Search results for: construction of indices

Authors: M. C. Theong, F. L. Ang, G. J. Muga

Abstract:

Growth of firms is influenced by environmental changes such as the global and national economy. On the other hand, it indicates the economic situation of a country. Therefore, it is imperative for firms to be sensitive to changes and to stay competitive and remain compatible with the environment. The Malaysian construction industry is prone to environmental changes due to its complexity. In order to survive in the construction industry, focus on the development of the firms themselves to achieve long term their long term goals is vital besides maximizing profits. The objective of this paper is to measure growth of the public listed construction companies in Malaysia and to investigate the development of the companies with highest, moderate and lowest growth. Growth is measured based on the companies' sales between year 2008 and 2012 collected via secondary data collection method. Findings show that the highest average growth created is 235.20 % while the lowest average growth is -22.75%. The construction companies remained active in the construction industry by implementing different sets of strategies and involving in several types of construction projects.

Keywords: growth, Malaysian construction industry, public listed companies, sales

Procedia PDF Downloads 387

Authors: Jonggeon Lee, Sungho Tae, Sungjoon Suk, Keunhyeok Yang, George Ford, Michael E. Smith, Omidreza Shoghli

Abstract:

In recent years, research to reduce carbon emissions through quantitative assessment of building life cycle carbon emissions has been performed as it relates to the construction industry. However, most research efforts related to building carbon emissions assessment have been focused on evaluation during the operational phase of a building’s life span. Few comprehensive studies of the carbon emissions during a building’s construction phase have been performed. The purpose of this study is to propose an assessment method that quantitatively evaluates the carbon emissions of buildings during the construction phase. The study analysed the amount of carbon emissions produced by 17 construction trades, and selected four construction trades that result in high levels of carbon emissions: reinforced concrete work; sheathing work; foundation work; and form work. Building materials, and construction and transport equipment used for the selected construction trades were identified, and carbon emissions produced by the identified materials and equipment were calculated for these four construction trades. The energy consumption of construction and transport equipment was calculated by analysing fuel efficiency and equipment productivity rates. The combination of the expected levels of carbon emissions associated with the utilization of building materials and construction equipment provides means for estimating the quantity of carbon emissions related to the construction phase of a building’s life cycle. The proposed carbon emissions assessment method was validated by case studies.

Keywords: building construction phase, carbon emissions assessment, building life cycle

Procedia PDF Downloads 754

Authors: Benjamin Goldsmith, Felix Heisel

Abstract:

The building industry must reduce its emissions in order to meet 2030 neutrality targets, and modular and/or offsite construction is seen as an alternative to conventional construction methods which could help achieve this goal. Modular construction has previously been shown to be less wasteful and has a lower global warming potential (GWP). While many studies have been conducted investigating the life cycle impacts of modular and conventional construction, few studies have compared different types of modular assembly and construction in order to determine which offer the greatest environmental benefits over their whole life cycle. This study seeks to investigate three different modular construction types -infill frame, core, and podium- in order to determine environmental impacts such as GWP as well as circularity indicators. The study will focus on the emissions of the production, construction, and end-of-life phases. The circularity of the various approaches will be taken into consideration in order to acknowledge the potential benefits of the ability to reuse and/or reclaim materials, products, and assemblies. The study will conduct hypothetical case studies for the three different modular construction types, and in doing so, control the parameters of location, climate, program, and client. By looking in-depth at the GWP of the beginning and end phases of various simulated modular buildings, it will be possible to make suggestions on which type of construction has the lowest global warming potential.

Keywords: modular construction, offsite construction, life cycle analysis, global warming potential, environmental impact, circular economy

Procedia PDF Downloads 171

Authors: Ahmed Stifi, Sascha Gentes, Fritz Gehbauer

Abstract:

The construction industry is perhaps one of the oldest industry of the world. The ancient monuments like the egyptian pyramids, the temples of Greeks and Romans like Parthenon and Pantheon, the robust bridges, old Roman theatres, the citadels and many more are the best testament to that. The industry also has a symbiotic relationship with other . Some of the heavy engineering industry provide construction machineries, chemical industry develop innovative construction materials, finance sector provides fund solutions for complex construction projects and many more. Construction Industry is not only mammoth but also very complex in nature. Because of the complexity, construction industry is prone to various tribulations which may have the propensity to hamper its growth. The comparitive study of this industry with other depicts that it is associated with a state of tardiness and delay especially when we focus on the managerial aspects and the study of triple constraint (time, cost and scope). While some institutes says the complexity associated with it as a major reason, others like lean construction, refers to the wastes produced across the construction process as the prime reason. This paper introduces corruption as one of the prime factors for such delays.To support this many international reports and studies are available depicting that construction industry is one of the most corrupt sectors worldwide, and the corruption can take place throught the project cycle comprising project selection, planning, design, funding, pre-qualification, tendering, execution, operation and maintenance, and even through the reconstrction phase. It also happens in many forms such as bribe, fraud, extortion, collusion, embezzlement and conflict of interest and the self-sufficient. As a solution to cope the corruption in construction industry, the paper introduces the integrity as a key factor and build a new integrity framework to develop and implement an integrity management system for construction companies and construction projects.

Keywords: corruption, construction industry, integrity, lean construction

Procedia PDF Downloads 382

Authors: Ibrahim Mahamid, A. Al-Ghonamy, M. Aichouni

Abstract:

This study is conducted to identify causes of cost deviations in public construction projects in Saudi Arabia from contractors’ perspective. 41 factors that might affect cost estimating accuracy were identified through literature review and discussion with some construction experts. The factors were tabulated in a questionnaire form and a field survey included 51 contractors from the Northern Province of Saudi Arabia was performed. The results show that the top five important causes are: wrong estimation method, long period between design and time of implementation, cost of labor, cost of machinary and absence of construction-cost data.

Keywords: cost deviation, public construction, cost estimating, Saudi Arabia, contractors

Procedia PDF Downloads 481

Authors: E. H. N. Gashti, M. Zarrini, M. Irannezhad, J. R. Langroudi

Abstract:

Using ETABS software, this study analyzed 23 buildings to evaluate effects of mistakes during construction phase on buildings structural behavior. For modelling, two different loadings were assumed: 1) design loading and 2) loading due to the effects of mistakes in construction phase. Research results determined that considering traditional construction methods for buildings resulted in a significant increase in dead loads and consequently intensified the displacements and base-shears of buildings under seismic loads.

Keywords: reinforced-concrete buildings, construction mistakes, base-shear, displacements, failure

Procedia PDF Downloads 273

Authors: Khodzhaberdi Allaberdiev

Abstract:

Aromaticity, one of the most important concepts in organic chemistry, has attracted considerable interest from both experimentalists and theoreticians. The geometry optimization of p-substituted o-(N-dialkyl)aminomethylphenols, o-DEAMPH XC₆ H₅CH ₂Y (X=p-OCH₃, CH₃, H, F, Cl, Br, COCH₃, COOCH₃, CHO, CN and NO₂, Y=o-N (C₂H₅)₂, o-DEAMPHs have been performed in the gas phase using the B3LYP/6-311+G(d,p) level. Aromaticities of the considered molecules were investigated using different indices included geometrical (HOMA and Bird), electronic (FLU, PDI and SA) magnetic (NICS(0), NICS(1) and NICS(1)zz indices. The linear dependencies were obtained between some aromaticity indices. The best correlation is observed between the Bird and PDI indices (R² =0.9240). However, not all types of indices or even different indices within the same type correlate well among each other. Surprisingly, for studied molecules in which geometrical and electronic cannot correctly give the aromaticity of ring, the magnetism based index successfully predicts the aromaticity of systems. 1H NMR spectra of compounds were obtained at B3LYP/6–311+G(d,p) level using the GIAO method. Excellent linear correlation (R²= 0.9996) between values the chemical shift of hydrogen atom obtained experimentally of 1H NMR and calculated using B3LYP/6–311+G(d,p) demonstrates a good assignment of the experimental values chemical shift to the calculated structures of o-DEAMPH. It is found that the best linear correlation with the Hammett substituent constants is observed for the NICS(1)zz index in comparison with the other indices: NICS(1)zz =-21.5552+1,1070 σp- (R²=0.9394). The presence intramolecular hydrogen bond in the studied molecules also revealed changes the aromatic character of substituted o-DEAMPHs. The HOMA index predicted for R=NO2 the reduction in the π-electron delocalization of 3.4% was about double that observed for p-nitrophenol. The influence intramolecular H-bonding on aromaticity of benzene ring in the ground state (S0) are described by equations between NICS(1)zz and H-bond energies: experimental, Eₑₓₚ, predicted IR spectroscopical, Eν and topological, EQTAIM with correlation coefficients R² =0.9666, R² =0.9028 and R² =0.8864, respectively. The NICS(1)zz index also correlates with usual descriptors of the hydrogen bond, while the other indices do not give any meaningful results. The influence of the intramolecular H-bonding formation on the aromaticity of some substituted o-DEAMPHs is criteria to consider the multidimensional character of aromaticity. The linear relationships as well as revealed between NICS(1)zz and both pyramidality nitrogen atom, ΣN(C₂H₅)₂ and dihedral angle, φ CAr – CAr -CCH₂ –N, to characterizing out-of-plane properties.These results demonstrated the nonplanar structure of o-DEAMPHs. Finally, when considering dependencies of NICS(1)zz, were excluded data for R=H, because the NICS(1) and NICS(1)zz values are the most negative for unsubstituted DEAMPH, indicating its highest aromaticity; that was not the case for NICS(0) index.

Keywords: aminomethylphenols, DFT, aromaticity, correlations

Procedia PDF Downloads 184

Authors: Hyeon-Seung Kim, Bit-Na Cho, Tae-Woon Jeong, Soo-Young Yoon, Leen-Seok Kang

Abstract:

Recently, a construction project has been large in the size and complicated in the site work. The web-cameras are used to manage the construction site of such a large construction project. They can be used for monitoring the construction schedule as compared to the actual work image of the planned work schedule. Specially, because the 4D CAD system that the construction appearance is continually simulated in a 3D CAD object by work schedule is widely applied to the construction project, the comparison system between the real image of actual work appearance by web-camera and the simulated image of planned work appearance by 3D CAD object can be an intelligent construction schedule management system (ICON). The delayed activities comparing with the planned schedule can be simulated by red color in the ICON as a virtual reality object. This study developed the ICON and it was verified in a real bridge construction project in Korea. To verify the developed system, a web-camera was installed and operated in a case project for a month. Because the angle and zooming of the web-camera can be operated by Internet, a project manager can easily monitor and assume the corrective action.

Keywords: 4D CAD, web-camera, ICON (intelligent construction schedule management system), 3D object image

Procedia PDF Downloads 510

Authors: Josephine Mutwale-Ziko, Nonde Lushinga, Inonge Akakandelwa

Abstract:

The study discusses the effectiveness of health and safety induction practices on construction sites against the background of the Zambian construction industry experience. The research design included the literature review of relevant literature. Questionnaires and interviews were administered to regulatory bodies, health, and safety personnel. Observation was also employed on construction sites to assess the health and safety practices being used. Health and safety in the construction industry are not something to be ignored or overlooked. The construction industry needs to take heed of the serious consequences of inadequate health and safety induction practices. The implications of inadequate health and safety induction procedures included among others threats to profitability, corporate social responsibility and increased turnover of the workforce leading to poor productivity. Adequate health and safety practices can improve the health and wellbeing of employees, reduce financial implications on firms and encourage productivity on construction sites. Despite this, accidents are still prevalent on construction sites in Zambia. The overall result of this research denotes that the implementation of health and safety induction practices is inadequate, as indicated by the negligent and non-adherent attitude to health and safety induction aspects on the sites by most stakeholders on construction sites. Therefore, health and safety induction practices are ineffective as preventive measures for reduction of accidents on construction sites in Zambia.

Keywords: accidents, health and safety, inadequate, induction

Procedia PDF Downloads 456

Authors: Mokhtar Nikgoo

Abstract:

Civil engineering is one of the disciplines that shows the application of science in creating construction and civil engineering. That is, everything that returns to the population of a country, such as dams, airports, roads, bridges, towers, tunnels, telecommunication towers, buildings resistant to earthquakes, floods and fires, power plants and light, cheap and quality materials for construction. And the construction is included in the scope of work of the civil engineer. Civil engineering covers a wide range of tasks. That is, for the construction of buildings, bridges, towers, tunnels, roads, silos, or sewage networks, an efficient civil engineer is needed at the beginning, in addition to complying with the technical and operational aspects, he also works economically. Because being economical is a principle in civil engineering. Is. This field at the undergraduate level has three majors: civil-building, civil-mapping and civil-water.

Keywords: civil engineering, construction, surveying, mapping, pile

Procedia PDF Downloads 87

Authors: Ikumapayi Catherine Mayowa

Abstract:

The well-being of humans on a construction site is critical; abundant manpower had been lost through accidents which kill or make workers physically unfit to carry out construction activities, these, in turn, have multiple effects on the whole economy. Thus, it is necessary to put all safety items and regulations in place before construction activities can commence. This study was carried out in the Ondo state of Nigeria to investigate and analyze the state of health and safety of construction workers in the state. The study was done using first-hand observations, 50 construction project sites were visited in ten major towns of Ondo state, questionnaires were distributed, and the results were analyzed. The result shows that construction workers are being exposed to many construction site hazards due to lack of inadequate safety programs and lack of appropriate safety equipment for workers on site. From the data gotten from each site visited and the statistical analysis, it can be concluded that occurrences of an accident on construction sites depend significantly on the available safety facilities on the sites. The result of the regression statistics shows that the dependence of the frequency of occurrence of an accident on the availability of safety items on the site is 0.0362 which is less than 0.05 maximum significant level allowed. Therefore, a vital way of sustaining our building strategy is given a detail attention to the provision of adequate health and safety items on construction sites which will reduce the occurrence of accident, loss of manpower and death of skilled workers.

Keywords: construction sites, health, safety, welfare

Procedia PDF Downloads 333

Authors: B. M. Arthur-Aidoo, C. O. Aigbavboa, W. D. Thwala

Abstract:

The performance of construction employees cannot be underestimated if the success of construction projects are to be achieved. This is because the construction industry has been characterised as labour oriented sector, which most of its activities being executed by labour. In the construction sector, employees are driven by incentive schemes which perform encourage and motivate workers for higher efficiency and higher output. The construction sector, however, depends mainly on its labour. In view of the sector's high dependency on its employees, that there must be a significant incentive scheme which must be established to act as a stimulus to drive high performance from employees among the various known incentive packages. This study, therefore, seeks to appraise the incentive packages adopted by construction SMEs. To establish reliable findings that will contribute to knowledge, the study utilised an exploratory approach via semi-structured interviews among sampled construction professionals with the requisite expertise on employees' incentive schemes. The study further established that although incentive schemes are classified in various ways and mediums that act as stimuli to encourage high performance among employees, some are more influential and impacts performance than others. Additionally, the study concludes that medical allowance, holiday with pay, free working tools, and training for employees were ranked the most influential incentives that promote high outputs by workers within the construction SME sector.

Keywords: appraisal, construction, employees, incentive, small and medium-sized enterprises, SMEs

Procedia PDF Downloads 143

Authors: Nidhal Mgadmi, Abdelhafidh Othmani

Abstract:

This article examines the causal relationship between stock indices and cryptocurrencies during the current war between Russia and Ukraine. The econometric investigation runs from February 24, 2022, to April 12, 2023, focusing on seven stock market indices (S&P500, DAX, CAC40, Nikkei, TSX, MOEX, and PFTS) and seven cryptocurrencies (Bitcoin, Ethereum, Litcoin, Dash, Ripple, DigiByte and XEM). In this article, we try to understand how investors react to fluctuations in financial assets to seek safe havens in cryptocurrencies. We used dynamic causality to detect a possible causal relationship in the short term and seven models to estimate the long-term relationship between cryptocurrencies and financial assets. The causal relationship between financial market indexes and cryptocurrency coins in the short run indicates that three famous cryptocurrencies (BITCOIN, ETHEREUM, RIPPLE) and the two digital assets with minor popularity (XEM, Digibyte) are impacted by the German, Russian, and Ukrainian stock markets. In the long run, we found a positive and significate effect of the American, Canadian, French, and Ukrainian stock market indexes on Bitcoin. Thus, the stability of the traditional financial markets during the current war period can be explained on the one hand by investors’ fears of an unstable business climate, and on the other hand, by speculators’ sentiment towards new electronic products, which are perceived as hedging instruments and a safe haven in the face of the conflict between Ukraine and Russia.

Keywords: causality, stock indices, cryptocurrency, war, Russia, Ukraine

Procedia PDF Downloads 72

Authors: Emmanuel Donkor

Abstract:

Aim/Purpose – This paper examines the influence of construction workers wages and working conditions on productivity in Ghana. Design/methodology/Approach - The study adopted a quantitative research approach with purposive sampling techniques where data was collected using surveys. The data were analyzed using SPSS software version 20.0, which enables the findings of the study to be examined under thematic areas.Findings: - The study revealed that good wages and working condition of workers have a positive correlation on productivity in the construction industry. Increase and improved wages and working conditions can results in higher productivity in the construction industry.Originality/value - This paper is exceptional in the sense that, it does examine the influence of construction workers wages and working conditions on productivity in Ghana. Social value/implications - The paper concludes that workers’ wages and their conditions have a high influence on productivity. It is then recommended that government should train, educate, give good wages to workers and improve on their working condition, give incentives and reduce tax importation on building or construction materials to aid in good productivity of construction firms.

Keywords: construction firms, construction industry, productivity, workers’ wages, working conditions

Procedia PDF Downloads 140

Authors: J. Tamosaitiene

Abstract:

The article focuses on the identification and classification of key risk management criteria that represent the most important sustainability aspects of the construction industry. The construction sector is one of the most important sectors in Lithuania. Nowadays, the assessment of the risk level of a construction project is especially important for the quality of construction projects, the growth of enterprises and the sector. To establish the most important criteria for successful growth of the sector, a questionnaire for experts was developed. The analytic hierarchy process (AHP), the expert judgement method and other multicriteria decision making (MCDM) methods were used to develop the hybrid model. The results were used to develop an integrated knowledge system for the measurement of a risk level particular to construction projects. The article presents a practical case that details the developed system, sustainable aspects, and risk assessment.

Keywords: risk, system, model, construction

Procedia PDF Downloads 171

Authors: Abdullah Alsehaimi

Abstract:

Over decades, there have been many studies of delay in construction, and this type of study continues to be popular in construction management research. A synthesis and critical evaluation of delay studies in developing countries reveals that poor project management is cited as one of the main causes of delay. However, despite such consensus, most of the previous studies fall short in providing clear recommendations demonstrating how project management practice could be improved. Moreover, the majority of recommendations are general and not devoted to solving the difficulties associated with particular delay causes. This paper aims to demonstrate that the root cause of this state of affairs is that typical research into delay tends to be descriptive and explanatory, making it inadequate for solving persistent managerial problems in construction. It is contended that many problems in construction could be mitigated via alternative research approaches, i.e. action and constructive research. Such prescriptive research methods can assist in the development and implementation of innovative tools tackling managerial problems of construction, including that of delay. In so doing, those methods will better connect research and practice, and thus strengthen the relevance of academic construction management.

Keywords: construction delay, action research, constructive research, industrial engineering

Procedia PDF Downloads 429

Authors: Soner Guler, Fuat Korkut

Abstract:

Recently, the using of lightweights concretes in construction sector is rapidly increasing all over the world. Faster construction, low density and thermal transmitting coefficient and high fire resistance are the remarkable characteristics of the lightweight concretes. Lightweight concrete can be described as a type of concrete which enhance the volume of the mixture while giving additional advantages such as to reduce the dead weight of the structures. It is lighter than the conventional concrete. The use of lightweight concrete has been widely spread across countries such as USA, United Kingdom, and Sweden. In this study, the necessity of the using of lightweights concretes in the construction sector is emphasized and evaluated briefly for the architectures and civil engineers.

Keywords: lightweights concretes, low density, low thermal coefficient, construction sector

Procedia PDF Downloads 513

Authors: Xi Zuo

Abstract:

Against the background of the aging population and changing family structure in China, community canteens have become an important vehicle for community-based home care services and a new space for social interaction. In this paper, we review past studies and the actual construction situation in China, firstly sort out the social interaction of the elderly and the types of places, and on this basis, we find that there is an obvious disconnection between the current construction and the academic research, and the contradiction between social benefit and cost-effectiveness, and therefore we put forward the relevant construction planning and thinking, in order to provide a disciplinary basis and academic support for the construction of community canteens and the construction of elderly-friendly cities. In order to provide disciplinary basis and academic support for the construction of community canteens and the construction of senior-friendly cities.

Keywords: urban and rural planning, community canteens, elderly people, senior-friendly

Procedia PDF Downloads 63

Authors: Nima Amani, Ali Salehi Dastjerdi, Fatemeh Ahmadi, Ardalan Sabamehr

Abstract:

The cost overrun of the construction projects has always been one of the main problems of the construction companies caused by the risky nature of the construction projects. Therefore, today, the application of risk management is inevitable. Although in theory, the issue of risk management is divided into the opportunities and threats management, in practice, most of the projects have been focused on the threats management. However, considering the opportunities management and applying the opportunities-response strategies can lead to the improved profitability of the construction projects of the companies. In this paper, a new technique is developed to identify the opportunities in the construction projects using an improved protocol and propose the appropriate opportunities-response strategies to the construction companies to provide them with higher profitability. To evaluate the effectiveness of the protocol for selecting the most appropriate strategies in ‎response to the opportunities and threats, two projects from a construction company in Iran were ‎studied. Both projects selected were in mid-range in terms of size and similar in terms of time, ‎run time and costs. Finally, the output indicates that using the proposed opportunities-response strategies show that the company's profitability in the future can be increased approximately for similar projects.

Keywords: opportunities management, risk-response strategy, opportunity-response strategy, productivity, risk management

Procedia PDF Downloads 234

Authors: Hongyu Ye, Hong Zhang, Minjie Sun, Hongfang Xu

Abstract:

In the context of China's promotion of smart construction and building industrialization, there is a need for evaluation standards for the development of building industrialization based on assembly-type construction. However, the evaluation of smart construction remains a challenge in the industry's development process. This paper addresses this issue by proposing a calculation and evaluation method for the smartization rate of concrete structure building construction. The study focuses on examining the factors of smart equipment application and their impact on costs throughout the process of smart construction design, production, transfer, and construction. Based on this analysis, the paper presents an evaluation method for the smartization rate based on components. Furthermore, it introduces calculation methods for assessing the smartization rate of buildings. The paper also suggests a rapid calculation method for determining the smartization rate using Building Information Modeling (BIM) and information expression technology. The proposed research provides a foundation for the swift calculation of the smartization rate based on BIM and information technology. Ultimately, it aims to promote the development of smart construction and the construction of high-quality buildings in China.

Keywords: building industrialization, high quality building, smart construction, smartization rate, component

Procedia PDF Downloads 76

Authors: A. Khelifi, M. Al Kaabi, B. Al Rawashdeh

Abstract:

The infrastructure is one of the most important pillars of the UAE, where it spends millions of dollars for investments in the construction sectors. The research done by Kuwait Finance House (KFH) Research showed clearly that the UAE investments in the construction sectors have exceeded 30 billion dollars in 2013. There are many construction companies in the UAE and each one of them is taking the responsibilities to build different infrastructures. The large scale construction projects consist of multi human activities which can affect the efficiency and productivity of the running projects. The Construction Administration System is developed to increase the efficiency and productivity at the construction sites. It runs on two platforms: web server and mobile phone and supports two main users: mobile user and institution employee. With Construction Administration Mobile Application the user can manage and control several projects, create several reports and send these reports in Portable Document Format (PDF) formats through emails, view the physical location of each project, capturing and save photos. An institution employee can use the system to view all existing workers and projects, send emails and view the progress of each project.

Keywords: construction sites, management, mobile application, Portable Document Format (PDF)

Procedia PDF Downloads 376

Authors: H. Tavakoli, S. S. Mohtasebi, R. Alimardani, R. Gebbers

Abstract:

Nitrogen (N) is one of the most important agricultural inputs affecting crop growth, yield and quality in rain-fed cereal production. N demand of crops varies spatially across fields due to spatial differences in soil conditions. In addition, the response of a crop to the fertilizer applications is heavily reliant on plant available water. Matching N supply to water availability is thus essential to achieve an optimal crop response. The objective of this study was to determine effect of drought stress on estimation of nitrogen status of winter wheat by some vegetation indices. During the 2012 growing season, a field experiment was conducted at the Bundessortenamt (German Plant Variety Office) Marquardt experimental station which is located in the village of Marquardt about 5 km northwest of Potsdam, Germany (52°27' N, 12°57' E). The experiment was designed as a randomized split block design with two replications. Treatments consisted of four N fertilization rates (0, 60, 120 and 240 kg N ha-1, in total) and two water regimes (irrigated (Irr) and non-irrigated (NIrr)) in total of 16 plots with dimension of 4.5 × 9.0 m. The indices were calculated using readings of a spectroradiometer made of tec5 components. The main parts were two “Zeiss MMS1 nir enh” diode-array sensors with a nominal rage of 300 to 1150 nm with less than 10 nm resolutions and an effective range of 400 to 1000 nm. The following vegetation indices were calculated: NDVI, GNDVI, SR, MSR, NDRE, RDVI, REIP, SAVI, OSAVI, MSAVI, and PRI. All the experiments were conducted during the growing season in different plant growth stages including: stem elongation (BBCH=32-41), booting stage (BBCH=43), inflorescence emergence, heading (BBCH=56-58), flowering (BBCH=65-69), and development of fruit (BBCH=71). According to the results obtained, among the indices, NDRE and REIP were less affected by drought stress and can provide reliable wheat nitrogen status information, regardless of water status of the plant. They also showed strong relations with nitrogen status of winter wheat.

Keywords: nitrogen status, drought stress, vegetation indices, precision agriculture

Procedia PDF Downloads 323

Authors: Ismaila Oladunni Muhammed, Adegbenga Raphael Ashiru

Abstract:

Construction industry has been attributed to be the engine growth of Nigerian economic and infrastructural development. It promotes infrastructural development and grows an average output of Nigerian Gross Domestic Profit. However, from this great prospect, yearly reports show that consistent accidents on construction sites in Zamfara State has affected a substantial number of workers as they become temporarily or permanently disabled, thereby making many construction sites a death trap. This posed a great threat to the industry’s sustainability, de- motivate workers from working in the industry, and further have negative impact on the economy as well. It is as a result of high construction site accident currently experiencing in Zamfara state that this research was carried out to appraise the sustainability of health and safety of construction workers on sites. The proper practice and compliance to Construction Health and safety laws are very vital to the output and growth of Zamfara State construction sector. However, a quantitative approach was adopted to justify the aforesaid statement which will provide a broader understanding of the study. Descriptive statistical analysis was obtained through Statistical Package for the Social Sciences (SPSS Version 20). Furthermore, the findings from the research highlighted that the performance and output of construction workers on construction sites depends on the proper practice of health and safety. The research findings also recommended ways to enhance employers and employee’s compliance with existing laws guiding health and safety on Zamfara State construction sites. Nevertheless, the purpose of the paper is to appraise the sustainability of Health and Safety on Zamfara State construction sites. This study further provided thorough information for resolving challenges of construction sites accidents to improve construction firm productivity and also ensured construction worker’s safety on site.

Keywords: construction industry, health and safety regulations, causes of accident, construction safety practices

Procedia PDF Downloads 214

Authors: Hina Munir Abbasi

Abstract:

The current paper examines the relationship and diversification ability of Islamic stock indices /conventional stocks indices and Real Estate Investment Trust (REITs).To represent conditional dependency between stocks and REITs in a more realistic way, new modeling technique, time-varying copula with switching dependence is used. It represents reliance structure more accurately and realistically than a single copula regime as dependence may alter between positive and negative correlation regimes with time. The fluctuating behavior of markets has significant impact on economic variables; especially the downward trend during crisis. Overall addition of Real Estate Investment Trust in stocks portfolio reduces risks and provide better diversification benefit. Results varied depending upon the circumstances of the country. REITs provides better diversification benefits for Islamic Stocks, when both markets are bearish and can provide hedging benefit for conventional stocks portfolio.

Keywords: conventional stocks, real estate investment trust, copula, diversification, risk spillover, safe heaven

Procedia PDF Downloads 89

Authors: Abdul-Monim Batiha, Manar AlAzzam, Mohammed ALBashtawy, Loai Tawalbeh, Ahmad Tubaishat, Fadwa N. Alhalaiqa

Abstract:

Background: Obesity is the major modifiable risk factor for many chronic illnesses especially high blood pressure. Objectives: To evaluate the relationship between anthropometric indices and high blood pressure, and which one was most strongly correlated with high blood pressure in Jordanian population. Methods: A cross-sectional study was conducted with a total 622 students and workers from three Jordanian universities. Results: Nearly half of the participant are overweight (34.7%) and obese (15.4%) and hypertension was detected among 138 (22.2%) of the participants. Linear correlation was significant (p<0.01) between both systolic blood pressure and diastolic blood pressure for all anthropometric indices, except for A body shape index and diastolic blood pressure was significant at p< 0.05. Stepwise multiple linear regression analysis was used to assess the influence of age and anthropometric measurements. Conclusions: The waist circumference was the only independent predictor of hypertension, showing that this simple measurement may be an importance marker of high blood pressure in Jordanian population.

Keywords: anthropometric indices, Jordan, blood pressure, cross-sectional study, obesity, hypertension, waist circumference

Procedia PDF Downloads 291

Authors: Maryam Sadeghi, Claude Bazin, Daniel Hodouin, Laura Perez Barnuevo

Abstract:

The performance of a separation process is usually evaluated using performance indices calculated from elemental assays readily available from the chemical analysis laboratory. However, the separation process performance is essentially related to the properties of the minerals that carry the elements and not those of the elements. Since elements or metals can be carried by valuable and gangue minerals in the ore and that each mineral responds differently to a mineral processing method, the use of only elemental assays could lead to erroneous or uncertain conclusions on the process performance. This paper discusses the advantages of using performance indices calculated from minerals content, such as minerals recovery, for process performance assessments. A method is presented that uses elemental assays to estimate the minerals content of the solids in various process streams. The method combines the stoichiometric composition of the minerals and constraints of mass conservation for the minerals through the concentration process to estimate the minerals content from elemental assays. The advantage of assessing a concentration process using mineral based performance indices is illustrated for an iron ore concentration circuit.

Keywords: data reconciliation, iron ore concentration, mineral composition, process performance assessment

Procedia PDF Downloads 224

Authors: Yassir AbdelRazig

Abstract:

Evolutionary optimization methods such as genetic algorithms have been used extensively for the construction site layout problem. More recently, ant colony optimization algorithms, which are evolutionary methods based on the foraging behavior of ants, have been successfully applied to benchmark combinatorial optimization problems. This paper proposes a formulation of the site layout problem in terms of a sequencing problem that is suitable for solution using an ant colony optimization algorithm. In the construction industry, site layout is a very important planning problem. The objective of site layout is to position temporary facilities both geographically and at the correct time such that the construction work can be performed satisfactorily with minimal costs and improved safety and working environment. During the last decade, evolutionary methods such as genetic algorithms have been used extensively for the construction site layout problem. This paper proposes an ant colony optimization model for construction site layout. A simple case study for a highway project is utilized to illustrate the application of the model.

Keywords: ant colony, construction site layout, optimization, genetic algorithms

Procedia PDF Downloads 385

Authors: G. Chakhaia, S. Gogilava, L. Tsulukidze, Z. Laoshvili, I. Khubulava, S. Bosikashvili, T. Gugushvili

Abstract:

The work reviewed and evaluated various genesis debris flow phenomena recently formatted in the Mletiskhevi, accordingly it revealed necessity of treatment modern debris flow against measures. Based on this, it is proposed the debris flow against truncated semi cone shape construction, which elements are contained in the car’s secondary tires. its constituent elements (sections), due to the possibilities of amortization and geometric shapes is effective and sustainable towards debris flow hitting force. The construction is economical, because after crossing the debris flows in the river bed, the riverbed is not cleanable, also the elements of the building are resource saving. For assessment of influence of cohesive debris flow at the construction and evaluation of the construction effectiveness have been implemented calculation in the specific assumptions with approved methodology. According to the calculation, it was established that after passing debris flow in the debris flow construction (in 3 row case) its hitting force reduces 3 times, that causes reduce of debris flow speed and kinetic energy, as well as sedimentation on a certain section of water drain in the lower part of the construction. Based on the analysis and report on the debris flow against construction, it can be said that construction is effective, inexpensive, technically relatively easy-to-reach measure, that’s why its implementation is prospective.

Keywords: construction, debris flow, sections, theoretical calculation

Procedia PDF Downloads 196

Authors: Uttam Neupane, Narendra Budha, Subash Kumar Bhattarai

Abstract:

Material management is an essential part in construction project management. There are a number of material management problems in the Nepalese construction industry, which contribute to an inefficient material management system. Ineffective material management can cause waste of time and money thus increasing the problem of time and cost overrun. An assessment of material management system with gap and solution was carried out on 20 construction projects implemented by the Federal Level Project Implementation Unit (FPIU); Kaski district of Nepal. To improve the material management process, the respondents have provided possible solutions to overcome the gaps seen in the current material management process. The possible solutions are preparation of material schedule in line with the construction schedule for material requirement planning, verifications of material and locating of source, purchasing of the required material in advance before commencement of work, classifying the materials, and managing the inventory based on their usage value and eliminating and reduction in wastages during the overall material management process.

Keywords: material management, construction site, inventory, construction project

Procedia PDF Downloads 76

Authors: Hadi Rouhi Belvirdi

Abstract:

The construction of underground structures using the traditional method, which begins with excavation and the implementation of the foundation of the underground structure, continues with the construction of the main structure from the ground up, and concludes with the completion of the final ceiling, is known as the Bottom-Up Method. In contrast to this method, there is an advanced technique called the Top-Down Method, which has practically replaced the traditional construction method in large projects in industrialized countries in recent years. Unlike the traditional approach, this method starts with the construction of surrounding walls, columns, and the final ceiling and is completed with the excavation and construction of the foundation of the underground structure. Some of the most significant advantages of this method include the elimination or minimization of formwork surfaces, the removal of temporary bracing during excavation, the creation of some traffic facilities during the construction of the structure, and the possibility of using it in limited and high-traffic urban spaces. Despite these numerous advantages, unfortunately, there is still insufficient awareness of this method in our country, to the extent that it can be confidently stated that most stakeholders in the construction industry are unaware of the existence of such a construction method. However, it can be utilized as a very important execution option alongside other conventional methods in the construction of underground structures. Therefore, due to the extensive practical capabilities of this method, this article aims to present a methodology for constructing underground structures based on the aforementioned advanced method to the scientific community of the country, examine the advantages and limitations of this method and their impacts on time and costs, and discuss its application in urban spaces. Finally, some underground structures executed in the Ahvaz urban rail, which are being implemented using this advanced method to the best of our best knowledge, will be introduced.

Keywords: top-down method, bottom-up method, underground structure, construction method

Procedia PDF Downloads 19