915 resultados para Supplementary runs rules


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Various software packages for project management include a procedure for resource-constrained scheduling. In several packages, the user can influence this procedure by selecting a priority rule. However, the resource-allocation methods that are implemented in the procedures are proprietary information; therefore, the question of how the priority-rule selection impacts the performance of the procedures arises. We experimentally evaluate the resource-allocation methods of eight recent software packages using the 600 instances of the PSPLIB J120 test set. The results of our analysis indicate that applying the default rule tends to outperform a randomly selected rule, whereas applying two randomly selected rules tends to outperform the default rule. Applying a small set of more than two rules further improves the project durations considerably. However, a large number of rules must be applied to obtain the best possible project durations.

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OBJECTIVES To investigate the frequency of interim analyses, stopping rules, and data safety and monitoring boards (DSMBs) in protocols of randomized controlled trials (RCTs); to examine these features across different reasons for trial discontinuation; and to identify discrepancies in reporting between protocols and publications. STUDY DESIGN AND SETTING We used data from a cohort of RCT protocols approved between 2000 and 2003 by six research ethics committees in Switzerland, Germany, and Canada. RESULTS Of 894 RCT protocols, 289 prespecified interim analyses (32.3%), 153 stopping rules (17.1%), and 257 DSMBs (28.7%). Overall, 249 of 894 RCTs (27.9%) were prematurely discontinued; mostly due to reasons such as poor recruitment, administrative reasons, or unexpected harm. Forty-six of 249 RCTs (18.4%) were discontinued due to early benefit or futility; of those, 37 (80.4%) were stopped outside a formal interim analysis or stopping rule. Of 515 published RCTs, there were discrepancies between protocols and publications for interim analyses (21.1%), stopping rules (14.4%), and DSMBs (19.6%). CONCLUSION Two-thirds of RCT protocols did not consider interim analyses, stopping rules, or DSMBs. Most RCTs discontinued for early benefit or futility were stopped without a prespecified mechanism. When assessing trial manuscripts, journals should require access to the protocol.

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Der Beitrag diskutiert Möglichkeiten zur Automatisierung von Kundenbeziehungsprozessen im Customer Relationship Management mit Hilfe von Business Rules. Anhand einer CRM-Architektur werden Anwendungsmöglichkeiten erörtert und am Beispiel einer Cross-Selling-Kampagne vertieft. Technische Aspekte werden dabei nicht im Detail betrachtet. Der Schwerpunkt liegt vielmehr in der Diskussion von Automatisierungs- und Integrationspotenzialen durch den Einsatz von Business Rules, wie sie in zunehmend individualisierten Kundenbeziehungen in Massenmärkten gegeben sind.

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This paper develops a general theory of land inheritance rules. We distinguish between two classes of rules: those that allow a testator discretion in disposing of his land (like a best-qualified rule), and those that constrain his choice (like primogeniture). The primary benefit of the latter is to prevent rent seeking by heirs, but the cost is that testators cannot make use of information about the relative abilities of his heirs to manage the land. We also account for the impact of scale economies in land use. We conclude by offering some empirical tests of the model using a cross-cultural sample of societies.

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Economic models of negligence ordinarily involve a single standard of care that all injurers must meet to avoid liability. When injurers differ in their costs of care, however, this leads to distortions in their care choices. This paper derives the characteristics of a generalized negligence rule that induces injurers to self-select their optimal care levels. The principal features of the rule are (1) the due standard of care is maximal, and (2) liability increases gradually as injurers depart further from this standard. The results are broadly consistent with the gradation in liability under certain causation rules and under comparative negligence.

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This paper examines four equivalent methods of optimal monetary policymaking, committing to the social loss function, using discretion with the central bank long-run and short-run loss functions, and following monetary policy rules. All lead to optimal economic performance. The same performance emerges from these different policymaking methods because the central bank actually follows the same (similar) policy rules. These objectives (the social loss function, the central bank long-run and short-run loss functions) and monetary policy rules imply a complete regime for optimal policy making. The central bank long-run and short-run loss functions that produce the optimal policy with discretion differ from the social loss function. Moreover, the optimal policy rule emerges from the optimization of these different central bank loss functions.

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Childhood obesity is increasing at epidemic rates, and thus there is a need to target appropriate childhood behaviors that contribute to obesity. Many factors contribute to childhood weight status. The aim of this study was to look at relationships between parental rules to limit snacking while watching television and childhood weight status. The study looked at the presence of the behavior of snacking while watching television yesterday, congruence between child- and parent-reported perception of the presence of rules to limit snacking while watching television, and parent-reported frequency of children following rules to limit snacking while watching television. The outcomes were examined in a multi-ethnic population of children ages 6 to 9 years in Southeast Texas.^ This study was a cross-sectional secondary data analysis of the pilot program, Fun Families. This study examined baseline data from 202 parent-child dyads, which included both the control ( N= 101) and intervention groups (N= 101). Data were gathered using validated questions that were administered to 6-9 year old children and their primary caregiver (referred to as parent in the rest of the discussion) in Southeast Texas, between 2006 and 2008. The main study outcome was childhood weight status based on CDC BMI-for-age categories. The independent variables are (1) the presence of parental rules to limit snacking while watching television, (2) the congruence between child and parent about the presence of rules to limit snacking while watching television, and (3) the parent-reported frequency of the child following the rules to limit snacking while watching television. Chi-Square analyses were used to determine if weight status was different for (1) children who reported rules to limit snacking yesterday, (2) children who reported snacking, (3) children whose parents reported rules were present, and (4) those who had rule congruence with the parents not. Chi-Square analyses also examined if there was a difference in the presence of snacking behavior for children who reported rules, for children whose parents reported rules, and for those children who had congruence about rules. Linear regressions were used to determine if any of the studied variables predicted increased weight status or reported snacking while watching television yesterday.^ This study found that child-reported snacking yesterday was significantly different for children who reported rules (4.12, p= 0.04). Child-reported rules was significantly associated with (p= -0.14, α= 0.04) and predicted child-reported snacking yesterday (R 2 0.021, p= 0.04, t= -2.04, 95% CI -0.31, -0.01). There was statistical significant incongruence between child and parent perception about the presence of rules to limit snacking yesterday (15.06, p= 0.00). For this population, parent education level was significantly associated with child-reported rules (r= -0.16, p= 0.02), child-reported snacking yesterday (r= -0.15, p= 0.04), and parent-reported frequency of child following rules to limit snacking (r= 0.29, p= -0.01). Parent-reported speaking another language besides English at home was significantly associated with parent-reported rules (r= 0.17, p= 0.02).^ Although the studied variables did not show any significant associations or predictors for childhood weight status, the significant discord between parent and child perception about the presence of rules provides valuable information to future interventions that aim to reduce childhood weight status. Including the creation and enforcement of parental rules in interventions to reduce childhood weight status will be beneficial for future studies.^

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The primary interest was in predicting the distribution runs in a sequence of Bernoulli trials. Difference equation techniques were used to express the number of runs of a given length k in n trials under three assumptions (1) no runs of length greater than k, (2) no runs of length less than k, (3) no other assumptions about the length of runs. Generating functions were utilized to obtain the distributions of the future number of runs, future number of minimum run lengths and future number of the maximum run lengths unconditional on the number of successes and failures in the Bernoulli sequence. When applying the model to Texas hydrology data, the model provided an adequate fit for the data in eight of the ten regions. Suggested health applications of this approach to run theory are provided. ^

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It is still an open question how equilibrium warming in response to increasing radiative forcing - the specific equilibrium climate sensitivity S - depends on background climate. We here present palaeodata-based evidence on the state dependency of S, by using CO2 proxy data together with a 3-D ice-sheet-model-based reconstruction of land ice albedo over the last 5 million years (Myr). We find that the land ice albedo forcing depends non-linearly on the background climate, while any non-linearity of CO2 radiative forcing depends on the CO2 data set used. This non-linearity has not, so far, been accounted for in similar approaches due to previously more simplistic approximations, in which land ice albedo radiative forcing was a linear function of sea level change. The latitudinal dependency of ice-sheet area changes is important for the non-linearity between land ice albedo and sea level. In our set-up, in which the radiative forcing of CO2 and of the land ice albedo (LI) is combined, we find a state dependence in the calculated specific equilibrium climate sensitivity, S[CO2,LI], for most of the Pleistocene (last 2.1 Myr). During Pleistocene intermediate glaciated climates and interglacial periods, S[CO2,LI] is on average ~ 45 % larger than during Pleistocene full glacial conditions. In the Pliocene part of our analysis (2.6-5 Myr BP) the CO2 data uncertainties prevent a well-supported calculation for S[CO2,LI], but our analysis suggests that during times without a large land ice area in the Northern Hemisphere (e.g. before 2.82 Myr BP), the specific equilibrium climate sensitivity, S[CO2,LI], was smaller than during interglacials of the Pleistocene. We thus find support for a previously proposed state change in the climate system with the widespread appearance of northern hemispheric ice sheets. This study points for the first time to a so far overlooked non-linearity in the land ice albedo radiative forcing, which is important for similar palaeodata-based approaches to calculate climate sensitivity. However, the implications of this study for a suggested warming under CO2 doubling are not yet entirely clear since the details of necessary corrections for other slow feedbacks are not fully known and the uncertainties that exist in the ice-sheet simulations and global temperature reconstructions are large.

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The Baltic Sea is a semi-enclosed sea with a steady salinity gradient (3 per mil-30 per mil). Organisms have adapted to such low salinities, but are suspected to be more susceptible to stress. Within the frame of the integrated environmental monitoring BONUS + project "BEAST" the applicability of immune responses of the blue mussel was investigated in Danish coastal waters. The sampling sites were characterised by a salinity range (11-19 per mil) and different mixtures of contaminants (metals, PAHs and POPs), according to chemical analysis of mussel tissues. Variation partitioning (redundancy analysis) was applied to decompose salinity and contamination effects. The results indicated that cellular immune responses (total and differential haemocyte count, phagocytic activity and apoptosis) were mainly influenced by contaminants, whereas humoral factors (haemolytic activity) were mainly impacted by salinity. Hence, cellular immune functions may be suitable as biomarkers in monitoring programmes for the Baltic Sea and other geographic regions with salinity variances of the studied range.

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The ingestion of microplastics has been shown for a great variety of marine organisms. However, benthic marine mesoherbivores such as the common periwinkle Littorina littorea have been largely disregarded in studies about the effects of microplastics on the marine biota, probably because the pathway for microplastics to this functional group of organisms was not obvious. In laboratory experiments we showed that the seaweed Fucus vesiculosus retains suspended microplastics on its surface. The numbers of microplastics that adhered to the algae correlated with the concentrations of suspended particles in the water. In choice feeding assays L. littorea did not distinguish between algae with adherent microplastics and clean algae without microplastics, indicating that the snails do not recognize solid nonfood particles in the submillimeter size range as deleterious. In periwinkles that were feeding on contaminated algae, microplastics were found in the stomach and in the gut. However, no microplastics were found in the midgut gland, which is the principle digestive organ of gastropods. Microplastics in the fecal pellets of the periwinkles indicate that the particles do not accumulate rapidly inside the animals but are mostly released with the feces. Our results provide the first evidence that seaweeds may represent an efficient pathway for microplastics from the water to marine benthic herbivores.