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The purpose of this paper is to investigate the variables of the fused deposition modelling (FDM) process and improve their effect on the mechanical properties of acrylonitrile butadiene styrene (ABS) components reinforced with copper microparticles.

In the experimental approach, after drying the ABS granule, it was mixed with copper microparticles (at concentrations of 5%, 8% and 10%) in a single screw extruder to fabricate pure ABS and composite filaments. Then, by making the components by the FDM process, the tensile strength of the parts was determined through tensile strength tests. Taguchi DOE method was used to design the experiments in which nozzle temperature, filling pattern and layer thickness were the design variables. The analysis of variance (ANOVA) and signal-to-noise analysis were conducted to determine the effectiveness of each FDM process parameter on the ultimate tensile strength of printed samples. Following that, the main effect analysis was used to optimize each process parameter for pure ABS and its composite at different copper contents.

The study allows the layer thickness and filling pattern had the highest effects on the ultimate tensile strength of the printed materials (pure and composite) in the FDM process. Moreover, the results show that the ultimate tensile strength of the ABS composite containing 5% copper was nearly 12.3% higher than the pure ABS part. According to validation tests, the maximum error of experiments was about 0.96%.

In this paper, the effect of copper microparticles (as filling agent) was investigated on the ultimate tensile strength of printed ABS material during the FDM process.

This paper aims to explain, first of all, signal modeling steps using Poincaré, and then considering the occurred events, concept of information applying Poincaré section and information approach, the brain pattern variations in autism spectrum disorder (ASD) cases will be diagnosed. A kind of representation of electroencephalogram (EEG) signal, namely, complementary plot, in which the main characteristic is special attention to asymmetry and symmetry coexist in natural and human processes, is introduced. In this paper, a new model is provided whose variations of patterns are similar to EEG’s when the transformation parameter is changed. A significant difference between ASD and healthy cases was also observed, which could be used to distinguish between various types of systems.

Complementary plot method is one of the most proper representations for Poincaré section of complex dynamics, because, as it was said about its characteristics, it has a qualitative approach toward signal (Sabelli, 2000, 2001, 2003, 2008, 2005, Sabelli et al., 2011). Considering the special conditions of this representation, here, intersection with a circle y² + x² = r² will be used; the important fact is, on the contrary to previous representations in which circular section had energy concept, here circular section considers phases. For finding trajectory intersection points, after calculating the sin and cosine of each term of EEG, plotting them in XY plane and drawing a chord between successive points of presentation transitions, then its intersections with the assumed circle are determined. But considering the sampling frequency, chords and Poincaré section, in this space, a minimum error – as the threshold – should be assumed in the program.

Natural and human processes are biotic (life-like) and creative (Sabelli and Galilei), and studying coexisting opposites by calculating the sine and cosine of each term in heartbeat intervals, weather variables and integer biotic series or random walk reveals an astonishingly regular mandala pattern; these patterns are not generated by random, periodic or chaotic series (Sabelli, 2005). This paper shows that in EEG of ASD children, mandala-like patterns of concentric rings are emergent in all situations (baseline – watching animation with voice and without voice) and electrode site (C3 and C4), but not in healthy individuals. The authors take the relation between sine and cosine functions as a mathematical model for complementary opposition, because it involves reciprocity and orthogonality sine and cosine are natural models for information. In fact, trigonometric analyses of empirical data to be described in this paper suggest expanding the concept of co-creative opposition to include uncorrelated opposites and partial opposites, i.e. partial agonists and partial antagonists that are neither linear nor orthogonal. Using Poincaré sections, it is shown that the difference in information and creativity of the data is the distinctive characteristic in ASD and healthy cases. Creation is the generation of novelty, diversity and complexity in complex systems.

This paper is an original paper based on cybernetic approaches for studying the variations of ASD children.

Informed by the Bourdieusian construct of the social field, the purpose of this paper is to explore how different aspects of the educational field and the sub-field of English language teaching in Iran influence diverse components of the professional identity of high school EFL teachers. To this aim, the impact of the power hierarchization structure, distribution of capitals and field autonomy, as important aspects of the social field theory, is investigated in relation to Iranian EFL teachers’ professional identity construction.

Van Manen’s (1990) hermeneutic phenomenological research method was adopted to analyze the data obtained through the semi-structured interviews and reflexive journals from 15 Iranian EFL teachers at high schools.

The hermeneutic phenomenological analysis of the data yielded to the extraction of one global, three organizing and six basic themes. The global theme was the educational field and professional identity. The resulting organizing themes were: first, autonomous field and teachers’ commitment; second, asymmetric power relation and teachers’ autonomy; and, finally, cultural capital and teachers’ motivation. This study revealed how the complex and multi-dimensional nature of the power relations between the field of education and power influenced the professional identity of EFL teachers.

This dynamic representation of the inherent complexities of the educational context contributes to a more profound understanding of the role of the micro and macro contextual factors in formulating teachers’ professional identity. The implications of this study are further explained.

Hereby, the authors declare that all the procedures of data collection and analysis have been just done by the researchers.

The purpose of this paper is to propose an applicable method for establishing the dynamic inter-organizational collaborations (DIOCs) based on the scrum methodology.

The scrum methodology embedded within the context of the DIOC project life cycle was used and adapted to being usable with specific characteristics of the project.

In order to succeed in the highly competitive, dynamic and changing business environments, the organizations need to change their view of business practices. The transition from the traditional status of manufacturing to the inter-organizational collaborations can be one of the fundamental changes in the modern business management. The proposed method has the capability to establish DIOCs effectively and efficiently whilst guaranteeing agility, competitiveness, and risk timely management.

Establishing collaborative alliances via association of various experienced and professional organizations and producing the value-added market’s need services is an effective and efficient solution for survival of SMEs in the current competitive, dynamic and changing business environment. So far, different frameworks, reference models/architectures, and many theoretical discussions have been presented for DIOCs context, but these representations are conceptual, empirical and generic. This paper aims to propose an applicable iterative and incremental method for establishing the DIOC which guarantees the agility and risk timely management of the establishment process and promotes competitiveness of partners.

Institutional changes, in a historical context, through simultaneous evolutionary and metamorphic processes either deform or reform long-enduring institutions. The chapter delves into the Persian history from the early days of the reign of Nāṣer al-Dīn Shāh-e Qājār in 1848 to the recent years and traces Persian institutions' historical transformations, which culminated to the Persian women entrepreneurship. Thus, the chapter first sets the historical context in each period and then sheds light on the pivotal issues of each period's women. The undergirding base of the discussions is the assumption of the change in institutions as natural metamorphosis in the animate. Finally, the discussions contribute to the conceptualization of the Institutional Triangulation and in the case of Persia, a cultural-driven triangulation, which has paved the way to the formation of a stupendously hegemonic patriarchal and masculine sociopolitical economy in Persia, that has historically affected women's institutionalization, subjugation, subordination, marginalization, socialization, emancipation, and most recently Islamization phases.

The contemporary landscape of supply chains necessitates a comprehensive integration of multiple components encompassing production, distribution and customer engagement. The pursuit of supply chain harmony underscores the significance of pricing strategies within the framework of dual-channel distribution, particularly when confronted with the dynamics of asymmetric demand performance.

This paper delves into a nuanced decision-making challenge anchored in a dual-channel distribution context featuring a retailer and two distinct products. Notably, the retailer’s decision-making process employs the computational framework of dual grey numbers, a robust tool for handling uncertainty.

This study revolves around applying game theory to manufacturers. Each manufacturer presents its aggregated price proposition to the retailer. Subsequently, the retailer identifies the optimal pricing configuration among the manufacturers' aggregate prices while adhering to constraints such as spatial classification and inventory costs. This article’s contribution extends to delineating the retailer’s capacity to discern the influence of product market potential and the aggregate product cost on the overall demand.

The model’s innovation lies in its harmonious fusion of spatial classification, pricing strategies and inventory control. Notably, this novel integration provides a platform for unraveling the intricate interplay between non-symmetric market potential, production costs and cross-sensitivity. The investigation is underscored by the utilization of the double interval grey numbers, a powerful computational approach that accommodates the inherent uncertainty pervasive in the domain. This study fills a gap in the existing literature by offering an integrated framework unifying spatial allocation, pricing decisions and inventory optimization.

Hospitals are all required to be prepared against crisis, while according to studies, most hospitals are not prepared enough to encounter disaster problems. Therefore, each hospital should have an established programme to face earthquake and other catastrophes. This paper aims to investigate this issue.

This descriptive study was carried out in teaching hospitals of Iran University of Medical Sciences. Data collection was done using a checklist including general information, as well as information on demography, security, supplies and equipment, evacuation and communication. This procedure was done through observation and interview with hospital managers, etc. and the data were analyzed by SPSS software.

In the hospitals four dimensions of planning were studied and the following mean scores were obtained. On security, Hazrat Rasul hospital scored the highest (88.4) while Navab Safavi, Haftome Tir and Ali Asghar hospitals scored the lowest (51.4). On supplies and equipment, Navab Safavi and Haftome Tir hospitals obtained the highest score (66.6) and Hasheminejad, Shafa Yahyaeian, Firoozgar and Hazrat Rasul hospitals got the lowest score (60.0). On evacuation, Hazrat Rasul and Haftome Tir hospitals scored the highest and lowest respectively (64.2), (47.0). On communication, Hasheminejad hospital scored the highest (63.2) while Firoozgar hospital scored the lowest (36.6). In general from among ten hospitals under study the most and the least prepared hospitals were Hazrat Rasul and Navab Safavi respectively (65.65), (54.3).

The paper shows that most hospitals under study were not prepared enough against crisis and communication is found to be the weakest aspect although it is regarded as a basic principle in planning. Hazrat Rasul hospital was well prepared against crisis due to its disaster plan.

Every day, small and big incidents happen all over the world, and given the human, financial and spiritual damage they cause, proper planning should be sought to deal with them so they can be appropriately managed in times of crisis. This study aims to examine humanitarian supply chain models.

A new model is developed to pursue the necessary relations in an optimal way that will minimize human, financial and moral losses. In this developed model, in order to optimize the problem and minimize the amount of human and financial losses, the following subjects have been applied: magnitude of the areas in which an accident may occur as obtained by multiple attribute decision-making methods, the distances between relief centers, the number of available rescuers, the number of rescuers required and the risk level of each patient which is determined using previous data and machine learning (ML) algorithms.

For this purpose, a case study in the east of Tehran has been conducted. According to the results obtained from the algorithms, problem modeling and case study, the accuracy of the proposed model is evaluated very well.

Obtaining each injured person's priority using ML techniques and each area's importance or risk level, besides developing a bi-objective mathematical model and using multiple attribute decision-making methods, make this study unique among very few studies that concern ML in the humanitarian supply chain. Moreover, the findings validate the results and the model's functionality very well.

The application of correct contractor selection strategies leads to the selection of a qualified contractor and, as a result, the on-time delivery of the project with the desired quality and within the predetermined budgetary constraints. For this reason, evaluating and qualifying contractors before reviewing the proposed prices has been considered an important issue. One factor that disrupts the project completion process and the failure to achieve pre-planned goals effectively is the occurrence of contractors' disputes and claims in projects. To this end, the present study explores claim-reduction strategies for selecting effective contractors in an uncertain environment to reduce possible problems.

The two-step grey data envelopment analysis (GDEA) approach was used to measure efficiency as a powerful tool in selecting efficient contractors during tenders. This approach can extend the applications of multi-criteria decision-making (MCDM) models. In other words, given some uncertainties, the unavailability of some data, and the problems with the DEA model, the two-step GDEA model was used to rank the contractors. The data confirmed the satisfactory outcomes from the selected model.

The preliminary assessment of contractors is a pre-tendering process and a step in categorizing contractors, excluding contractors lacking required qualifications, and selecting efficient contractors. At first, it will help the employer to exclude inexperienced and unqualified contractors, save resources and time, reduce threats, replace opportunities with threats, and reduce material and non-material costs during the completion of the project until the projects are put into operation. Consequently, this approach reduces claims to a minimum level and increases the organization's effective material and non-material profit.

Oil and gas plans and projects have a significant, sensitive, and decisive role in the economic, social, political, cultural, infrastructural, and all-round development of Iran; This is while most of the financial resources needed to implement the development and programs across the country come from oil revenues. Studies have indicated that despite the importance of these plans and projects, many of them are not completed successfully, and this causes irreparable losses to the country's economy and development in various fields.

1. The findings of this study can be used by organizations to select more effective contractors to assign projects and plans to them.

2. The preliminary assessment of contractors is a pre-tendering process and a step in categorizing contractors, excluding contractors who lack required qualifications, and finally selecting efficient contractors.

3. At first, it will help the employer to exclude inexperienced and unqualified contractors, save resources and time, reduce threats, replace opportunities with threats, and reduce material and non-material costs during the completion of the project until the projects are put into operation.

4. This approach also gives credit to the employer during the execution period and contributes to assessing unqualified contractors and reducing the temptation to hand over the project to an unqualified contractor but with a lower bid price.

5. Consequently, this approach reduces claims to a minimum level and increases the effective material and non-material profit of the organization.

6. Moreover, it provides an extra-organizational evaluation for contractors, motivating them to upgrade their capabilities and optimally allocate material and non-material resources, especially human resources.

The findings of this study can be used by organizations to select more effective contractors to assign projects and plans to them.

The preliminary assessment of contractors is a pre-tendering process and a step in categorizing contractors, excluding contractors who lack required qualifications, and finally selecting efficient contractors.

At first, it will help the employer to exclude inexperienced and unqualified contractors, save resources and time, reduce threats, replace opportunities with threats, and reduce material and non-material costs during the completion of the project until the projects are put into operation.

This approach also gives credit to the employer during the execution period and contributes to assessing unqualified contractors and reducing the temptation to hand over the project to an unqualified contractor but with a lower bid price.

Consequently, this approach reduces claims to a minimum level and increases the effective material and non-material profit of the organization.

Moreover, it provides an extra-organizational evaluation for contractors, motivating them to upgrade their capabilities and optimally allocate material and non-material resources, especially human resources.

In recent years, increasing competition in communicational network of Iran has led to attracting more attention to marketing and particularly, advertising activities. The aim of this paper is to examine the effect of TV advertising appeals of communication companies (in this study, MTN Irancell Company) on customers' attitude towards their advertising efforts and their brand.

The aim was achieved through an empirical study involving a survey. Of 400 questionnaires sent out, 384 were returned. The dataset from the sample underwent series of statistical analyses, i.e. reliability test, factor analyses (exploratory and confirmatory) and structural equation modelling (SEM).

Factor analyses extracted seven dimensions, i.e. one‐sided appeal, two‐sided appeal, humour appeal, fear appeal, comparative appeal, attitude toward advertising and brand attitude. All related indicators manifested their constructs, respectively. The results show that there is a positive, direct, and significant relationship between: advertising appeals and attitude towards advertising; advertising appeals and brand attitude; and attitude towards advertising and brand attitude.

The paper empirically justified the interrelationship among advertising appeals, attitude toward advertising and brand attitude in an integrated model. Communication companies may find this paper useful as perceptual measures can be empirically substantiated using SEM.