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Using wire as feedstock has several advantages for additive manufacturing (AM) of metal components, which include high deposition rates, efficient material use and low material costs. While the feasibility of wire-feed AM has been demonstrated, the accuracy and surface finish of the produced parts is generally lower than those obtained using powder-bed/-feed AM. The purpose of this study was to develop and investigate the feasibility of a fine wire-based laser metal deposition (FW-LMD) process for producing high-precision metal components with improved resolution, dimensional accuracy and surface finish.

The proposed FW-LMD AM process uses a fine stainless steel wire with a diameter of 100 µm as the additive material and a pulsed Nd:YAG laser as the heat source. The pulsed laser beam generates a melt pool on the substrate into which the fine wire is fed, and upon moving the X–Y stage, a single-pass weld bead is created during solidification that can be laterally and vertically stacked to create a 3D metal component. Process parameters including laser power, pulse duration and stage speed were optimized for the single-pass weld bead. The effect of lateral overlap was studied to ensure low surface roughness of the first layer onto which subsequent layers can be deposited. Multi-layer deposition was also performed and the resulting cross-sectional morphology, microhardness, phase formation, grain growth and tensile strength have been investigated.

An optimized lateral overlap of about 60-70% results in an average surface roughness of 8-16 µm along all printed directions of the X–Y stage. The single-layer thickness and dimensional accuracy of the proposed FW-LMD process was about 40-80 µm and ±30 µm, respectively. A dense cross-sectional morphology was observed for the multilayer stacking without any visible voids, pores or defects present between the layers. X-ray diffraction confirmed a majority austenite phase with small ferrite phase formation that occurs at the junction of the vertically stacked beads, as confirmed by the electron backscatter diffraction (EBSD) analysis. Tensile tests were performed and an ultimate tensile strength of about 700-750 MPa was observed for all samples. Furthermore, multilayer printing of different shapes with improved surface finish and thin-walled and inclined metal structures with a minimum achievable resolution of about 500 µm was presented.

To the best of the authors’ knowledge, this is the first study to report a directed energy deposition process using a fine metal wire with a diameter of 100 µm and can be a possible solution to improving surface finish and reducing the “stair-stepping” effect that is generally observed for wires with a larger diameter. The AM process proposed in this study can be an attractive alternative for 3D printing of high-precision metal components and can find application for rapid prototyping in a range of industries such as medical and automotive, among others.

This study aimed to facilitate a rapid evaluation of track service status and vehicle ride comfort based on car body acceleration. Consequently, a low-cost, data-driven approach was proposed for analyzing speed-related acceleration limits in metro systems.

A portable sensing terminal was developed to realize easy and efficient detection of car body acceleration. Further, field measurements were performed on a 51.95-km metro line. Data from 272 metro sections were tested as a case study, and a quantile regression method was proposed to fit the control limits of the car body acceleration at different speeds using the measured data.

First, the frequency statistics of the measured data in the speed-acceleration dimension indicated that the car body acceleration was primarily concentrated within the constant speed stage, particularly at speeds of 15.4, 18.3, and 20.9 m/s. Second, resampling was performed according to the probability density distribution of car body acceleration for different speed domains to achieve data balance. Finally, combined with the traditional linear relationship between speed and acceleration, the statistical relationships between the speed and car body acceleration under different quantiles were determined. We concluded the lateral/vertical quantiles of 0.8989/0.9895, 0.9942/0.997, and 0.9998/0.993 as being excellent, good, and qualified control limits, respectively, for the lateral and vertical acceleration of the car body. In addition, regression lines for the speed-related acceleration limits at other quantiles (0.5, 0.75, 2s, and 3s) were obtained.

The proposed method is expected to serve as a reference for further studies on speed-related acceleration limits in rail transit systems.

Risk parity, also known as equal risk contribution, has recently gained increasing attention as a portfolio allocation method. However, solving portfolio weights must resort to numerical methods as the analytic solution is not available. This study improves two existing iterative methods: the cyclical coordinate descent (CCD) and Newton methods. The authors enhance the CCD method by simplifying the formulation using a correlation matrix and imposing an additional rescaling step. The authors also suggest an improved initial guess inspired by the CCD method for the Newton method. Numerical experiments show that the improved CCD method performs the best and is approximately three times faster than the original CCD method, saving more than 40% of the iterations.

The current study implies self-quantification to consumer behavior and investigates how self-quantification influences consumers' persistence intentions, then indicates the underlying mechanism and examines the role of sharing in social media context.

The hypotheses are tested by three experimental studies. In study 1, the authors test the main effect of self-quantification on persistence intentions and demonstrate goal specificity as the mediator. In study 2 and 3, the authors explore sharing and sharing audience as the moderators.

The current research demonstrates that quantifying personal performance increases consumers' persistence intentions because self-quantification makes the focal goal more specific. However, sharing self-quantification performance with others has a negative effect on the relationship between self-quantification and persistence intentions. Building on goal conflict theory, sharing diverts consumers' focus away from the goal itself and toward others' evaluation and judgment, which makes the focal goal more ambiguous. Moreover, the negative effect depends on who is the sharing audience. When consumers share with close others who hold a similar goal with them, the negative effect of sharing is dramatically reversed.

The present research offers guidelines to managers about how to design self-tracking system to increase user's engagement and how to establish social community on social media platform to motivate users' goal pursuit.

This study contributes to the research of self-quantification from consumer behavior perspective. It also enriches interactive marketing literature by broadening self-quantification relevant research from social interaction dimension.

Two time metaphors are often adopted to express the passage of time: the ego-moving metaphor that conceptualizes the ego as moving toward the stationary event (e.g. we are approaching the holiday) or the event-moving metaphor that conceptualizes the event as moving toward the stationary ego (e.g. the holiday is approaching us). This paper aims to investigate the influence of the time metaphor on regulatory focus, as well as its downstream marketing implications.

Five studies were conducted. Studies 1a–1c examined the moderating effect of the valence of events on the relationship between time metaphors and regulatory focus. Studies 2–3 investigated the downstream marketing implications of the above effects.

The findings indicated that compared to the event-moving metaphor, the ego-moving metaphor is more likely to evoke a promotion focus when consumers anticipate a positive event. However, when the event is negative, the ego-moving metaphor is more likely to evoke a prevention focus compared to the event-moving metaphor.

This research extends the previous literature on regulatory focus activation by showing that time metaphors affect regulatory focus, and that event valence plays a critical moderating role in the relationship.

Many companies rely on positive events (e.g. holidays, anniversaries) to market their products. The findings of this research suggest that companies promoting products with promotion-related benefits or products with higher risks should adopt an ego-moving metaphor to describe the coming of the event. In contrast, companies promoting products with prevention-related benefits or products with low risks should adopt an event-moving metaphor to describe the coming of the event.

This research showed that the effects of time metaphors on consumers’ regulatory focus depend on the valence of the events. It also demonstrated the downstream implications of time metaphors by showing that time metaphors influence consumer product choices and financial decisions.

The correlations and deviations between market prices, production prices and values are critical indexes for testing the labor theory of value. However, there is not yet a universally accepted method of solving for the production price vector, and given the complexity and volatility of economic dynamics, production prices based on the assumption of economic equilibrium cannot be accurate measuring. This paper attempts to propose a new approach to test the labor theory of value.

This paper proposes a different approach. From the perspective of disequilibrium price, the paper deduces that the range of the relative prices of commodities is determined by the relative value, the rate of surplus-value and the technical structure of production inputs, with relative price fluctuating within the value range specified by the labor theory of value under market competition influences.

With empirical research results based on China’s economic data, this paper not only affirms the scientific and practical explanatory power of the labor theory of value in a more general sense but also uncovers how surplus value is distributed across sectors, which can be used to analyze market competition and technical relations and their impacts on industrial structure and distribution.

The disequilibrium analytical framework provides a new perspective for the empirical study of labor theory of value. Moreover, it evolves the labor theory of value into a robust empirical framework, breaking through the theoretical path of the traditional labor theory of value that is mostly limited to the normative discussion of exploitation.

The purpose of this paper is to formulate and solve a last-mile distribution plan problem with concern for the quality of fruits and vegetables in cold chains.

The vehicle routing problem with time windows (VRPTW) is extended based on the characteristics of fruit-and-vegetable cold chains. The properties of multiple perishable foods, continuing decline in quality, various requirements for quality levels and optimal temperature settings during vehicle transportation are considered in the VRPTW. The product quality level is defined by the estimation of residual shelf life, which changes with temperature, and is characterized by a stepped decrease during the transportation process as time goes on. A genetic algorithm (GA) is adapted to solve the problem because of its convincing ability to solve VRPTW-related problems. For this purpose, solution encoding, a fitness function and evolution operators are designed to deal with the complicated problem herein.

A distribution plan including required fleet size, vehicle routing sequence and what quality level should be shipped out to account for the quality degradation during vehicle transportation is generated. The results indicate that the fulfillment of various requirements of different customers for various fruits and vegetables and quality levels can be ensured with cost considerations.

This study presents a problem for last-mile delivery of fresh fruits and vegetables which considers multiple practical scenarios not studied previously. A solution algorithm based on a GA is developed to address this problem. The proposed model is easily applied to other types of perishable products.

Despite the stimulation provided by market demand and green issues on business performance, the exact nature of the relationships among these aspects remains an issue of contention. This study sought to bridge this gap in the research by examining the effects of market demand on firm performance using green innovation and environmental performance as mediators. The paper aims to discuss these issues.

The Taiwanese hybrid vehicle industry was targeted as the scope of research. Using random sampling method, survey questionnaires were distributed to retailers, wholesalers, and component sale firms in the industry through post and e-mails. AMOS 5.0 and the structural equation modeling (SEM) were used to test the hypotheses and the theoretical model.

Except for the impact of market demand on environmental performance, all relationships were found to be significant. The mediating effect of green innovation which was proven to be significant, while that of environmental performance remained insufficient.

This study has a number of limitations. The use of figures from a single industry partly restricts the generalizability of these findings.

These results suggest that firms should make greater efforts to understand customer needs and promote core competencies in the innovation of green products and processes to align green initiatives with consumer values in order to satisfy market demand and ensure sustainable performance.

This study has important implications for the hybrid vehicle industry in particular and all businesses in general. The results provide guidelines for the enhancement of business performance. Based on the significant impact of market demand on green innovation, this study strongly recommends that firms make greater efforts to understand customer needs and expectations.

This study was the first to establish a model for investigating the links among market demand, green innovation, environmental performance, and firm performance in the Taiwanese hybrid vehicle industry. The findings provide effective guidelines for the achievement of market leadership and sustainable performance.

The impact of event quality on expenditure and visitors’ loyalty has been an issue seldom analyzed by festival literature. These same incidental relations were not assessed from a temporary perspective in the case of recurrent cultural events. This paper aims to explore these causal relationships and to report on the moderation effect of the temporary inquiry on the editions of the festival.

Nine hypotheses were examined through squares SEM techniques, and the model validation was carried out by assessing the measurement and structural model. In addition, a multi-group analysis was performed to test the temporary moderation effect. Finally, a survey was applied during three successive editions (2013 = 164 cases, 2014 = 154 cases, 2015 = 128 cases).

The local and ephemeral nature of the festival favors immediate consumption, and the budget share increase among categories passes through diversification to stimulate purchases. In this particular context, the moderation induced by the sequence of editions had a conclusive impact on the analyzed relationships, generating the need to focus on the temporary variability to understand and operate the recurrent events.

The strengthening of the festival went through a stage where it opened to other segments of visitors despite the dominant opinion to preserve the local character of the event. In addition, this study clarifies that a retrospective analysis of previous editions, when compared to the stationarity perspective of the festival, allows a better understanding of the required upgrading to preserve visitor loyalty.

El impacto de la calidad del evento en el gasto y la lealtad de los visitantes ha sido un tema pocas veces analizado por la literatura de los festivales. Estas mismas relaciones incidentales no fueron valoradas desde una perspectiva temporal en el caso de eventos culturales recurrentes. El artículo explora estas relaciones causales e informa sobre el efecto moderador de la investigación longitudinal de las ediciones del festival.

Se examinaron nueve hipótesis a través de técnicas de cuadrados MES, y la validación se llevó a cabo mediante la evaluación del modelo estructural y de medición. Además, se realizó un análisis multigrupo para probar el efecto de moderación longitudinal. Los datos analizados provienen de encuestas aplicadas durante tres ediciones sucesivas (2013 = 164 casos, 2014 = 154 casos, 2015 = 128 casos).

El carácter local y efímero del evento favorece el consumo inmediato, y el aumento de la participación en el gasto entre categorías pasa por la diversificación que permite estimular la compra. En este contexto particular, la moderación inducida por la secuencia de ediciones incidió contundentemente en las relaciones analizadas, generando la necesidad de prestar atención a los cambios temporales para comprender y operar los eventos recurrentes.

El fortalecimiento del festival pasó por una etapa donde se abrió a otros segmentos de visitantes a pesar de la opinión dominante de preservar el carácter local del evento. Además, este estudio aclara que un análisis retrospectivo de ediciones anteriores, en comparación con la perspectiva de la estacionariedad del evento, permite gestionar la actualización necesaria que permite preservar la lealtad del visitante.

Promoting electric vehicles (EVs) is an effective way to achieve carbon neutrality. If EVs are widely adopted, this will undoubtedly be good for the environment. The purpose of this study is to analyze the impact of network externalities and subsidy on the strategies of manufacturer under a carbon neutrality constraint.

In this paper, the authors propose a game-theoretic framework in an EVs supply chain consisting of a government, a manufacturer and a group of consumers. The authors examine two subsidy options and explain the choice of optimal strategies for government and manufacturer.

First, the authors find that the both network externalities of charging stations and government subsidy can promote the EV market. Second, under a relaxed carbon neutrality constraint, even if the government’s purchase subsidy investment is larger than the carbon emission reduction technology subsidy investment, the purchase subsidy policy is still optimal. Third, under a strict carbon neutrality constraint, when the cost coefficient of carbon emission reduction and the effectiveness of carbon emission reduction technology are larger, social welfare will instead decrease with the increase of the effectiveness of emission reduction technology and then, the manufacturer’s investment in carbon emission reduction technology is lower. In the extended model, the authors find the effectiveness of carbon emission reduction technology can also promote the EV market and social welfare (or consumer surplus) is the same whatever the subsidy strategy.

The network externalities of charging stations and the subsidy effect of the government have a superimposition effect on the promotion of EVs. When the network effect of charging stations is relatively strong, government can withdraw from the subsidized market. When the network effect of charging stations is relatively weak, government can intervene appropriately.

Comparing previous studies, this study reveals the impact of government intervention, network effects and carbon neutrality constraints on the EV supply chain. From a sustainability perspective, these insights are compelling for both EV manufacturers and policymakers.