Optimization

We seek to determine the optimal amount of the insurer’s investment in all types of assets for a small and closed economy. The goal is to detect the implications and contributions the risk seeker and risk aversion insurer commonly make and the effectiveness in the investment decision. Also, finding the optimum portfolio for each is the main goal of the present study. To this end, we adopted the optimal asset-liability management (ALM) method to control the firm's risk of financial stability and growth by balancing the assets and liabilities of the firm. In the process, stochastic interest rates and inflation risks were taken into account according to the expected utility maximization framework. All assets were established and calculated by the Kalman Filter with the stochastic interest rate following the Hull-White model; an additional stochastic process models the inflation risk. To consider the stochastic process, we employed the geometric Brownian motion in the liability process to ensure a definite liability value. We chose Iran’s Social Security Organization as our sample insurer company since it has a portfolio of five types of assets and four types of liabilities, and operates in a small and closed economy. By Applying the ALM method with the stochastic control theory approach, we acquire the optimal investment strategies for insurers to minimize their risk. Our findings demonstrate the effects of model parameters, such as the degree of risk-taking on the insurer decision.

The Supply Chain Network Design (SCND) with perishability is an active research topic. The Agri-fresh Food Supply Chain (AFSC) is a relevant topic to SCND and this study aims to model a new AFSC for a real-world case study. Regarding the traditional AFSC, the geographically dispersed small farmers transport their product individually to market for selling. This leads to a higher transportation cost, which is the major cause of farmers’ low profitability. This paper formulates a traditional product movement model to represent the existing AFSC. The concept of sharing economic approach is employed by the aggregate and collaborative transportation of products to minimize transportation inefficiency. This paper proposes an aggregate product movement with the vehicle routing model to re-design an AFSC for a case study in Iran based on the data of ETKA Company-the largest domestic agri-fresh food supply chain. A four-echelon, multi-period, Mixed Integer Non-Linear Programming (MINLP) approach for the proposed location-inventory-routing model is formulated for perishable products via considering the clustering of farmers to minimize the total distribution cost.

The usage of social theories in the human-built environment caused to enhance life quality. It may consist of human needs in residential areas. Sometimes, building codes can help to exist accepted life space, but the building codes do not have basic theory such as actual open space in residential plots. The study was an attempt to represent a new approach in urban land subdivision and the relationship between social theories and built up area. The research question was how to determine the open- space ratio. Main indicators were related to residential areas in urban areas in Iran which the lot size and urban density appear. The study tried to represent optimum open- space ratio based on Edward Hall's theory. The method was based on mathematical model and social theory. Finally, it resulted in optimum OSR in lot and it was not enough open- space ratios in existing situation.  This study came to this conclusion that existing open- space measure was not enough for any Lot in new residential areas based on mentioned theory. In addition, investigation showed that the human distances effected on open and built up space ratio in a new residential layout. It was concluded that every residential area can have an optimum open- space ratio based on its situation. The results can use new residential layouts for enhancing human-built environments, but it noticed that there are not certain tools for making high-quality environments based on social theories. 

The certainty about retirement income is dependent on the longevity and the selected investment policy by individuals during their working years. Attention to longevity and investment risks is of high significance in making enough income for retirees. In this research, the impact of the objective formulation selection on investment decisions has been investigated. Two functions including terminal wealth objective formulation and retirement income objective formulation are applied to investigate these decisions. Based on the investment alternatives, 5 asset classes including Equity, Certificate of deposit (cash), real estate investment trust (REIT), gold coin, and foreign exchange have been selected for investment. According to the complexity of modeling in the aforementioned functions, the Metaheuristic Genetic algorithm has been used. The results are indicative of the importance of objective formulation selection. The retirement income objective function has the nature of more wealth accumulation and more control over economic and market turbulences through higher cooperation in investment and as a result, it has been recommended as the optimal function.

INTRODUCTION: The frequency of natural disasters is high in Iran due to its special climatic and geophysical conditions. However, the provision of better services to trauma victims requires further research. Decisions on emergency accommodation and meeting the needs of the victims are often made in conditions of uncertainty, and the lack of appropriate studies leads to the provision of low-quality and intermittent services. METHODS: This applied and descriptive-analytical study was conducted to determine the advantages and disadvantages of relief tents using documentary and library resources, observation, and interviews with officials and experts, and the effective standards for the construction system of emergency accommodation. The thermal comfort of the victims was then investigated using the guidelines of the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE), interviews with the victims, and field tests. Moreover, solutions are introduced for the improvement and optimization of relief tents, and a new building system is introduced for the emergency accommodation of victims in incidents by removing the disadvantages of the systems previously used in emergency accommodation. FINDINGS: According to the observations and investigations, the previously used emergency shelters do not meet the needs of the accident survivors properly and their design does not correspond to the users’ culture and needs. The problems with the current accommodating methods include lack of privacy, lack of protection against disturbing cold and heat, and inappropriate and non-standard dimensions of the existing tents. Solutions have been presented to solve the existing problems and a new system for emergency accommodation has been introduced based on field observations and interviews with experts. CONCLUSION: It is noteworthy that the votes of 22 percent of people are in the range of slightly warm to slightly cold; which shows that these people are satisfied with their accommodation regarding thermal comfort. 78 percent of the people's votes were outside the satisfaction range. Due to the chambered structure of the tent, direct sunlight in the summer, the lack of proper air exchange, the weakness of the structural components of the tent and the lack of heat retention in the winter, proper mechanical systems should be used to provide thermal comfort, which is not feasible in practice due to the extent of the incidents and large amounts of equipment and resources needed which bolds the importance of the proposed construction system.

Designing trading systems with good returns is critical for capital market investors. Trading systems are often based on a combination of several tools to use their combined information. For the first time in Iran, the present study aimed to propose a pattern detection algorithm for a flag pattern based on Japanese candlestick charts and their arrangement. By recognizing the pattern and if the 4- and 10-day moving average is confirmed, a shopping position is developed, and the selling time is determined based on an optimized and dynamic process commensurate with price changes and the data scale. Our objective was to address the question of whether the returns resulting from this strategy have a more significant positive return compared to the purchase and maintenance strategy. The research sample included the daily information of 16 active companies of basic metals in Tehran Stock Exchange during 2007-2019, extracted from the database of Novin Rahavard software. Data analysis was performed in MATLAB software, and the obtained experimental evidence was described using t-test. According to the results, the research strategy had a higher performance in terms of returns and risks compared to the market.

Purpose : The study aims to study the effect of architectural design parameters on IEQ in accomplishing school smartification. Method : The research was conducted in school buildings located in Tabriz, Iran. The indicators chosen to represent IEQ are the adaptive PMV model used for thermal comfort, imageless daylight glare probability used for visual comfort, and CO2 concentration used for IAQ assessment. The simulation technique was used to collect data for a generative parametric school model. The method of data analysis includes a multivariate linear regression algorithm, t-test statistic, and one-way analysis of variance. The studied variables are dimensions of classrooms with the fixed area, Percentage of window area on a wall, window height, Shading, and protrusions in plan design. The stepwise method for multivariate linear regression in SPSS was used to assess the vital IEQ indicator in terms of thermal and visual comfort and CO2 concentration. Findings : The study found that among studied indicators, the south facade window ratio significantly correlates with IEQ. The other CRI parameters are the north window ratio and north window height. the findings revealed that to increase the IEQ in schools, facade design is more critical than the plan. The higher the window surface on the south, north, west, and east faces, the greater the thermal comfort and glare probability is. Conclusion : However, increasing the height of the windows can reduce glare and also increase thermal comfort. Thermal comfort improves as the length of the southern classrooms rises. On the bright side, it has no noticeable glare effect.

Purpose – The purpose of this paper is to optimize Cost & time in the three echelon supply chain (SC) network. This paper developed a linear programing (LP) model to consider economic data. Design/methodology/approach – The overall objective of the present study is to use high-quality raw materials, at the same time in post COVID 19 pandemic and the highest profitability is achieved. The model in the problem is solved using two metaheuristic algorithms, namely, Cuckoo and Genetic. Optimization of supply chain performance indicators in minimization of cost and time and maximization of sustainability indexes of the system. Findings – The differences found between the genetic algorithms (GAs) and the LP approaches can be explained by handling the constraints and their various logics. To deal with ambiguity in the reverse logistics network, a fuzzy approach has been applied. To solve the problem in large dimensions, meta-heuristic algorithms of Cuckoo and Genetic were employed by applying MATLAB software. In order to compare two optimization algorithms, a series of sample problems have been generated then the results of two algorithms were compared and superiority of each of them was discussed.

Accounting processes and their related decisions play an important role in organizing business. If the organization does not have a comprehensive accounting system, managing it will face many problems such as liquidity deficit, tax penalties and so on. Therefore, optimizing accounting processes is essential for managing an organization and improves the company's performance and greater efficiency for business activities. On the other hand, estimates and subjective judgments in preparing financial statements have caused controversy among auditors and owners. In particular, in cases where the standards are not clear, the use of unavoidable judgment and mentality creates ambiguity in financial reporting. This is while the ultimate value of audit activity is in helping the user to determine the quality of the information received. On the other hand, the financial reporting crises of recent years have focused the attention of researchers and professional associations on increasing the reliability of audit reports and reducing negligence. Therefore, considering the importance of auditing and the quality of financial reporting, this study examines and analyzes auditing strategies and determines the optimal strategy to improve the quality of financial reporting. For this purpose, 120 companies active in the Tehran Stock Exchange, which have a legal and formal audit system and use external audit firms for auditing, are considered as a statistical sample based on the counting method, and the senior supervisors, managers and partners of this Companies have been questioned.