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Agro-pastoral ecotone of northern China is the prominent area for agricultural production, but it is also the most typical ecological fragile area with frequent drought disasters. Taking Yulin City at Shaanxi Province in China as the case area, the paper aims to investigate the spatio-temporal changes of agricultural vulnerability to drought in China's agro-pastoral ecotone in the period 2000 to 2020. The results show that: 1) the agricultural vulnerability to drought in Yulin City has shifted from high vulnerability in the period 2000–2010 to low vulnerability in the period 2011–2020. 2) There exist obvious spatio-temporal differences of the agricultural vulnerability to drought in Yulin City during the research period. 3) Four sensitive events and 14 resilient events were identified in the research and the crops of Yulin had become more resilient to drought. Finally, the paper put forward with policy implications to make adaptive strategies of agriculture to climate change in China's agro-pastoral ecotone in the future, e.g., carrying out agricultural zoning based on agricultural production conditions, intensifying the construction of disaster prevention and relief system, and integrating with modern agricultural technology to develop new type agriculture. [ABSTRACT FROM AUTHOR]

Based on the greening and low interference disposal requirements of coal gangue in high-yield and high-efficiency mines in Inner Mongolia and Shaanxi, and by integrating the existing theories and technologies such as underground filling technology of coal gangue, mine yellow mud grouting technology, and the evolution law of mining overburden fractures, a technology of filling goaf with coal gangue slurry for green disposal of coal gangue is proposed. The principle and technical framework of the technology of filling goaf with coal gangue slurry are clarified. This paper expounds on the technological process of technology of filling goaf with coal gangue slurry, establishes three types of slurry filling systems, such as centralized ground layout, ground and underground coordinated layout, and centralized underground layout, and constructs three slurry filling methods, including low-level grouting, adjacent level grouting, and high-level grouting, forming seven kinds of technology models of filling goaf with coal gangue slurry, including ground centralized pulping + high-level grouting, ground centralized pulping + adjacent grouting, ground centralized pulping + low level grouting, ground and underground coordinated pulping + adjacent grouting, ground and underground coordinated pulping + low level grouting, underground centralized pulping + adjacent grouting, and underground centralized pulping + low level grouting, and gives the selection process of technology models of filling goaf with coal gangue slurry. Based on the different conditions and requirements of Haidaze Coal Mine and Huangling No. 2 Coal Mine, engineering tests were carried out on two different technology modes, namely, ground and underground coordinated pulping + low level grouting and ground and underground coordinated pulping + adjacent grouting, based on simulation tests of low level grouting and adjacent grouting. The tests prove the feasibility of filling goaf with coal gangue slurry and explore the way for the theoretical research of the technology of filling goaf with coal gangue slurry and greening and low interference disposal of coal gangue. [ABSTRACT FROM AUTHOR]

As an important resource for human survival, soil plays an important role in maintaining productivity, environmental quality, animal and plant health, etc. Soil quality evaluation, as a decision-making tool to improve understanding of soil quality, can effectively indicate soil status. Mu Us sandy land of Daji Khan in northern Shaanxi Province is one of the serious desertification areas in China. The phenomenon of soil erosion and ecological deterioration is extremely serious. Therefore, it is urgent to strengthen to pay attention to the research of Mu Us sandy land, to help the restoration of damaged soil, and to build a powerful soil ecosystem. In this paper, the soil quality in the process of development and utilization of the Mu Us sandy land was evaluated based on fuzzy sets for the purpose of sustainable utilization of compound soil. Based on soil structure and soil fertility, 16 evaluation indexes of soil quality in Mu Us sandy land were screened, and then the evaluation index system of soil quality was constructed. The fuzzy multi-objective decision-making model based on fuzzy sets was used to comprehensively evaluate the soil quality from 2013 to 2019. We calculated that the year-on-year growth rates of soil quality from 2013 to 2019 are 13.56, 0.16, 12.81, 33.84, 9.68, and 14.80%, respectively. The results showed that the overall soil quality in the study area showed a trend of increasing year by year, and the year-on-year increase was the largest in 2017. Meanwhile, the reasons for the sudden increase in soil quality in typical years were analyzed. The results showed that the dominant factor of this phenomenon was the comprehensive influence of soil fertility. Furthermore, the relationship between soil fertility and cultivated horizon in typical years was analyzed one by one, and the specific factors affecting soil fertility were discussed. [ABSTRACT FROM AUTHOR]

Analyzing the seepage and stability analysis of embankment dams built on deep overburden layers is an essential aspect of dam design and operation and is of significance to ensure the safe and effective operation of geotechnical and hydraulic structures in reservoir sites. However, in most existing studies, the seepage and dam slope stability were analyzed separately without considering the interaction between the two fields; thus, the actual operating state of the dam could not be accurately reflected. In this paper, an embankment dam located in Yulin, Shaanxi Province, China, built on a deep overburden layer, was selected as a case study for illustration. Considering the hydrogeological and engineering design information of this project, a three-dimensional fine finite element model reflecting the main characteristics of the reservoir site was established. COMSOL Multiphysics software, which is particularly suitable for multifield coupling calculations, was used to conduct a multifield coupling analysis of the safety state of embankment dams on deep overburden layers by modifying and customizing the porous media and subsurface flow module and solid mechanics module. The method to solve the multifield coupling problem was clarified. Notably, the proposed coupling model involved many parameters, which might introduce uncertainties into the model, thereby requiring considerable work for calibration. Therefore, the Morris method was used to identify the sensitivity of the coupled model parameters to the output results. The results show that the established multifield coupling model can effectively address the seepage and stability problems of embankment dams on deep overburden layers, and the dam can safely operate under the existing design scheme. Even under the condition of a magnitude VIII earthquake at the check flood level, the dam does not experience seepage and slope failure. The safety factor of sliding failure of the dam slope is mainly influenced by the internal friction of saturated soil (φs), material cohesion (c), internal friction of unsaturated soil (φu), soil density (ρs) and Poisson's ratio (ν), while the influence of the seepage parameters is generally small. The methodology and results derived from this study can provide technical support and reference to evaluate the safety in terms of the seepage and anti-sliding stability of similar projects. [ABSTRACT FROM AUTHOR]

A woman's crown made of fine gilt bronze with refined glass inlay work was excavated from a Sui-Tang tomb called Kunlun M2 in Xi'an, Shaanxi Province, China. Very few female crowns and crown ornaments have been excavated in China thus far, and there has been a lack of systematic research into the technologies used to manufacture them. Importantly, this paper uses the M2 crown to investigate its surface inlays and overall shape, then conducts a comparative analysis of women's crown ornaments of the same type, providing a reference for study of the crown. Non-invasive and micro-destructive analysis including optical microscopy (OM), optical coherence tomography (OCT), micro X-ray fluorescence imagery (XRF), and Raman spectroscopy were applied. These identified the crown's inlays as potash-lime glass, composed mainly of the raw materials: vein quartz or quartzite with potassium nitrate as flux. The inlays were sintered before embedding into gilt copper wire filigree. In comparison to the composition proportions in other ancient potash-lime glass, there is no specific percentage of the raw materials in Chinese potash-lime glass, where the ingredients were likely determined by the experience of the craftsman. Compared with existing research on other crowns and their inlays, this study speculates that the crown dates from the Sui dynasty (581–618) or early Tang dynasty (618–649), was made locally by Chinese craftsmen and belonged to the wife of a high official. [ABSTRACT FROM AUTHOR]

The effect of lateral deformation on subgrade settlement is often ignored. This paper discusses this effect under different constraint conditions. Compression tests of typical Q2 remoulded loess from Shaanxi Province, China, were conducted under different confining pressures using a self-developed three-dimensional loading test device. The vertical and lateral deformation characteristics of loess samples were analysed, and a model of lateral strain in subgrade soil was derived. Then, a model of total subgrade settlement with consideration of lateral deformation was established based on the equal volume concept. The stratified summation calculation formula was also revised, and correction coefficients under different constraints are given. The results show that the accuracy of the revised method is positively correlated with the number of lateral constraints. The correction coefficient can reflect the influence of different subgrade constraints. Importantly, the modified model was verified by field measurements and found to be more accurate than the stratified summation method. These results help to understand the influence of lateral deformation on total settlement and the mechanism of subgrade settlement. [ABSTRACT FROM AUTHOR]

Alternaria leaf blotch, and rust are two common types of apple leaf diseases that severely affect apple yield. A timely and effective detection of apple leaf diseases is crucial for ensuring the healthy development of the apple industry. In general, these diseases are inspected by experienced experts one by one. This is a time-consuming task with unstable precision. Therefore, in this paper, we proposed a LOW-COST, STABLE, HIGH precision apple leaf diseases identification method. This is achieved by employing MobileNet model. Firstly, comparing with general deep learning model, it is a LOW-COST model because it can be easily deployed on mobile devices. Secondly, instead of experienced experts, everyone can finish the apple leaf diseases inspection STABLELY by the help of our algorithm. Thirdly, the precision of MobileNet is nearly the same with existing complicated deep learning models. Finally, in order to demonstrated the effectiveness of our proposed method, several experiments have been carried out for apple leaf diseases identification. We have compared the efficiency and precision with the famous CNN models: i.e. ResNet152 and InceptionV3. Here, the apple disease datasets (including classes: Alternaria leaf blotch and rust leaf) were collected by the agriculture experts in Shaanxi Province, China. [ABSTRACT FROM AUTHOR]

During the construction of tunnels in the central and western regions of China, diorite is frequently affected by vibration, blasting and water which will lead to the questions of the quality and operational safety of project. However, there are few studies on the dynamic characteristics of diorite under the action of dry–wet cycles. Therefore, this paper selected the gray–green altered diorite from Ning shan County, Shaanxi Province, China, mainly composed of plagioclase, and used the Slit Hopkinson pressure bar (SHPB) to study the effect of dry–wet cycle on the dynamic characteristics of Diorite. The test results show that the strength decay rate of the peak strength of diorite is the maximum under 1–3 dry–wet cycles, then decreases gradually. The dynamic elastic modulus of diorite dropped by 35.02% after three dry–wet cycles, accounting for 98.45% of the total attenuation. Compared the test result of three dry–wet cycles, the decrease volumes of the stress growth rate of diorite are the largest after six dry–wet cycles. Because of the actions of the dry–wet cycles, the growth rate of the rapid growth stage of the reflected energy–time history curve reduces and the growth rate of the rapid growth stage of the transmitted energy–time history curve improves. Under the action of the dry–wet cycles, the dissipation energy ratio gradually decreases, and the decrease of energy consumption density follows a negative exponential function relationship. Under the action of multiple dry–wet cycles, the tension and compression stress frequently change between the particles of rock, resulting in a significant increase of micro-cracks and an obvious degradation effect on the dynamical properties of diorite. [ABSTRACT FROM AUTHOR]

Silo-cave is a unique human habitation form on the Loess Plateau in northern China, which consists of an excavated 6–7 m deep pit as the courtyard and cave dwellings in the surrounding four walls. This architecture has had a history of more than 7000 years, and yet such "living fossils for the history of dwellings" are now facing great crises and challenges during rapid social and economic development. In this paper, remote sensing and GIS techniques are used to comprehensively and systematically investigate the spatial distributions and morphological characteristics of silo-caves at both the macro and micro scales. The research shows that silo-cave villages are mainly distributed in economically underdeveloped areas, such as West Henan (Yuxi), South Shanxi (Jinnan), Central Shaanxi (Guanzhong), and East Gansu (Longdong). The morphological evolution patterns of typical silo-cave villages are identified, including: (1) retaining the periphery and rebuilding the inner parts of the villages, (2) retaining the inner parts and expanding the periphery of the villages, and (3) rebuilding the inner parts and expanding the periphery of the villages. These patterns are demonstrated to be influenced by many factors, including landforms, traffic conditions, economic development, population growth, and administrative division adjustment. Sustainable development of these traditional silo-cave villages relies on administrative policy and planning, people's awareness of cultural heritage protection, culture inheritance, industrial transformation, and public services. [ABSTRACT FROM AUTHOR]