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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jbusres.2007.11.008 Byline: Pei-Chun Lin Keywords: Optimal pricing; Sales rate; Profit system; Revised profit model Abstract: This study investigates the marketing and production problem for a monopolist firm where price, quality and production rate are simultaneous dynamic decision variables under the condition of a dynamic demand that depends on price, quality and cumulative sales. The formulated continuous profit maximization model follows the steps for dynamic optimization to derive optimal price, quality and production policies, wherein a unit production cost that decreases with cumulative production reflects the cost learning effect. Through the differentiable multiplicatively separable demand function, this study analyzes optimal trajectories for determining price, quality, and production rate. The results specify several optimal policies and policy makers would gain insight into the consequence of their decisions that otherwise might have been obscured by sub-optimal analysis. Author Affiliation: National Cheng Kung University, Department of Transportation and Communication Management Science, 701, Taiwan Article History: Received 1 March 2007; Revised 1 August 2007; Accepted 1 November 2007 Article Note: (footnote) [star] The author gratefully acknowledges the helpful comments of the editor and the reviewers. This work was supported in part by the National Science Council of the Republic of China in Taiwan under grants NSC 93-2213-E-327-011.

This study collected the annual revenue data of the top three supermarket chains in Taiwan (PX Mart, Simple Mart, and Wellcome), shopping frequency in supermarkets, and the average expenditure of the general public in order to construct models for simulating supermarket revenue by calibrating model parameters to the actual data. This study employed the competing destinations model (CDM) to designate supermarket shoppers' shopping areas and simulate supermarket sales. The CDM calculated the probability of consumers selecting each supermarket, simulated the total revenues of supermarkets and the average daily revenue of a single store using the expenditure equation, and added spatial competition and agglomeration effect parameters to the model to observe variations in revenue with changing parameter values. The study results revealed profitable expansion opportunities and highly competitive locations not advised for new outlets. Beitou district had the lowest population density in Taipei City yet a high-sales cluster, making it an area suitable for new PX Mart stores. Shilin and Xinyi districts could also be considered suitable areas for new stores because they had insignificant distributions of stores, high-sales clusters, and competition was not yet severe. The study extends the use of analytical revenue and spatial models to empirically study the agglomeration forces between supermarket chains, analyzes the influence of distance variation on supermarket revenues, and determines the most suitable locations for the future inauguration of supermarket stores in Taipei City. • This study collected the annual revenue data of the top three supermarket chains in Taiwan. • The agglomeration forces between supermarket chains were investigated. • This study constructed models for simulating supermarket revenue by calibrating parameters to the actual data. • The study analyzed the influence of distance variation on supermarket revenues. • The study results revealed profitable expansion opportunities. [ABSTRACT FROM AUTHOR]

The study examined how bus and taxi drivers’ public self-consciousness interacted with social anxiety to influence their aberrant driving behaviors. Questionnaires were distributed to 331 male and female Taiwanese bus and taxi drivers whose working environment involves frequent and direct interaction with passengers. Questionnaire statements measured drivers’ dispositional public self-consciousness and social anxiety, and their intentions and driving behaviors related to speeding, errors and violations. The study utilized a mediating model and path analysis explored causal relationships between the constructs. The study found that both public self-consciousness and social anxiety explained bus drivers’ aberrant driving behaviors. Female drivers reported less aberrant driving behaviors than their male counterparts did. Bus drivers reported less aberrant driving behaviors than taxi drivers. Drivers with crash involvement within three years reported higher public self-consciousness than did those without that involvement. The suitable research frameworks, which describe the influence of public self-consciousness and social anxiety on aberrant driving behaviors, fit to bus and taxi drivers are different, so as different to male and female drivers. The study findings suggest bus and taxi driver should receive special training in general attitude as a condition of their employment in order to avoid aggressive behaviors and provide a better and safer service to the public. [ABSTRACT FROM AUTHOR]

This research investigates the number of on-time flights (OTFs) at European airports and how this number is influenced by an airport's flight connectivity. We conduct a spatial statistical analysis of the spatial context relationship using econometric models, and the interaction between the number of airport's on-time flights (OTFs) and flight connectivity. Using 2017 and 2018 data, we characterize the relationship between a European airport's air connectivity index (ACI) and the number of flights that depart or arrive at a gate within 15 min of schedule (OTFs). We also analyze the relationship between OTFs at a given airport and those of neighboring airports. As the distances between airports increase, autocorrelation shifts from a positive to a negative sign meaning that at greater distances, airports' on-time performance is less dissimilar. We find that before the pandemic and the ensuing global travel shutdown, a spatially lagged term of ACI improves the model's ability to account for variations in OTFs across airports. Flight delay propagation in the air transport system caused delays to occur due to the shared resources underlying an initially delayed flight and subsequent flights. This analysis offers a rational for increasing airport connectivity as a way of improving the share of on-time flights of European airports. • The study conducts a spatial statistical analysis of the interaction between the number of European airport's on-time flights and connectivity. • The on-time performance of European airports is close to their neighboring airports. • As the distances between airports increase, airports' on-time performance is less dissimilar. • The highest spatial autocorrelation values exist between European airports within 110 km of one another. [ABSTRACT FROM AUTHOR]

Recent changes in the world economy have had a significant impact on container shipping in recent decades. A growing number of studies have demonstrated that service capabilities are related to competitive advantage and organizational performance. When encountering an environment characterized by economic uncertainty, the shipping industry was required to emphasize dynamic capabilities associated with adaptation to sustain competitive advantage. The purpose of this study was to examine the linkages between dynamic capabilities, service capabilities, competitive advantage, and organizational performance in container shipping using data surveys from 134 respondents in container shipping firms in Taiwan. Exploratory factor analysis was employed to identify the crucial dimensions underlying dynamic capabilities, and service capabilities. Furthermore, structural equation modeling (SEM) was used to test the research hypotheses. The research findings indicated that dynamic capabilities positively influenced both competitive advantage and service capabilities. Service capabilities and competitive advantage were positively related to organizational performance. Practical implications of the research findings for container shipping firms are discussed. [ABSTRACT FROM AUTHOR]

Highlights: [•] This study assesses the Combined Heat and Power Economic Dispatch (CHPED) problem. [•] The study investigated the performances of an evolutionary computing approach, HSGA. [•] The results show that the algorithm yields high-quality solutions for the CHPED. [ABSTRACT FROM AUTHOR]

Highlights: [•] This study integrated gender with the interface of car navigation systems (CNSs) to analyze the usability of CNS interfaces. [•] A combination of gender and the interface dimension design affects CNS objective usability. [•] Gender differences affect CNS objective and subjective usability. [•] Differences in operational performance between the two gender groups were less using 2D interface than using 3D interface. [•] Different interface designs of CNS brands affect CNS objective usability. [ABSTRACT FROM AUTHOR]

Highlights: [•] HYS-32 is a new analogue of combretastatin A-4 containing a cis-stilbene moiety. [•] We investigate the effect of HYS-32 on Cx43 gap junctions in rat primary astrocytes. [•] HYS-32 enhances Cx43 expression and GJIC via a PKC–ERK signaling cascade. [•] HYS-32 prevents LPS-induced downregulation of Cx43 and inhibition of GJIC. [•] The effects of HYS-32 on astrocytes potentiate its application in neuroprotection. [Copyright &y& Elsevier]

Abstract: This study investigates stress-influence factors perceived by military aircrews undergoing centrifuge training, which lowers the incidence of G-induced loss of consciousness (G-LOC) for the crews of high-performance combat aircrafts. We used questionnaires to assess the subjective stress-influence factors of crews undergoing centrifuge training. Professionals in aviation physiology identified attributes measuring the perceived stress induced by centrifuge training, which were segmented into three constructs by factor analysis, theory lecture, centrifuge equipment, and physical fitness. Considerable interpenetration was discernible between these factors and military rank, age, length of service, flight hours accrued, and type of aircraft piloted. Identifying and quantifying the perceived stressors experienced in human-use centrifuge training enables aviators, astronauts, and air forces of the world to determine which constructs perceptibly increase or alleviate the perceived stress undergone by trainees when partaking in centrifuge training. [Copyright &y& Elsevier]

Abstract: This study applies the theory of consumption values to determine the influence factors on consumer choice behavior regarding green products, and examines whether there are significant differences in consumption values and choice behavior between consumers with different outlooks on environmental concerns. One-way analysis of variance and multiple regression is used to assess data collected by a questionnaire survey. The results indicate that consumers with high environmental concern support green products more, and show greater readiness to choose them. This study concludes that the main influence factors on consumer choice behavior regarding green products include psychological benefit, desire for knowledge, novelty seeking, and specific conditions, and do not include functional values, price and quality. This study contributes to preliminary but vital insights in effective promotion of green products. [Copyright &y& Elsevier]

Abstract: This paper addresses an integrated model that schedules multi-item replenishment with uncertain demand to determine delivery routes and truck loads, where the actual replenishment quantity only becomes known upon arrival at a demand location. This paper departs from the conventional ant colony optimization (ACO) algorithm, which minimizes total travel length, and incorporates the attraction of pheromone values that indicate the stockout costs on nodes. The contributions of the paper to the literature are made both in terms of modeling this combined multi-item inventory management with the vehicle-routing problem and in introducing a modified ACO for the inventory routing problem. [Copyright &y& Elsevier]

Recent reports on environmental protection have found that lean management can facilitate green operations in container terminals. Using data from 268 samples in Kaohsiung, a structural equation modeling approach was employed to examine the relationships among lean management, green operations, and green behavior with respect to green performance, and a hierarchical regression approach was utilized to test the moderating effect of green climate between these major dimensions in the context of container terminals. The research findings indicated that lean management positively influenced both green operations and green behavior. Green operational practices had a positive impact on both green behavior and green performance. Green climate also had a positive effect on green performance. Additionally, a green climate positively moderated the effect of lean management, green behavior, and green performance. In this era of environmental protection, these research outcomes have practical implications for the expansion of container terminal organizations by improving operational effectiveness with green performance. [ABSTRACT FROM AUTHOR]

Carbon mitigation strategies are an urgent and overdue tourism industry imperative. The tourism response to climate action has been to engage businesses in technology adoption, and to encourage more sustainable visitor behaviour. These strategies however are insufficient to mitigate the soaring carbon footprint of tourism. Building upon the concepts of optimization and eco-efficiency, we put forward a novel carbon mitigation approach, which seeks to pro-actively determine, foster, and develop a long-term tourist market portfolio. This can be achieved through intervening and reconfiguring the demand mix with the fundamental aim of promoting low carbon travel markets. The concept and the analytical framework that quantitatively inform optimization of the desired market mix are presented. Combining the "de-growth" and "optimization" strategies, it is demonstrated that in the case study of Taiwan, great potential exists to reduce emissions and sustain economic yields. The implications for tourism destination managers and wider industry stakeholders are discussed. • Optimizing the demand mix to promote low carbon travellers has a great potential for carbon mitigation. • A methodological and analytical framework is presented to inform optimization of the desired market mix. • Combining the "de-growth" and "optimization" strategies is an efficient approach to reduce CO2 and sustain economic yields. • Destinations are encouraged to pro-actively determine, foster, and develop a long-term tourist market portfolio. [ABSTRACT FROM AUTHOR]

Abstract: This study ranked the significant threats and human errors affecting aviation safety. Two-phase questionnaires were used to elicit experts'' views on four categories of human errors and threats comprising twenty-three criteria. The analytical hierarchy process was used to calculate the weight for each criteria which were then ranked in order of importance. The study indicated that flight crew errors are the most important threats. [Copyright &y& Elsevier]

In order to turn Taipei into a sustainable, green metropolis, in 2009, the Department of Transportation of Taipei City Government launched a public bike rental system (YouBike) to meet people’s daily commute and/or leisure needs. Given that users may return bikes to sites differing from their starting locations, rental stations frequently lack bikes or bike racks. This study sought to identify lacking-bike and/or lacking-bike rack hot spots utilizing spatial-temporal analysis. In addition, it applied retail location theory to determine site selection of further rental stations. Historical data indicated that shortage of bikes was much more severe than shortage of bike racks in the YouBike public bike system and lacking-bike and lacking-bike rack hot spots were clustered significantly. The study demonstrated that spatial-temporal analysis can be used to effectively identify rental stations’ spatial patterns, determine the most suitable locations for further installation of rental stations, help to provide public bike users with a more effective rental system, and greatly assist public bikes’ operational management and decision-making in Taiwan. [ABSTRACT FROM AUTHOR]

• Developing a novel 2-DOF spherical joint with a large continuously rotatable range. • Using a C-shaped rail mechanism to avoid collision and to enlarge workspace. • Developing a dynamic model of the joint for behavioral analysis. • Building a prototype of the joint, and experimentally confirming the functionality of the joint. The development of an innovative two-degrees-of-freedom (2-DOF) active spherical joint (universal joint) that can provide an extended range of motion and perform continuous rotation in both DOFs is reported. The workspace of the 2-DOF joint in general arrangements is explored. To overcome the structural limitation of the general configurations of the joint, this work proposes a new design that incorporates rotatable C-shaped rails to avoid collision among components of the joint. The dynamic model of the 2-DOF joint is constructed, and its behaviors in the simulation are analyzed. The trajectories are generated in simulation to better understand the joint torque requirement. A prototype of the 2-DOF joint was fabricated, and its performance was experimentally evaluated. The experimental results confirm that the continuous rotation of the two DOFs in a wide range is feasible and that the RMSEs of positions were less than 2% within the motion range, and those of orientations were less than 0.6% along the entire rotations, with standard deviations under 0.4 mm and 0.6 degree. [ABSTRACT FROM AUTHOR]

This study aims to quantify the environmental impact of two retail distribution networks and offer consumers a channel that is more beneficial to the environment. The environmental impact of replenishing the packaged beverages sold in convenience stores (CVSs) and hypermarkets is assessed using the streamlined life-cycle assessment (LCA) approach. In this study, the life-cycle impact assessment (LCIA) for packaged beverages up to the point of sale illustrates the distribution-level environmental impacts of truck transportation. The matched-pair t -test shows that the environmental impacts of transporting 1800 cartons of 24-pack/10 oz. beverages to be sold in Carrefour and 7-11 stores is different at a significance level of 0.1. The transport-focused LCA is used to improve the understanding and compare the environmental characteristics of the two distribution and retail systems. This study constitutes a vehicle for communicating to both internal and external stakeholders the environmental profiles of distributing the same product sold through two retail channels. [ABSTRACT FROM AUTHOR]

Abstract: This study employed a two-phase methodology to assess the environmental impacts from offset lithographic printing on color-box packaging. The Analytic Hierarchy Process (AHP) was used to prioritize improvement options and the life-cycle assessment (LCA) approach was used to assess environmental impacts quantitatively. This study quantified the total amount of energy consumption and CO2 emissions caused by the printing processes of color-box packaging and showed that the total reduction of GHG emissions of the system that omitted the laminating and varnishing process was approximately 239 kg. Moreover, incineration contributes 2905–3004 kg of CO2 to potential global warming in the case of color-box packaging. The study demonstrated the viability of the AHP for evaluating environmental impacts of printing processes, ranking them in order of pollution potential, and subsequently identifying those critical for reducing environmental pollution on the printing operation. This study also showed how the LCA approach may be used together with expert opinion to identify opportunity to alter printing processes in order to address environmental impacts and improve the environmental profile of offset lithographic printing. [Copyright &y& Elsevier]

This study tested key predictions of confusion, which accompanies a state of cognitive conflict triggered by erroneous Chinese characters, for students to detect and correct in an online Chinese reading-correcting game competition. In addition, this study examined how participants' concepts of human intelligence could predict whether they maintained their levels of gameplay anxiety and reflected their intention to join the competition as mediated by epistemic curiosity. There were 189 sixth-grade students who returned the questionnaires, and the results revealed that the incremental theory of language intelligence could predict 2 types of epistemic curiosity (EC): D-type EC was positively correlated to gameplay anxiety, while I-type EC was not significantly associated with gameplay anxiety. Moreover, gameplay anxiety was positively correlated with intention to join the contest. The implication of these findings is that teachers may use scaffolding with a positive effect on incremental theory of language intelligence to encourage students to have more EC. [ABSTRACT FROM AUTHOR]

The spliceosome is formed on pre-mRNA substrates from five small nuclear ribonucleoprotein particles (U1, U2, U4/U6 and U5 snRNPs), and numerous non-snRNP factors. Saccharomyces cerevisiae U4/U6.U5 tri-snRNP comprises U5 snRNA, U4/U6 snRNA duplex and approximately 30 proteins and represents a substantial part of the spliceosome before activation. Schizosaccharomyces pombe U2.U6.U5 spliceosomal complex is a post-catalytic intron lariat spliceosome containing U2 and U5 snRNPs, NTC (nineteen complex), NTC-related proteins (NTR), U6 snRNA, and an RNA intron lariat. Two recent papers describe near-complete atomic structures of these complexes based on cryoEM single-particle analysis. The U4/U6.U5 tri-snRNP structure provides crucial insight into the activation mechanism of the spliceosome. The U2.U6.U5 complex reveals the striking architecture of NTC and NTR and important features of the group II intron-like catalytic RNA core remaining after spliced mRNA is released. These two structures greatly advance our understanding of the mechanism of pre-mRNA splicing. [ABSTRACT FROM AUTHOR]

• Development of a spherical robot that can leap while rolls. • Using a five-bar linkage mechanism and a release/retract mechanism for leaping. • Using a differential drive to actuate two semi spheres for rolling and turning. • Dynamics of rolling and leaping are analyzed. • The robot can leap up to 1.14-times of radius to overcome a barrier while rolls. To improve robots' mobility on flat ground and rough terrain, we designed and implemented a novel spherical robot with a combined rolling and leaping capability. The robot has two individually driven semi-spheres, which generate rolling and turning motions. The robot also has a five-bar linkage with a release/retract mechanism for leaping. The release/retract mechanism only uses one DOF to control and switch the mechanism in three different stages: retracting, maintaining, and releasing. In this paper, the dynamics of the robot in rolling and leaping are analyzed. The robot was empirically built, and its performance was experimentally evaluated. The results confirm that the robot can leap close to 25.4 cm diameter of the sphere, which, to the best of our knowledge, is the best among reported spherical robots. The robot can also leap while rolling over a 14 cm barrier, which is equal to 1.14 times the sphere's radius. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: We designed and implemented a novel omnidirectional spherical robot. Instead of using wheels or flywheels, a driven ball is installed inside the spherical shell and driven by two orthogonally-mounted rollers; thus, the omnidirectional mobility of the robot with no singularity can be achieved by simple forward kinematic mapping. The dynamic model of the robot is derived, and effect of the model's parameters is evaluated in simulation and discussed. The simulation results also serve as the design guideline for building the empirical system. Several design issues are addressed to ensure the robot's proper development. Finally, the spherical robot is built, and its performance is quantitatively and experimentally evaluated, thus proving its omnidirectional and trajectory-controllable mobility. [Copyright &y& Elsevier]

• A novel module capable of fast transforming its shape between a wheel and a leg. • The maximum leg length approximately 3.4 times the wheel radius. • Can perform wheel-to-leap behavior. • Leaping height up to 4.6 times the wheel radius. We report on the development of a novel two-degrees-of-freedom module capable of transforming its shape between a wheel and a leg, with the length of the latter approximately 3.4 times the wheel radius. The leg-wheel module was empirically built and experimentally evaluated. It utilizes a linkage mechanism and can perform a smooth yet rapid leg-wheel transition within 0.25 s. The design concept, selection of the linkage parameters, and kinematics are described in this paper. The rapid transition from a wheel to a leg endows the robot with wheel-to-leap behavior. The general motion planning strategy of the leg-wheel, as well as the wheel-to-leap behavior, are explained in the demonstration example. The results confirm that the module can perform wheel-to-leap behavior with a height of up to 4.6 times the wheel radius. [ABSTRACT FROM AUTHOR]