Flow-Aware Elephant Flow Detection for Software-Defined Networks

Software-defined networking (SDN) separates the network control plane from the packet forwarding plane, which provides comprehensive network-state visibility for better network management and resilience. Traffic classification, particularly for elephant flow detection, can lead to improved flow control and resource provisioning in SDN networks. Existing elephant flow detection techniques use pre-set thresholds that cannot scale with the changes in the traffic concept and distribution. This paper proposes a flow-aware elephant flow detection applied to SDN. The proposed technique employs two classifiers, each respectively on SDN switches and controller, to achieve accurate elephant flow detection efficiently. Moreover, this technique allows sharing the elephant flow classification tasks between the controller and switches. Hence, most mice flows can be filtered in the switches, thus avoiding the need to send large numbers of classification requests and signaling messages to the controller. Experimental findings reveal that the proposed technique outperforms contemporary methods in terms of the running time, accuracy, F-measure, and recall

Spontaneous Expulsion of a Biliary Stent via the abdominal wall: A rare complication: Case Report

We report a rare complication of a biliary stent inserted via endoscopic retrograde cholangio-pancreatography (ERCP) for benign biliary disease in a 60 years-old female presented with abdominal pain and a tender left iliac fossa (LIF) mass. She had change of the colour of the skin over the hypogastric region. Crepitus was felt in the subcutaneous tissue. Surgical drainage of the abscess was undertaken. A black, 14-cm biliary stent was found in the centre of the necrotic tissue. The patient, thereafter, made an uneventful recovery and the LIF mass disappeared. The wound was closed with secondary sutures about three weeks later, and complete healing was achieved thereafter. Here we discuss this rare complication. Keywords: Biliary stent migration, colonic perforation, abdominal mass, large bowel obstruction, abdominal wall abscess, ERCP complication. Sudan Journal of Medical Sciences Vol. 3 (3) 2008: pp. 255-25

Phytic acid: How far have we come?

Phytic acid is a major storage form of phosphorous. Obvious reasons are there to favor its reduced concentration in organisms. However, certain justifications can also be settled, in order to support its increased natural concentration. In both cases, there are questions to be answered to favor one side while alleviating the harm of neglecting the other. This article reviews our current state of understanding of phytic acid - focusing on the topics of current and future interests in the field

Determination of some significant batch culture conditions affecting acetyl-xylan esterase production by Penicillium notatum NRRL-1249

<p>Abstract</p> <p>Background</p> <p>Acetyl-xylan esterase (AXE, <it>EC 3.1.1.72</it>) hydrolyses acetate group from the linear chain of xylopyranose residues bound by β-1,4-linkage. The enzyme finds commercial applications in bio-bleaching of wood pulp, treating animal feed to increase digestibility, processing food to increase clarification and converting lignocellulosics to feedstock and fuel. In the present study, we report on the production of an extracellular AXE from <it>Penicillium notatum </it>NRRL-1249 by solid state fermentation (SSF).</p> <p>Results</p> <p>Wheat bran at a level of 10 g (with 4 cm bed height) was optimized as the basal substrate for AXE production. An increase in enzyme activity was observed when 7.5 ml of mineral salt solution (MSS) containing 0.1% KH₂PO₄, 0.05% KCl, 0.05% MgSO₄.7H₂O, 0.3% NaNO₃, 0.001% FeSO₄.2H₂O and 0.1% (v/w) Tween-80 as an initial moisture content was used. Various nitrogen sources including ammonium sulphate, urea, peptone and yeast extract were compared for enzyme production. Maximal enzyme activity of 760 U/g was accomplished which was found to be highly significant (p ≤ 0.05). A noticeable enhancement in enzyme activity was observed when the process parameters including incubation period (48 h), initial pH (5), 0.2% (w/w) urea as nitrogen source and 0.5% (v/w) Tween-80 as a stimulator were further optimized using a 2-factorial Plackett-Burman design.</p> <p>Conclusion</p> <p>From the results it is clear that an overall improvement of more than 35% in terms of net enzyme activity was achieved compared to previously reported studies. This is perhaps the first report dealing with the use of <it>P. notatum </it>for AXE production under batch culture SSF. The Plackett-Burman model terms were found highly significant (<it>HS</it>), suggesting the potential commercial utility of the culture used (df = 3, LSD = 0.126).</p

Simulation of Levels of Noise Generated by Local Grinding Machnies Within the Community (A Case Study of Kaduna Metropolis, Nigeria)

Abstract Levels of noise generated from grinding mach ines were measured. Noise levels as high as 116d B was obtained. These levels of noise can be stressful that can result to fatigue. It is capable of causing temporary and permanent deaf. No ise spectra generated from grinding machines are mixture of lo w and high frequencies. Low and high frequencies noise can have negative effects on memory. The levels of noise generated from these machines are very high and are above the international standard value. Critical investigations showed that some of these machines are old enough to be replaced, lack adequate maintenance and were poorly installed, thereby gave rooms for vibrations. Noise generated from these machines can result to quarrel in the neighbourhood since they are located within the co mmun it

Shape invariant potential formalism for photon-added coherent state construction

An algebro-operator approach, called shape invariant potential method, of constructing generalized coherent states for photon-added particle system is presented. Illustration is given on Poschl-Teller potential

Comparative computational study of mechanical behavior in self-expanding femoropopliteal stents

The use of the stent to treat peripheral artery disease (PAD) is increased and the proportion of failures also increases. The femoropopliteal artery (FPA) experiences a high deformation ratio compared to the cardiovascular artery due to limp flexion and daily activities that could lead to stent failure, as well as increasing the number of observed mortality and morbidity. In the present work, two of the common PAD stent design models represented as STENT I and STENT II were analyzed by using of finite element method (FEM) to simulate the most mechanical loading modes that could occur in FPA, such as axial tension and compression, torsion, three-point bending and radial compression to give a good understanding of deformation that affected stent inside the in-vivo. The gradual force load was used to simulate all modes, the force values are 0.25 N, 0.5 N, 1.5 N, 2.5 N, 3.5 N and 5.5 N until the stent models obtain the yield-point. The comparison of stent models (STENT I, STENT II) was performed in terms of graphs of total deformation, force-stress and stress-strain for all test modes. The similarity ratio of the total deformation in axial tension and the compression mode for STENT I and STENT II was 17% and that may indicate that STENT I obtained a high deformation value instead of STENT II, while, the torsion similarity ratio was 86% which could show a good agreement in this mode, as well as the similarity ratio, was 78% of the total three-point bending deformation and the value of the similarity ratio in the radial compression mode was 23%. Still unclear what is the clinical mode of mechanical deformation that is more important than others with changing the length of the lesion and stent diameter, and the fatigue life test provides a better understanding of the mechanical tests that must be sought

On Hilbert-Schmidt operator formulation of noncommutative quantum mechanics

This work gives value to the importance of Hilbert-Schmidt operators in the formulation of a noncommutative quantum theory. A system of charged particle in a constant magnetic field is investigated in this framework

Antenatal myomectomy: is it safe?

Myomectomy is rarely performed in pregnancy due to risk of miscarriage or pregnancy loss, bleeding and possible hysterectomy. Myomectomy is mainly reserved for unavoidable indications such as rapidly growing fibroid or severe pain with possiblity of red degeneration for which medical treatment failed. However, good outcome had been reported in selective second trimester myomectomies