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Reward Scheduling for QoS in Cloud ApplicationsElnably, Ahmed 06 September 2012 (has links)
The growing popularity of multi-tenant, cloud-based computing platforms is increasing
interest in resource allocation models that permit flexible sharing of the underlying
infrastructure. This thesis introduces a novel IO resource allocation model
that better captures the requirements of paying tenants sharing a physical infrastructure.
The model addresses a major concern regarding application performance
stability when clients migrate from a dedicated to a shared platform. Specifically,
while clients would like their applications to behave similarly in both situations, traditional
models of fairness, like proportional share allocation, do not exhibit this
behavior in the context of modern multi-tiered storage architectures.
We also present a scheduling algorithm, the Reward Scheduler, that implements
the new allocation policy, by rewarding clients with better runtime characteristics,
resulting in benefits to both the clients and the service provider. Moreover, the Reward
scheduler also supports weight-based capacity allocation subject to a minimum
reservation and maximum limitation on the IO allocation for each task. Experimental
results indicate that the proposed algorithm proportionally allocates the system
capacity in proportion to their entitlements.
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Determining the depth of magma storage by investigation of samples from the eruption on La Palma 1971Svensson, Anna January 2013 (has links)
The Canary islands are formed by a slow moving hotspot, from Fuerteventura 20 Ma to el Hierro 1.2Ma years old and La Palma is in the shield building stage of evolution. La Palma had its last eruption 1971 and has had seven eruptions since 1430, which makes it the most active of the islands in our times. The samples consist of host lavas, basanites, and mafic/ultramafic and felsic xenoliths, alkali gabbros and syenites respectively. Minerals in the lavas and the alkali gabbro xenolith samples are clinopyroxene, olivine, amphibole and plagioclase, the clinopyroxenes are zoned. Forsterite content in the olivines increases at the rim for the xenoliths and decreases for the host lavas. While magnesium number in the clinopyroxenes decreases towards the rim. The Fe-Mg partitioning indicates that there were points of equilibrium between the clinopyroxenes and their host lavas, which was calculated to temperature, pressure and depth indicating 62-74km for the xenoliths and 23-35km for the host lavas. The temperatures and pressures were 1184-1205°C with 6-10 kbar for the host lavas compared to 1316-1341°C and 17-20 kbar for the xenoliths.
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IPU/LTB:a method for reducing effective memory latencyHarmon, C. Reid, Jr. 01 December 2003 (has links)
No description available.
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Thermal cycling effect on the nanoparticle distribution and specific heat of a carbonate eutectic with alumina nanoparticlesShankar, Sandhya 2011 May 1900 (has links)
The objective of this research was to measure the effect of thermal cycling on the nanoparticle distribution and specific heat of a nanocomposite material consisting of a eutectic of lithium carbonate and potassium carbonate and 1% by mass alumina nanoparticles. The material was subjected to thermal cycling in a stainless steel tube using a temperature controlled furnace. After thermal cycling, the stainless steel tube was sectioned into three equal parts – top, middle and bottom. Composite material samples were taken from the central region and near the wall region of each section.
The specific heat of this material in the temperature range of 290°C-397°C was measured using the Modulated Differential Scanning Calorimeter (MDSC) method. The concentration of alumina nanoparticles in this material was measured using neutron activation analysis. The average specific heat of the uncycled material was found to be 1.37 J/g°C.The average specific heat of the thermally cycled material was between 1.7-2.1 J/g°C. It was found that the concentration of the nanoparticle varied along the height of the sample tube. The nanoparticles tended to settle towards the bottom of the tube with thermal cycling. There was also migration of nanoparticles towards the wall of the sample tube with thermal cycling. Despite these gross movements of nanoparticles, there was no significant change in the specific heat of the nanocomposite due to thermal cycling.
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Storage Systems for Non-volatile Memory DevicesWu, Xiaojian 2011 August 1900 (has links)
This dissertation presents novel approaches to the use of non-volatile memory devices in building storage systems. There are many types of non-volatile memory devices, and they usually have better performance than regular magnetic hard disks in terms of throughput and latency. This dissertation focused on two of them, NAND flash memory and Phase Change Memory (PCM). This work consisted of two parts.
The first part was to design a high-performance hybrid storage system employing Solid State Drives that are build out of NAND flash memory and Hard Disk Drives. In this hybrid system, we proposed two different policies to improve its performance. One is to exploit the fact that the performances of Solid State Drive and Hard Disk Drive are asymmetric and the other is to exploit concurrency on multiple devices. We implemented prototypes in Linux and evaluate both policies in multiple workloads and multiple configurations. The results showed that the proposed approaches improve the performance significantly, and adapt to different configurations of the system under different workloads.
The second part was to implement a file system on a special class of memory devices, Storage Class Memory (SCM), which is both byte addressable and also nonvolatile, e.g. PCM. We claimed that both the existing regular file systems and the memory based file systems are not suitable for SCM, and proposed a new file system, called SCMFS, which is implemented on the virtual address space. In SCMFS, we utilized the existing memory management module in the operating system to do the block management. Our design keeps address space within a file contiguous to reduce the block management software. The simplicity of SCMFS not only makes it easy to implement, but also improves the performance. We implemented a prototype of SCMFS in Linux and evaluated its performance through multiple benchmarks.
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Impact of Cotton Harvesting and Storage Methods on Seed and Fiber QualityHamann, Mark Thomas 2011 December 1900 (has links)
There are currently two main types of machinery used for harvesting cotton in the United States, cotton pickers and cotton strippers with or without field cleaners. These different machine types package seed cotton with varying amounts of burrs, sticks, and leaves. Harvested cotton is placed in modules for storage prior to ginning. Recent developments in the industry include on-board module builders that package seed cotton as they harvest. This leads to three methods of storage: 1) traditional seed cotton modules, 2) half-modules, and 3) round modules utilized by harvesters with on-board module builders; all of these have different levels of packaging density.
Cotton is harvested under widely varying conditions throughout the country and the moisture content of seed cotton at the point of containerization can be an important factor in the final quality of the crop. Seed cotton is being stored for increasing periods of time before being processed by cotton gins.
The number of cotton gins in the U.S. has decreased while the production of cotton has increased. All cotton is harvested as it matures and the harvesting rate greatly exceeds the ginning rate. As a consequence of fewer gins, increased harvesting rates and increased quantities of cotton, the storage time of seed cotton prior to ginning has increased.
It is hypothesized that the impact of varying densities, varying trash contents, and increased storage times prior to ginning is impacting the quality of the cotton lint and seed. The goal of this research is to quantify the impacts of these factors.
The purpose of this research is to evaluate the effects of packaging seed cotton from any of the three different harvesting methods into varying types of storage as a function of differing moisture content and increased storage time. Results are indicated in terms of quality of both the fiber and the seed of ginned samples, as well as how the quality changes affect the value of the processed cotton.
Samples of seed cotton are sealed in plastic containers for up to three months at varying levels of moisture, density, and trash content. Temperature and oxygen levels are monitored during storage. Samples are ginned and cottonseed and fiber are analyzed.
The results of this research indicate that density does not affect the final quality of the lint and seed harvested. Increased moisture contents have a negative effect on both the quality and the value of the seed cotton, and this effect becomes more pronounced as the length of storage increases.
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Research for Storeage Information ManagmentLiou, Shuh-Ling 18 August 2003 (has links)
none
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Explicit deconvolution of wellbore storage distorted well test dataBahabanian, Olivier 25 April 2007 (has links)
The analysis/interpretation of wellbore storage distorted pressure transient test data remains one of the
most significant challenges in well test analysis. Deconvolution (i.e., the "conversion" of a variable-rate
distorted pressure profile into the pressure profile for an equivalent constant rate production sequence) has
been in limited use as a "conversion" mechanism for the last 25 years. Unfortunately, standard deconvolution
techniques require accurate measurements of flow-rate and pressure â at downhole (or sandface)
conditions. While accurate pressure measurements are commonplace, the measurement of sandface flowrates
is rare, essentially non-existent in practice.
As such, the "deconvolution" of wellbore storage distorted pressure test data is problematic.
In theory, this process is possible, but in practice, without accurate measurements of flowrates, this
process can not be employed. In this work we provide explicit (direct) deconvolution of wellbore storage
distorted pressure test data using only those pressure data. The underlying equations associated with each
deconvolution scheme are derived in the Appendices and implemented via a computational module.
The value of this work is that we provide explicit tools for the analysis of wellbore storage distorted
pressure data; specifically, we utilize the following techniques:
* Russell method (1966) (very approximate approach),
* "Beta" deconvolution (1950s and 1980s),
* "Material Balance" deconvolution (1990s).
Each method has been validated using both synthetic data and literature field cases and each method
should be considered valid for practical applications.
Our primary technical contribution in this work is the adaptation of various deconvolution methods for the
explicit analysis of an arbitrary set of pressure transient test data which are distorted by wellbore storage
â without the requirement of having measured sandface flowrates.
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Analysis of the financial accounting sties on the World Wide Web /Bachvarov, Boris Lyobomirov. January 2002 (has links) (PDF)
Thesis (M.S.)--Naval Postgraduate School, 2002. / Thesis advisor(s): Doug Moses, Tony Kendal. Also available online.
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The role of power and energy demands in hybrid vehiclesConley, John Jason. January 2002 (has links)
Thesis (M.S.)--West Virginia University, 2002. / Title from document title page. Document formatted into pages; contains xi, 100 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 69-72).
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