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This paper shows that for a large class of single and multi‐factor term structure models, including the affine class, the market price of risk is directly related to the parameters of the stochastic processes of the underlying factors of the economy. It is shown that the market price of risk is proportional to the limit of the volatility of zero coupon bond returns. This means that the market price of risk is not entirely arbitrary. Not only it must be consistent with no arbitrage conditions, also it must be consistent with the parameters of stochastic processes of the factors that describe the economy. If the market price of risk is not correctly specified, then it could lead to profit opportunities of the type discussed in Backus et al (1996). Another consequence of our result is that in empirical tests of interest rate processes, the market price of risk should not be specified exogenously since its value is a function of the parameters of the model. We extend our result to forward processes. The market price of risk is shown to be a function of the volatility of the forward rate processes.

Successful implementation of construction projects is one of the crucial factors for the economic development of every country. The main part of the countries’ capital is allocated to civil and infrastructure projects annually, most of which are accomplished with delay. Construction projects are often criticized for overrunning time and budgets. Analyzing the factors causing delay is essential for omitting them and timely implementation of these projects. Due to the importance of oil projects, this study aims to investigate and analyze the factors causing a delay in Iran’s oil construction projects.

In this research, after a broad literature review, using the fuzzy Delphi method, a total of 75 delay factors were identified under 11 major categories of owner, contractor, consultant, equipment, labor, materials, design, contract and contractual relations, laws and regulations, environmental factors, and managerial factors. Then, by using the best-worst method, the factors were prioritized.

The results showed that sanction, governmental management systems, weak project management by the contractor, technical and managerial weaknesses of the consultant, financial problems and delay in payment by the owner, low efficiency of the equipment, low productivity of the workforce, changes in laws and regulations, inappropriate organizational structure linking to the project, changes in the design, and changes in the price of materials are the most crucial factors causing a delay in Iran’s oil construction projects.

These findings are expected to have significant contributions to Iran’s oil construction industry in controlling the time overruns in construction contracts.

The main contribution of this study is to develop a comprehensive framework in which, causes of delay in Iran’s oil construction projects are addressed and prioritized.

The purpose of this study is to achieve the low-cost, light-weight and compact antenna array with wide bandwidth and low side lobe levels for synthetic aperture radar (SAR) applications in Ku frequency band.

A compact design of a rectangular microstrip patch antenna array using multilayered dielectric structure is presented in Ku-band for advanced broadband SAR systems. In this design, stepped pins are used to connect the microstrip feed lines to the radiating patches.

The simulation and fabrication results of the multilayered antenna and a 1×16-element linear array of the antenna with Taylor amplitude distribution in the feeding network are presented. The antenna element has a 10-dB impedance bandwidth of more than 26%, and the linear array shows reduction in bandwidth percentage (about 15.4%). Thanks to Taylor amplitude tapering, the side lobe level (SLL) of the array is lower than −24 dB. The maximum measured gains of the antenna element and the linear array are 7 and 19.2 dBi at the center frequency, respectively.

In the communication systems, a high gain narrow beamwidth radiation pattern achieved by an array of multiple antenna elements with optimized spacing is a solution to overcome the path loss, atmospheric loss, polarization loss, etc. Also, wideband characteristics and compact size are desirable in satellite and SAR systems. This paper provides the combination of these features by microstrip structures.

To ensure effective national governance, it is essential to enhance employees' well-being in the workplace. Employees with good mental and physical health are more likely to demonstrate a high level of commitment and engagement in advancing public policy objectives, which serve as instruments of public will. A comprehensive understanding of the various effective strategies to improve workplace well-being is indispensable to formulating human resource management policies within the public sector. Therefore, this study aims to uncover and prioritize the key strategies, programs and actions that contribute to enhancing the workplace well-being of public employees in Iran, drawing from their perspectives and experiences.

We conducted a mixed-method study incorporating both qualitative and quantitative phases to recognize and measure these strategies. In the first phase, a qualitative content analysis was carried out based on the perspectives of Iranian public sector employees. In the subsequent phase, a questionnaire derived from the qualitative findings was randomly distributed to 374 employees from 14 public organizations.

Workplace well-being strategies can be summarized according to the level of their importance as follows: employees' well-being through “inter-personal relationship,” “systems,” “technologies,” “structure,” “culture” and “environment” within the organization. These strategies as six themes divided into 13 categories and 60 subcategories of programs and actions to promote employee well-being in the work setting.

The importance of considering employees' perspectives on workplace well-being is highlighted as a crucial aspect, rather than depending exclusively on managerial viewpoints for the implementation of well-being initiatives. Adopting an integrated and holistic approach to workplace well-being through strategies, programs and actions is another significant contribution of this study.

Religious and peculiar beliefs are two of the factors affecting consumer behavior and may differentially affect individuals and societies. Therefore, this study aims to investigate them from the study of Iranian customers’ behavior.

These beliefs are sensitive issues, hence, to investigate them, the grounded theory method through 15 in-depth interviews was applied.

The results indicated that evil-eye effect, as a peculiar belief, affected the behavior of luxury cars’ consumers in the Iranian society while religion had no such effect on the consumers’ behavior, in spite of religious notions about luxury. Furthermore, the findings revealed that consumers may legitimize their inconsistent behaviors through a variety of tactics such as different interpretations of religious notions or dissembling their superstitious beliefs.

The present study will contribute to the literature on religion and customer behavior through taking advantage of the application of a qualitative research design. Besides, the originality of the study might be in the application of various tactics by the customers to legitimize their behaviors inconsistent with religion.

The purpose of this paper is to survey the prevalence of exposure to workplace violence (WPV) including physical violence, verbal abuse, bullying as well as its related factors among physicians and medical students attending teaching hospitals of Kurdistan University of Medical Sciences (KUMS).

This is a descriptive analytic as well as a cross-sectional study which was carried out on all physicians (general and specialists) and medical students attending teaching hospitals of KUMS in 2014. Overall, 400 participated in this study and data were gathered using a standard questionnaire. Then, data were analyzed using SPSS 20, χ² and Fisher’s exact tests as well as univariate and adjusted logistic regression.

The prevalence of physical violence, verbal abuse and bullying among medical students was reported 4.5, 59 and 0.8 percent, respectively. In addition, the prevalence of these violence among general practitioners was 6.9, 72.4 and 0 percent, respectively. Moreover, 11.5, 42.3 and 3.8 percent of specialists had experienced physical violence, verbal abuse and bullying, respectively. Patients and their relatives were the main sources of the violence. Based on the results of multivariate logistic regression, male sex (AOR=2.60, CI: 1.56–4.32) and having shift work (AOR=3.13, CI: 1.67–5.84) were the most significant risk factors for total WPV.

The WPV experienced by physicians and medical students attending teaching hospitals of MUK is high. Health sector authorities should develop and implement proper strategies and interventions aiming at reducing or preventing from incidence of WPV.

Advergames have attracted the attention of scholars and practitioners as a new way of increasing customer engagement and advertising effectiveness. Gamified ads provide an exciting and persuasive environment for customers rather than non-gamified advertisements. Despite the growing spending on advergames projects, the understanding of customer attitude regarding advergames has received less attention and there are not enough studies about advergames. Therefore, the purpose of the current study is to design a novel TAM-based model of determinants of customer attitudes toward advergames to enhance customer engagement and purchase intention.

To obtain this end, the mixed method was applied. In the first step, the main determinants of customer attitude towards advergames were identified by a literature review as well as semi-structured interviews. In the second step, the proposed technology acceptance model (TAM)-based model was validated by survey method through players of advergames. A total of 15 interviews were conducted in the qualitative phase and 102 completed questionnaires were analyzed in the survey method.

The results of the qualitative approach indicate that the main determinants of attitude towards advertisements can be classified into three categories, which are added to TAM as external variables. The results of the survey approach reveal that advertising content and game-related factors have a significant positive effect on perceived ease of use (PEOU). The advertising content and player-related factors also significantly affect perceived usefulness (PU). PU and PEOU also positively and significantly affect customer attitude. The findings show that the new TAM-based model can be considered as a robust model for explaining customer attitude toward advergame acceptance.

The research findings can assist digital marketers to have a big picture of customer attitudes regarding advergames and implement these innovative digital-enabled advertising strategies successfully. The findings further suggest considering marketing/advertising aspects and game-related aspects as well as individual factors to design advergames.

Advergames have become one of the priorities for digital marketers to enhance brand awareness and customer engagement, yet there is no study identifying determinants of attitude by considering multi-aspects of advergames. The most important theoretical contribution of the current study is to design a new extended TAM-based model which integrates behavioral variables (PEOU and PU) with factors related to the advergames context.

Project portfolio management (PPM) is a commonly used technique to align projects with strategy and to ensure adequate resourcing for projects. In this paper, to gain a better understanding of PPM dynamics, a system dynamics (SD) model was developed. To do so, an Iranian independent power producer was used as a case study in the energy sector; moreover, policy options were derived and generalized for such a developer company.

To cope with the complexity of business processes in a power producer company and to formulate an optimum policy, causal relations and loops were derived first and then state-flow diagrams were designed to simulate the problem in the system, as it is usual in the SD methodology.

The proposed model was applied to a real-world case study to rectify managers’ viewpoint about their business dynamics and to formulate new project portfolio strategies to improve the viability of the company. The model proved how a static portfolio analysis can misguide managers in planning their project portfolio strategies, and how effective feedback can improve PPM in developing companies in the energy sector.

Systems approach, especially SD methodology, has been rarely used to analyze PPM problems in the energy sector. This study highlights the implications of feedback and dynamics in PPM and tries to derive optimal value of portfolios.

This study investigates consumers' willingness to adopt genetically modified foods (GM) and the role of innovation and behavioral determinants.

A new integrated model that expands the Health Belief Model (HBM) into the Innovation Diffusion Theory (IDT) was developed and examined. A total of 241 consumers were selected from the capital of Iran, Tehran, through a multistage random sampling. The data were analyzed using SEM-PLS modeling.

The extended HBM model was able to predict about 84% of the variance changes in consumers' willingness to adopt GM foods. The effects of net benefit and perceived compatibility on the willingness were also significant. In addition, the mediating effect of compatibility on the relationship between net benefit/self-efficacy and willingness to adopt GM foods was also significant.

This study contributes to the literature by developing the HBM into the IDT to assess consumers' willingness to adopt GM foods.

The production-distribution (P-D) problems are two critical problems in many industries, in particular, in manufacturing systems and the supply chain management. In previous researches on P-D planning, the demands of the retailers and their inventory levels have less been controlled. This may lead into huge challenges for a P-D plan such as the bullwhip effects. Therefore, to remove this challenge, the purpose of this paper is to integrate a P-D planning and the vendor-managed inventory (VMI) as a strong strategy to manage the bullwhip effects in supply chains. The proposed P-D-VMI aims to minimize the total cost of the manufacturer, the total cost of the retailers, and the total distribution time simultaneously.

This paper presents a multi-objective non-linear model for a P-D planning in a three-level supply chain including several external suppliers at the first level, a single manufacturer at the second level, and multi-retailer at the third level. A non-dominated sorting genetic algorithm and a non-dominated ranking genetic algorithm are designed and tuned to solve the proposed problem. Then, their performances are statistically analyzed and ranked by the TOPSIS method.

The applicability of the proposed model and solution methodologies are demonstrated under several problems. A sensitivity analysis indicates the market scale and demand elasticity have a substantial impact on the total cost of the manufacturer in the proposed P-D-VMI.

Although the P-D planning is a popular approach, there has been little discussion about the P-D planning based on VMI so far. The novelty comes from developing a practical and new approach that integrates the P-D planning and VMI.