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Differential search algorithm (DSA) is a new optimization, meta-heuristic algorithm. It simulates the Brownian-like, random-walk movement of an organism by migrating to a better position. The purpose of this paper is to analyze the performance analysis of DSA into two key parts: six random number generators (RNGs) and Benchmark functions (BMF) from IEEE World Congress on Evolutionary Computation (CEC, 2015). Noting that this study took problem dimensionality and maximum function evaluation (MFE) into account, various configurations were executed to check the parameters’ influence. Shifted rotated Rastrigin’s functions provided the best outcomes for the majority of RNGs, and minimum dimensionality offered the best average. Among almost all BMFs studied, Weibull and Beta RNGs concluded with the best and worst averages, respectively. In sum, 50,000 MFE provided the best results with almost RNGs and BMFs.

DSA was tested under six randomizers (Bernoulli, Beta, Binomial, Chisquare, Rayleigh, Weibull), two unimodal functions (rotated high conditioned elliptic function, rotated cigar function), three simple multi-modal functions (shifted rotated Ackley’s, shifted rotated Rastrigin’s, shifted rotated Schwefel’s functions) and three hybrid Functions (Hybrid Function 1 (n=3), Hybrid Function 2 (n=4,and Hybrid Function 3 (n=5)) at four problem dimensionalities (10D, 30D, 50D and 100D). According to the protocol of the CEC (2015) testbed, the stopping criteria are the MFEs, which are set to 10,000, 50,000 and 100,000. All algorithms mentioned were implemented on PC running Windows 8.1, i5 CPU at 1.60 GHz, 2.29 GHz and a 64-bit operating system.

The authors concluded the results based on RNGs as follows: F3 gave the best average results with Bernoulli, whereas F4 resulted in the best outcomes with all other RNGs; minimum and maximum dimensionality offered the best and worst averages, respectively; and Bernoulli and Binomial RNGs retained the best and worst averages, respectively, when all other parameters were fixed. In addition, the authors’ results concluded, based on BMFs: Weibull and Beta RNGs produced the best and worst averages with most BMFs; shifted and rotated Rastrigin’s function and Hybrid Function 2 gave rise to the best and worst averages. In both parts, 50,000 MFEs offered the best average results with most RNGs and BMFs.

Being aware of the advantages and drawbacks of DS enlarges knowledge about the class in which differential evolution belongs. Application of that knowledge, to specific problems, ensures that the possible improvements are not randomly applied. Strengths and weaknesses influenced by the characteristics of the problem being solved (e.g. linearity, dimensionality) and by the internal approaches being used (e.g. stop criteria, parameter control settings, initialization procedure) are not studied in detail. In-depth study of performance under various conditions is a “must” if one desires to efficiently apply DS algorithms to help solve specific problems. In this work, all the functions were chosen from the 2015 IEEE World Congress on Evolutionary Computation (CEC, 2015).

The purpose of this paper is to quantify the barriers to the use of integrated project delivery (IPD), as assessed by 115 construction professionals in Malaysia.

Barriers recording highest citation amongst researchers worldwide were collated in the form of a conceptual model. This model was validated via a partial least squares structural equation modelling technique.

Findings advance the body of knowledge on IPD by providing original insights into the nature of key barriers, quantifying the relative importance of each barrier.

Despite the above-mentioned contributions, and before drawing any conclusion, it is prudent to acknowledge limitations, particularly the chosen research approach in focusing on the Malaysian context. Therefore, caution must be exercised in direct application of findings to other contexts; research findings should be seen through the lens of moderatum generalisations (see Payne and Williams, 2005).

Apart from contributions to the body of knowledge, for the world of practice, conditions impacting a transition to IPD are discussed, with a recommendation for change management through a tested mechanism like the European Corporate Sustainability Framework.

Being the first empirical study undertaken to quantify the relationship among the identified barriers and IPD, the present study contributes to the field by addressing the gap in IPD research in Malaysia, as an exemplar of a developing country; it creates knowledge to inform further improvements in project performance through facilitating IPD use. The study also offers insight to construction stakeholders in other developing countries for tackling issues that hinder the adoption of an IPD approach, and it also points to major barriers such that resources for tackling barriers may be allocated properly.

This paper aims to develop a framework for implementing the integrated project delivery (IPD) approach during the design process in architecture design firms (ADFs) in Egypt.

A research methodology consists of literature review, case studies and survey questionnaire was designed to achieve the abovementioned aim. First, literature review was used to identify and categorise the challenges of implementing IPD during the design process. Second, four case studies were analysed to investigate the values delivered to the client or missed due to the use of IPD or traditional procurement approaches, respectively. Finally, a survey questionnaire was carried out with a representative sample of ADFs in Egypt to investigate their perception towards the challenges of IPD implementation in Egypt. Based on the results of the above, the research developed a framework to facilitate the implementation of IPD in ADFs in Egypt.

Through literature review, the research identified 30 challenges that hamper the implementation of IPD in ADFs. These challenges were categorised due to their nature into five groups, namely, integration, cooperation, commitment and trust challenges, knowledge, experience skills and decision-making challenges, cultural challenges, legal and contractual challenges and technical and financial challenges. Results of data analysis showed that “poor communication and spirit of collaboration between project stakeholders” was ranked the highest influential challenge as IPD is based on collaboration and trust between project participants. In addition, “lack of training and motivation in investing for using IPD” was ranked the lowest influential challenge due to the poor attention paid to training in the construction industry. Moreover, despite the benefits of IPD implementations in many countries worldwide, it is not implemented in the Egyptian context. This necessitated taking action towards developing a framework to facilitate IPD implementation in ADFs in Egypt.

The research focussed on ADFs in Egypt.

Adopting the proposed framework developed through this research will help implementing IPD during the design process in ADFs.

The research identified, categorised and analysed the challenges that obstruct the implementation of IPD in ADFs. The research tackled a topic that received scant attention in construction literature in the Middle East generally and Egypt in particular. In addition, this paper presented a framework to facilitate the implementation of IPD during the design process, which represents a synthesis that is novel and creative in thought and adds value to the knowledge in a manner that has not previously occurred.

The purpose of this paper is to explore the extent to which the firm-specific advantages (FSAs) which underlie international expansion have proved resilient for European multinational enterprises (MNEs) operating in a key emerging market – China.

The authors adopt a qualitative, case study approach, using interview data to explore the companies’ FSAs on market entry, how they evolved over time and the strategies adopted to defend them. They undertook 15 in-depth interviews with decision makers in six companies addressing their experience since market entry. To control for sector-level effects, the authors focus on companies in the environmental protection sector.

The authors found examples of significant erosion of the FSAs among the case study companies, which undermined their position on the host market and their long-term competitiveness. The key sources of erosion were limitations in market access, exclusion from local networks and the emergence and upgrading of local competitors, often firms with whom the MNEs had collaborated in the past.

The relatively small number of cases (six) limits the generalisability of the findings by the authors. However, the authors are convinced that, given that the case companies are generally large and have long experience in China, the conclusions made are well grounded. In addition, there was the high level of coherence in the reported experiences of the interviewees, providing further support for the findings.

The experience of these case study companies highlights that MNEs have difficulty retaining their unique FSAs when faced with rapidly evolving local competition in a key emerging market. Key strategies mobilised included focussing on a sub-sector of the market and localising both the company and their supply chains. The difficulties experiencing by these case study companies in retaining their FSAs underline the need for MNEs in emerging markets to avoid complacency and constantly innovate, but they also raise questions about their capacity to extend their international reach in the long term.

Very few studies have explored the FSAs of firms and how they evolve over time using a case study-based qualitative approach, especially in emerging markets.

Transition is important to all students but especially important to students with intellectual disability who may need additional supports throughout their vertical transitions in education. This chapter discusses different vertical transitions students with intellectual disability face in education, with particular attention to the movement from high school to adult life. Throughout the chapter, research regarding current transition practices and outcomes for students with intellectual disability is discussed as well as evidence-based practices to support students with intellectual disability as they transition to post-school.

Reading fluency, which is critical for developing reading comprehension, is a fundamental skill in both school and life. However, many students with learning and behavioral disabilities are disfluent readers. To improve reading performance for these learners, educators should implement practices shown by reliable research to cause improved reading fluency. In this chapter, following a discussion of reading fluency and its importance, we describe two instructional practices that educators might use to improve students’ reading fluency: colored filters and repeated reading. The research on the colored filters is, at best, inconclusive, whereas the research literature suggests that repeated reading is an effective practice. To bridge the gap between research and practice and improve the reading fluency of students with learning and behavioral disabilities, educators and other stakeholders should prioritize the use of research-based practices (e.g., repeated reading) but avoid practices without clear research support (e.g., colored filters).

The purpose of this paper is to analyze the efficacy of the state policy of Ukraine in the sphere of protection of tangible and intangible cultural heritage, measures of safeguarding cultural property in the event of armed conflict and to assess how and why the state funding of culture has changed.

The proposal is to investigate this by discussing the national and international policy frameworks through case study by using quantitative and qualitative methods to disclose if state cultural policy initiatives promote public interest in cultural issues and how the political events in the country affect the distribution of the state funding of culture.

Ukrainian state cultural policy initiatives appear to be effective in protecting cultural heritage at both central and local levels despite redistribution in the state funding of this sphere. In cooperation with international agencies, Ukraine effectively promotes its intangible cultural heritage properties. Interest of the public in the state cultural policy issues has grown considerably. Problems exist with the protection of Ukrainian cultural sites located in war zones and disputed territories.

These findings demonstrate how the state policies aimed at protecting Ukrainian cultural heritage may be effectively implemented at different levels in cooperation with international agencies; how the political landscape in the country promotes the public interest in cultural policy issues. This case forms an example of steps aimed at protecting cultural properties on disputed territories in cooperation with intermediaries, such as UNESCO.

The proposed IT2FMOVMI model intends to concurrently minimize total cost and warehouse space for the single vendor-retailer, multi-item and a consolidated vendor store. Regarding demand and order quantities with the deterministic and type-1 fuzzy numbers, we have also formulated the classic/crisp MOVMI model and type-1 fuzzy MOVMI (T1FMOVMI) model. The suggested solution technique can solve both crisp MOVMI and T1FMOVMI problems. By finding the optimal ordered quantities and backorder levels, the Pareto-fronts are constructed to form the solution sets for the three models.

A multi-objective vendor managed inventory (MOVMI) is the most recognized marketing and delivery technique for the service provider and the retail in the supply chain in Industry 4.0. Due to the evolving market conditions, the characteristics of the individual product, the delivery period and the manufacturing costs, the demand rate and order quantity of the MOVMI device are highly unpredictable. In such a scenario, a MOVMI system with a deterministic demand rate and order quantity cannot be designed to estimate the highly unforeseen cost of the problem. This paper introduces a novel interval type-2 fuzzy multi-objective vendor managed inventory (IT2FMOVMI) system, which uses interval type-2 fuzzy numbers (IT2FNs) to represent demand rate and order quantities. As the model is an NP-hard, the well-known meta-heuristic algorithm named NSGA-II (Non-dominated sorted genetic algorithm-II) with EKM (Enhanced Karnink-Mendel) algorithm based solution method has been established.

The experimental simulations for the five test problems that demonstrated distinct conditions are considered from the real-datasets of SAPCO company. Experimental study concludes that T1FMOVMI and crisp MOVMI schemes are outclassed by IT2FMOVMI model, offering more accurate Pareto-Fronts and efficiency measurement values.

Using fuzzy sets theory, a significant amount of work has been already done in past decades from various points of views to model the MOVMI. However, this is the very first attempt to introduce type-2 fuzzy modelling for the problem to address the realistic implementation of the imprecise parameters.

The purpose of this article is to present the results obtained from the investigations that have been carried out within the International Successful School Principalship Project (ISSPP) project in the Spanish for social justice.

Twelve case studies have been carried out within the three lines of research proposed by ISSPP: successful principals, underperforming principals and principal leadership identity. All but one school were in challenging contexts. The methodological approach followed is based on multiple perspective case studies using a mixture of qualitative methods (interviews, focus groups and observations).

Results show that successful principals not only believe in social justice through simple empathy with the concept of social justice, but also use strategies that combine transformational and instructional leadership processes and manage to reverse the bad situation of their disadvantaged schools, seeking excellence from equity. The leadership identity of successful principals is characterized to look to the future with hope, adopting a realistic utopian attitude to interpret their surrounding reality.

From the case studies carried out, valuable information is obtained, which helps to understand the possibilities of implementing the ISSPP successful school leadership model in heterogeneous and disadvantaged context for equity and social justice.

The purpose of this paper is to investigate the performance of chaotic gravitational search algorithm (CGSA) in solving mechanical engineering design frameworks including welded beam design (WBD), compression spring design (CSD) and pressure vessel design (PVD).

In this study, ten chaotic maps were combined with gravitational constant to increase the exploitation power of gravitational search algorithm (GSA). Also, CGSA has been used for maintaining the adaptive capability of gravitational constant. Furthermore, chaotic maps were used for overcoming premature convergence and stagnation in local minima problems of standard GSA.

The chaotic maps have shown efficient performance for WBD and PVD problems. Further, they have depicted competitive results for CSD framework. Moreover, the experimental results indicate that CGSA shows efficient performance in terms of convergence speed, cost function minimization, design variable optimization and successful constraint handling as compared to other participating algorithms.

The use of chaotic maps in standard GSA is a new beginning for research in GSA particularly convergence and time complexity analysis. Moreover, CGSA can be used for solving the infinite impulsive response (IIR) parameter tuning and economic load dispatch problems in electrical sciences.

The hybridization of chaotic maps and evolutionary algorithms for solving practical engineering problems is an emerging topic in metaheuristics. In the literature, it can be seen that researchers have used some chaotic maps such as a logistic map, Gauss map and a sinusoidal map more rigorously than other maps. However, this work uses ten different chaotic maps for engineering design optimization. In addition, non-parametric statistical test, namely, Wilcoxon rank-sum test, was carried out at 5% significance level to statistically validate the simulation results. Besides, 11 state-of-the-art metaheuristic algorithms were used for comparative analysis of the experimental results to further raise the authenticity of the experimental setup.