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This paper aims to introduce a numerical investigation of aquatic locomotion using the smoothed particle hydrodynamics (SPH) method.

To model this problem, a simple improved SPH algorithm is presented that can handle complex geometries using updatable dummy particles. The computational code is validated by solving the flow over a two-dimensional cylinder and comparing its drag coefficient for two different Reynolds numbers with those in the literature.

Additionally, the drag coefficient and vortices created behind the aquatic swimmer are quantitatively and qualitatively compared with available credential data. Afterward, the flow over an aquatic swimmer is simulated for a wide range of Reynolds and Strouhal numbers, as well as for the amplitude envelope. Moreover, comprehensive discussions on drag coefficient and vorticity patterns behind the aquatic are made.

It is found that by increasing both Reynolds and Strouhal numbers separately, the anguilliform motion approaches the self-propulsion condition; however, the vortices show different pattern with these increments.

In the past decades, the desire to use natural source foods has increased because of environmental compatibility, safety and appropriate costs. Sonication is used in food industry owing to its short duration of process and saving energy. The purpose of this study is to investigate the effect of various maize starches in the batter on the oil absorption and quality assessment (moisture content) of chicken nuggets by using five mathematical models.

To determine the effects of different maize starches on oil absorption parameters, 5 per cent starches native, sonicated starch were substituted in batter instead of wheat flour. Suspensions contained native starch were treated with sonication (70 kHz, 5 min) using an ultrasound probe set. Samples were fried in a fryer at 150, 170 and 190°C for 1, 3and 5 min, respectively. Models were compared with R² and Arrhenius equation for estimating model prediction sufficiency.

Obtained results represented that between different formulated samples, maize starch with high temperature had main significant effect (p < 0.05) on moisture content of nuggets. During frying, the amount of oil loses significantly (p < 0.05) depended on temperature and time and sonication treatment.

Incorporation of sonication with maize starch at higher temperature on quality assessment has not been found.

A boiling surface with different initial roughness and under various nanoparticles volume fractions was studied in present work.

Develop a correlation and sensitivity analysis.

The results showed that for small (7.3 nm) and much larger (about 2,000 nm) surface roughness, compared to nanoparticle size of around 25 nm, the heat transfer rate of nanofluid diminishes relative to that of base fluid. The results also demonstrated that the boiling heat transfer rate is reduced by increasing the concentration of nanoparticles. For larger boiling surface roughness (480 nm) and nanoparticles volume fractions of less than 0.1 Vol.%, the value of heat transfer increases with the increase of nanoparticles concentration; and for those of more than 0.1 Vol.%, heat transfer rate decreases by adding more nanoparticles, significantly.

Finally, an equation was presented for estimating the wall superheat and the C_sf coefficient in terms of mentioned parameters.

This paper aims to study the fluid flow and heat transfer through a spiral double-pipe heat exchanger. Nowadays using spiral double-pipe heat exchangers has become popular in different industrial segments due to its complex and spiral structure, which causes an enhancement in heat transfer.

In these heat exchangers, by converting the fluid motion to the secondary motion, the heat transfer coefficient is greater than that of the straight double-pipe heat exchangers and cause increased heat transfer between fluids.

The present study, by using the Fluent software and nanofluid heat transfer simulation in a spiral double-tube heat exchanger, investigates the effects of operating parameters including fluid inlet velocity, volume fraction of nanoparticles, type of nanoparticles and fluid inlet temperature on heat transfer efficiency.

After presenting the results derived from the fluid numerical simulation and finding the optimal performance conditions using a genetic algorithm, it was found that water–Al₂O₃ and water–SiO₂ nanofluids are the best choices for the Reynolds numbers ranging from 10,551 to 17,220 and 17,220 to 31,910, respectively.

In Iran, the frequent occurrence of disasters has always been a major problem. In recent decades, disasters have created considerable challenges, especially in cities. Hence, understanding the levels of urban resilience (UR) and planning for addressing vulnerabilities plays a key role in the era of increasing risks and uncertainties. The present study aims to provide a comprehensive overview of the state of resilience of Iranian cities.

A systematic literature review method was used to determine how resilient Iranian cities are. To find relevant studies, the authors searched Iranian and international databases such as Scopus, ScienceDirect, SID and Magiran. There was no restriction on the inclusion date, meaning that all papers published up until September 16, 2021 were considered for inclusion. The PRISMA framework was used for literature search and selection and, finally, 153 studies focused on 52 cities of Iran were selected for the systematic review.

In general, the results showed that the level of resilience was low in Iranian cities. Also, informal settlements, worn-out urban fabrics and the central parts of cities showed lower resilience than other parts.

The results of the study can be used to inform municipal authorities, urban planners and non-governmental organizations of the actions that need to be taken to enhance the resilience of Iranian cities.

With respect to two new subjects, i.e. nanofluids and microchannels, in heat transfer systems and modern techniques used for building them, this paper aims to study on effect of using aluminum oxide nanoparticles in non-Newtonian fluid of aqueous solution of carboxy-methyl cellulose in microtube and through application of different slip coefficients to achieve various qualities on surface of microtube.

Simultaneously, the effect of presence of nanoparticles and phenomenon of slip and temperature jump has been explored in non-Newtonian nanofluid in this essay. The assumption of homogeneity of nanofluid and fixed temperature of wall in microtube has been used in modeling processes.

The results have been presented as diagrams of velocity, temperature and Nusselt Number and the investigations have indicated that addition of nanoparticles to the base fluid and increase in microtube slip coefficient might improve rate of heat transfer in microtube.

The flow of non-Newtonian nanofluid of aqueous solution of carboxy methyl cellulose-aluminum oxide has been determined in a microtube for the first time.

The present study aims to develop a risk-supported case-based reasoning (RS-CBR) approach for water-related projects by incorporating various uncertainties and risks in the revision step.

The cases were extracted by studying 68 water-related projects. This research employs earned value management (EVM) factors to consider time and cost features and economic, natural, technical, and project risks to account for uncertainties and supervised learning models to estimate cost overrun. Time-series algorithms were also used to predict construction cost indexes (CCI) and model improvements in future forecasts. Outliers were deleted by the pre-processing process. Next, datasets were split into testing and training sets, and algorithms were implemented. The accuracy of different models was measured with the mean absolute percentage error (MAPE) and the normalized root mean square error (NRSME) criteria.

The findings show an improvement in the accuracy of predictions using datasets that consider uncertainties, and ensemble algorithms such as Random Forest and AdaBoost had higher accuracy. Also, among the single algorithms, the support vector regressor (SVR) with the sigmoid kernel outperformed the others.

This research is the first attempt to develop a case-based reasoning model based on various risks and uncertainties. The developed model has provided an approving overlap with machine learning models to predict cost overruns. The model has been implemented in collected water-related projects and results have been reported.

In this way, the aim of this study is to expand and evelop the application of this technique in FMEA to rank failure modes of ESQ of academic libraries in an intuitionistic fuzzy environment. Assessment of electronic service quality (ESQ) of libraries is significantly important according to their major roles. It should be noted that the ESQ has a significant impact on customer satisfaction, which improves organizational performance. Accordingly, low ESQ means waste of organizational resources and poor user satisfaction. So, there is a dire need to reflect reasons inducing failure modes in academic library ESQ. Thus, investigation of failure modes affecting academic library ESQ is highly important. One solution in this area is utilization of the intuitionistic fuzzy (IF) failure mode and effects analysis (FMEA) as one of the widely used methods for prediction and identification of failure modes.

The present study in terms of objective is applied and in terms of the type of method is descriptive-analytical. The research sample included four experts of Yazd academic Libraries (Iran). To collect data, three types of questionnaires were distributed among experts. The purpose of the first questionnaire was to identify and reach an agreement on e-library failure modes. Type II questionnaire was used to determine the importance of identified risk factors and Type III questionnaire was used to prioritize the factors.

Results indicate that the difficulty of using websites, lack of provided information feedback to users and lack of links on the website to users' are the main priorities for improving ESQ in the studied academic libraries.

In this approach, the Intuitionistic fuzzy Elimination Et Choix Traduisant la REalité and technique for order of preference by similarity to ideal solution method were used to rank failure modes in academic library ESQ within the FMEA framework.]

Finding blue colorants from natural sources is extremely difficult and, usually, the anthocyanin compounds are used for producing the blue color. This study aims to apply the Red Cabbage as a natural colorant to obtain different colors on wool yarn, as well as specify the optimum dyeing condition by response surface methodology for obtaining a blue color.

The effect of dyeing process parameters such as mordant concentration, dyeing time, pH of dyeing bath and dyeing temperature examined in the color characteristics of the dyed wool samples.

The obtained results indicated that the diverse colors achieve by varying the dyeing process parameters, which is in the range of 26° up to 271°. The non-mordanted dyed wool samples showed a red and red brownish color (Hue angle = 26° up to 70°), and the mordanted dyed wool samples showed a blue and blue-greenish color (Hue angle = 230° up to 271°). The obtained blue color with the optimized dyeing condition presented a considerable good wash and lightfastness.

This study provides a promising application of Red Cabbage as a natural colorant for obtaining different colors by varying the dyeing process parameters such as pH and stannous ion concentrations. The stannous ions yielded a co-pigmentation and presented a blue color on wool fibers, which is extremely difficult to obtain with natural colorant.

The purpose of this study is to evaluate the impact of psychological entitlement and perceived organizational justice on cyberloafing.

In this study, a cross-sectional research design based on a questionnaire method was used to collect the required data from a sample of 226 employees working at selected universities in the city of Isfahan, Iran. To test the research hypotheses, structural equation modeling was used.

According to the findings, psychological entitlement could have a significant impact on perceived organizational justice and consequently perceived organizational justice could significantly influence cyberloafing. Moreover, psychological entitlement could significantly influence cyberloafing and finally, psychological entitlement could have a significant effect on cyberloafing through perceived organizational justice.

This research provides valuable insight for studying the relationship among psychological entitlement, perceived organizational justice and cyberloafing.