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The purpose of this paper is to propose a novel concept of model prediction control (MPC) parameter optimization method, which is based on pigeon-inspired optimization (PIO) algorithm, with the objective of optimizing the unmanned air vehicles (UAVs) controller design progress.

The PIO algorithm is proposed for parameter optimization in MPC, which provides a new method to get the optimal parameter.

The PIO algorithm is a new swarm optimization method, which consists of two operators, so it can be better adapted for the optimal problems. The comparative consequences results with the particle swarm optimization (PSO) demonstrate the effectiveness of the PIO algorithm, and the superiority for global search is also verified in various cases.

PIO algorithm can be easily applied to practice and help the parameter optimization of the MPC.

In this paper, we first present the concept of using the PIO algorithm for parameter optimization in MPC so as to achieve the global best optimization. By using the PIO algorithm, the choice of the parameter could be easier and more effective. The authors also applied the algorithm to the designing of the MPC controller to optimize the response of the pitch rate of UAV.

Presents over sixty abstracts summarising the 1999 Employment Research Unit annual conference held at the University of Cardiff. Explores the multiple impacts of globalization on work and employment in contemporary organizations. Covers the human resource management implications of organizational responses to globalization. Examines the theoretical, methodological, empirical and comparative issues pertaining to competitiveness and the management of human resources, the impact of organisational strategies and international production on the workplace, the organization of labour markets, human resource development, cultural change in organisations, trade union responses, and trans‐national corporations. Cites many case studies showing how globalization has brought a lot of opportunities together with much change both to the employee and the employer. Considers the threats to existing cultures, structures and systems.

The Chinese construction industry is experiencing a rapid growth these days. Due to the requirements of energy conservation, emission reduction and construction waste management, the development of prefabricated buildings (PBs) has attracted much attention in the Chinese construction industry. However, the development of PBs are still in their infancy in China, which have been negatively impacted by many obstacles. It is of great significance to clarify and analyze these obstacles for the purpose of promoting the development of PBs in China. Due to the wideness and complex features of obstacles, the existing literature exploring the research topic lacks comprehensiveness. The purpose of this paper is to systematically identify and discuss the obstacles that hinder the development of PBs in China.

This paper adopts the method of news report analysis based on the news reports retrieved from China National Knowledge Infrastructure (CNKI) and nine major portals in China. The Term Frequency-Inverse Document Frequency (TF-IDF) method of content analysis was used to rank the obstacles according to their importance.

A total of 79 obstacles to the development of PBs in China are identified, and the 79 obstacles are divided into 8 dimensions. Among the Top 20 obstacles, the government dimension accounted for the highest number of 5, the market and consumer dimension and development organization dimension were 4, Manufacturing Enterprise of Prefabricated Components (PCs) dimension, construction organization dimension and design organization dimension were 2, logistics enterprise dimension was 1, and industry association dimension was 0. Among them, the biggest obstacle is the high transportation costs.

First, data collection may not be very comprehensive. Second, this paper is only based on the obstacles in the development of PBs in China, and the universality of the management conclusions needs to be further strengthened.

The research results help the stakeholders in the Chinese PBs industry to better understand the barriers hindering the industry development in a systemic way, which will help propose appropriate strategies to address these barriers.

This paper clarifies the obstacles of China's PBs and makes an analysis, which is of great value to the development of China's PBs.

This study aims to examine the relationship between corporate governance (CG) and various measures of earnings quality in listed companies on Tehran Stock Exchange (TSE). The theoretical intuition for prediction of any relationship between earnings quality and CG is based on the behavioral theory and the institutional settings in Iran.

This study used the data of 117 listed companies on the TSE for the period from 2005 to 2019. The authors use panel data regression as the main methodology, along with principal component analysis, t-test and rank-sum test.

This study finds that the CG has a positive association with earnings quality. More precisely, better CG mechanisms cause lower earnings smoothness, more predictable and persistent earnings, and higher levels of timeliness, conservatism and value relevance. The relationship between CG and earnings quality is statistically and economically significant for all models.

The findings further the understanding of the role of CG in improving earnings quality in an Islamic and emerging country. First, this study provides evidence on the relation between CG and earnings quality by focusing on the behavioral theory, which suggests that corporate decision-making is not only influenced by formal CG mechanisms, but also by informal CG arrangements. In this case, this study departs from the restrictive theories (specifically, agency theory) that are widely used in past literature. Second, this study constructs an index that fits to corporate context of Iran rather than applying indexes introduced in Anglo-American environments.

The reported mathematical models of gas–liquid flow in single snorkel Rheinstahl–Heraeus (SSRH) are based on the assumption of steady Ar-molten steel flow. The purpose of this paper is to develop a mathematical model to describe the unsteady turbulent flow (CO-Ar-molten steel) with nonequilibrium decarburization reaction.

On the base of the finite volume method, the computational fluid dynamics software CFX is used to predict the unsteady fluid flow, the spatial distributions of CO/argon gas and carbon element. The water model experiment and the industrial experiment are carried out to verify the mathematical models.

A two-way coupling model (T-WCM) based on algebraic slip model is developed to investigate the coupling phenomena. The related results show that T-WCM is more rigorous and accurate than one-way coupling model in predicting carbon content of molten steel. The amount of CO gas, which can enhance turbulent flow and mass transfer, is about three times the argon gas blown into SSRH.

CO gas is the key factor in investigating the transport phenomena. This study fully reveals the truth about the unsteady gas-liquid flow in SSRH. It is necessary to adopt T-WCM based on algebraic slip model to describe the CO-Ar-molten steel flow phenomenon.

The purpose of this paper is to explore the use of inverse local context analysis (ILCA) to obtain data from limited accessible data sources.

The experimental results show that the method the authors proposed can obtain all retrieved documents from the limited accessible data source using the least number of queries.

The experimental results show that the method we proposed can obtain all retrieved documents from the limited accessible data source using the least number of queries.

To the best of the authors’ knowledge, this paper provides the first attempt to gather all the retrieved documents from limited accessible data source, and the efficiency and ease of implementation of the proposed solution make it feasible for practical applications. The method the authors proposed can also benefit the construction of web corpus.

The limited strength of polylactic acid (PLA) hinders its extensive engineering applications. This paper aims to enhance its strength and realize diverse applications.

Here, the continuous fiber reinforced PLA composites are fabricated by a customized fused filament fabrication three-dimensional printer. Uniaxial tensile and three-point flexural tests have been conducted to analyze the reinforcement effect of the proposed composites. To unveil the adhering mechanism of optic fiber (OF) and PLA, post failure analysis including the micro imaging and morphology have been performed. The underlying mechanism is that the axial tensile strength of the OF and the interfacial adhesion between PLA and OF compete to enhance the mechanical properties of the composite.

It is found that 10%–20% enhancement of strength, ductility and toughness due to the incorporation of the continuous OF.

The continuous OFs are put into PLA first time to improve the strength. The fabrication method and process reported here are potentially applied in such engineering applications as aerospace, defense, auto, medicine, etc.

Lattice Boltzmann method (LBM) is employed to explore friction factor of single-phase fluid flow through porous media and the effects of local porous structure including geometry of grains in porous media and specific surface of porous media on two-phase flow dynamic behavior, phase distribution and relative permeability. The paper aims to discuss this issue.

The 3D single-phase LBM model and the 2D multi-component multi-phase Shan-Chen LBM model (S-C model) are developed for fluid flow through porous media. For the solid site, the bounce back scheme is used with non-slip boundary condition.

The predicted friction factor for single-phase fluid flow agrees well with experimental data and the well-known correlation. Compared with porous media with square grains, the two-phase fluids in porous media with circle grains are more connected and continuous, and consequently the relative permeability is higher. As for the factor of specific porous media surface, the relative permeability of wetting fluids varies a little in two systems with different specific surface areas. In addition, the relative permeability of non-wetting fluid decreases with the increasing of specific surface of porous media due to the large flow resistance.

Fluid-fluid interaction and fluid-solid interaction in the SC LBM model are presented, and schemes to obtain immiscible two-phase flow and different contact angles are discussed. Two-off mechanisms acting on the wetting fluids is proposed to illustrate the relative permeability of wetting fluids varies a little in two systems with different specific surface.

As technical barriers gradually become the important tools of trade protection, it is important to understand whether intensified enforcement of border controls is adopted as a hidden tool of trade protectionism and differs across periods and industries.

This article applies a panel structural vector autoregression (PSVAR) model to investigate the potential role of trade protectionism motives in Food and Drug Administration (FDA) import refusals on China's agricultural exports, utilizing newly constructed monthly data at the industry level.

The results show that import refusal is mainly driven by the inspection history, highlighting the importance of the intrinsic product quality and maintaining an excellent inspection history in border inspection. The novel finding is that US employment contractions would also lead to a small increase in FDA import refusals, especially those taking place within ten months and made without sampling tests. Such an association is driven by industry-specific employment shocks and becomes stronger after the financial crisis. It is also more evident in industries where the US lacks competitiveness against China, being manufactured without mandatory safety regulations, and with negative skewness of employment growth.

This research is one of the preliminary attempts to understand whether the de facto border controls are worked as a hidden tool of protectionism to agricultural products, and what the specific trajectory and duration of the impacts at the monthly level. This study provides empirical evidence showing the role of protectionism motives in FDA import refusals and is heterogeneous across industries, which generate new insights and policy implications to predict and cope with additional barriers on agricultural trade.

The purpose of this paper is to analyse the policy instruments used by the China's Government on prefabricated construction (PC) development, with the aim to clarify the pattern and discover the focus of the policy instruments using the methods of bibliometric analysis and content analysis.

Through a thorough screening by all researchers, 25 policies were identified from 1995 to 2021 were selected and analysed. The external attribute analysis clarified the issuing year, organisation, and the format of each policy. The content analysis was adopted firstly to analyse the policy instrument. An analysis framework including environmental instruments, supply instruments and demand instruments was applied in categorising and counting of each policy instrument. The bibliometric analysis was then carried out to extract keywords of the policy instruments, construct a co-word network and complete the cluster analysis.

The results indicate that the policies lack consistency and had relatively low authority. The results of content analysis show that the policy system relies heavily on environmental and supply instruments, whilst the use of demand instruments seems to be grossly inadequate. The results of the bibliometric analysis identify the core ideas of each policy instrument category, discuss the existing problems and then put forward the corresponding countermeasures.

This study comprehensively and systematically analysed the policy instruments on facilitating the development of PC in China which broaden the research perspectives of the PC development by introducing the methods of political science. The research findings afford helpful information for future policy adjustments and elucidate the effective delivery of policies to facilitate PC development for developing countries.

This study provides an in-depth understanding of policy instruments used by China's Government on PC development. By integrating the policy instrument analysis framework into the mixed methods of content analysis and bibliometric analysis, this study provides an innovative way to conduct policy instrument analysis.