158 research outputs found
Fast flux botnet detection framework using adaptive dynamic evolving spiking neural network algorithm
A botnet, a set of compromised machines controlled
distantly by an attacker, is the basis of numerous security threats around the world. Command and Control servers are the backbones of botnet communications, where the bots and botmasters send report and attack orders to each other. Botnets are also categorized according to their C&C protocols.
A Domain Name System method known as Fast-Flux Service Network (FFSN) – a special type of botnet – has been engaged by bot herders to cover malicious botnet
activities and increase the lifetime of malicious servers by quickly changing the IP addresses of the domain name over time. Although several methods have been suggested for detecting FFSNs, they have low detection accuracy especially with zero-day domain. In this
research, we propose a new system called Fast Flux Killer System (FFKS) that has the ability to detect FF-Domains in online mode with an implementation constructed on Adaptive Dynamic evolving Spiking Neural Network (ADeSNN). The proposed system proved
its ability to detect FF domains in online mode with high detection accuracy (98.77%) compare with other algorithms, with low false positive and negative rates respectively. It is also proved a high level of performance. Additionally, the proposed adaptation of the algorithm enhanced and helped in the parameters customization
process
Enhanced Position Verification for VANETs using Subjective Logic
The integrity of messages in vehicular ad-hoc networks has been extensively
studied by the research community, resulting in the IEEE~1609.2 standard, which
provides typical integrity guarantees. However, the correctness of message
contents is still one of the main challenges of applying dependable and secure
vehicular ad-hoc networks. One important use case is the validity of position
information contained in messages: position verification mechanisms have been
proposed in the literature to provide this functionality. A more general
approach to validate such information is by applying misbehavior detection
mechanisms. In this paper, we consider misbehavior detection by enhancing two
position verification mechanisms and fusing their results in a generalized
framework using subjective logic. We conduct extensive simulations using VEINS
to study the impact of traffic density, as well as several types of attackers
and fractions of attackers on our mechanisms. The obtained results show the
proposed framework can validate position information as effectively as existing
approaches in the literature, without tailoring the framework specifically for
this use case.Comment: 7 pages, 18 figures, corrected version of a paper submitted to 2016
IEEE 84th Vehicular Technology Conference (VTC2016-Fall): revised the way an
opinion is created with eART, and re-did the experiments (uploaded here as
correction in agreement with TPC Chairs
The cost benefit of algal technology for combined CO2 mitigation and nutrient abatement
The use of microalgae culture technology (MCT) for mitigating CO2 emissions from flue gases and nutrient discharges from wastewater whilst generating a biofuel product is considered with reference to the cost benefit offered. The review examines the most recent MCT literature (post 2010) focused on the algal biomass or biofuel production cost.
The analysis reveals that, according to published studies, biofuel cost follows an approximate inverse relationship with algal or lipid productivity with a minimum production cost of $1 L−1 attained under representative conditions. A 35–86% cost reduction is reported across all studies from the combined harnessing of CO2 and nutrients from waste sources. This compares with 12–27% for obviating fertiliser procurement through using a wastewater nutrient source (or else recycling the liquor from the extracted algal biomass waste), and 19–39% for CO2 fixation from a flue gas feed.
Notwithstanding the above, economic competitiveness with mineral fuels appears to be attainable only under circumstances which also feature:
a)
The inclusion of cost and environmental benefits from wastewater treatment (such as the energy and/or greenhouse gas emissions benefit from nutrient and CO2 discharge abatement), and/or
a)
Multiple installations over an extended geographic region where flue gas and wastewater sources are co-located
The Chemical Speciation of Trace-Metals in Street Dusts of Irbid, Jordan
Abstract Street dust samples were collected from different locations in Irbid city, Jordan. The concentrations of Pb, Cu, Zn, Cd, Ni, Mn, Cr and Al in these samples were determined usin
Obstacles of Administrative Creativity Among the Principals of Public Schools in Amman City from their Point of View
The aim of this study is to identify the obstacles of administrative creativity among the principals of public schools in Amman City from their point of view. With that, the descriptive survey methodology was adopted. The sample of the study consisted of (105) male and female principals selected randomly. To achieve the objective of the study, a 30-item questionnaire distributed over (3) areas was formatted.The results of the study showed that the obstacles of administrative creativity among the principals of public schools in Amman City from their point of view for various fields were at a medium degree, where the field of environmental obstacles ranked first, followed by the field of organizational obstacles in the second place, followed by the field of personal obstacles in the third and last rank.The results showed that there were statistically significant differences for both sex variable in favor of males and experience variable in favor of those with more than ten years of experience.In the light of the researcher's findings: Work to link social and cultural institutions in the community in order to unite efforts to contribute to raising awareness of community members of the importance of creativity and innovation in school work, and organize programs and training courses to develop creativity skills. Promote positive communication at all levels to facilitate proposals for the development and improvement of performance, and the need to provide integrated administrative staff in each school to reduce school workload and provide an opportunity for creativity and innovation. Keywords: Administrative Creativity, Obstacles, Principals, Amman City. DOI: 10.7176/JEP/10-36-04 Publication date: December 31st 201
Evaluation of the United Kingdom-Primary Biliary Cholangitis and Global Primary Biliary Cholangitis Group Prognostic Models for Primary Biliary Cholangitis Patients Treated with Ursodeoxycholic Acid in the U.S. Population
JGH Open: An open access journal of gastroenterology and hepatology published by Journal of Gastroenterology and Hepatology Foundation and John Wiley and Sons Australia, Ltd. Background and Aim: The United Kingdom-primary biliary cholangitis (UK-PBC) and global primary biliary cholangitis group (GLOBE) prognostic models have been recently developed to predict long-term outcomes in primary biliary cholangitis (PBC). However, these predictive scores have not yet been well evaluated in the U.S. population. Methods: We retrospectively reviewed newly diagnosed PBC patients at the Cleveland Clinic between November 1998 and February 2017. Adverse events were defined as liver transplantation, liver-related mortality, and all-cause mortality. Transplant-free survival (TFS) was estimated using the Kaplan–Meier method. Predictive performances of all prognostic models were evaluated using the C-statistic. Results: We identified 352 patients who used ursodeoxycholic acid therapy. Of them, 311 (88.4%) only had PBC, while 41 (11.6%) were diagnosed with PBC-autoimmune hepatitis overlap. A total of 22 (6%), 47 (13%), and 55 (16%) patients had adverse events within 5, 10, and 15 years after diagnosis, respectively. In patients with PBC only, the C-statistic in predicting 15-year adverse events was 0.75 per GLOBE compared to 0.74 per UK-PBC (P = 0.94), 0.73 per Rotterdam (P = 0.44), 0.66 per Barcelona (P = 0.004), 0.65 per Paris 1 (P = 0.005), 0.62 per Paris 2 (P \u3c 0.0001), 0.60 per Toronto (P \u3c 0.0001), and 0.60 per Mayo (P \u3c 0.0001) scores. Median follow-up was 9.2 years. Ten-year TFS for patients who had optimal versus suboptimal treatment response was 92 versus 74% per Paris 1 (P \u3c 0.0001), 95 versus 79% per Paris 2 (P = 0.0002), 93 versus 65% per Barcelona (P \u3c 0.0001), and 96 versus 68% per Rotterdam (P \u3c 0.0001) risk scores, respectively. Conclusion: In our cohort of PBC patients, the UK-PBC and GLOBE scores were both accurate and reasonably valid prognostic models in the U.S. population
Phone-based audience response system as an adjunct in orthodontic teaching of undergraduate dental students: a cross-over randomised controlled trial
Background:
The advent of electronic teaching facilities improves tutor-student communication. This study aims to explore the effectiveness of Phone-Based Audience Response System (PB-ARS), as an adjunctive pedagogy tool to enhance the retention of orthodontic information by dental students; and to explore the students’ perception of PB-ARS.
Methods:
This cross-over clustered randomised control trial included 34 males who were in the final year of their undergraduate dental training. Participants were allocated to one of two event groups (G1 and G2) using computer-generated randomisation. Both groups simultaneously attended two different traditional lectures (L 1 and L2) a week apart. During L1, PB-ARS was used as an adjunct to conventional presentation to teach G1 participants, (PB-ARS group) while G2’s participants acted as a control group (CG), and were taught using a traditional presentation. In the second week (L2), the interventions were crossed-over. Participants from both groups completed pre- and post-lecture multiple-choice questionnaires (MCQ) to assess their short-term retention of information. Their performance in the final MCQ exam (10 weeks following L2) was tracked to assess the long-term retention of the information. Participants also completed post-lecture questionnaires to evaluate their perceptions.
Results:
Twenty-nine and 31 participants from the CG and PB-ARS group completed this trial, respectively. Although 87.5% of students in the PB-ARS group showed an improvement in their immediate post-lecture scores compared with 79.3% for the CG, it was statistically insignificant (p = 0.465). Similarly, the intervention showed an insignificant effect on the long-term retention of the knowledge (p = 0.560).
There was a mildly but favourable attitude of students towards the use of PB-ARS. However, the difference in the overall level of satisfaction between both groups was statistically insignificant (p = 0.183).
Conclusion:
PB-ARS has a minimal and insignificant effect on the short- and long-term retention of orthodontic knowledge by male undergraduate dental students. PB-ARS was the preferred adjunct tool to conventional classroom teaching. Due to the limitations of this trial, a long-term randomised controlled trial with a larger sample size is recommended
Techniques for Arbuscular Mycorrhiza Inoculum Reduction
It is well established that arbuscular mycorrhizal (AM) fungi can play a significant role in sustainable crop production and environmental conservation. With the increasing awareness of the ecological significance of mycorrhizas and their diversity, research needs to be directed away from simple records of their occurrence or casual speculation of their function (Smith and Read 1997). Rather, the need is for empirical studies and investigations of the quantitative aspects of the distribution of different types and their contribution to the function of ecosystems.
There is no such thing as a fungal effect or a plant effect, but there is an interaction between both symbionts. This results from the AM fungi and plant community size and structure, soil and climatic conditions, and the interplay between all these factors (Kahiluoto et al. 2000). Consequently, it is readily understood that it is the problems associated with methodology that limit our understanding of the functioning and effects of AM fungi within field communities.
Given the ubiquous presence of AM fungi, a major constraint to the evaluation of the activity of AM colonisation has been the need to account for the indigenous soil native inoculum. This has to be controlled (i.e. reduced or eliminated) if we are to obtain a true control treatment for analysis of arbuscular mycorrhizas in natural substrates. There are various procedures possible for achieving such an objective, and the purpose of this chapter is to provide details of a number of techniques and present some evaluation of their advantages and disadvantages.
Although there have been a large number of experiments to investigated the effectiveness of different sterilization procedures for reducing pathogenic soil fungi, little information is available on their impact on beneficial organisms such as AM fungi. Furthermore, some of the techniques have been shown to affect physical and chemical soil characteristics as well as eliminate soil microorganisms that can interfere with the development of mycorrhizas, and this creates difficulties in the interpretation of results simply in terms of possible mycorrhizal activity.
An important subject is the differentiation of methods that involve sterilization from those focussed on indigenous inoculum reduction. Soil sterilization aims to destroy or eliminate microbial cells while maintaining the existing chemical and physical characteristics of the soil (Wolf and Skipper 1994). Consequently, it is often used for experiments focussed on specific AM fungi, or to establish a negative control in some other types of study. In contrast, the purpose of inoculum reduction techniques is to create a perturbation that will interfere with mycorrhizal formation, although not necessarily eliminating any component group within the inoculum. Such an approach allows the establishment of different degrees of mycorrhizal formation between treatments and the study of relative effects.
Frequently the basic techniques used to achieve complete sterilization or just an inoculum reduction may be similar but the desired outcome is accomplished by adjustments of the dosage or intensity of the treatment. The ultimate choice of methodology for establishing an adequate non-mycorrhizal control depends on the design of the particular experiments, the facilities available and the amount of soil requiring treatment
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