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This study aims to investigate the effect of the dynamics and potential of the board of directors on investment efficiency and the comparability of financial information in companies listed on the Tehran Stock Exchange.

The number of observations for this study includes 1,218 observations from companies listed on the Tehran Stock Exchange during 2014–2020. The authors used econometric statistical methods such as multiple linear regression, the Chow and Hausman test and the Kendall correlation coefficient using Eviews software to conduct the research. To measure the board’s effectiveness, two variables are used, including board dynamics and potential.

The results showed a positive and significant relationship between dynamics, board potential and investment efficiency. Also, no significant relationship was observed between the board dynamics and the comparability of financial information. Finally, a positive and significant relationship exists between the board’s potential and the comparability of financial information.

The importance of this research is the use of board proxies, including the dynamics and potential of the board. In addition, other variables of board characteristics, such as size, independence, ownership and gender, and the relationship between these variables with investment efficiency and comparability of financial information, have been examined in this study.

This study aims to investigate the efficacy of Ag@GO/Na₂SiO₃ nanocomposite in eliminating As from aqueous solutions. Employing response surface methodology, the research systematically examines the adsorption process.

Various experimental parameters including sample pH, contact time, As concentration and adsorbent dosage are optimized to enhance the As removal process.

Under optimized conditions, the initial As concentration, contact time, pH and adsorbent dosage are determined to be 32 ppm, 50 mins, 6.5 and 0.4 grams, respectively. While the projected removal of As stands at 97.6% under these conditions, practical application achieves a 93% removal rate. Pareto analysis identifies the order of significance among factors as follows: adsorbent dosage > contact time > pH > As concentration.

This study highlights the potential Ag@GO/Na₂SiO₃ as a promising adsorbent for efficiently removing industrial As from aqueous solutions, and it is likely to have a good sufficiency in the filtration of water and wastewater treatment plans to remove some chemical pollution, including paints and heavy metals.

The simplicity of the nanocomposite preparation method without the need for advanced equipment and the cheapness of the raw materials and its potential ability to remove As are the prominent advantages of this research.

This study’s aim is to introduce a high-performance sorbent for the removal of both anionic (Congo red; CR) and cationic (methylene blue; MB) dyes from aqueous solutions.

Sodium silicate is adopted as a substrate for GO and AgNPs with positive charge are used as modifiers. The synthesized nanocomposite is characterized by FTIR, FESEM, EDS, BET and XRD techniques. Then, some of the most effective parameters on the removal of CR and MB dyes such as solution pH, sorbent dose, adsorption equilibrium time, primary dye concentration and salt effect are optimized using the spectrophotometry technique.

The authors successfully achieved notable maximum adsorption capacities (Qmax) of CR and MB, which were 41.15 and 37.04 mg g⁻¹, respectively. The required equilibrium times for maximum efficiency of the developed sorbent were 10 and 15 min for CR and MB dyes, respectively. Adsorption equilibrium data present a good correlation with Langmuir isotherm, with a correlation coefficient of R2 = 0.9924 for CR and R2 = 0.9904 for MB, and kinetic studies prove that the dye adsorption process follows pseudo second-order models (CR R2 = 0.9986 and MB R2 = 0.9967).

The results showed that the proposed mechanism for the function of the developed sorbent in dye adsorption was based on physical and multilayer adsorption for both dyes onto the active sites of non-homogeneous sorbent.

The as-prepared nano-adsorbent has a high ability to remove both cationic and anionic dyes; moreover, to the high efficiency of the adsorbent, it has been tried to make its synthesis steps as simple as possible using inexpensive and available materials.

This paper aims to examine how leadership style in audit firms influences audit quality. The paper further explores the mediating role of knowledge sharing in the relationship between leadership style and audit quality.

The present paper studies the effects of transformational and servant leadership styles on audit quality through knowledge sharing. Data are collected from 396 Iranian external auditors via a questionnaire.

The results show that both transformational and servant leadership style significantly influence audit quality through knowledge sharing. Moreover, the impact of transformational leadership style is stronger than the impact of servant leadership style.

In audit quality literature, little attention has been devoted to both leadership style and knowledge sharing. This paper develops a parsimonious model which shows how leadership style improves audit quality, and how knowledge sharing strengthens the impact of leadership style on audit quality. The results have important implications particularly for audit industry.

本文探討審計公司內的領導風格會如何影響審計質量; 本文亦進一步探索、在領導風格與審計質量的關聯上、知識共享所扮演的調節角色。

本文旨在研究透過知識共享、轉型領導風格和僕人式領導風格會如何影響審計質量。數據取自396名伊朗外聘審計員，方法是透過一份調查問卷而進行的。

研究結果顯示、轉型領導風格和僕人式領導風格兩者均會透過知識共享、影響著審計質量，而且，這影響是頗為顯著的。就影響的程度而言，轉型領導風格的影響則較僕人式領導風格的更為強烈。

在研究審計質量的文獻裡，學者對領導風格和知識共享這兩個課題均沒多大關注。本文建立了一個簡約模型，去顯示領導風格如何能改善審計質量，以及知識共享如何能增強領導風格對審計質量的影響。研究結果給予我們重要的啟示，尤對審計行業而言。

This paper aims to present a numerical investigation on laboratory-scale segmental baffles shell-and-tube heat exchanger (STHX) having various tube bundles and baffle configuration.

To discover the higher performance the thermohydraulic behavior of shell-side fluid flow with circular, elliptical and twisted oval tube bundles with segmental and inclined segmental baffled is compared. Shell side turbulent flow and heat transfer are simulated by a finite volume discretization approach using SolidWorks Flow Simulation. To achieve greater configuration performance of this device, the following two approaches is considered: using the inclined baffle with 200 angles of inclination and applying the different tube bundle.

Different parameters as heat transfer rate, pressure drop (Δp), heat transfer coefficient (h) and heat transfer coefficient to pressure drop ratio (h/Δp) are presented and discussed. Besides, for considering the effect of pressure penalty and heat transfer improvement instantaneously, the efficiency evaluation coefficient (EEC) in the fluid flow and heat transfer based on the power required to provide the real heat transfer augmentation are used.

Obtained results displayed that, at the equal mass flow rate, the twisted oval tubes with segmental baffle decrease the pressure drop 53.6% and 35.64% rather than that the circular and elliptical tubes bundle, respectively. By comparing the (h/Δp) ratio, it can result that the STHX with twisted oval tubes bundle (both segmental and inclined baffle) has better performance than other kinds of the tube bundles. Present results showed that the values of the EEC for all provided models are higher than 1, except for elliptical tube bundles with segmental baffles. The STHX with twisted oval tube bundles and segmental baffle gives the highest EEC value equal to 1.16 in the range of investigated mass flow.

The purpose of this paper is to design a qualitative model of crowdfunding dynamics through the document model building (DMB).

Methodology in this paper is the qualitative system dynamics through DMB. In DMB, the authors identify the variables that are drivers of its growth and collapse, and the model will be developed by using the systematic review of the literature.

Designing of the dynamics of crowdfunding model through DMB. Identifying variables that are drivers of crowdfunding growth and collapse. Determining leverage points in crowdfunding diffusion.

This paper, for the first time, with the aim of identifying and explaining the efficient positive and negative dynamics in this method, examines crowdfunding systematically and structurally.

Because of importance of technological learning for less developed countries, the notion has received increasing attention of scholars. The purpose of this paper is to investigate technological learning systematically by assessing the effect of technology transfer actors on technological learning in less developed countries context.

The paper presents assessment model by adopting technological learning concept based on technology absorption and incremental innovation at firm level and identifying key roles of technology transfer actors (State – Scientific and technological infrastructure – Industry) that affect technological learning. The paper follows survey as research methodology. Thus, a questionnaire was addressed to 33 Syrian textile factories to examine the assessment model. Simple linear, multiple linear and ordinal regression analyses are preformed to examine relationships of model components.

The regression models show notable ability of technology transfer actors to explain technological behavior of firms to accumulate operative capability and consequently to generate passive incremental innovation. The findings indicate passive technical change system of Syrian textile industry. Therefore, goal-oriented evaluation of actual technology policy is preliminary step for achieving improvements, as well as activating scientific and technological infrastructure role by enabling strong relationships with industry and supporting interactions of domestic firms of textile industry and with foreign players.

The paper enriches technological learning literature by proposing systematic approach that sets the nature of technical change process of less developed countries in core of analysis. Moreover, it provides a guide for technological learning practices at firm level and for policymakers based on assessing actual status of Syrian textile industry.

Employees, as the most important assets of an organization, acquire a great deal of experience, skills and knowledge throughout the time period they work for the organization. If their skills and technical knowledge are not documented properly, these will be lost once the employees leave the organization. Therefore, documentation is necessary for preserving this invaluable knowledge, avoiding duplication and preventing repeated mistakes that occurred in the past and, providing the junior staff with experiences gained by their predecessors. Thus, this research aims to elaborate on the role of organizational knowledge management (KM) as an essential tool for turning tacit knowledge into explicit knowledge and sharing the gained experiences with others.

This research is developmental applied research with qualitative approach and it was conducted using thematic analysis method. This method includes a semi-structured interview with 18 researchers conducting research projects at the Satellite Research Institute under the supervision of the Iran Space Agency.

The projects contain knowledge that is a combination of “know why”, “know what”, “know who” and “know how”. A large amount of this knowledge is, indeed, the tacit knowledge. Most of this tacit knowledge is not reflected in the project documents. Generally, the documents contain results only and they do not include experience, technical details, methodology, analysis and mistakes that were made during research activities. Documentation challenges fall into three major types: technical, human resources and administrative.

Considering the necessity of documentation within the knowledge transfer process and its important role in KM; and, with respect to the lack of technical knowledge and experience transfer observed in the documents of Satellite Research Institute, this research proposes some steps that need to be taken to turn the knowledge sharing into an organizational culture.

This paper aims to propose an innovative adaptive control method for lower-limb rehabilitation robots.

Despite carrying out various studies on the subject of rehabilitation robots, the flexibility and stability of the closed-loop control system is still a challenging problem. In the proposed method, surface electromyography (sEMG) and human force-based dual closed-loop control strategy is designed to adaptively control the rehabilitation robots. A motion analysis of human lower limbs is performed by using a wavelet neural network (WNN) to obtain the desired trajectory of patients. In the outer loop, the reference trajectory of the robot is modified by a variable impedance controller (VIC) on the basis of the sEMG and human force. Thenceforward, in the inner loop, a model reference adaptive controller with parameter updating laws based on the Lyapunov stability theory forces the rehabilitation robot to track the reference trajectory.

The experiment results confirm that the trajectory tracking error is efficiently decreased by the VIC and adaptively correct the reference trajectory synchronizing with the patients’ motion intention; the model reference controller is able to outstandingly force the rehabilitation robot to track the reference trajectory. The method proposed in this paper can better the functioning of the rehabilitation robot system and is expandable to other applications of the rehabilitation field.

The proposed approach is interesting for the design of an intelligent control of rehabilitation robots. The main contributions of this paper are: using a WNN to obtain the desired trajectory of patients based on sEMG signal, modifying the reference trajectory by the VIC and using model reference control to force rehabilitation robot to track the reference trajectory.

The purpose of this study is to investigate children’s school lunchboxes and explore the influence of carer’s perceived benefits and barriers towards healthy eating on the food contents packed for lunch.

Drawing on exchange theory, the study explores the relationship between carer’s perceived benefits and barriers towards healthy eating and the lunchbox contents a carer packs for their child. An online survey was completed by 876 parents and carers. Statistical analysis techniques, including one-way ANOVA and exploratory factor analysis (EFA) were used to analyse the data.

The analysis revealed that perceived benefits and barriers towards packing healthy foods had a significant impact on the reported contents packed for lunch. Results indicate the segment with the highest perceived benefits and the lowest perceived barriers towards packing healthy lunches reported packing healthier foods than the remaining three segments.

Social marketers should develop interventions to promote the benefits of healthy eating, while overcoming the perceived (and real) barriers that prevent healthy lunches from being packed. Study limitations and future research directions are outlined.

Drawing on exchange theory, the current study demonstrated how simultaneous measurement of benefits and barriers that are later divided into high and low groups impacts lunchbox packing behaviours (Nelson et al., 2010). This study contributes to the literature providing further empirical evidence that use of commercial marketing theories in social marketing is warranted and that theoretically derived segmentation approaches are available for social marketing practitioners.