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With increasing aerodynamic and thermal loads, film cooling has been a popular technology integrated into the design of the modern gas turbine vane endwall, especially for the first-stage vane endwall. A staggering amount of research has been completed to quantify the effect of operating conditions and cooling hole geometrical properties. However, most of these investigations did not address the influence of the manufacturing tolerances, assembly errors, and operation degradations on the endwall misalignment. In this paper, uncertainty quantification (UQ) analysis was performed to quantify the impacts of upstream endwall misalignment uncertainties on the endwall film cooling performance and vane surface phantom cooling performance. The upstream endwall misalignment, step geometry with various step heights, commonly exists between the combustor exit and the first-stage vane endwall. Based on the non-intrusive polynomial chaos expansion (NIPC) and the uniform probability distribution assumption, the deviation (step height) uncertainties of the upstream endwall misalignment were quantified. To predict the endwall secondary flow and film cooling effectiveness in the transonic linear vane passage, the commercial computational fluid dynamic solver ANSYS FLUENT was used to numerically solve the three-dimensional steady-state Reynolds-Averaged Navier–Stokes (RANS) equations. The robustness analysis of endwall film cooling performance and phantom cooling performance to the upstream endwall misalignment was conducted for three design upstream step heights (ΔH): a baseline configuration (ΔH = 0 mm), two misaligned configurations with forward step (ΔH = −5 mm) and backward step (ΔH = 5 mm), respectively. Results show that the actual cooling performance has a high probability of deviating from the nominal value for the baseline configuration. The critical regions that are most sensitive to the upstream step misalignment are also identified by variances. The UQ results also show that the design geometry with a forward step has a more robust film cooling performance on endwall and phantom cooling performance on the vane pressure side surface, which means a smaller variance and a better expectation than the no-step configuration. In contrast, the design geometry with a backward step induces the reductions in the expectation of the film cooling effectiveness and coolant coverage and the amplification of performance fluctuations. This work provides a certain guiding direction for the optimization design for the upstream step geometry.

Purpose This study aims to using Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy and scanning electron microscope/energy dispersive Xray spectrometer to identify different automotive coatings for forensic purpose. Design/methodology/approach Two four-layered samples in a hit-and-run case were compared layer by layer with three different methods. FTIR spectroscopy was used to primarily identify the organic and inorganic compositions. Raman spectrum and scanning electron microscope/energy dispersive Xray spectrometer (SEM-EDS) were further used to complement the FTIR results. Findings Two weak and tiny peaks in one layer found between two samples by FTIR, Raman microscope and SEM-EDS verified the result of differences. The study used the three instruments in combination and found it’s effective in sensing coatings, especially in the inorganic additives. Research limitations/implications Using these three instruments in combination is more accurate than individually in multilayered coating analysis for forensic purpose. Practical implications The three different instruments all present unique information on the composition, and provided similar and mutually verifiable results on the two samples. Originality/value With this method, scientists could identify and discriminate important coating evidences with tiny but characteristic differences.

The underrepresentation of women in science, technology, engineering and math (STEM) fields is a key challenge in many countries. Extant studies have explored why women opt out of STEM fields and how to encourage women to enter these fields. The current research examined the use of dynamic information about the collective change in a behavior over time to increase women’s willingness and intention to embark on STEM fields. Across two experimental studies and a mini meta-analysis, we found that when exposed to a message about an increasing number of women choosing to pursue STEM careers over time, female students in high school (Study 1) and college (Study 2) were more likely to declare an intention to enter STEM fields and have more interest in STEM careers. Furthermore, we tested the mediating effects of self-efficacy and perceived identity compatibility (Study 2). The results showed that dynamic norms can increase women’s self-efficacy for pursuing a career in STEM fields and perceived identity compatibility, thereby leading to greater interest in STEM fields and more willingness to choose a STEM career.

Economic inequality is associated with a series of social outcomes, including health, social trust, and crime rates. However, little is known about the role of economic inequality as a characteristic of the socioecological environment in individuals' reproductive behavior. According to embodied capital theory, this research explored how individuals calibrate their reproductive timing to maximize payoffs to investment in embodied capital in an environment of high economic inequality. Five studies were conducted to test the hypothesis that higher economic inequality leads people to delay reproduction. Across nations (Study 1), we found that the average reproductive age is higher in nations with greater economic inequality. Study 2 found that people living in more economically unequal U.S. states tend to marry later. In Study 3, individuals who perceived higher levels of inequality in a given society planned to have their children later. Finally, in Study 4, the priming of high inequality led to a greater preference for delaying reproduction, which represented a desire to pursue one's development rather than to build a family (Study 4a and 4b). These results expand the literature regarding the effect of economic inequality on human behavior.

Vehicle purchase restriction policies greatly influence people’s behavior, especially their participation in the license plate lottery. This paper focuses on the socioeconomic characteristics and psychological factors of citizens participating in the license plate lottery, which can serve as a reference for policy makers aiming to guide rational participation in the lottery. A Multi-Index and Multi-Causal model were established based on social psychology, combined with the Theory of Planned Behavior (TPB). Perceived car necessity, perceived behavioral control, car ownership attitude and subjective norms were regarded as four latent psychological variables. Furthermore, the behaviors of license plate lottery participants in cities with purchase restriction policies were statistically analyzed from the perspectives of personal socioeconomic characteristics and psychological factors. The empirical research results reveal that the socioeconomic attributes of citizens have different degrees of influence on latent variables. Perceived car necessity is observed to have a significant direct impact on a citizen’s behavioral intention to participate in the lottery, which is also affected by perceived behavioral control. Car ownership attitude has the strongest impact on citizen behavior towards participating in the license plate lottery, followed by subjective norms, perceived behavioral control, and perceived car necessity. More specifically, the economic benefit associated with perceived behavioral control is identified as the critical factor in further promoting participation in the license plate lottery.

Virtual reality technology can provide immersive experiences to facilitate limb motor training, including visual, auditory, and force touching, etc. In this paper, we develop a VR-based hand motor rehabilitation system. This system collects and analyzes users’ limb behavior data, customizes and trains hand motor training programs according to different scenarios and different levels of difficulties, and integrates management, evaluation, customization, and feedback functions. Then we conduct several experiments to verify the effectiveness and usability of the rehabilitation system. Through the FMA, NHPT, and SUS scale assessments on healthy individuals, the analysis concluded that the average SUS score of all participants was 80, verifying that the hand rehabilitation system is practical and feasible. Upper limb motor disorder patients’ trials and data analysis will be carried out in the future.

Five studies (total valid N = 834) examined whether objectification (i.e., being treated as a tool or an object to achieve others' goals) reduces people's perceived authenticity and subjective well-being. Participants who experienced more objectification (Studies 1a and 1b), imagined being objectified (Study 2), or recalled a past objectification experience (Study 3) felt less authentic and reported lower levels of subjective well-being than their counterparts. Moreover, perceived authenticity mediated the link between objectification and subjective well-being (Studies 1a-3). In addition, offering objectified participants an opportunity to restore authenticity could enhance their well-being (Study 4). Taken together, our findings highlight the crucial role of authenticity in understanding when and why objectification decreases subjective well-being and how to ameliorate this relationship. Our findings also imply the effect of authenticity in understanding various psychological outcomes following objectification.

Previous studies have shown that economic inequality is associated with macrosocial outcomes and psychological processes. However, the role of economic inequality in social cognition is poorly understood. In this article, we propose that perceived economic inequality increases social vigilance. Three experiments were conducted to examine this idea by manipulating the perception of economic inequality. The results revealed that participants in high-inequality environments exhibited higher levels of social vigilance than in low-inequality environments. Furthermore, perceived competition could mediate the link between economic inequality and social vigilance (Experiments 2–3). The findings expand the literature regarding the effect of economic inequality on social cognition and help people better understand the consequences of economic inequality.

Shared autonomous vehicle systems are anticipated to offer cleaner, safer, and cheaper mobility services when autonomous vehicles are finally implemented on the roads. The evaluation of people&rsquo, s intentions regarding shared autonomous vehicle services appears to be critical prior to the promotion of this emerging mobility on demand approach. Based on a stated preference survey in Nagoya, Japan, the preference for shared autonomous vehicle services as well as willingness to pay for these services were examined among 1036 respondents in order to understand the relationship between people&rsquo, s socioeconomic characteristics and their preferred shared autonomous vehicle services. For this purpose, k-modes clustering technique was selected and six clusters were obtained. Six groups with respect to different interests on shared autonomous vehicle services were clustered. The result of correlation analysis and discussion of willingness to pay on services provided insightful results for the future shared autonomous vehicle services. This study not only aids in revealing the demands of customer different clusters, but also states the prospective needs of users for stakeholders from research, policymaker and industry field, who are preparing to work on promoting shared autonomous vehicle systems, and subsequently, develops an optimum transportation mode by considering both demand and services as a whole.

With the addition of poly (butylene-adipate-terephthalate) (PBAT) and a commercial grade epoxy-functionalized oligomer Joncryl ADR@-4368 (ADR), a blend of polylactic acid (PLA) and sisal fibers (SF) were melt-prepared via in-situ reactive process to improve the toughness and interfacial bonding of polylactide/sisal fiber composites. Fourier Transform infrared spectroscopy (FTIR) analysis demonstrated chemical bonding between sisal fibers and matrix, and scanning electron microscope characterization indicated the enhancement of interfacial adhesion between PLA matrix and sisal fibers. The micro-debonding test proved that the interfacial adhesion between PLA and SF was improved because of ADR. The presence of ADR behaved like a hinge among sisal fibers and matrix via an in-situ interfacial reaction, and compatibility between PLA and PBAT was also augmented. The introduction of PBAT exerted a plasticization effect on composites. Therefore, the toughness of PLA/SF composites was significantly elevated, while the tensile strength of composites could be well preserved. The paper focused on the demonstration of interfacial interaction and structure&ndash, properties relationship of the composites.

The influence rule of the content ratio of cellulose, hemicellulose, and lignin on the tensile strength of sisal fibers (SFs) and the interfacial strength of SFs and poly lactic acid (PLA) ...

The Industrial Internet of Things is cited as the latest means for making manufacturing more flexible, cost effective, and responsive to changes in customer demands. In this paper, we present a mobile cloud based scheduling strategy for the industrial Internet of Things. Several computing paradigms, such as mobile cloud computing, fog computing, and edge computing can be integrated to the industrial Internet of Things, which allow to offload tasks to the cloud for execution. We model the task scheduling problem as an energy consumption optimization problem, while taking into account task dependency, data transmission, and some constraint conditions, such as response time deadline and cost, and further solve it by genetic algorithms. A series of simulation experiments are conducted to evaluate the performance of the algorithm and the results have shown that our proposal is more efficient than the baseline approach.

Device-to-device (D2D) communications enable direct communications among mobile entities, which brings new revolutions to existing cellular networks. Many use cases which can benefit from D2D are introduced such as vehicles-to-vehicles communication, vehicles-to-infrastructure communication, machine-to-machine communication, and so on. With the help of these information communication techniques, we propose a real-time traffic signal control approach to relieve traffic problems in this paper. Currently, a series of traffic problems, such as traffic congestion, traffic accidents, and vehicle exhaust emission, are increasingly inconveniencing city residents, especially in rush hours. One of the most dominating approaches to relieve the traffic congest is to determine the phase timing of traffic signals. However, a major shortcoming of the existing phase timing related control strategies is of highly computational complexity, which causes, to some extent, a response delay. The approach based on D2D communication, in this paper, on one hand can collect data of various types via sensors and actuators and on the other hand can reduce the response time as much as possible. Specifically, considering an intersection with four legs, we encoded the corresponding set of signal lights of each leg using a genetic algorithm. To evaluate the efficiency of phase timing plan in this paper, we have conducted extensive simulations, and the results show that our approach can respond to the considered traffic flow within one second. Compared with other traffic signal control systems, the performance is improved almost by 67% with regards to the queue length waiting at the intersections during traffic signal light cycle(s).

Vehicle purchase restriction policies greatly influence people’s behavior, especially their participation in the license plate lottery. This paper focuses on the socioeconomic characteristics and psychological factors of citizens participating in the license plate lottery, which can serve as a reference for policy makers aiming to guide rational participation in the lottery. A Multi-Index and Multi-Causal model were established based on social psychology, combined with the Theory of Planned Behavior (TPB). Perceived car necessity, perceived behavioral control, car ownership attitude and subjective norms were regarded as four latent psychological variables. Furthermore, the behaviors of license plate lottery participants in cities with purchase restriction policies were statistically analyzed from the perspectives of personal socioeconomic characteristics and psychological factors. The empirical research results reveal that the socioeconomic attributes of citizens have different degrees of influence on latent variables. Perceived car necessity is observed to have a significant direct impact on a citizen’s behavioral intention to participate in the lottery, which is also affected by perceived behavioral control. Car ownership attitude has the strongest impact on citizen behavior towards participating in the license plate lottery, followed by subjective norms, perceived behavioral control, and perceived car necessity. More specifically, the economic benefit associated with perceived behavioral control is identified as the critical factor in further promoting participation in the license plate lottery.

Untreated sisal and coir fibers (USF and UCF), alkali-treated sisal and coir fibers (ASF and ACF), and alkali-treated sisal/coir hybrid fibers (ASF/ACF) reinforced polylactide (PLA) composites were prepared by compression molding technique. The materials were characterized in terms of tensile, flexural, and impact properties. While all mechanical tests showed that the composites reinforced by alkali-treated fibers could withstand more fracture strain than untreated fibers reinforced composites which could be attributed to the improved interfacial adhesion between alkali-treated fibers and matrix related to the remove of lignin, hemicellulose and pectin by the alkali treatment, the addition of ACF in PLA/ASF composites improved the impact strength of PLA/ASF/ACF composites and showed a positive effect. More fibers tended to be torn apart or fractured, but less pulled out with the increase of coir fiber content. Compared to other composites, the ASF/ACF-reinforced PLA composites offered superior mechanical properties when the ratio of sisal to coir was 7:3. POLYM. COMPOS., 2017. © 2017 Society of Plastics Engineers

The in situ reactive interfacial compatibilization and properties of polylactide/sisal fiber biocomposites made via melt blending with an epoxy-functionalized terpolymer elastomer, ethylene/methyl acrylate/glycidyl methacrylate (EGMA), were investigated. Scanning electron microscopy results showed that the introduction of EGMA improved the interfacial adhesion between the sisal fibers (SF) and matrix, which was ascribed to the improved interfacial compatibilization between the polylactide and fibers via in situ reaction with EGMA during the melt-blending processing. It was also observed that the EGMA tends to weld on the surface of the fibers, which is called a self-weld fiber structure. The interfacial reaction and microstructure of the composites were further investigated by FTIR characterization, and thermal and rheological analyses. The results demonstrated that the mobility of the polylactide molecular chain was restricted due to the enhanced interfacial interaction of the composites. The addition of EGMA improved the toughness of the polylactide/sisal fiber composites without much decline in the tensile strength. Polylactide/sisal fiber composites with a good stiffness-toughness balance were obtained.

A simple approach to decorate multi-walled carbon nanotube (MWCNT)&ndash, reduced graphene oxide (RGO) hybrid nanoparticles with zinc oxide (ZnO) nanorods is developed to improve the electrical and mechanical properties of poly(vinyl chloride) (PVC)/MWCNT&ndash, RGO composites. The ZnO nanorods act as &ldquo, joint&rdquo, in three-dimensional (3D) MWCNT&ndash, RGO networks and the hybrid particles strongly interact with PVC chains via p-&pi, stacking, hydrogen bonds, and electrostatic interactions, which we confirmed by scanning electron microscopy (SEM) and Raman analysis. By introducing the ZnO nanorods, the RGO&ndash, ZnO&ndash, MWCNT hybrid particles increased 160% in capacitance compared with MWCNT&ndash, RGO hybrids. Moreover, the addition of RGO&ndash, MWCNT to PVC resulted in the mechanical properties of PVC being enhanced by 30.8% for tensile strength and 60.9% for Young&rsquo, s modulus at the loadings of 2.0 weight percent (wt.%) and 1.0 wt.%, respectively. Meanwhile, the electrical conductivity of PVC increased by 11 orders of magnitude, from 1 &times, 10&minus, 15 S/m to 1 &times, 4 S/m for MWCNT&ndash, RGO loading at 5.0 wt.%.

To improve the interfacial bonding of sisal fiber reinforced polylactide biocomposites, polylactide (PLA) and sisal fibers (SF) were melt-blended to fabricate bio-based composites via in situ reactive interfacial compatibilization with the addition of an epoxy-functionalized oligomer (ADR). The FTIR analysis and SEM characterization demonstrated that PLA molecular chain was bonded to the fiber surface and epoxy-functionalized oligomer played a hinge-like role between sisal fibers and PLA matrix, which resulted in improved interfacial adhesion between fibers and PLA matrix. The interfacial reaction and microstructures of composites were further investigated by thermal and rheological analyses, which indicated that the mobility of the PLA molecular chain in composites was restricted because of the introduction of ADR oligomer, which in turn reflected the improved interfacial interaction between SF and PLA matrix. These conclusions were further investigated by the calculated activation energies of glass transition relaxation (△Ea) of composites via dynamic mechanical analysis. The mechanical properties of PLA/SF composites were simultaneously reinforced and toughened via addition of ADR oligomer. The interfacial interaction and structure-properties relationship of composites are key points of this study.

Due to some inherent defects of mobile devices, such as limited battery energy, insufficient storage space, mobile applications are confronted with many challenges in mobility management, quality of service (QoS) insurance, energy management and security issues, which has stimulated the emergence of many computing paradigms, such as Mobile Cloud Computing (MCC), Fog Computing, etc. These computation paradigms allow to offload some tasks to the cloud for execution, which makes task scheduling crucial both at the mobile device and in the mobile cloud. In this paper, we models this problem as an energy consumption optimization problem, while taking into account task dependency, data transmission and some constraint conditions such as response time deadline and cost, and further solve it by genetic algorithms. A series of simulation experiments are conducted to evaluate the performance of the algorithm and the results have shown that our proposal is more efficient than the baseline approach.

The acetate-based ionic liquid (AcIL) [EMIM][Ac] does not fully dissociated into isolated ions in extremely diluted water solution (0.5 mol% of IL). Still, ion pairs exist via the through-space weak van der Waals force between H6 of the cation and Hb of the anion. In this ion pairs, except for H6 and Hb, all other hydrogen atoms (i.e., H2, H4, H5, H7, H8) are totally hydrated by water; the acetate anion suffers from a more extent of hydration due to its higher hydrophilicity. One dimension (1D) nuclear magnetic resonance (NMR) ( 1 H, 13 C, 15 N,) and two dimensions (2D) NMR are used in this study. 2D NMR used includes through-space 1 H– 1 H NOSEY (nuclear Overhauser effect spectroscopy), through-bond 1 H– 13 C HSQC COSY (heteronuclear single-quantum correlation spectroscopy), and HMBC COSY (heteronuclear multiple-bond correlation spectroscopy). The much stronger (H245/anion) or weaker (H78/anion) hydrogen-bonding interaction in the pure [EMIM][Ac] disfavors the association of ions in the diluted state due to a better hydrogen-bonding donor or a weaker hydrogen-bonding strength, respectively. However, H6/anion with the moderate hydrogen-bonding strength and the moderate hydrogen-bonding donating ability existed in the pure [EMIM][Ac] plays the role in determining the associating ion pairs. The proportion of hydrogen-bonding interaction between hydrogens in the cation with anion (100%) is approximately quantified in descending order as follows: H2 (42%), H4 (24%), H5 (22%), H6 (6%), H7 (5%), and H8 (1%).

As suburbanization and unprecedented population aging are converging, enhanced personal mobility for suburban residents is required. In this study, a collaborative scheme involving park-and-ride services associated with public transport and a shared autonomous vehicle system are proposed. Two residential areas in the Nagoya metropolitan region, Japan, are considered: a residential area at the outer edge of a subway line and a commuter town with a nearby railway station. Three user groups are assumed: park-and-ride commuters who park shared autonomous vehicles at the station and take the train to their workplaces, inbound commuters who disembark from trains at the station and use the vehicles to reach their workplaces within the target area, and elderly and disabled residents, who use shared autonomous vehicles for trips within the target area. The system performance is investigated through agent-based simulation. The results suggest that, in the edge case, approximately 400 shared autonomous vehicles can facilitate more than 10,000 trips at an appropriate level of service. For the commuter town, fewer than 400 vehicles can provide rapid responses with a wait time of approximately 5 min for more than 5000 trips per day. Thus, the proposed system can feasibly provide a quick response service.

To improve the interfacial bonding of sisal fiber-reinforced polylactide biocomposites, polylactide (PLA) and sisal fibers (SF) were melt-blended to fabricate bio-based composites via in situ reactive interfacial compatibilization with addition of a commercial grade epoxy-functionalized oligomer Joncryl ADR@-4368 (ADR). The FTIR (Fourier Transform infrared spectroscopy) analysis and SEM (scanning electron microscope) characterization demonstrated that the PLA molecular chain was bonded to the fiber surface and the epoxy-functionalized oligomer played a hinge-like role between the sisal fibers and the PLA matrix, which resulted in improved interfacial adhesion between the fibers and the PLA matrix. The interfacial reaction and microstructures of composites were further investigated by thermal and rheological analyses, which indicated that the mobility of the PLA molecular chain in composites was restricted because of the introduction of the ADR oligomer, which in turn reflected the improved interfacial interaction between SF and the PLA matrix. These results were further justified with the calculation of activation energies of glass transition relaxation (∆Ea) by dynamic mechanical analysis. The mechanical properties of PLA/SF composites were simultaneously reinforced and toughened with the addition of ADR oligomer. The interfacial interaction and structure–properties relationship of the composites are the key points of this study.

In this study, regenerated cellulose was prepared from ionic liquid 1-butyl-3-methylimidazolium acetate ([Bmim]Ac) solution using anti-solvent compressed CO 2 of different pressures. And other anti-solvents like water, ethanol and acetonitrile were also employed to regenerate cellulose to provide comparisons. The two-dimensional nuclear magnetic resonance (2D NMR), namely heteronuclear single quantum coherence (HSQC) and heteronuclear multiple bond coherence (HMBC), and attenuated total reflectance Fourier transform infrared spectroscopy (ATR–FTIR) indicated that carboxylate zwitterions [Bmim + -COO − ] formed through the chemical reactions between CO 2 and [Bmim]Ac. Besides, FTIR, wide-angle X-ray diffraction (XRD), thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to provided structure characterization of native and regenerated cellulose using different anti-solvents. The results show that the crystallinity of cellulose decreases during the dissolution and regeneration process. And a crystal transformation of cellulose I to cellulose II was verified. The stability of the regenerated cellulose is lower than that of native cellulose. A higher compressed CO 2 pressure results in a smoother surface, a thicker shape and a more homogeneous texture of regenerated cellulose.

In a monotonous travelling environment, the single-vehicle run-off-roadside accidents occur easily. The injuries and fatalities caused by those accidents are significant components of the annual road casualties. The causation is the complex interaction of the visual effects on the roadside objects’ conspicuity. So the conspicuity enhancement needs to be considered in the roadside objects design to provide a temporary restoration of alertness and vigilance to drivers. Factors contributing to the conspicuity of the roadside objects were analyzed in this paper. A driving simulator study was conducted in order to extrapolate the relationship between the legibility distances and the objects and to quantify the conspicuity of the roadside objects different in basic features. The conclusions of this paper were firstly, a significant correlation existed between the mean legibility distance and the object’s size. The mean legibility distance was in a significant exponential proportion to the object’s size. Secondly, the triangle’s legibility was better than that of the rectangle and round contours. Only when the roadside object was combined with the suitable contour and size did the best visual quality come. To some extent, the conclusions could provide theoretical tools and strategies to optimize the dimensional design of the roadside objects in order to maintain the roadside safety.