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In this paper, the relationship of brand logo and purchase intention is investigated along with the mediating role of customer satisfaction, brand preference and brand attitude. The research is conducted on an online passenger transport company called Tapsi.

In this study, we examine the positive effect of brand logo on brand attitude, consumer satisfaction and strengthening the intention to buy and brand preference by customer satisfaction. The statistical population was randomly selected. We design a conceptual model and then prepare a standard online questionnaire and send it to the target groups. Among this, the participants, 59% are women and 41% are men. After collecting the data through the software Smart-PLS3, we start the analysis. According to Cronbach's alpha and AVE, the validity and reliability of the model are confirmed.

The study shows that the brand logo has a positive and direct influence on customer attitude and satisfaction, and customer satisfaction mediates the purchase intention and brand preference. Given that the brand logo describes the company, managers must be very sensitive to design of a proper logo and spend enough time and money on it.

Few studies have examined the effectiveness of the brand logo the present study and the results show that the brand logo and its structures are directly related to brand attitude as a result of consumer satisfaction in all services even transportation services. The first thing consumers see when they first use a company’s services is the company logo. The brand and its logo can change the attitude and decision of the customer. Past studies have also shown that the brand logo can have a direct impact on customer satisfaction and customer preference for the brand. Therefore a model was prepared and the mentioned variables were selected. Brand preference as a mediating variable has a positive role on buying intention. However all relationships and their predictive power have been confirmed.

In online shopping, there is often a risk due to the inability to check the products. As a result, it can reduce the impact of factors affecting the intention to buy online, which is a significant point in e-commerce. The purpose of this research is to investigate the impact of the evidence and the perceived usefulness of a store site on the existing risk and online participation of customers for online shopping.

The statistical population of this research is people who have had the experience of online shopping at the Digikala store. The research method was descriptive-survey and the samples were randomly selected. A questionnaire was also used to collect information. Structural and statistical analysis of the model was done by SmartPLS3 software.

In this research, the authors found that the perceived usefulness (benefits of the site) has a favorable effect on the online participation of customers. It can also reduce the risk of online shopping. This research suggests good ways to increase sales to those who have a store site. The present research provides useful findings for those who sell their products online.

This research specifically examines the interaction of customers with sellers and can be a help for progress in e-commerce. In this study, perceived risk and participation as mediating variables, information and perceived usefulness on the site as independent variables and online shopping intention a dependent variables. This research was done about Digikala's online store. The results were obtained with the participation of customers in completing the questionnaire. Then the theoretical model and the background of the research are examined and then the hypotheses are evaluated according to the statistical results and finally, the research results and limitations are stated.

The purpose of this study is to explore the association between intake of different types of dietary fats with breast cancer (BC) risk in Iranian women.

A total of 540 women (180 women with BC and 360 healthy women) were recruited from Shohadaye Tajrish hospital, Tehran, Iran. Data on anthropometric measurements, physical activity, smoking and alcohol consumption were collected. The food frequency questionnaire was used to assess the intake of fatty acids including saturated fatty acids, mono unsaturated fatty acids, poly unsaturated fatty acids, macronutrients, total fat, cholesterol, and calorie.

The cases had significantly higher BMI (29.19 ± 3.2 vs 27.27 kg/m2 ± 2.8) and higher intake of calorie (2737 ± 925 vs 2315 ± 1066 kcal/d, P = 0.01), carbohydrate (402 ± 125 vs 312 ± 170 kcal/d, P = 0.01) and ω−6 fatty acids (5.45 ± 6.9 vs 3.39 ± 0.59 g/d, P = 0.001) compared to the control group . Higher consumption of ω−6 fatty acids was related with higher risk of BC (OR = 5.429, CI95%:2.5–11.79, P = 0.001) The association between BC and intake of omega-6 fatty acids remained significant after adjustments for age, BMI, for using alcohol drinks, smoking, physical activity, calorie intake, protein intake and carbohydrate intake.

There are insufficient studies to investigate the association of different types of fatty acids with BC. This study found that higher omega-6 fatty acids intake was associated with increased risk of BC in women.

The production of long-lasting fragrant semi-worsted fabrics using dendritic compounds as one of the nano size materials is concerned. Also quantitative assessments of the odour intensity of the fragrant fabrics using an electronic-nose (E-nose) are made. The paper aims to discuss these issues.

The semi-worsted fabrics were perfumed using the second generation of polypropylene-imine (PPI) dendrimer as a host molecules. The ginseng and rosewater fragrances as guest molecules were applied into the PPI dendrimer to produce long-lasting fragrant fabrics. The odour intensity as well as long-lasting properties of the fragrant fabrics perfumed recently and the other sample perfumed one year ago were evaluated via E-nose fabricated in our laboratory. Physical properties of the fragrant fabrics were compared to the non-fragrant ones.

The interaction between ginseng and rosewater fragrances with the second generation of PPI dendrimer into the semi-worsted fabrics made a long-lasting fragrant fabrics without considerable impacts on bending length, air permeability and wrinkle recovery angles based on statistical analysis. However, the effects of making fragrant fabrics on the increasing weight are significant. In addition, the E-nose was successfully used to monitor the release of ginseng and rosewater fragrance from the fabrics by the response patterns of a temperature-modulated chemo-resistive gas sensor. E-nose analysis showed that the aroma intensity released from the old fragrant semi-worsted fabrics has no obvious diversity from that of new fragrant fabrics.

The findings suggest that the semi-worsted fabrics perfumed with dendritic materials revealed excellent sustained release property.

The purpose of this paper is to analyze the effects of supply chain coordination on inventory management while the retailer inventory cycle consists of a shortage period and the backorder rate linearly decreases as a function of shortage duration. It is intended to consider how on‐hand inventory and shortage durations are altered when the decisions are centralized.

Mathematical modelling of inventory costs for the retailer and the vendor is used to formulate objective functions. The vendor sets his inventory period as an integer multiple (n) of the retailer inventory cycle in which the integer multiple is a decision variable. Solution spaces of models are analyzed to determine two other decision variables including, on‐hand inventory duration and shortage length.

The integrated model consists of a unique pseudo convex area when (n) is fixed and as a result, there is a unique minimum point. Based on numerical examples and sensitivity analysis, in most situations coordinated inventory management reduces total costs of the supply chain and cost reduction rate increase at larger production rates.

This paper is a combination between production‐inventory models in two‐stage supply chains and partial backordering, which has appeared in single inventory models. To the best of the authors' knowledge, no mathematical model has yet been proposed. Moreover, the benefits of synchronization are analyzed through numerical examples.

The purpose of this study is two phase modeling of Water/Cu nanofluid forced convection in different arrangements of elliptical tube banks in a two-dimensional space.

The arrangements of tube banks have been regarded as equal spacing triangle (ES), equilateral triangle (ET) and the rotated square (RS). The obtained results indicate that, among the investigated arrangements, the RS arrangement has the maximum value of heat transfer with cooling fluid. Also, the changes of Nusselt number and the local friction factor are under the influence of three main factors including volume fraction of slid nanoparticles, the changes of fluid velocity parameters on the curved surface of tube and flow separation after crossing from a specified angle of fluid rotation.

In Reynolds number of 250 and in all arrangements of the tube banks, the behavior of Nusselt number is almost the same and the separation of flow happens in almost 155-165 degrees from fluid rotation on surface. In RS arrangement, due to the strength of vortexes after fluid separation, better mixture is created and because of this reason, after the separation zone, the level of local Nusselt number graph enhances significantly.

In this research, the laminar and two-phase flow of Water/Cu nanofluid in tube banks with elliptical cross section has been numerically investigated in a two-dimensional space with different longitudinal arrangements. In this study, the effects of using nanofluid, different arrangements of tube banks and the elliptical cross section on heat transfer and cooling fluid flow among the tube banks of heat exchanger have been numerically simulated by using finite volume method.

Increasing heat transfer rate in spiral heat exchangers is possible by using conventional methods such as increasing number of fluid passes and counter flowing. In addition, newer ideas such as using pillows as baffles in the path of cold and hot fluids and using nanofluids can increase heat transfer rate. The purpose of this study is to simulate turbulent flow and heat transfer of two-phase water-silver nanofluid with 0-6 Vol.% nanoparticle concentration in a 180° path of spiral heat exchanger with elliptic pillows.

In this simulation, the finite volume method and two-phase mixture model are used. The walls are subjected to constant heat flux of q″ = 150,000 Wm⁻². The inlet fluid enters curves path of spiral heat exchanger with uniform temperature T_in = 300 K. After flowing past the pillows and traversing the curved route, the working fluid exchanges heat with hot walls and then exits from the section. In this study, the effect of radiation is disregarded because of low temperature range. Also, temperature jump and velocity slipping are disregarded. The effects of thermophoresis and turbulent diffusion on nanofluid heat transfer are disregarded. By using finite volume method and two-phase mixture model, simulations are performed.

The results show that the flow and heat transfer characteristics are dependent on the height of pillows, nanoparticle concentration and Reynolds number. Increasing Reynolds number, nanoparticle concentration and pillow height causes an increase in Nusselt number, pressure drop and pumping power.

Turbulent flow and heat transfer of two-phase water-silver nanofluid of 0-6 per cent volume fraction in a 180° path of spiral heat exchanger with elliptic pillows is simulated.

Water/Al₂O₃ nanofluid with volume fractions of 0, 0.3 and 0.06 was investigated inside a rectangular microchannel. Jet injection of nanofluid was used to enhance the heat transfer under a homogeneous magnetic field with the strengths of Ha = 0, 20 and 40. Both slip velocity and no-slip boundary conditions were used.

The laminar flow was studied using Reynolds numbers of 1, 10 and 50. The results showed that in creep motion state, the constricted cross section caused by fluid jet is not observable and the rise of axial velocity level is only because of the presence of additional size of the microchannel. By increasing the strength of the magnetic field and because of the rise of the Lorentz force, the motion of fluid layers on each other becomes limited.

Because of the limitation of sudden changes of fluid in jet injection areas, the magnetic force compresses the fluid to the bottom wall, and this behavior limits the vertical velocity gradients. In the absence of a magnetic field and under the influence of the velocity boundary layer, the fluid motion has more variations. In creeping velocities of fluid, the presence or absence of the magnetic field does not have an essential effect on Nusselt number enhancement.

In lower velocities of fluid, the effect of the jet is not significant, and the thermal boundary layer affects the entire temperature field. In this case, for Hartmann numbers of 40 and 0, changing the Nusselt number on the heated wall is similar.

In the present study, laminar steady flow of nanofluid through a trapezoidal channel is studied by using of finite volume method. The main aim of this paper is to study the effect of changes in geometric parameters, including internal and external dimensions on the behavior of heat transfer and fluid flow. For each parameter, an optimum ratio will be presented.

The results showed that in a channel cell, changing any geometric parameter may affect the temperature and flow field, even though the volume of the channel is kept constant. For a relatively small hydraulic diameter, microchannels with different angles have a similar dimensionless heat flux, while channels with bigger dimensions show various values of dimensionless heat flux. By increasing the angles of trapezoidal microchannels, dimensionless heat flux per unit of volume increases. As a result, the maximum and minimum heat transfer rate occurs in a trapezoidal microchannel with 75° and 30 internal’s, respectively. In the study of dimensionless heat flux rate with hydraulic diameter variations, an optimum hydraulic diameter (Dh) was observed in which the heat transfer rate per unit volume attains maximum value.

This optimum state is predicted to happen at a side angle of 75° and hydraulic diameter of 290 µm. In addition, in trapezoidal microchannel with higher aspect ratio, dimensionless heat flux rate is lower. Changing side angles of the channels and pressure drop have the same effect on pressure drop. For a constant pressure drop, if changing the side angles causes an increase in the rectangular area of the channel cross-section and the effect of the sides are not felt by the fluid, then the dimensionless heat flux will increase. By increasing the internal aspect ratio (t_2/t_3), the amount of t_3 decreases, and consequently, the conduction resistance of the hot surface decreases.

The effects of geometry of the microchannel, including internal and external dimensions on the behavior of heat transfer and fluid flow for pressure ranges between 2 and 8 kPa.

The crucial importance of innovation leadership for high technology small and medium-size enterprises (SMEs) has been suggested in the literature. However, few studies empirically examined the impact of leadership style on innovation work behavior (IWB) of employees in the context of SMEs. Furthermore, our knowledge is limited about how leaders of high technology SMEs influence the IWB of their employees. The present study explores the effect of entrepreneurial leadership on IWB of employees and introduces creative self-efficacy and support for innovation as the mechanisms through which the leaders encourage their employees' IWB in information and communications technology (ICT) SMEs in Iran.

The sample was selected from high technology ICT SMEs using the simple random sampling method and included 175 CEOs and owner-managers of the businesses. We used validated questionnaires to test the hypothesized relationships between entrepreneurial leadership, IWB, creative self-efficacy and support for innovation.

The findings show that entrepreneurial leadership has a significant and positive impact on IWB of employees in ICT SMEs. Furthermore, employees’ creative self-efficacy and leaders’ support for innovation mediate the relationship between entrepreneurial leadership and IWB. Implications of the results and suggestions for developing IWB among the employees of high technology SMEs are suggested.

The study makes important contributions to both entrepreneurial leadership and the innovation behavior literature and theory development specifically in high technology SMEs in the transitioning economy of Iran. The findings also contribute to the existing empirical studies on how entrepreneurial leadership affects IWB of employees by examining the mediating role of creative self-efficacy and support for innovation and in the settings of ICT high technology SMEs.