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MarsWRF, the general circulation model of Mars, is one of the most commonly used models to study the dust cycle in the Martian atmosphere. It has been widely used to study the mechanisms of dust storms and their effects on the Martian atmosphere. To better understand the ability of MarsWRF to simulate the dust cycle on Mars, this study assesses the current dust lifting schemes in the model, specifically the convective lifting and wind stress schemes. It is found that, by tuning lifting efficiency, the model with the convective lifting scheme can generally reproduce the seasonal variation of the mid-level atmospheric temperature (T15) but cannot reproduce the observed spatial distribution of dust devils, which exhibits non-homogeneous (uniform) distribution in the northern (southern) hemisphere. The model with the wind stress lifting scheme can generally capture the observed magnitude of T15 and column dust optical depth (CDOD) with properly tuned lifting efficiency and threshold drag velocity. There is a discrepancy in the assessment of modeling seasonal variations of dust with T15 and CDOD, which may be partly due to the observational uncertainties related to T15 and CDOD and the empirical modeling methods of Martian dust optical properties and radiative effect. For the spatial distribution of dust, there are significant simulation biases regardless of the tuning, which may be caused by the biases in the dust lifting process and large-scale atmospheric circulation. The analysis highlights that dust lifting schemes need further improvement to better represent the dust cycle and their impacts on Mars.

In this study, the optical properties of a meta-GMR consisting of a metasurface stacked on a planar dielectric slab waveguide were theoretically investigated. Two different metasurfaces, namely chiral split-ring resonator dimer arrays with/without a rod-shaped antenna, were investigated and compared. Conventional GMR filters utilize gratings to couple the free-space electromagnetic field to the waveguide. The highly dispersive nature of grating leads to low angular tolerance. Here, the grating is replaced by metasurfaces. The metasurface unit cell can be regarded as a polarizable dipole that couples the free-space electromagnetic field to the waveguide and decouples the waveguide mode to the radiation modes. Based on the localized nature of the resonant metasurfaces, the metasurface/GMR hybrid mode exhibits a superior angular tolerance as compared with a conventional GMR filter. This study can open a new avenue to tailor the optical properties of GMR-based devices.

In this study, silicon oxynitride (SiOxNy) films and three-paired organosilicon/SiOxNy multilayered structures prepared by the plasma-enhanced chemical vapor deposition were respectively deposited onto the polyethylene terephthalate and silicon substrate with overcut and undercut patterned photoresist to mimic the packaging of the patterned organic light emitting diodes (OLEDs) and surface contaminants. The step coverage at the bottom and sidewall surface was conducted from the cross-sectional scanning electron microscopy observations. A methodology for investigating the position-dependent coverage at the concave region of the sidewall surface on the undercut patterns was developed. The increase in the water vapor transmission when these barrier structures were deposited onto polyethylene terephthalate substrate was linked to the decrease in their coverage at the sidewall surface, which was ascribed to the reduction in the diffusion path for water vapor permeation. It also was demonstrated that the degradation in the barrier property was significant as those structures coated onto the undercut patterns originating from the precursors hardly arrived at the concave region. However, although the film growth at the concave region of the sidewall surface was limited, paired organosilicon/SiOxNy structures still showed a superior barrier property to that of single SiOxNy film as the appearance of the organosilicon film in the paired structure was favorable to prolonging the diffusion length for water vapor permeation. The investigation into the barrier structures coated onto the patterned surface was beneficial for better understanding the package reliability on the patterned OLED devices.

The Genealogical Evolution Model (GEM) presented here is an efficient logical model used to track dynamic evolution of mesoscale eddies in the ocean. It can distinguish between different dynamic processes (e.g., merging and splitting) within a dynamic evolution pattern, which is difficult to accomplish using other tracking methods. To this end, the GEM first uses a two-dimensional (2-D) similarity vector (i.e., a pair of ratios of overlap area between two eddies to the area of each eddy) rather than a scalar to measure the similarity between eddies, which effectively solves the “missing eddy” problem (temporarily lost eddy in tracking). Second, for tracking when an eddy splits, the GEM uses both “parent” (the original eddy) and “child” (eddy split from parent) and the dynamic processes are described as the birth and death of different generations. Additionally, a new look-ahead approach with selection rules effectively simplifies computation and recording. All of the computational steps are linear and do not include iteration. Given the pixel number of the target region L, the maximum number of eddies M, the number N of look-ahead time steps, and the total number of time steps T, the total computer time is O(LM(N + 1)T). The tracking of each eddy is very smooth because we require that the snapshots of each eddy on adjacent days overlap one another. Although eddy splitting or merging is ubiquitous in the ocean, they have different geographic distributions in the North Pacific Ocean. Both the merging and splitting rates of the eddies are high, especially at the western boundary, in currents and in “eddy deserts”. The GEM is useful not only for satellite-based observational data, but also for numerical simulation outputs. It is potentially useful for studying dynamic processes in other related fields, e.g., the dynamics of cyclones in meteorology.

Interest in developing a rapid and robust DNA sequencing platform has surged over the past decade. Various next-/third-generation sequencing mechanisms have been employed to replace the traditional Sanger sequencing method. In sequencing by synthesis, a signal is monitored by a scanning charge-coupled device (CCD) to identify thousands to millions of incorporated dNTPs with distinctive fluorophores on a chip. Because one reaction site usually occupies dozens of pixels on a CCD detector, a bottleneck related to the bandwidth of CCD imaging limits the throughputs of the sequencing performance and causes trade-offs among speed, accuracy, read length, and the numbers of reaction sites in parallel. Thus, current research aims to align one reaction site to a few pixels by directly stacking nanophotonic layers onto a CMOS detector to minimize the size of the sequencing platforms and accelerate the processing procedures. This article reports a custom integrated optoelectronic device based on a triple-junction photodiode (TPD) CMOS sensor in conjunction with NPL integration for real-time illumination and detection of fluorescent molecules.

Fluorescent biosensors have been widely used in biomedical applications. To amplify the intensity of fluorescence signals, this study developed a novel structure for an evanescent wave fiber-optic biosensor by using a Fabry-Perot resonator structure. An excitation light was coupled into the optical fiber through a laser-drilled hole on the proximal end of the resonator. After entering the resonator, the excitation light was reflected back and forth inside the resonator, thereby amplifying the intensity of the light in the fiber. Subsequently, the light was used to excite the fluorescent molecules in the reactive region of the sensor. The experimental results showed that the biosensor signal was amplified eight-fold when the resonator reflector was formed using a 92% reflective coating. Furthermore, in a simulation, the biosensor signal could be amplified 20-fold by using a 99% reflector.

In this study, a polarization-control setup for intensity-resolved guided mode resonance sensors is proposed and demonstrated experimentally. The experimental results are in good agreement with the simulation data based on rigorous coupled wave approach calculations. The proposed intensity-resolved measurement setup transfers polarization ellipses, which are produced from guided mode resonance to a linear polarization state under a buffer solution condition, and then suppresses the signals to dark using a polarization-control set. Hence, any changes in the refractive index results in an increase in the intensity signals. Furthermore, no wavelength-resolved or angular-resolved measurement is needed in this scheme. According to the experimental results, a wide linear detection range of 0.014 refractive index units is achieved and the limit of detection is 1.62E-4 RIU.

A modified waveguide model for predicting the sensitivity of surface-relief guided mode resonance (GMR) biosensors is presented. The proposed model is a convenient and fast calculation method compared to the current optical simulation tools such as the rigorous couple wave analysis (RCWA). A systematic and theoretical discussion of the GMR geometric structure and sensitivity of the modified model for biosensing is also presented. For a given GMR material, the theoretical maximum sensitivity can be achieved by choosing the proper geometric structure from the model simulations. A comparison of the GMR biosensor sensitivity respectively calculated by the model and the RCWA method shows good agreement. Finally, a suspending GMR structure with a 4.5-fold increase in sensitivity compared to the traditional surface-relief GMR is proposed.

In this paper, the design of low-loss tapered waveguides by applying photonic-crystal-based microlenses is presented. The microlenses are realized by using two-dimensional photonic crystal (PhC) structures with a hexagonal periodic lattice of air-holes. In order to make the PhC structures behave as homogeneous and isotropic microlenses, the PhC structures are designed to operate in the low-frequency domain with light wavelength sufficiently larger than the PhC lattice constant. The effective indices of the PhC are calculated and the structures are properly arranged in microlenslike shapes. By monolithically integrating the effective microlenses in the tapered area between the two optical waveguides with different core dimensions, the wavefront of the eigenmode can be coupled from the larger core to the smaller core effectively and also the radiation loss in the tapered area between the two connected optical waveguides can be effectively suppressed. The results show that the PhC-based microlens in the telescopic structure can serve as an optical element in the tapered waveguide with the advantages of low loss, high efficiency and compactness.

In this study, a metal assisted guide mode resonance device for bioanalytical applications is proposed. The particular spectrum inversion property and its resonance mechanism are discussed. The metal assisted guided mode resonance eliminates evanescent wave distributed in substrate and provides a strongly asymmetric modal profile; the evanescent wave is one fold enhanced in top medium. The intrinsic bulk sensitivity achieves 337.5 in a fundamental TM mode resonating at 800nm with 1st diffraction angle.

Recent developments in aptamers have led to their widespread use in analytical and diagnostic applications, particularly for biosensing. Previous studies have combined aptamers as ligands with various sensors for numerous applications. However, merging the aptamer developments with guided mode resonance (GMR) devices has not been attempted. This study reports an aptasensor based home built GMR device. The 29-mer thrombin aptamer was immobilized on the surface of a GMR device as a recognizing ligand for thrombin detection. The sensitivity reported in this first trial study is 0.04 nm/μM for thrombin detection in the concentration range from 0.25 to 1 μM and the limit of detection (LOD) is 0.19 μM. Furthermore, the binding affinity constant (Ka) measured is in the range of 10(6) M(-1). The investigation has demonstrated that such a GMR aptasensor has the required sensitivity for the real time, label-free, in situ detection of thrombin and provides kinetic information related to the binding.

FEA is a key product development tool, and remote FEA (Finite Element Analysis) services via internet are an effective and economical way to popularizing FEA technology for different-sized manufacturing enterprises. For FEA Grid portal, modeling technologies of FEA grid services and Grid information management structure are presented in this paper. For modeling technologies of FEA grid service, workflow of FEA automatic analysis job, models of FEA grid service and data management are described. WSRF (Web Service Resource Framework) based Grid information management structure is presented, and an application scenario of remote FEA service is demonstrated by taking FEA parametric optimization job as example. The research results in this paper provide the basis for developing FEA Grid portal.

In this paper, the polarization dependent optical properties of GaN surface relief grating are investigated using dark field angle-resolved photoluminescence (ARPL) spectrometer. The light extraction efficiency with the transverse electric (TE) and transverse magnetic (TM) pumping source represents a TE polarized dominated property. It is found that the TE and TM waveguide modes cannot be simultaneously coupled out, therefore light extraction is polarization dependent. The ARPL spectrum also reveals that the extraction efficiency is relatively high as the dispersion line of the waveguide mode is coincident with the folded free-photon dispersion of the 1D GaN grating.

In this paper, a metal layer assisted guide mode resonance (MaGMR) device with high sensitivity is proposed for bioanalytical applications and its functioning is experimentally proved. We find that the reflection spectra present a unique inversed response. The resonance mechanism is also discussed. Numerical calculation results indicate that the high sensitivity performance of MaGMR comes from the strongly asymmetric resonance modal profile and low propagation angle inside the waveguide. There is a one-fold enhancement of the evanescent wave in the analytes region compared to typical GMR. According to the experimental results, the proposed MaGMR achieved a bulk sensitivity of 376.78 nm/RIU in fundamental TM mode resonating at 0.809 μm with the first diffraction angle. Experiment results show a 264.78% enhancement in the sensitivity compared to that of the typical GMR sensor in the same resonance conditions of TM mode.