922 research outputs found
Failure detection and identification for a reconfigurable flight control system
Failure detection and identification logic for a fault-tolerant longitudinal control system were investigated. Aircraft dynamics were based upon the cruise condition for a hypothetical transonic business jet transport configuration. The fault-tolerant control system consists of conventional control and estimation plus a new outer loop containing failure detection, identification, and reconfiguration (FDIR) logic. It is assumed that the additional logic has access to all measurements, as well as to the outputs of the control and estimation logic. The pilot may also command the FDIR logic to perform special tests
Conflicting claims and equilibrium adjustment processes in a stock-flow consistent macro model
We revisit the old but still vibrant Post-Keynesian debate over "fully-adjusted positions", defined by the long-run equality of actual and standard utilisation rates. The central proposition of this paper is that in a world where different groups inside and outside firms have different objectives, the equality of actual and standard utilisation should not be treated as the (only possible) long-run equilibrium condition. The argument is illustrated in a model of target return pricing with conflict inflation, building on Lavoie (2002, 2003). A "common language" for the conflicting claims by shareholders, managers, workers and banks is developed in terms of target profit rates, and it is shown that these contradictory claims can be partly reconciled through variations in the utilisation rate. The analysis unifies history and equilibrium in the sense that the nature of and the adjustment to the final equilibrium position depends on the objectives of the dominant social groups. We distinguish a "Fordist regime" and a "financialisation regime" and produce simulation results within a simple stock-flow consistent model that are broadly consistent with the stylised facts of these distinct historical phases of capitalism.Macroeconomic policies, New Consensus Model, Post-Keynesian Model, inflation targeting
Attitudes of Clinical Psychologists Towards the Reporting of Nonhuman Animal Abuse
Research consistently demonstrates that nonhuman animals are capable of cognition and complex emotions, but their legal status in the United States remains similar to that of property. As such, they are not protected under laws mandating psychologists to report suspicions of abuse of populations that are judged to be vulnerable and unable to protect themselves, such as children, the elderly and people with disabilities (American Psychological Association [APA], 2010). Findings from previous research suggest that animal abuse is a relatively common topic encountered in therapy and the majority of clinicians are in favor of allowing voluntary reporting of nonhuman animal abuse (Nelson, 2002; Schaefer, Hays, & Steiner, 2007). However, few psychologists report inquiring about animal abuse and neglect, with lack of education about animals’ welfare and human-animal violence posed as a primary reason for this phenomenon. To fill this gap in the literature, 133 psychologists were surveyed regarding how they viewed animal abuse/neglect, whether they encounter it in professional practice, and how willing they are to report to animal protection agencies or law enforcement. Then, following a brief intervention, participating psychologists revealed their post-intervention willingness to inquire about animals in their clients’ lives and their willingness to report animal abuse/neglect to animal protection agencies or law enforcement, as well as the reason that they agreed or disagreed with reporting animal abuse. Results demonstrated that animal abuse and neglect is commonly encountered by participating psychologists although few inquire about it during intake interviews. Further, the brief intervention significantly increased both disposition towards inquiring about animals in their clients’ lives and willingness to report animal abuse/neglect to animal protection or law enforcement agencies. These findings have important implications for informing APA guidelines towards including voluntary or mandatory reporting of animal abuse and neglect
Priority allocation decisions in large scale MTO/MTS multi-product manufacturing systems : Technical report
In this paper, the authors consider a single stage multi-product manufacturing facility producing a large number of end-products for delivery within a service constraint for the customer lead-time. The manufacturing facility is modeled as a multi-product, multi-priority queuing system. In order to reduce inventory costs, an e±cient priority allocation between items consists in producing some items according to a Make-To-Stock (MTS) policy and others according to a Make-To-Order (MTO)policy epending on their features (costs, required lead-time, demand rates). The authors propose a general optimization procedure that gives a near-optimal °ow control (MTO or MTS) to associate with each product and the corresponding near-optimal priority strategy. We illustrate e±ciency of our procedure via several examples and by a numerical analysis. In addition, we show numerically that a small number of priority classes is su±cient to obtain near-optimal performances.Make-to-Stock (MTS); Make-to-Order (MTO); Priority allocation; Scheduling rule; Heterogeneous multi-product queuing system
Teaching the effect of COVID-19 with a manageable model
This note has one main ambition. It seeks to provide a very simple macroeconomic framework to explain the economic impact of the COVID-19 pandemic. The explanation for the unprecedented magnitude of the recession over a short span of time is to be found in the peculiar form of the shock due to the various lockdowns involving two recessive shocks simultaneously. Besides, this model is original in that although it is driven by demand it is capable of dealing with supply issues without entailing any additional technical difficulties
L'entreprise est à nous…
International audienceQuand on se demande si « l’entreprise est à nous », encore faut-il définir quel groupe se cache derrière le « nous »… Ce même slogan peut en effet être scandé par des travailleurs ou des actionnaires. Derrière cette lutte relative à la revendication d’un droit de propriété sur l’entreprise, on retrouverait le conflit entre le travail et le capital. Or, force est de constater que, ces dernières décennies, c’est le point de vue actionnarial qui domine celui des travailleurs (Favereau, 2014)
Le Nord-Pas-de-Calais, entre mutations éconmiques et développement humain
La région Nord-Pas-de-Calais connaît depuis plusieurs décennies une transformation de son tissu productif qui pose la question de l’arbitrage entre mutation économique et progrès social: là où les difficultés économiques ont été les plus marquées, des territoires ont pu connaître un réel décrochage, avec de moindres perspectives de progrès social. Cette problématique est accentuée depuis 2008, avec une crise qui a des conséquences importantes sur les territoires
Service capacity pooling in M/G/1 service systems
International audienceWe study the cost-sharing problem among independent service providers in a service capacity pooling system. The effective improvement of such pooling system can be achieved by reducing the resource idleness in case of congestion. In this paper, we model both the service provider and the cooperative coalition as a single server queue. We attempt to answer the following questions: (i) which coalition strategy should be used; and (ii) which allocation rule should be selected in order to maintain the stability of the coalition? In particular, we consider the service pooling with a fixed service capacity for M/G/1 service systems. The benefit of the pooling system is due to the shortened waiting queue in the overall system. We develop the corresponding cooperative game with transferable utility, and analyze the core allocations. Although it is difficult to express a core allocation explicitly for the game, we prove the non-emptiness of the core. We give a reasonable expression of Equal Profit Method to distribute the cost for our game, and investigate a number of cost allocation rules under three typical situations to evaluate the gain of the service pooling strategy for each service provider. The numerical results show that the cost allocation rule proposed gives a reasonable cost-sharing result considering the contribution of each participant
Adjust or invest : what is the best option to green a supply chain?
Greening a supply chain can be achieved by considering several options. However, companies lack of clear guidelines to assess and compare these options. In this paper, we propose to use multiobjective optimization to assess operational adjustment and technology investment options in terms of cost and carbon emissions. Our study is based on a multiobjective formulation of the economic order quantity model called the sustainable order quantity model. The results show that both options may be effective to lower the impacts of logistics operations. We also provide analytical conditions under which an option outperforms the other one for two classical decision rules, i.e. the carbon cap and the carbon tax cases. The results allow deriving some interesting and potentially impacting practical insight
Suivi des prairies par mesures hyperspectrales et séries temporelles d’images satellitaires à haute résolution spatiale : influence des modes de gestion sur le signal spectral
Une prairie est un milieu ouvert caractérisé par une végétation majoritairement herbacée pouvant présenter une importante biodiversité. Les modes de gestion déséquilibrent ce milieu physiquement, mais leurs impacts sur la réflectance ne sont pas connus. Ainsi, des mesures hyperspectrales ont permis de suivre l’évolution de la réflectance, mais aussi d’identifier le potentiel de la mission Sentinel-2 pour ce suivi. Dans le cas où aucune gestion n’est appliquée, les prairies deviennent sénescentes jusqu’à la fin de la saison de végétation. La sénescence augmente la réflectance dans le rouge et la diminue dans le proche infrarouge. Les opérations de gestion impactent principalement ces longueurs d’onde. Cet impact s’observe instantanément après la fauche. L’hétérogénéité spectrale des prairies est plus importante après une opération de gestion, particulièrement après une fauche. Les prairies sont alors composées de végétation sénescente, saine et de sol nu. L’impact du pâturage sur la réflectance est plus important par rapport à la fauche. De plus, ces opérations ont pour effet de relancer la croissance de la végétation en diminuant la compétitivité entre la végétation sénescente et sous-jacente. Un suivi hypertemporel est primordial pour identifier ces opérations à partir de la réflectance
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