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Energy-based seismic evaluations of structures can give clear illustrations of seismic demands made upon structures. This paper presents a 3-dimensional energy-based modal pushover analysis (3D EMPA) method with equivalent three degree of freedom (ETDOF) system and equal-displacement rule. The lateral-rotational coupled effect on structures asymmetric in plan is considered using the energy-based modal pushover analysis (EMPA), which is more robust than the traditional Modal Pushover Analysis (MPA) procedure. The proposed procedure was validated against a nonlinear time history analysis of a 5-storey structure. The results show that the method is able to take higher mode effects into account and that the instability of capacity spectra will be avoided. The maximum deformation obtained from EMPA shows good agreement with a nonlinear time history analysis results of the original system. The proposed EMPA procedure appears to be reliable and effective for evaluating the seismic response of asymmetric-plan structures. [ABSTRACT FROM AUTHOR]

The article offers an update on the activities of the "Journal of Building Physics" as of April 2010, including an expression of gratitude for a number of individuals who assisted the journal in the review process.

This paper reviews the literature on passive building design for improving indoor thermal comfort in tropical climates through a bibliometric analysis. The Web of Science database and CiteSpace were searched, and 722 articles were selected and analyzed to form the body of this article. An overview of the evolution of publications from 1984 to 2021 is first presented, followed by an examination of the co-citation networks of journals, countries, keywords, documents and authors. Co-occurrence analysis of 391 keywords, 861 highly cited publications and the top 15 most frequently mentioned publications and most salient were used to identify research methodologies and to analyze the correlation search of articles. Some notable work on thermal comfort models and passive design strategies suitable for a warm climate is also discussed. The results show that real-time field studies compared to dynamic simulations represent the most outstanding research on passive design and thermal comfort of buildings in tropical climates. In addition, standards such as ASHRAE Standard 55 and ISO Standard 7730 have played an essential role in the evolution of the subject. The results of this study may inspire other researchers and policy makers. [ABSTRACT FROM AUTHOR]

Our paper investigates how an institution can be maintained over a long period of time through adaptations to the material artefact which instantiates it. To illustrate our argument, we conduct a historical case study of the Guimard Metropolitan railway entrances, a material artefact which instantiates the Belle Epoque institution from 1914 to 2000. Based on our findings, we develop a process model of institutional maintenance based on the malleability of a material artefact. Supported by three types of interrelated institutional work – damage, preservation and transferability work – we illustrate how adaptations to the material form, meaning and location of an artefact allow an institution to address the evolving environment and its associated challenges and thus to be maintained over time. Our study expands our understanding of long-term institutional maintenance by capturing the importance of the malleability of an artefact and in offering a more positive view on damage work. It also has some implications for studies on materiality in highlighting the multidimensionality of artefacts and the role of transferability and relocation. [ABSTRACT FROM AUTHOR]

The article calls for papers for the Building Enclosure Science and Technology (BEST) Conference in Nanjing 2010 in China and announces the selection of Ardeshir Mahdavi and Marc Olivier Abadie as new members of the editorial board of the "Journal of Building Physics."

Innovations in materials, construction techniques and technologies in building construction and refurbishment aim to reduce carbon emissions and produce low-energy buildings. However, in-use performance consistently misses design specifications, particularly those of operational energy use and indoor environmental quality. This performance gap risks reducing design, technology, sustainability, economic, health and well-being benefits. In this paper, we compare settings of the Chinese and the UK buildings sectors and relate their historical context, design, construction and operation issues impacting energy performance, indoor environmental quality, occupant health and well-being. We identify a series of key, common factors of 'total' building performance across these two settings: the application of building regulations, the balance between building cost and performance, skills, construction and operation. The dynamic and complex interactions of these factors are currently poorly understood and lead to building performance gaps. We contend that a systems approach in the development of suitable building assessment methods, technologies and tools could enable the formulation and implementation of more effective policies, regulations and practices. The paper illustrates the application of the approach to the UK and Chinese settings. A full application of a systems approach may help to provide a more dynamic understanding of how factor interactions impact the 'total' building performance gaps and help address its multiple causes. [ABSTRACT FROM AUTHOR]

Between 1990 and 1998, the author published five conference papers which described the gradual development of a simple theoretical model for predicting the sound insulation of building partitions. The first aim was to extend Sharp's model for cavity walls to cavities without sound absorption. The second aim was to remove the reported over prediction of Sharp's model for cavity walls. The third aim was to explain the five decibel empirical correction in Sharp's model for stud walls. The fourth aim was to produce a more theoretically valid model than Gu and Wang's steel stud wall model. Although the simple theoretical model has been reasonably successful, several concerns have since arisen. This paper describes how these concerns have been addressed and gives the current version of this theoretical model for predicting sound insulation. The theoretical model is compared with a number of experimental measurements and produces reasonable agreement. [ABSTRACT FROM AUTHOR]

This paper is the fifth in a series of papers outlining a holistic model of atmospheric corrosion. Previous papers have outlined how the airborne salinity could be estimated at any given location. This paper presents a theoretical analysis of aerosol/particulate deposition, in conjunction with computational fluid dynamics (CFD) studies. Theoretical and CFD studies address whether salt aerosol/particulate deposition is controlled by mean winds, wind turbulence or Brownian motion (deposition of salt via rain/fog etc. is not considered in this paper). Analysis indicates that deposition due to wind turbulence is the dominant mechanism for marine aerosol, and that other deposition modes can be effectively ignored. Given this, further studies are presented for salt candles, plates and buildings. From these studies, approximations are derived so that salt deposition on exposure plates and on buildings can be estimated from measurements from ISO salt candles. [ABSTRACT FROM AUTHOR]

This paper draws on assemblage thinking—especially Deleuze and Guattari’s conception of territorialization—to analyze urban redevelopment processes in Oklahoma City, a mid-sized city in the central United States that has pursued a culturally led, “entrepreneurial” approach to redevelopment. Focusing on the linkages between architecture, sport, and local food in the city, I demonstrate some of the ways in which these realms were woven together in support of the territorial expansion of redevelopment. Following recent research on affect in human geography, I argue that the interweaving of these realms involved careful attention to the material capacities of buildings, athletic bodies, and foods to generate a sense of excitement, pride in place, self-worth, and above all movement in the city. The paper concludes with a discussion of some of the implications of this analysis for the politics of redevelopment and some suggestions for future research. [ABSTRACT FROM AUTHOR]

This paper explores the development of green entrepreneurship and its potential role in transformative change towards a green economy. It achieves this through a study of the green building sector in England and Wales, based on qualitative empirical data from fifty-five semistructured interviews with businesses in the green building sector and with support organisations, including banks, financial sources, and business advice and support. The paper both critiques and synthesises two bodies of literature-- entrepreneurial research and sociotechnical transitions theories, specifically the multilevel perspective (MLP)--to better understand the role of green entrepreneurs in facilitating a shift towards a green economy. This analysis embeds green entrepreneurs in a wider system of actors, rather than reifying the lone entrepreneurial hero, in order to explore how green entrepreneurs facilitate sustainability transitions. The paper challenges the notion that green entrepreneurs are an unproblematic category. We discovered that individuals move between 'green' and 'conventional' business, evolving over time, such that this is a fluid and blurred, rather than static, state. Moreover, while the green economy and the green building sector are often referred to as coherent sectors, with agreed and consistent practices, our evidence suggests that they are far from agreed, that business models vary, and that there are significant contradictions within so-called green building practices. The paper contributes to the development of sociotechnical transitions theory and suggests that the MLP needs to incorporate complexity and multiplicity within niches, that niches may be inherently conflictual rather than consensual, and that the concept of 'protection' for niches is problematic. [ABSTRACT FROM AUTHOR]

Since 3D city models need to be realistic not only from a bird's point of view, but also from a pedestrian's point of view, the interest in the generation of 3D façade models is increasing.This paper presents two successive algorithms for automatically segmenting building façades scanned by Terrestrial Laser Scanner (TLS) into planar clusters and extracting their contours. Since majority of façade components are planes, the topic of automatic extraction of planar features has been studied.The RANSAC algorithm has been chosen among numerous methods. It is a robust estimator frequently used to compute model parameters from a dataset containing outliers, as it occurs in TLS data. Nevertheless, the RANSAC algorithm has been improved in order to extract the most significant planar clusters describing the main features composing the building façades. Subsequently, a second algorithm has been developed for extracting the contours of these features.The innovative idea presented in this paper is the efficient way to detect the points composing the contours. In order to evaluate the performances of both algorithms, they have successively been applied on samples with different characteristics, i.e. densities, types of façades and size of architectural details. Finally, a quality evaluation based on the comparison of planar clusters and contours obtained manually has been carried out.The results prove that the proposed algorithms deliver qualitative as well as quantitative satisfactory results and confirm that both algorithms are reliable for the forthcoming 3D modelling of building façades. [ABSTRACT FROM AUTHOR]

This paper proposes the Audit, Control and Monitoring Design Patterns (ACMDP) for building Autonomous and Robust Systems (ARS) such as Mobile Robot Systems (MRS). These patterns are also applicable to other Mission Critical and Complex Systems (MCCS). This paper presents a proposal which will help ARS project managers and engineers design, build and estimate the probability that an ARS will succeed or fail. Furthermore, this proposal offers the possibility to ARS problems with the help of audit, monitoring and controlling components, adjust the project management pathways, and define the problem sources as well as their possible solutions, in order to deliver an ARS or an MRS. [ABSTRACT FROM AUTHOR]

From ancient times, the traditional architectural practice 'Vastusastra' is rigidly followed and practised in many parts of the Indian sub-continent and has a unique position in Indian architecture. In Indian traditional domestic architecture, a hand calculator table and an index number system are used for finding the proportion and orientation of the building. The mathematical and logical background of this traditional practice, which is not known at present, is investigated in this paper. The study reveals that there is a strong and complex mathematical background behind this traditional architectural practice. [ABSTRACT FROM AUTHOR]

Glass façade systems in buildings are subject to racking actions caused by inter storey drifts from earthquakes and wind action. The performance of façade systems is dependent on the amount of imposed drift and the interaction of the glass panels with the façade structural support frames. There are two major concerns related to the glass façade system performance during and immediately after a seismic event; hazards to people from falling glass and the cost associated with building down time and repair. It was observed that earthquake damage to glass façade systems resulting from in-plane racking actions is increasingly common and yet there has been limited research published in this field. The research completed to date has mainly focused on traditional framed glass façade systems; however, the racking performance of point fixed glass façade system (PFGFS) is likely to be quite different. Therefore, the aim of the research presented in this paper is to assess the in-plane racking performance of PFGFS which is a façade system gaining popularity worldwide.Two unique full scale in-plane racking laboratory tests on typical PFGFS with different types of connections were conducted and specific racking mechanisms were identified. Sophisticated non-linear finite element models (FE models) were developed and benchmarked against experimental results with excellent correlation. Further detailed FE analyses were conducted to evaluate the individual drift contributions of each racking mechanism such as rigid body translation of the glass panels at the oversize holes for construction tolerance, spider arm rotation and spider arm deformation. It was found that most of the drift capacity is attributed to the rigid body translation at the oversize holes. In this paper, the laboratory test setup and the experimental results are discussed together with the confirmatory FE analysis results to assess the in-plane racking performance of the PFGFS. [ABSTRACT FROM AUTHOR]

The aim of this paper is to reconceptualise 'building type' in order to better account for its general role in society and everyday life. The paper merges the concept of building type with actor-network theory and object-oriented philosophy in order to develop the concept of 'territorial sorts' as a way of widening building-type research and making it more useful for investigating how building types are actually produced, not just in terms of the work done by different kinds of authorities, such as architects, engineers, and building regulators, but also in terms of the ongoing practices and power relations of everyday life. [ABSTRACT FROM AUTHOR]

Ground medium can be utilized as a direct energy source to heat and cool buildings. In particular, ground source heat pump systems take advantage of the year-round mild deep earth temperature without a significant reliance on any external energy sources. However, the high installation cost of ground source heat pumps associated with high drilling cost of vertical boreholes often make these systems less cost-effective compared to conventional heating and cooling systems. Thermo-active foundations can be a viable solution to reduce ground source heat pump high installation costs by embedding heat exchangers within building foundation structures. Compared to ground source heat pumps, only limited analyses and research studies have been reported for thermo-active foundations especially for the US climates. In particular, no specific design guidelines have been reported for thermo-active foundations especially for US climates. In this paper, a simplified design approach was developed and applied for specifying geothermal heat pump size and heat exchanger loop length to meet all or part of building heat and cooling thermal loads. The developed guidelines would thus provide a proper design guide for installation of thermo-active foundations for heating and cooling of both US residential and commercial buildings. [ABSTRACT FROM AUTHOR]

The behaviour of composite steel-concrete beams subjected to pure flexure and the presence of flexure and shear is fairly well understood and provisions do exist in international codes of practice for their design, however in most instances the influence of the concrete slab is not included in the strength design of the composite beam in shear. Combined internal actions including the presence of torsion and flexure have also been considered of late. These actions combine to occur in edge beams and curved composite beams and thus are of significant practical interest. Of increasing interest has become the presence of axial force and flexure in composite beams. These internal actions need to be considered in the design of raking beams of stadia, elevated approach spans for bridges and interchanges and in the design of integral abutment bridges and cable stayed bridges. Furthermore, composite beams in floor systems for braced multi-storey buildings are often required to resist axial force, flexure and shear force. This paper considers the effects of the presence of axial force in conventional composite beams. The effects of different forms of axial force and flexure combinations are considered in this paper. An analytical treatment, experiments and design approaches are given in this paper which is useful for structural engineers. Furthermore research in this area is also discussed. This paper will also present the results of an extensive experimental series to study the behaviour of high performance steel sections subjected to transverse impact loads which are able to simulate either a collision or blast. The experimental program has considered both mild structural steel and stainless steel hollow sections both filled and unfilled being tested. The purpose of the tests was to identify the potential advantages of using concrete infill to increase the energy absorption capability of steel hollow sections. [ABSTRACT FROM AUTHOR]

As the title 'Function Follows Performance in Evolutionary Computational Processing' suggests, this paper explores the potentials of employing multiple design and evaluation criteria within one processing model in order to account for a number of performative parameters desired within varied architectural projects. At the core lies the formulation of a methodology that is based upon the idea of human and computational selection in accordance with pre-defined performance criteria that can be adapted to different requirements by the mere change of parameter input in order to reach location specific design solutions. [ABSTRACT FROM AUTHOR]

Buildings are the dominant driver of daily and seasonal electric load cycles, and account for 40 percent of U.S. final energy use. They account for roughly 10 percent of direct U.S. CO2 emissions and roughly 40 percent once indirect emissions from electricity generation are included. This paper explores possible evolution of this sector over the coming century, its potential role climate action and response to climate policies, and the potential benefits advances in building technologies for addressing climate change. The paper presents a set of scenarios based on a detailed, service-based model of the buildings sector that is embedded within a long-term, global, integrated assessment model, MiniCAM. Eight scenarios are created in total, combining sets of assumptions regarding U.S. building service demand growth, two assumptions regarding the improvements in building energy technologies, two assumptions regarding long-term U.S. climate action --- a no-climate-action assumption and an assumption of market-based policies to reduce U.S. emissions consistent with a 450 ppmv global target. Through these eight scenarios, the paper comments on the implications of continued growth in building service demands, the ability of efficiency measures to reduce emissions, the strong link between decarbonization of electricity generation and building sector emissions. [ABSTRACT FROM AUTHOR]

Combined heat and power (CHP) systems can generate electricity locally while they recover heat to satisfy heating loads in buildings, which means they provide efficient energy. On-site generators may reduce both the expected energy costs and cost risk exposure for developers. With volatile energy prices, a deterministic modeling framework will not yield a fair value of CHP systems because flexibility in the operational response to price changes is not taken into account. In this paper, we present a Monte Carlo simulation model that is used to find the CHP value under uncertain future wholesale electricity and natural gas prices. When considering investing in a CHP system on should consider both return and risk. Clearly, both investment return and risk depend on local energy tariffs and energy loads, We highlight an example where CHP is marginally profitable and the investment decision is not straightforward. Interestingly, CHP systems were found particularly attractive with volatile electricity prices because their ability to respond to high prices provides efficient hedges to energy cost risk. Therefore, developers should not be discouraged but rather embrace onsite generation in markets with volatile prices. From the analysis, it can also be concluded that sizing of CHP systems can be related to the energy tariff structure and cost risk preferences as well as to energy loads. [ABSTRACT FROM AUTHOR]

More and more applications exist of base-isolated buildings. So far much attention has been paid to the improvement of design approaches. In this paper, the equation of motion is derived for a torsionally coupled base-isolated structure under the action of seismic ground motion. Based on numerical analyses of the structure, torsional responses and influencing parameters have been investigated and some rules obtained for sites with different soils, in which the superstructure is idealized as a series-rigid floor model, while the isolation system adopts the Bi-linear resilience curve. Applying the method of least squares to the numerical results, three simplified formulae have been produced to approximately calculate the torsional seismic accelerations of base-isolated structures. The results calculated by the practical method proposed in this paper approximate to those obtained by time history analyses. It is shown that the method is of good accuracy in comparative terms and suffices for the needs of engineering designs for base-isolated eccentric structures with rubber bearings under earthquake action. [ABSTRACT FROM AUTHOR]

This paper presents an ethnographic study of how safety is mastered by novices on a building site, in order to highlight the social and cultural character of learning. Adopting a situational focus, the paper explores how knowledge is acquired and transmitted, and how a culture of practice sediments and is perpetuated in the process. The paper takes the community of practices as the privileged locus of learning and transmitting practical knowledge. This study is therefore an attempt to understand in what forms and by means of what mechanisms building-site novices are socialized in the community of practices and how, within this process, the competence relative to safety and danger is learned. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various reports within the issue on topics including use of external ceramics to buildings, wind pressure on high buildings, and building performance.

Increasing renewable-based district heating could contribute significantly to the renewable target achievements of Central and Eastern European Member States with significant shares of district heating in their heat markets. These countries face dual challenges: high competition with other heating sources (including individual heating) and decreasing heat consumption due to buildingrelated energy efficiency improvements in the sector. Our paper is based on a Hungarian case study, attempting to contribute to identifying the most efficient options to achieve these targets in the district heating sector. We apply a district heating model covering all district heating systems in the country and assess the available policy instruments with the potential for increasing renewable energy sources deployment and competitiveness in the sector. The assessment shows that investment grants and operational support are efficient instruments to increase renewable energy sources shares and also improve efficiency in the sector, while end user price and renewable co-generation support in the electricity market lead to non-optimal outcomes. [ABSTRACT FROM AUTHOR]

The concept of ethnicity is a prevailing explanatory device in studies of colonial architecture. This paper argues for decentring ethnicity in buildings research through treating buildings as ‘assemblages’ of both material and social ‘things’. Drawing on a case study from the late 19th-century settler landscape of Manitoba, Canada, we illustrate how settler architecture – conceived of as an ‘assemblage’ – can shed light on the events, processes and material consequences of homesteading in a new land. Through decentring ethnicity as a determining factor in building projects, the role of settler architecture as a material indicator of resistance or assimilation becomes more easily questioned. An archaeological interpretation of buildings as assemblages draws attention towards their materiality and the embodied experiences of building by highlighting the historical and geographical contingencies of the settlement landscape. [ABSTRACT FROM AUTHOR]

The building industry is now evolving in a rapid pace due to the massive need to build and rebuild the cities. While designing the building, the owner appreciates the esthetic aspects, whereas the contractor is more interested in a performance-based approach for its construction. The current study investigates the integration of industrial textiles in buildings. For that, life spawn estimation of textile materials is crucial due to the different existing French regulations that set a minimum durability criterion. The paper presents a methodology for lifetime estimation and an application to two fabrics intended for use as facing materials for buildings. A series of aging tests were carried out and extrapolations were made to reach the research goal. The results of tests that were carried out indicate the feasibility of the textiles’ lifetime estimation methodology used. [ABSTRACT FROM AUTHOR]

This paper presents the design and development of a test protocol for accelerated aging by hydrolysis in basic and acidic media, as well as application of this protocol for testing two fabrics intended for use as facing materials for buildings. The durability indicators were selected in order to quantify and analyse the impact of accelerated aging on fabrics. The experimental results reveal that the two fabrics’ behaviour depends on the medium’s nature. The aging in an acidic medium was hardly noticeable. Conversely, aging in a basic medium resulted in a quick deterioration of the fabrics: after 35 days of aging, the tensile strength of both fabrics was close to zero. Furthermore, the two fabrics behave differently in the basic medium, which is mainly due to their separate structures: the first fabric resistance to nail tear increased during the first day of aging unlike the second fabric. [ABSTRACT FROM AUTHOR]

As an indicator of general indoor air quality in industrial facilities, the concentrations of total volatile organic compounds (TVOC) were determined in the workplaces of 37 industry sectors during the years of 2006–2011. For comparison, the TVOC levels in office-type workplaces were also determined. Based on the results, the TVOC target and guideline values are proposed for industrial workplaces. The geometric mean and median concentrations in the industrial workplaces were 778 and 845 µg/m3, respectively, while the 90th, 25th percentiles were, respectively, 6616 and 270 µg/m3. In the office-type environments, the geometric mean and median concentrations were 55 and 50 µg/m3, and the 90th and 25th percentiles were 230 and 27 µg/m3. Based on the measured TVOC distributions and the target values previously set, we propose a TVOC target value of 300 µg/m3 and guideline value of 3000 µg/m3 for the general indoor air in industrial workplaces. The concentration of 3000 µg/m3 could be achieved with reasonable measures by most industry sectors, but does not guarantee that the inhalation exposure to volatile organic compounds in the occupational environments is free from health concerns or perceived discomfort. Therefore, when reasonably achievable, a TVOC concentration close to or below the target value is recommended. This would make the TVOC levels in industrial facilities similar to those in the non-occupational indoor environments. [ABSTRACT FROM AUTHOR]

Studied in this article is the elastic and inelastic rotational behavior of asymmetric multi-story buildings under unidirectional and bidirectional excitations in relation to the location of the modal center of rigidity. The concept of this point in mono-symmetric uniform buildings has been outlined by the author in earlier papers, and its significance lies on the property that when its location is within a close distance from the mass axis the torsional response is mitigated. At present, a generalized definition of this point is given for buildings with double eccentricity, using (1) the approach of the continuum medium and (2) the stiffness matrix methodology. To determine the location of modal center of rigidity in practical terms, a few modal quantities are required (element frequencies and effective modal masses), which may be easily obtained by commercial engineering software. To verify the aforesaid property of modal center of rigidity under unidirectional and bidirectional excitations, the rotational response of 10-story wall-frame structures is examined under the ground motions of Erzincan 1992 and Kobe 1995. [ABSTRACT FROM AUTHOR]

The long span bridges have been much more flexible and vulnerable to wind induced vibrations due to their continuing increase of span length. To understand the mechanism of wind induced vibrations and achieve better vibration mitigation methods, the complex flow around the bridge decks have been carefully studied using advanced numerical simulations or advanced experimental techniques. In the present paper, the snapshot proper orthogonal decomposition (SSPOD) is used to analyze flow structures obtained from numerical simulations and fluid visualization techniques. The results from numerical simulations based on computational fluid dynamics (CFD) are compared with those from numerical simulations and experiments in the literature and Particle Image Velocimetry (PIV) experiments in the present study. For a demonstration purpose, flow structures around a square cylinder and a twin box bridge deck section were analyzed using the SSPOD. Periodical flow patterns were found in the downstream of the bluff body sections. The revised frozen turbulence hypothesis is used in the present study to analyze the vortex evolution in four phase angles when taking the lift coefficient as a reference signal. Vortex structures are successfully extracted and the vortices are found moving at a constant speed, while the nondimensional frequency of the vortex moving is the same as the Strouhal number. For the twin-box girders, periodical flow pattern changes are found in the downstream of the twin-box girders, as well. [ABSTRACT FROM AUTHOR]

Emerging materials present opportunities to fundamentally shift current expectations of dynamic building envelope functionality towards systems that can respond to occupant needs while meeting the energy demands of buildings. In order to assess the environmental, social, and architectural opportunities that are increasing with responsive building envelopes, new tools are needed to simulate their multi-performance capabilities. This paper describes a computational design framework to support human interaction with environmentally-responsive electroactive dynamic daylighting systems. The objective is to develop algorithms for variable solar control and visible transmittance that simultaneously address occupant preferences for visual effects and interaction. Results demonstrate that energy performance and user satisfaction are not mutually exclusive and can be co-optimized. The effectiveness and limitations of the computational framework in assessing strategies to balance environmental performance and human interaction are discussed. Conclusions present areas of ongoing work that integrate multi-user interactions and immersive visualization techniques with multiscalar energy modeling tools. [ABSTRACT FROM AUTHOR]

In this paper an efficient method is presented to reduce the computational complexity of analysis of structures in the process of size and geometry optimization by genetic algorithms. Applying the present method, results in simultaneously swift analysis and optimal design of structures. In this method, using matrix computations, fast solution of the structures is obtained. The analysis of the structures in the optimal design via GA, includes the solution of the relationship F = KΔ in each generation of the genetic algorithm. Inverting the stiffness matrix in each generation and for each population for finding the displacements and internal forces is very time-consuming and costly. Here, using a closed-form matrix solution, compatible with the features of genetic algorithms, the amount of computations is decreased. The optimal analysis of optimal size is performed using a modified solution for structures with changed members and the optimal analysis of optimal geometry is done via a modified solution for structures with changed supports and nodes. To make the method more efficient, proper orderings are presented using the concept of Fiedler vector and partitioning matrices. [ABSTRACT FROM AUTHOR]

This paper introduces an equation developed based on the strut-and-tie analogy to predict the shear strength of reinforced concrete columns with low transverse reinforcement ratios. The validity and applicability of the proposed equation are evaluated by comparison with available experimental data. The proposed equation includes the contributions from concrete and transverse reinforcement through the truss action, and axial load through the strut action. A reinforced concrete column with a low transverse reinforcement ratio, commonly found in existing structures in Singapore and other parts of the world was tested to validate the assumptions made during the development of the proposed equation. The column specimen was tested to failure under the combination of a constant axial load of 0.30 f'cAg and quasi-static cyclic loadings to simulate earthquake actions. The analytical results revealed that the proposed equation is capable of predicting the shear strength of reinforced concrete columns with low transverse reinforcement ratios subjected to reversed cyclic loadings to a satisfactory level of accuracy [ABSTRACT FROM AUTHOR]

The present paper analyses the design procedure and its impact on seismic safety of the structures. For this, a representative reinforced concrete frame building (WDS) is designed and the results are compared with similar buildings detailed with: i) Current Construction Practices (CCP); ii) the Nepal Building Code (NBC) and iii) the Modified Nepal Building Code (NBC+) recommendations. The seismic performance evaluation is done with global strength, inter-storey drift and displacement of the structures. Likewise, the sensitivity of the structural and geometrical parameters of the RC frame building is studied through nonlinear analysis. The study parameters considered for parametric analysis are column size, beam size, inter-storey height, bay length, bay width, and compressive strength of concrete. The results show that the influence on the structural behaviour, particularly by variation in column size and inter-storey height. Additionally, the influence of the seismic zone factor on reinforcement demand of the structure is studied. The result shows that structures designed for high to medium seismic hazard demands double the reinforcement in beams compared to structures in low seismic zone. [ABSTRACT FROM AUTHOR]

This paper presents an improved firefly algorithm (FA) for fast optimization of truss structures with discrete variables. The enhanced accelerated firefly algorithm (AFA) is a simple, but very effective modification of FA. In order to investigate the performance and robustness of the proposed algorithm, some benchmark (structural optimization) problems are solved and the results are compared with FA and other algorithms. The results show that in some test cases, AFA not only finds lighter structures compared to other algorithms, but also converges faster. In the rest test cases, the optimal solutions are found with very less computational effort. The study also shows that the proposed AFA remarkably improves stability of the firefly algorithm in discrete design of truss structures. [ABSTRACT FROM AUTHOR]

The article offers information on the Central European Conference on Building Physics (CEC-BP) to be held in Cracow, Poland on September 13-15, 2010.

Highlights the 4th international conference on energy on buildings held in Lithuania on September 21-22, 2000. Organizers of the conference; Aim of the meeting; Topics discussed; Speakers.

Even though the measures to minimize the stack effect in high-rise buildings were taken that include a revolving door on the lobby floor, additional barriers to the passage of air in the lower part of the building, and air-tightness reinforcement for elevator doors, the stack effect is still present during cold season in Korea. However, it is difficult to fully apply the measures for stack effect under occupied condition in high-rise buildings. In this study, as an advanced method to lower the stack effect in high-rise buildings under occupied condition, mechanical ventilation in elevator shaft space, which cools the shaft space with outdoor air and reduces the temperature or pressure differences between indoor air in shaft and outdoor air, was proposed. In this paper, the application details and performance analyses of the installed shaft cooling system in a completed building in Korea were described. Also, as a measure to improve the performance of the applied system, concentrated cooling in the lower part of the elevator shaft where there is a main air flow passage was proposed. As a result, cooling effect of mechanical ventilation system in elevator shaft was improved and the extent of stack effect in winter was decreased effectively. [ABSTRACT FROM AUTHOR]

Due to the fact that some structural external excitations such as earthquakes and wind forces can not be accurately measured under actual operating conditions, it is necessary to investigate algorithms for structural identification under unknown earthquakes. In this paper, an algorithm based on the extended Kalman estimator approach is proposed for the identification of structural parameters and unknown excitation of tall shear-type buildings with only partial measurements of structural absolute acceleration responses. The equation of motion of a tall shear building under ground motion is established in the absolute co-ordinate system, in which the ground-motion input is applied to the 1st floor of the building as an unknown excitation. Based on substructure approach, the tall building is decomposed into substructures. For each substructure above the 1st floor, substructural relative responses and parameters are identified by extended Kalman estimator. For the substructure containing the 1st floor, it is proposed that substructural extended state vector is firstly identified by the extended Kalman estimator and the unknown excitation is subsequently estimated by least-squares estimation. Then, the 1st story stiffness is estimated based on structural eigenvalue equation and the expansion of the determinate of the structural eigen-matrix. The unknown ground motion is identified by the Newmark-β method. A numerical simulation example demonstrates the efficiency of the proposed algorithm. [ABSTRACT FROM AUTHOR]

In this paper an efficient method is presented for the analysis of those structures which can be formed by addition some members to regular structures. This method is also applicable when some members are reduced from regular structures. If a model is the union of a regular structure and some additional members, then these members are separated from the structure, and their effect is introduced through equilibrium matrix and added to that of the regular structure. For models which lack some members, pairs of hypothetical elements with positive and negative modulus of elasticity are added, and the members with negative modulus are separated from the structure resulting in a regular structure. [ABSTRACT FROM AUTHOR]

To obtain satisfactory sound insulation is a challenging task when designing lightweight buildings. Poor performance at low frequencies as well as severe flanking transmission has traditionally often been more pronounced compared to heavier constructions. In the present casestudy based paper, various aspects of using elastic layers to improve sound insulation in lightweight buildings are considered.The effect on impact and airborne sound insulation by using two different kinds of vibration insulators between floor plans was examined together with the effect of using glues of various degree of elasticity in the construction. In situ measurements were performed inside a four-storey wooden frame based residential building and statistically significant variations in sound insulation were found.The efficiency of the two vibration insulators was further evaluated by vibration reduction measurements over the junctions. The difference in vibration reduction was found to be nearly constant in the frequency range 50-1000 Hz while the improvement of impact sound insulation increased by frequency.Along term test of elastic glues was also conducted, during three years, for stability over time. The best glues preserved a significantly higher damping ratio over time compared to the main part of the glues. [ABSTRACT FROM AUTHOR]

For the China National Aquatics Center, this paper reports an investigation into the effects of temperature change on modal parameters. Both analytical and field monitoring approaches were involved. Temperature-induced variations of structural member modulus of elasticity, internal forces and changes to boundary conditions were regarded as the essential factors influencing modal parameters. The contribution of these three effects on modal parameters for both uniform and non-uniform temperature distributions over the structure was investigated. It is concluded that temperature-induced internal forces affect the modal parameter values to greater extent than temperature-induced modulus of elasticity. The relationships between temperature and variation of modal parameters are different in the case of uniform and non-uniform temperature distributions. The analytical results were validated by using the acceleration and temperature measurements supplied by the China National Aquatics Center field monitoring system. [ABSTRACT FROM AUTHOR]

The article presents abstracts on planning literature which include approaches to empirical work in regional economics, understanding the barriers to social adaptation, and management of large city regions.

Established during the Italian Renaissance, the term 'design' derives from the Italian disegno, meaning 'drawing', suggesting both the drawing of a line on paper and the drawing forth of an idea. Consequently, the drawing is familiarly understood as the prototype for building. However, in this text, I suggest that the term 'prototype' is applicable to all stages of the architectural process, from drawing to building to using, as well as evolving conceptions of the architect. [ABSTRACT FROM AUTHOR]

A light-pipe system can introduce daylight into the deeper building interiors, thus potentially displacing the requirement for electrical lighting. For the light-pipe system to be widely used in Korea, it is important to quantify its daylighting performance with due consideration regarding the effects imposed by the local climate conditions. This paper reports the development of a model to predict the daylighting performance of a light-pipe system used in Korea. This model study was based on the monitoring data obtained from a windowless space in which the light-pipe system was installed. The model can predict indoor illuminance distributions and daylight penetration factors as a function of outdoor illuminance, solar altitude and the amount of cloud present. Comparisons were made between the predicted and the monitored data obtained from the study; and also between predictions given by the developed model and other existing predictive models. The comparisons have provided validation of the newly developed model and that the predicted results were robust and reliable. [ABSTRACT FROM AUTHOR]

The use of natural lighting has the potential for improving both the energy efficiency and indoor environmental quality in buildings. A light-pipe system can bring natural light to spaces that would otherwise not be able to benefit from the advantages of daylight penetration. This paper presents the monitoring results of a light-pipe system that was installed in a windowless space of a building located in Korea. Indoor illuminance distributions and concurrent outdoor illuminance were monitored at a 1 s interval over a period from April 2009 to May 2009. The results demonstrated the effects caused by the amount of clouds, solar altitudes and external total illuminances; on both the daylighting performance of the light-pipe system and the indoor illuminance distributions of the space. The findings of this study indicated that the light-pipe system could be an effective tool particularly for introducing daylight indoors, even under overcast sky conditions in Korea. [ABSTRACT FROM AUTHOR]

New building designs following the New Zealand Building Code Approved Documents complete a 'risk matrix' of climate and building design factors with associated 'risk scores' to guide the selection of wall cladding and cavity design. The risk matrix is briefly described in this paper, along with cavity ventilation results measured with a continuous emission carbon dioxide tracer method. Ventilation rates in a selection of wall cavities are compared with ventilation rates calculated from wind pressures and vent opening sizes. Fan pressurization methods are used to measure the effective leakage areas of infiltration paths because these contribute significantly to ventilation in some cavity types. Acceptable agreement between calculated and measured day average ventilation rates has been achieved in a range of water-managed cavities from drainage planes to drained and ventilated brick veneer cavities with results spanning three orders of magnitude. [ABSTRACT FROM AUTHOR]

This paper describes a novel class of meta-materials that exhibit significantly greater transmission loss than conventional sound insulation systems of similar size and weight over selected frequency bands. This is achieved by the action of small resonator elements distributed throughout the wall at spacings much smaller than the wavelength of structural vibrations in the base wall material. The research reported here is at an early stage. Experiments are described which demonstrate enhanced transmission loss in small proof-of-concept samples and a simple theoretical model is presented. [ABSTRACT FROM AUTHOR]

This paper proposes a pragmatic methodology to manage the air quality of an air conditioned building as well as optimizing energy consumption during venting. Radon-222 (Rn-222) is used as a tracer to quantify the specific production rates and resultant losses of pollutants for which the information is important in indoor air quality management. A term, indoor pollutant inventory, is introduced for easy handling of various indoor pollutants. The specific production rate (Φj) of pollutant-j is the production rate of a pollutant normalized by the control volume of sampled room. The resultant loss (Lj)RL of pollutant-j is defined as the sum of its natural decay (λj), reaction loss (Rj), and ventilation loss (q/v). Rn-222 and total volatile organic compounds are used to verify the methodology. In the verification tests, the air conditioned system of an office was scheduled to shut down overnight and return to supply mode in the next morning. The build-up and decay of the pollutants were measured and used to quantify (Φj) and (Lj)RL. The values of (Φj) and (Lj)RL. obtained from the pollutants at two different modes mutually agreed with each other. The mean specific production rates of Rn-222 and TVOC were 20.7 Bq·m-3·h-1 and 2.0mg·m-3·h-1 respectively, while the lump sum of chemical and natural losses of these pollutants were 0.0076 h-1 and 0.0226 h-1, respectively. Concentrations of the pollutants at various air change rates were also simulated in the study. [ABSTRACT FROM AUTHOR]

This section presents abstracts of papers on city planning published from 2007 to 2008, including "Streets, Sounds and Identity in Inter-war Harlem," by Clare Corbould, "(Re)making the Other, Heterosexualising Everyday Space," by Kath Browne, and "Rankings and Reactivity: How Public Measures Recreate Social Worlds," by Wendy Nelson Espeland and Michael Sauder.