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Introduction: Microperforated panels (MPPs), often considered as potential replacements for fiber absorbers, have a significant limitation in their absorption bandwidth, particularly around the natural frequency. This study aims to address this challenge by focusing on the optimization and modeling of sound absorption in a manufactured MPP. Material and Methods: The study employed Response Surface Methodology (RSM) with a Central Composite Design (CCD) approach using Design Expert software to determine the average normal absorption coefficient within the frequency range of 125 to 2500 Hz. Numerical simulations using the Finite Element Method (FEM) were conducted to validate the RSM findings. An MPP absorber was then designed, manufactured, and evaluated for its normal absorption coefficient using an impedance tube. Additionally, a theoretical Equivalent Circuit Model (ECM) was utilized to predict the normal absorption coefficient for the manufactured MPP. Results: The optimization process revealed that setting the hole diameter to 0.3 mm, the percentage of perforation to 2.5%, and the air cavity depth behind the panel to 25 mm resulted in maximum absorption within the specified frequency range. Under these optimized conditions, the average absorption coefficient closely aligned with the predictions generated by RSM across numerical, theoretical, and laboratory assessments, demonstrating a 13.8% improvement compared to non-optimized MPPs. Conclusion: This study demonstrates the effectiveness of using RSM to optimize the parameters affecting MPP performance. The substantial correlation between the FEM numerical model, ECM theory model, and impedance tube results positions these models as both cost-effective and reliable alternatives to conventional laboratory methods. The consistency of these models with the experimental outcomes validates their potential for practical applications.

Power semiconductor devices are the most important components in power electronics applications. They are also the most fragile components of electronic circuits. A power semiconductor device's switching performance and protection depend on the gate drive circuit specifications. Therefore, choosing an appropriate gate-driver and designing its corresponding circuits is necessary. This paper is a technical review of the proper design of gate drivers for silicon power switches (like Si IGBT and Si MOSFET) in industrial power electronics applications. In this paper first conducts an overview of the main specifications of gate drivers for industrial power electronics applications. Then, concerning the protective role that a gate-driver can provide, crucial points of an effective design are discussed. Finally, a circuit is proposed to test the gate driver's short-circuit protection. The circuit is experimentally evaluated for three gate drives, and the results are discussed. A practical comparison of the protection performance of commercial gate drives ACPL-330J, ACPL331, and PC929 is also conducted.

Introduction: Disturbing noise can cause physical and mental illnesses among workers; for this reason, it is necessary to restrain it, especially in workplaces. Using sound-absorbing materials with suitable acoustic properties has been a growing trend in mitigating noise. This study aimed to improve the acoustic properties of polyurethane foam (PUF) as a sound absorber. Material and Methods: In the present study, PUF was synthesized with different percentages of clay nanoparticles (0 -1.2 wt.%), and then the Sound Absorption Coefficient (SAC) of the synthesized PUF was measured by the acoustic impedance tube in the frequency range of 63 to 6400 Hz according to the ISIRI 9803 standard without an air gap behind the sample. The morphology of the foam was also investigated by Scanning Electron Microscope (SEM). Results: The results showed that the addition of clay nanoparticles to PUF improved the sound absorption behavior of the samples, and the best sound absorption behavior was for PUF with 1.2% weight of nanoparticles at low frequencies (500-2600 Hz). This increase in the absorption coefficient can be due to the increase in the number and smaller size of the pores with the increase in the amount of nanoparticles in PUF. Conclusion: This study illustrates that the incorporation of clay nanoparticles into PUF at varying percentages results in an enhanced absorption coefficient. The presence of clay nanoparticles leads to a reduction in cell size and an increase in the number of pores, consequently enhancing surface friction. The absorption coefficient was observed to increase with the growing concentration of clay nanoparticles in PUF.

Compressors are a significant source of noise in various industries. Silencers can be utilized to mitigate this noise. This study aims to design and construct an expansion silencer that can effectively reduce the pulsating noise produced by a reciprocating compressor. This study employed a model-experimental approach to investigate the performance of four different sizes of expansion silencers in controlling the pulsating noise in the suction part of the compressor. Initially, the silencers' sound transmission loss and pressure loss were simulated using the finite element method with COMSOL software. Subsequently, the sound transmission loss of the silencers was measured according to the E261109 standard using an impedance tube. Finally, the pressure loss of the silencers was measured using a Pitot tube upstream and downstream of the silencer at various flow rates. The results of the modeling showed that increasing the diameter of the silencer leads to an increase in transmission loss at all frequencies. Additionally, raising the length of the silencer only increased the number of sound transmission loss peaks in the frequency bandwidth without significant change in sound transmission loss. Furthermore, the results of the experimental measurements with an impedance tube revealed that increasing the diameter results in increased transmission loss, while increasing the silencer length leads to an increase in the number of transmission loss peaks without altering the transmission loss. Moreover, the modeling and experimental pressure loss results indicated that increasing the diameter of the expansion chamber causes an increase in pressure loss, while increasing the length of the expansion chamber results in a minor change in pressure loss. Finally, the research results showed relatively good agreement between modeling and experimental outcomes.

Periodic sound reduction at some frequencies and high pressure loss could be considered as the disadvantages of simple expansion silencers. Generally, reactive elements are applied in silencers to optimize their acoustic and aerodynamic performance. In this paper, we were going to investigate the combined and independent effects of reactive elements, baffle and extended tubes at the inlet and outlet of simple expansion silencer, on the acoustic performance and pressure loss of simple expansion silencer. Firstly, simple expansion silencer dimensions were determined based on theoretical calculations to attenuate the noise by 10 dB. Secondly, the simulation was performed using COMSOL acoustical module software based on finite element method to predict silencer sound transmission loss and pressure loss, respectively, before and after adding reactive elements. Then, according to ISO7235, ISO3744 and ISO3746 standards noise insertion loss of various silencers under study was measured in a free field and in the following that silencers pressure loss evaluated. Finally, the predicted results with the software were compared with the experimental ones. The addition of the extended tubes increased the transmission loss and insertion loss at low and medium frequencies and mitigated the pressure loss of the silencer compared to the simple expansion silencer. The baffle increased the transmission loss curve in the medium frequencies compared to the simple expansion silencer. The combination of baffle and extended tube elements caused an extraordinary increase in insertion loss and transmission loss at the medium frequencies and a decrease in pressure loss. It could be concluded from the present study that using extended tube might be probably the best choice to reduce pressure loss and increase the acoustic performance of simple expansion silencer at low and medium frequencies and what's more is that the best acoustic performance in medium frequencies can be achieved by using a combination of baffle and extended tube.

Background: Awkward posture during work is one of the most critical risk factors for musculoskeletal disorders. A laptop desk fitting with users’ body dimensions plays a crucial role in maintaining proper posture and reducing musculoskeletal disorders. This study aimed to redesign and fabricate a folding ergonomic laptop desk for college students.Methods: In this experimental applied study, two hundred and seven college students were considered participants to design an ergonomic laptop desk and fifty students for posture evaluation. Six anthropometric dimensions were measured: height, the height of elbows in the sitting position, elbow-elbow breadth, the length and height of both knees in the cross-legged sitting posture, and the length of the elbow-fingers. Then, two best selling laptop desks were selected and the RULA method assessed laptop users’ posture. Finally, using students’ anthropometric dimensions (n=207), a new laptop desk was designed and built in 2017.Results: The height of our designed laptop desk is adjustable (range of 20-28 cm), with a variable inclination of the desk (0- 34 degrees). It is possible to shorten or lengthen desk legs (48-72 cm), and a special plate of the mouse (19×46 cm) supports both elbows on the sides of the desk. RULA method showed action level 3, which required early change in desks 1 and 2.Conclusion: Applying user›s and expert opinions, measuring users› body dimensions, and applying those dimensions in design and construction can play a significant role in improving and correcting the laptop›s desks so that it could result in suitable posture in students.

Noise is one of the most harmful factors in the work environment, which is very important to control. There are various techniques to achieve this goal. One of the most important of them is the use of noise absorbers. Absorbent materials are often used to counteract the effects of reflected noise from hard surfaces and reduce their level. This is an experimental-applied study conducted in the physical factor laboratory of the Faculty of Health. The purpose was to predict the Noise absorption rate of combined and independent absorbers under different conditions and frequencies using the new ENC (engineering noise control) software. The sound absorption determination was carried out in 5 stages, including sound frequency analysis for the source, measurement of the dominant frequency, measurement of the absorption coefficient of absorbent materials in different conditions, measurement of the limit frequency (peak frequency of noise absorption) and comparison of the software results with the findings of the impedance tube in Real conditions. The best absorption mode for combined and independent absorbents is using a 5 cm rock wool absorbent with a 2 cm thick air layer behind it without a polyurethane absorbent layer and a 10 cm wide rock wool absorbent with a 1 cm air layer behind it without polyurethane layer. A polyurethane layer on the stone wool absorber decreased the amount of noise absorption for high frequencies. The results obtained from the best absorption conditions in the ENC software were consistent with the findings from the impedance tube device in real situations. The results of this study showed that suitable and optimal conditions of sound absorption could be achieved by using the ENC software, correct design, use of suitable absorbers, changes in the physical parameters of the absorber, and the use of a combined absorber.

Purpose: One of the actual reasons for sponsorship is to attract millions to increase the number of consumers. Therefore, this article aims to study the effects of kit sponsorship for football clubs on Nike's corporate value by analyzing price trends.Methodology: In this study, price data was gathered from the date of released statements of the football clubs present in the 2019-2020 season of the Premier League. Analyzing the data was conducted by the market Technical Analysis method with three different indicators (RSI-MACD-Moving Average).Findings: The results showed that Nike faced significant changes in the price trend of its stock values. All of these three indicators show an increase in the exchanged volume of stock. The analysis explains its high potential of changing the trend.Originality: Because of these changes, other companies were interested in being a sponsor for many clubs in any sports field, and it creates a competitive atmosphere between the companies.

Background and Objective: Perforated panels are one of the most common resonant absorbers for sound control. These types of absorbers are widely used due to their adjustable mechanical properties and ease of processing. This study was conducted to investigate the acoustic properties of non-flat perforated panels in oblique angle and diffusion field using both numerical and experimental methods. Materials and Methods: To investigate the effect of surface shape on the performance of the perforated panel, three non-flat shapes were considered for the perforated panel and their absorption performance was compared with the usual shape of the perforated panel (i.e., flat) using the numerical method. Initially, the most appropriate shape was determined in terms of absorption coefficient. Afterward, the desired shape was constructed in the dimensions approved by the ISO 354 and subjected to a random incidence absorption coefficient test in the reverberation chamber. Results: The results of numerical simulation indicated that the shapes defined in this research all could improve the absorption coefficient at the middle and high frequencies. Moreover, the shape C showed a higher absorption coefficient at the lower frequencies than the flat and the two defined shapes. Based on the measurement of a random incidence absorption coefficient, the highest absorption coefficient was obtained at a frequency of 160 Hz with a value of 0.77. These conditions were implemented in a numerical environment and the random incidence absorption coefficient was calculated according to the existing relationships. Conclusion: It can be concluded that surface shape is effective in improving the absorption performance of these types of adsorbents. The comparison of numerical and laboratory results showed the acceptable agreement of these two methods and the numerical method is capable of predicting this quantity with good accuracy.

Background and aim: Microwave radiations are one of the most environmental workplace factors that exposed too many workers. In microwave spectrum, radar frequency with 1-300 GHz range have varied applications such as satellite, communications, military, Network, navigation, air-traffic Control, navigation, marine and weather. Uncontrolled occupational exposure to radar radiation caused to various disease and disorders such as oxidative stress, different kinds of cancers and other thermal and non-thermal adverse health effects. Regard to the importance of identification work related carcinogenic factors in prevention and decreasing cancer related costs and lack of similar studies, this study was conducted to systematically review the research on the risk of cancer in occupational exposure to radar radiation with frequency ranges 1 to 3000 GHz. Methods: The present systematic search was carried out based on PRISMA guidelines and comprehensive search strategy was focused from March 2017 to September 2018 and update on September 2018 in PubMed, ISI Web of Science, Scopus and Google scholar, MAGIRAN and SID databases with English and Persian articles without time limits were searched .Keywords were selected based on PICO principle and collected from MeSH database. comprehensive search were accomplishment by the following search terms : (worker OR technician OR occupation OR military OR airline OR navy OR police officer OR Weather ) AND (occupational exposure OR workplace OR long-term exposure OR exposure OR radar OR microwave OR wireless OR high frequency range OR radiofrequency OR radiation OR electromagnetic) AND (control group, cohort OR prospective OR retrospective OR follow-up OR randomized control trial OR case-control) AND (cancer OR malignant OR melanoma OR metastatic OR non-thermal effect OR biological effect OR health effect OR Adverse Effect OR risk factor OR Sarcoma OR tumor or leukemia OR neoplasm OR Carcinoma OR Hepatoma OR lymphoma OR mortality ) as single or complex terms in titles, abstracts and keywords. Then, taking into inclusion and exclusion criteria, the process of reviewing, screening and limiting the repeated and unrelated articles was carried out. In addition, manual references checking were done to retrieve the related articles. Also, any disagreements were resolved by consensus between reviewers. The inclusion criteria for selection studies were in design of case–control, cohort and randomized control trial studies, with control group and referring to the association between occupational exposure to radar radiation and all types of cancer in workers. The exclusion criteria were as follows: 1) studies without control group 2) reviews, case and field studies, 3) studies with inhumane population such as in vitro, in vivo and animal studies. 4) Studies that radar frequencies were out of considered ranges (1-300 GHz) .5) studies with other occupational or non-occupational carcinogenic risk factors (such as solvents, workplace air pollution, environmental air pollution, smoking and etc). After implementation of inclusion and exclusion criteria, data were extracted after preparation of the full text of included articles. The Results: A total of 533 studies was found. After removal of duplicated references, 272 studies were included for the title, keywords and abstract screening. Then, 219 studies were excluded since they did not meet inclusion criteria. Hence, 53 studies were selected for the eligibility assessment. At the end of selection process and after the quality assessment, 7 studies remained in the systematic review that including 3 case-control studies and 4 cohort studies with no randomized control trial study. A manual search of the reference lists added no more articles in this review. All included studies were from English language and external databases in various countries including USA, Germany, and France. In this systematic review, a study of clinical trials and Persian studies were not found. Finally, based on inclusion and exclusion criteria, 7 articles (4 cohorts and 3 case-control) were included, which were conducted during the 1950 to 2005 with 51898 sample size and range of ages 15–69 years that published from 1993 to 2016. Included studies examined relationship between occupational exposure to radar radiation and cancer strength among workers. Whole of the studies put determination of cancers and risk estimates in military workers. The great majority of included studies reported risk estimates with 95% confidence interval. Most included studies were conducted on testicular cancer (4 from 7 included studies) and brain cancer (4 from 7 included studies). In included studies, Relative risk were estimated, particularly about testicular, leukemia and brain cancers and mortality ratio in various types of cancers has been reported. The included studies reported no significant increase in mortality ratio about testicular cancer but increasing in relative risk were significant in two studies. There was also a significant increase in the relative risk of brain cancer in workers who occupationally exposed to radar radiation. Increase in mortality ratio due to brain cancer were significantly reported in two included studies. Conclusion: The current systematic review was carried out to investigate the cancer among workers with occupational exposure to radar radiation. It is noticeable that previous related studies focused on both environmental and occupational exposure in worker and public population and it clearly did not determine the relationship between occupational radar exposure and cancer risk in workplace. Whilst, our study just focused on occupational exposure to radar radiation that lead to small number of included studies. The results of this study can be useful to prepare the occupational health policies in related to radar radiation and provide some information to conduct associated meta-analysis in future studies. On the limitations of the included studies, the continuation of experimental studies on humans with control groups, and focusing on the study of cancer-causing radar radiation in occupational exposure to workers is necessary.in this line, World Health Organization propose to conduct further differences studies especially case-control studies. However, it should be mentioned that these results are yielded by a few numbers of available studies with no report in occupational dose and time exposure to radar frequency range. also, considering to some limitation such as few numbers of included studies, lack of data about exposure characterizations (exposure time, dose-response, average of exposure level) and demographic characterizations (average of age, average of experience, radar frequency range) it is better to continue further studies about this topic and future review studies include the congress publications without limitation in language. It is also suggested that other published articles in congresses also be used and the limitation in language of publications in the search process be removed. It is noticeable that, slight researches about occupational cancers in Iran were conducted in yet, such as studies in related to asbestosis, aromatic amines and chromium. Therefore, regarding the fast growing of cancer in developing countries like Iran, determination of occupational cancer risk factors could be useful to provide the cancer prevention and control program. So in this line, designing epidemiologic studies to focus on occupational cancers are very important especially about microwave and radar radiation.

Background: In both developed and developing countries, noise is regarded as the most common occupational hazard in various industries. The present study aimed to examine the effect of sound pressure level (SPL) on serum cortisol concentration in three different times during the night shift. Methods: This case–control study was conducted among 75 workers of an industrial and mining firm in 2017. The participants were assigned to one of the three groups (one control and two case groups), with an equal number of workers (25 participants) in each group. Following the ISO 9612 standard, dosimetry was adopted to evaluate equivalent SPL using a TES-1345 dosimeter. The influence of SPL on serum cortisol concentration was measured during the night shift. The serum cortisol concentration was measured using a radioimmunoassay (RIA) test in the laboratory. Repeated measure analysis of variance and linear mixed models were used with α = 0.05. Results: The results indicated a downward trend in the serum cortisol concentration of the three groups during the night shift. Both SPL and exposure time significantly affected cortisol concentration (p

Introduction: The phenomenon of suicide has been considered by experts of social sciences and psychology. Considering the issue of suicide, a precise analysis must first be carried out in a specific geographic region. Secondly, the cultural coordinates of the climate should be taken into account. The purpose of this study was to investigate the factors and methods of suicide in Ilam province. Materials and methods: The statistical population of this research included all suicide cases committed in Ilam province from 2012 to 2016. The total sample size based on the recorded cases from 2012 to 2016 was 3078 cases. Data analysis of this research was done at two levels of descriptive and responding to research questions. At the descriptive level, indicators such as frequency, percentage, cross-tables, and frequency distribution charts were used. In the answer section of the research Kruskal Wallis and Xi-Du were used. Results: There was a significant difference between the frequency of successful and unsuccessful suicides. 10.92% of suicides were successful and 89.08% were unsuccessful. Men tended to suicide more than women, but this was not statistically significant. In some age groups, suicide rates were higher than other groups, 34.7% were suicidal in the 21 to 25 age group, 30.06% in the age group of 31 and older, and 34.24% in the remaining age groups. Considering the methods, 73% of suicides have used pills over the last five years, and there was a significant relationship between the motivation of individuals and their tendency towards suicide (48.4%). Conclusion: The results of this study revealed that in committing suicide the individual, social, and psychological factors play the main roles, the results also presented the rate of being successful or unsuccessful in committing suicides, the gender of these attempters, their age range, the education level, the manner of committing, and finally their motive to commit suicide in years of 2012 to 2016.

Background and aims: Radio frequency and microwaves radiations are a part of non-ionizing electromagnetic radiation that have various applications in different work environments. Administrative measures reduce the occupational exposure with low cost and acceptable performance. This study using narrative review was conducted to investigate the recommended administrative controls that published by international organizations in order to control the occupational exposure to Radio Frequency and microwave radiations. Methods: Firstly, the international reference organizations were determined in relation to the research topic. Then, based on the PICO principle, related keywords designed. Then, all documents as a Government Document, Legal Rule or Regulation, Publication, Standard, Report, Guideline, Manual, were reviewed in English language without time limit. In addition, the search was conducted on two external databases (BING and GOOGLE). Then, the process of reviewing, screening and eliminating repeated, unrelated, and unusable resources was carried out. After preparation of the full text, the process of translation and extraction of related information conducted based on the organizations and administrative measures. In this study, experimental research, descriptive studies, analytical studies, Meta-analyzes, and systematic reviews, did not entry. Also, documents with incomplete and obscure information were also not used. Results: The results of this study showed that there are several international organizations that work up in field of occupational exposure control to radiofrequency and microwave radiation. extracted administrative measures are diverse and including the inspection, medical monitoring, employee participation, safe/standard operating procedure, compliance with standards, preventive maintenance, lock out/ tag out, safety signs and warnings, workplace monitoring, Responsibility of the employer, exposure limit, access restrictions, reducing output energy, training and distance . Conclusion: Meanwhile, exposure limits, maintenance process and access restrictions were the most recommended administrative controls. Among the international organization, the International Labor Organization (ILO) presented the most diverse and comprehensive administrative controls. It is suggested that the results of this study be used in health and safety radiation policies and as a simple guide to introduction on recommended administrative measures for managers and occupational and environmental health experts.

Background and aims: Discharging compressed air through conventional single jet nozzles or open pipes is a common jet noise in industry. This study is aimed to reduce air blow gun jet noise by designing and fabrication of multiple jet nozzle as a substitute for conventional single jet nozzles. Methods: One of the most common commercial air blow gun equipped with a conventional single jet nozzles was considered as a reference. An air Nozzle’s three dimensional model with multiple and smaller openings was designed by solid works software and the designed sketch was fabricated by a three dimensional printer. Noise measurement was made by a Cassella Cell 450 sound level meter with one octave band analyzer. Noise absorption foams were applied to mitigate noise reflection in the testing environment. Air thrust was measured using a digital scale that was placed 30 cm away from nozzle tips. Results: Multiple jet nozzle’s sound pressure level was measured significantly lower than conventional nozzle’s sound pressure level (P Value

Introduction: Using diesel generators is necessary for activities like welding in construction sites and it is often accompanied with noise pollution. The aim of this study was to evaluate noise pollution induced by diesel generators in construction activities in one of the districts of Tehran city. Material and Method: In this descriptive study, 14 construction sites were selected for the evaluation of noise pollution in Tehran, district 4. Background and diesel generators sound pressure level were measured in accordance with BS 5228(2015) and noise guidance in the area around the construction sites. Diesel generators sound pressure level at 4 points and also the audio frequency analysis, one meter away from the device was measured at a random locations around it. TES-1358, Type 2(Taiwan) sound level meter was used to measure sound pressure level and calibration was performed before and after noise measurement. The validated Noise annoyance questionnaire adopted from ISO15666 standard, completed by the residents. T test, correlation and analysis of variance was performed to analyze data using SPSS software ver. 22. Result: The mean equivalent sound level of diesel generators background noise were respectively 76 ± 4.05 dB(A) and 46.2 ± 1.09 dB(A) around the construction sites. Diesel generators noise around the construction sites was higher than the noise limit (background noise plus 5 dB)(P Value

Abstract Background and aims: Using water pump in residential buildings to provide the required water pressure is accompanied by noise pollution and the annoyance of residents. So, the purpose of this study is to reduce water pump noise pollution with designed acoustic curtains in a residential building of Qazvin city. Methods: The mean sound pressure level was measured before and after control intervention around the sound source based on ISO 9612, using the sound level meter (Casella-Cell.450). The sound level meter was calibrated using a calibrator (Cell-110/2). The frequency analysis was done in 1.1 octave band and the weighting frequency of A. Acoustical features of acoustic curtains (thickness, material and dimensions)were determined on the base of required sound transmission loss in predominant frequency. The volumetric flow of air required to decrease the temperature inside the enclosure up to 40°C to maintain a reasonable air temperature for pump performance was calculated using the energy-mass conservation law. Temperature inside the enclosure was measured with a mercuric thermometer. Results: The mean sound pressure level before and after control around the pump was measured 67 dBA and 46 dBA respectively. The required insertion loss in predominant frequency(2000 Hz) to accommodate noise limit in residential buildings was considered to be 26 dB and based on which acoustic curtain surface density was calculated between. The average sound pressure level measured after control (46dBA) with predicted sound pressure level by mathematical calculation after control (47dBA) was not significantly different. The volumetric flow rate required to maintain a temperature of 40°C inside the enclosure was calculated to be 1.2 cubic meters per minute. The temperature was measured inside the enclosure of 38°C. Conclusion: Control of noise pollution using acoustic curtains with a lower cost and weight, higher installation speed and higher sealing can be considered as one of the proper methods for enclosing noise resources. Keywords: Noise pollution, Water pump, Acoustic curtains, Noise control.

Heat stress negatively influences human health and performance, and leading to lower efficiency in daily activities. The present study sought to examine the relationship between UTCI, other heat indices (SET, PET, PMV, PPD, and WBGT), and environmental parameters. Daily data, encompassing a 12 month period in 2016 (from 6 a.m. to 9 p.m. for each day), were retrieved from the Meteorological Organization of Kerman. The data were fed into SPSS 20, followed by conducting Pearson product moment correlation and linear regression to find the association between UTCI and other heat indices/environmental parameters. Excel 2016 was also utilized to draw the relevant diagrams. Significant correlations were detected between UTCI and other heat indices (SET, PET, PMV, and WBGT). UTCI also was measurably correlated with environmental parameters like dry temperature (P

Water saturation determination in core laboratory is known as a cost and time consuming labor. Hitherto, many scientists attempted to estimate accurately water saturation from well-logging data which has a continuous record without losing information. Therefore, various model were introduced to relate reservoir properties and water saturation. Since carbonate reservoir is very heterogeneous in shape and size of pore throat, the relation between water saturation and other carbonates reservoir properties is very complex, and causes considerable overall errors in water saturation calculation. By increasing the usage and improvement of soft computing methods in engineering problems, petroleum engineers have been attended them to measure the petrophysical properties of the reservoir. In this study, a radial basis function neural network (RBFNN) improved by genetic algorithm has been employed to estimate formation water saturation by using conventional well-logging data. The used logging and core data have been gathered from a carbonated formation from one of oilfield located in south-west Iran, and finally their results of the proposed model were compared with the core analysis results. By checking the testing data from another well, it showed this method had a 0.027 for mean square errors and its correlation coefficient is equal to 0.870. These results implied on high accuracy of this model for oil saturation degree estimation. While the common methods like Archie, had a 0.041 mean square error and 0.720 of the correlation coefficient, which indicate a high ability of RBF model than the other usual empirical methods.

Today continuation of economic activities requires access to timely and adequate financial resources to provide working capital for enterprises, and any decision in this area has a considerable effect on the operational efficiency of the business unit and will lead to changes in the value of the company and ultimately shareholders' wealth. In current conditions, because of the volume of outstanding debts of banks, and consequently, the lack of adequate capacity to respond to the increasing demand for loans, the access to financing is more difficult, leading to undesirable and inappropriate management of working capital and companies' loss of their competitive deals. Accordingly, one of the requirements of enterprises for improving the business environment is the effectiveness in providing working capital through the development of methods to achieve short-term funding from the capital market. In this paper, by using a descriptive analytical method with fiqh-based approach and considering the requirements of sharia and the country's laws, efforts have been made to develop a model for the issuance of securities that lead to efficient working capital of firms. Thus, according to the research carried out in our country and experiences gained in the field of securities, Sukuk Al Dayn based on accounts receivable is recommended as a new model for an efficient working capital management in Iran's financial market.

Introducing the novel technique for enhancing oil recovery from available petroleum reservoirs is one of the important issues in future energy demands. Among of all operative factors, wettability may be the foremost parameter affecting residual oil saturation in all stage of oil recovery. Although wettability alteration is one of the methods which enhance oil recovery from the petroleum reservoir. Recently, the studies which focused on this subject were more than the past and many contributions have been made on this area. The main objective of the current study is experimentally investigation of the two nonionic surfactants effects on altering wettability of reservoir rocks. Purpose of this work is to change the wettability to preferentially the water-wet condition. Also reducing the residual oil saturation (Sor) is the other purpose of this work. The wettability alteration of reservoir rock is measured by two main quantitative methods namely contact angle and the USBM methods. Results of this study showed that surfactant flooding is more effective in oil-wet rocks to change their wettability and consequently reducing Sor to a low value. Cedar (Zizyphus Spina Christi) is low priced, absolutely natural, and abundantly accessible in the Middle East and Central Asia. Based on the results, this material can be used as a chemical surfactant in field for enhancing oil recovery.

Date Syrup is a natural sweetener that is suitable replacement for sugar in food stuffs formulation. In this Research Amounts of 25-100 percent of sugar in Gaz formulation were replaced with date syrup and to study effect of its use in product formulation, characteristics of texture, color and sensory analyse of treatments were investigated. Statistical analyse of data was also done by SPSS software and Dankan test. The results of this research showed that amount of used date syrup in formulation had a significant effect on color parameters (L*,a*,b*), texture characteristics and sensory analyse of samples. By increase of date syrup in Gaz formulation, samples texture became softer than control sample and yellowness and redness index of samples were increased Doi: DOI: 10.12777/ijse.6.1.11-15 [How to cite this article: Shafiei, Z., Hojjatoleslami, M., Soha, S., and Shariati, M.A. 2014. The Influence of Malt Extraction Adding to UF Fresh Low Fat Cheese on Its Textural Properties. International Journal of Science and Engineering, 6(1):57-60. Doi: 10.12777/ijse.6.1.11-15

Introduction: The purpose of present research was to compare the effect of mental, physical and mental- physical exercises on the balance ability of blind students. Materials and Methods: Subjects of this semi-experimental research were 30 daughters with the maximum Visual acuity of 0.05 Diopter in the dominant eyes, who were selected through a simple non-probability sampling method. They were randomly divided into 3 equal groups of mental exercises (mean age 9.2 years); physical exercises (mean age 8.2 years) and combined exercises (mean age 9.6 years). Each group participated in an 8-week program consisted of 2 weekly sessions of 45 to 60 minutes each. The capability of static and dynamic balance was measured by Romberg and Balance beam tests respectively. Obtained data were statistically analyzed via independent t test, one way ANOVA and Post hoc Tukey test using SPSS software, version 18 (significance level was set at P ≤ 0.05). Results: Results showed that there was no significant difference between the above mentioned three practice methods considering static balance. Regarding to the dynamic balance, combined practice was the only method that resulted in a significantly improved performance. Moreover, between-group comparisons indicated significant advantage of combined method over either mental or physical practice alone. Conclusion: Based on the results of this study, it is concluded that a compensatory corrective mechanism is the possible cause of non significant differences between the static-balance performances of the three studied groups. Combined mental and physical practices may improve balance ability during execution of complicated movements. Keywords: Mental practices, Physical practices, Mental- physical practices, Balance capability, Blind students