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The focus of this paper is to present a control methodology for the regulation of loading and processing of parts in a manufacturing cell in the presence of minor disturbances. The control methodology addresses three states in the planning horizon of a manufacturing cell: steady state, transient state, and a match-up state when the system is transitioning from transient to steady state operation. The part loading regulation of the cell is accomplished via optimization of appropriate cost functions associated with each state. The proposed control architecture for the cell part regulator utilizes these cost functions to enforce the desired regulatory properties. Theoretical developments and detailed examples can be found in Saleh et al., 1990; Saleh, 1988.

Humans are now recognized as the main drivers of environmental change, leaving the future ofour planet dependent on human action or inaction. Although the outlook of our planet is often depicted in a 'doom and gloom' manner due to recent troubling environmental trends, we suggest that a 'good Anthropocene' (in which human quality of life may be maintained or improved without cost to the environment) is attainable if we engage in adaptive, multi-disciplinary actions capable of addressing the socio-ecological issues of today and tomorrow. Early-career conservation scientists and practitioners have an unmatched understanding of novel technologies and social connectivity and, as those left with the ever-growing responsibility to be the problem solvers of the attributed increasing environmental consequences of living in the Anthropocene, their perspectives on steps towards a good Anthropocene are valuable. Here we present a list of 20 actions derived by early-career conservation scientists and practitioners for conservationists to help achieve a good Anthropocene that utilize the social connectivity and technology of today. Central to these actions are the notions that multi-, inter-, and trans-disciplinary collaboratives that embrace diverse world views need to be integrated into decision-making processes; training and outreach platforms need to communicate both environmental challenges and solutions broadly; and conservation successes need to be acknowledged and disseminated in a forward-looking, adaptive capacity. Together the 20 actions identified here reinforce the underlying paradigm shift that must accompany living in the Anthropocene, given that biodiversity and healthy ecosystems are requisite for sustained human life. By sharing this list of actions, we look to promote positive socio-environmental changes towards the collective goal of achieving a good Anthropocene. Key words: Anthropocene, positive futures, early-career researchers. On reconnait maintenant que les etres humains sont les principaux responsables des changements environnementaux, laissant l'avenir de notre planete dependant de l'action ou de l'inaction humaine. Meme si les perspectives de notre planete sont souvent depeintes de maniere pessimiste a cause des recentes tendances environnementales inquietantes, les auteurs suggerent qu'un <> (dans lequel la qualite de vie des humains peut etre maintenue ou amelioree sans cout environnemental) est atteignable si nous nous engageons dans des actions adaptatives multidisciplinaires capables de s'attaquer aux problemes socioecologiques d'aujourd'hui et de demain. Les scientifiques et les praticiens de la conservation en debut de carriere ont une comprehension sans precedent des nouvelles technologies et de la connectivite sociale et, en tant que personnes a qui l'on confie la responsabilite de plus en plus lourde d'agir comme solutionneurs de problemes en ce qui a trait aux consequences environnementales croissantes que l'on attribue a vivre dans l'Anthropocene, leurs perspectives sur les etapes conduisant a un bon Anthropocene sont precieuses. Les auteurs presentent ici une liste de 20 actions proposees par des scientifiques et des praticiens de la conservation en debut de carriere a l'intention des agents de protection de l'environnement pour les aider a atteindre un bon Anthropocene par l'utilisation de la connectivite sociale et de la technologie d'aujourd'hui. Au coeur de ces actions se trouvent des notions : de collaborations multi-, inter- et transdisciplinaires qui epousent diverses conceptions du monde qui doivent etre integrees aux processusde prisede decision;de plateformes de formation et dediffusion necessaires pour communiquer largement les defis et les solutions en matiere d'environnement; et de succes en matiere de conservation qui doivent etre reconnus et dissemines dans la perspective d'une capacite d'adaptation tournee vers l'avenir. L'ensemble des 20 actions identifiees ici renforcent le changement de paradigme sous-jacent qui doit accompagner la vie dans l'Anthropocene, puisque la biodiversite et des ecosystemes en sante sont necessaires au developpement humain durable. En partageant cette liste d'actions, les auteurs desirent promouvoir des changements socio-environnementaux positifs vers l'objectif collectif d'atteindre un bon Anthropocene. [Traduit par la Redaction] Mots-cles : Anthropocene, avenir prometteur, chercheurs en debut de carriere., Introduction Human actions have led planet Earth into the Anthropocene epoch (Crutzen and Stoermer 2000). Humans are now recognized as a predominant agent of ecosystem change on the planet, exemplified [...]

Predation is a leading cause of nest failure in birds, which has significant consequences on their population dynamics. Rodents commonly prey on nests in deciduous forest habitats. This has important implications considering how rodent populations fluctuate with changes in resource availability, such as synchronized but intermittent tree-seed production (mast). In this study, we investigated ground-nest egg predation by rodents over 2 years characterized by high and low beech (Fagus grandifolia Ehrh.) seed availability (mast vs. no-mast years). We used artificial nests monitored by motion-sensing cameras on a study site where eastern chipmunk (Tamias striatus (Linnaeus, 1758)) local abundance was known. We placed the artificial nests in areas of high and low chipmunk abundance as proxy of predation risk. Blue Jays (Cyanocitta cristata (Linnaeus, 1758)) depredated the most eggs overall, but rodent population and egg depredation increased in 2018 following the 2017 mast. However, chipmunks were minor predators and their local abundance did not reflect predation risk. Our results highlight the complexity of predation dynamics on ground-nesting birds and the importance of studying them locally and over multiple years. Key words: eastern chipmunk, Tamias striatus, masts, rodent foraging, predation risk, corvids. La predation est une des principales causes d'echec des nids chez les oiseaux et elle a d'importantes repercussions sur la dynamique de leurs populations. La predation de nids par les rongeurs est frequente dans les habitats de foret de feuillus. Cela est important au vu des fluctuations des populations de rongeurs au fil des variations de la disponibilite de ressources, comme la production de graines d'arbres synchronisee, mais intermittente (fructification massive). Nous avons etudie la predation d'oeufs de nids au sol par des rongeurs pendant 2 annees caracterisees, respectivement, par des disponibilites forte et faible (annees de fructification massive et non massive) de graines de hetre agrandes feuilles (Fagus grandifolia Ehrh.). Nous avons utilise des nids artificiels surveilles a l'aide de cameras a detection de mouvement dans un site d'etude ou l'abondance locale des tamias rayes (Tamias striatus (Linnaeus, 1758)) etait connue. Nous avons place des nids artificiels dans des secteurs de forte et de faible abondance de tamias rayes, utilisee comme variable substitutive du risque de predation. La plus importante predation d'cufs, globalement, etait la predation par les geais bleus (Cyanocitta cristata (Linnaeus, 1758)), mais la population de rongeurs et la predation d'c[epsilon]ufs ont augmente en 2018 suivant l'annee de fructification massive de 2017. Les tamias rayes etaient toutefois des predateurs mineurs, et leur abondance locale ne refletait pas le risque de predation. Nos resultats soulignent la complexite de la dynamique de predation des oiseaux nichant au sol et l'importance de les etudier a l'echelle locale et sur plusieurs annees. [Traduit par la Redaction] Mots-cles: tamia raye, Tamias striatus, fructifications massives, approvisionnement des rongeurs, risque de predation, corvides., Introduction Understanding population dynamics is a fundamental aspect of ecology because it relates to how species are adapted to their environment and their capacity to persist through time. In passerine [...]

From an engineering application point of view in reducing fugitive particulate mailer emissions, this paper presents experimental data comparing the efficiency of woven straw at reducing entrained emissions of particulate matter with diameters less than 10 µm ([PM.sub.10]) with that for particulate matter with diameters less than 2.5 µm ([PM.sub.2.5]) at construction sites. A series of field-analogous experiments were carried out to continuously measure [PM.sub.10] and [PM.sub.2.5] using laser particle monitors in an artificial wind tunnel system. It was found that the efficiency of woven straw at reducing either [PM.sub.10] or [PM.sub.2.5] is significantly dependent on the woven straw coverage ratio. The maximum reduction efficiencies for [PM.sub.10] and [PM.sub.2.5] are about 40% and 12%, respectively. Note that the reduction efficiencies approach zero as the coverage ratio is less than about 40%. Total elimination of PM3.5 and [PM.sub.10] emissions is not possible, even using full-coverage woven straw. Reduction of [PM.sub.2.5] emissions is less efficient than that of [PM.sub.10] emissions using woven straw, and this trend is likely more obvious with an increase in the woven straw coverage ratio. The ratio of reduction efficiencies (R) between [PM.sub.2.5] and [PM.sub.10] for woven straw decreased slightly with an increase in the woven straw coverage ratio. Overall, for wind speeds of 0.5-3.0 m/s, sill contents of 4.8%-21,0%, and soil moisture contents of I0%-30% as used in this work, the average value of R is 0.31. The effects of wind velocity, silt content, and moisture content on the reduction efficiencies are also discussed. Key words: fugitive dust, reduction efficiency, [PM.sub.10], [PM.sub.2.5], woven straw, air quality. D'un point de vue d'application technique pour reduire les emissions fugitives de matieres particulaires, cet article presente des donnees ex peri mental es pour comparer l'efficacite en reduction de la paille tissee pour les emissions de matieres particulaires entre [PM.sub.10] et [PM.sub.2.5] de zones exposees. Dans cette etude, des d'experiences analogues sur le terrain ont ete realisees pour mesurer en continu les [PM.sub.10] et [PM.sub.2.5] au moyen de detecteurs de particules au laser dans un tunnel aerodynamique artificiel. L'efficacite de la reduction de la paille tressee a reduire soit [PM.sub.10] ou [PM.sub.2.5] depend beaucoup du rapport de couverlure de la paille tressee. Les efficacites maximales de reduction pour [PM.sub.10] et [PM.sub.2.5] sont respectivement d'environ 40% el 12%. Il faul remarquer que les efficacites de reduction atteignent pres de zero lorsque le rapport de couverlure est inferieur a environ 40 %. Un autre point interessant est que l'elimination lotale des emissions pm1.5 et [PM.sub.10] est impossible meme en utilisant une couverlure complete de paille tressee. La reduction des emissions [PM.sub.2.5] est moins efficace que celle des emissions [PM.sub.10] pour la paille tressee et cette tendance sera probablement plus evidente avec l'augmentation du rapport de couverlure en paille tressee. La presente etude montre que le rapport des efficacites de reduction (R) entre [PM.sub.2.5] et [PM.sub.10] par la paille tressee diminue un pen avec une augmentation du rapport de couverlure de paille tressee. Regie generate, sous des conditions utilisees dans ce travail, soit une vitesse de vent entre 0,5 et 3,0 m/s, un contenu en silt entre 4.8 et 21 % et une humidite entre 10 et 30%, la valeur R est de 0,31 en moyenne. Les effets de la vitesse de vent, du contenu en silt et de 1'humidite sur les efficacites de reduction sont egalement abordes dans cet article. Mots-cles : poussieres diffuses, efficacite de reduction, [PM.sub.10], [PM.sub.2.5], paille tressee. qualite de fair., Introduction The presence of excessive particles in the atmosphere is considered to be one of the major environmental problems in urban and densely populated areas (Furusjo et al. 2007). Considerable [...]

This article addresses a rental fleet sizing problem (RFS) in the context of the truck rental industry, subject to uncertain customer travel time and nonstationary customer demand that is dependent on geographical location, time, and the economic cycle of the industry. We integrate tactical (asset purchases and sales) and operational (empty truck movement and vehicle assignment) decisions, with the explicit incorporation of an asset age factor, to achieve lower cost solutions. Typically, the length of time horizon and number of locations under consideration are quite large, which makes the RFS model computationally challenging to solve. Aggregation procedures are employed for location clustering and end-of-horizon effects are examined through demand scenario-based analyses. For the reduced time-space networks, decision analyses are conducted for the RFS model to provide insights into the truck rental business regarding asset movement decisions and asset procurement/disposal decisions over time and locations., RENTAL FLEET SIZING PROBLEM Determining the number of vehicles to be maintained in a transportation system in order to meet demand at minimal cost is traditionally known as the fleet [...]

We evaluated the relative importance of intrinsic (density-dependent) and extrinsic (density-independent) sources of resource variability in the dynamics of bighorn sheep (Ovis canadensis Shaw, 1804) populations in southwestern USA. We tested the hypothesis that populations experiencing greater variation in forage availability are less likely to be at equilibrium density with forage supplies, and thus, would demonstrate weaker evidence of intraspecific competition. We used regression to relate population growth rate to rainfall (forage conditions) and to abundance (intraspecific competition) for 20 sheep populations, and we estimated the strength of the effects of density and rainfall for each population. Then we compared among populations to look for relationships between the strengths of rainfall and density effects and the variability in rainfall experienced by each population. Populations demonstrating a density effect were associated with environments having lower variability than those that did not. Populations showing a rainfall effect were associated with environments having a variability higher than those that lacked a rainfall effect. These findings are consistent with the hypothesis that populations experiencing higher variation in forage resources are less likely to achieve an equilibrium density with forage supplies where intraspecific competition would be a large determinant to the dynamics of that population. Nous avons evalue l importance relative des sources intrinseques (dependantes de la densite) et extrinseques (inde pendantes de la densite) de variabilite des ressources dans la dynamique de populations de mouflons du Canada (Ovis canadensis Shaw, 1804) dans le sud-ouest des E.-U. Nous testons l'hypothese qui veut que les populations qui connaissent une plus grande variabilite dans la disponibilite du fourrage sont moins susceptibles d'etablir une densite d'equilibre avec leurs ressources fourrageres et qu'ainsi elles presentent moins d'indications de competition intraspecifique. La regression nous a servi a relier le taux de croissance de la population aux precipitations (condition du fourrage) et a l'abondance (competition intraspecifique) chez 20 populations de mouflons; nous avons aussi estime la force des effets de densite et des precipitations pour chaque population. Nous avons ensuite compare les populations pour rechercher des relations entre la force des effets des precipitations et de la densite et la variabilite des precipitations eprouvee par chaque population. Les populations qui subissent un effet de densite sont plus souvent associees aux environnements qui ont une variabilite plus faible que celles qui ne connaissent pas d'effet de densite. Les populations qui eprouvent un effet des precipitations sont associees a des environnements qui possedent une variabilite plus elevee que ceux frequentes par les populations qui ne subissent pas l'effet des precipitations. Ces resultats s'accordent avec l'hypothese selon laquelle les populations qui eprouvent une variation plus importante de leurs ressources fourrageres sont moins susceptibles d'atteindre une densite d'equilibre avec leurs approvisionnements de fourrage, une situation dans laquelle la competition intraspecifique serait un facteur determinant majeur de leur dynamique de population. [Traduit par la Redaction], Introduction The influence of forage conditions on animal populations can originate from two sources: (1) intrinsic factors reflecting how animals affect their forage supplies through consumption and (2) extrinsic factors [...]

Advanced technologies like nuclear power and looming environmental threats such as global climate change present major policy challenge for modern cultures. Public policy about such crucial and complex issues depends on public attitudes, which, in turn, tend to be strongly affected by mass media coverage. How 'well' has the mass media portrayed these two evolving risk stories? Employing perspectives from both journalism and social science, this article will first review the history of mass media coverage of each topic, then analyze their differences., Advanced technologies like nuclear power and looming environmental threats such as global climate change present major policy challenges for modern cultures. Public policy about such crucial and complex issues depends [...]

Men of the African diaspora are diagnosed with--prostate cancer much later than Caucasians and the mortality rate is significantly higher in these groups than among Caucasians. This study investigates health beliefs surrounding prostate health in a sample of African American and Caribbean men and identifies reasons men have for delaying or avoiding prostate screenings. One hundred African American and Caribbean men recruited from three churches, aged 37-89, were surveyed about their health seeking behaviors and knowledge of prostate cancer. Forty-five of these men also attended a seminar on the importance of early detection. Eighty percent of the men revealed they were embarrassed to have digital rectal examinations. Sixty percent feared impotence and incontinence after treatment if diagnosed with cancer. Findings reveal that attention to cultural realities may assist healthcare professionals in planning culturally sensitive educational interventions in the community that may narrow the health disparities gap in this population. Key Words: Prostate Cancer, Screening, African American Men, Caribbean Men, Health Disparities., Prostate cancer, is the most frequently diagnosed cancer in the United States, accounting for 33% of all cancer ,re. cases among men (American Cancer Society, 2004), and is the second [...]

Abstract: Black men are suffering disproportionately from most illnesses. Action is needed to decrease the current health disparity. An important step in decreasing this disparity is to understand social factors [...]