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This study was conducted to evaluate the effects of different dietary levels of butyric acid on growth performance, immunity and digestive enzyme activities in yellowfin seabream (Acanthopagrus latus) (8.59 ± 0.33 g) at the period of 60 days. After 2-week adaptation, 120 fish with a density of 10 fish/tank in a completely randomized design were distributed to 12 tanks. Fish were fed with 4 levels of butyric acid including zero (control), 2.5 (T1), 5 (T2) and 10 g/kg (T3) of diet 2 times per day. The results showed that different levels of butyric acid in diet had significant effects on growth performance and nutritional indices compared to the control (p0.05). The food conversion ratio in control group was significantly higher than in the other treatments (p0.05). In conclusion, butyric acid, especially at the level of 10 g/kg of diet, displayed positive effects on the growth, immune indices and enzyme activities in yellowfin seabream.

BACKGROUND: Early maladaptive schemas (EMSs) and difficulty in emotion regulation are mechanisms leading to dysfunctional behaviors and reduction of mental health; hence, this study aimed to compare EMSs, emotion regulation, and general health in prisoners and non-prisoners. METHODS: The research method was causal-comparative (post-event). Statistical society comprised all of prisoners and non-prisoners in Fuman City in Iran. Of them, 100 prisoners were selected using random sampling and they were compared with 100 matched non-prisoner men based on the inclusion criteria and. Non-prisoners were matched with prisoners in terms of age, job, and education level. Both groups filled out Young Early Maladaptive Schemas Questionnaire (YEMSQ), Persian version of the Cognitive Emotion Regulation Questionnaire (CERQ-P), and 12-item General Health Questionnaire (GHQ-12). Data were analyzed using independent t-test and multivariate analysis of variance (MANOVA). RESULTS: A significant difference was observed between two groups in total score of EMSs, emotion regulation, and general health (P < 0.001). CONCLUSION: There is a significant difference between two groups in general health, maladaptive schema, and emotion regulation which indicates that EMSs, inability to regulate emotions, and low general health could play a critical role in criminal behaviors.

Background: this study was conducted to examine the effectiveness of emotion regulation and distress tolerance skills training on coping strategies, emotion regulation, and perceived stress in prisoners Method:The esearch method of current study was semi experimental method in form of pretest and posttest with the control group.statistical population consisted of 200 prisoners in Fooman Prison in Iran; of individual who had inclusion criteria, 30 members were selected using convenient sampling method then assigned to two experimental and control groups (n=15 in each group). They were match base on education level and age. Experimental group received 12 sessions teaching of emotion regulation and distress tolerance skills, while control group were waiting. Both groups filled in coping responses, emotion regulation, and perceived stress reduction questionnaires at baseline and after treatment. Data were analyzed using SPSS21 Software. Results: Emotion regulation and distress tolerance skill training could affect improvement of coping strategies, emotion regulation, and perceived stress reduction in prisoners (P

This study was aimed to investigate the distribution of various species of fecal coliform in urban, rural and private drinking water sources of Kermanshah, in the west of Iran. For this study, data of ten years period (2006–2016) assessments of microbial quality regarding various species of Fecal coliforms was taken from health centers associated with urban, rural and private resources of Kermanshah city. A total number of 8643 samples were taken, 1851 samples from rural, 365 from urban and 4834 from private resources. The results showed that Fecal coliforms, Escherichia coli (E. coli) had the widest distribution in all urban, rural and private water resources (22.3%, 45.9% and 34%, respectively). Moreover, E. coli (47.5%) and Klebsiella (0.4%) had, respectively, the highest and lowest distribution in all months considered. Based on the results, E.coli exists mostly in water resources; it is therefore of particular importance in the monitoring of water resources. Keywords: Fecal coliforms, Distribution, Drinking water sources, Kermanshah

We conducted this study to determine the chronic effects of Azadirachtin on growth parameters, survival and gill morphology of grass carp [Ctenopharyngodon idella (C. idella)] with an average weight of 11.09±2.3g. We equally distributed 120 fish between three treatments and a control group, with three replicates each. Sublethal concentrations of poison, 0.073 (10% LC50), 0.15 (20% LC50), 0.22 ppm (30% LC50) were selected. Fish were exposed to these doses for 28 days. Increasing doses of Azadirachtin did not affect growth parameters and survival (P>0.05). During the test, we observed fish behavior patterns of irregular swimming, rotation, reaction increased response versus stimulus exterior, solitary and imbalance, histology, epithelial uplifting (swelling), hyperplasia, fusion of gill lamellae and necrosis of gill epithelial cells. The results showed that although the sublethal dose of Azadirachtin over a short time did not affect growth and survival of C. idella but brought about abnormal behavior in fish. There was increased gill tissue destruction with increased poison levels which showed that it could be effective on long duration of exposure.

Objective(s): Electromagnetic radiations which have lethal effects on the living cells are currently also considered as a disinfective physical agent. Materials and Methods: In this investigation, silver nanoparticles were applied to enhance the lethal action of low powers (100 and 180 W) of 2450 MHZ electromagnetic radiation especially against Escherichia coli ATCC 8739. Silver nanoparticles were biologically prepared and used for next experiments. Sterile normal saline solution was prepared and supplemented by silver nanoparticles to reach the sub-inhibitory concentration (6.25 μg/mL). Such diluted silver colloid as well as free-silver nanoparticles solution was inoculated along with test microorganisms, particularly E. coli. These suspensions were separately treated by 2450 MHz electromagnetic radiation for different time intervals in a microwave oven operated at low powers (100 W and 180 W). The viable counts of bacteria before and after each radiation time were determined by colony-forming unit (CFU) method. Results: Results showed that the addition of silver nanoparticles significantly decreased the required radiation time to kill vegetative forms of microorganisms. However, these nanoparticles had no combined effect with low power electromagnetic radiation when used against Bacillus subtilis spores. Conclusion: The cumulative effect of silver nanoparticles and low powers electromagnetic radiation may be useful in medical centers to reduce contamination in polluted derange and liquid wastes materials and some devices.

Objective(s): Electromagnetic radiations which have lethal effects on the living cells are currently also considered as a disinfective physical agent. Materials and Methods: In this investigation, silver nanoparticles were applied to enhance the lethal action of low powers (100 and 180 W) of 2450 MHZ electromagnetic radiation especially against Escherichia coli ATCC 8739. Silver nanoparticles were biologically prepared and used for next experiments. Sterile normal saline solution was prepared and supplemented by silver nanoparticles to reach the sub-inhibitory concentration (6.25 μg/mL). Such diluted silver colloid as well as free-silver nanoparticles solution was inoculated along with test microorganisms, particularly E. coli. These suspensions were separately treated by 2450 MHz electromagnetic radiation for different time intervals in a microwave oven operated at low powers (100 W and 180 W). The viable counts of bacteria before and after each radiation time were determined by colony-forming unit (CFU) method. Results: Results showed that the addition of silver nanoparticles significantly decreased the required radiation time to kill vegetative forms of microorganisms. However, these nanoparticles had no combined effect with low power electromagnetic radiation when used against Bacillus subtilis spores. Conclusion: The cumulative effect of silver nanoparticles and low powers electromagnetic radiation may be useful in medical centers to reduce contamination in polluted derange and liquid wastes materials and some devices.

Return and risk are significant parameters in selecting an optimal portfolio, depending on the portfolio return distribution. In a stochastic process, the Markov property causes the future distribution of a random process to be measurable according to the state-transition matrix and the initial process state. According to the main idea of the present study in the optimal portfolio selection, portfolio weights are chosen in a way that the Markov property is established for the portfolio return series and the distribution of future portfolio returns is close to the distribution of investor’s expected returns; hence, K-L divergence (Kullback–Leibler divergence) is utilized as a criterion of closeness. Using this idea, an optimal portfolio selection model was designed and implemented in the present study. This optimal portfolio was optimized using a Markov approach and according to historical data of 10 indices on the Tehran Stock Exchange from 2009 to 2022 in a six-member state. The optimal portfolio performance evaluation using the Sharpe ratio and value at risk criteria indicated that the research model had a higher performance than the mean-variance and weight parity models. [ABSTRACT FROM AUTHOR]

This research suggests a Robust and Risk-Averse Medical Waste Chain Network Design by considering Viability requirements (RRMWCNDV). The aim is to locate a waste management facility that minimizes waste and promotes the recycling of materials like metal and plastic, contributing to environmental benefits. The proposed RRMWCNDV aims to be viable, robust and risk-averse. A two-stage robust stochastic programming model was utilized to develop this framework. It incorporates risk by employing the Weighted Value at Risk (WVaR) approach for the first time. The study reveals that incorporating risk and robustness scenarios results in a lower cost function. The degree of conservatism in decision-making can be adjusted between 0% and 100%, increasing the cost function. The confidence level in WVaR indicates risk aversion, with an increase in the cost function with a 4% increase. The agility coefficient, which indicates the percentage of waste demand production from HC transferred to another facility, also affects the cost function and population risk. A decrease in the sustainability coefficient results in a 53% rise in the cost function and a 12.82% increase in population risk. The model demonstrates NP-hard characteristics and becomes exponentially complex for larger scales. [ABSTRACT FROM AUTHOR]

In the present study, using the method of neural networks, the interval related to the lowest and highest daily prices is predicted and, then based on it, a daily scalping trading system is formed, including buying and selling in the forecasted amounts. To reduce the risk of the trading system and increase the number of trading positions, the optimal daily scalping trading portfolio is developed in the mean-variance framework. The sample portfolio includes five shares of the Tehran Stock Exchange in 190-day period, taking into account trading costs, shows that the average daily return is 0.0028 and the Sharpe ratio is 0.6379, which is better than the Sharpe ratio of individual daily scalping trading of portfolio assets. The daily average of the total index in the research period is 0.0014 and the Sharp ratio is 0.0749, which shows that the trading system has a much better performance than the buy-hold strategy in equal-weighted portfolio. [ABSTRACT FROM AUTHOR]

Background: For improving the quality of endodontic performance of practitioners in clinical practice, their basic, preclinical performance and knowledge must be taken into consideration. This study aimed to radiographically evaluate the technical quality of preclinical molar root canal treatments (RCTs) performed by undergraduate dental students at a dental school in Iran. Further, the effect of using Gates-Glidden (GG) drills on the final quality of RCTs was evaluated. Materials and Methods: In this retrospective cross-sectional study,315 roots of 105 endodontically treated teeth in preclinical practice were evaluated radiographically. The analyzed quality parameters included length, taper and density of fillings, which were scored as S2 (adequate standard), the S1 (slight deviation), or S0 (considerable deviation). For all the parameters, acceptable, moderate and poorfillings received total scores of 6,3-5 and 0-2, respectively. There were two groups of students: One group had used only K-files, and the other had used K-files along with GG drills. The quality of RCTs between these groups was evaluated using the aforementioned scoring protocol. The results were analyzed using Chi-square, Mann-Whitney and Fisher's exact tests (α = 0.05). Results: Under-fillings (P = 0.001) and under-shapings (P = 0.007) occurred mostly in mandibular root fillings. A lower density was found in maxillary fillings (P < 0.001 ). No relationship was observed between the technique used (irrespective of GG drills usage) and length (P = 0.499) and taper of fillings (P = 0.238).The roots instrumented with GG drills had a higher filling density (P = 0.004). The quality mean score of RCTs was improved when GG drills were used (P = 0.008). Conclusion: The technical quality of preclinical molar RCTs performed by undergraduate dental students was considered acceptable in 35.6% of the cases. When GG drills were used along with K-files, the technical quality of RCTs was enhanced. [ABSTRACT FROM AUTHOR]

Although developing strategic and operational plans is a difficult and complicated process, their successful implementation is much more difficult. Many organizations fail in the full implementation of their strategies. This is not due to the partial definition of strategies and organization's operational plan, but this is likely due to the lack of strong framework for creating alignment between employees and operational process and the organizational goals. To implement strategies effectively and to develop a comprehensive management system and to improve the performance, Robert Kaplan and David Norton introduced a modern management system which is Balanced ScoreCard. Likewise they introduced five main criteria: leadership, translation, alignment, every day process and ongoing process for a strategy oriented organization. This paper is intended to offer a systematic approach for measuring the effectiveness and efficiency of the strategic plan performance. For this study the questionnaire was distributed in a project- orientated service organization and after collection, by the use of statistical. Analysis especially factor analysis the grouping of sub-criteria under the five main criteria was confirmed. The statistical analysis showed that, two criteria of alignment and every day work had the lowest scores in terms of both implementation and effectiveness in the organization's senior and executive manager's point of view. With deep interview, studying of scorecards and meeting of the strategic committee of the studied organization, the two dimension of alignment and every day work were further examined and after identifying upgradeable areas, some suggestions for improving the effectiveness and efficiency of the studied organization were presented. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this paper is to propose a new algorithm for multilevel stabilization of large scale systems. In two-level stabilization method, a set of local stabilizers for the individual subsystems in a completely decentralized environment is designed. The solution of the control problem involves designing of a global controller on a higher hierarchical level that provides corrective signals to account for interconnections effect. The principle feature of this paper is to reduce conservativeness in global controller design. Here, the key point is to reduce the effect of interactions instead of neutralizing them. In fact, unlike prior methods, our idea does not ignore the possible beneficial aspects of the interactions and does not try to neutralize them. [Copyright &y& Elsevier]

Budget Allocation Problem (BAP) for projects is considered one of the critical risks that necessitate the completion of projects in the shortest possible duration. This aspect is significant in extensive projects such as national endeavors directly impacting people's livelihoods. This research focuses on introducing Sustainable, Robust, Resilient, and Risk-averse Budget Allocation for Projects (S3RBAP). A hybrid robust stochastic optimization approach was employed, incorporating Weighted VaR (WVaR) and the minimum function as risk criteria to ensure the robustness of the objective function. This model is designed to minimize the weighted expected value, WVaR, and the minimum progress function, thereby promoting the 3R and sustainability framework to tackle budget fluctuations and enhance project viability. The case study revolves around the construction of national projects in Iran. Ultimately, the project's required budget was allocated within the budgetary constraints. Sensitivity analysis found that the integration of 3R and sustainability led to a 13.5 % reduction in the progress function compared to scenarios without these principles. Furthermore, increasing the conservatism coefficient to 20 % decreased the progress function to −0.58 %. Reducing the resiliency coefficient had an adverse effect by disrupting the budget allocation process. The computational time is increased gradually with the escalation of problem complexity, while the progress function decreases due to the increased number of projects. The findings demonstrate that using an exponential function promotes risk aversion, whereas a sine function encourages risk-seeking behaviour within this research context.

Inventory management challenges are optimizing inventory levels, minimizing stockouts, and streamlining the supply chain process for the vendor and the customer. The study tries to improve these challenges by proposing a new Viable Supply Chain (VSC) incorporating Vendor-Managed-Inventory (VMI) with a Consignment Stock (SC) policy for managing inventory between SC components. These strategies access the inventory level of the customer in the vendor, and if the items are sold, the customer pays the vendor for the inventory that was sold. The Robust Stochastic Optimization (RSO) with Conditional Value at Risk (CVaR) as risk criteria is utilized to solve the model. The objective function of this model combines the expected value, maximum, and CVaR of cost. To promote viability against disruption, sustainability requirements such as CO2 emissions and energy consumption are considered. An agile approach that includes a learning factor is suggested. In addition, a resiliency strategy by addressing order disruption requirements is proposed. The case study of this research is a small healthcare industry that prepares drug products. It is one of the largest industries with high sales and added value. The results show that the inclusion of VMI and CS in the main problem-solving approach resulted in a 14.8 % cost reduction compared to the scenario where VMI and CS were not considered. Finally, sensitivity analysis is performed on CVaR confidence, conservatism coefficient, learning rate, agility rate and scale of the main problem.

A common analysis method of soil-structure systems in seismic design procedures such as FEMA-440 is to replace the entire soil-structure system by a fixed-base oscillator with an equivalent fundamental period and damping ratio to consider inertial effect of soil-structure interaction. It is generally believed by researchers that ignoring kinematic effect of soil-structure interaction is conservative to determine response of structures and FEMA-440 supports this idea by defining a reduction factor applying to elastic response spectra. Also, the improvements of nonlinear static procedures in FEMA-440 are achieved for fixed-base structures and the soil effects are not perfectly obtained in coefficients and relations of these procedures. Thus, it seems necessary to assess the accuracy of proposed procedures of FEMA-440 to include soil-structure interaction. In this paper, the accuracy of equivalent replacement oscillator and nonlinear static Procedures of Equivalent Linearization and Coefficient methods, defined in FEMA-440, to analyze soil-structure systems with surface and embedded foundations are evaluated. Both kinematic and inertial effects of soil-structure interaction are investigated by conducting a parametric study using 20 ground motions recorded on soft soil site E, on which the more SSI effects are probable. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to design and explain the development model of future managers based on talent management and personality types with the grounded theory approach in the headquarters of the National Social Security Organization.Method: This research was conducted with a qualitative-inductive approach and Strauss-Corbin's grounded theory method. The research tool was a semi-structured interview. Using the grounded theory method, the data obtained from interviews with 12 elites and qualified specialists of the Social Security Organization were analyzed in three open, axial, and selective coding stages.Findings: 19 general categories in the form of a paradigm model in which these factors include causal conditions (individual factors, organizational factors, lack of proper selection, knowledge and skills of employees), central phenomenon (future managers based on talent management and personality types), contextual conditions (Organizational context, Talent Selection, Talent utilization), intervening conditions (psychological (individual) factors, Individual factors, Management factors), and strategies (Talent sourcing, Empowerment of managers and employees, Proportion of job and employment, Succession, Foresight and Cognitive Strategy) and Consequences (Organizational results, Public satisfaction, Futurization).Conclusion: Conclusion: Recent developments in the field of human resources have made this field doubly important. Organizations try to employ the most specialized people at management levels, and therefore talent management, as a key king, examines the types of situations involved in this field. Proper use of talents leads to success and puts the organization on the right track.

Today, most supply chains are moving towards green business with a greater focus on environmental protection as a competitive advantage. Among them, the design of a three-stage green supply chain with optimal allocation, a multiple supply chain that includes supplier (first stage), manufacturer (second stage) and distributor (third stage), based on maximum efficiency and considering the internal processes and products between these three levels, can be of special importance; because, it will increase the economic and environmental performance of the supply chain. One of the methods used to evaluate efficiency in Green Supply Chain Management (GSCM) is Data Envelopment Analysis (DEA). Therefore, performance evaluation is vital for companies to improve the effectiveness and efficiency of the supply chain. In this study, using the three-stage approach of DEA, the data collected in 2020 from 9 Selected home appliance companies have been analyzed. The results show that company 1 has the best efficiency and the greenest supply chain and company 7 has the worst value of efficiency, which makes it necessary to pay more attention to low performance companies. In order to show the capability of the proposed model, the developed model was compared with its equivalent base model, and companies 1 and 2 were identified as inefficient in the proposed model, but identified as efficient in the base model. Given that the efficiency score in the proposed model is always lower than the base model, so the accuracy of the developed model can be concluded.

Digital transformation, which has always been important as a fundamental and strategic action in organizations, has become more important in recent years following the outbreak of coronavirus and the pressures of the coronavirus epidemic have accelerated the efforts of organizations to create digital transformation. The purpose of this study is to design an organizational performance model based on the digital status of the organization in the Corona era with the data foundation approach in the Ministry of Silence. This research was conducted with a qualitative-inductive approach and the method of Strauss-Corbin contextual theory. The research tool (data collection) was a semi-structured interview. Using the grounded theory method, the data obtained from interviews with 27 elites and qualified specialists of the Ministry of Silence were analyzed in three stages of open, axial, and selective coding. 18 general categories in the form of a paradigm model in which these factors include causal conditions (individual factors, organizational factors, technological factors, and environmental factors) central phenomenon (digital status of the organization), underlying conditions (digital context, management context, individual context, technology context), conditions Intervener (individual factors, cultural factors, and organizational factors) and strategies (individual strategy, managerial strategy, and organizational strategy) and consequences (individual results, organizational results, and social results).

Change in modal strain energy is one of the indicators used to detect damage in structures. However, in structures with high degrees of freedom, such as double-layer grids, this method requires a relatively large number of mode shapes which in practice is difficult to determine. Therefore, it is necessary to reduce the number of required mode shapes. In this study, a damage detection technique based on modal strain energy and Dempster-Shafer evidence theory is presented for locating damage in double layer grids using only a few number of mode shapes. First, by calculating mode shapes of the grid in undamaged and damaged states, the modal strain energy based index for each mode shape is determined. Then, the results obtained from separate mode shapes are combined using Dempster-Shafer theory to achieve better results. In order to investigate the effect of noise on damage detection, 3% random noise is added to mode shapes. To demonstrate the performance of the proposed method, different single and multiple damage cases with different damage intensities are considered. Numerical results show that using 5 mode shapes, the presented technique can detect up to 3 damaged elements with different damage intensities in different parts of the grid with good accuracy (probability of 92.3%). Considering the fact that the classical modal strain energy method fails to distinguish even 1 damaged element in the double layer grid, the result shows significant improvement.

The present research is the first research on Fama and French Factor model analysis using wavelet analysis approach in Tehran Stock Exchange. However, in the case of the three-factor model Rostami et al. (1396) in a research entitled "Multi-scale pricing model with wavelet analysis approach and three Fama-French factors and non-liquidity in Tehran Stock Exchange", a three-factor Fama and French model with a three-factor approach Wavelet decomposition. The relationship between stock returns with beta, book value to market value and firm size in the medium term are significant. The relationship between stock returns and size in the short run is significant.The regression analysis of the time scale of the Fama and French model of the five-factor model using the wavelet analysis in MATLAB software shows that in the short run (2-4 months), variables of size, risk and profitability have a positive and significant effect on returns. . In the medium term (4 to 8 quarterly periods), size, risk, value, and long-term (8 to 16 quarterly periods), risk and investment have a positive and significant effect on returns.Wavelet analysis and Famafrnch model analysis at different time scales show that investors in different time horizons should consider different factors in shaping their expectations of a portfolio. The proposed methodology suggests that investors choose investment opportunities with dynamic portfolio management strategies and take multi-dimensional risk and returns.

In large civil engineering structures, the output-only modal identification is the most applicable technique for estimating the modal parameters such as damping. However, due to no measurement and control of excitation force, the identified parameters obtained by output-only technique have more uncertainty than those derived from the input-output technique. Given the different nature and uncertainties of the two modal identification techniques, in the present study, the damping related to the first 12 modes of a double-layer grid developed from the ball joint system were identified via the two techniques and compared with each other. For this purpose, a double-layer grid was constructed by pipes and balls with free-free boundary conditions provided for both input-output and output-only experiments. Exciting the grid, its acceleration response was measured at appropriate degrees of freedom. Then, by using these data and performing modal analysis, involving four different methods of input-output and five different methods of output-only, the natural frequencies and damping ratios of the desired modes were extracted. The results indicated that despite the good agreement between the modal damping of the grid, as identified by different methods of input-output together and by different methods of output-only together, the results of input-output and output-only methods were different with each other. The damping values through the input-output modal identification methods were on average 65% higher than the corresponding values of the output-only modal identification methods.

Due to markets growth, financial instruments, complexity of financial markets and advancements in category of investments, investors and workers at financial market are in need of tools, methods and models which help them in selecting the most appropriate portfolio. Due to this need, various theories, models and methods were suggested to price the financial assets and calculate the rate of stock returns and they are developing everyday. One of these models is the three factor model of Fama and French which has been under the focus of researchers during the last two decades. Five factor model of Fama and French has the factors of three model factor of Fama and French and it also includes profitability factor and investing factor. Recently (2014), the two researcher developed their previous model and suggested a new model.The aim of this study is to evaluate and explain the five factor model of Fama and French stocks returns. In order to achieve the goal of this study, 5 hypotheses have been considered. A systematic elimination method has been used to sample and the total of 182 companies have been selected in Tehran stock exchange between 1387 to 1393. To examine the hypotheses, regression panel has been used. The results of the studies shows that market factors, firm size and profitability have positive and meaningful effect on stock returns, but the factor of value (ratio of B/M) has a significant negative impact on returns.

Background and purpose: Health inspectors are faced with high levels of workload and stress. There is lack of evidence on the relationship between job burnout and the quality of working life in this group. So, research on this issue is highly needed. Materials and methods: This cross-sectional descriptive-analytical study was conducted on census based population (n=245 health inspectors) in Golestan University of Medical Sciences. Demographic information were collected and the Quality of Work Life (QWL) scale and Maslach Burnout Inventory (MBI) were also used. Data analysis was done in SPSS V18 applying Pearson's correlation coefficient and backward LR logistics regression to investigate the relationship between the quality of work life and job burnout and predicting the factors affecting job burnout, respectively. Results: Total QWL score and MBI score were 70.40±13.42 and 42.64±20.24, respectively. According to Pearson's correlation coefficient, there were significant inverse correlations between all dimensions of QWL and job burnout (P

Changes in modal strain energy of elements before and after damage is a robust damage detection index. However, in structures like double layer grids which have large number of elements, this method has some problems. First, In large structures this method needs more mode shapes to detect damage through modal strain energy method which in practice is difficult to determine. Second, this method introduce some healthy elements as damaged element. To overcome these problems, in this paper a two stage damage detection technique based on modal strain energy method is presented for detecting damage in double layer grids. First, the Modal Strain Energy Based Index (MSEBI) for each mode shape is determined. Then a data fusion technique based on Bayesian theory is used to combine MSEBI values obtained from each mode shape to find damaged elements. Then Charged System Search (CSS) optimization method which is a powerful optimization method is employed to optimize an objective function based on natural frequency to determine damage severity of damaged elements. To demonstrate the performance of the proposed method, a large double layer grid with 1536 elements and different single and multiple damage cases is considered. Numerical results show that the proposed method can successfully find damaged elements and their severities using only few first numbers of mode shapes and frequencies.

Output-only structural identification is conducted by output data of the structure. These data usually include structural response together with some noise. Success of output-only methods in determining the vibration parameters of a structure depends on the signal to noise ratio (SNR) of the output data. In this paper, the vibration parameters (Natural frequency and Mode shape) of a contilever beam have been obtained using output data which have different signal to noise ratios. The vibration parameters of the beam were determined using modal analysis of finite element model and considered as reference parameters. Then, appropriate input was applied to the beam and the acceleration signal was obtained. To generate noisy data, noise with different powers compared to signal powers were added to acceleration signal. The modal parameters of the beam were obtained using two output-only methods, Peak Picking (PP) and Stochastic Subspace Identification (SSI). The vibration parameters having signal-to-noise ratios greater than 25 (lower noise level) for all considered modes were identified properly. At a signal-to-noise ratio of 0.25 to 25 (higher noise level), it was not possible to identify the modal parameters of the first mode of the beam, but the parameters of the higher modes were identified with good accuracy.

Background: Today, a safety and conscious work environment in various organizations and industries can be mentioned as a long-term competitive advantage, the improvement of which leads to the prevention of accidents for different types of organizations in different countries. A safety-conscious work environment enables organizations to identify signs of reduced security before accidental incidents occur. This active performance in the gas company is very important.Organizations are active in ensuring compliance with safety and conscious work environment requirements, and employees can report any concerns without fear. On the other hand, one of the important and decisive requirements in safety and even environmental management systems is the identification of factors affecting the establishment of the immune system. The reason for including this requirement in these standards is the importance of reducing the consequences of the accident. In recent years, many efforts have been made to identify the causes of accidents in various industries, especially the oil and gas industry. It has been believed that most accidents are caused by human error, and it is easy to conclude that such error is due to carelessness or inefficiency in doing things, but this argument is not true. People who study accidents have found that humans are the only link in the chain that causes an accident. It is not possible to prevent accidents by changing people, it is only possible to prevent them by identifying the causes of an accident. A safety and conscious work environment allows highly reputable organizations to be active in the safety of the organization and enables employees to report any concerns easily and without fear of retaliation. On the other hand, the companychr('39')s failure to implement projects may incur human, economic, and environmental costs, and enable a safety and conscious work environment for organizations to identify signs of declining security before accidental events occur. A safe and informed work environment means that employees can freely express their security concerns without fear of retaliation, harassment or discrimination. SCWE policies should allow employees to manage both safety and security concerns without fear of punishment. In large, high-risk companies, including the gas company, a safe work environment may help prevent accidents. These events can hurt people, the economy and the environmental consequences. However, these incidents are rare. However, failure in system components (such as people, devices, trends) can hurt the company in unpredictable ways. In this regard, Chaharmahal and Bakhtiari Gas Company intends to take appropriate measures to improve the safety of employees and the companychr('39')s environment. One of the measures proposed to the officials of this company is to take measures to create a culture of safety and awareness. In this case, the officials of this company should implement programs in various aspects to create a proper culture in employees, safety quality and improve the health of the company. Recently, little research has been done on the conscious work environment. The concept of SCWE has attracted a lot of attention among experts because SCWE allows organizations to anticipate potential problems and prevent accidents. Therefore, the aim of this research is to provide a safety-conscious work environment model in Chaharmahal and Bakhtiari province Gas Company. Methods: In previous studies, many safety models have been proposed. In this study, the aim is to develop previous models and provide a new model safely and consciously, and because the purpose of this study is to develop science and help managers to use SCWE. This research is a developmental-applied study that has been performed as a sequential mix 10. experts of Chaharmahal and Bakhtiari Gas Company using snowball sampling method (in this method, the researcher first goes to the expert he knows. He introduces another expert after giving information, and this method continues until theoretical saturation is achieved. In the qualitative section, with the help of qualitative thematic analysis method, first reviewing the research background, semi-structured interview questions on safety and conscious work environment were developed and in several sessions with researchers and experts in this field, the accuracy of content and their adequacy to identify effective and constituent factors were examined. In the next step, with the identification of experts, interview sessions were held with ten experts. At this stage, coding and description were done. And was held with two reports in the interpretive coding stage in order to explain the concepts of the interview. The reliability study was performed using the method of percentage agreement between the two coders (researchers), and the figure of 80% of the agreement expressed the reliability of the qualitative section. In the last step, after organizing and organizing the data, they analyzed it and the process of extracting the meaning of the data by coding method began. To encode the interviews, the researchers first returned the audio files to the text, then used the content analysis method (induction) to identify the codes in an open and unrestricted manner. Interpretive structural modeling was used in the communication component. Structural interpretive modeling is a suitable technical technique for analyzing the effect of one element on other elements. Results: Based on interviews with experts, 24 interpretive themes were obtained and using coding and considering the nature of these 24 sub-categories and a detailed study of the relationships between them, the components were classified into 7 comprehensive themes. The results of the thematic analysis of the seven components for a safe and informed environment of work included the commitment of corporate executives, training, freedom and employee self-confidence, comprehensive strategy and cooperation, HSE planning, compliance and risk management . Based on the results of ISM, the first level employees feel the feeling of freedom and self-confidence. After identifying the first level variables, these variables are removed and the set of inputs and outputs is calculated without considering the first level variables. According to the output of the second level determination calculations, the training variable is the second level variable. According to the output of the third level determination calculations in the ISM hierarchy, comprehensive strategy variables and cooperation and risk management of the third level variables and based on the new inputs and outputs of HSE programming variable were selected as the fourth level elements. Finally, the commitment variable of managers is considered as the sixth level variable. With the aid of interpretive structural modeling method, the variable of management commitment, such as the model rock, acts as the factor of freedom and self-confidence of the top managers of the model. Employeeschr('39') feelings of freedom and self-confidence and the component of training are also less influential, but they are more dependent on other components. Components of risk management and comprehensive strategy and collaboration are located in the link area, which has high penetration power and high dependence. The components of commitment of managers, compliance with the rules and planning of a safe and conscious work environment are in the area of influence. These components have high penetration power with minimal dependence. Conclusion: The commitment of senior management is more important than other variables, and to evaluate it, we must start from this factor and reach other factors. Making strategic decisions about safety culture depends on the commitment of senior management. If senior management is committed to itself and its organization, it can help the organization to implement and develop SCWE and provide the company with many strategic and tactical benefit. As it turns out, after the commitment of management, compliance with the rules is more effective. By following the rules and health requirements, you can expect HSE planning in the organization. This management system takes steps to sustainably develop, reduce costs, and increase productivity by preventing injuries and health events, safety, and the environment, and by taking into account the health and safety of employees and others affected by the organizationchr('39')s ongoing activities. The success of this system requires the existence of a comprehensive strategy and the participation of all employees in the implementation of health, safety and environmental requirements. On the other hand, risk management is one of the basic components in preventing accidents and unsafe accidents. And with the right training, identifying risks and controlling risks to employees and managers can create a sense of confidence and freedom in employees. The commitment of the gas company managers to promote SCWE culture is essential, and to achieve this goal, it is possible to educate and promote the concept of a safe and informed wor6king environment for managers and employees. Given the importance of the gas industry in the countrychr('39')s economy and peoplechr('39')s lives, as well as the impact of safety culture on the safety of employees, designing a safe and informed model in the organization purposefully and emphasizing safety awareness can be a factor to intensify and Accelerate the promotion of a conscious safety culture in the organization. Organizational cultures should be encouraged in organizations. In addition, managers need to strengthen policies and communication practices that consciously support a safe work environment. The results obtained in this study only belong to a small representative of the countrychr('39')s industries, so in generalizing the results to all industries in the country, precautions must be taken. In future research, researchers will use dynamic modeling that can analyze causal relationships and safety dynamics over time.

Technical analysis is constituted as an approach in the market analysis which is based on the study of pricing behavior and shares size in the past and price determination and its procedure in the future. Algorithmic transactions are growing rapidly in order to automate business strategies, given the arrival of computer-based technologies and the rapid processing of bulky information. Trading systems combine input information and ultimately identify the time of purchase and sale by forming one signal. In this paper, the training system is a kind of fuzzy inference system that combines fuzzified RSI and SO signals from technical analysis. The system’s trade rules database (selling, buying, and holding) would be calculated based on an optimization process using PSO. This optimization process should be repeated at certain intervals to keep the system up to date. This process is called the corrective property of systems. The findings on the overall index in the period 2001/3/21-2019/3/20 indicate that the system having optimized training on training data has an average daily return of /0027, risk-taking of /0065 and the daily sharp ratio of /42. Concerning the index of return and sharp ratio, the findings reveal that the system outperforms the signals and the market performance.

Abstract: The upward growth of steel industry has led to an increase in demand for raw materials and the release of about 7% of global greenhouse gases (An et al., 2018; Griffin and Hammond, 2019). Blast furnace (BF) is the most essential section of a steel company (Liu et al., 2016). Costs of production in steel companies are contributive to the competitiveness of such plants (Zhang et al., 2011). Due to the shortage of domestic lump and concerns about CO2 emission, Iranian steel industry has encountered serious challenges of supplying ferrous raw materials and coke for blast furnaces, while the overproduced direct reduced iron (DRI) and the vast sources of domestic natural gas and pulverized coal have made it possible to replace coke with these sources of energy and using DRI as ferrous raw material in the blast furnaces. High differences in the price of coke with natural gas and pulverized coal along with big price gap between DRI and lump, the influence of replacing complexity on the cost of ferrous raw materials, coke, and energy consumption, BF productivity, technical constraints, and carbon dioxide emissions level are the main reasons for conducting this research. Design/methodology/approach: A non-linear optimization model, extracted from thermodynamic equations, process relations, and mass and energy balances, has been applied in this study. This model can be applied as a decision support system for purchasing and supplying coke-energy, ferrous burden materials, and examining the effect of consuming different raw materials on the CO2 emission and evaluating the production profit. Findings: Results indicated that this model can decrease CO2 emission and is highly effective in gaining company benefits. Based on the research sensitivity analysis it was found that despite the advantages of the model, as long as there are no tough restrictions on CO2 emission like in Japan and in the developed European countries, and there is subsidized domestic lump charging DRI as BF burden materials, it is not economic. As a result, it was concluded that available ferrous raw materials options for Iranian blast furnaces are only lump, sinter and pellet. Research limitations/implications: BF thermal reserve zone is assumed 1200k, which may vary from 1100 K up to 1300 K in practice; hot metal and slag temperatures are assumed fixed; chemical elements distribution is assumed fixed; and the state of gas rising from the bottom segment into the up segment of BF is ignored. Practical implications: The proposed model was implemented in MATLAB and validated using the data of Esfahan Steel Company. A comparison between the model results and the experience-based results for supplying ferrous materials blending indicated a good compromise between the model and real situation, and it leads to an increase in production benefit around 16% for ferrous raw material and 19% for energy when using the model to purchase them. Another advantage of this model is the ability of prediction of raw materials which affects production parameters. In this regard, the effect of DRI on the CO2 emission, energy consumption and the benefit were studied and validated. Originality/value: Some of the innovation aspects of this study include: i) compared to available studies, optimal decision making on the supply and replacement of raw materials and energy, together with new constraints, were analyzed; ii) applying scrap and direct reduction iron (DRI) as environmental friendly ferrous raw materials for Iranian blast furnaces became possible, which contributed to a decrease in energy consumption; iii) the coke consumption rate in a BF as a function of the blending of ferrous burden materials and other production variables was assumed to change; and iv) for the first time in this study, the simultaneous consumption of carbon-bearing materials such as pulverized coal, natural gas, oil and coke were modeled. References Liu, X., Chen, L., Feng, H., Qin, X. and Sun, F. (2016). “Constructal design of a blast furnace iron-making process based on multi-objective optimization”. Energy, 109(16), 137-151. Griffin, P.W. and Hammond, G.P. (2019). “Analysis of the potential for energy demand and carbon emissions reduction in the iron and steel sector”. Energy Procedia, 158(3), 3915-3922. An, R., Yu, B., Li, R. and Wei, Y.M. (2018). “Potential of energy savings and CO 2 emission reduction in China’s iron and steel industry”. Applied Energy, 226(18), 862-880. Zhang, R., Lu, J. and Zhang, G. (2011). “A knowledge-based multi-role decision support system for ore blending cost optimization of blast furnaces”. European Journal of Operational Research, 215(1), 194-203.

Today, organizations are under tremendous pressure to continuously enhance their capabilities to create value for customers and improve the effectiveness of equipment. Without the proper equipment organization will face major challenges in competition and customer satisfaction. Inappropriate performance of equipment is a phenomenon that any manufacturing organization faces with it. The strategy is selected against this phenomenon, depends on several factors. This issue becomes more important when the production line is continuous. In electricity company providers because of supplying strategic product issue is more complex. In this study, tried to determine the factors affecting the conditions in relation inappropriate performance of equipment to define this phenomenon. Therefor, using a three-stage approach of Grounded theory, with inductive method to study the phenomenon of improper performance of equipment has been studied and with gathering the experts opinion this industry and analyzing relevant data in five categories and 24 subcategories and 90 characteristic this phenomenon has been described and then how to choose appropriate strategies for different conditions explained.

At the present time, it is impossible to imagine manufacturing organizations without running maintenance systems. Maintenance is a system that supports the core processes. Therefore, a maintenance system is essential for manufacturing organizations in order to maintain competitiveness. As yet many studies have been done on maintenance systems but there is almost no study comprehensively examining various aspects of the system. In this study, defining the attributes of maintenance phenomenon, dimensions and components of maintenance system are clarified. By the use of meta-synthesis approach, previous studies are analyzed and maintenance phenomenon is categorized in five dimensions, 31 sub-dimensions, and 98 components. Finally, the effect of the specified components in 209 previous studies has been determined using Shannon entropy method. And, it has been shown that what factors or codes have received the most emphasis in each theme.

The current web evaluation models are mainly based on the technical evaluation of the site and its appearance and usability from user's perspective. In other words, the site is evaluated as an independent entity from the underlying organization that it represents. The focus of this study is on evaluation of organizations' websites based on the quality management concepts. In this way, the measured performance indicators will be used to find the deficiencies of the websites and recommend corrections. For evaluating the organization’s success in its website function, the concept of quality management is used and since evaluation and improvement are the center of attention in this model, the model is called Ev-Imp, which Ev stands for evaluation and Imp stands for improvement. Model includes four main components consist of objectives, processes, criteria and feedback. With the use of feedback tools such as quantitative and qualitative questionnaire for groups of stakeholders and service providers ,the website’s weaknesses and strengths would be identified and with analyzing the website’s weaknesses required improvement would be determined and corrective action would be done

Inventory control is one of the important issues in supply chain management. The present study deals with designing and comparing a multi-level multi-product inventory simulation model in Iran steel industries. The divergent supply chain network model is considered with several final products, several middle products and one primary product. The purpose is to minimize cost function by maintaining the minimum level of service offering for each facilitation that is measured by means of fill rate. It is tried in the proposed model to achieve a local optimal point by having a possible point and second-order localization of the target function and linear constraints around that point as well as the use of genetics algorithm. Since point estimations of the target function and fill rates are carried out with the help of Monte Carlo simulation, statistical hypothesis testing is employed to test the possibility and improve the responses. After validation is fulfilled, the model is implemented in a three-level network via the information of Mobarakeh Steel Company. Given that linear localization is a specific state of second-order localization, it can be expected with more confidence that the achieved point in this model is better than the linear localization state.

Background: For improving the quality of endodontic performance of practitioners in clinical practice, their basic, preclinical performance and knowledge must be taken into consideration. This study aimed to radiographically evaluate the technical quality of preclinical molar root canal treatments (RCTs) performed by undergraduate dental students at a dental school in Iran. Further, the effect of using Gates-Glidden (GG) drills on the final quality of RCTs was evaluated. Materials and Methods: In this retrospective cross-sectional study, 315 roots of 105 endodontically treated teeth in preclinical practice were evaluated radiographically. The analyzed quality parameters included length, taper and density of fillings, which were scored as S2 (adequate standard), the S1 (slight deviation), or S0 (considerable deviation). For all the parameters, acceptable, moderate and poor fillings received total scores of 6, 3-5 and 0-2, respectively. There were two groups of students: One group had used only K-files, and the other had used K-files along with GG drills. The quality of RCTs between these groups was evaluated using the aforementioned scoring protocol. The results were analyzed using Chi-square, Mann-Whitney and Fisher′s exact tests (α = 0.05). Results: Under-fillings (P = 0.001) and under-shapings (P = 0.007) occurred mostly in mandibular root fillings. A lower density was found in maxillary fillings (P < 0.001). No relationship was observed between the technique used (irrespective of GG drills usage) and length (P = 0.499) and taper of fillings (P = 0.238). The roots instrumented with GG drills had a higher filling density (P = 0.004). The quality mean score of RCTs was improved when GG drills were used (P = 0.008). Conclusion: The technical quality of preclinical molar RCTs performed by undergraduate dental students was considered acceptable in 35.6% of the cases. When GG drills were used along with K-files, the technical quality of RCTs was enhanced.

Background: One of the serious problems that opioid addicted people are facing is repeated withdrawal syndrome that is accompanying with a significant stress load for addicts. Therefore, the aim of this study was to evaluate the effects of repeated withdrawal on spatial learning, memory and serum cortisol levels in morphine-dependent mice. Materials and Methods: Male NMRI mice received morphine as daily increasing doses for 3 days. After that, the mice underwent one time or repeated spontaneous or pharmacologic (naloxone-precipitated) withdrawal. Then spatial learning and memory were investigated by morris water maze test, and at the end trunk blood samples were collected for measurement of serum cortisol levels. Results: The results showed that only repeated spontaneous withdrawal significantly increases escape latency ( P < 0.05), and in other models of withdrawal, spatial learning and memory were intact. The results of probe trial were intact in all groups. Radioimmunoassay showed that serum cortisol levels were increased significantly in all models of withdrawal ( P < 0.05 and P < 0.01) except the repeated spontaneous withdrawal. Conclusion: The results showed that short periods of withdrawal syndrome can increase serum cortisol levels; however they do not affect spatial learning and memory. Nevertheless, repeated spontaneous withdrawal can make learning slow.