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Existing dehazing approaches struggle to process real-world hazy images owing to the lack of paired real data and robust priors. In this work, we present a new paradigm for real image dehazing from the perspectives of synthesizing more realistic hazy data and introducing more robust priors into the network. Specifically, (1) instead of adopting the de facto physical scattering model, we rethink the degradation of real hazy images and propose a phenomenological pipeline considering diverse degradation types. (2) We propose a Real Image Dehazing network via high-quality Codebook Priors (RIDCP). Firstly, a VQGAN is pre-trained on a large-scale high-quality dataset to obtain the discrete codebook, encapsulating high-quality priors (HQPs). After replacing the negative effects brought by haze with HQPs, the decoder equipped with a novel normalized feature alignment module can effectively utilize high-quality features and produce clean results. However, although our degradation pipeline drastically mitigates the domain gap between synthetic and real data, it is still intractable to avoid it, which challenges HQPs matching in the wild. Thus, we re-calculate the distance when matching the features to the HQPs by a controllable matching operation, which facilitates finding better counterparts. We provide a recommendation to control the matching based on an explainable solution. Users can also flexibly adjust the enhancement degree as per their preference. Extensive experiments verify the effectiveness of our data synthesis pipeline and the superior performance of RIDCP in real image dehazing., Acceptted by CVPR 2023

Soil moisture is an essential component for the planetary balance between land surface water and energy. Obtaining long-term global soil moisture data is important for understanding the water cycle changes in the warming climate. To date several satellite soil moisture products are being developed with varying retrieval algorithms, however with considerable missing values. To resolve the data gaps, here we have constructed two global satellite soil moisture products, i.e., the CCI (Climate Change Initiative soil moisture, 1989–2021; CCIori hereafter) and the CM (Correlation Merging soil moisture, 2006–2019; CMori hereafter) products separately using a Convolutional Neural Network (CNN) with autoencoding approach, which considers soil moisture variability in both time and space. The reconstructed datasets, namely CCIrec and CMrec, are cross-evaluated with artificial missing values, and further againt in-situ observations from 12 networks including 485 stations globally, with multiple error metrics of correlation coefficients (R), bias, root mean square errors (RMSE) and unbiased root mean square error (ubRMSE) respectively. The cross-validation results show that the reconstructed missing values have high R (0.987 and 0.974, respectively) and low RMSE (0.015 and 0.032 m3/m3, respectively) with the original ones. The in-situ validation shows that the global mean R between CCIrec (CCIori) and in-situ observations is 0.590 (0.581), RMSE is 0.093 (0.093) m3/m3, ubRMSE is 0.059 (0.058) m3/m3, bias is 0.032 (0.037) m3/m3 respectively; CMrec (CMori) shows quite similar results. The added value of this study is to provide long-term gap-free satellite soil moisture products globally, which helps studies in the fields of hydrology, meteorology, ecology and climate sciences.

International audience

Precipitation, as an important component of the Earth’s water cycle, plays a determinant role in various socio-economic practices. Consequently, having access to high-quality and reliable precipitation datasets is highly demanded. Although Gridded Precipitation Products (GPPs) have been widely employed in different applications, the lack of quantitative assessment of GPPs is a critical concern that should be addressed. This is because the inherent errors in GPPs would propagate into any models in which precipitation values are incorporated, introducing uncertainties into the final results. This paper aims to quantify the capability of six well-known GPPs (TMPA, CHIRPS, PERSIANN, GSMaP, IMERG, and ERA5) at multiple time scales (daily, monthly, and yearly) using in situ observations (over 1.7 million) throughout Iran over the past two decades (2000–2020). Both continuous and categorical metrics were implemented for precipitation intensity and occurrence assessment based on the point-to-pixel comparison approach. Although all metrics did not support the superior performance of any specific GPP, taking all investigations into account, the findings suggested the better performance of the Global Satellite Mapping of Precipitation (GSMaP) in estimating daily precipitation (CC = 0.599, RMSE = 3.48 mm/day, and CSI = 0.454). Based on the obtained continuous metrics, all the GPPs had better performances in dry months, while this did not hold for the categorical metrics. The validation at the station level was also carried out to present the spatial characteristics of errors throughout Iran, indicating higher overestimation/underestimation in regions with higher precipitation rates. The validation analysis over the last two decades illustrated that the GPPs had stable performances, and no improvement was seen, except for the GSMaP, in which its bias error was significantly reduced. The comparisons on monthly and yearly time scales suggested the higher accuracy of monthly and yearly averaged precipitation values than accumulated values. Our study provides valuable guidance to the selection and application of GPPs in Iran and also offers beneficial feedback for further improving these products.

This review summarizes recent research on the molecular design, optical, and electronic properties of annulated borepins, silepins, and phosphepins, with emphasis on their structure–property relationships at the molecular level.1 Introduction2 Borepins3 Silepins4 Phosphepins5 Summary and Outlook

Solar radiation plays a pivotal role in the energy balance at the Earth's surface, evaporation, snow melting, water requirements of plants, and hydrological control of catchments. In this work, performance of ERA-Interim (a reanalysis dataset) was examined to estimate solar radiation at Ahvaz, BandarAbbas, and Kermanshah weather stations representing the even spatial distribution over Iran using eight empirical models and an artificial intelligence-based model (SVM: Support Vector Machine). In the calibration set, SVM exhibited the best performance with RMSEs of 249, 299 and 437 J.cm−2.day−1 at the aforementioned stations, respectively. In validation set, SVM reduced the errors in the estimates of solar radiation by 2.5 and 7.3 percent compared to the best empirical model at Ahvaz station (Abdallah model, RMSE = 242 J.cm−2.day−1) and Kermanshah station (Angstrom-Prescott model, RMSE = 315 J.cm−2.day−1), respectively. During the validation at BandarAbbas station, Bahel and Abdallah model (RMSE = 309 J.cm−2.day−1), Angstrom-Prescott model (RMSE = 310 J.cm−2.day−1) and SVM (RMSE = 312 J.cm−2.day−1) showed a relatively similar performance. The results also showed that the ERA-Interim dataset can be a comparatively suitable alternative to some of the empirical models, where radiation or the input parameters of empirical models are not directly measured, with RMSEs ​​of 382.81, 320.82 and 414.1 J.cm−2.day−1 at Ahvaz, BandarAbbas, and Kermanshah stations, respectively (in validation phase); although its error rates are significant compared with the SVM model, and substituting it for artificial intelligence-based models is not recommended. Validerad;2022;Nivå 2;2022-01-12 (johcin)

Measurements of the atmospheric concentration of polluting atomic mercury were performed using the differential absorption lidar (DIAL) technique in the Lintong district, about 35 km northeast of Xi&rsquo, an, the capital of the Shaanxi province, China. Concentrations ranging from 2 to 13 ng/m3 were observed. As uniquely enabled by the lidar technique, representative average concentrations, integrated over a considerable volume, were recorded and put in relation to weather conditions, and vertical concentration profiles were measured. Considerable local non-uniformities were also observed, which may indicate the presence of localized hot-spots in the area, possibly related to ancient tombs.

68 páginas, 1 mapa. En el presente trabajo, se muestran los resultados obtenidos en el marco del convenio específico entre el Instituto Geológico Minero y Metalúrgico (INGEMMET) y el Servicio Geológico de China (CGS: China Geological Survey), entre los años 2017 y 2018. El área de estudio corresponde principalmente al Segmento Lima. En los cuerpos plutónicos del segmento Lima (128 a 33 Ma), se pueden observar con claridad las variaciones litológicas laterales asociadas a la diferenciación magmática directa, varían de dioritas a monzogranitos. Esto indica un desarrollo continuo en los ensambles magmáticos o super unidades. Las estructuras internas de los cuerpos intrusivos más característicos se pueden observar en cuerpos de monzogranitos de las super unidades Puscao, Tiabaya y Pativilca, donde se puede observar zonas de enclaves máficos: dispersos, a manera de capas (seudo estratificado) y diques sin magmáticos, estructuras asociadas principalmente a mezcla de magma. Para comprender la distribución temporal y espacial de la población de cristales de las rocas plutónicas del Batolito de la Costa, en el segmento Lima, se generó una base de datos composicional con las principales características petrográficas de cada roca, con ella, se generaron diagramas binarios MINEA (Minerales Esenciales y Accesorios). Donde se pudo observar, que las mayores concentraciones de feldespato potásico (K) están asociadas a rocas de la super unidades Linga, Tiabaya y Santa Rosa, asociados al magmatismo de 83.6 a 72.1 Ma. Por la gran extensión del área de trabajo, afinidad litológica y rango de edad antes definida (61-90 Ma), la Super Unidad Santa Rosa fue agrupada con otras super unidades (La Mina, San Jerónimo, Puscao) y definida como Superemsamble Santa Rosa, esto para el presente trabajo. En el análisis geoquímico, los diagramas de elementos trazas y elementos de tierras raras muestras una evolución de magmas mantélicos a muy diferenciados. Los magmas mantélicos están asociados a rocas de la Super Unidad Patap y los magmas diferenciados están asociados al Superensamble Santa Rosa y Super Unidad Catahuasi. Las mayores anomalías de HFSE, como Th y U, muestran las rocas del Superensamble Santa Rosa y Super Unidad Linga. Esto quiere decir que son rocas diferenciadas y de gran energía. Las rocas de este segmento muestran anomalías negativas de Nb y Ta, típicas de magmatismo de arco andino. A medida que el magma evoluciona, se observa un dominio de anfíboles y granate en los elementos de tierras raras pesadas evidenciada por la anomalía negativa mostrada en Y e Yb. Este último se puede asociar a ocurrencias de Cu-Mo y Mo, debido a que el Mo está controlado por la anomalía de Y en el fundido. Durante el año 2018, se obtuvieron 59 nuevas edades isotópicas U-Pb, estas se realizaron sobre zircones en rocas ígneas, principalmente en rocas plutónicas. Los estudios isotópicos fueron realizados por el Servicio Geológico de China del Centro de Nanjing.

In order to solve the problems of low screening efficiency and resonance in the oscillating screen system of a new type of fresh bait feeding machine, The finite element calculation model is established in hypermesh. Under the finite element analysis of the model by ABAQUS software, the deformation diagram and stress value of the model are obtained. Through the harmonic response analysis, the excitation frequency parameters of the oscillating screen system are optimized, which can effectively solve the problems of low screening efficiency and resonance.

The effect of Zener-Hollomon (Z) parameter on quench sensitivity of 7085 aluminum alloy was investigated. With the increase of Z parameter from 2.67E10 to 4.79E16, quench sensitivity relative to hardness tends to decrease first and then increase, and it may be minimised in the range from 2.67E12 to 2.24E13. The reason was discussed mainly on the effect of Z parameter on recrystallization fraction, which changes the amount of nucleation sites of heterogeneous precipitation during slow quenching. Quench-induced η phase with little strengthening effect tends to form preferentially at grain boundaries and on the Al 3 Zr dispersoids with a size larger than about 23 nm in the recrystallized grains. The increase in the number of recrystallized grains can increase the amount of such grain boundaries and Al 3 Zr dispersoids, and therefore a larger amount of quench-induced phase; consequently, quench sensitivity increases.

In the concept of "One Belt One Road" opening to the west, the value of land port is constantly highlighting. Xi'an International Land Port is striving to build the largest international transit hub port and commercial logistics distribution center on the Silk Road economic belt. The role of Xi'an International Land Port is irreplaceable in the strategic mission of Shaanxi to build a new opening-up highland to the west. Based on the analysis of the development environment of Xi'an International Land Port, this paper finds out the problems existing in the development of Xi'an International Land Port, and puts forward some countermeasures to improve the development level, so that Xi'an international land port can truly become the cornerstone of Xi'an international trade, promote the construction of Greater Xi'an, promote the coordinated development of Xi'an and Guanzhong urban agglomerations, achieve regional coordination, build a "national central city" and a new business logistics engine.

Traditional methods of breeding soft-shell crabs mainly rely on manual identification, which has high costs regarding manpower and resources. Manual inspection may also interfere with crabs’ molting, causing molting failure, and possibly even death, which is costly and inefficient. This paper combines an improved YOLOv3 algorithm with an adaptive dark-channel defogging algorithm to realize the real-time detection of whether a swimming crab in a single-crab basket-culture system is molting. For learning more features, affine, rotation transformation and local occlusion are used to augment the training data to simulate the difficulty of identification caused by occlusion, in case molting may occur under distorted viewing conditions in real culture environments. A k-means++ clustering algorithm is used to obtain prior boxes matching the size of the carapace throughout the entire breeding cycle, and so improve the Intersection over Union (IOU). The identification network itself can have its network structure pruned and the non-maximum suppression function modified to increase rapidity and accuracy; the improved network can recognize and give early warning of the early stage of molting. The precision of the improved model in clean water reaches 100 %, and the running speed was 31 FPS. In turbid water where the prediction confidence is lower than the cut-in threshold of defogging algorithm set as 0.8, the precision of the improved model was over 91 %, and the speed can still maintain about 7 FPS.

The dynamic recrystallization behavior of 7085 aluminum alloy during hot compression at various temperatures (573–723 K) and strain rates (0.01–10 s −1 ) was studied by electron back scattered diffraction (EBSD), electro-probe microanalyzer (EPMA) and transmission electron microscopy (TEM). It is shown that dynamic recovery is the dominant softening mechanism at high Zener–Hollomon ( Z ) values, and dynamic recrystallization tends to appear at low Z values. Hot compression with ln Z =24.01 (723 K, 0.01 s −1 ) gives rise to the highest fraction of recrystallization of 10.2%. EBSD results show that the recrystallized grains are present near the original grain boundaries and exhibit similar orientation to the deformed grain. Strain-induced boundary migration is likely the mechanism for dynamic recrystallization. The low density of Al 3 Zr dispersoids near grain boundaries can make contribution to strain-induced boundary migration.

This publisher’s note corrects the author listing and a figure caption in Appl. Opt.57, 3481 (2018)APOPAI0003-693510.1364/AO.57.003481.

Understanding responses by changes in land use and land cover (LULC) and climate over the past decades on streamflow in the upper Blue Nile River basin is important for water management and water resource planning in the Nile basin at large. This study assesses the long-term trends of rainfall and streamflow and analyses the responses of steamflow to changes in LULC and climate in the upper Blue Nile River basin. Findings of the Mann-Kendall (MK) test indicate statistically insignificant increasing trends for basin-wide annual, monthly, and long rainy-season rainfall but no trend for the daily, short rainy-season, and dry season rainfall. The Pettitt test did not detect any jump point in basin-wide rainfall series, except for daily time series rainfall. The findings of the MK test for daily, monthly, annual, and seasonal streamflow showed a statistically significant increasing trend. Landsat satellite images for 1973, 1985, 1995, and 2010 were used for LULC change-detection analysis. The LULC change-detection findings indicate increases in cultivated land and decreases in forest coverage prior to 1995, but forest area increases after 1995 with the area of cultivated land that decreased. Statistically, forest coverage changed from 17.4% to 14.4%, by 12.2%, and by 15.6%, while cultivated land changed from 62.9% to 65.6%, by 67.5%, and by 63.9% from 1973 to 1985, in 1995, and in 2010, respectively. Results of hydrological modelling indicate that mean annual streamflow increased by 16.9% between the 1970s and 2000s due to the combined effects of LULC and climate change. Findings on the effects of LULC change on only streamflow indicate that surface runoff and base flow are affected and are attributed to the 5.1% reduction in forest coverage and a 4.6% increase in cultivated land areas. The effects of climate change only revealed that the increased rainfall intensity and number of extreme rainfall events from 1971 to 2010 significantly affected the surface runoff and base flow. Hydrological impacts by climate change are more significant as compared to the impacts of LULC change for streamflow of the upper Blue Nile River basin.

With the acceleration of industrialization in China, the output and transportation volume of hazardous chemical have increased dramatically. On the one hand, chemical has injected new vitality into the social and economic development. On the other hand, the safety of hazardous chemical has also been highlighted. According to statistics, hazardous chemical accidents in transportation links accounted for 35% of hazardous chemical accidents. Hazardous chemical transportation accident belongs to the low probability and serious consequence event. Once hazardous chemical accident occurs, it will cause great losses to people's lives, property and ecological environment. The hazardous chemical road transportation security question becomes the question which the people pay close attention to. In order to reduce hazardous chemical transportation accidents, we study the hazardous chemical transportation route optimization. In this paper, we propose an improved ant colony algorithm. The improved ant colony algorithm not only considers the transportation time and transportation risk, but also improves its algorithm settings. The improved algorithm is more suitable for optimizing the path of hazardous chemical. The experiments in this paper also verify the effectiveness and reliability of the improved algorithm.

New residential villages appeared in Shanghai as early as the 1920s, and by the 1930s, they were already an important part of the geography of residential life in the city. In this process, business capital, corporates, and local government consumed the original utopian space characterized by the symbols of equality, justice, hygiene, and health, while absorbing the idea of the ideal Garden City. This idea was adopted by the Chinese communist party and it was the symbol of the working class becoming the master of socialist society in the People’s Republic of China (PRC) and a radical break with the old capitalist city space. The authors use Lefebvre’s idea to analyze the consequences of the new residential villages for the production of social and physical space in Shanghai from 1920 to 1980.

A series of novel 1-arylpyrazolo[3,4-d]pyrimidine derivatives, containing an amide moiety, was synthesised by condensation of different acids with 1-(2,4-dichlorophenyl)-1H-pyrazolo[3,4-d]pyrimidin-4-amine. This intermediate was prepared from 5-amino-1-(2,4-dichlorophenyl)-1H-pyrazole-4-carbonitrile by condensation with triethyl orthoformate and then cyclisation with ammonium hydroxide solution in tetrahydrofuran at room temperature. In addition, the molecular structure of a 1-arylpyrazolo[3,4-d]pyrimidine containing an amide moiety was determined by single crystal X-ray diffraction.

The title compound, 5-(4-fluorophenyl)-N,N-dimethyl-7-(trifluoromethyl)pyrazolo[1,5-a]pyrimidine-3-carboxamide, has been synthesised by condensation of dimethylamine with 5-(4-fluorophenyl)-7-(trifluoromethyl)pyrazolo[1,5-a]pyrimidine-3-carboxylic acid. This intermediate was prepared from ethyl 5-amino-1H-pyrazole-4-carboxylate by cyclisation with 4,4,4-trifluoro-1-(4-fluorophenyl)butane-1,3-dione and then saponification with sodium hydroxide. The crystal structure of the title compound was determined. The compound possesses distinct effective inhibition on the proliferation of some cancer cell lines.

Based on O2O theory and O2O model, this paper analyzes on logistics distribution situation of catering enterprises on the self ordering platform and find out the existing problems. This paper also put forward some suggestions on the catering enterprises in the O2O mode of logistics distribution: with the help of the third party logistics to build new logistics mode of catering enterprises, implementation of distribution service system catering logistics standardization, strengthen the construction of logistics information system, improve the catering logistics laws and regulations, etc.

This study evaluated Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) product i.e. TRMM 3B42 data, using data from 52 rain gauge stations around the Meichuan watershed, which is a representative watershed of Poyang Lake basin in China. Both the latest Version 7 (V7) and previous Version 6 (V6) of TRMM 3B42 data were compared and evaluated for a 9-year period covering 2001–2005 and 2007–2010. The evaluations were conducted at different spatial (grid and watershed) and temporal (daily, monthly and annual) scales. For evaluation at grid scale, the Thiessen polygon method was used to transform pointed-based rain gauge data to areal precipitation at the same grid scale (0.25°) as TRMM 3B42 data. The results showed that there was little difference in performances of V6 and V7 TRMM 3B42 products. Overall, both V6 and V7 products slightly overestimated precipitation with a bias of 0.04. At daily scale, both V6 and V7 data were considered to be unreliable with larg...

Planning anthropomorphic robot hand for manufacturing waterproof glove, we adopt the geometric modeling method and develop a dexterous robot hand. This robot hand has powerful fingertip force and dexterous motion. This paper presents the design and experiments of this robot hand which has 7 actuated degrees of freedom. Each part of the robot hand has been established the geometric model. For acquiring the powerful force, the finger is driven by tendon, and the driving force from the actuators has been transmitted to the fingers by wire ropes in the arm. The prototype of this robot hand has been developed and tested. This experiment demonstrates that the robot hand can wear the glove efficiently and make accurate gestures which is the user expected. The application of this robot hand in the waterproof glove production line can save the physical labor.

A series of novel 1-arylpyrazolo[3,4-d]pyrimidine derivatives, containing an amide moiety, was synthesised by condensation of different acids with 1-(2,4-dichlorophenyl)-1H-pyrazolo[3,4-d]pyrimidin-4-amine. This intermediate was prepared from 5-amino-1-(2,4-dichlorophenyl)-1H-pyrazole-4-carbonitrile by condensation with triethyl orthoformate and then cyclisation with ammonium hydroxide solution in tetrahydrofuran at room temperature. In addition, the molecular structure of a 1-arylpyrazolo[3,4-d]pyrimidine containing an amide moiety was determined by single crystal X-ray diffraction.

Metal nanoparticles are well-known to exhibit a strong interaction with light, which have very important applications and one of them, recent years, is optical trapping of the metallic nanoparticles. Based on the principle of the optical trapping for metallic nanoparticles, in this paper, the gradient forces and the scattering forces in the optical trapping for gold-, silver- and copper-nanoparticles have been analyzed and calculated numerically. Typical power spectra for gold-, silver- and copper-nanoparticles have been obtained. It is shown from the calculation results that under what condition these metallic nanoparticles can be trapped, and the stability of the potential well for these metallic nanoparticles has been analyzed in order to know whether the well was deep enough for overcoming the gravity and Brownian motion.

The nonlinear optical susceptibility with inter-subband transitions between conduction band and valence band is theoretically calculated for CdSe/ZnS core-shell quantum dot (QD). Under the effective-mass approximation, the eigenenergy and wavefunction of electrons and holes have been calculated by solving stationary Schrödinger equation. The third-order nonlinear optical susceptibilities χ(3) of quadratic electro-optic effects (QEOE) have been also calculated in the case that spin-orbit splitting is considered.

Organophosphorus chemistry is organized around σ 3 and σ 4 phosphorus compounds and their derivatives. For a long time, this represented the core of phosphorus chemistry and, still today, the bulk of the work on phosphorus concerns this domain. Starting in the 1960s, a new realm of P-chemistry started to emerge. It concerns σ 1 and σ 2 phosphorus compounds. The aim of this concise review is to summarize the main advances in this new field.

The morphological and physico-chemical properties of four pedons representing the major aeolian sandy soils in the arid and semi-arid regions of China were studied for their potential for amelioration and utilization. The aeolian sandy soils of this area show wide variation in their morphological and physico-chemical properties as a result of differences in mean annual precipitation, parent material, vegetation and topography where they are found. The characteristics of and differences among aeolian sandy soils are described in detail. The processes forming these sandy soils are characterized by: (1) fine particle accumulation; (2) crust formation; (3) organic matter accumulation; (4) soil water physical property changes; and (5) total chemical composition changes. The four pedons are classified into four taxonomic groups, based on soil genetic theory. They are Hyperaripsamments, Aripsamments, Semiaripsamments, and Ustpsamments.

GaN intermedial layers grown under different pressures are inserted between GaN epilayers and AlN/Si(111) substrates. In situ optical reflectivity measurements show that a transition from the three-dimensional (3D) mode to the 2D one occurs during the GaN epilayer growth when a higher growth pressure is used during the preceding GaN intermedial layer growth, and an improvement of the crystalline quality of GaN epilayer will be made. Combining the in situ reflectivity and transmission electron microscopy (TEM) measurements, it is suggested that the lateral growth at the transition of growth mode is favourable for bending of dislocation lines, thus reducing the density of threading dislocations in the epilayer.

The spatial and temporal patterns of pedogenesis on stabilized dunes at Shapotou, northwestern China, were studied on the time sequences of 0, 18, 35 and 43 years. The spatial pattern of soil formation was estimated by measuring the thickness of accumulated sand fractions on the stabilized dune surface and by analyzing the characteristics and properties of soil. The results showed that the environment of soil formation and circulation of soil material were influenced in the processes of shifting-sand fixation, and the mean soil particle size changed from >0.2 to

The spatial and temporal patterns of soil crust formation on stabilized dunes at Shapotou, northwestern China, were studied on a time sequence of 0, 18, 35, and 43 years. The spatial pattern of soil formation was estimated by measuring the thickness of accumulated sand fractions on the stabilized dune surface and by analyzing the particle size distribution of soil crust. The results showed that the materials forming the embryonic crusts did not come entirely from atmospheric dustfall, but more likely originated from the deflation process of shifting sand and were related to the characteristics of shifting sand particles. Irrespective of the age, all crusts contained a relatively large proportion of 0.01-0.05 mm particles, suggesting that the 0.01-0.05 mm particles provide a material basis and are a prerequisite to the formation of soil crusts. The formation of crust was a sorting and accumulation process of 0.01-0.05 mm particles. Simultaneously, the formation of stable soil crust apparently tended to be ...

Current computational modeling methods for simulating blast and ejecta in soils resulting from the detonation of buried explosives rely heavily on continuum approaches such as Arbitrary Lagrangian-Eulerian (ALE) and pure Eulerian shock-physics techniques. These methods approximate the soil as a Lagrangian solid continuum when deforming (but not flowing) or an Eulerian non-Newtonian fluid continuum when deforming and flowing at high strain rates. These two extremes do not properly account for the transition from solid to fluid-like behavior and vice versa in soil, nor properly address advection of internal state variables and fabric tensors in the Eulerian approaches. To address these deficiencies on the modeling side, we are developing a multiscale multiphase hybrid Lagrangian particle-continuum computational approach, in conjunction with coordinated laboratory experiments for parameter calibration and model validation. This paper provides an overview of the research approach and current progress for this Office of Naval Research (ONR) Multidisciplinary University Research Initiative (MURI) project. © The Society for Experimental Mechanics, Inc. 2014.

Soil is an important factor in regional and global carbon budgets because it serves as a reservoir of large amount of organic carbon. In our study, using remote sensing data of different periods we analyzed the development and reversion of desertification in China, calculated the variations of organic carbon contents of the desertified lands in China. The results showed that the total storage of organic carbon in 0–50 cm soil layer of the desertified lands is 855 Mt. In recent 40 yr, the total CO 2 amount released by land desertification processes to the atmosphere was 150 Mt, while the CO 2 amount sequestered by desertification reversing processes corresponded to 59 Mt C. Hence, the net CO 2 amount released from desertified lands of China corresponded to 91 Mt C, about 68.42% of the 133 Mt C of annual CO 2 release in the global temperate and frigid zones. Simultaneously, it indicated that CO 2 amount sequestered by desertification reversing processes in desertified land had greater potential than the other soils.

A method to evaluate some Fourier integrals is extended from two-dimensional (2-D) and three dimensional (3-D) spaces ton-dimensional (n-D) space, which are often used in the elasticity theory of dislocations in quasicrystals. Some key formulae have been given.

Wearable exoskeleton robot is a kind of humanoid service robot to help the elderly and the patients with walking dysfunction, it is also an effective medical rehabilitation method to help patients who have walking disorders due to central neural system damage. This paper focuses on the flexible mechanism design of wearable lower limb exoskeleton robot. A wearable exoskeleton robot prototype was developed which can assist human walking. This paper analyzes the role of the major joints of walking human by experimental studies based on bionic design methods from human anatomy and bone surgery. We first analyze parameters of joint movements in a gait cycle, then we design a preliminary bionic model, finally we proposed a control strategy including a pair of electric crutches for the exoskeleton robot.

By using a small culture dish located above a large-sized closed dish with soil samples to trap emissions as well as applying multivariate analysis methods, the influence of soil properties on ammonia volatilization and their correlation was studied. The results showed that the ammonia volatilization rates were positively correlated with the soil pH, CaCO3, and total salt contents but negatively correlated with the organic matter content, CEC, and clay content. Of the three negative correlation factors, the CEC was most highly correlated with ammonia volatilization, while among the three positive correlation factors, the pH predominated. These results enabled to assess the magnitude of ammonia volatilization from soils. According to the correlation equation of ammonia volatilization versus pH and CEC, the potential of ammonia volatilization of some soils in China was determined and the soils were divided into four groups. It was concluded that by increasing the application rate of organic matter ...

A simple method for solving Cauchy’s problem of wave equations in higher space dimensions with initial condition of separated variables, has been given by using D’Alembert’s formula and some examples have been shown.

The Max’s equation of self-focusing in laser-plasma interaction due to the pondermotive force has been discussed and its physical meaning of the assumption has been predicted. The characteristics of selffocusing due to the pondermotive force with different initial situations have been analyzed through the numerical calculation.