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We design a thermal homeostasis device that passively regulates temperature 20× better than regular semiconductor materials. The thermal emission changes by a factor of 10 as the material temperature crosses a phase transition.
High-stiffness optical traps are developed for dielectric and metallic particles by exploiting the strong confinement of light in slot-graphite photonic crystal. An optical sieve is realized using the difference in growth kinetics of different nanoparticles.
We show the first demonstration of all-dielectric near-field optical Brownian ratchets of 520 nm particles with a transport speed of ∼1 μm/s, 10–100 times greater than other optical ratchets.
We exploit the resonant enhancement of light in photonic crystal slabs to enhance selected optical properties. Enhancement of absorption and local field gradients result in applications to microscale heating and optical trapping, respectively.
Spacecraft autonomous navigation method based on remote sensing image is a novel method which has been put into practical use in recent year. However, with the restricted computation resource onboard, this method still needs to look for a better way to improve its speed to satisfy real-time requirement. According to the problem above, this paper proposed an alternate method to faster image registration...
Quantification of land surface evapotranspiration (ET) at daily or longer time scales is of great significance in agricultural ecosystem and hydrologic cycle. Temporal upscaling of instantaneous remote sensing-based ET to daily or longer time scales is generally only based on a single instantaneous estimate. A test is made to use two instantaneous ET estimates for the daily upscaling. The results...
This paper presents a complement analysis for the wavelet transform method for separating temperature and emissivity (WTTES) with different wavelets, wavelet levels and biased atmospheric downwelling radiance. According to the results, the WTTES algorithm is quite insensitive to the choice of the wavelet. By comparing the retrievals with different wavelet levels, a wavelet level of n=3 or n=4 is more...
Thin cirrus clouds can reduce land surface long-wave transmission and re-emit energy at a colder temperature and thus making it difficult to estimate downwelling surface longwave radiation (DSLR) from satellite data. In this study, a simulation database is established in terms of radiances observed at the top of the atmosphere (TOA), cloud optical thickness (COT), atmosphere water vapor content (WVC)...
This paper aims to extend the generalized split-window (GSW) algorithm in land surface temperature (LST) retrieval to atmospheres with air temperature inversion (ATI) near the Earth surface boundary. Simulation analysis shows that the influence of ATI on the LST retrieval of the GSW algorithm becomes larger when the ATI intensity increases. To further analyze the influence, all ATI atmospheric profiles...
Evapotranspiration (ET) is one of the most significant components in the water and heat transfer between land and atmosphere. This paper develops an improved constant evaporative fraction (EF) method through a theoretical derivation to improve the upscaling of remote sensing instantaneous latent heat flux (LE) to daily scale. Preliminary results show that our improved constant EF upscaling method...
Land surface temperature is an important driving force in the exchange of water, heat, and even CO2 at the surface-atmosphere interface in the desert regions. The rapid and continuous measurements of land surface temperature are meaningful to the ecological and environmental researches. A physically based single-frequency and double-polarization algorithm for retrieving land surface temperature is...
Directional anisotropy limits the application of land surface temperature (LST) and a simplified parametric model to effectively estimate directional brightness temperature (DBT) in the thermal infrared is critical. This study used a widely validated four-stream scattering by arbitrarily inclined leaves (4SAIL) model as a benchmark to evaluate the performance of the kernel bidirectional reflectance...
This paper proposes a resilient Time-to-Digital Converter (TDC) that lends itself to cell-based design automation. We adopt a shrinking-based architecture with a number of distinctive techniques. First of all, a specialized on-chip re-calibration scheme is developed so that the real-time transfer function of the TDC in silicon (which maps an input pulse-width to its corresponding output code) can...
In order to recognize complicated PRI modulation modes, a classify algorithm based on auto-correlation and normalization is proposed. The mathematical model of four PRI modulation modes is given firstly. On the basis of making auto-correlation and normalization to four kinds of PRI modulation modes, it defines three characteristic quantities: density of peak value, intension of monotone and energy...
Location based service relies on precise outdoor and indoor positioning technologies. Intuitively, indoor positioning is more difficult than outdoor positioning because of complicated environment. Fingerprint is a technique proposed to sketch the characteristic of every indoor location by adopting time-consuming measurements in offline phase. To minimize overhead, virtual fingerprint construction...
With the increasing of wind power installed capacity, power peak-load regulation has become main restriction for wind power accommodation. With an aim at this problem, this paper suggests a novel method for solving wind power accommodation. Firstly, digging the inverse peak-load regulation capacity of cascade reservoirs, using adjustable cascade reservoirs capacity realizes an aim, when renewable...
A novel multiscale superpixel-based fusion classification approach is proposed for hyperspectral images in this study. Superpixels are considered as basic processing unit for spectral-spatial based classification. The proposed technique consists of three steps. In the first step, an improved superpixel segmentations are proposed to perform from coarse to fine scales for the original hyperspectral...
Spacecraft on-orbit serving is vital important for future space missions and is of interest of many countries. Relative motion determination is the major problem for spacecraft on-orbit servicing. Due to the advantages of monocular vision navigation system, it has been widely proposed for spacecraft approaching for the final stage. However, due to the model uncertainty and state mobility of the target...
This paper analyzes the influence of the anomalous temperature occurred at the near surface boundary layer of the atmosphere on the land surface temperature (LST) retrieval with the generalized split-window algorithm (GSW). The coefficients in the GSW algorithm corresponding to a series of overlapping ranging of the mean emissivity, the atmospheric water vapor content, and the LST are derived using...
An algorithm has been developed for retrieving instantaneous microwave land surface emissivity using brightness temperature and precipitable water vapor data. Unlike previous algorithms, the new technique does not need infrared land surface temperature as the input data, and overcomes the limitation of previous algorithms under cloudy conditions. Compared with the values from physical retrieval algorithm,...
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