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Online spiral pipe manufacturing is one of the most common processes for producing water and gas transmission pipes. Weld quality and pipe circumstances are the most important qualitative characteristics of these pipes determining the overall cost of production. The purpose of this paper is describing how to implement Six Sigma on the production of spiral welded pipes with a real case study.

First, the capability of the pipe production process has been performed by using the defects per million opportunities to allow for comparison and analysis of the project effectiveness. Then, the variation pattern of this index, after an improvement project, has been investigated. Finally, Taguchi's loss functions are used to evaluate the effectiveness of these projects.

The results represent a significant improvement in the production process and a reduction in production costs regarding both weld quality and pipe circumstances. Due to the successful implementation of Six Sigma project in welding and pipe quality improvement, the Define, Measure, Analyze, Improve and Control (DMAIC) method can be used effectively in defining weld and pipe quality.

In this proposed work, for the first time, research on the implementation of Six Sigma in the pipeline and welding industries on two online spiral production machines has been investigated. The DMAIC method has been used for the first time to improve the dimensional quality and weld quality of spiral pipes.

This paper aims to present the design and implementation of VirSense, a novel six-DOF haptic interface system, with an emphasis on its gravity compensation and fixed-base motors.

In this paper, the design and manufacture of the VirSense robot and its comparison with the existing haptic devices are presented. The kinematic analysis of the robot, design of the components, and manufacturing of the robot are explained as well.

The proposed system is employed to generate a Virtual Sense (VirSense) with fixed-base motors and a spring compensation system for counterbalancing the torques generated by the weight of the links. The fixed bases of the motors reduce the system's effective mass and inertia, which is an important factor in haptic interface systems. A novel cabling system is used to transmit the motor torques to the end-effector. The spring-based gravity compensation system causes more reduction in the effective mass and inertia.

This paper provides the details of the VirSense haptic device, its gravity compensation system, and a novel cabling power transmission.

This study aims to identify the main factors affecting export competitiveness and its barriers, focusing on the minerals industry so that a scale is achieved for measuring export competitiveness in this industry.

The research was conducted with a mixed method approach in the minerals industry. Among the active companies involved in this industry, 34 export companies and export management companies were selected and evaluated. In the qualitative phase, 18 experts and managers of the industry were interviewed to identify the factors affecting the export competitiveness of these companies and the barriers ahead of them. In the quantitative phase, a questionnaire was distributed among 412 managers and experts in this industry to categorize the identified factors and to measure the relationships among them. For data analysis in the qualitative phase, theme analysis was used. For the quantitative phase, factor analysis and structural equation modeling were adopted.

In addition to identifying the main components affecting the competitiveness of companies in exporting minerals as well as the main barriers ahead of them, the findings of the current research categorized these components using factor analysis. These components were categorized into factors, such as manufacturing factors, demand conditions, related and supporting industries, structural factors, competitive strategy and governmental supports. Afterward, their impacts on export competitiveness were measured and supported.

Although some studies have been conducted to examine the competitiveness in different industries, no research has been found that has examined and identified the main factors affecting export competitiveness and their impacts in the minerals industry with a mixed quantitative and qualitative approach. The findings of this research may help managers and policymakers, at the industrial and national levels, to reach a scale for assessing the export companies involved in this industry by identifying the most essential factors of export competitiveness of minerals. Furthermore, the findings of this research can act as a model for future researchers to develop a scale for export competitiveness in other industries.

Hardgrove grindability index (HGI) is an important physical parameter used to demonstrate the relative hardness of coal particles. Modeling of HGI based on coal conventional properties is a quite complicated procedure. The paper aims to develop a new accurate model for prediction of HGI that is called optimized evolutionary neural network (OPENN).

The procedure for generation of the proposed OPENN predictive model was performed in two stages. In the first stage, as the high dimensionality involved in the input space, a correlation-based feature selection (CFS) algorithm was used to select the most important influencing variables for HGI prediction. In the second stage, a combination of differential evolution (DE) and biography-based optimization (BBO) algorithms as a global search method were applied to evolve weights of a multi-layer perception neural network.

The proposed OPENN was examined and compared with other typical models using a wide range of Kentucky coal samples. The testing results showed that the accuracy of the proposed OPENN model is significantly better than the other typical models and can be considered as a promising alternative for HGI prediction.

As HGI test is relatively expensive procedure, there is an economical interest on HGI modeling based on coal conventional properties (proximate, ultimate and petrography); the proposed OPENN model to estimate HGI would be a valuable and practical tool for coal industry.

This paper aims to propose a policy prioritization framework in view of a layered scenario building along with key stakeholder analysis and has been applied in a case study to determine the priority of Iran environmental policies at the horizon of 2030. A creative framework that covers future scenarios and allows for a more accurate and intelligent policy assessment and prioritization.

The general environmental policies of the Islamic Republic of Iran are evaluated, and observation policies in social area were identified. Causal layered analysis (CLA) is applied for policy prioritization based on layered probable scenarios and key stakeholder role consideration. The Multiple-criteria decision-making (MCDM) is also used for ranking General Environmental Policies by the technique for order of preference by similarity to ideal solution (TOPSIS).

Four uncertainties were obtained in different layers based on the CLA analysis, resulting in the creation of four main scenario and 16 discrete scenarios. Finally, Iran’s environmental policies were prioritized given the probable scenarios and the centralized policies on the social and political domains. The proposed model will be effective in policy-making in multilateral atmosphere to prioritize policies and alternative macro-strategies.

This paper shows that foresight and especially developed scenarios provide intelligent, efficient and effective planning and policy-making, and in addition to illustrating surrounding changes and probable future imagery, it generates common understanding and inter-subjective knowledge by increasing participation of various officials and stakeholders.

The purpose of this study set out to introduce an alternative framework for explaining the formation of the innovation ecosystem based on the systematic literature review (SLR) and ecosystemic approach.

This paper is an SLR of studies from the year 2008-2018 that investigating startups’ innovation. SLR approach being used exploration, interpretation and communication method, which composed of seven steps as follows exploring topics, searching, organizing, evaluating and expanding, integrating and communicating. The output of this process is 63 documents that applied to synthesize the formation framework.

The systematic review of literature has shown that researchers in recent years have considered some entities such as incubators, financials suppliers, accelerators, universities and companies in relation to the startup innovations, which are described in this paper as key actors. The study of the relationship between these actors in the documents led to the identification of interactional necessities, including structures, infrastructures and networks. Finally, the processes studied in the literature were classified into three types of mechanisms, namely, the genesis, growth and development of startups innovations.

The SLR approach is subject to limitations because some poor explanations amongst previous researchers may be repeated and reinforced. Also, in the protocol adopted in this paper, documents are limited in English.

The introduced frammework can be useful in identifying and understanding the requirements of startups and creating effective policies for their innovation development.

This paper reviews, summarizes and integrates the growing and scattered literature of the innovation ecosystem of the startups and delivers new facts for the future development of this field.

The purpose of this paper is to review the risk categories which are predominant in international projects and to rank them according to their effect on project success.

A literature survey of peer-reviewed journal articles, survey reports and books on project management is used as the research methodology. One among the various multi-criteria decision making methods named as Technique for Order Preference by Similarity to the Ideal Solution (TOPSIS) has been used to rank the risk categories according to their importance. The data for TOPSIS were collected through questionnaire as the research instrument.

The findings derived from evaluation of the publications led to the identification of eight different types of risk categories associated with international projects. The TOPSIS method resulted into political risks, technical risks and design-related risks as the top three risk categories in international projects. Contractual and legal risks and fraudulent practices-related risks are relatively low-ranked risk category.

The findings will be useful in successful implementation of international projects as the knowledge of risk categories and their ranking will help project manager to plan the risk response strategies. A larger sample size for decision makers and more variety of projects can give more exhaustive risk categories and their ranking.

This paper explores eight different risk categories in international projects. It represents the ranking of risk categories according to their importance in project success. This will be helpful to project managers for developing a general framework for planning the appropriate risk response strategies.

Governments of many countries around the world are encouraging their industries to undertake and successfully complete projects in foreign countries. However, many industries experience failure in projects as they fail to implement the risk management (RM) effectively in international projects. This research work provides the risk categories in international projects and their ranking which can assist in developing strategies to respond the risk appropriately.

This paper uses the TOPSIS method for ranking major types of risk categories in international projects. It might represent new opportunities for rigorous and relevant research that would contribute to an in-depth knowledge of RM methodologies.

Construction professionals are the major contributors to developing a sustainable construction industry, whereas architects, engineers and quantity surveyors are the key construction professionals who must play extraordinary roles in achieving better sustainable construction. Therefore, this study aims to identify the job attributes of key Sri Lankan construction professionals in addressing challenges associated with climate change.

The study adopted a mixed research approach. A literature review and preliminary semi-structured interviews were used to appraise the job roles of architects, engineers and quantity surveyors in addressing challenges associated with climate change. The data collected through the qualitative approach were used in an online questionnaire survey, and the findings were analysed using the relative index method.

The findings highlight that regardless of the knowledge of the professional category on green rating tools, carbon footprint, adaptation of renewable energies for the reduction of energy consumption, building information modelling-related applications and waste management concepts/practices are the foremost job attributes required for the key Sri Lankan construction professionals in addressing challenges associated with climate change.

The results from this study provide a handful of guidance to construction industry professionals, national and international professional institutions, non-governmental organisations and other relevant authorities to address climate change within the built environment by identifying ways for improving the relevant key job attributes of construction industry professionals.

To the best of the authors’ knowledge, this is the first study that explores the job attributes of key Sri Lankan construction professionals in addressing the challenges associated with climate change.