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In this paper, we address the resource and virtual machine instance hour minimization problem for directed-acyclic-graph based deadline constrained applications deployed on computer clouds. The allocated resources and instance hours on computer clouds must: (1) guarantee the satisfaction of a deadline constrained application's end-to-end deadline; (2) ensure that the number of virtual machine (VM) instances allocated to the application is minimized; (3) under the allocated number of VM instances, determine application execution schedule that minimizes the application's makespan; and (4) under the decided application execution schedule, determine a VM operation schedule, i.e., when a VM should be turned on or off, that minimizes total VM instance hours needed to execute the application. We first give lower and upper bounds for the number of VM instances needed to guarantee the satisfaction of a deadline constrained application's end-to-end deadline. Based on the bounds, we develop a heuristic algorithm called minimal slack time and minimal distance (MSMD) algorithm that finds the minimum number of VM instances needed to guarantee the application's deadline and schedules tasks on the allocated VM instances so that the application's makespan is minimized. Once the application execution schedule and the number of VM instances needed are determined, the proposed VM instance hour minimization (IHM) algorithm is applied to further reduce the instance hours needed by VMs to complete the application's execution. Our experimental results show that the MSMD algorithm can guarantee applications' end-to-end deadlines with less resources than the HEFT [32], MOHEFT [16], DBUS [9], QoS-base [40] and Auto-Scaling [25] heuristic scheduling algorithms in the literature. Furthermore, under allocated resources, the MSMD algorithm can, on average, reduce an application's makespan by 3.4 percent of its deadline. In addition, with the IHM algorithm we can effectively reduce the application's execution instance hours compared with when IHM is not applied.

The periodic task set assignment problem in the context of multiple processors has been studied for decades. Different heuristic approaches have been proposed, such as the Best-Fit (BF), the First-Fit (FF), and the Worst-Fit (WF) task assignment algorithms. However, when processors are not dedicated but only periodically available to the task set, whether existing approaches still provide good performance or if there is a better task assignment approach in the new context are research problems which, to our best knowledge, have not been studied by the real-time research community. In this paper, we present the Best-Harmonically-Fit (BHF) task assignment algorithm to assign periodic tasks on multiple periodic resources. By periodic resource we mean that for every fixed time interval, i.e., the period, the resource always provides the same amount of processing capacity to a given task set. Our formal analysis indicates that if a harmonic task set is also harmonic with a resource's period, the resource capacity can be fully utilized by the task set. Based on this analysis, we present the Best-Harmonically-Fit task assignment algorithm. The experimental results show that, on average, the BHF algorithm results in 53.26 , 42.54 , and 27.79 percent higher resource utilization rate than the Best-Fit Decreasing (BFD), the First-Fit Decreasing (FFD), and the Worst-Fit Decreasing (WFD) task assignment algorithms, respectively; but comparing to the optimal resource utilization rate found by exhaustive search, it is about 11.63 percent lower.

Cloud bursting is one of the key research topics in the cloud computing communities. A well designed cloud bursting module enables private clouds to automatically launch virtual machines (VMs) to public clouds when more resources are needed. One of the main challenges in developing a cloud bursting module is to decide when and where to launch a VM so that all resources are most effectively and efficiently utilized and the system performance is optimized. However, based on system operational data obtained from FermiCloud, a private cloud developed by the Fermi National Accelerator Laboratory for scientific workflows, the VM launching overhead is not a constant. It varies with physical resource utilization, such as CPU and I/O device utilizations, at the time when a VM is launched. Hence, to make judicious decisions as to when and where a VM should be launched, a VM launching overhead reference model is needed. In this paper, we first develop a VM launching overhead reference model based on operational data we have obtained on FermiCloud. Second, we apply the developed reference model on FermiCloud and compare calculated VM launching overhead values based on the model with measured overhead values on FermiCloud. Our empirical results on FermiCloud indicate that the developed reference model is accurate. We believe, with the guidance of the developed reference model, efficient resource allocation algorithms can be developed for cloud bursting process to minimize the operational cost and resource waste.

In this age of technology, building quality software is essential to competing in the business market. One of the major principles required for any quality and business software product for value fulfillment is reliability. Estimating software reliability early during the software development life cycle saves time and money as it prevents spending larger sums fixing a defective software product after deployment. The Software Reliability Growth Model (SRGM) can be used to predict the number of failures that may be encountered during the software testing process. In this paper we explore the advantages of the Grey Wolf Optimization (GWO) algorithm in estimating the SRGM’s parameters with the objective of minimizing the difference between the estimated and the actual number of failures of the software system. We evaluated three different software reliability growth models: the Exponential Model (EXPM), the Power Model (POWM) and the Delayed S-Shaped Model (DSSM). In addition, we used three different datasets to conduct an experimental study in order to show the effectiveness of our approach.

Paullinia yoco R.E. Schult. & Killip (Sapindaceae) or 'yoco', is a liana (a woody vine) used traditionally by indigenous peoples of the upper Amazon region as a stimulating beverage, because it contains both caffeine and theobromine. However, as the wild plants become increasingly rare and hard to find because of permanent settlement within a much-reduced territory, there is growing interest among indigenous tribes to learn how to successfully cultivate it for community consumption and potentially as a cash crop. To date, there has been very little research conducted on the stimulant chemical composition of the liana and biochemical variation within- and between plants. This paper provides the results of chemical (high-performance liquid chromatography) analysis of caffeine and theobromine concentrations of multiple samples of phloem and leaf material from 18 Paullinia yoco lianas. Caffeine values ranged from 0.1% to 3.6% with a significantly higher amount in the stem phloem material than the leaf material, and there was a positive linear correlation between stem diameter and caffeine concentration (% dry weight). Although the highest theobromine level was found in leaf material (1.8%), overall there was no significant difference between phloem and leaf material, and no correlation between stem diameter and theobromine concentration. Finally, we found a significant amount of variance of both caffeine and theobromine between individual plants. These results are important, first because they shed light on the apparently conflicting previous reports on P. yoco caffeine and theobromine content; and second, they provide important clues about the phytochemical architecture of P. yoco which in turn has important implications for the design of a cultivation strategy for local indigenous communities to potentially produce a yet-to-be domesticated plant of substantial market potential.

The bacteriophage population is large, dynamic, ancient, and genetically diverse. Limited genomic information shows that phage genomes are mosaic, and the genetic architecture of phage populations remains ill-defined. To understand the population structure of phages infecting a single host strain, we isolated, sequenced, and compared 627 phages of Mycobacterium smegmatis. Their genetic diversity is considerable, and there are 28 distinct genomic types (clusters) with related nucleotide sequences. However, amino acid sequence comparisons show pervasive genomic mosaicism, and quantification of inter-cluster and intra-cluster relatedness reveals a continuum of genetic diversity, albeit with uneven representation of different phages. Furthermore, rarefaction analysis shows that the mycobacteriophage population is not closed, and there is a constant influx of genes from other sources. Phage isolation and analysis was performed by a large consortium of academic institutions, illustrating the substantial benefits of a disseminated, structured program involving large numbers of freshman undergraduates in scientific discovery.

À la limite: la vie et la carrière de Zacharie de Celers

Die Projektion Gerhard Mercators setzte Maßstäbe in der Kartographie und wurde zum weltweiten Standard, bis sie im 20. Jahrhundert in die Kritik geriet und sukzessive abgelöst wurde. Dieser Band, hervorgegangen aus einer internationalen Tagung aus Anlass des 500. Geburtstags Mercators, nimmt den Gelehrten und sein Werk im Kontext mittelalterlicher und frühneuzeitlicher Diskurse, Netzwerke und Dimensionen der Wissensproduktion in den Blick. Am Standort Duisburg war Mercator auf Informationen aus aller Welt angewiesen, die er durch ein briefliches Kommunikationsnetz und über Vermittlung durch Abraham Ortelius erhielt. Der Selbstverlag, der auf der Mitarbeit der Familie basierte, produzierte und vertrieb das umfangreiche Werk, das weit mehr als Karten und Globen umfasste. Die Rezeption des Werks, die Nutzung und Popularisierung seiner Karten und Globen werden in diesem Band ebenso beleuchtet wie die Wirkung seiner wissenschaftlichen Erkenntnisse bis in unsere Gegenwart.

In Alain Chartier: Père de l'éloquence française contributors explore the diverse literary production of this influential late-medieval writer, whose concern with personal and political ethics and renovation of poetic form inspired generations of writers, and still resonate with modern readers.

Local governments are a vital component in the national effort to promote sensible methods for community development, growth and social justice. The benefits and challenges of sustainable development have become apparent as more local governments initiate programs to address economic, environmental and social equity issues. This research investigates county and municipal government efforts toward sustainable development using survey information for local governments in the southern United States. Survey responses were analyzed to examine whether local governments “practice what they preach” in terms of actually implementing the sustainable policies proclaimed to be important to their operations. Overall, results suggest local governments do place these policies into action for environmental and social justice issues. In addition, the analysis explores the impact of population size, geographic area and form of government on sustainable development. Measuring the implementation of sustainable policies in terms of dollars, however, proves difficult because there is no consistency among municipalities with regard to reporting the amount of dollars (federal or local) spent in support of sustainability efforts.

Delivery of a quality introductory accounting course is essential for schools of business. The first step in revitalization and improvement of the course is to identify factors suggested to be empirically related to succeessful completion. Accounting major status is of particular interest. While it has long been anecdotally observed and logically expected that accounting majors would earn higher grades in introductory accounting, it is rarely addressed in empirical studies. To investigate the impact of accounting major status on performance in introductory accounting, a sample of 398 students exposed to the same professor, text, teaching and examination format over five-years was gathered. Results suggest accounting major status was in fact a significant positive predictor of grades earned in the class controlling for three additional variables (i.e., grade point average, mathematics background and previous experience in the course). These results could be used to support the creation of an honors section(s) of accounting which could include a more rigorous curriculum taught with real life cases. Previous research supported the concept of an honors program from students, faculty and potential employers. In addition, the results suggest requiring a minimum grade point average and the completion of mathematics requirement before taking introductory accounting.

The purpose of this study is to explore the commitment of local governments to environmental programs when fiscal distress is predicted. We hypothesize that commitment to environmental programs diminishes when the local government is experiencing fiscal distress. The regression model results indicate that local governments with high levels of debt were less likely to I mplement environmental programs and that a larger population and higher revenue are factors directly related to the commitment of local government to environmental programs. Communities that are more populous and less fiscally stressed are more likely to benefit from a local government that implements and sustains environmental programs. These results have implications for the stakeholders of local communities and broader implications for the global effort toward environmental protection and sustainable communities.

The reporting of non-Generally Accepted Accounting Principles Measures (non-GAAP) by U.S. publically traded companies is not new but it has recently come under increased scrutiny by the United States Securities and Exchange Commission (SEC). This case presents a specific example of this scrutiny in the form of Tesla, Inc.’s quarterly earnings announcements and Tesla’s subsequent correspondence with the SEC. This case requires students to answer relevant questions about GAAP vs Non GAAP reporting, generally in the form of a research memo, with references to applicable SEC regulations and guidance on the use and reporting of non-GAAP measures.

With a dynamical mass of 3 M Jup, the recently discovered giant planet AF Lep b is the lowest-mass imaged planet with a direct mass measurement. Its youth and spectral type near the L/T transition make it a promising target to study the impact of clouds and atmospheric chemistry at low surface gravities. In this work, we present JWST/NIRCam imaging of AF Lep b. Across two epochs, we detect AF Lep b in F444W (4.4 μm) with signal-to-noise ratios of 9.6 and 8.7, respectively. At the planet’s separation of 320 mas during the observations, the coronagraphic throughput is ≈7%, demonstrating that NIRCam’s excellent sensitivity persists down to small separations. The F444W photometry of AF Lep b affirms the presence of disequilibrium carbon chemistry and enhanced atmospheric metallicity. These observations also place deep limits on wider-separation planets in the system, ruling out 1.1 M Jup planets beyond 15.6 au (0.″58), 1.1 M Sat planets beyond 27 au (1″), and 2.8 M Nep planets beyond 67 au (2.″5). We also present new Keck/NIRC2 imaging of AF Lep b; combining this with the two epochs of F444W photometry and previous Keck photometry provides limits on the long-term 3–5 μm variability of AF Lep b on timescales of months to years. AF Lep b is the closest-separation planet imaged with JWST to date, demonstrating that planets can be recovered well inside the nominal (50% throughput) NIRCam coronagraph inner working angle.

Nature-based education has been increasingly recognized as a socially responsible approach to nurture curiosities in the hands, heads, and hearts of children. Research in the last ten years suggests that children who attend forest preschools, as opposed to traditional preschools, demonstrate growth in all domains of early childhood development. Domains include cognitive growth, executive functioning, physical development, linguistic proficiency, and socio-emotional well-being. In addition to cultivating these areas two Waldkindergarten or forest schools, studied in this chapter nourish as additional component—connectedness, compassion, and care for nature. There has been a steady increase in nature-based preschool programs as alternative approaches to traditional, indoor classrooms. With the expansion of programs, globally, and heightened awareness around environmental issues in the Anthropocene, nature-based education is increasingly recognized for cultivating socially responsible approaches that yield sustainable practices. This chapter reports on an exploratory study that synthesized two fieldwork experiences in German Wald-kindergarten, one in the north near Denmark and one in south, near the foothills of the Alps. Through a qualitative, thematic analysis of fieldnotes of direct and partici-pant observation, interviews with facilitators and analysis of student-created artifacts, this chapter explores how time in nature can be reconceived as a space to cultivate a connectedness to nature that fosters a commitment to conservation and sustain-ability. Primary goals of this research are to identify practices that center children learning with nature and, subsequently, to reconceptualize forest school practices in contexts outside of northern Europe. This research interrogates ways in which forest schools serve as spaces to engage in work around environmental stewardship while problematizing the accessibility of nature-based programs. Whilst reflecting upon lessons from Waldkindergarten, this chapter explores how nature-based Education provides opportunities towards a sustainable future for cultivating children’s curiosities in timeless traditions. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.