Comptabilité de gestion | EPFL Graph Search

La comptabilité de gestion, ou la comptabilité analytique, est un système d'information comptable (exprimé en unités monétaires) qui permet d'informer les dirigeants (ou managers) des organisations afin de prendre des décisions de gestion. Comptabilité de gestion et comptabilité analytique L'expression « comptabilité de gestion » a remplacé progressivement l'expression comptabilité analytique en France dans les années 1980. Mais les deux expressions sont parfaitement synonymes. L'expression comptabilité analytique faisait référence à la terminologie du plan comptable général (PCG) qui, en France jusqu'en 1999, réservait de long développements aux calculs de coûts, illustrés par des exemples. Cette partie ayant disparu du PCG depuis 1999, le vocabulaire comptable s'est largement inspiré de sources internationales depuis. L'expression "comptabilité de gestion" fait référence, dès les années 1980, à la traduction en français de l'expression anglaise "management accountin

Imprecise Security: Quality and Complexity Tradeoffs for Hardware Information Flow Tracking

Andrew James Becker, Wei Hu, Paolo Ienne, Ryan Charles Kastner

Secure hardware design is a challenging task that goes far beyond ensuring functional correctness. Important design properties such as non-interference cannot be verified on functional circuit models due to the lack of essential information (e.g., sensitivity level) for reasoning about security. Hardware information flow tracking (IFT) techniques associate data objects in the hardware design with sensitivity labels for modeling security-related behaviors. They allow the designer to test and verify security properties related to confidentiality, integrity, and logical side channels. However, precisely accounting for each bit of information flow at the hardware level can be expensive. In this work, we focus on the precision of the IFT logic. The key idea is to selectively introduce only one sided errors ( false positives); these provide a conservative and safe information flow response while reducing the complexity of the security logic. We investigate the effect of logic synthesis on the quality and complexity of hardware IFT and reveal how different logic synthesis optimizations affect the amount of false positives and design overheads of IFT logic. We propose novel techniques to further simplify the IFT logic while adding no, or only a minimum number of, false positives. Additionally, we provide a solution to quantitatively introduce false positives in order to accelerate information flow security verification. Experimental results using IWLS benchmarks show that our method can reduce complexity of GLIFT by 14.47% while adding 0.20% of false positives on average. By quantitatively introducing false positives, we can achieve up to a 55.72% speedup in verification time.

Assoc Computing Machinery2016

Operational Decisions and Supply Chain Dynamics

Olov Isaksson

While traditional research in operations management has focused on mathematical models for improving the flow of physical goods and information, this dissertation takes a quantitative empirical approach. With three distinct research projects it revisits central topics in the field and explores how operational decisions affect the performance of the firm and its trading partners. Chapter 2 examines the financial consequences that inventory leanness has on firm performance. We conduct an econometric analysis using 4,324 publicly traded U.S. manufacturing companies for the period 1980-2008. Using an instrumental variable fixed effects estimator we find a nonlinear relationship between inventory leanness and financial performance. However, we note that the maximum point of this inverted U-shaped relationship often lies at the extreme end of the investigated sample—suggesting a decreasing return from leanness rather than an optimal level. We show that the strength of this relationship is highly dependent on both industry and inventory type (raw materials, work in process and finished goods). The main novelty and direct implication of our findings is that most firms still have much potential to increase profitability by becoming leaner and they are unlikely to cross a threshold where profitability decreases with increased leanness. We display how much the average firm could gain by becoming leaner and show how this sensitivity changes by inventory component and industry. Finally, we highlight several new econometric aspects that we believe must be addressed when empirically investigating the inventory-performance link. The bullwhip effect is said to occur when demand variability is amplified from a downstream site (buyer) to an upstream site (supplier) in the supply chain. Chapter 3 contributes to the literature that empirically investigates the bullwhip effect by providing new evidence regarding its prevalence and magnitude. In contrast to previous work, we use a two-echelon approach, which allows us to observe varia- tions at both the upstream and the downstream sites. By drawing on a financial accounting standard regarding information disclosure about major customers, we are able to link 5,494 buyers-supplier dyads between 1976 and 2009. We merge this information with quarterly financial accounting data to form a sample of 14,933 buyer-supplier dyad observations. We correct for sample selection bias using propensity score matching and estimate the average bullwhip effect in our sample to 1.90 (i.e. 90% demand variability amplification between echelons). A significant bullwhip effect is found across industries (mining, manufacturing, wholesale and retail) and is supported by several robustness checks. We investigate and discuss how these results can be generalized beyond our sample. Chapter 4 explores knowledge spillovers in the supply chain. By building on the organizational learning literature we discuss how knowledge is diffused in the supply chain. Buyers-supplier relationship data is merged with financial accounting data, patent data and publication data to create a sample of 974 buyer-supplier dyad observations in the high tech industries. Using fixed effects estimation we show that a 1% increase in patent intensity at the buyers, on average leads to a 1% increase in patent intensity at the supplier. We find that the duration of the buyer-supplier relationship positively moderates this effect, but that the supplier’s sales dependency on the buyer has a negative moderating role. The technological proximity of the two firms, however, is not found to have a significant effect on spillovers. We discuss the implications of our findings for individual firms and theory.

EPFL2013

Modeling and mitigating supply chain disruptions as a bilevel network flow problem

René Yves Glogg, Anna Timonina-Farkas

Years of globalization, outsourcing and cost cutting have increased supply chain vulnerability calling for more effective risk mitigation strategies. In our research, we analyze supply chain disruptions in a production setting. Using a bilevel optimization framework, we minimize the total production cost for a manufacturer interested in finding optimal disruption mitigation strategies. The problem constitutes a convex network flow program under a chance constraint bounding the manufacturer's regrets in disrupted scenarios. Thus, in contrast to standard bilevel optimization schemes with two decision-makers, a leader and a follower, our model searches for the optimal production plan of a manufacturer in view of a reduction in the sequence of his own scenario-specific regrets. Defined as the difference in costs of a reactive plan, which considers the disruption as unknown until it occurs, and a benchmark anticipative plan, which predicts the disruption in the beginning of the planning horizon, the regrets allow measurement of the impact of scenario-specific production strategies on the manufacturer's total cost. For an efficient solution of the problem, we employ generalized Benders decomposition and develop customized feasibility cuts. In the managerial section, we discuss the implications for the risk-adjusted production and observe that the regrets of long disruptions are reduced in our mitigation strategy at the cost of shorter disruptions, whose regrets typically stay far below the risk threshold. This allows a decrease of the production cost under rare but high-impact disruption scenarios.

SPRINGER HEIDELBERG2022

Operational Decisions and Supply Chain Dynamics

Olov Isaksson

EPFL2013