Detection of Mines in Acoustic Images using Higher Order Spectral Features

A new pattern-recognition algorithm detects approximately 90% of the mines hidden in the Coastal Systems Station Sonar0, 1, and 3 databases of cluttered acoustic images, with about 10% false alarms. Similar to other approaches, the algorithm presented here includes processing the images with an adaptive Wiener filter (the degree of smoothing depends on the signal strength in a local neighborhood) to remove noise without destroying the structural information in the mine shapes, followed by a two-dimensional FIR filter designed to suppress noise and clutter, while enhancing the target signature. A double peak pattern is produced as the FIR filter passes over mine highlight and shadow regions. Although the location, size, and orientation of this pattern within a region of the image can vary, features derived from higher order spectra (HOS) are invariant to translation, rotation, and scaling, while capturing the spatial correlations of mine-like objects. Classification accuracy is improved by combining features based on geometrical properties of the filter output with features based on HOS. The highest accuracy is obtained by fusing classification based on bispectral features with classification based on trispectral features

Migration of Price Discovery With Constrained Futures Markets

This paper investigates the information content of futures option prices when the futures price is regulated while the futures option price itself is not. The New York Board of Trade provides the empirical setting for this type of dichotomy in regulation. Most commodity derivatives markets regulate prices of all derivatives on a particular commodity simultaneously. NYBOT has taken an almost unique position by imposing daily price limits on their futures contracts while leaving the options prices on these futures contracts unconstrained. The study takes a particular interest in the volatility and futures prices of the options-implied risk neutral density when the underlying futures contract is locked limit.option implied density; price limits

A Conversation With Steve Shagan

On the evening of November 11, Steve Shagan met with the film students at Columbia College. Shagan authored and produced Save the Tiger. The discussion was moderated by Anthony Loeb, chair of the Film Department. Photographer: Randy Donefrio. 23 pages.https://digitalcommons.colum.edu/conversations/1003/thumbnail.jp

A feasibility study in rearchitecting UML as a family of languages using a precise OO meta-modeling approach.

This report describes a feasibility study in rearchitecting UML. It develops a theory of precise OO meta-modeling in order to fulfil this task, and checks the feasibility of that theory by developing the meta-model of various aspects of UML

SUMOylation determines the voltage required to activate cardiac IKs channels.

IKs channels open in response to depolarization of the membrane voltage during the cardiac action potential, passing potassium ions outward to repolarize ventricular myocytes and end each beat. Here, we show that the voltage required to activate IKs channels depends on their covalent modification by small ubiquitin-like modifier (SUMO) proteins. IKs channels are comprised of four KCNQ1 pore-forming subunits, two KCNE1 accessory subunits, and up to four SUMOs, one on Lys424 of each KCNQ1 subunit. Each SUMO shifts the half-maximal activation voltage (V1/2) of IKs ∼ +8 mV, producing a maximal +34-mV shift in neonatal mouse cardiac myocytes or Chinese hamster ovary (CHO) cells expressing the mouse or human subunits. Unexpectedly, channels formed without KCNE1 carry at most two SUMOs despite having four available KCNQ1-Lys424 sites. SUMOylation of KCNQ1 is KCNE1 dependent and determines the native attributes of cardiac IKs in vivo

Antenatal size, early childhood growth, and asthma within a cohort created by data linkage

ACKNOWLEDGMENTSThe authors are grateful to colleagues in electronic Data Researchand Innovation Service and the Grampian Data Safe Haven for theirsupport. Also, the authors are grateful to Ms. Vladimira Vladimirovafor her input into the project.Peer reviewedPublisher PD