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The auxiliary transportation system for coal mine is an essential system for transporting personnel, important materials, and equipment in coal mine enterprises. Realizing unmanned driving in coal mine is an inevitable requirement for improving transportation efficiency and ensuring transportation safety, and is also the only way to implement the national coal mine intelligent construction deployment. The mine unmanned driving relies on accurate and real-time environmental perception. By using onboard perception devices such as LiDAR and millimeter wave radar, as well as collaborative perception supported by the Internet of vehicles, the precise and detailed perception of local vehicles and even the entire mine is achieved. A systematic review is conducted on the research status of unmanned driving environment perception technology in mines. It is pointed out that the special environment of coal mine will lead to varying degrees of degradation in the performance of mine onboard perception devices. The advantages and disadvantages of various onboard perception devices are summarized. The key technologies of mine unmanned driving environment perception are elaborated in detail. The technologies include single-sensor obstacle recognition methods based on visible light images or laser point clouds, the classification of multi-sensor fusion perception, and multi-sensor fusion methods such as visible light images+laser point clouds, visible light images+millimeter wave point clouds, visible light images+laser point clouds+millimeter wave point clouds, 4D millimeter wave radar+other perception devices. The technologies include the implementation, data processing methods of intelligent networked collaborative perception, and their promoting effects on unmanned driving. The technologies also include methods for detecting and recognizing traffic signs in underground roadways, and methods for segmenting the driving area of underground trackless rubber wheeled vehicles and tracked locomotives in roadways. The development direction of unmanned driving environment perception technology in mines is pointed out. It is recommended to improve the fusion performance of multiple sensors in mines, study adaptive perception algorithms in mines, and break through the intelligent networked collaborative perception technology in mines.

Biophysical effects of land cover changes on land surface temperature (Ts), including two effects, that is, radiative effects (caused by surface albedo changes) versus non‐radiative effects (caused by changes in the energy flux distribution), have attracted the attention of many researchers. However, the uncertainties of land use and land cover (LULC) and vegetation schemes on non‐radiative effects, and the roles of non‐radiative effects on Ts, remain uncertain. In this study, we investigate the local impact of LULC differences by comparing Noah with multiparameterization (Noah‐MP) land model simulations with different LULC data sets and those with vegetation schemes whether they include interactive canopies. We attribute Ts changes induced by LULC differences obtained from Noah‐MP simulations to radiative and non‐radiative effects over East Asia based on the decomposed temperature metric theory. The results indicate that vegetation cools Ts over urban regions by 4.0–6.0°C. Grassland and cropland decrease the Ts over barren regions. Forests are warmer (cooler) than grassland and cropland in high latitudes (in mid and low latitudes). Grassland is cooler than cropland. However, the magnitude of Ts changes induced by these differences is lower than that induced by differences between vegetation and urban. The non‐radiative effect generally explains more than 50% of the local changes in Ts. The interactive canopies enlarge Ts changes for afforestation or replacements of urban region by vegetation. The effect of uncertainties in LULC data sets is negligible. This study highlights the importance of non‐radiative biophysical effects and interactive canopies on local changes in Ts. Plain Language Summary: The biophysical effects of land cover changes on land surface temperature (Ts) cannot be ignored while assessing the impact of land cover changes. The role of non‐radiative effect, one of the two forcing effects of the biophysical effects, remains uncertain. In this study, we investigate the local impact of different land cover types on Ts by comparing land model simulations with different land cover data sets and vegetation schemes whether they include interactive canopies. The non‐radiative effect dominates the local changes in Ts over East Asia. The interactive canopies could enlarge the Ts changes for afforestation or replacements of urban region by vegetation. However, the effect of uncertainties in land cover data sets on Ts changes and non‐radiative effect induced by different land cover types is negligible. Key Points: Forests, grassland, and cropland largely cool the land surface temperature compared with urban region and the barren regionThe non‐radiative effect generally explains more than 50% of the local changes in land surface temperatureThe interactive canopies enlarge the changes in Ts for conversions from short vegetation to tall vegetation or urban to vegetation [ABSTRACT FROM AUTHOR]

Surface albedo is a crucial parameter in land surface radiation budget. As bias exists between the model simulated and observed surface albedo, data assimilation is an important method to improve the simulation results. Moreover, surface albedo is associated with the wavelength of the sunlight. So, solar radiation partitioning is important to parameterize the surface albedo. In this paper, the moderate resolution imaging spectroradiometer- (MODIS-) retrieved direct visible, direct near-infrared, diffuse visible, and diffuse near-infrared surface albedos were assimilated into the integrated urban land model (IUM). The solar radiation partitioning method was introduced to parameterize the surface albedo. Based on the albedo data from MODIS and the solar radiation partitioning method, the surface albedo data set for the Beijing municipal area was generated. Based on the surface albedo data set and the IUM, the impacts of the surface albedo on the surface radiation budget were discussed quantitatively. Surface albedo is inversely proportional to the net radiation. For urban areas, after assimilation, the annual average net radiation decreases about 5.6%. For cropland, grassland, and forest areas, after assimilation, the annual average net radiations increase about 20.2%, 24.3%, and 18.7%, respectively. [ABSTRACT FROM AUTHOR]

Surface albedo is one of the key parameters of land surface radiation and energy balance. As surface albedoes for visible and near-infrared solar radiation are quite different, solar radiation partitioning is important to parameterize the total surface albedo and upward solar radiation. In this paper, a surface albedo parameterization scheme was introduced and a solar radiation partitioning method was developed to improve the simulation of the upward solar radiation. The simulation results were validated in a hinterland site of the Taklimakan Desert. The surface albedo is not only associated with the soil moisture, but associated with the solar zenith angle. The solar radiation partitioning method considers the joint influences of cloud cover, near-surface air pressure, and solar zenith angle and was compared with the method using the Simple Biosphere Model version 3 (SiB3). The total albedo depends on the partitioning of the total visible and near-infrared radiations. The results indicate the surface albedo parameterization scheme is important to parameterize the upward solar radiation. The new solar radiation partitioning method could improve the simulation result. [ABSTRACT FROM AUTHOR]

We present a method for the fast computation of the intersection between a ray and the geometry of a scene. The scene geometry is simplified with a 2D array of voxelizations computed from different directions, sampling the space of all possible directions. The 2D array of voxelizations is compressed using a vector quantization approach. The ray-scene intersection is approximated using the voxelization whose rows are most closely aligned with the ray. The voxelization row that contains the ray is looked up, the row is truncated to the extent of the ray using bit operations, and a truncated row with non-zero bits indicates that the ray intersects the scene. We support dynamic scenes with rigidly moving objects by building a separate 2D array of voxelizations for each type of object, and by using the same 2D array of voxelizations for all instances of an object type. We support complex dynamic scenes and scenes with deforming geometry by computing and rotating a single voxelization on the fly. We demonstrate the benefits of our method in the context of interactive rendering of scenes with thousands of moving lights, where we compare our method to ray tracing, to conventional shadow mapping, and to imperfect shadow maps. [ABSTRACT FROM AUTHOR]

Land surface evaporation is not only an important parameter in natural land surface modeling, but a crucial important parameter in urban hydrology modeling. A whole-layer soil evaporation scheme was developed in the integrated urban land model (IUM) to improve the soil evaporation simulation. The impervious surface evaporation (ISE) was used as a component of urban water balance equation. In this paper, the integrated urban land model was validated at one desert site and six urban road sites to emphasize the improvement in the evaporation simulations for arid and urban areas. A sensitivity analysis was implemented in seven basins to expand the utility of the whole layer soil evaporation scheme. For the urban road sites, the validation results indicate that imperious surface evaporation (ISE) plays a crucial role in road surface temperature (RST) simulations on rainy days. For the desert site, the validation results show that the inner layer evaporation is very important in arid regions. For the basins, the analysis results indicate that the relative monthly mean differences in the evapotranspiration (ET) between the simulations with (IUM) and without (Common Land Model (CoLM)) considering the inner layer evaporation range from −8% to 8%, which is proportional to the degree of dryness. In arid areas, especially deserts, the inner layer soil evaporation could not be neglected. [ABSTRACT FROM AUTHOR]

An integrated urban land model (IUM) was developed based on the Common Land Model (CoLM). A whole layer soil evaporation parameterization scheme was developed to improve soil evaporation simulation especially in arid areas. For the urban underlying surface, the energy and water balance model were modified; urban land parameters such as the anthropogenic heat (AH), albedo, surface roughness length, imperious surface evaporation etc. were also reparameterized. IUM was validated and compared with CoLM and the urbanized high-resolution land data assimilation system (u-HRLDAS) in single and regional scale. The validation results indicate that IUM can improve the simulation of land surface parameters and land-atmosphere interaction fluxes. [ABSTRACT FROM AUTHOR]

We investigate the multiple attribute decision making problems with the hesitant triangular fuzzy information. Then, we have developed the hesitant triangular fuzzy Einstein correlated averaging (HTFECA) operator. The prominent characteristic of the operators is that they can not only consider the importance of the elements or their ordered positions, but also reflect the correlation among the elements or their ordered positions. We have applied the HTFECA operators to multiple attribute decision making for evaluating the wireless network security with hesitant triangular fuzzy information. Finally an illustrative example for evaluating the wireless network security has been given to show the developed method. [ABSTRACT FROM AUTHOR]

Impervious surface temperature is a key parameter in impervious surface energy balance. Urban canopy models are now widely used to simulate impervious surface temperatures, but the physical assimilation method for the urban canopy model is still under development and the use of high temporal resolution observation data are limited. In this paper, a physical assimilation method was used to improve the simulation of the impervious surface temperature for the first time. A variational assimilation method was developed and coupled with the integrated urban land model, using the impervious surface energy balance equation as the adjoint physical constraint. The results showed that when the observed impervious surface temperature data of every timestep were assimilated into the integrated urban land model, the bias of the impervious surface temperature was reduced about 86 %. For the operational run, the observed data were assimilated twice per day, and the bias of the impervious surface temperature was reduced by about 78%. [ABSTRACT FROM AUTHOR]