of solid walls. It compares measured and calculated U-values for these solid walls and discusses the discrepancy found between them, where measured U-values identify lower heat loss than conventional estimates. The paper looks at the implications of this with regard to broader energy assessment methods and how this may reconfigure assumptions of energy performance for traditional buildings. It also seeks to explain the importance of accurate heat loss assessment for solid walls in relation to retrofitting or refurbishment, particularly in the light of risks from moisture. [ABSTRACT FROM AUTHOR]

This paper introduces a methodology that makes use of laser Doppler vibrometry to assess the acoustic insulation performance of a building element. The sound power radiated by the surface of the element is numerically determined from the vibrational pattern, offering an alternative for classical microphone measurements. Compared to the latter the proposed analysis is not sensitive to room acoustical effects. This allows the proposed methodology to be used at low frequencies, where the standardized microphone based approach suffers from a high uncertainty due to a low acoustic modal density. Standardized measurements as well as laser Doppler vibrometry measurements and computations have been performed on two test panels, a light-weight wall and a gypsum block wall and are compared and discussed in this paper. The proposed methodology offers an adequate solution for the assessment of the acoustic insulation of building elements at low frequencies. This is crucial in the framework of recent proposals of acoustic standards for measurement approaches and single number sound insulation performance ratings to take into account frequencies down to 50 Hz. [ABSTRACT FROM AUTHOR]