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The behaviour of unpaced production lines with unequal means processing times, viriability, or buffer capacities
No full textIn this paper we study the operating behaviour and performance of reliable, unpaced and unbalanced serial production lines with either imbalanced service time means, unequal coefficients of variation, or uneven buffer capacities. The lines were simulated with various values of line length, buffer storage size, degree of imbalance, coefficient of variation, along with a number of imbalance configurations. The primary measures of efficiency were idle time and average buffer level. Output data from the discrete event simulation of such lines under their steady-state mode of operation were analyzed using a set of statistical methods. Various relationships between the independent and response variables, rankings of configurations and comparisons with balanced lines were obtained. For the mean processing times imbalance, it turned out that a bowl-shaped arrangement provides smaller idle time amounts and lower average buffer levels than those of a balanced line counterpart. As regards the variability imbalance, it was found that the best configurations are respectively, a bowl allocation and a monotone decreasing order, with the first resulting in decreased idle times and the second leading to lower average buffer levels than those of a balanced line. As far as the buffer size imbalance is concerned, it was concluded that the most advantageous patterns that generate lower idle times and average buffer levels as compared to a balanced line are to respectively distribute total available buffer capacity as evenly as possible along the buffers and to allocate more buffer capacity towards the end of the line
Unpaced serial production lines with two simultaneous sources of imbalance - Their operating characteristics
No full textThis paper investigates the behaviour of unpaced serial production lines with two concurrent imbalance sources, namely, lines that are simultaneously unbalanced with respect to either their work time means (MTs) and variability - as depicted by the coefficients of variation of processing times (CVs), their MTs and buffer capacities (BCs), or their CVs and BCs. The lines were simulated under stable operating conditions with different values of line length, buffer capacity, coefficient of variation, degree of imbalance, as well as a variety of imbalance patterns. Making use of a number of statistical methods, idle time and average buffer level output data were analysed and compared to a balanced line counterpart. Conclusions concerning the relationships among the exogenous and endogenous variables were made. For the MT and CV imbalance, the configuration providing the lowest idle time turned out to be an inverted bowl pattern for MT, along with a bowl-shaped arrangement for CV, whereas the best configuration that generally generates low average buffer levels was found to be an MT decreasing order, together with a CV bowl allocation. As for unbalanced MTs and BCs, it was found that in terms of idle time the best unbalanced pattern is an MT bowl configuration, coupled with a distribution of buffer capacity as evenly as possible. On the other hand, for average buffer level the best pattern was a monotone decreasing MT order, together with an ascending buffer size order. As regards CV and BC imbalance, the most superior pattern with respect to idle time was identified as a bowl-shaped CV configuration, combined with a buffer placement whereby more buffer capacity is concentrated at the beginning of the line, but for average buffer level the most favourable pattern was a bowl-shaped CV assignment, together with a buffer arrangement under which the buffers are concentrated towards the end of the line
The impact of stock spams on volatility
No full textInternational audienceThis article is dedicated to study the impact of stock spams through the analysis of the variations of volatility. Our sample contains 110 firms quoted on emerging market, namely the penny stock market. The results, based on event study methodology and Generalized Autoregressive Conditional Heteroscedastic (GARCH) modelling, show positive and significant changes in volatility; a widening of the variation (lowest price–highest price) was noticed following the consignment of messages by the spammers. The sending of stock spams affected the behaviour of investors, thus indicating that the spamming activity is a lucrative business
Potentials of knowledge management 2.0 and implications for corporate governance
No full textInternational audienceThis paper explores the corporate adoption of Web 2.0 technologies to enhance knowledge flows within and across firms. It first investigates the nature of the Web 2.0 phenomenon. As social mechanisms determine the use of technologies in corporate environments, a literature review is carried out to understand how governance models influence the use of Web 2.0 tools for knowledge sharing. The paper concludes that employees have to be empowered along the implementation of Web 2.0-based information systems. The potential of Web 2.0 technologies to foster collaboration depends on the creation of liberal work cultures and corporate governance structures which firms establish. Managers have to take these governance-related conditions into account when they aim to foster the use of collaborative Web 2.0 technologies for knowledge sharing in corporate networks
Intrinsic motivations, self-esteem, and luxury goods consumption
No full textInternational audienceDespite the dramatic growth of the luxury market over the past two decades, luxury consumer research remains fragmentary and scant. To address this knowledge gap, this study investigates consumers' intrinsic motivations for purchasing luxury goods. Data were collected from 587 consumers and analyzed using structural equation modeling. The results show that consumers who are primarily intrinsically motivated tend to purchase luxury products for superior quality and self-directed pleasure. The findings also demonstrate that self-esteem, an important concept in psychology and consumer behavior but rarely studied in luxury research, relates strongly to self-directed pleasure
Uncovering the relationships between aspirations and luxury brand preference
No full textInternational audiencePurpose This paper seeks to test the effects of intrinsic and extrinsic aspirations on luxury brand preference. The objective is to help luxury marketers better understand and anticipate the psychological needs of their customers. Design/methodology/approach Based on a thorough review of the literature, a series of hypotheses are derived and tested using confirmatory factor analysis and structural equation modeling. The final sample consists of a total of 615 participants. Findings The main findings show that aspirations can affect luxury brand preference depending on the type of aspirations: positive for extrinsic aspirations and negative for intrinsic ones. The findings also suggest that intrinsic aspirations play a more substantial role in luxury consumer behavior than had been previously thought. Practical implications The findings suggest that luxury marketers should take into consideration the duality of intrinsic and extrinsic aspirations when designing marketing campaigns. Particularly, focusing advertising campaigns on extrinsic values seems restrictive and discards consumers who are intrinsically motivated. Originality/value Aspirations are important in social psychology research because they have a strong influence on individuals' behavior. However, little research has been done in marketing to assess the potential effects of aspirations on consumer behavior, especially within the context of luxury goods
The effects of joint operations time means and variability unbalance on production line performance
No full textInternational audienceIn this paper unpaced, unbalanced lines with respect to both their mean operation times (MTs) and Coefficients of Variation (CVs) were simulated with different lengths, buffer capacities, degrees of imbalance, and patterns of imbalance. Idle Time (IT), throughput and Average Buffer Level (ABL) data were generated and analysed. The best unbalanced configurations in terms of IT/throughput and ABL were respectively found to be an MT inverted bowl combined with a bowl shaped CV pattern, and an MT decreasing order combined with a bowl CV arrangement. The best patterns provided generally superior performance to that of a balanced line counterpart
Gender and family background as predictors of entrepreneurial drive in France
No full textcahier de recherche n°2009-11 E4This study analyses the role played by gender and personal environment in the definition ans establishment of professional values and vision of entrepreneurship amongst Higher Education students in Franc
Testing U.S. Advertising Belief and Attitude Measures in France
No full textInternational audienceThis article aims at testing the cross-national equivalence of advertising belief and attitude measures from the Unites States and France and an initial cross-national comparison of beliefs and attitudes toward advertising in general between samples from the United States and France. A field study among 100 U.S. and 98 French respondents was conducted using established measures of advertising belief and attitude measures. The research at hand found that U.S. respondents exhibited significantly more favorable beliefs toward the economic and social effects of advertising as well as significantly more favorable attitudes toward the institution of advertising and the instrument of advertising in general. The findings suggest that existing advertising belief and attitude measures are equally applicable and yield similar structures in the United States and France. However, the results of structural equation modeling suggest that cross-cultural advertising belief and attitudes might be better measured using either a two-factor or three-factor measure rather than the one-factor approach proposed in the literature
Improving the efficiency of unpaced production lines by unbalancing service time means
No full textInternational audienceThis paper investigates the benefits of deliberately unbalancing operation time means for non-automated production lines. The lines were simulated under the steady state condition, with various line lengths, buffer storage sizes, degrees of imbalance and patterns of imbalance. Output data were analysed using a set of statistical methods resulting in various conclusions being made. It was found that the best configurations are a bowl arrangement and a monotone decreasing order, with the first resulting in lower idle times and the second leading to lower average buffer levels than those of a balanced line