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Efficient soybean mapping is critical for agricultural production and yield prediction. However, current sample-driven soybean mapping methods heavily rely on large representative sample datasets, limiting the interpretability of physical mechanisms. Besides, sample-free methods failed to exploit key features that differentiate soybean from other crops, especially Chlorophyll content. Misclassification errors persist and spatiotemporal generalization remains limited. Therefore, this study develops a novel Soybean Mapping Composite Index (SMCI) within a precise Global Optimal Time Window (GOTW). It integrates unique features of soybean Chlorophyll content, canopy water content, and canopy greenness by coupling three red-edge bands (RE2, RE3, and RE4), one near-infrared band, one shortwave infrared band, and two feature indices (Enhanced Vegetation Index and Green Chlorophyll Vegetation Index). The novel index was applied to soybean mapping at six sites in four major soybean producing countries (China, Argentina, Brazil, and the United States) from 2019 to 2021, using an optimal threshold of 3.25. Within the GOTW, the index responds better to spectral features and improves soybean separability. The average overall accuracy (OA: 91%) and average Kappa coefficient (Kappa: 0.83) for the novel index at all sites outperformed the traditional sample-driven Random Forest (RF) method (OA: 84%, Kappa: 0.70) and the existing sample-free index-based Greenness and Water Content Composite Index (GWCCI) (OA: 81%, Kappa: 0.64). Furthermore, interannual transfer experiments consistently showed high accuracy, demonstrating robust spatiotemporal transferability. The proposed SMCI index meets the need for a lightweight and stable soybean mapping tool and serves as a valuable reference for efficient global crop mapping. [ABSTRACT FROM AUTHOR]

Environmental factors, such as culture, are known to shape individual variation in brain activity including spontaneous activity, but less is known about their population-level effects. Eastern and Western cultures differ strongly in their cultural norms about relationships between individuals. For example, the collectivism, interdependence and tightness of Eastern cultures relative to the individualism, independence and looseness of Western cultures, promote interpersonal connectedness and coordination. Do such cultural contexts therefore influence the group-level variability of their cultural members' spontaneous brain activity? Using novel methods adapted from studies of inter-subject neural synchrony, we compare the group-level variability of resting state EEG dynamics in Chinese and Canadian samples. We observe that Chinese subjects show significantly higher inter-subject correlation and lower inter-subject distance in their EEG power spectra than Canadian subjects, as well as lower variability in theta power and alpha peak frequency. We demonstrate, for the first time, different relationships among subjects' resting state brain dynamics in Chinese and Canadian samples. These results point to more idiosyncratic neural dynamics among Canadian participants, compared with more shared neural features in Chinese participants. [ABSTRACT FROM AUTHOR]

An approach is developed to study temporal behavior of the active region overheating in high-power semiconductor lasers (λ = 1060 nm) with an ultrawide aperture (800 μm) operating in a quasi-continuous regime of pumping by current pulses with an amplitude of 21 A, a duration of 1 ms, and a repetition rate of 10 Hz. The approach is based on measuring the lasing dynamics with spectral selection. The lasing spectrum analysis shows that the region of the rising edge, where the amplitude of the current pulse increases, is characterized by a maximum red-shift rate of 30 nm ms–1, which is due to both thermal and nonthermal effects. The pulse region corresponding to a constant pump current amplitude is characterized only by a thermal red shift of the lasing spectrum long-wavelength edge at a rate of ~1 nm ms–1. The obtained experimental active region overheating is 2.78°C for the constant pump current amplitude range, which agrees with the calculated overheating of 3.08°C for the pump conditions under study. [ABSTRACT FROM AUTHOR]

The discriminating information about dysarthria exists at the fine level in the short-time Fourier transform magnitude spectra (STFT-MS). To capture the discriminating information present in STFT-MS using Mel-frequency cepstral coefficients (MFCCs), this paper firstly studied the role of increasing the size of Mel-filterbank and inverse Mel-filterbank. A novel feature extraction technique is then proposed for the assessment of dysarthria using speech. In the proposed approach, the STFT-MS is processed through an accumulator (digital integrator) to capture the spectral dynamics (SD). The accumulator output over a frequency range is a growing or decaying function of frequency depending on the peaks and valleys present within that region due to the pitch and resonance structure of the vocal tract system. The SD over a band of frequency is computed from the accumulator output by finding non-local differences between frequency points placed linearly in non-overlapping mode. The SDs are logarithmically compressed (LCSD) to normalize the magnitude of SD computed in different frequency regions. The LCSD represents (M) dimensional feature vector when it is computed at M linearly spaced frequency points. The i-vector-based dysarthric-level assessment system on the universal access speech reported in this study shows that the performance of the MFCC feature improves significantly by increasing the Mel-filterbank size. The MFCCs computed from the inverse Mel-filterbank (IMFCCs) contain additional information to MFCCs. The use of LCSD provides improved performance than MFCCs and IMFFCs and is also provides additional to MFCCs. [ABSTRACT FROM AUTHOR]

• Noise-like square pulse obtains a square shape in the spectral domain. • The pulse demonstrates a spectral resonance with a 3-dB variation: 10–20 nm. • Simulation approximately reproduced the flat-topped spectra and spectral resonance. • Analysis shows that the flat gain dispersion accounts for the flat spectral peaks. We report the generation of a series of noise-like square pulses (NLSPs) at 2 μm in a figure-8 Tm-doped fiber laser. The NLSP demonstrates a square shape as well in the spectral domain and possesses a resonant property in spectrum similar to that in time. The spectral resonance ranges from 10 nm to about 20 nm under an appropriate control of polarization, an indication of its wide mode-locking regime. The unique spectral dynamics exhibits a strong polarization dependence, subject to the nonlinear mode-locking mechanism. A subsequent numerical simulation shows that a uniform gain dispersion distribution accounts for the forming of the flat-topped spectra. [ABSTRACT FROM AUTHOR]