Climate Normalized Spatial Patterns of Evapotranspiration Enhance the Calibration of a Hydrological Model

Spatial pattern-oriented evaluations of distributed hydrological models have contributed towards an improved realism of hydrological simulations. This advancement has been supported by the broad range of readily available satellite-based datasets of key hydrological variables, such as evapotranspiration (ET). At larger scale, spatial patterns of ET are often driven by underlying climate gradients, and with this study, we argue that gradient dominated patterns may hamper the potential of spatial pattern-oriented evaluation frameworks. We hypothesize that the climate control of spatial patterns of ET overshadows the effect model parameters have on the simulated patterns. To address this, we propose a climate normalization strategy. This is demonstrated for the Senegal River basin as a modeling case study, where the dominant north-south precipitation gradient is the main driver of the observed hydrological variability. We apply the mesoscale Hydrological Model (mHM) to model the hydrological cycle of the Senegal River basin. Two multi-objective calibration experiments investigate the effect of climate normalization. Both calibrations utilize observed discharge (Q) in combination with remote sensing ET data, where one is based on the original ET pattern and the other utilizes the normalized ET pattern. As objective functions we applied the Kling-Gupta-Efficiency (KGE) for Q and the Spatial Efficiency (SPAEF) for ET. We identify parameter sets that balance the tradeoffs between the two independent observations and find that the calibration using the normalized ET pattern does not compromise the spatial pattern performance of the original pattern. However, vice versa, this is not necessarily the case, since the calibration using the original ET pattern showed a poorer performance for the normalized pattern, i.e., a 30% decrease in SPAEF. Both calibrations reached comparable performance of Q, i.e., KGE around 0.7. With this study, we identified a general shortcoming of spatial pattern-oriented model evaluations using ET in basins dominated by a climate gradient, but we argue that this also applies to other variables such as, soil moisture or land surface temperature.

Does working from home work? Experience of working from home and the value of hybrid workplace post-COVID-19

Purpose This study aims to understand how knowledge workers working from home during COVID-19 changed their views on physical work environments and working-from-home practices. Design/methodology/approach This study conducted a survey targeting workers in the USA recruited via Amazon Mechanical Turk. A total of 1,651 responses were collected and 648 responses were used for the analysis. Findings The perceived work-life balance improved during the pandemic compared to before, while the balance of physical boundaries between the workplace and home decreased. Workplace flexibility, environmental conditions of home offices and organizational supports are positively associated with productivity, satisfaction with working from home and work-life balance during the pandemic. Research limitations/implications While the strict traditional view of “showing” up in the office from Monday through Friday is likely on the decline, the hybrid workplace with flexibility can be introduced as some activities are not significantly affected by the work location, either at home-based or corporate offices. The results of this study also highlight the importance of organizations to support productivity and satisfaction in the corporate office as well as home. With the industry collaboration, future research of relatively large sample sizes and study sites, investigating workers’ needs and adapted patterns of use in home-based and corporate offices, will help corporate real estate managers make decisions and provide some level of standardization of spatial efficiency and configurations of corporate offices as well as essential supports for home offices. Originality/value The pandemic-enforced working-from-home practices awaken the interdependence between corporate and home environments, how works are done and consequently, the role of the physical workplace. This study built a more in-depth understanding of how workers who were able to continue working from home during COVID-19 changed or not changed their views on physical work environments and working-from-home practices.

LIGHTWEIGHT AND MULTI-PURPOSE PARTITION FOR VERTICAL HOUSING

Vertical housings have been developed to solve housing quality degradation due to rapid urbanization. These housings are often lack of privacy and comfort, since the lay-out mostly consists of one open plan space with limited area. This paper presents a lightweight and multi-purpose partition to improve the living quality in vertical housings. The lightweight characteristic is intended to minimize structural loads, while the multi-purpose property allows the partition to be transformed into some furniture for spatial efficiency. A literature review and material surveys were performed prior to material selection and the design process. Then, physical model experiments were carried out to simulate the installation process and the transformation process of the partition modules into some furniture. Result show that the partition’s weight is only 11-36.7% of the common partition wall, and when installed, the transformable property enables an adaptable space which can be adjusted to the occupants’ different conditions.

Mapping Mineral Prospectivity Using a Hybrid Genetic Algorithm–Support Vector Machine (GA–SVM) Model

Machine learning (ML) as a powerful data-driven method is widely used for mineral prospectivity mapping. This study employs a hybrid of the genetic algorithm (GA) and support vector machine (SVM) model to map prospective areas for Au deposits in Karamay, northwest China. In the proposed method, GA is used as an adaptive optimization search method to optimize the SVM parameters that result in the best fitness. After obtaining evidence layers from geological and geochemical data, GA–SVM models trained using different training datasets were applied to discriminate between prospective and non-prospective areas for Au deposits, and to produce prospectivity maps for mineral exploration. The F1 score and spatial efficiency of classification were calculated to objectively evaluate the performance of each prospectivity model. The best model predicted 95.83% of the known Au deposits within prospective areas, occupying 35.68% of the study area. The results demonstrate the effectiveness of the GA–SVM model as a tool for mapping mineral prospectivity.

A Miniaturized Quad-Stopband Frequency Selective Surface with Convoluted and Interdigitated Stripe Based on Equivalent Circuit Model Analysis

This paper presents a miniaturized frequency selective surface (FSS) based on the convoluted and interdigitated stripe with multiple narrow passbands/wide stopbands in the L-/S-/C-/X-/Ku-/K-band. By using the convoluted and interdigitated stripe, the coupling inside is well controlled, so that the spatial efficiency is maximized to provide a high miniaturization. An equivalent circuit model is presented to reveal the working mechanism of the proposed FSS. The proposed structure forms four transmission band rejections of 3 dB in 1–6.65 GHz, 8.35–16.9 GHz, 18.0–24 GHz, and 24.50–27.84 GHz. The size of the unit cell is 0.09λ0 × 0.09λ0, where λ0 is the wavelength of the first resonance frequency. The proposed FSS has a good angle stability and polarization stability in a scanning range up to 60°. For verification, an FSS prototype has been fabricated and measured. The measured results were in agreement with the simulated results. The proposed FSS can be used in practical applications such as radomes, antenna reflectors, and spatial filters.

Gradient Boosting Estimation of the Leaf Area Index of Apple Orchards in UAV Remote Sensing

The leaf area index (LAI) is a key parameter for describing the canopy structure of apple trees. This index is also employed in evaluating the amount of pesticide sprayed per unit volume of apple trees. Hence, numerous manual and automatic methods have been explored for LAI estimation. In this work, the leaf area indices for different types of apple trees are obtained in terms of multispectral remote-sensing data collected with an unmanned aerial vehicle (UAV), along with simultaneous measurements of apple orchards. The proposed approach was tested on apple trees of the “Fuji”, “Golden Delicious”, and “Ruixue” types, which were planted in the Apple Experimental Station of the Northwest Agriculture and Forestry University in Baishui County, Shaanxi Province, China. Five vegetation indices of strong correlation with the apple leaf area index were selected and used to train models of support vector regression (SVR) and gradient-boosting decision trees (GBDT) for predicting the leaf area index of apple trees. The best model was selected based on the metrics of the coefficient of determination (R2) and the root-mean-square error (RMSE). The experimental results showed that the gradient-boosting decision tree model achieved the best performance with an R2 of 0.846, an RMSE of 0.356, and a spatial efficiency (SPAEF) of 0.57. This demonstrates the feasibility of our approach for fast and accurate remote-sensing-based estimation of the leaf area index of apple trees.

Clutter cancellation in passive radar using batch-based CLEAN technique

Passive radar (PR) systems need to detect the presence of a target response, which is many orders of magnitude weaker than the clutter (direct signal and multipath). Indeed, the clutter cancellation is a key stage within a PR processing scheme. One of the most effective techniques in this field is using the CLEAN approach. In this paper, the batch-based CLEAN technique based on GMP and FFT has been proposed, which can speed up the computational processing and have better cancellation gain. Furthermore, segmenting operation can be applied to the signal obtained over long time. It is helpful to enhance temporal or spatial efficiency and overcome effect of time-varying clutter. Experiment results with simulated and real passive radar data verify the effectiveness of the proposed algorithm.

Chinese Pattern of Urban Development Quality Assessment: A Perspective Based on National Territory Spatial Planning Initiatives

The State Council of the People’s Republic of China issued the National Territory Spatial Planning Outline (2016–2030), which is a fundamental guide and blueprint for China to achieve its Sustainable Development Goals (SDGs). Based on its sustainable-city initiatives, this paper establishes a “four-space (4S)” assessment framework, and measured the urban development quality (UDQ) of 336 cities in China. Then we analyzed the spatial patterns of UDQ, and identified the main obstacles. Our results show that there is considerable room for improvement in UDQ in China. The spatial pattern of UDQ shows that the eastern economic zone score is higher than the western score and the northern lower than the southern. The spatial efficiency, structure, and quality in Chinese cities have significant hierarchical structure, while the form pattern is complicated. The most important obstacle to China’s high-quality development is spatial efficiency. The most significant limiting indicator is the industrial structure, followed by land output level and land consumption per unit GDP. Our findings help enhance the effectiveness of National Territory Spatial Planning policy implementation and guide China’s urban planning and management to achieve sustainability.

Synthetic algal-bacteria consortia for space-efficient microalgal growth in a simple hydrogel system

Photosynthetic microalgae are an attractive source of food, fuel, or nutraceuticals, but commercial production of microalgae is limited by low spatial efficiency. In the present study we developed a simple photosynthetic hydrogel system that cultivates the green microalga, Marinichlorella kaistiae KAS603, together with a novel strain of the bacteria, Erythrobacter sp. We tested the performance of the co-culture in the hydrogel using a combination of chlorophyll-a fluorimetry, microsensing, and bio-optical measurements. Our results showed that growth rates in algal–bacterial hydrogels were about threefold enhanced compared to hydrogels with algae alone. Chlorophyll-a fluorimetry–based light curves found that electron transport rates were enhanced about 20% for algal–bacterial hydrogels compared to algal hydrogels for intermediate irradiance levels. We also show that the living hydrogel is stable under different environmental conditions and when exposed to natural seawater. Our study provides a potential bio-inspired solution for problems that limit the space-efficient cultivation of microalgae for biotechnological applications.

Crosstalk characterization in homogeneous multicore fiber using discrete changes model under bidirectional propagation

For the first time, the discrete changes model has been explored for crosstalk estimation under the bidirectional propagation condition. Crosstalk characterization in homogeneous multicore fiber (MCF) has been discussed, with different crosstalk estimation methods, such as, conventional model for perfectly homogeneous core, discrete changes model for real homogeneous core, and propagation direction interleaving (PDI) approach for backward propagation. The forward crosstalk expression under bending and twisting conditions, derived by the authors, has been utilized to visualize the impact of fiber twisting over a wide range. Discrete changes model has been analyzed for backward crosstalk, in order to observe the XT behavior for deterministic bending and twisting effects. For the crosstalk analysis in bidirectional propagation, 12-core MCF has been used, with circular lattice and square lattice arrangements for single-mode propagation. Moreover, for optimization and crosstalk suppression, trench-assisted core and PDI technique have been used to obtain the significantly low crosstalk in limited cladding diameter of 200 µm. The influence of fiber length and wavelength has been exhibited on crosstalk performance. The worst crosstalk level, and relative spatial efficiency in these MCFs have been compared with recently reported works.