ON ARCHITECTURE FOR SLA-AWARE WORKFLOWS IN GRID ENVIRONMENTS

2005 ◽  
Vol 06 (03) ◽  
pp. 245-263 ◽  
Author(s):  
Dang Minh Quan ◽  
Odej Kao
Keyword(s):  
Data Transfer ◽  
A Priori ◽  
Research Work ◽  
Service Level ◽  
Explicit Statement ◽  
Grid Environments ◽  
Data Transfer Optimization ◽  
Deadline Constraints ◽  
Grid Resources

Service Level Agreements (SLAs) are currently one of the major research topics in Grid Computing, as they serve as a foundation for reliable and predictable Grids. SLAs define an explicit statement of expectations and obligations in a business relationship between provider and customer. Thus, SLAs should guarantee the desired and a-priori negotiated Quality of Service (QoS), which is a mandatory prerequisite for the Next Generation Grids. This development is proved by a manifold research work about SLAs and architectures for implementing SLAs in Grid environments. However, this work is mostly related to SLAs for standard, monolithic Grid jobs and neglects the dependencies between different steps of operation. The complexity of an SLA-specification for workflows grows significantly, as characteristics of correlated sub-jobs, the data transfer phases, the deadline constraints and possible failures have to be considered. Thus, an architecture for an SLA-aware workflow implementation needs sophisticated mechanisms for specification and management, sub-job mapping, data transfer optimization and fault reaction. Therefore, this paper presents an architecture for SLA-aware Grid workflows. The main contributions are an improved specification language for SLA-aware workflows, a mapping and optimization algorithm for sub-job assignment to Grid resources and a prototype implementation using standard middleware. Experimental measurements prove the quality of the development.

Achieving QoS in Highly Unreliable Grid Environments

2011 ◽  
pp. 156-180
Author(s):  
Antonios Litke
Keyword(s):  
Ad Hoc ◽  
Research Work ◽  
Service Differentiation ◽  
Research Activity ◽  
Simple Task ◽  
Grid Environments ◽  
Significant Research ◽  
Technological Means ◽  
Prioritization Scheme

Grids can form the basis for pervasive computing due to their ability of being open, scalable, and flexible to various changes (from topology changes to unpredicted failures of nodes). However, such environments are prone to failures due to their nature and need a certain level of reliability in order to provide viable and commercially exploitable solutions. This is causing nowadays a significant research activity which is focused on the topic of achieving certain levels of Quality of Service (QoS) in highly unreliable environments (such as mobile and ad hoc Grids). This study will focus on the state-of-the-art analysis of the QoS aspects in Grids and how this is achieved in terms of technological means. A small survey and related work will be also presented. A more detailed analysis on the features of unreliable environments such as mobile Grids will be described. An innovative and efficient mechanism will be described, which is especially designed for such environments, in order to enhance them with the QoS attributes of reliability (fault tolerance through replication of tasks) and service differentiation to the Grid users through a simple task prioritization scheme. The results that this recent research work is presenting are promising for the future advancement of Grid commercialization in such environments.

Security in Mobile Ad Hoc Networks

2009 ◽  
pp. 541-558 ◽  
Author(s):  
Ekata Mehul ◽  
Vikram Limaye
Keyword(s):  
Wireless Networks ◽  
Quality Of Service ◽  
Mobile Ad Hoc Networks ◽  
Ad Hoc ◽  
Data Transfer ◽  
Research Work ◽  
Secure Routing ◽  
Hoc Networks ◽  
Network Administrators

Securing a “Wireless Ad Hoc Network” (WAHN) is a major concern of network administrators. This is particularly so in case of the wireless networks due to their unique characteristics that varies from the traditional networks. For example, WAHN are vulnerable to internal as well as external attacks relatively easily, as compared with traditional networks, because of their ability to be accessible from anywhere within their range. Many solutions have been proposed in this area and they are also being continuously improved. Most of these solutions involve encryption; secure routing, quality of service, and so forth. However, each of these solutions is designed to operate in a particular situation; and it may fail to work successfully in other scenarios. This particular research work offers an alternate to improving the trustworthiness of the neighbourhood and securing the routing procedure. This security is achieved by dynamically computing the trust in neighbours and selecting the most secure route from the available ones for the data transfer. There is also a provision to detect the compromised node and virtually removing it from the network.

The Impact of Competitive Quasi-Market on Service Delivery in Benue State University, Makurdi Nigeria

GIS Business ◽  
2019 ◽  
Vol 14 (4) ◽  
pp. 85-98
Author(s):  
Idoko Peter
Keyword(s):  
Service Delivery ◽  
A Priori ◽  
Least Square ◽  
Secondary Source ◽  
State University ◽  
Ordinary Least Square ◽  
Negative Effect ◽  
The Impact ◽  
The Relationship

This research the impact of competitive quasi market on service delivery in Benue State University, Makurdi Nigeria. Both primary and secondary source of data and information were used for the study and questionnaire was used to extract information from the purposively selected respondents. The population for this study is one hundred and seventy three (173) administrative staff of Benue State University selected at random. The statistical tools employed was the classical ordinary least square (OLS) and the probability value of the estimates was used to tests hypotheses of the study. The result of the study indicates that a positive relationship exist between Competitive quasi marketing in Benue State University, Makurdi Nigeria (CQM) and Transparency in the service delivery (TRSP) and the relationship is statistically significant (p<0.05). Competitive quasi marketing (CQM) has a negative effect on Observe Competence in Benue State University, Makurdi Nigeria (OBCP) and the relationship is not statistically significant (p>0.05). Competitive quasi marketing (CQM) has a positive effect on Innovation in Benue State University, Makurdi Nigeria (INVO) and the relationship is statistically significant (p<0.05) and in line with a priori expectation. This means that a unit increases in Competitive quasi marketing (CQM) will result to a corresponding increase in innovation in Benue State University, Makurdi Nigeria (INVO) by a margin of 22.5%. It was concluded that government monopoly in the provision of certain types of services has greatly affected the quality of service experience in the institution. It was recommended among others that the stakeholders in the market has to be transparent so that the system will be productive to serve the society effectively

Fractal analysis in biology and medicine

2020 ◽  
pp. 85-92
Keyword(s):  
Fractal Analysis ◽  
A Priori ◽  
Research Work ◽  
Structure And Function ◽  
Review Article ◽  
Living Systems ◽  
Modern Biology ◽  
Additional Information ◽  
Important Additional Information ◽  
And Function

The review article discusses the possibilities of using fractal mathematical analysis to solve scientific and applied problems of modern biology and medicine. The authors show that only such an approach, related to the section of nonlinear mechanics, allows quantifying the chaotic component of the structure and function of living systems, that is a priori important additional information and expands, in particular, the possibilities of diagnostics, differential diagnosis and prediction of the course of physiological and pathological processes. A number of examples demonstrate the specific advantages of using fractal analysis for these purposes. The conclusion can be made that the expanded use of fractal analysis methods in the research work of medical and biological specialists is promising.

Distance Aware VM allocation process to minimize energy consumption in cloud computing

2019 ◽  
Vol 12 ◽  
Author(s):  
Gurpreet Singh ◽  
Manish Mahajan ◽  
Rajni Mohana
Keyword(s):  
Resource Allocation ◽  
Cloud Computing ◽  
Energy Consumption ◽  
Virtual Machine ◽  
Virtual Machines ◽  
Research Work ◽  
Service Level Agreement ◽  
Service Level ◽  
Physical Machine ◽  
Allocation Process

BACKGROUND: Cloud computing is considered as an on-demand service resource with the applications towards data center on pay per user basis. For allocating the resources appropriately for the satisfaction of user needs, an effective and reliable resource allocation method is required. Because of the enhanced user demand, the allocation of resources has now considered as a complex and challenging task when a physical machine is overloaded, Virtual Machines share its load by utilizing the physical machine resources. Previous studies lack in energy consumption and time management while keeping the Virtual Machine at the different server in turned on state. AIM AND OBJECTIVE: The main aim of this research work is to propose an effective resource allocation scheme for allocating the Virtual Machine from an ad hoc sub server with Virtual Machines. EXECUTION MODEL: The execution of the research has been carried out into two sections, initially, the location of Virtual Machines and Physical Machine with the server has been taken place and subsequently, the cross-validation of allocation is addressed. For the sorting of Virtual Machines, Modified Best Fit Decreasing algorithm is used and Multi-Machine Job Scheduling is used while the placement process of jobs to an appropriate host. Artificial Neural Network as a classifier, has allocated jobs to the hosts. Measures, viz. Service Level Agreement violation and energy consumption are considered and fruitful results have been obtained with a 37.7 of reduction in energy consumption and 15% improvement in Service Level Agreement violation.

Simulation and Emulation Tools for Fog Computing

2020 ◽  
Vol 13 ◽  
Author(s):  
Simar Preet Singh ◽  
Rajesh Kumar ◽  
Anju Sharma ◽  
S. Raji Reddy ◽  
Priyanka Vashisht
Keyword(s):  
Quality Of Service ◽  
Programming Languages ◽  
Traffic Management ◽  
Fog Computing ◽  
Research Work ◽  
Research Experience ◽  
Computing Paradigm ◽  
Quality Of Service Parameters ◽  
User Friendly

Background: Fog computing paradigm has recently emerged and gained higher attention in present era of Internet of Things. The growth of large number of devices all around, leads to the situation of flow of packets everywhere on the Internet. To overcome this situation and to provide computations at network edge, fog computing is the need of present time that enhances traffic management and avoids critical situations of jam, congestion etc. Methods: For research purposes, there are many methods to implement the scenarios of fog computing i.e. real-time implementation, implementation using emulators, implementation using simulators etc. The present study aims to describe the various simulation and emulation tools for implementing fog computing scenarios. Results: Review shows that iFogSim is the simulator that most of the researchers use in their research work. Among emulators, EmuFog is being used at higher pace than other available emulators. This might be due to ease of implementation and user-friendly nature of these tools and language these tools are based upon. The use of such tools enhance better research experience and leads to improved quality of service parameters (like bandwidth, network, security etc.). Conclusion: There are many fog computing simulators/emulators based on many different platforms that uses different programming languages. The paper concludes that the two main simulation and emulation tools in the area of fog computing are iFogSim and EmuFog. Accessibility of these simulation/emulation tools enhance better research experience and leads to improved quality of service parameters along with the ease of their usage.

scholarly journals Physiological parameters of mental health predict the emergence of post-traumatic stress symptoms in physicians treating COVID-19 patients

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
T. Dolev ◽  
S. Zubedat ◽  
Z. Brand ◽  
B. Bloch ◽  
E. Mader ◽  
...  
Keyword(s):  
Mental Health ◽  
Sleep Quality ◽  
Traumatic Stress ◽  
A Priori ◽  
Treatment Strategies ◽  
Physiological Measures ◽  
Post Traumatic Stress ◽  
Stress Symptoms ◽  
Post Traumatic

AbstractLack of established knowledge and treatment strategies, and change in work environment, may altogether critically affect the mental health and functioning of physicians treating COVID-19 patients. Thus, we examined whether treating COVID-19 patients affect the physicians’ mental health differently compared with physicians treating non-COVID-19 patients. In this cohort study, an association was blindly computed between physiologically measured anxiety and attention vigilance (collected from 1 May 2014 to 31 May 31 2016) and self-reports of anxiety, mental health aspects, and sleep quality (collected from 20 April to 30 June 2020, and analyzed from 1 July to 1 September 2020), of 91 physicians treating COVID-19 or non-COVID-19 patients. As a priori hypothesized, physicians treating COVID-19 patients showed a relative elevation in both physiological measures of anxiety (95% CI: 2317.69–2453.44 versus 1982.32–2068.46; P < 0.001) and attention vigilance (95% CI: 29.85–34.97 versus 22.84–26.61; P < 0.001), compared with their colleagues treating non-COVID-19 patients. At least 3 months into the pandemic, physicians treating COVID-19 patients reported high anxiety and low quality of sleep. Machine learning showed clustering to the COVID-19 and non-COVID-19 subgroups with a high correlation mainly between physiological and self-reported anxiety, and between physiologically measured anxiety and sleep duration. To conclude, the pattern of attention vigilance, heightened anxiety, and reduced sleep quality findings point the need for mental intervention aimed at those physicians susceptible to develop post-traumatic stress symptoms, owing to the consequences of fighting at the forefront of the COVID-19 pandemic.

scholarly journals A qualitative inquiry of access to and quality of primary healthcare in seven communities in East and West Africa (SevenCEWA): perspectives of stakeholders, healthcare providers and users

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Soter Ameh ◽  
Bolarinwa Oladimeji Akeem ◽  
Caleb Ochimana ◽  
Abayomi Olabayo Oluwasanu ◽  
Shukri F. Mohamed ◽  
...  
Keyword(s):  
Health Insurance ◽  
West Africa ◽  
Primary Healthcare ◽  
A Priori ◽  
Healthcare Providers ◽  
Health Coverage ◽  
Health Seeking ◽  
East And West ◽  
Universal Health

Abstract Background Universal health coverage is one of the Sustainable Development Goal targets known to improve population health and reduce financial burden. There is little qualitative data on access to and quality of primary healthcare in East and West Africa. The aim of this study was to describe the viewpoints of healthcare users, healthcare providers and other stakeholders on health-seeking behaviour, access to and quality of healthcare in seven communities in East and West Africa. Methods A qualitative study was conducted in four communities in Nigeria and one community each in Kenya, Uganda and Tanzania in 2018. Purposive sampling was used to recruit: 155 respondents (mostly healthcare users) for 24 focus group discussions, 25 healthcare users, healthcare providers and stakeholders for in-depth interviews and 11 healthcare providers and stakeholders for key informant interviews. The conceptual framework in this study combined elements of the Health Belief Model, Health Care Utilisation Model, four ‘As’ of access to care, and pathway model to better understand the a priori themes on access to and quality of primary healthcare as well as health-seeking behaviours of the study respondents. A content analysis of the data was done using MAXQDA 2018 qualitative software to identify these a priori themes and emerging themes. Results Access to primary healthcare in the seven communities was limited, especially use of health insurance. Quality of care was perceived to be unacceptable in public facilities whereas cost of care was unaffordable in private facilities. Health providers and users as well as stakeholders highlighted shortage of equipment, frequent drug stock-outs and long waiting times as major issues, but had varying opinions on satisfaction with care. Use of herbal medicines and other traditional treatments delayed or deterred seeking modern healthcare in the Nigerian sites. Conclusions There was a substantial gap in primary healthcare coverage and quality in the selected communities in rural and urban East and West Africa. Alternative models of healthcare delivery that address social and health inequities, through affordable health insurance, can be used to fill this gap and facilitate achieving universal health coverage.

scholarly journals Impact of flooding on health-related quality of life in England: results from the National Study of Flooding and Health

2020 ◽  
Vol 30 (5) ◽  
pp. 942-948
Author(s):  
Charlotte Robin ◽  
Charles Beck ◽  
Ben Armstrong ◽  
Thomas David Waite ◽  
G James Rubin ◽  
...  
Keyword(s):  
Quality Of Life ◽  
A Priori ◽  
National Study ◽  
Health Related Quality ◽  
Euroqol Group ◽  
Related Quality ◽  
Health Related ◽  
Anxiety Depression ◽  
The Impact

Abstract Background Flooding can have extensive effects on the health and wellbeing of affected communities. The impact of flooding on psychological morbidity has been established; however, the wider impacts of flooding exposure, including on health-related quality of life (HRQoL), have not been described. Methods Using data from the English National Study of Flooding and Health cohort, HRQoL 2 and 3 years post-flooding was assessed with the EuroQol Group EQ-5D-5L tool. Associations between exposure groups (flooding and disruption from flooding) and HRQoL were assessed, using ordinal and linear regression, adjusting for a priori confounders. Results For both 2 and 3 years post-flooding, the median HRQoL scores were lower in the flooded and disrupted groups, compared with unaffected respondents. A higher proportion of flooded and disrupted respondents reported HRQoL problems in most dimensions of the EQ-5D-5L, compared with unaffected respondents. In year 2, independent associations between exposure to flooding and experiencing anxiety/depression [adjusted odds ratio (aOR) 7.7; 95% CI 4.6–13.5], problems with usual activities (aOR 5.3; 95% CI 2.5–11.9) and pain/discomfort (aOR 2.4; 95% CI 1.5–3.9) were identified. These problems persisted 3 years post-flooding; associations between exposure to flooding and experiencing anxiety/depression (aOR 4.3; 95% CI 2.5–7.7), problems with usual activities (aOR 2.9; 95% CI 1.5–6.1) and pain/discomfort (aOR 2.5; 95% CI 1.5–4.2) were identified. Conclusions Exposure to flooding and disruption from flooding significantly reduces HRQoL. These findings extend our knowledge of the impacts of flooding on health, with implications for multi-agency emergency response and recovery plans.

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