Cloud computing promises high performance and cost-efficiency. However, most cloud infrastructures operate at a low utilization, which greatly adheres cost effectiveness. Previous works focus on seeking efficient virtual machine (VM) consolidation strategies to increase the utilization of virtual resources in production environment, but overlook the under-utilization of backup virtual resources...

Menopausal disorders may include shorter-term symptoms, such as hot flushes and night sweats (vasomotor symptoms, VMS) and longer-term chronic conditions such as cardiovascular disease (CVD), osteoporosis, and cognitive impairment. Initially, no clear link between the shorter-term symptoms and longer-term chronic conditions was evident and these disorders seemed to occur independently from each...

Given the costs associated with a cloud infrastructure, dynamic scheduling of virtual machines (VMs) can significantly lower costs while providing an acceptable service level. We develop a series of forecasting models for predicting demand for VMs in a cloud-based software used as a SaaS. These models are then used in a periodic-review provision model which determines how many VMs should be pro...

In this article, we present a finite element variational multiscale (VMS) method for incompressible flows based on two local Gauss integrations, and compare it with common VMS method which is defined by a low order finite element space Lh on the same grid as Xh for the velocity deformation tensor and a stabilization parameter a. The best algorithmic feature of our method is using two local Gaus...

Virtualization systems should be responsible for satisfying the service level objectives (SLOs) for each VM. Performance SLOs, in particular, are generally achieved by isolating the underlying hardware resources among the VMs. In this paper, we show through empirical evaluation that performance SLOs cannot be satisfied with current commercial SSDs. We show that garbage collection is the source ...

Time spent fishing is the effort metric often studied in fisheries but it may under-represent the effort actually expended by fishers. Entire fishing trips, from the time vessels leave port until they return, may prove more useful for examining trends in fleet dynamics, fisher behavior, and fishing costs. However, such trip information is often difficult to resolve. We identified ~30,000 trips ...

This paper considers the scenario where multiple clusters of Virtual Machines (i.e., termed Virtual Clusters) are hosted in a Cloud system consisting of a cluster of physical nodes. Multiple Virtual Clusters (VCs) cohabit in the physical cluster, with each VC offering a particular type of service for the incoming requests. In this context, VM consolidation, which strives to use a minimal number...

This paper describes the “Speech Recognition Virtual Kitchen” environment which has the goals to promote community sharing of research techniques, foster innovative experimentation, and provide solid reference systems as a tool for education, research, and evaluation with a focus on, but not restricted to, speech and language research. The core of the research infrastructure is the use of Virtu...

Virtual cloud network services let users have their own private networks in the public cloud. IPsec gateways are growing in importance accordingly as they provide VPN connections for customers to remotely access these private networks. Major cloud providers offer IPsec gateway functions to tenants using virtual machines (VMs) running a software IPsec gateway inside. However, dedicating individu...

Since Infrastructure-as-a-Service (IaaS) clouds contain many vulnerable virtual machines (VMs), intrusion detection systems (IDSes) should be run for all the VMs. IDS offloading is promising for this purpose because it allows IaaS providers to run IDSes outside of VMs without any cooperation of the users. However, offloaded IDSes cannot continue to monitor their target VM when the VM is migrate...