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The selection of the contractor, as a main participant of a construction project, is the most important and challenging decision process for a client. The purpose of this paper is to propose a multi-agent systems (MAS)-based contractor pre-qualification (CP) model for the construction sector in the frame of the tender management system.

The meta-classification and analysis study of the existing literature on CP, contractor selection and criteria weighting issues, which examines the current and important CP criteria, other than price, is introduced structurally. A quantitative survey, which is carried out to estimate initial weightings of the identified criteria, is overviewed. MAS are used to model the pre-qualification process and workflows are shown in Petri nets formalism. A user-friendly prototype program is created in order to simulate the tendering process. In addition, a real case regarding the construction work in Turkey is analyzed.

There is a lack of non-human-driven solutions and automation in CP and in the selection problem. The proposed model simulates the pre-qualification process and provides consistent results.

The meta-classification study consists of only peer-reviewed papers between 1992 and 2013 and the quantitative survey initiates the perspectives of the actors of Turkish construction sector. Only the traditional project delivery method is selected for the proposed model, that is other delivery methods such as design/build, project management, etc., are not considered. Open, selective limited and negotiated tendering processes are examined in the study and the direct supply is not considered in the scope.

The implications will help to provide an objective CP and selection process and to prevent the delays, costs and other troubles, which are caused by the false selection of a contractor.

Automation and simulation in the pre-qualification and the selection of the contractor with a non-human-driven intelligent solution ease the decision processes of clients in terms of cost, time and quality.

This study aims to identify the trends that have changed in the field of construction management over the last 20 years.

In this study, 3,335 journal articles published in the years 2000–2020 were collected from the Web of Science database in construction management. The authors applied bibliometric analysis first and then detected topics with the latent Dirichlet allocation (LDA) topic detection method.

In this context, 20 clusters from cluster analysis were found and the topics were extracted in clusters with the LDA topic detection method. The results show “building information modeling” and “information management” are the most studied subjects, even though they have emerged in the last 15 years “building information modeling,” “information management,” “scheduling and cost optimization,” “lean construction,” “agile approach” and “megaprojects” are the trend topics in the construction management literature.

This study uses bibliometric analysis. The authors accept that the co-citation and co-authorship relationship in the data is ethical. They accept that honorary authorship, self-citation or honorary citation do not change the pattern of the construction management research domain.

There has been no study conducted in the last 20 years to examine research trends in construction management. Although bibliometric analysis, systematic literature reviews and text mining methods are used separately as a methodology for extracting research trends, no study has used enhanced bibliometric analysis and the LDA topic detection text mining method.

Integrated project delivery (IPD) and building information modeling (BIM) has begun to be used in real estate development projects over the past decade to improve collaboration, communication and efficiency. However, the use of BIM and IPD in projects does not always imply that the information is well used and managed. This study aims to explain how information management should be carried out in BIM and IPD projects, what activities should be managed by the information manager and which stakeholder should play this role and why?

This study provides a framework on the subject by conducting a comprehensive systematic review in the field of real estate development, BIM, IPD and information management. In this context, the Web of Science and Scopus databases have been systematically reviewed, n = 45 out of a total of n = 1,356 articles and additionally, the BIM documents and standards prepared by public institutions and organizations and industry reports have been examined in detail.

The framework for information management roles was established by reviewing the literature. According to this framework, information management activities of information managers are listed in the table that covers all phases of real estate development. The owner should undertake this role as it is the entity that oversees the built asset from planning to the management of that facility.

In terms of acquiring information management roles, there is no research on BIM and IPD projects and who will take over this role. This study desired to close this gap in the literature.

The aim of this paper is to analyze and compare the performance of the construction sector in Turkey and selected European Union (EU) countries using input‐output (IO) tables for the years 1998 and 2002.

IO tables are used to analyze and compare the construction sector. First the input‐output analysis and the construction sector are briefly introduced. Then, the data and methodology are specified. A set of indicators obtained from the data is used for the comparative analysis.

The construction sector of the selected 13 countries is examined in terms of Gross National Product (GNP) and National Income (NI) shares; direct and total construction backward and forward linkage indicators and direct and total construction inputs from manufacturing and services reflecting the technologies used in construction. The key findings are pointed out in the conclusion.

The lack of data from Turkey relating to recent years and incompatibility of new and old data limit this study's scope to the two years.

The concept of using IO analysis for comparing the construction sector has been around for a considerable period of time. This paper has an importance for comparing the construction sector in Turkey and some selected EU countries, being the first study in that field in Turkey, and is therefore of direct importance for the Turkish construction sector.

The research project called “Designing a building material relational database management system for Turkish construction sector”, aims to join “supply side” and “demand side” in the same environment that works on the subject of building material information in the Turkish construction sector. The paper aims to discuss the project findings.

Data were gathered from the information supplied and demanded from the points of sources, levels and frequency of updating by the help of the questionnaires conducted. The data gathered were integrated into the pre‐construction stage and used in the analysis of the process as to how this information was used by the “demand side” for building material information. IDEF‐0, a structured methodology for functional process analysis, is used to figure out building material evaluation and selection processes in the pre‐construction stage.

Material evaluation and selection process for the pre‐construction stage is figured out. Behaviors and requirements of demand‐side and supply‐side in building material information is studied. Difficulties in supplying and presenting building material information in Turkey are evaluated.

Although the subject of the paper is well‐known, Turkish practices and problems are evaluated, and an alternative model is suggested for the Turkish construction sector.

The objectives of this paper are to discuss the constraints stemming from the unstructured nature of the cost estimation practice in Turkey and introduce a generic computer aided building cost estimation model based on a cost significant technique for Turkish construction sector public projects in its detailed design phase.

The research design was based on the simplified version of the bill of quantities method and a cost significant estimating model works on a cost database was suggested to overcome the problems. Underlying principles and basic steps of cost estimation based on cost significant work packages was explained by means of manual calculations.

In order to automate the manual building cost estimation process, the software based on cost significant work packages was developed.

The software is currently in the testing phase and is being used for educational purposes. Making use of both public sector and current market prices in the cost estimation process, increasing number of projects stored in the database for more accurate results, estimating costs of different types of projects and calculating the cost significant value factor more precisely by using statistical techniques, those being employed by global cost models are suggested for future research.

As the number of the similar projects in database is increased, the accuracy of the cost estimation is also increased.

Estimators and graduate students can use the software to estimate building cost of public housing projects in its detailed design phase.

The purpose of this paper is to develop an analytical approach for workload measurement based on the task times and the changing task priorities of en route air traffic controllers (EATC).

A model called Total Airspace Workload Measurement Model was developed to measure EATC workload. Turkish airspace was chosen for practical application of the model. A survey was conducted of EATC to calculate the weighting coefficients and times of different tasks defined in the model. The survey results were analyzed with SPSS 15.0. The real traffic data of Turkish airspace for two peak hours period in heavy traffic covering August 2007 was provided by the General Directorate of Turkish airports. Geomedia 6.0 was employed for the visualization of the real traffic data.

The total airspace workload during two peak hours of traffic, estimated reference sector capacity and the number of operational sector were defined and calculated to analyze the distribution of workload among sectors.

This study can be used for en route sector design such as decision of the number of operational sectors and planning of sectors capacity in the strategic level. Air traffic control service providers can also refer to this study for human resources and equipment planning.

A number of parameters and variables were defined and included in the model by taking into consideration the different service types provided by EATC. All parameters and variables were identified with the task times of the controller. This analytical approach can be applied to those particular airspaces which have different characteristics.

Technological developments are having an impact on the construction sector and are creating a paradigm shift in project delivery methods. Traditional project delivery systems are inadequate in current project development processes. A more integrated project delivery system and the establishment of contractual and financial structures are needed. The purpose of this study is to incorporate integrated project delivery and real estate certificate concepts and propose a model for real estate development.

As a methodology, both integrated project delivery and real estate certificate concepts are reviewed individually, and a case to real estate certificate in Turkey is examined.

A real estate certificate is a new method for financing the development process. The system covers the financial dimension of the integrated project delivery system. When these two concepts are combined, they provide an alternative to the real estate development process.

This study is a preliminary study and lays the foundation for future studies.

In theory, both concepts have many advantages, in practice, it is essential to create the necessary legal basis for these advantages to be valid. As this process requires significant planning and contract management, the proposed model must be properly designed at the start of the project.

This study proposes a new model for real estate development by combining integrated project delivery and real estate certificate concepts.