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Digitization and automation are essential tools to increase productivity and close significant added-value deficits in the building industry. Additive manufacturing (AM) is a process that promises ...

At the same time of economic development, the increasing scarcity of energy has had a great impact on people's development. People's production and life demand for electricity is also increasing rapidly, and solar power technology has received more and more attention. As a new energy source, solar energy has the advantages of environmental protection and sustainability, and it has no regional restrictions, can be used on-site, and designed to scale. Solar power generation is an important way to use solar energy. As the main component of the grid-connected power generation system, solar grid-connected inverters complete the tracking problem of the maximum power point in the photovoltaic array and transmit electrical energy to the grid through a set of control algorithms. The electrical energy is transmitted to the grid through the inverter, consistent with solar energy. In order to solve the problems of low integration, low energy efficiency, low reliability, high power consumption and lack of effective monitoring measures for solar energy devices. This article starts with the design of the solar cell integrated system, and through detailed analysis of the solar production system and building integrated planning, establishes the shadow radiant energy model of the solar cell system building electrical and solar cell system based on the Internet of Things, and designs an object-based Networked comprehensive auxiliary platform. The use of the Internet of Things and ZigBee wireless sensor network to study distributed solar energy devices and realize the joint design of solar energy devices and buildings is of great significance to the development of photovoltaic construction industry.

According to the few researches on Nearly zero energy residential buildings (NZERB) in hot-summer and cold-winter zone, although it could reduce the cooling load of buildings due to its high thermal insulation and air tightness, it still needed for certain cooling in summer. This paper studied indoor environment of NZERB under three kinds of air-conditioners (split-type air-conditioner, multi-line air-conditioner and ceiling radiant air-conditioner). Firstly, a simulation model of NZERB was established based on Nanjing, a typical city in hot-summer and cold-winter zone. Secondly, variation of indoor air temperature and building load characteristics with outdoor air temperature were studied. Thirdly, indoor environment and energy consumption under three selected conventional air-conditioners in summer were simulated. Finally, the discussion was given, and an air-conditioner combining with convective and radiant cooling were proposed. The results indicated that the air-conditioner needed to be turned on in NZERB in hot-summer and cold-winter zone due to the room air temperature in off-air condition ranged from 32 °C to 36 °C, which was higher than designed indoor environment temperature in summer, but the indoor environment of NZERB under three selected conventional air-conditioners could not meet the requirements of energy saving and comfort at the same time, and a proposed convective-radiant air-conditioner could be fast, stable, and energy saving. The findings can provide a reference for conducting active technology in NZERB.

The formwork system (FWS) is one of the key components in reinforced concrete (RC) construction. Therefore, selection of the most appropriate FWS plays a critical role in the project success. Because selection of the FWS is affected by several compromising and conflicting criteria, since the early 1990s, numerous studies have been carried out to identify the FWS selection criteria and (or) have employed various multicriterion decision-making (MCDM) methods. However, there is no research to date that has conducted a critical review of the previous studies addressing the FWS selection criteria in construction projects. This study aims to fill this knowledge gap. For this purpose, a critical review of the relevant literature was carried out using an integrative approach, and the findings were validated through face-to-face interviews with professionals specialized in formwork engineering. The findings of this study should provide practitioners with a useful guide that can assist them in selecting the most appropriate FWS.

The triple-junction solar cell is designed to exploit a wide range of the solar spectrum photons. These triple-layers consisting of GaInP/GaInAs/Ge, it is monolithically stacked, leading to high conversion efficiency. To describe and understand it's operating behaviour, this paper presents a performance analysis of a triple-junction solar cell, based on estimation modelling. A model was developed to determine the performance characteristic of the solar cell. Hence, the J-V curve is characterising the performance of solar cells, which used to optimise and improve the design of the cells. It has been discussed the effects of thermal load related to cell temperature increases on the cell's operating performance parameters. Cell temperature increases from 25 to 125 °C have resulted variances, which causes a significant decrease in efficiency to approximately −17%, open circuit voltage by −15% and fill factor by −4.5%. On the other hand, the current density slightly increased by +5.5%. Finally, ought to consider the thermal management while designing and developing solar CPV technology; therefore, it's significant to improve cell efficiency and to maintain cell integrity from thermal damage.

Renewable energy has become an important choice to solve the energy crisis and environmental problems. A sustainable development needs policies and strategies policies, which can improve energy efficiency and reduce greenhouse gas emissions. By collecting the research results released by relevant statistical departments and authoritative institutions, this paper summarizes the international energy development situation, systematically combs the energy development situation of the European Union, United States, Australia, India, Brazil. The development trend of wind, solar, biomass, geothermal, ocean, and hydrogen energy have been analyzed. In addition, this paper proposes that China should draw up its own development path of renewable energy from international development experience, and actively explore renewable energy policies and strategies adapted to different stages of development.

Polystyrene (PS) is rich in plastic materials, but it produces a large amount of waste every year, causing a huge burden on the environment. Although PS plastic is the source of a common "white pollution" in daily life, it still has a high utilization value. At the same time, the flammability of PS material determines that it cannot be applicated in places where fire accidents occur frequently. As a result, its application has been greatly limited. In order to realize the efficient utilization of waste PS and broaden its scope of application, PS was modified by hyper-crosslinking in order to improve its fire-retardant performance. In this method, the PS solution with high purity was obtained by dissolving waste PS foam with 1,2-dichloroethane (DCE), and then the hyper-crosslinked polymer with high specific surface area was prepared by adding cross-linking agent formaldehyde dimethyl acetal (FDA) and a Lewis-acid catalyst ferric chloride (FeCl3). Further studies showed that the effects of the amount of cross-linking agent FDA, catalyst FeCl3 and PS on the reaction products were different. In addition, compared the as-prepared fire-retardant materials with PS foam from the aspects of flame retardancy and thermal insulation, it can be concluded that the fire-retardant performance of the materials prepared by this method has been significantly enhanced. And it is proved that this method is feasible towards the preparation of a large number of fire-retardant composite materials by using a scale-up experiment.

An appropriate microenvironment for preserving cultural relics is essential, and the air-water direct contact technology is utilized to create the microenvironment recently. The influence of a deflector in a tank was numerically investigated based on uniform design method to improve the heat and mass transfer and pressure drop performance of the air-water direct tank. In this study, a simplified CFD-based model was established and validated between airstream and water surface within the tank, to analyze the heat and mass transfer and pressure drop processes. Meanwhile, regression models of the heat transfers rate, mass transfer rate and pressure drop were developed by uniform design method based on three parameters: installation position, tilt angle, and height of the deflector, in order to analyze the influences of these three parameters on the heat and mass transfer and pressure drop of the tank. Finally, all three optimal structural parameters of the deflector were obtained based on the proposed comprehensive evaluation index using a genetic algorithm. The results showed that the model established for air-water direct contact adopted well to predict the heat and mass transfer and pressure drop performance between airstream and still water surface. Furthermore, the results found that the flow field inside the water tank was affected by the deflector's structure, which affected the heat and mass transfer performance. The simulation results suggested that the deflector's optimal structural parameters are 8 mm of installation position, 88 ° of tilt angle and 19 mm of height, respectively, within a given extent in this study.

This study explores urban forestry as a maintenance practice capable of enhancing more-than-human commons in the city. Focusing on the places associated with tree care, the methodology takes as a case study the Tokyo Metropolitan Parks, conducting quantitative and qualitative analysis through the means of immersive field work and questionnaires, to reveal how urban forestry practices materialize within the parks. Regarding the spatial relations between humans and/or non-humans with resources, different Urban Forestry Elements (UFE) have been found, as well as their collection in groups within the parks forming Urban Forestry Assemblages (UFA). The paper creates a comprehensive framework that reveals these places for urban forestry as important beacons for urban commoning.

This study focuses on the development and analysis of a real-time updated operations strategy of a distributed energy system (DES). Owing to the relevant Chinese policy of electrical transmission and distribution, combined cooling, heating, and power system (CCHP) and photovoltaic (PV) systems are not currently allowed. However, with the Chinese supply-side power grid reform, the permissions for connections between DESs and utilities are gradually evolving. By performing building simulation and using mixed integer linear programming (MILP), a real-time updated operation strategy of a DES is established. Then, considering the DES from Tianjin Eco-city as a case study, a comparative analysis between this updated strategy and the current operation strategy is performed by evaluating three factors: economic efficiency, energy consumption, and CO2 emission. The results show that the updated strategy can reduce 29.12% of electricity time-of-use cost, 10.11% of total fuel consumption, and 18.40% of CO2 emission during the cooling season. Besides, a method of “rolling load forecasting” for DES by using Support vector regression machine (SVR) is proposed and discussed. The testing shows that the Mean Absolute Percentage Error (MAPE) is below 7.5%. And when the training sample is large, the particle swarm optimization algorithm can be used to shorten the modeling time of the air conditioning load forecasting model.

In this article, an attempt has been made to compare AAC blocks as a replacement material to red bricks. Different forms of experiments have been used to equate the properties of AAC blocks to those of other blocks. AAC blocks have a lower density than standard bricks for experimental verification, but they have a higher compressive strength than traditional bricks, which tends to reduce the structure's dead load. It has been found that the expense of construction is lowered by 15% to 20% when AAC blocks are used instead of other construction materials.

Building construction includes wide range of activities, such as extracting materials, treating and utilising them for construction, executing and operating the building and finally demolishing it after its life span. All these process results in enormous consumption of available resources and generate large amount of green house gases. This apparently results in global warming and resource depletion. Green buildings are considered as the optimal solution to overcome the negative effects of construction industry over the environment. Green buildings have manifold benefits in different sectors such as environment, economic and social. Hence many construction sectors across the world have now leaned towards green construction. In recent decades exponential growth of green buildings is observed globally. Though green building has attained considerable growth, there are several hurdles and challenges need to be faced from the constructor side. Also, the current management practices adopted in conventional building may not satisfy the requirements of the green building. The main theme of the paper is about barriers and project management practices in green building industry, since the other things are only supporting elements it is not included in the abstract. The design complexity in green building requires more modification in the existing project management practices. This paper listed out the barriers faced by the green building constructors as well as project management practices needs to be adopted to achieve green goal.

Uniform ventilation is important for the safety of long tunnel in underground buildings, it is difficult to install the large size air duct to ensure the centerline of each cross-section of the traditional variable cross-section ventilation system(VCVS) superimposed on the same horizontal axis, which is significant to the ventilation uniformity, energy consumption and installation convenience of the VCVS. On the contrary, each cross-section of the Equal Cross-section Ventilation System (ECVS) has the same horizontal axis, therefore, it is more convenient to manufacture and install the large size air duct in the underground long tunnel and achieve uniform ventilation. This study proposes an ECVS, using computational fluid dynamics(CFD) numerical simulation analyzed the influences of main duct velocity, aspect ratio, and outlet numbers on uniformity and energy consumption per unit air volume(ECPV). It revealed that when each ventilation equalizer's valve Angle β is given, uniformity of air supply decreases slightly with an increase in the inlet velocity. When the air supply main duct aspect ratio increases, the outlet velocity standard deviation range is from 0.22 to 0.34. When outlet numbers N=7~12 and β are constant, air supply uniformity and resistance coefficient ξ also decrease with the decrease of outlet numbers. The outlet number has a significant influence on the uniformity of system air supply, main duct velocity, and aspect ratio are relatively small. ECPV is positively correlated with the main duct velocity and outlet number, and is negatively correlated with aspect ratio.

The investigation is intended to develop a green masonry mortar using fine recycled aggregate (FRA) for sustainable building construction. The FRA was obtained from the demolished concrete debris and its influence in shear bond strength of brick masonry was evaluated to predict the suitability. The shear bond strength was determined using the masonry triplet specimens in stage-I without applying pre-compressive stress for finding the optimum replacement level of FRA and with pre-compressive stress value of 0.2, 0.4, 0.6 and 0.8 N/mm2 for finding the angle of friction in stage-II. The masonry mortar was prepared by replacing the river sand at the rate of 10%, 20%, 30%, 40% and 50% using FRA. Three different bricks were used for investigation based on its strength. The triplet specimens were casted with 12 mm and 18 mm mortar thickness and the specimens were cured 28 and 56 days. It was evidenced from the investigation that the substitution of recycled aggregate was influenced the shear bond strength of masonry structures and the optimum replacement level was predicted using the relationship between the dosage of recycled aggregate and the shear bond strength and the factors influencing the shear bond strength of brick masonry was decided in the order of Mortar strength > Brick strength > Mortar thickness with 20% replacement of river sand by recycled aggregate.

In most of the countries, the irregular building construction is popular for fulfilling both aesthetic and functional requirements. However, the evidence of past earthquakes in Nepal and the globe demonstrated the higher level of seismic vulnerability of the buildings due to irregularities. Considering this fact, the present study highlighted the common irregularities and its effect on reinforced concrete building response. The effect of structural irregularities was studied through numerical analysis. The geometrical, mass and stiffness irregularities were created by removing bays in different floor levels and removing the columns at different sections respectively. In this study, the numerical models were created in finite element program SAP2000. The structural performance was studied using both non-linear static pushover and dynamic time history analysis. The results indicate that the level of irregularities significantly influenced the behavior of structures.

This paper utilises non-linear finite-element analysis with three-dimensional (3D) solid elements to gain insight into the role of shear reinforcement in increasing punching shear resistance at internal columns of flat slabs. The solid element analysis correctly captures the experimentally observed gradual decrease in concrete contribution to shear resistance with increasing slab rotation and the failure mode but is very computationally demanding. As an alternative, the paper presents a novel approach, in which 3D joint elements are combined with non-linear shell elements. Punching failure is modelled with joint elements positioned around a control perimeter located at 0.5d from the column face (where d is the slab effective depth). The joint elements connect the nodes of shell elements located to either side of the punching control perimeter. The punching resistance of the joints is related to the slab rotation using the failure criterion of the critical shear crack theory. The joint-shell punching model (JSPM) considers punching failure both within the shear-reinforced region and due to crushing of concrete struts near the support region. The JSPM is shown to accurately predict punching resistance while requiring significantly less computation time than 3D solid element modelling.

Collaborative innovation has become an innovation paradigm to improve innovation performance and firms’ economic output. However, there is relatively little research investigating stakeholders’ drivers for engaging in collaborative innovation and the relative importance of drivers in infrastructure megaprojects. This research aims to address this gap by identifying the drivers for collaborative innovation and their relative importance in the context of infrastructure megaprojects. We adopt the literature review and questionnaire survey methods to identify drivers, the Relative Importance Index to rank them, and exploratory factor analysis to group them. The results show that 18 drivers are grouped into 6 dimensions. Their rankings are as follows: responding to project and clients’ requirements, improving efficiency, gaining rewards, learning, responding to competition, responding to environmental changes. The research contributes to stakeholders’ drivers to engage in collaborative innovation and the relative importance of drivers in the context of infrastructure megaprojects. Identifying and prioritizing stakeholders’ drivers can provide practitioners with suggestions on managing the collaborative innovation process in infrastructure megaprojects.

In this study, a combined strengthening technique is used to improve the flexural performance of prestressed concrete beams using CFRP sheets as EBR and prestressed steel strands as NSM. Seven prestressed beams were tested under four-point loading with one control specimen, one EBR CFRP sheet strengthened specimen, one NSM steel strand without prestress strengthened specimen and four specimens strengthened with a combination of EBR CFRP sheet and NSM steel strands prestressed from 0% to 70% of their tensile strength. The flexural responses and failure modes of the specimens were investigated and the variations due to the level of prestressing force in the PNSM steel strands were also assessed. A finite element model (FEM) was developed using ABAQUS to verify the flexural responses of the strengthened specimens. The test results revealed that the combined strengthening technique remarkably enhanced the flexural performance of the specimens. The serviceability, first crack, yield, and ultimate load capacities improved up to 44%, 49%, 55% and 70%, respectively when compared with the control specimen. The combined technique also ensured the flexural failure of the specimens with significant enhancement in stiffness and energy absorption. The results of the FEM model exhibited excellent agreement with the experimental results.

Due to the wide range of opportunities, collaborations, and challenges offered by the international construction sector, interest in international construction is on the rise. Construction companies must be able to carry out international construction projects (ICPs) more effectively and efficiently. However, executing ICPs is more challenging than executing domestic construction projects. Considering the peculiarities of the construction industry and the associated complexity of construction projects, construction companies should decide on international capability and the selection of an ICP through a careful evaluation of their critical success factors (CSFs). Most of the previous research deals with the concept of CSFs in the context of project management in general, but few studies have identified CSFs for ICPs. To fill that gap in current research, the main objective of this study was to identify and group CSFs for ICPs. A total of 37 CSFs were identified after conducting a detailed literature review and a pre-pilot study. A new framework of CSFs for ICPs was proposed following primary research, which was conducted through in-depth interviews with leading experts in international projects. Although the constructability/complexity factor of the project received the highest rating in terms of importance to the success of the ICP, the next most critical factors were found to be external factors, such as local contractor/subcontractor, investor, and presence of a foreign partner. The results of this research may help participants involved in ICPs to improve their understanding of the international construction environment and deliver more successful ICPs.

In the midst of challenges facing affordable, safe and sustainable housing development, there is a continuous increase in the vast amounts of carton papers, melon seed husks, and groundnut shells discarded as waste materials. This is of great concern, especially, as such residues are under-utilised and their improper disposal creates grave problems. Thus, this work was designed to assess the feasibility of solving the emerging problems by valorising the said wastes into value-added products that can be used for building construction. Samples containing varying weight proportions of waste carton paste (WCP) and melon seed husk (MSH) were developed using Topbond as binding agent. Other samples were similarly fabricated but with groundnut shell (GNS) as a component. From the results of tests performed to investigate strength and heat transfer behaviour of each developed sample, it was observed that nailability remained 100% irrespective of the composite formulations adopted. In other cases, the test results varied according to WCP loadings. Though samples containing MSH appeared to be more efficient than their counterparts with GNS content for thermal insulation, the observed differences in the results were statistically insignificant. Aside being sustainable and inexpensive, it was found generally that the afore-mentioned wastes are promising alternative raw materials for production of medium-density panels that are environmentally-friendly and also suitable for use as either ceiling or interior partition boards for effective thermal insulation in buildings. Such undertakings have the potential to minimise the adverse effects that could be caused by the wastes in question.

An application of geometric mixed additive-multiplicative models for lung cancer risk modeling under combined action of radon and smoking is justified in this paper. The geometric mixed model allows: 1) to reduce the discrepancies between estimates of the lung cancer risk for males and females, 2) to predict the population risk under condition of the varying smoking prevalence and changing average indoor radon concentration level. Using the geometric mixed model, the calculation of the lung cancer risks for the Russian Federation population was carried out for different percentages of smokers among the population, an increase in life expectancy, and a change in the average radon concentration level in residential buildings. Assuming that currently rounded average indoor radon concentration in Russia is 50 Bq/m3, the contribution of radon to total mortality in 2009 was 0.46% and 0.20% for male and female, respectively. Modeling has shown that the effect of lung cancer mortality reducing due to the predicted decrease in the proportion of smoking population will partly be offset by an increase in the realization of lung cancer risk with the life expectancy increase. For a hypothetical situation, when the entire population maintain a healthy lifestyle and mortality from cardiovascular, oncological, infectious diseases, diseases of the respiratory tract and from external causes has significantly decreased, the contribution of radon exposure to total mortality will increase to about 0.8%. If the average level of radon in buildings will increase due to energy-efficient technologies widespread implementation in building construction, the contribution of radon to total mortality will be even more noticeable.

Any systems can be expressed by and connected with information. For the safety education system, doing so is essentially a process of safety information dissemination and cognition. Therefore, information is the core of the safety education system. At present, the key factors affecting the effectiveness of safety education are safety demand analysis information, the dissemination and cognitive processes of safety information and information feedback. Research on the construction of a framework model for safety education under the guidance of information flow clears and classifies information-related elements of the safety education process. Therefore, it is conducive to the construction of a safety education system to improve its management level and, through the rational use of information technology, to improve the conversion rate of safety information into safety behaviour. Based on a systematic review and comparison of the existing research perspectives on safety education and information-flow-based safety education (IFSE), this paper analyses the reasons why we need a new perspective on safety education. We introduce information flow into the safety education framework model. The fundamental and expanding elements of safety education propagation are examined and deduced based on information theory. Combined with the connotations of safety education and information flow, this paper analyses the implementation steps of IFSE and applies them to the safety education of new employees in metal and nonmetal mines. In the micro-design, virtual reality technology is used to integrate safety education content and information technology. A new perspective on safety education is created; then, the framework model of IFSE, its implementation steps and models of the processing and utilization processes of safety education are constructed. IFSE is a new perspective for realizing safety education in practice, and the framework model of IFSE provides rigorous theoretical knowledge. Of course, to improve IFSE in practice, more scientific and detailed evaluation methods need to be introduced. This paper is helpful for guiding the safety education theory research from “trivializes situated” to “systematic” and for guiding the design, implementation, assessment and optimization of the safety education practice.

Building information modeling (BIM) and prefabricated construction (PC) are increasingly applied in the construction industry. Recent academic and industrial efforts indicated that the application of BIM and PC is a solution to reduce lifecycle costs, reduce waste, increase productivity and improve quality in construction. Although previous studies have advanced the integration of BIM and PC, extensive research scope and scattered research topics cannot form an overall picture of knowledge structure. Hence, this study aims to establish an up-to-date synthesis of the latest research on BIM for PC and identify the research gaps and future needs. First, a database with 103 journal articles on BIM for PC was established through data collection; second, a bibliometric analysis was applied to determine the top journals, articles and to map the latest mainstream research. Last, a qualitative analysis was used to determine the mainstream research areas and identify the research gaps and future needs. This study may contribute to enrich our body of knowledge on the use of the techniques in conjunction, help researchers and builders to understand the latest progress of BIM for PC research in timely fashion, and promote the integration of BIM with PC and other cutting-edge technologies moving forward.

The incorporation of protocols in heritage building preservation is important for the definition of preventive conservation actions. Such integration is needed to avoid restoration actions and to promote preventive maintenance instead of corrective maintenance actions. This paper presents the application of an innovative digital management system using artificial intelligence that can quantify the suitability of a sample. This kind of application can support the maintenance management of buildings and minimise human error in data collection. The fuzzy system showed slight differences between the members of the expert panel during the in-situ visual inspection. These results indicate that, despite differences between various experts' evaluation of a building, the proposed digital method helps minimise the uncertainty in the results. The paper highlights input variables, which present high dispersion (load state modification, fire and oc-cupancy), and input parameters, which present low dispersion (preservation, roof design and overloads). Fuzzy systems can adequately manage the uncertainties associated with different experts' assessment of sample that present constructive homogeneity. This study can give advantages to stakeholders during the inspection, diagnosis and evaluation stages in the improvement of mitigation policies focused on preventive maintenance programs dedicated to the resilience of heritage buildings, specifically churches emplaced in Chile. © 2021 The Author(s). Published by Vilnius Gediminas Technical University.

In most countries, buildings are responsible for significant energy consumption where space heating and air conditioning is responsible for the majority of this energy use. To reduce this massive consumption and decrease carbon emission, thermal insulation of buildings can play an important role. The estimation of energy savings following the improvement of a building's insulation remains a key area of research in order to calculate the cost savings and the payback period. In this paper, a case study has been presented where deep retrofitting has been introduced to an existing building to bring it closer to a Passivhaus standard with the introduction of insulation and solar photovoltaic panels. The thermal performance of the building with its improved insulation has been evaluated using infrared thermography. Artificial intelligence using deep learning neural networks is implemented to predict the thermal performance of the building and the expected energy savings. The prediction of neural networks is compared with the actual savings calculated using historical weather data. The results of the neural network show high accuracy of predicting the actual energy savings with success rate of about 82% when compared with the calculated values. The results show that this suggested approach can be used to rapidly predict energy savings from retrofitting of buildings with reasonable accuracy, hence providing a practical rapid tool for the building industry and communities to estimate energy savings. A mathematical model has been also developed which has indicated a life-long monitoring will be needed to precisely estimate the benefits of energy savings in retrofitting due to the change in weather conditions and people's behaviour.

The purpose of this research is to detect fraudulent financial reporting in the property, real estate, and building construction sectors listed on the IDX based on the perspective of the fraud pentagon theory. The data collection technique used purposive sampling and data analysis using logistic regression. The results indicate that external pressure factors, ineffective monitoring, quality of external auditors, auditor turnover, rationalization proxied by auditor opinion, change of directors, and political connections affected FFR. Meanwhile, financial target factors, financial stability, institutional ownership, and the frequency of the appearance of the CEO image in the annual report do not affect FFR.ABSTRAKPenelitian ini bertujuan untuk mendeteksi kecurangan pelaporan keuangan pada sektor properti, real estate, dan konstruksi bangunan yang terdaftar di BEI berdasar perspektif teori fraud pentagon. Pengumpulan data menggunakan teknik purposive sampling dan analisis data menggunakan regresi logistik. Hasil penelitian menunjukkan bahwa faktor tekanan eksternal, pengawasan yang tidak efektif, kualitas auditor eksternal, pergantian auditor, rasionalisasi yang diproksikan dengan opini auditor, pergantian direksi, dan hubungan politik berpengaruh terhadap FFR. Sedangkan faktor target keuangan, stabilitas keuangan, kepemilikan institusional, dan frekuensi kemunculan gambar CEO dalam laporan tahunan tidak berpengaruh terhadap FFR.

The construction industry is known for its high rate of accidents. Among the different possible causes of this situation, we could find lack of sleep and fatigue. Chronic sleep deprivation is a determining factor in the deterioration of vigilance and alert, and consequently a risk factor for occupational accidents. Fatigue is the answer of our organism to sustained physical and mental stress. Regretfully, those topics have been ovelooked in the construction industry. The objective of this study is to understand better these phenomena, such as sleep duration and fatigue, and whether they are interrelated, and to propose strategies to mitigate them and contribute to the reduction of accidents in construction projects. We worked with 154 male construction workers from one Chilean construction company. To assess sleep quality, we used the Pittsburgh Sleep Quality Index (PSQI). To evaluate fatigue, we used a personal computer version of the Psychomotor Vigilance Test (PC-PVT) that measures alertness and vigilance. This 5-minute test was performed on construction workers on-site in the morning. Those people who took part in the test were classified into various groups according to self-reported sleep hours, namely: 7–9 h (26%), 5–7 h (61.7%), and

The nondestructive testing technology of generated acoustic emission (AE) signals for wood is of great significance for the evaluation of internal damages of wood. To achieve more accurate and adaptive evaluation, an AE signals classification method combining the empirical mode decomposition (EMD), discrete wavelet transform (DWT), and linear discriminant analysis (LDA) classifier is proposed. Five features (entropy, crest factor, pulse factor, margin factor, waveform factor) are selected for classification because they are more sensitive to the uncertainty, complexity, and non-linearity of AE signals generated during wood fracture. The three-point bending load damage experiment was implemented on sample wood of beech and Pinus sylvestris to generate original AE signals. Evaluation indexes (precision, accuracy, recall, F1-score) were adopted to assess the classification model. The results show that the ensemble classification accuracies of two tree species reach 94.58% and 90.58%, respectively. Moreover, compared with the results of the original AE signal, the accuracy of the AE signal processed by the methods proposed is increased by 27.68%. It indicates that the EMD and DWT signal processing methods and selected features improve the classification accuracy, and this automatic classification model has good AE signal recognition performance.

Shallow geothermal systems use the thermal inertia of the earth to provide a temperature gradient between the ambient conditions and the underground soil. This thermal inertia can be used by the heat exchangers to provide space heating and cooling during the winters and summers. This paper provides a brief but broad overview of the different active and passive technologies involved in the use of heat exchangers for HVAC in order to achieve a near net zero energy building. Firstly the different types of ground heat exchangers and heat pumps are introduced along with the relevant studies of significance in this field. It has been demonstrated that the different types of heat exchangers can be integrated with thermally active building envelopes and renewable energy resources to significantly minimize the building energy use. Finally a pathway has been devised for use of ground heat exchangers to realize a net zero energy building.

Due to production particularity in industrial buildings, high concentrations of particulate matter are always important environmental issues. Long-term exposure to such hazardous environment may lead to respiratory and cardiovascular diseases. Mechanical ventilation plays a vital role in reducing indoor particulate matter concentrations. However, the current industrial ventilation generally has the disadvantage of low ventilation efficiency and high energy consumption. In this study, we proposed a ventilation design by integrating supply and exhaust ventilation (i.e., SEV), and further investigated the effects of combined velocities on both indoor particles removal and energy efficiency. Computational Fluid Dynamics (CFD) coupled with Discrete Phase Model (DPM) was employed. The RNG k-e model was adopted to simulate airflow field. Lagrangian method was used to trace particles’ dispersion processes. A series of cases were conducted under ventilated conditions with combinations of different supplied velocities of 0.75, 1.12, 1.50 and 1.87 m/s, and exhausted velocities of 0, 0.28 and 0.56 m/s. Temperature effects were not considered in this work. The quantification of combined effects of supply velocity and exhaust velocity were investigated in terms of particle removal efficiency as well as energy saving. Results showed that combined effects of supply velocity and exhaust velocity can improve the ventilation efficiency by 20%-40% compared to the conventional supply ventilation without exhaust velocity. Moreover, the reasonable design of integrated velocities will save up to 70% energy while keeping the same ventilation efficiency of SEV. These findings will be of great importance for energy-efficient design for industrial ventilation systems.

The implementation of construction activities, especially building construction work, has a high risk of accidents because each stage of the work contains many potential hazards that can be detrimental. This study aims to determine the highest occupational accident risk and its control in column, beam and floor slab work. The research method was carried out through field observations as well as interviews and surveys from several sources. The results of this study are jobs that contain the highest risk value, namely in the steps of installing work and dismantling column formwork, installing scaffolding, and installing wooden beams on beam and floor slab work where each step of this work has a risk level value of 6, this has high level of risk . For hazard control, the contractor carries out several work programs with the aim of reducing the potential for work accidents. As for the program in the form of Toolbox, Safety Patrol, Safety Weekly Meeting, Safety Talk, Fooging and Extrapuding.

Australia's national energy system is heavily reliant on coal-fired power plants and requires quick action to decrease CO2 emissions in order to meet the Paris climate change agreement by 2030. As a good alternative to coal power, renewable resources can produce the required energy for Australia while keeping the environment clean. The annual amount of falling solar irradiation in Australia is a few thousand times higher than its energy consumption, but the amount of the collected solar energy is unsatisfactory. In Perth, the sunniest city in Australia, one-third of the residential dwellings have roof-mounted solar collector systems. However, there have been limited studies into the integration of these systems in building design and it is still unknown which roof design can deliver maximum efficiency based on the local environmental conditions. Therefore, the aims of this study are to determine the optimum residential roof design in Perth, Western Australia and to maximise extracted solar power throughout a year. To reach this aim, a combination of analytical modelling, numerical simulation, and evolutionary algorithm methods have been selected. At first, a series of detailed mathematical calculations were performed in Excel to find the optimum solar collector mounting settings. In the numerical simulation, the examination was repeated in the Rhino-Grasshopper interface to verify the earlier findings and calibrate the chosen simulation package with the help of parametric architecture. In the last step, a wide range of housing roof shapes has been tested by evolutionary algorithm plugin-Galapagos, to find the optimum roof shape design in the given context. Our results show that, unlike the traditional approach and common belief, a roof shape with a 25-degree tilt angle, 170-175 azimuth angle, and aspect ratio of 1:1.2 is optimum to gain maximum solar gaining annually. Moreover, this study advances the knowledge of solar capturing by suggesting a new parameter -oblique angle- in finding the optimum roof shape design. After evaluating the importance of the mentioned factors, it is found that, after tilt angle, the oblique angle is the most effective parameter in rooftop solar gaining, higher than roof aspect ratio and azimuth angle. In conclusion, our results demonstrate that an ‘oblique shed roof design’ can generate 15.7% higher solar radiation compared to the base case. The findings of this study can be applied by architects, construction companies, and householders to optimize the solar gaining in the future of the residential building in Perth.

Wind catchers used in various countries in Middle East and North Africa in order to improve indoor air environment and to reduce reliance on cooling load. However, nowadays they are used across the globe with modern shapes and advanced techniques. The study focuses on investigating new and innovative shapes of wind catchers to improve air speed indoors which will elevate indoor comfort and air quality in buildings. The study used computer modeling CFD and a real model experiment to conduct the study. The study highlighted that curved shapes have highest pattern of wind speed driven, especially curved shape with double inlets. In addition, the study showed that octagon shape has the lowest pattern of wind speed driven because of its various sides which prevent air to flow easily inside the tunnel.

Rapid increase of urban underground constructions has a great consideration of underground environment safety and how to expel toxic gasses out of tunnels effectively. The utility tunnel is a typical urban tunnel construction with multiple underground pipelines including gas pipelines, and it is necessary to investigate characteristic of gas diffusion and monitor gas leakage to ensure tunnel safety. In this study, the experimental measurements of airflow and gas distributions were conducted in a 10 m full-scaled utility tunnel mockup, and gas diffusion characteristic was also investigated. Numerical simulation of utility tunnel leakage was also conducted by computational fluid dynamics (CFD). Different turbulence models and different air supply diffuser models were compared via the experimental results based on visualization and the relative root-mean-square error (RRMSE) index, which quantitated the difference between the numerical and experimental results. The results showed that the standard k − e turbulence model and random air opening model could provide better results than other models. According to the experimental data analysis, it was necessary to consider the optimization of monitoring detector arrangements in actual utility tunnels. This study provided basic experimental data and the validated numerical model for the leakage source identification and underground tunnels simulation research.

Introduction. In the modern socio-economic and geopolitical development of Russia, the development of industry comes to the fore. Among the many industries, ammonia stations play the most important role. The main regularities of the process of pumping and preparing water. The process consists of six stages, this article discusses the automation of stages 1 and 2: for water treatment and pumping it out with pumps H1 and H2 from the tank P2. Products in the form of purified water are the most important criteria for subsequent production at an ammonia plant, therefore, increased requirements are imposed on the quality of finished products, including the quality of purification of the water used with the help of nanofilters. The required quality cannot be achieved without control the process in an automated mode. Development of a neural network. To control the converters frequency values during the preparation and pumping of water, an artificial neural network must be used. Its development was carried out in the Matlab environment in the Neural Network Toolbox package, input and output data were defined for this, data processing and preparation were performed, as well as the choice of the type and architecture of the neural network. The architecture of the Layer Recurrent neural network, the process of its construction and training in Matlab is described. Testing of neural networks. During testing of the Layer Recurrent network for the degree of their training, the smallest error was obtained for 30 neurons in the hidden layer. The proximity to the set values indicates the applicability of the network for controlling the parameters of frequency converters. Development of the neural network controller model in the Simulink package. The simulation of the control system in the Simulink package using a neural network controller with the Layer Recurrent architecture is performed. Checking the frequencies of the frequency converters H1 and H2 in Simulink for the level parameters in the tanks and in the tank LT1_вх, LT2_вх, LT3_вх showed that the object model works correctly, thus, the simulation of the neural network showed that the training was successful. Conclusion. As a result of the conducted research, an artificial neural network was developed to control the process of preparing and pumping water in the Matlab environment and a simulation of a neural network in the Simulink package.

Architects throughout the time being experienced many roles in different times, while there have always been unclear what architects underwent and practised was their actual duty. This research tries to find proper answers about architects' duties, roles, and struggles in the Iraqi Kurdistan region. For this reason, questionnaires were applied to ask both the architects and administrative managers in Sulaimani governorate/department of building construction. We find out that the main role of an architect in the Sulaimani governorate is mainly designing projects. However, they are involved in managerial roles as project supervisors destined by the governorate and also another role of the architect is checking the drawings of the projects designed outside of this administration office. Another finding was that the architects in the Sulaimani governorate or Iraqi Kurdistan region generally face the problem that their works are done by other specialists, which sometimes cause some domain faults in the works and do not have enough or proper area to work in.

Scope creep is the uncontrolled changes to scope that are difficult to be known and contribute to time and cost escalations during construction phase. Thus, preventing its causes would be an effici...

This study investigates the post-fire performance of steel reinforced concrete composite (SRC) columns used in building construction using experimental compression tests. Four conventional steel sections as I-shaped, Cross, Box, and Plus were considered as the steel core. For fire loading, all fabricated columns were subjected to five target temperatures, including 25°, 250°, 500°, 700°, and 900°C, and then the cooling phase of the columns was done under natural conditions. Then using pressure jacks, the compressive behavior including strength and axial deformation of each of them was measured, and force-deformation curves were plotted and investigated for each SRC column. The results of these tests showed that the compressive strength and the elasticity modulus of the columns decrease at higher temperatures. Also, the effect of the steel core was examined on the compressive strength. Among the tested sections, SRC columns with the Box-steel core showed a more recovery in its compressive strength and elasticity modulus, and hence, its performance was better than SRC columns with the other steel cores. Moreover, SRC columns with the Plus-steel core indicated the weakest compressive strength and elasticity modulus. Finally, some equations were proposed for the prediction of the compressive strength and elasticity modulus of SRC columns at different temperatures by applying gene expression programming (GEP modeling) to the results.

Increasingly, construction companies are using drone technology for a variety of purposes, including conducting aerial surveys and monitoring the activities of staff and subcontractors on the construction worksite. As the technology develops, newly adopted drone laws and the application of current laws to drone use are areas of concern as governments grapple to regulate the operators, manufacturers and systems. While the commercial benefits of using drones on the construction site are not fully understood or realised, companies need to keep abreast of changes to the legislation and regulations that govern drone usage. This paper reviews the regulatory and legal schemes for drone operation within the construction industry in the USA, the UK, Japan, Australia and Hong Kong. Drone technology, infrastructure, regulations and standards are continually evolving, with collaborative research and development across all these areas. While this offers exciting opportunities to private and public sectors worldwide, such rapid change and growth is a challenge for regulators, to ensure that regulations and infrastructures are in place in time to manage and meet these changes. The proposed research agenda offers a guide for future research on the legal aspects of drone operation for the construction sphere.

Purpose: This study aimed to analyze the implementation of the Building Construction Permit policy and to analyze the inhibiting factors for implementing the Building Construction Permit policy based on the Regional Regulation of South Timor Tengah regency Number 7 of 2015 in So'e city, South Timor Tengah regency. Research methodology: This research was qualitative research using a descriptive approach. The data were collected through interviews, observation and documentation. Results: The inhibiting factor for the implementation of the Building Construction Permit policy in So’e city, South Timor Tengah regency is the limited resources in the form of human resources, financial resources, operational resources, buildings that are not in accordance with spatial planning and many buildings that violate the boundary lines as well as public understanding of building permit regulations. Limitations: This study only analyzed the implementation of the Building Construction Permit policy based on the Regional Regulation of South Timor Tengah regency Number 7 of 2015 in So’e city, South Timor Tengah regency. Contribution: This research becomes scientific information for public administration program.

Building Information Modeling (BIM) has been acknowledged for promoting effectiveness and efficiency in project planning and management activities including design, bidding, and construction. Yet limited effort has been made to investigate the impacts of BIM implementation on corporate performance. Using the financial information of 314 Architecture, Engineering, and Construction (AEC) companies listed in the A-share market of China, this paper examines the economic benefits of BIM practice and assesses the influential mechanism of BIM implementation at the corporation level. The results reveal that BIM adoption contributes to better corporate profitability, especially in non-state-owned enterprises (non-SOEs). The positive impact of BIM implementation on profitability is achieved by the functions of promoting schedule efficiency and operation cost reduction. However, high initial BIM investment is still required in China's AEC companies at the current stage, and the effectiveness enhancement in corporation management has not been realized. By providing clear empirical evidence of the economic benefits of BIM adoption from a corporation perspective, this study might help improve top managers’ awareness, intention, or support of future BIM utilization in China's AEC companies.

The objective of this study is to analyse the impact of management practices on the productivity of building construction projects in India. The methodology adopted for this study is to identify and analyse the management practice attributes from the literature review and expert focus group interviews. The identified attributes were analysed and priorities using relative weight were given by the respondents. The collected data were further analysed using SPSS 21 software. The quantitative research methodology was adopted to analyse the collected data and the following tools and techniques were applied to the data: reliability analysis to check the consistency of data collected for this study and relative importance index (RII) to prioritise and rank the attributes based on the weighted average score given by the respondents. The findings of this study concluded that coordination between all stakeholders, ability to handle the crisis by the project managers, social skills of key team managers, timely payment of completed works and design capability and frequent design changes are the most significant attributes of management practice, affecting construction productivity and having a rating on the RII of 0.91, 0.90, 0.88, 0.87 and 0.87.

The rice straw burning in all the Egyptian governorates is seasonally occurring, an environmental disaster called the "Black Cloud". This study's main goal is to conduct the Life Cycle Assessment (LCA) and Building Information Modeling (BIM) methods. Thus, the LCA of four brick types: (1) fired clay, (2) cement, (3) sand, and (4) rice straw has been compared. The BIM has been used to gather the building construction components to build the four LCA scenarios using the PRe SimaPro. The results have been presented by the single score and weighting method using the IMPACT 2002+ method with midpoint and endpoint (Pt) results. (1) Regarding the midpoint results, the fired clay brick has recorded the worst environmental impact with 30.10 Pt. In contrast, the rice straw brick has verified the lowest effects with 1.31 Pt. (2). Regarding the endpoint results, the highest value of human health has been assigned to the fired clay brick type with 11.4 Pt and the rice straw brick with 0.633 Pt. The highest resource depletion impacts have been pointed out the fired clay and cement brick with 7.29 Pt and 6.53 Pt, respectively. A novel framework for integrating LCA and BIM has been conducted on a proposed building during the early phases. The article has also introduced an approach to eliminating the Egyptian life cycle inventory database shortage as the LCA applications in Egypt are scarce. Moreover, it can help the concerned legislative bodies and the decision-makers.

Introduction. Advanced technologies impress people’s imagination demonstrating the latest achievements (materials, methods, systems, technologies, devices etc.) that dramatically change the world. This, first of all, concerns nanotechnological inventions designed by scientists, engineers and specialists from different countries. Main part. The article provides an abstract review of patents. The results of creative activity of scientists, engineers and specialists, including inventions in the field of nanotechnology and nanomaterials, being implemented, allow achieving a significant effect in construction, housing and community services, and related sectors of the economy. For example, the invention «Composite material with oriented carbon nanotubes» refers to the area of composite materials which consist of polymer matrix and filler that is often presented by carbon nanotubes. The technical result is increased tensile strength of composite material due to formation of structure of oriented carbon nanotubes in polymer matrix. That is performed by means of flat-rate flow of direct current which destroys filler agglomerates. The specialists can also be interested in the following inventions in the area of nanotechnologies: a method to produce powder containing nanocrystalline cubic tungsten carbide; a method to produce porous graphene membranes and the membranes produced with this method; suppressor coating on the basis of polymer matrix with inclusion of carbon nanotubes and a method to produce it; a method to determine location of polyethylene gas pipeline and places of possible illegal tapping of those pipeline; a method to produce biphasic thermoelectric ceramics; electron-beam system of 3D radiant nanomodification for materials and articles; lab-on-fruit skin and lab-on-leaf towards recognition of trifluralin using Ag-citrate/GQDs nanocomposite stabilized on the flexible substrate: A new platform for the electroanalysis of herbicides using direct writing of nano-inks and pen-on paper technology; and others. Conclusion. One of the most challenging tasks the economy of every country face is to increase industrial competitiveness through technological upgrade. From the side of the state and companies the principal object to control in this process are the people and enterprises dealing with introduction of inventions and new technologies.

Split 2 is a significant part of urban and architectural heritage in Split and Croatia. This arises from the scope and reach of the rational urban planning and use of space, inventive architectural design focused on construction technologies, operations and materials which were mainly organized in concentric construction sites of housing developments and areas which predominantly featured standardized residential buildings and residential high-rises in the period from 1957 to 1968.

PurposeThis study aims to empirically validate five propositions about the benefits of three-dimensional (3D) visualizations for the management of subsurface utility projects. Specifically, the authors validate whether benefits from 3D in the literature of building construction project management also apply to subsurface utility projects and map them using a taxonomy of project complexity levels.Design/methodology/approachA multiple case study of three utility construction projects was carried out during which the first author was involved in the daily work practices at a utility contractor. 3D visualizations of existing project models were developed, and design and construction meetings were conducted. Practitioners' interactions with and reflections on these 3D visualizations were noted. Observational data from the three project types were matched with the five propositions to determine where benefits of 3D visualizations manifested themselves.FindingsPractitioners found that 3D visualizations had most merit in crowded urban environments when constructing rigid pipelines. All propositions were validated and evaluated as beneficial in subsurface utility projects of complexity level C3. It is shown that in urban projects with rigid pipelines (project with the highest complexity level), 3D visualization prevents misunderstanding or misinterpretations and increases efficiency of coordination. It is recommended to implement 3D visualization approaches in such complex projectsOriginality/valueThere is only limited evidence on the value 3D visualizations in managing utility projects. This study contributes rich empirical evidence on this value based on a six-month observation period at a subsurface contractor. Their merit was assessed by associating 3D approaches with project complexity levels, which may help utility contractors in strategically implementing 3D applications.

As a data tool applicable to the full life-cycle of construction engineering and management, Building Information Modeling (BIM) has great potential for significantly increasing project productivity and performance. Awareness of BIM application hotspots and forecasting its trends can drive innovations in construction field. Using patents as data resources, this study develops an effective framework integrating the citation network analysis and the topic clustering technology to identify BIM application information and forecast its trends. This framework comprises three-step analysis:(1) quantitative characteristic analysis of patent outputs; (2) Social Network Analysis (SNA)-based co-occurrence network analysis; and (3) identification of BIM topics using a Latent Dirichlet Allocation (LDA). Finally, the case demonstrates the effectiveness of this framework contributing to promote technological development and innovation of BIM. The contributions of this study are threefold: (1) an innovative text mining-based framework for BIM patent analysis in construction is developed; (2) patents that have focused on identifying the application hotspots and development trend of BIM in accordance with our developed framework are reviewed; and (3) a signpost for technological development and innovation of BIM is provided.

Large infrastructure investments are expected to be of sustained value to society for a long time. Such investment projects include, for instance, hospitals, tunnels, sport arenas, power plants, roads, railways, and bridges. They involve a complex organization of contracts and agreements. The client is expected to plan, procure, and determine the critical steps of a project, while the contractor should solve issues raised by the client. Many of these agreements are path-dependent and reflect past routines, experiences, and contacts. As such, many investments tend to return to similar sources instead of replacing routines and collaborations that did not work. This can cause change orders that furthermore reflect consequences such as cost and time overruns. While much is known about these effects in construction projects, this paper sheds light on the drivers of change orders. We build upon a sample of 234 observations responding to a survey on investment planning. The results show that project assumptions are often wrong and inadequate in large investments. Such wrong assumptions are caused by interpersonal and leadership issues, poor planning, or sometimes even intentional profit-seeking. Our results show that clients and contractors have different perceptions and enter contractual obligations differently. The implication is, therefore, that better routines of documentation, more frequent feedback, and more accurate or precise standards may close the gap between planning and what is actually achieved. More precise contractual agreements may also create a better process to procure, manage projects, and allocate resources.

Introduction. Currently, both abroad and in Russia, there is a “general digitalization” not only of certain types of activities, but also of objects of the technosphere, for example, “smart houses”, “safe cities”, etc. However, the “creators” of these objects violated the main principle of automation of Academician V.M. Glushkov, which says: you cannot automate the mess! Therefore, the authors of this article made an attempt to “eliminate clutter” in the automation of engineering systems in the residential sector. Methods, models and tools. Based on the analysis of the engineering systems of multi-apartment residential buildings and individual residential buildings, as a result of the functioning of which not only the delivery of “life support benefits” is carried out, but also fire-energy and environmental damage occurs, a methodology for “intellectualization” of the accounting means for the supplied resources has been developed for diagnostics and suppression of fire and energy harm with the help of modern nanotechnology and, thus, prevention of fires and explosions in the residential sector. Results and discussion. The methodology of “intellectualization” is based on the results of a system analysis of the “functioning of the residential sector” (apartment buildings and individual residential buildings), which made it possible to “discover” the dialectical unity of benefits and harms from consumed energy resources (electricity, domestic gas, hot and cold water), as well as to carry out a systemic synthesis of nanotechnologies and means of “isolation and suppression” of fire and energy harm. The novelty of the research is protected by RF patents. Conclusion. The proposed approach allows “eliminating the disorder before the automation” of engineering systems of multiapartment residential buildings and individual residential buildings, by “intellectualizing” metering devices and optimizing nanotechnologies for suppressing fire and energy harm that brings socio-economic losses