The daylighting dashboard – A simulation-based design analysis for daylit spaces

This paper presents a vision of how state-of-the-art computer-based analysis techniques can be effectively used during the design of daylit spaces. Following a review of recent advances in dynamic daylight computation capabilities, climate-based daylighting metrics, occupant behavior and glare analysis, a fully integrated design analysis method is introduced that simultaneously considers annual daylight availability, visual comfort and energy use: Annual daylight glare probability profiles are combined with an occupant behavior model in order to determine annual shading profiles and visual comfort conditions throughout a space. The shading profiles are then used to calculate daylight autonomy plots, energy loads, operational energy costs and green house gas emissions. The paper then shows how simulation results for a sidelit space can be visually presented to simulation non-experts using the concept of a daylighting dashboard. The paper ends with a discussion of how the daylighting dashboard could be practically implemented using technologies that are available today.     

Elasto–plastic analysis of steel plane frames using Homotopy Perturbation Method

In this research a new nonlinear method is developed based on Homotopy Perturbation Method (HPM) and is applied to elasto-plastic analysis of steel plane frames. The Homotopy algorithm can be considered as an advancement into classical methods of numerical computation such as Newton–Raphson method. In perturbation methods, perturbation quantities are used to transfer a nonlinear problem into a number of manageable linear sub-problems. Then an approximate solution is reached by summing up the results of first several sub-problems. The HPM developed here is applied to plane frames in which elastic–perfectly plastic behavior is assumed for structural material while conventional plastic hinges of zero length are used to model plasticity effect. Numerical examples are presented in this paper to show the accuracy and effectiveness of the proposed approach. Results obtained showed that when developed HPM is used for elasto-plastic analysis of structures, using various yield criteria for steel elements, less iteration is required to reach solution, and convergence is achieved very fast compared with conventional Newton–Raphson method.     

Combustion analysis of the diesel–biogas dual fuel direct injection diesel engine – the gas diesel engine

In this investigation, biogas (BG) was used as an alternative fuel in a single-cylinder, four-stroke, air-cooled, direct injection (DI) diesel engine that was operated on a dual fuel mode. Biogas was produced from a non-edible seed de-oiled cake-pongamia pinnata (Karanja), which was collected from the biodiesel industries. The BG was inducted along with the air in suction of the engine at four different flow rates varying from 0.3?kg/h to 1.2?kg/h in steps of 0.3?kg/h. The investigation results revealed that BG inducted at a flow rate of 0.9?kg/h gives better combustion characteristics of engine behaviour than those of other flows throughout the engine operation. The ignition delay (ID) and combustion duration of the engine run by dual fuel operation at a BG flow rate of 0.9?kg/h were found to be longer by about 2 °CA and 2.9 °CA, respectively, in comparison with diesel at full load. The cylinder peak pressure was found to be overall higher by about 11?bar than that of diesel at full load.     

The impact of biophilic design in Maggie’s Centres: A meta-synthesis analysis

This paper presents a meta-synthesis conducted to identify, compare and synthesize published qualitative data related to the Maggie's Centres, as a paradigmatic architectural example in the provision of non-institutional cancer support. These centres are internationally renowned for their unique architecture, where the careful design of indoors and outdoors spaces plays a critical role in their agenda for supporting care. Previous research has thoroughly analysed this approach to therapeutic environments, not only confirming the importance of designed space as originally conceived in Maggie's philosophy but also identifying precise supporting effects associated with specific elements within their design. This paper aims to provide a new reading of Maggie's contribution to cancer support by offering an examination of all these data through the lens of biophilia, which clarifies the impact of design decisions connected to nature on cancer patients' lives. The analytic process included a systematic search strategy, extraction and classification of salient concepts using an open-coding approach, and lastly an interpretive evaluation. The systematically selected data helped to identify and rank the biophilic design parameters that appear the most critical for promoting and supporting human health and wellbeing in non-clinical therapeutic environments, from the user's perspective. It also provided a compilation of distinctive design interventions related to biophilic parameters, which provides benchmark information for future research and design guidance in these environments.     

Practical nonlinear analysis of steel–concrete composite frames using fiber–hinge method

A fiber–hinge beam–column element considering geometric and material nonlinearities is proposed for modeling steel–concrete composite structures. The second-order effects are taken into account in deriving the formulation of the element by the use of the stability functions. To simulate the inelastic behavior based on the concentrated plasticity approximation, the proposed element is divided into two end fiber–hinge segments and an interior elastic segment. The static condensation method is applied so that the element comprising of three segments is treated as one general element with twelve degrees of freedom. The mid-length cross-section of the end fiber segment is divided into many fibers of which the uniaxial material stress–strain relationship is monitored during analysis process. The proposed procedure is verified for accuracy and efficiency through comparisons to the results obtained by the ABAQUS structural analysis program and established results available from the literature and tests through a variety of numerical examples. The proposed procedure proves to be a reliable and efficient tool for daily use in engineering design of steel and steel–concrete composite structures.     

‘But that is a systems solution to me’ – negotiations in IT design

In this paper we argue that it is not self-evident how ‘requirements’ are defined, but that ‘requirements’ are enacted differently by differently situated actors, and that this has consequences in design practices. The purpose of the paper is to explore the consequences of prototyping practices in a local IT design project. The empirical material was gathered through the use of ethnographic methods, and analysed diffractively. Graphical user interface prototypes were tools for formulating business requirements in a business process analysis. Through a reading of a discussion which took place in a work meeting about the prototypes, we discuss how business requirements were enacted. This is discussed in relation to divergent and convergent approaches in IT design. One consequence was a risk that the prototyping process moved too fast to solutions, and another was the risk that the business process analysis method reproduced the dominant story of women's absence in IT design.     

Seismic performance of irregular bridges – comparison of different nonlinear static procedures

The adequate seismic performance of transportation infrastructures is important for the functioning of the economy and society. This paper focuses on the seismic assessment and analysis of one of the most important components of these infrastructures, the bridges. In this field, nonlinear static procedures (NSPs) have gained significant attention, resulting in different proposals to improve the accuracy of the procedures while keeping their simplicity. The main goal of this study is focused on the evaluation of the applicability of NSPs for irregular reinforced concrete viaducts. A comparative approach is pursued by resorting to (1) the analyses of the performance of three well-known NSPs (N2 method, modal pushover analysis and adaptive capacity spectrum method) and (2) the extension of the scope of previous studies in this field to a more recent method, the extended N2. As such, a set of bridges with different levels of irregularity, configurations and lengths is investigated. The accuracy of different NSPs is evaluated by comparing the results of NSPs with the ones obtained by means of nonlinear dynamic analyses. The comparison of results confirms the acceptable performance of the multi-modal NSPs and highlights the effectiveness of extended N2 method with respect to its simplicity.     

Assessing the implementation of BIM – an information systems approach

Much attention has been paid to measuring the perceived benefits of Building Information Modelling (BIM). Yet despite an increase its adoption throughout the construction industry, important links between implementation, support and benefits are yet to be explored. We examine the constitutive elements of the BIM implementation process of two case studies implementing and using BIM: the first is a large urban regeneration project, and the second is a healthcare project. A well-recognised model of system success is mobilized from the field of information systems (ISs) to reveal that irrespective of project size and type, BIM benefits are confined to technically discrete productivity and efficiency gains when there is limited focus on the organizational aspects of BIM adoption. This paper focuses on the disconnections between organizational and project level BIM implementation using the DeLone and McLean Model as an analytical framework to systematically examine the benefits of BIM to each project in relation to the implementation approach employed. This study highlights the significance of these interdependencies and argues for a more comprehensive approach to BIM benefits capture that recognises this to usefully inform implementation strategy development.     

The feasibility of new design of hybrid photovoltaic-thermal system – a theoretical approach

Hybrid photovoltaic thermal (PVT) collectors have been evaluated according to the physical features of commercial photovoltaic (PV) cells; therefore, their commercial application is limited. The Tedlar collector has good electrical insulating properties, resulting in reduction in electrical efficiency. A researcher found that a glazed PVT system without Tedlar was the best among others, showing a significant increase in the overall efficiency. Inspired by this finding, we thought to study, for the first time, the feasibility of a new PVT that has been built by modifying a commercial PV panel and retrofitting it with the integration of two tubes in glass above the PV cell pasted on a thin metal ribbon before PV encapsulation. A heat transfer modelling/simulation in 3D was performed using COMSOL Multiphysics software.

The results show that under the no-cooling situation, the PV cell temperature reaches 74.87°C and the electrical power dropped significantly to 0.113 for electrical efficiency of 0.15 at the reference conditions. The water flow velocity is determined so that the cell can be effectively cooled. The cell temperature variation reaches to 45.9°C for a flow velocity of 0.5m/s, an irradiation of 1000W/m² and ambient temperature equal to 20.15°C.     

Optimum mix design of enhanced permeable concrete – An experimental investigation

Permeable pavement, due to its high porosity and permeability, is considered as an alternative to traditional impervious hard pavements for controlling stormwater in an economical and friendly environmental way. Permeable concrete normally made of single-sized aggregate bound together by Portland cement, using restrictedly as a pavement material, because of its insufficient structural strength. Aimed at developing a new type of permeable concrete with enhanced structural strength, various mix designs were attempted and their effects on the compressive strength and permeability of permeable concrete were investigated in this research. The optimum aggregate and mix components design were consequently recommended for enhanced permeable concrete.     

Embedding built environments in social–ecological systems: resilience-based design principles

Globalization, the process by which local settlements and ecosystems are becoming linked in a global network, presents policy scientists and planners with difficult design challenges. Coping with either natural or built environments in isolation is extremely challenging in its own right (e.g. built environments at different scales: a single building, a collection of buildings, a neighbourhood or a city are in themselves very complex). In the Anthropocene era, where human activities shape the planetary system in which built and natural environments are becoming more tightly linked across scales, these complex systems need to be considered as elements in a global network, i.e. as a coupled social–ecological system (SES) at the global scale. In the context of this spiralling complexity, multi-scale and multilevel processes become more important and design/management problems become extraordinarily difficult. Preliminary ideas are explored for how research on this multilevel design problem might proceed. Specifically, based on combining insights from a collection of theories and models based on resilience and robustness concepts, the basic elements of a new approach are presented that recognizes the importance of self-organizing processes at multiple scales and emphasizes the use of feedbacks to link these processes across scales.     

Seismic design of inelastic structures using equivalent linear system parameters: part 1 – derivation and comparison

This article, which is the first of a two-part article, presents equations for computing equivalent linear system (ELS) parameters using a two-dimensional minimisation technique for estimating inelastic seismic demand of structures from elastic response spectra. Using two hysteretic models, the effects of initial damping, post-yield stiffness and degrading behaviour on the ELS parameters are investigated. The maximum inelastic response of structures modelled as single degree-of-freedom systems computed using the proposed method are compared with five other approximate methods as well as with results obtained using inelastic time-history analysis. It is observed that the proposed approach gives good results for structures that experience ductile behaviour with natural periods in the 0.3- to 3-s range.     

Seismic design of inelastic structures using equivalent linear system parameters: part 2 – application and verification

In this second part of the two-part article, the incorporation of a set of equivalent linear system parameters derived in the preceding article in a direct displacement-based design (DDBD) method is presented. By using the proposed design procedures for reinforced concrete and steel, 16 structures modelled as single degree-of-freedom systems are designed. Their responses are then compared with those obtained from a dynamic inelastic time-history analysis. The results show that the use of the proposed equations to calculate ζ_eq and T _eq and the incorporation of the proposed DDBD procedures to proportion structures will produce reasonably good results with relatively simple computation effort.     

Large scale dynamic testing of rock support at Kiirunavaara – Improved test design

Based on the test results and preliminary numerical analysis of four large scale dynamic testing of rock support (Tests 1, 2, 4, and 5), a modified test (Test 6) was designed at LKAB Kiirunavaara underground mine. The aim of the modified design was to avoid the unexpected damage of burden as was observed in earlier tests, and to modify the dynamic loading leading to increase the depth of fractured zone and if possible pushing the support system beyond its limit. In this test, ground motion measurements were conducted using accelerometers, fracture investigations were made using an inspection borehole camera, and ground motion imaging and laser scanning were performed before and after blast. In Test 6, the columns of explosive were located in the middle of a pillar between two cross-cuts one supported by a rock support for seismic conditions, and the other supported by only plain shotcrete. Results indicated that a larger fractured zone compare to earlier tests was developed behind the support system while the installed support system was still functional. In cross-cut without support system, the ejection of blocks of rock from the test wall was observed. Evidence from two cross-cuts indicated a reduction of radial cracks that provide access for the gas expansion. Furthermore, the performance of the rock support was investigated by comparing with the results from the unsupported cross-cut. The results indicated that the installed support system, designed for dynamic conditions, performed well under the loading conditions which can cause ejection.     

Claiming participation – a comparative analysis of DIY urbanism in Denmark

The article discuss the conflicts, potentials and possible alliances of do-it-yourself (DIY) urbanism when it takes the form of spontaneous place appropriations, when it is performed as participatory urban design and when it is integrated strategically in planning. DIY urbanism and experimentation with participation are currently strong influential factors in Danish planning. The article explores the use of participatory DIY urban design in two cases: the relocation of beer drinkers in Enghave Square and the Carlsberg City development in Copenhagen, Denmark. Carlsberg City is the most thorough Danish example of how DIY urban design is employed as an investment and planning tool. It discusses the implications of DIY urbanism in terms of how it can be understood in the context of the struggles over ‘the right to the city’, how it applies different activist tactics for the appropriation of space, and how it is integrated in planning and the development logic.     

Vibration based stiffness reconstruction of beams and frames by observing their rotations under harmonic excitations — Numerical analysis

Recent progress in data acquisition technology makes it possible to measure not only translational but also angular vibrations of beam and frame structures. This raises a question whether these new methods can effectively be applied in damage structural detection and localization. For this purpose a damage detection method aiming at reconstructing the stiffness distributions of a structure from its vibration measurements is tested when rotational degrees of freedom are added to the dynamic model of the structure. The stiffness reconstruction is formulated as a minimization problem in terms of harmonic vibrations of the structure and its finite element model. Two examples of a beam and frame structure are analyzed in detail. To better test the damage detection algorithm, measuring noise with various levels has been added to the analyzed signal. The results of the numerical analyses show that the application of genetic algorithms and a Levenberg–Marquadt local search appeared to be even more effective in damage detection when the angular amplitudes of harmonic vibrations are acquired. This creates good prospects for the future applications of angular accelerometers in structural health monitoring of civil engineering structures.     

Temperature of a photovoltaic module under the influence of different environmental conditions – experimental investigation

The climate changes affect photovoltaic (PV) module temperature significantly. The module temperature is one of the most important factors that influence the PV module efficiency and a deep analysis of PV module temperature will aid in better understanding of the environmental influences on the PV module performance. The module temperature depends on many parameters such as solar radiation, ambient temperature, air humidity, speed and direction of the wind, PV module orientation, dust and sand deposition on PV module, and PV module materials. An experimental research was conducted to investigate the effect of these factors on the PV module temperature in the Renewable Energy Laboratory of the Graduate University of Advanced Technology in Iran. The results of this study highlighted that the deposited dust over the PV module surface increases the module temperature and this consequently decreases the PV module power. It was also revealed that a combination of the temperature increase and the incident solar radiation decrease due to the dust deposition over the PV module enhances significantly the module power reduction.     

Rationalisation and reliability improvement of fire-fighting systems – the Novi Sad case study

Water supply systems are commonly used to supply fire-fighting water in most EU countries. To provide fast access to water, the standard practice is to install a huge number of hydrants along the entire water supply network. Pipe diameters and working pressures in the network are designed for a combination of the maximum hourly water demand and fire-fighting needs. However, in poorly managed water supply systems most of the hydrants are out of order. Although hundreds of hydrants exist in the network, the reality is that fire water tankers are usually refilled at just a few locations that are equipped with reliable hydrants maintained by the fire brigades. This paper presents a somewhat different approach for the provision of fire-fighting water. The approach discussed in the paper is based on the concept being introduced in the city of Novi Sad, Serbia, by cooperative efforts of the municipal Water Supply and Sewerage Company and the fire-fighting service. In addition to presenting the experience gained in the case study, some generic conclusions are drawn. As an alternative to having a number of unreliable and small hydrants distributed throughout the network, the new concept proposes the construction of several strategically positioned filling stations, with high-flow-rate pillar hydrants and good access roads for the manoeuvering of fire water tankers. If properly designed and distributed around the city, such filling stations would increase the reliability of fire-fighting operations. The filling stations' design methodology presented in this paper is composed of a fire-risk spatial assessment, a hydraulic check of water supply network operations and a worst-case traffic load analysis. By employing the proposed methodology, not only can the reliability of fire-fighting operations be increased, but if accepted and implemented the methodology can lead to leakage reduction and improvements in water quality and the system's energy efficiency. In the test case of Novi Sad, a large number of hydrants were replaced by 14 filling stations that have been designed and constructed. A hydraulic model of the water supply network was calibrated using pressure-drop tests and flow capacity measurements of the existing hydrants. The model was used to examine the performance of the designed filling stations during their parallel operation. The paper presents the results of the test application and recommendations for the possible implementation of the concept.     

Seismic analysis and strengthening design of a masonry monument by a rigid body spring model: The “Maniace Castle” of Syracuse

The seismic analysis of a large monument subjected to strong earthquakes is the object of the present paper. As a case study, the response of the “Maniace Castle” of Syracuse has been investigated by a multi-level approach which adopts traditional finite element modelling as well as a specific mechanistic computational model for the final non-linear seismic analyses. At first, the linear behaviour of the monument was studied by means of two 3D FE models in order to understand the global response of the building, its points of weakness, and the kinematics of the corresponding collapse mechanisms. Then, these results were used to calibrate a mechanistic 2D plane rigid body and spring model, RBSM, specifically formulated with the aim of approximating the macroscopic behaviour of masonry walls with reduced degrees of freedom, and taking into account the influence of the masonry texture and energy dissipation capacity of the material. Given the uncertainties and the variability of the material characteristics, an extensive parametric non-linear static analysis and the dynamic analyses, with artificial and natural accelerograms, were made in accord with the EC8 seismic code, and compared together. These results were then used to formulate and verify a simple proposal for the restoration design.