26 research outputs found
Multi Hop Transmission in IEEE 802.11 Low Rate Ad Hoc Network Using ARP-Route
Ad hoc networks are becoming more important in the modern complex environment. The ad hoc network can be used to instantly connect to the local or remote networks such as
the Internet without the need of pre-existing infrastructure or centralized administration. The users of the network together will establish the infrastructure. The disadvantage of wireless communication is that it has limited range of radio transmission. Due to this, multiple network âhopsâ are needed for one device to exchange data with another device across the network. In an ad hoc network, these devices will not only operate as a host but also as a router to forward the packets. There are varieties of routing protocols targeted for this environment that have been proposed and developed. However, most of them suffer from high overhead data traffic. The main purpose of this project is to implement the ad hoc network with the existing network protocol that had
already been used in network environment which is the Address Resolution Protocol (ARP). ARP was designed to announce or find MAC addresses. The novelty of this study is that we have extended the usage of the ARP protocol to act as routing protocol in wireless ad hoc network. The ARP route provides two new operation types, ARP Forward Request and ARP Forward Reply to allow the multihop transmission using intermediate nodes to forward the request and reply. These two operation types only used the current operation codes which are â0x0001â for request and â0x0002â for reply. This work on the routing protocol creates a new operation code for the ARP forwarding scheme which is
â0x000câ for forwarding. We have successfully managed to create a multi hop transmission in an ad hoc network by using the current existing operation code for the ARP forwarding. The work scope focus only on proving that the method can be applied hence it is not necessarily to prove the effectiveness of this proposed method yet. Therefore, the outcome of the study shows that the data can be sent through multi hop transmission until it reaches the destination. The 802.11b test-bed has been configured
and the ARP routing protocol has been implemented for multi
hop transmission. The experiment in the open space provides the comparison of environment with obstacles and without obstacles. We manage to get more than 50% of packet receive at a place with no obstacles and more than 45% in a place with obstacles. The proof of method is shown by using several graphs namely in terms of time, packet loss and also throughput
Clinical Experience with Insulin Detemir: Results from the Bangladesh Cohort of Global A 1 chieve Study
Abstract Objective: To present results from the Bangladesh cohort of the A 1 chieve study receiving insulin detemir (Levemir) ± oral anti diabetic drugs. Methods: Out of 1093 patients recruited from 49 sites in Bangladesh, 370 were initiated on insulin detemir (Levemir).Study visits were defined as baseline, interim (around 12 weeks from baseline) and final (around 24 weeks from baseline) visit. Results: Glycaemic control was poor in all the groups at baseline. In the entire cohort at 24 weeks, significant reductions from baseline were observed in mean HbA 1c (from 10.0 % to 7.2%, p<0.001), FPG (from 10.5 to 6.7 mmol/L, p<0.001) and PPPG (from 15.3 to 8.9 mmol/L, p<0.001) levels. Overall 45.5% of th
Expanding the diversity of mycobacteriophages: Insights into genome architecture and evolution
Mycobacteriophages are viruses that infect mycobacterial hosts such as Mycobacterium smegmatis and Mycobacterium tuberculosis. All mycobacteriophages characterized to date are dsDNA tailed phages, and have either siphoviral or myoviral morphotypes. However, their genetic diversity is considerable, and although sixty-two genomes have been sequenced and comparatively analyzed, these likely represent only a small portion of the diversity of the mycobacteriophage population at large. Here we report the isolation, sequencing and comparative genomic analysis of 18 new mycobacteriophages isolated from geographically distinct locations within the United States. Although no clear correlation between location and genome type can be discerned, these genomes expand our knowledge of mycobacteriophage diversity and enhance our understanding of the roles of mobile elements in viral evolution. Expansion of the number of mycobacteriophages grouped within Cluster A provides insights into the basis of immune specificity in these temperate phages, and we also describe a novel example of apparent immunity theft. The isolation and genomic analysis of bacteriophages by freshman college students provides an example of an authentic research experience for novice scientists. © 2011 Hatfull et al
Large expert-curated database for benchmarking document similarity detection in biomedical literature search
Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term FrequencyâInverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research
The structure and regulation of Cullin 2 based E3 ubiquitin ligases and their biological functions
Seasonal forecasting of Bangladesh summer monsoon rainfall using simple multiple regression model
Anomalous Winter Climate Conditions in the Pacific Rim during Recent El Nino Modoki and El Nino Events
Environment and air pollution: health services bequeath to grotesque menace
The objective of the study is to establish the link between air pollution, fossil fuel energy consumption, industrialization, alternative and nuclear energy, combustible renewable and wastes, urbanization, and resulting impact on health services in Malaysia. The study employed two-stage least square regression technique on the time series data from 1975 to 2012 to possibly minimize the problem of endogeniety in the health services model. The results in general show that air pollution and environmental indicators act as a strong contributor to influence Malaysian health services. Urbanization and nuclear energy consumption both significantly increases the life expectancy in Malaysia, while fertility rate decreases along with the increasing urbanization in a country. Fossil fuel energy consumption and industrialization both have an indirect relationship with the infant mortality rate, whereas, carbon dioxide emissions have a direct relationship with the sanitation facility in a country. The results conclude that balancing the air pollution, environment, and health services needs strong policy vistas on the end of the government officials.</p