4,030 research outputs found
Experimental validation of some basic assumptions used in physically based soil
In spring 2009, four rill experiments were accomplished on a fallow land. Most external factors as well as discharge quantity (9 L min-1) were held constant or at least in the same range. Following most process based soil erosion models, detachment or runoff values should therefore be similar, but the experimental results show clear differences in sediment concentration, runoff and other measured and calculated values. This fact underlines the problems of process based models: concerning rill erosion, different processes take part and the process described by the models is only responsible for a part of the eroded material
ANOMALY DETECTION OF EMS HARDWIRED INFRASTRUCTURE USING SUPERVISED AND UNSUPERVISED ARTIFICIAL INTELLIGENCE MACHINE LEARNING
The microgrid currently deployed at Marine Corps Air Station (MCAS) Miramar, California began operations in 2021. It is unique in its efforts to leverage a Verizon, fifth generation technology (5G), non-standalone communications network to provide connectivity between distributed energy resources and the MCAS energy management system (EMS). With this new technology comes additional risks in the form of cyber attacks. Therefore, novel approaches to combat this threat are necessary to protect vital energy assets. In this thesis, we discuss the development of anomalous traffic detection models that use an unsupervised machine learning autoencoder trained on benign data sets captured from an AT&T 5G cellular tower at the Naval Postgraduate School Sea Land Air Military Research facility and Raytheon hardwired Modbus network at the EMS. We created synthetic anomalies for each data set to test our autoencoder and assess its effectiveness at classifying these packets as anomalous or benign. F-score, accuracy, precision, and recall were used as performance metrics. Through experiments conducted with Python and TensorFlow, we demonstrate the autoencoder models can successfully be trained and tested using benign network data using carefully crafted synthetic anomalies. This research establishes a baseline of research for an autoencoder to be used as an effective intrusion detection system to demonstrate the utility and operability of unsupervised machine learning for use in a microgrid.Distribution Statement A. Approved for public release: Distribution is unlimited.Lieutenant Commander, United States NavyONR, Arlington, VA 2221
The relationship between insulin binding, insulin activation of insulin-receptor tyrosine kinase, and insulin stimulation of glucose uptake in isolated rat adipocytes
We have studied the relationship between insulin activation of insulin-receptor kinase and insulin stimulation of glucose uptake in isolated rat adipocytes. Glucose uptake was half-maximally or maximally stimulated, respectively, when only 4% or 14% of the maximal kinase activity had been reached. To investigate this relationship also under conditions where the insulin effect on activation of receptor kinase was decreased, the adipocytes were exposed to 10 microM-isoprenaline alone or with 5 micrograms of adenosine deaminase/ml. An approx. 30% (isoprenaline) or approx. 50% (isoprenaline + adenosine deaminase) decrease in the insulin effect on receptor kinase activity was found at insulin concentrations between 0.4 and 20 ng/ml, and this could not be explained by decreased insulin binding. The decreased insulin-effect on kinase activity was closely correlated with a loss of insulin-sensitivity of glucose uptake. Moreover, our data indicate that the relation between receptor kinase activity and glucose uptake (expressed as percentage of maximal uptake) remained unchanged. The following conclusions were drawn. (1) If activation of receptor kinase stimulates glucose uptake, only 14% of the maximal kinase activity is sufficient for maximal stimulation. (2) Isoprenaline decreases the coupling efficiency between insulin binding and receptor-kinase activation, this being accompanied by a corresponding decrease in sensitivity of glucose uptake. (3) Our data indicate that the signalling for glucose uptake is closely related to receptor-kinase activity, even when the coupling efficiency between insulin binding and kinase activation is altered. They thus support the hypothesis that receptor-kinase activity reflects the signal which originates from the receptor and which is transduced to the glucose-transport system
Quantum scissors: teleportation of single-mode optical states by means of a nonlocal single photon
We employ the quantum state of a single photon entangled with the vacuum
(|1,0>-|0,1>), generated by a photon incident upon a symmetric beam splitter,
to teleport single-mode quantum states of light by means of the Bennett
protocol. Teleportation of coherent states results in truncation of their Fock
expansion to the first two terms. We analyze the teleported ensembles by means
of homodyne tomography and obtain fidelities of up to 99 per cent for low
source state amplitudes. This work is an experimental realization of the
quantum scissors device proposed by Pegg, Phillips and Barnett (Phys. Rev.
Lett. 81, 1604 (1998)
Teaching a Credit Course: What You Don’t Know May Surprise You!
An inside look at the realities and differences between teaching a one-shot B.I. lecture and teaching a library course for credit: time, student relations, administrivia, rewards, etc
The Wendelstein Calar Alto Pixellensing Project (WeCAPP): the M31 Nova catalogue
We present light curves from the novae detected in the long-term, M31
monitoring WeCAPP project. The goal of WeCAPP is to constrain the compact dark
matter fraction of the M31 halo with microlensing observations. As a by product
we have detected 91 novae benefiting from the high cadence and highly sensitive
difference imaging technique required for pixellensing. We thus can now present
the largest CCD and optical filters based nova light curve sample up-to-date
towards M31. We also obtained thorough coverage of the light curve before and
after the eruption thanks to the long-term monitoring. We apply the nova
taxonomy proposed by Strope et al. (2010) to our nova candidates and found 29
S-class novae, 10 C-class novae, 2 O-class novae and 1 J-class nova. We have
investigated the universal decline law advocated by Hachichu and Kato (2006) on
the S-class novae. In addition, we correlated our catalogue with the literature
and found 4 potential recurrent novae. Part of our catalogue has been used to
search for optical counter-parts of the super soft X-ray sources detected in
M31 (Pietsch et al. 2005). Optical surveys like WeCAPP, and coordinated with
multi-wavelength observation, will continue to shed light on the underlying
physical mechanism of novae in the future.Comment: 15 pages, 15 figures, 7 tables, A&A accepted for publication. The
appendix is stored in the Data Conservanc
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