7 research outputs found
A Geologic Play Book for Utica Shale Appalachian Basin Exploration
This “Geologic Play Book for Utica Shale Appalachian Basin Exploration” (hereafter referred to as the “Utica Shale Play Book Study” or simply “Study”) represents the results of a two-year research effort by workers in five different states with the financial support of fifteen oil and gas industry partners. The Study was made possible through a coordinated effort between the Appalachian Basin Oil & Natural Gas Research Consortium (AONGRC) and the West Virginia University Shale Research, Education, Policy and Economic Development Center
Head‐Mounted Devices for Noninvasive Cancer Imaging and Intraoperative Image‐Guided Surgery
Purification and characterization of the cytosolic NADP+-dependent malic enzyme from human breast cancer cell line
Differential evolution algorithm based photonic structure design: Numerical and experimental verification of subwavelength ? /5 focusing of light
Photonic structure designs based on optimization algorithms provide superior properties compared to those using intuition-basedapproaches. In the present study, we numerically and experimentally demonstrate subwavelength focusing of light using wavelength scale absorption-free dielectric scattering objects embedded in an air background. An optimization algorithm based on differential evolution integrated into the finite-difference time-domain method was applied to determine the locations of each circular dielectric object with a constant radius and refractive index. The multiobjective cost function defined inside the algorithm ensures strong focusing of light with low intensity side lobes. The temporal and spectral responses of the designed compact photonic structureprovided a beam spot size in air with a full width at half maximum value of 0.19?, where ? is the wavelength of light. The experiments were carried out in the microwave region to verify numerical findings, and very good agreement between the two approaches was found. The subwavelength light focusing is associated with a strong interference effect due to nonuniformly arranged scatterers and an irregular index gradient. Improving the focusing capability of optical elements by surpassing the diffraction limit of light is of paramount importance in optical imaging, lithography, data storage, and strong light-matter interaction. © The Author(s) 2016