Cloud network monitoring data is dynamic and distributed. Signals to monitor the cloud can appear, disappear or change their importance and clarity over time. Machine learning (ML) models tuned to a given data set can therefore quickly become inadequate. A model might be highly accurate at one point in time but may lose its accuracy at a later time due to changes in input data and their features. Distributed learning with dynamic model selection is therefore often required. Under such selection, poorly performing models are retired or put on standby while new or standby models are brought in. In this paper, we propose such methodology for automatic ML model selection and tuning that automates the model build and selection and is competitive with existing methods. In particular, we create a Cloud DevOps architecture for autotuning and selection based on container orchestration and messaging between containers, and take advantage of a new autoscaling method to dynamically create and evaluate instantiations of ML algorithms. The proposed methodology and tool are demonstrated on cloud network security datasets.
As the industry prepares for the 1000x mobile data challenge and the resulting spectrum crunch that LTE networks are anticipating in the licensed spectrum, the extension of LTE to the unlicensed spectrum (LTE-U) has been proposed as a promising solution. However, this extension is challenged by the problem of coexistence with incumbent unlicensed systems, especially WiFi. Several LTE channel access mechanisms for enabling fair and friendly coexistence with WiFi have been proposed and evaluated. This paper further explores the design of LTE-U - WiFi coexistence mechanisms from the perspective of video streaming. Specifically, two channel access mechanisms are proposed that take into account the difference in the availability of the LTE licensed and unlicensed channels along with the structure of the encoded video file. The performance of the proposed access mechanisms are evaluated via simulations and shown to outperform the classical Listen Before Talk (LBT) channel access mechanism.
Biological movements provide inspiration to solve several real-world problems, resulting in the rise of several bio-inspired optimization techniques. However, to develop an efficient bio-inspired technique, it is necessary to first understand the underlying physical statistics and models. While most biological movements could be generalized as "random" at first glance, deeper empirical studies suggest that the movements in organisms follow a much more complex randomness than a simple Brownian particle movement. This paper first introduces the variations of randomness observed in biological walks and statistical models used to imitate them, and then proposes on a possible tangent of an ant colony inspired biased random walk that could help implement efficient searches in unknown environments.
The disproportionate collapse of world trade center in September 11, 2001 is a turning point to study and enhance robustness to prevent progressive collapse of structures. This research aims to study T-stub components of beam-to-column extended bolted end plate connections under quasistatic large displacements for improving robustness. For this purpose, experimental testing and advanced numerical finite element investigations are carried out. Calibration of material model and T-Stub macro components are based on tensile data. Parametric study is carried out for T-stub macro-components with End plate thickness ranging from 10mm to 18mm and distance between the bolts ranging from 90mm to 140mm. It is concluded that numerical models replicate exact behavior of experiment. Parametric study reveals decrease in yield strength and ultimate capacity with increasing distance between the bolts and/or reducing the end plate thickness.
The objective of this paper is to investigate the flexural behavior of square CFST beams experimentally using 4 point bending test. The experimental program conducted in this study consists of four CFST beams and two hollow steel beams. The parameters that are considered in the experimental program are the h/t ratio and the compressive strength of concrete. The results of the experimental program were carefully evaluated and showed that the moment capacity of square CFST beams significantly increase with the decrease of the h/t ratio. The results also showed that the compressive strength of concrete has no significance influence on the moment capacity of square CFST beams. Moreover, the moment capacity and the ductility of CFST beams has significantly improved compared with the hollow steel tubes
Retrofitting and repairing of deteriorating structures have been done using several techniques. Strengthening of Reinforced Concrete (RC) members in shear with externally bonded fiber reinforced polymer (FRP) plates and sheets has been commonly accepted. It has been observed that de-bonding of the CFRP laminate and other strengthening materials is the most common type of failure. To address this issue many anchorage systems and methods have been developed. In this paper the use of bore-epoxy anchorage (Boring) system has been investigated. A total of five shear deficient RC beams were strengthened with carbon (CFRP) plates using groove-epoxy anchorage with grooves of different widths. The concrete beams were tested under four points bending. The results showed that the groove-epoxy anchorage delayed the CFRP de-bonding and increased the shear capacity of the concrete beams up to 106 % compared to the control beam.
Epoxy and cement mortar adhesives are used to externally bond the GSM sheets to concrete prisms. This research presents experimental results that were conducted to monitor the bond strength between Galvanized Steel Mesh (GSM) sheets and concrete surfaces via mortar and epoxy adhesives. The GSM sheets bonded length was chosen to be 200 mm in length which represents 40% of the prism's length. Three-point bending tests are conducted on the tested specimens and load- deflection response is recorded along the with associated capacity and failure modes. Epoxy and cement mortar bonded specimens failed in cohesive and adhesive modes, respectively. The strengthened specimen bonded with cement mortar was 40% less effective as compared to that bonded with epoxy adhesives. The ductility and strength of the epoxy bonded specimen was significantly higher than the specimens bonded with cement mortar.
This paper aims to present an experimental program of three T-section RC beams externally strengthened in flexure with hybrid combinations of Aluminum Alloy (AA), Carbon Fiber reinforced Polymer (CFRP) and Galvanized Steel Mesh (GSM) laminates. Three T-beams with 2?12 longitudinal reinforcement were prepared, two of them were strengthened with hybrid laminates and the third one was used as control specimen. Flexure test was conducted on each of the three beams using four-point loading test setup until the failure of the specimens. All specimens failed in flexure and delamination was the controlling failure mode for all the strengthened specimens. Load carrying capacity of the strengthened specimens increased from 46% to 51% over the control specimen.
Liposomes are nano-sized particles capable of providing efficient and site-specific delivery of therapeutic anticancer drugs. Further improvement to these nanocarriers can be achieved by attaching receptor-specific ligands to the surface of the liposomes to enhance selective delivery to tumor cells and limit adverse off-target effects. Our research focuses on the synthesis of transferrin (TF)-poly-ethylene glycol (PEG)-liposomes encapsulated with the model drug calcein and studying the effects of low- frequency ultrasound, applied at different power densities, on calcein release.
Conventional treatment of cancer involves chemotherapy which leads to many adverse side effects in patients. To minimize these effects, drug delivery systems involving the use of liposomes as nanocarriers have been developed along with ligand-targeting and ultrasound as an external stimulus to ensure site-specific, and fast release of drugs. The proposed research aims to target breast and colorectal cancer cells by employing plasminogen-receptor mediated endocytosis. To achieve this, liposomes attached with plasminogen shall be synthesized and characterized using dynamic light scattering, as well as Stewart and Bicinchoninic assays. The drug release at high and low ultrasound frequencies shall be studied and then modeled.
