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The purpose of this study is investigate the transient aerodynamic characteristics of high-speed vehicle with body roll motion under crosswind condition to improve aerodynamic stability.

An overset mesh was used to simulate the rolling motion of the vehicle body. A wind tunnel experiment was conducted to validate the numerical method.

The results revealed that the vehicle’s aerodynamic characteristics changed periodically with the body’s periodic motion. In the absence of crosswind, the pressure distribution on the left and right sides of the vehicle body was symmetrical, and the speed streamline flowed to the rear of the vehicle in an orderly manner. The maximum aerodynamic lift observed in the transient simulation was −0.089, which is approximately 0.70 times that of the quasi-static simulation experiment. In addition, the maximum aerodynamic side force observed in the transient simulation was 0.654, which is approximately 1.25 times that of the quasi-static simulation experiment.

The aerodynamic load varies periodically with the vehicle body’s cyclic motion. However, the extreme values of the aerodynamic load do not occur when the vehicle body is at its highest or lowest position. This phenomenon is primarily attributed to the mutual interference of airflow viscosity and the hysteresis effect in the flow field, leading to the formation of a substantial vortex near the wheel. Consequently, the aerodynamic coefficient at each horizontal position becomes inconsistent during the periodic rolling of the vehicle body.

The purpose of this paper is to make explicit how marketers employed in the pharmaceutical sector can ensure that the company is positioned in the industry as a result of a sustainable competitive advantage being achieved. Various factors are highlighted, including high research and development costs, stringent government regulations and cultural factors such as religion.

The new product launch strategy model outlined in this paper was developed from both secondary and primary sources. A literature review was undertaken, a number of in‐depth personal interviews and a focus group session were conducted, which involved managers within a pharmaceutical company. The research strategy encompassed the case study method and the NPLS model was validated and can be viewed as generalisable.

It is clear from the research undertaken that some marketing models are viewed as being too complex; however, it is generally appreciated that marketing models can be used to interpret complex relationships that are evident in a marketing system.

Two weaknesses associated with the model were identified. First, the assumption that there was a one‐way relationship between the strategic launch decisions and the tactical launch decisions and, second, a feedback mechanism was absent that would provide users of the model with a means for evaluating their decisions and identifying alternative strategies and tactics. The model was amended and a feedback mechanism was introduced.

The NPLS model can be used by marketing practitioners to enhance communication between corporate level staff and subsidiary level staff, and can be used to implement and/or facilitate the strategic marketing concept within a pharmaceutical company. The model can also be used to focus attention on risk reduction/elimination associated with market entry.

The NPLS model is an addition to marketing knowledge and can assist marketing academics and researchers to understand better how marketing models can be constructed and implemented. The model can also be used by marketing practitioners employed by pharmaceutical companies to make tactical and strategic decisions; to evaluate a new product launch strategy; and to devise international marketing entry plans and strategies.

The purpose of this paper is to provide an investigation on a new kind of photocatalytic material, namely, the porous ceramic foam loading titanium dioxide, which can make an effective photocatalytic degradation of the methyl orange (MO) solution in the wastewater.

The natural zeolite powder has been used as the primary raw material to produce a sort of lightweight porous ceramic foam by impregnating polymer foam in slurry and then sintering. With the sol-gel method, a kind of open-cell reticular porous ceramic foam loading TiO₂ film was obtained having a good photocatalytic action, and the resultant porous composite product presents the bulk density of 0.3~0.6 g/cm³ to be able to float on water.

The MO could tend to be completely degraded in the solution with a certain concentration by the TiO₂-loaded ceramic foam irradiated with ultraviolet light, and this composite foam was found to have high degradation efficiency for the MO solution in a wide range of pH.

This work presents a TiO₂-loaded ceramic foam that can effectively photo-catalyze to degrade the MO in water, and the degradation efficiency were examined under different conditions of the MO solution with various pH values.

Many applications in intelligent transportation demand accurate categorization of vehicles. The purpose of this paper is to propose a working image-based vehicle classification system. The first component vehicle detection is implemented by applying Dalal and Triggs's histograms of oriented gradients features and linear support vector machine (SVM) classifier. The second component vehicle classification, which is the emphasis of this paper, is accomplished by an improved stacked generalization. As an effective ensemble learning strategy, stacked generalization has been proposed to combine multiple models using the concept of a meta-learner. However, it was found that the well-known meta-learning scheme multi-response linear regression (MLR) for stacked generalization performs poorly on the vehicle classification.

A new meta-learner is then proposed based on kernel principal component regression (KPCR). The stacked generalization scheme consists of a heterogeneous classifier ensemble with seven base classifiers, i.e. linear discriminant classifier, fuzzy k-nearest neighbor, logistic regression, Parzen classifier, Gaussian mixture model, multiple layer perceptron and SVM.

Experimental results using more than 2,500 images from four types of vehicles (bus, light truck, car and van) demonstrated the effectiveness of the proposed approach. The improved stacked generalization produced consistently better results when compared to any of the single base classifier used and four other beta learning algorithms, including MLR, majority voting, logistic regression and decision template.

With the seven base classifiers, the KPCR-based stacking offers a performance of 96 percent accuracy and 95 percent κ coefficient, thus exhibiting promising potentials for real-world applications.

This paper aims to present the design and implementation of a circularly polarized co-planar waveguide (CPW) fed wideband pie-shaped monopole antenna for multi-antenna techniques. Multi-antenna techniques are promising solutions for higher data rate and enhanced reliability of wireless applications. They find numerous applications in 4G/5G networks and in most wireless standards such as wireless local area networks (WLAN), wireless fidelity and worldwide interoperability for microwave access systems to enhance the channel capacity without additional spectrum by means of multi-path propagation techniques.

The antenna is designed to operate at three WLAN frequency bands of 4.8, 5.2 and 5.8 GHz. The measured 10 dB impedance bandwidth of the proposed antenna element is 1.2 GHz (24.23 per cent). The proposed CPW fed, pie-shaped monopole antenna has a gain of 5.4 dB and an efficiency of 72.8 per cent at 4.8 GHz.

To use the proposed antenna in a multi-antenna environment, the antennas have to be placed in a close proximity to each other. The close proximity introduces strong mutual coupling between the antennas, which in turn degrades the performance of multi-antenna systems. A multi-antenna system with two antenna elements has been constructed with an edge to edge spacing of 0.24 λ₀ (15 mm), and the mutual coupling level is −17 dB. To enhance the isolation between the antenna elements, a shorting pin-based interconnected semicircles enclosed decoupling structure is proposed, which improves the isolation by a factor of 12.67 dB at 4.8 GHz.

To validate the performance of the proposed multi-antenna in working environment, the performance metrics such as envelope correlation coefficient (ECC), diversity gain (DG) and total active reflection coefficient (TARC) are computed for the proposed multiple-input multiple-output (MIMO) antenna. The ECC value is 0.000366 at center frequency and below 0.09 for the entire operating bandwidth, which is well below the acceptable level of 0.5 as per 3GPP standard. The DG value lies above 9.5 dB for the entire operating bandwidths and it is well above the minimum value of 3 dB. The TARC values are calculated based on S parameters, and it proves that the proposed antenna a good candidate for the multi-antenna systems.

Based on the theory of planned behavior (TPB) and stakeholder theory, the model proposes that responsible leadership (RL) is mediated by affective commitment (AC) on both outcome variables (organizational citizenship behavior [OCB] and patient satisfaction [PS]) while distributive justice (DJ) moderates the relationship among RL, OCB and PS through the mediator of AC.

Overall, data collected from 275 employees and patients in India’s healthcare sector support this model both in online and offline mode. SPSS 25, AMOS 22 and PROCESS macro were used to analyze the data.

The influence of RL, OCB and PS was seen insignificant in the Indian healthcare sector. This study examines the role of AC as a mediator which does not affect extra-role behavior and PS. The findings also show that the moderation-mediation effect of DJ through AC strengthened the link between RL and OCB, but not PS. Commitment does not affect extra-role behavior and PS.

Until now, there has been no research in the Indian context that has tested the effect of RL on extra-role behaviors and PS, as mediated by AC, according to researchers’ knowledge. Since RL and outcome variables are related through AC, the current study aims to understand how DJ acts as a moderator to that relationship.

Intangible cultural heritage products (ICHP) in this paper refer to the products made with handicrafts listed as intangible cultural heritage. The purpose of this paper is to examine the effects of consumer cultural identity and consumer knowledge on purchase intentions of ICHP, as well as the role of the perceived scarcity for such effects.

Three between-participants experiments were conducted to investigate the effect of cultural identity on purchase intention of ICHP and the underlying mechanism of the effect.

The results show that cultural identity has a positive influence on ICHP purchase intention, and this effect is stronger for consumers with higher level of consumer knowledge. Furthermore, perceived scarcity underlies such effect, but the scarcity account holds only for handmade ICHP, not for machine-manufactured products.

The current research suggests that ICHP should remain handmade to preserve their scarcity as a distinctive feature. Additionally, business practitioners handling ICHP should target consumers of high cultural identity, and/or provide iconic cues to activate their cultural identity situationally. Furthermore, it highlights the importance of consumer education programs about ICHP-related knowledge in enhancing the cultural identity effect.

This paper explores systematically the conditions and process of consumers' responses toward ICHP for the first time. Besides, it builds on accessibility-diagnosticity framework and provides novel knowledge about the functioning of consumer cultural identity. It also enriches our understanding of perceived scarcity from the supply side.

This study aims to consider the influence of density difference integral and relative flow difference on traffic flow, a novel two-lane lattice hydrodynamic model is proposed. The stability criterion for the new model is obtained through the linear analysis method.

The modified Korteweg de Vries (KdV) (mKdV) equation is derived to describe the characteristic of traffic jams near the critical point. Numerical simulations are carried out to explore how density difference integral and relative flow difference influence traffic stability. Numerical and analytical results demonstrate that traffic congestions can be effectively relieved considering density difference integral and relative flow difference.

The traffic congestions can be effectively relieved considering density difference integral and relative flow difference.

Novel two-lane lattice hydrodynamic model is presented considering density difference integral and relative flow difference. Applying the linear stability theory, the new model’s linear stability is obtained. Through nonlinear analysis, the mKdV equation is derived. Numerical results demonstrate that the traffic flow stability can be efficiently improved by the effect of density difference integral and relative flow difference.

This paper aims to put forward an extended lattice hydrodynamic model, explore its effects on alleviating traffic congestion and provide theoretical basis for traffic management departments and traffic engineering implementation departments.

The control method is applied to study the stability of the new model. Through nonlinear analysis, the mKdV equation representing kink-antikink soliton is acquired.

The predictive effect and the control signal can enhance the traffic flow stability and reduce the energy consumption.

The predictive effect and feedback control are first considered in lattice hydrodynamic model simultaneously. Numerical simulations demonstrate that these two factors can enhance the traffic flow stability.