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Since heat wave is currently one of the most important meteorological disasters, it has a significant impact on residents' health and social economy. The accurate identification and assessment of heat wave risk is an effective means to deal with this problem. In this paper, the hazard, vulnerability and regional comprehensive prevention ability factors were selected as the indexes for evaluating heat wave risk. The index weight was determined by the H-AHP method, and the spatial distribution map of the risk level of heat wave was calculated by the graph cascade method. The results show that there is a significant spatial difference in the risk of heat wave in the regions along the Jakarta-Bandung High-Speed railway. On the whole, the risk in the northern region is higher than that in the southern region, and the risk in the western region is higher than that in the eastern region. The high-risk areas are mainly concentrated in Jakarta, the capital of Indonesia. The medium-high-risk areas were mainly distributed in Jakarta's peripheral suburbs and Bandung City. The low-risk areas are distributed in the central region, forming a typical V-shaped distribution being high on both sides and low in the middle. The overall risk of heat wave in this region is at a medium level, with the medium-level risk area accounting for nearly 50%. With the exception of Jakarta, Bekasi, Bandung, and Cimahi cities, half or even more than half of the other counties are at medium-level risk. The area with low risk level accounts for the least, only 8.10%, mainly distributed in the northern part of Karawang county near the Java sea, and in the southwest part of Bandung county and West Bandung county with high forest coverage. In this paper, a method of heat wave risk assessment based on remote sensing is proposed, and spatial social and economic data are used, providing a new idea for heat wave risk assessment for countries along the Belt and Road region.

We discuss a novel task, Chorus Recognition, which could potentially benefit downstream tasks such as song search and music summarization. Different from the existing tasks such as music summarization or lyrics summarization relying on single-modal information, this paper models chorus recognition as a multi-modal one by utilizing both the lyrics and the tune information of songs. We propose a multi-modal Chorus Recognition model that considers diverse features. Besides, we also create and publish the first Chorus Recognition dataset containing 627 songs for public use. Our empirical study performed on the dataset demonstrates that our approach outperforms several baselines in chorus recognition. In addition, our approach also helps to improve the accuracy of its downstream task - song search by more than 10.6%., Comment: Accepted at the 30th International Conference on Artificial Neural Networks (ICANN 2021)

Deserts and sandy land in northern China are very susceptible to sandy desertification and are the main source of sand-dust storms of Asian dust. However, because of the complex factors involved, descriptions of the relationship between sandy desertification and surface characteristics in these regions are lacking. We monitored the surface characteristics and their changes in time using information about soil, vegetation, and landforms in the Badain Jaran Desert (BJD), Tengger Desert (TD), and Ulan Buh Desert (UBD) in the northern China. The monitoring was done using tasseled cap angle (TCA), disturbance index (DI), and topsoil grain size index (TGSI) from Moderate Resolution Imaging Spectroradiometer (MODIS) images combined with a decision tree classification. Results showed that the TD had higher topsoil fine sand content, and the ratio of non-vegetated to vegetated areas was similar with that in the UBD. Northeast-southwest coarse sand dunes with thin interdune (NECTI) dominated the BD, fine sand dunes (FSD) dominated the TD, and a combination of northeast-southwest coarse sand dunes with wide interdune (NECWI) and northwest-southeast coarse sand dunes with wide interdune (NWCWI) dominated the UBD. From 2000 to 2015, in the BJD the area of the NECTI, non-sand dune (Non) and potential sand sources (PSS) increased, whereas the area of the NECWI, FSD and NWCWI decreased, indicating a improve process in the BJD. In the TD, the area covered by Non increased, whereas the area covered by PSS, NECWI, NECTI, FSD, and NWCWI decreased from 2000 to 2015. The area covered by the various surface characteristic types fluctuated annually in the UBD from 2000 to 2015. Changes in surface characteristics reflect the combined effects of natural conditions and human activity. The findings of our study will assist scientists and policy makers in proposing different management techniques to combat sandy desertification for the different surface characteristics of these regions.

Two kinds of conductive polylactide fibers&mdash, polylactide pre-oriented yarns (PLA-POY) and PLA-drawn textured yarns (PLA-DTY) are prepared by coating method using ethyl acetate as solvent, multiwalled carbon nanotubes (MWCNTs) as conductive filler, and polyvinyl acetate (PVAc) as dispersing agent and coating agent. The PLA fibers are characterized by scanning electron microscope (SEM), Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), resistance meter, and tensile test. The results show that PLA-POY and PLA-DTY have been coated successfully by PVAc and MWCNTs. After PLA-POY fibers are treated by ethyl acetate, the highly porous structures form because of swelling and the subsequent solvent-induced crystallization of PLA-POY fibers with low crystallinity. This causes the tensile force to decrease. However, PVAc can improve the tensile force of the treated PLA-POY fibers. For PLA-DTY fibers, the effect of ethyl acetate on surface morphology is small. Therefore, the treated PLA-DTY fibers own higher tensile properties than original PLA-DTY fibers due to the existence of PVAc. With the increase of PVAc and MWCNTs, the conductive properties of the PLA fibers will increase. The electrical conductivity of PLA-POY and PLA-DTY fibers can reach 0.53 and 0.13 &micro, s/cm, respectively.

Timely understanding of the coastal accretion&ndash, erosion dynamics of the Yellow River Delta (YRD) can not only deepen the understanding of the evolution of the delta but also provide scientific support for water-sediment regulation (WSR) in the lower reaches of Yellow River and the implementation of a protection strategy for the Yellow River Estuary. In this long-term study, Landsat images from 1976 to 2018 were acquired, and the cloud processing platform of the Google Earth Engine was used for extraction of coastlines. On the basis of these coastlines, the area and accretion&ndash, erosion dynamics were analyzed. Then, after statistical analysis of the interannual and intra-annual variations in runoff and sediment, we discuss the relationship between the accretion&ndash, erosion dynamics and the annual runoff and sediment. The results show that (1) the coastline of the YRD lengthened first and then shortened, and the average annual growth rate was 1.48 km/a. (2) The land area of the YRD showed a significant accretionary trend before 1996, with an average annual growth rate of 28.60 km2/a. Then, the area gradually decreased from 1997 to 2001. After WSR was implemented in 2002, the accretion&ndash, erosion dynamics gradually became smooth, with an annual growth rate of 0.31 km2/a. (3) After WSR, the maximum annual sedimentation decreased by 79.70%. The average annual sediment discharge accounted for only 6.69% from November to March of the following year during the non-flood season. (4) With the continuous decrease in sediment discharge, the determination coefficient (R2) between the cumulative accretion&ndash, erosion area of the estuary and the annual sedimentation decreased from 0.98 in 1976&ndash, 1996 to 0.77 after 2002. Overall, although WSR has maintained a steady increase in delta land area, it cannot change the long-term decrease in the land area of the delta. The insights gained from our study can provide some references for related coastline research, and will be useful to science community and decision makers for coastal environmental monitoring, management, protection, and sustainable development of the YRD.

Polyphenylene sulfide (PPS)/organic clay nanocomposites were prepared by simple melt blending. A synthesized benzimidazolium salt was used to modify the sodium montmorillonite in order to improve the compatibility with the PPS. The nonisothermal crystallization kinetics of PPS/organic clay composites were investigated by differerntial scanning calorimetry(DSC). It was observed that the crystallization peak temperature of PPS/organic clay composites was higher than pure PPS at various cooling rates. Several models such as the Ozawa and Mo equation were used to characterize the nonisothermal cooling crystallization kinetics of the PPS/organic clay composites. The results indicated that the Ozawa equation was not successful, while the Mo equation was successful to describe the nanoisothermal ctystallization kinetics of PPS/organic clay nanocomposites. The results also indicated that organic clay not only served as heterogeneous nucleating agents for PPS crystallization at lower content but also restricted the mobility and diffusion of PPS chains at higher content. These results were further supported by the crystallization activation energy of the samples determined by the Kissinger method.

In recent years, the activity of the human has been more and more continual which caused the change of the coastal zone more active than before. So it is vital significant to accurately and quickly extract coastline and real-time monitor the changes. Many approaches have been developed to automatically extract coastline. After comprehensive comparison, it was found that combining mean-shift with region growing algorithm could extract the coastline very well. In this paper, the MNDWI was firstly used to roughly determine the range of shoreline. Then, mean-shift was applied to remove the noise, and finally the continuous coastline was extracted using the method of regional growth. Experiments show that the method could extract the continuous coastline accurately and quickly.

Highly porous polylactide (PLA) microfibers with the diameter of about 14 µm are prepared by melt-spinning and stretching core–sheath PLA fibers (CSF) and sequent treatment of ethyl acetate. The resultant pores are regular and elliptical. The average values of length of major axis and minor axis of elliptical pores are around 1 and 0.5 μm, respectively. This new and facile method can prepare porous PLA fibers on industrial scale, and nearly overcome all the shortcomings of melt-spinning and stretching method. In addition, highly porous structure in partially oriented poly(l-lactide) yarn (POY) can be also formed by treating POY using ethyl acetate. The obtained pores are irregular. In addition, the formation mechanism of pore structure in CSF is different with the one in POY. The former is the separation of row-nucleated lamellae induced by stretching while the latter is swelling and subsequent solvent-induced crystallization.

Polyphenylene sulfide (PPS)/clay composites were prepared by simple melt blending. Three different kinds of surfactants such as cetyltrimethyl ammonium bromide (CTAB), sodium dodecyl benzene sulfonate (SDBS), and synthetic 1,3-dihexadecyl-3H-benzimidazolium bromide (Bz) were used as organic modifiers for the organic modification process. The benzimidazolium-modified montmorillonite (Bz-MMT) and CTAB-modified MMT (CTAB-MMT) exhibited larger interlayer spacing than SDBS-modified MMT (SDBS-MMT), while SDBS-MMT and Bz-MMT exhibited higher thermal stability compared with the CTAB-MMT. The morphology of the PPS/organic MMT nanocomposites was evaluated by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The nanocomposites based on SDBS-MMT and Bz-MMT exhibited good overall dispersion of organic MMT with a mixed dispersion of intercalated and exfoliated structures. Differential scanning calorimetry and thermogravimetric analysis (TGA) were used to evaluate the thermal properties of PPS/organic MMT nanocomposites. The crystallization process of PPS in all nanocomposites was accelerated, and the crystallinity also increased, when compared with the pure PPS from the DSC analysis. The TGA analysis indicated that nanocomposites based on SDBS-MMT and Bz-MMT exhibited higher thermal stability than composites based on CTAB-MMT due to the well-dispersed nanoplatelets.

Cotton is a significant cash crop of China. Timely and accurate cotton area and yield estimation is useful for management decisions related to the cotton procurement and sales. This study is a first research on cotton area and yield estimation based on remote sensing at Zhanhua County which is one of the high-quality cotton production demonstration bases of China. After normalization of Enhanced Vegetation Index (EVI) time series derived from Huanjin 1 A/B satellite (HJ-1 A/B), decision tree classifier was used to identify the cotton, and then K-Means classifier was applied to estimate cotton yield. The results indicated an overall accuracy of 95% for the cotton area estimation and 91% for the cotton yield classification. With further validation, it suggests that this method can be used to timely achieve the cotton area and growth information of this region.

The Curie point depth of continental crust can reflect the regional tectonic pattern and geothermal structures. Analysis of magnetism is an efficient way to obtain the Curie point depth on a regional scale. This study systematically investigated the Curie point depth of Sulu ultrahigh pressure (UHP) metamorphic belt (33°40′N to 36°20′N and 118°E to 120°E, ca. 60 000 km 2 ), eastern China using aeromagnetic data. The results show that the Curie point depth of the Sulu region varies from 18.5 to 27 km. The shallowest Curie point depth (ca. 18.5 km) is located in Subei subsidence, where the estimated temperature gradient value is about 31.35 °C/km, which is comparable with the measured value of 30 °C/km. In addition, a two-dimensional numerical solution of the heat conduction was used to calculate the temperature field to a depth of 30 km along the profile from Tancheng to Lianshui with a length of 139 km. The steady state model solved using the finite element method shows that the temperature around the Curie point depth is about 585.36 °C, which is close to the Curie temperature (580 °C) of magnetite at atmospheric pressure. These results provide new insights into the tectonic and continuous thermal structures of the Sulu UHP metamorphic belt.

Based on the theories and methods of cartography on spatial pattern and temporal evolution in Geo-information Tupu (Carto-methodology in Geo-information, CMGI) and the quantitative measurements of pattern and process in landscape ecology, the methodology of landscape information Tupu in studying the swing process of the Yellow River (YR) over the Yellow River Delta (YRD) during 1855–2000 has been demonstrated. The main content includes: (1) methodology of landscape information Tupu; (2) evolution process Tupu of YR rump channels; (3) evolution process Tupu of the 7 pieces of subdeltas in YRD during 1855–2000; (4) landscape information Tupu of the modern YRD and the current YRD; (5) landscape information Tupu of YR rump channels on the 7 pieces of subdeltas during 1855–2000; and (6) corridor-matrix landscape information Tupu by YR swings. The methodology of landscape information Tupu here is still primary but we hope that it could provide a new tool for exploring an integrated research on spatiotemporal approaches for landscape “pattern and process”.

By using data on the 1:100 000 aeromagnetic anomalies of the Sulu orogenic belt, we designed three simulated geotraverses, in which deep seismic reflection and other geophysical investigations have been completed. Based on the features of magnetism of the three profiles, and under the constraints of deep seismic reflection data, together with the magnetism of the core petrology at the Chinese Continental Scientific Drilling (CCSD) pilot-hole and areal geology, the three inversions of magnetic anomalies are carried out. The characteristics of terrane structure are presented: the rocks are mostly composed of eclogite, marble, and gneiss at the depth of 5 km. At the depth between 5 and 7 km under the surface, inverse magnetic bodies are mainly the ultra high pressure metamorphic (UHPM) rock slices containing a lot of coesite-bearing eclogite. At the depth between 7 km and the bottom of upper crust are the rocks of the gneiss, granite and granite diorite that underwent ultra high pressure metamorphic process. Middle crust (10–19 km) is mostly composed of UHPM gneiss and granite that intruded later. The rocks of acid and basic granulite dominate the lower crust. Based on the inversed results of the three simulated geotraverses, we know that the UHPM rock slices of the three profiles are dipping north, stacking each other and being uplifted to the earth’s surface, which may be the result of the North China craton’s subduction and exhumation in the Triassic.

In order to determine the main types of pollution origins of the heavy metals of sediments of Lake Dong-hu, Wuhan, based on principle of principal components and the rule of picked-up information which is over 84% of original ones, we have analyzed twelve elements of thirty representative samples of 0 - 7 cm sediments of Lake Guozheng and Lake Tanglin, which are the main sub lake of Lake Donghu, Wuhan city. The results indicate that for Guozheng Lake sediments, the first pollution origin (56% ) is industry coal dust around the lake, the second origins (16% ) are tail gas, domestic sewage and rain flow, and the third parts(12% ) are industry sewage with e-lectroplate and press etc. For Lake Tanglin, the first pollution origin (65% ) is atmosphere dust which is from industry coal combustion, the second origins (17% ) are sewage with household, hospital and soil etc, and the third parts(9% ) are disused battery, newspapers and farming materials etc. Employing the comprehensive pollution indexes of heavy metals, which were calculated by root mean square on the background values, to evaluate the pollution degree of sediments of main sublakes of Lake Donghu, it is found that both of them belong to light contamination and the pollution degree of Lake Guozheng is higher than that of Lake Tanglin.

Poly(3-hydroxybutyrate) [P(3HB)] and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] are produced by various microorganisms as an intracellular carbon and energy reserve from agricultural feedstocks such as sugars and plant oils under unbalanced growth conditions. P(3HB) and P(3HB-co-3HV) have attracted the attention of academia and industry because of its biodegradability, biocompatibility, thermoplasticity, and plastic-like properties. This review first introduced the isodimorphism, spherulites, and molecular interaction of P(3HB) and P(3HB-co-3HV). In addition, the effects of 3HV content on the melting temperature and crystallization rate were discussed. Then the drawbacks of P(3HB) and P(3HB-co-3HV) including brittleness, narrow melt processing window, low crystallization rate, slow biodegradation rate in body, and so on were summarized. At last, the preparation, structure, and properties of P(3HB) and P(3HB-co-3HV) fiber were introduced.

The Wutai-Jining crustal cross-section is located in the central North China Craton. The upper crustal cross-section is represented by the Wutai granite-greenstone terrain and overlying post-Archean sedimentary rocks, the middle crust by the comparable Henshan and Fuping amphibolite- to granulite-facies terrains, and the upper lower crust by the granulite-facies Jining terrain. Correlation of measured seismic velocities of rocks from the crustal cross-section with data on seismic refractions suggests that the section is likely to represent a ca 30 km crust column with the 5 km thick lowermost crust being not exposed (Kern, H., Gao Shan, Liu Qingsheng, 1996. Earth Planet. Sci. Lett. 139, 439–455). Forty-four samples from the cross-section, some of which were used for measurements of seismic velocities and densities ( Kern et al., 1996 ), are analyzed for saturation magnetization ( J s ) and saturation isothermal remanent magnetization (SIRM). Rock magnetism depends primarily on metamorphic grade and thus on different depth of mineral equilibrium. Lithology plays a less important role. Rocks of greenschist-, amphibolite- and granulite-facies have average J s of 58.7, 686 and 1068 A/m, respectively. SIRM corresponds to 4.1, 77.9 and 138 A/m. Intermediate and felsic granulites from the Jining terrain show even higher magnetism than greenschist-facies metabasalts from the Wutai terrain. Variation coefficient ( V c ) of J s increases from the upper (62.2%) through the middle (64.3%) to the lower (144%) crust. Similarly, SIRM increases from 70.7 to 82.9 and to 165%. This documents considerably greater magnetic heterogeneity in the lower crust compared to the upper and middle crust. For the same lithology, magnetism ( J s and SIRM) of rocks from the Jining terrain is remarkably higher than that of rocks from the Archean Taihua granulite terrain at the southern margin of the North China craton adjacent to the Qinling orogenic belt. This is attributed to lower heat flow (52–56 mWm −2 ) in the central North China craton compared to the southern margin of the craton (62 mWm −2 ). Combined with longwavelength magnetic anomalies from Magsat, it is inferred that the mafic granulite in the cross-section is responsible for lower crustal magnetization in the region. They are comparable to magnetization of lower crust from shield areas in other parts of the world. The strong magnetism of the granulites under this investigation and pyroxenite xenoliths from the nearby Hannuoba alkaline basalt suggest that the magnetic bottom of the lithosphere in the central North China craton lies at the base of the crust or the uppermost mantle.

114 m of Uppermost Cretaceous to Lowermost Tertiary continental redbeds and their magneto‐stratigraphy are described. The palaeomagnetic directions suggest that a clockwise rotation of around 50 degrees of the South China block took place later than Lower Paleocene time. The last dinosaur nests occur rather high up in magnetochrone 29R. This suggests that the Nanxiong dinosaur population was present much later than the corresponding population of Aix‐en‐Provence, France. The last nests in France are not present in sediments younger than the upper part of magnetochrone 30N.

Active Power Filter (APF) is usually used to compensate the harmonic currents which are generated by the nonlinear load, and its compensation performance mainly depends on the estimation of APF mathematic model, instruction signal of harmonic currents and design of controller. Traditional control APF uses the average mathematic model, and PI controller and its instruction signal of harmonic currents is obtained by load harmonic currents. This paper adopts the energy shaping repetitive control technology to correct the output current waveform of three-phase three-wire shunt active power filter, Energy Shaping Control can guarantee APF system dynamic stability. Hamiltonian model of APF is built. Instruction signal of harmonic currents is obtained by PI controller of the voltage harmonic where APF is located, in this way, load harmonic currents are not necessary in the control process. The controller design procedure is analyzed in detail. Theoretical analysis and experimental results demonstrate the validity of the proposed method, the filtering performance is improved obviously.