10,265 research outputs found
Stroke volume estimation by thoracocardiography is better when glottis is closed
Thoracocardiography approach pretends to non-invasively monitor stroke volume
by inductive plethysmographic recording of ventricular volume curves by a
transducer placed on the chest. The purpose of this study was to investigate
the potential of thoracocardiography to estimate stroke volumes while apnea
with open glottis. We hypothesized that, when glottis is open, stroke volumes
would be better estimated if airways flow curves were taken into account
An Introduction To Compressive Sampling [A sensing/sampling paradigm that goes against the common knowledge in data acquisition]
This article surveys the theory of compressive sampling, also known as compressed sensing or CS, a novel sensing/sampling paradigm that goes against the common wisdom in data acquisition. CS theory asserts that one can recover certain signals and images from far fewer samples or measurements than traditional methods use. To make this possible, CS relies on two principles: sparsity, which pertains to the signals of interest, and incoherence, which pertains to the sensing modality.
Our intent in this article is to overview the basic CS theory that emerged in the works [1]–[3], present the key mathematical ideas underlying this theory, and survey a couple of important results in the field. Our goal is to explain CS as plainly as possible, and so our article is mainly of a tutorial nature. One of the charms of this theory is that it draws from various subdisciplines within the applied mathematical sciences, most notably probability theory. In this review, we have decided to highlight this aspect and especially the fact that randomness can — perhaps surprisingly — lead to very effective sensing mechanisms. We will also discuss significant implications, explain why CS is a concrete protocol for sensing and compressing data simultaneously (thus the name), and conclude our tour by reviewing important applications
The consolidation process of the EU regulatory framework on nanotechnologies: within and beyond the EU case-by-case approach
The field of nanotechnologies has been the subject of a process of wide-ranging regulation,
which covers two different trends. From the 2000s the European Commission and
Parliament agreed on a type of adaptive, experimental and flexible approach, which had its
apex with the Commission code of conduct on responsible nano-research developed
through a set of consultations. In 2009 this initial agreement subsequently broke down and
the EU started to develop a set of regulatory initiatives of a sectoral nature in several fields
(cosmetics, food, biocides). Thus, the current arrangement of governance in the field of
nanotechnologies appears to be a hybrid, which mixes forms belonging to the new
governance method (consultations, self-regulation, agency, comitology committees,
networking), working like a lung in the framework of EU policy, with more traditional tools
belonging to the classic governance method (regulations, directives). This model of
governance based on a case-by-case approach runs the risk of lacking coherence since it is
exposed to sudden changes of direction when risks emerge and it has a weak anticipatory
dimension due to both its excessive dependency on data collection and its insufficient use of
upstream criteria, such as human rights, which should be used earlier, to allow anticipated
intervention with a less intense use of hard law solutions
Analysis of Effects of BGP Black Hole Routing on a Network like the NIPRNET
The Department of Defense (DoD) relies heavily on the Non-secure Internet Protocol Router Network (NIPRNET) to exchange information freely between departments, services, bases, posts, and ships. The NIPRNET is vulnerable to various attacks, to include physical and cyber attacks. One of the most frequently used cyber attacks by criminally motivated hackers is a Distributed Denial of Service (DDoS) attack. DDoS attacks can be used to exhaust network bandwidth and router processing capabilities, and as a leveraging tool for extortion. Border Gateway Protocol (BGP) black hole routing is a responsive defensive network technique for mitigating DDoS attacks. BGP black hole routing directs traffic destined to an Internet address under attack to a null address, essentially stopping the DDoS attack by dropping all traffic to the targeted system. This research examines the ability of BGP black hole routing to effectively defend a network like the NIPRNET from a DDoS attack, as well as examining two different techniques for triggering BGP black hole routing during a DDoS attack. This thesis presents experiments with three different DDoS attack scenarios to determine the effectiveness of BGP black hole routing. Remote-triggered black hole routing is then compared against customer-triggered black hole routing to examine how well each technique reacts under a DDoS attack. The results from this study show BGP black hole routing to be highly successful. It also shows that remote-triggered black hole routing is much more effective than customer-triggered
Parallel Processing of Large Graphs
More and more large data collections are gathered worldwide in various IT
systems. Many of them possess the networked nature and need to be processed and
analysed as graph structures. Due to their size they require very often usage
of parallel paradigm for efficient computation. Three parallel techniques have
been compared in the paper: MapReduce, its map-side join extension and Bulk
Synchronous Parallel (BSP). They are implemented for two different graph
problems: calculation of single source shortest paths (SSSP) and collective
classification of graph nodes by means of relational influence propagation
(RIP). The methods and algorithms are applied to several network datasets
differing in size and structural profile, originating from three domains:
telecommunication, multimedia and microblog. The results revealed that
iterative graph processing with the BSP implementation always and
significantly, even up to 10 times outperforms MapReduce, especially for
algorithms with many iterations and sparse communication. Also MapReduce
extension based on map-side join usually noticeably presents better efficiency,
although not as much as BSP. Nevertheless, MapReduce still remains the good
alternative for enormous networks, whose data structures do not fit in local
memories.Comment: Preprint submitted to Future Generation Computer System
Analisis Unjuk Kerja Ripv2 dan Eigrp dalam Dynamic Routing Protocol
Jaringan komunikasi komputer didukung oleh protokol routing untuk mengirimkan paket data. Ada berbagai jenis protokol routing yang banyak digunakan, diantaranya Routing Information Protocol version 2 (RIPv2) dan Enhanced Interior Gateway Routing Protocol (EIGRP) yang masuk ke dalam dynamic routing protocol. RIPv2 menggunakan protokol distance vector, sedangkan EIGRP dikategorikan pada protokol hybrid. RIPv2 menggunakan request message untuk membangun hubungan dengan router tetangga, sedangkan EIGRP menggunakan hello packet.Tulisan ini membandingkan kedua protokol tersebut dari aspek daftar tabel routing, informasi mengenai protokol routing, kemampuan menghasilkan tabel topologi, kemampuan mengenali router tetangga (tabel neighbor), melihat konektivitas jaringan, dan memeriksa jalur yang dilewati oleh paket data. Hasilnya adalah EIGRP memiliki konvergensi yang lebih baik dibandingkan RIPv2. RIPv2 melakukan update tabel routing ke seluruh router, sedangkan EIGRP hanya pada router yang terkena dampak langsung dari Perubahan topologi jaringan. EIGRP mampu menghasilkan tabel topologi dan tabel neighbor, sedangkan RIPv2 tidak
Interaction of RNA-binding protein HuR and miR-466i regulates GM-CSF expression.
Granulocyte-macrophage colony-stimulating factor (GM-CSF) produced by T helper 17 (Th17) cells plays an essential role in autoimmune diseases. Transcriptional regulation of Th17 cell differentiation has been extensively studied, but post-transcriptional regulation of Th17 cell differentiation has remained less well characterized. The RNA-binding protein HuR functions to promote the stability of target mRNAs via binding the AU-rich elements of the 3\u27 untranslated region (3\u27UTR) of numerous pro-inflammatory cytokines including IL-4, IL-13, IL-17 and TNF-α. However, whether HuR regulates GM-CSF expression in Th17 cells has not been fully investigated. Here we showed that HuR conditional knockout (KO) Th17 cells have decreased GM-CSF mRNA in comparison with wild-type (WT) Th17 cells, and that HuR binds directly to GM-CSF mRNA 3\u27UTR. Interestingly, HuR deficiency increased the levels of certain microRNA expression in Th17 cells; for example, miR-466i functioned to mediate GM-CSF and IL-17 mRNA decay, which was confirmed by in vitro luciferase assay. Furthermore, we found that HuR promoted Mxi1 expression to inhibit certain miRNA expression. Taken together, these findings indicate that interaction of HuR and miR-466i orchestrates GM-CSF expression in Th17 cells
Performance Analysis of Network Emulator Based on the Use Of Resources in Virtual Laboratory
A network emulator is a software in its environment mimicking the functions and habits of the original network. Problems often encountered in doing research on computer networks is a problem of design and trial scenarios that require software and hardware enough to implement such a network scenario similar to a real scenario. Using virtual machine technology is expected to solve the problem. Netkit supports experiments with various network technologies and can support other technologies necessary for certain network experiments. This study uses a network emulator with netkit, where it is freely available and built based on Linux User Mode. Netkit allows users to experiment with complex computer network scenarios that can be easily implemented using linux. The experimental research is done by making the design first. The design is used to implement the routing process, to connect 4 different network addresses. On the Netkit implementation of the design, it is implemented by creating a virtual routing lab based on data from computer network topologies. The virtual laboratory implementation of this research routing is based on a network topology scenario. The results of these virtual routing lab experiments, the routing process runs well on the network based on predetermined test scenarios, with the occurrence of connections between different network addresses..In the end the virtual routing lab implementation works well, with performance analysis results from the netkit emulator on the use of computer resources showing Usage CPU usage of 0% and Memory Usage averaging 20942.8k test time for 12 minutes. The results of this trial is very helpful for administrators before the implementation on the real networ
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