It is increasingly common for computer users to have access to several computers on a network, and hence t o b e able to execute many of their tasks on any of several computers. The choice o f w h i c h c omputers execute which tasks is commonly determined b y users based o n a k n o w l e dge of computer speeds for each task and the current load on each computer. A number of task scheduling systems have been developed that balance the load of the computers on the network, but such systems tend to minimize the idle time of the computers rather than minimize the idle time of the users. This paper foc u s e s o n t h e b ene ts that can be achieved when the scheduling system considers both the computer availabilities and the performance o f each task on each computer. The SmartNet resource scheduling system is described and compared t o t w o di erent resource a l l o cation strategies: load balancing and user directed assignment. Results are p r esented where t h e o p eration of hundreds of di erent networks of computers running thousands of di erent mixes of tasks are simulated i n a b atch environment. These results indicate that, for the computer environments

We tested the proposition that maternal body mass affects litter production and recruitment in the cotton rat (Sigmodon hispidus) in Kansas. We also addressed hypotheses about why cotton rats in Kansas are larger and more fecund than conspecifics in Texas. We livetrapped cotton rats on both control and food-supplemented grids. Pregnant females were briefly confined until parturition; their pups were weighed and toe-clipped, then mother and young were returned to the site of capture. Subsequent trapping revealed survival of the offspring, i.e., ability of mothers to recruit pups into the population. Heavier mothers on both sets of grids gave birth to larger, heavier litters and had more pups survive to recruitment. The percentage of pups surviving was not related to maternal mass or to pup mass, so the increased recruitment resulted primarily from heavier mothers' having more rather than heavier pups. Mothers on the supplemented grids bore larger and heavier litters than their same-mass counterparts on the control grids. Despite their larger litters, lighter (ca. 100 g) mothers on the supplemented grids recruited fewer pups than their same-mass counterparts on control grids. Because heavier female cotton rats are more fecund, our results are consistent with the hypothesis that cotton rats in Kansas are larger than in those in Texas because of selection for increased litter size in Kansas. Seasonality in Kansas restricts the number of breeding opportunities and provides a nutrient pulse that supports rapid reproduction in the growing season.RCsumC : Nous avons CprouvC l'hypothkse selon laquelle la masse de la mkre affecte la reproduction et le recrutement chez le Rat-cotonnier hirsute (Sigmodon hispidus) au Kansas. Nous avons Cgalement examine les hypothkses qui tentent d'expliquer pourquoi les rats-cotonniers de cette espkce au Kansas sont plus gros et plus fCconds que ceux du Texas. Nous avons install6 des pikges dans des grilles-Cchantillons tCmoins et des grilles-Cchantillons additionnkes de nourriture. Les femelles enceintes ont Ct C gardCes en captivitC pendant une courte pCriode jusqu'a la parturition; leurs petits ont Ct C pesCs et amputCs d'un orteil; mkres et petits ont ensuite Ct C retournks au site de capture. Les piCgeages subsCquents ont permis de verifier si les petits avaient survCcu et si la mkre avait rCussi a les intCgrer dans la population. Dans les deux sCries de grilles-Cchantillons, les mkres les plus lourdes ont donnC naissance a des portCes plus grosses et plus lourdes et leurs petits Ctaient plus aptes a survivre jusqu'a leur intigration dans la population. Le pourcentage de petits qui ont survCcu n'ktait pas reliC a leur masse, ni a la masse de leur mkre, et le recrutement accru Ctait donc reliC au fait que les mkres plus lourdes produisaient un plus grand nombre de petits plut6t que des petits plus lourds. Les mkres des grilles-Cchantillons a supplCment de nourriture ont eu des portCes plus grosses et plus lourdes que les mkres de masse Cgale des grilles tkmoins. En dCpit du nombre plus ...

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