Service level agreements-driven management of distributed applications in cloud computing environments

Advancements in cloud computing have enabled the proliferation of distributed applications, which require management and control of multiple services. However, without an efficient mechanism for scaling services in response to changing workload conditions, such as number of connected users, application performance might suffer, leading to violations of Service Level Agreements (SLA) and possible inefficient use of hardware resources. Combining dynamic application requirements with the increased use of virtualised computing resources creates a challenging resource Management context for application and cloud-infrastructure owners. In such complex environments, business entities use SLAs as a means for specifying quantitative and qualitative requirements of services. There are several challenges in running distributed enterprise applications in cloud environments, ranging from the instantiation of service VMs in the correct order using an adequate quantity of computing resources, to adapting the number of running services in response to varying external loads, such as number of users. The application owner is interested in finding the optimum amount of computing and network resources to use for ensuring that the performance requirements of all her/his applications are met. She/he is also interested in appropriately scaling the distributed services so that application performance guarantees are maintained even under dynamic workload conditions. Similarly, the infrastructure Providers are interested in optimally provisioning the virtual resources onto the available physical infrastructure so that her/his operational costs are minimized, while maximizing the performance of tenants’ applications. Motivated by the complexities associated with the management and scaling of distributed applications, while satisfying multiple objectives (related to both consumers and providers of cloud resources), this thesis proposes a cloud resource management platform able to dynamically provision and coordinate the various lifecycle actions on both virtual and physical cloud resources using semantically enriched SLAs. The system focuses on dynamic sizing (scaling) of virtual infrastructures composed of virtual machines (VM) bounded application services. We describe several algorithms for adapting the number of VMs allocated to the distributed application in response to changing workload conditions, based on SLA-defined performance guarantees. We also present a framework for dynamic composition of scaling rules for distributed service, which used benchmark-generated application Monitoring traces. We show how these scaling rules can be combined and included into semantic SLAs for controlling allocation of services. We also provide a detailed description of the multi-objective infrastructure resource allocation problem and various approaches to satisfying this problem. We present a resource management system based on a genetic algorithm, which performs allocation of virtual resources, while considering the optimization of multiple criteria. We prove that our approach significantly outperforms reactive VM-scaling algorithms as well as heuristic-based VM-allocation approaches.

Pelvic floor muscle displacement during voluntary and involuntary activation in continent and incontinent women: a systematic review.

INTRODUCTION Investigations of the dynamic function of female pelvic floor muscles (PFM) help us to understand the pathophysiology of stress urinary incontinence (SUI). Displacement measurements of PFM give insight into muscle activation and thus help to improve rehabilitation strategies. This systematic review (PROSPERO 2013: CRD42013006409) was performed to summarise the current evidence for PFM displacement during voluntary and involuntary activation in continent and incontinent women. METHODS MEDLINE, EMBASE, Cochrane and SPORTDiscus databases were searched using selected terminology reflecting the PICO approach. Screening of Google Scholar and congress abstracts added to further information. Original articles investigating PFM displacement were included if they reported on at least one of the aims of the review, e.g., method, test position, test activity, direction and quantification of displacement, as well as the comparison between continent and incontinent women. Titles and abstracts were screened by two reviewers. The papers included were reviewed by two individuals to ascertain whether they fulfilled the inclusion criteria and data were extracted on outcome parameters. RESULTS Forty-two predominantly observational studies fulfilled the inclusion criteria. A variety of measurement methods and calculations of displacement was presented. The sample was heterogeneous concerning age, parity and continence status. Test positions and test activities varied among the studies. CONCLUSIONS The findings summarise the present knowledge of PFM displacement, but still lack deeper comprehension of the SUI pathomechanism of involuntary, reflexive activation during functional activities. We therefore propose that future investigations focus on PFM dynamics during fast and stressful impact tasks.

Robustness of the Voluntary Breath-Hold Approach for the Treatment of Peripheral Lung Tumors Using Hypofractionated Pencil Beam Scanning Proton Therapy.

PURPOSE The safe clinical implementation of pencil beam scanning (PBS) proton therapy for lung tumors is complicated by the delivery uncertainties caused by breathing motion. The purpose of this feasibility study was to investigate whether a voluntary breath-hold technique could limit the delivery uncertainties resulting from interfractional motion. METHODS AND MATERIALS Data from 15 patients with peripheral lung tumors previously treated with stereotactic radiation therapy were included in this study. The patients had 1 computed tomographic (CT) scan in voluntary breath-hold acquired before treatment and 3 scans during the treatment course. PBS proton treatment plans with 2 fields (2F) and 3 fields (3F), respectively, were calculated based on the planning CT scan and subsequently recalculated on the 3 repeated CT scans. Recalculated plans were considered robust if the V95% (volume receiving ≥95% of the prescribed dose) of the gross target volume (GTV) was within 5% of what was expected from the planning CT data throughout the simulated treatment. RESULTS A total of 14/15 simulated treatments for both 2F and 3F met the robustness criteria. Reduced V95% was associated with baseline shifts (2F, P=.056; 3F, P=.008) and tumor size (2F, P=.025; 3F, P=.025). Smaller tumors with large baseline shifts were also at risk for reduced V95% (interaction term baseline/size: 2F, P=.005; 3F, P=.002). CONCLUSIONS The breath-hold approach is a realistic clinical option for treating lung tumors with PBS proton therapy. Potential risk factors for reduced V95% are small targets in combination with large baseline shifts. On the basis of these results, the baseline shift of the tumor should be monitored (eg, through image guided therapy), and appropriate measures should be taken accordingly. The intrafractional motion needs to be investigated to confirm that the breath-hold approach is robust.

Experiences with a voluntary surveillance system for early detection of equine diseases in Switzerland

Clinical observations made by practitioners and reported using web- and mobile-based technologies may benefit disease surveillance by improving the timeliness of outbreak detection. Equinella is a voluntary electronic reporting and information system established for the early detection of infectious equine diseases in Switzerland. Sentinel veterinary practitioners have been able to report cases of non-notifiable diseases and clinical symptoms to an internet-based platform since November 2013. Telephone interviews were carried out during the first year to understand the motivating and constraining factors affecting voluntary reporting and the use of mobile devices in a sentinel network. We found that non-monetary incentives attract sentinel practitioners; however, insufficient understanding of the reporting system and of its relevance, as well as concerns over the electronic dissemination of health data were identified as potential challenges to sustainable reporting. Many practitioners are not yet aware of the advantages of mobile-based surveillance and may require some time to become accustomed to novel reporting methods. Finally, our study highlights the need for continued information feedback loops within voluntary sentinel networks.

Why Do Economies Enter into Preferential Agreements on Trade in Services? Assessing the Potential for Negotiated Regulatory Convergence in Asian Services Markets

More than one-third of the World Trade Organization-notified services trade agreements that were in effect between January 2008 and August 2015 involved at least one South or Southeast Asian trading partner. Drawing on Baier and Bergstrand’s (2004) determinants of preferential trade agreements and using the World Bank’s database on the restrictiveness of domestic services regimes (Borchert, Gootiiz, and Mattoo 2012), we examine the potential for negotiated regulatory convergence in Asian services markets. Our results suggest that Asian economies with high levels of preexisting bilateral merchandise trade and wide differences in services regulatory frameworks are more likely candidates for services trade agreement formation. Such results lend support to the hypothesis that the heightened “servicification” of production generates demand for the lowered services input costs resulting from negotiated market openings.

Why do Countries Enter into Preferential Agreements on Trade in Services? Assessing the Potential for Negotiated Regulatory Convergence in Asian Services Markets

More than a third of the World Trade Organization (WTO)-notified services trade agreements (STAs) in effect over January 2008 - August 2015 have involved at least one (South or Southeast) Asian trading partner. Drawing on Baier and Bergstrand's (2004) determinants of preferential trade agreements and using the World Bank's database on the restrictiveness of domestic services regimes (Borchert et.al. 2012), we examine the potential for negotiated regulatory convergence in Asian services markets. Our results suggest that countries within Asia with high levels of pre-existing bilateral merchandise trade and wide differences in services regulatory frameworks are more likely candidates for STA formation. Such results lend support to the hypothesis that the heightened "servicification" of production generates a demand for the lowered service input costs resulting from negotiated market opening.

Exploring complementarities between goods and services trade in trade agreements

More than three decades of research on trade costs and goods trade have unveiled fundamental insights into the determinants, the nature and the consequences of goods trade agreements. A cottage literature has also evolved studying similar issues from a services trade perspective, but the two-way interaction between goods and services trade has not been explored formally. We bridge this gap by providing a formal treatment of the inter-linkages between goods and services trade. The model provides insights into how trade agreements impact goods and services trade. We also explore the impact of the complementarities of goods and services agreements on goods and services trade empirically using bilateral goods and services trade data for OECD and BRICS trading partners over 1995-2010.

Why do countries enter into preferential agreements on trade in Services? assessing the potential for negotiated regulatory convergence in asian Services markets

Presentation made by Pierre Sauvé and Anirudh Shingal at the Asian International Economists Network (AIEN) Workshop, Asian Development Bank, Manila.

Addressing climate change under preferential trade agreements: Towards alignment of carbon standards under the Transatlantic Trade and Investment Partnership

With its wide coverage of economic spheres and the variety of trade and investment measures currently under negotiation, the Transatlantic Trade and Investment Partnership opens windows of opportunity for advancing action on climate change. We examine possible avenues and international trade law implications for an alignment of carbon-related standards between the EU and the US. We compare EU and US carbon emissions standards for cars and argue that negotiators should strive for a mutual recognition of their equivalence for a transitional period, while pursuing the goal of full harmonization at the level of the highest standards of two parties at some date in the future. This could be a way to balance between economic and environmental interests and harness economic incentives for the benefit of climate.

Failure or Voluntary Exit? Reassessing the Female Underperformance Hypothesis

We reevaluate the female underperformance hypothesis by challenging the assumption that female-owned ventures are more likely to fail. Instead of equating exit with failure, we draw on exit literature and feminist theories to argue that female entrepreneurs are actually more likely than males to exit voluntarily. We argue for further gender differences by using an even more fine-grained conceptualization of entrepreneurial exit (failure, exit for personal reasons, and exit for other professional/financial opportunities). Post-hoc analyses also point to withingender heterogeneity depending on family status. A sample probe of 219 Spanish entrepreneurs who had exited their business supports our overall reasoning.

Why Do Some International Institutions Contain Strong Dispute Settlement Provisions: New Evidence from Preferential Trade Agreements

To understand why some international institutions have stronger dispute settlement mechanisms (DSMs) than others, we investigate the dispute settlement provisions of nearly 600 preferential trade agreements (PTAs), which possess several desirable case-selection features and are evoked more than is realized. We broaden the study of dispute settlement design beyond “legalization” and instead reorient theorizing around a multi-faceted conceptualization of the strength of DSMs. We posit that strong DSMs are first and foremost a rational response to features of agreements that require stronger dispute settlement, such as depth and large memberships. Multivariate empirical tests using a new data set on PTA design confirm these expectations and reveal that depth – the amount of policy change specified in an agreement – is the most powerful and consistent predictor of DSM strength, providing empirical support to a long-posited but controversial conjecture. Yet power also plays a sizeable role, since agreements among asymmetric members are more likely to have strong DSMs due to their mutual appeal, as are those involving the United States. Important regional differences also emerge, as PTAs across the Americas are designed with strong dispute settlement, as are Asian PTAs, which contradicts the conventional wisdom about Asian values and legalization. Our findings demonstrate that rationalism explains much of international institutional design, yet it can be enhanced by also incorporating power-based and regional explanations.