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Interferometric Synthetic Aperture Radar (InSAR) is a novel method of ground observation, which is widely used in fields such as surface deformation monitoring due to the fact that it is unrestricted of day and night, as well as cloud and rain. However, due to measurement errors, InSAR technology still has some limitations, especially in the densely vegetated southwest mountainous areas. Time series InSAR, such as SBAS-InSAR receives insufficient observation points, making it difficult to carry out deformation monitoring in mountainous areas. In response to the above issues, this paper considers the atmospheric characteristics of the southwest mountainous areas and designs an improved SBAS-InSAR method to optimize the interferometric phase. The Lijiang-Shangrila Railway is an electrified railway connecting Lijiang City and Shangri-La in Diqing Tibetan Autonomous Prefecture in Yunnan Province. It is an important component of the Yunnan Tibet Railway in the Western Railway Network. In order to ensure the safety and stability of the Lijiang-Shangrila Railway and verify the availability of the above method, this paper takes a certain section along the Lijiang-Shangrila Railway as the experimental area, uses archived SAR data to estimate historical surface deformation, calculates the historical time series deformation of the target area for nearly six and a half years (May 16, 2015 to December 10, 2021), and analyzes their influence range, deformation factors, change patterns, and other information. Finally, the improved SBAS InSAR method proposed in this article is compared with conventional InSAR method, which fully demonstrates the superiority of the proposed method. [ABSTRACT FROM AUTHOR]

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Much has been written about how digital technologies transformed contemporary festivals, yet the festival participants' perceptions and experiences are less examined. Understanding mediated festivals as events of intertwined mediation processes, this paper explores the perception and practices of mediated festivals in contemporary China. We conducted semi-structured interviews with 13 Chinese young people to understand their motivations and experiences of festival participation. The paper finds that emerging mediated festivals provide a space for individuals to explore their interests. Further, mediated festivals are perceived as a liberating force for young people through choice-making and self-presentation in convivial and hybrid festival environments. Developing Dayan and Katz's conception of 'media events', we argue that contemporary Chinese mediated festivals can be understood as 'my events' through hybrid and networked self-representations. Our study contributes to understanding the Chinese mediated festivals, emphasizing how networked individuals (re)negotiate the festival production. [ABSTRACT FROM AUTHOR]

Copyright of Tourism Tribune / Lvyou Xuekan is the property of Tourism Institute of Beijing Union University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of China Tourism Research is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Qinghai-Tibet Plateau (QTP) is the most unique region of human-land relations, and its main factor is population. By building a population and space dataset of the QTP at the township level from 1982 to 2017, this paper presents the pattern evolvement and regional distribution characteristics of township-level population in the QTP in detail for the first time. By using Geodetector method to analyze the influencing factors of township-level population change in the QTP, this paper provides scientific foundations for studying the Third Pole, ecological environment protection of the QTP, and human-land relations. The conclusions are as follows: 1) The population spatial distribution is not balanced at the township level, presents the regional differentiation characteristics of 'dense in southeast and sparse in northwest' along the 'Qilian-Jilong Line', and demonstrates the phenomenon of population center of gravity moving to the hinterland of the plateau at an accelerated speed; 2) The township-level population develops in a decentralized trend in general, and the cold- and hot-spot distribution of population has prominent spatial distribution characteristics. The population hot spots are concentrated in the surrounding areas of Xining, Golmud, Hotan and Lijiang; 3) The population of the QTP is increasing, and the inter-annual change of township population has a relatively stable regional regularity; 4) The level of per capita income is the leading factor in the change of township population, and its effect intensity is increasing continuously. The relative effect intensity of urbanization level and location conditions on population change has decreased significantly after 2000. The adaptability of living environment, such as topography and climate, has little influence on population change. [ABSTRACT FROM AUTHOR]

The Dongba manuscripts are a unique primitive pictographic writing system that originated among the Naxi people of Lijiang, China, boasting over a thousand years of history. The uniqueness of the Dongba manuscripts stems from their pronounced pictorial and ideographic characteristics. However, the digital preservation and inheritance of Dongba manu manuscripts face multiple challenges, including extracting its rich semantic information, recognizing individual characters, retrieving Dongba manuscripts, and automatically interpreting the meanings of Dongba manuscripts. Developing efficient Dongba character detection technology has become a key research focus, wherein establishing a standardized Dongba detection dataset is crucial for training and evaluating techniques. In this study, we have created a comprehensive Dongba manuscripts detection dataset covering various commonly used Dongba characters and vocabularies. Additionally, we propose a model named STEF. Firstly, the Swin Transformer extracts the complex structures and diverse shapes of Dongba manuscripts' features. Then, by introducing a Feature Pyramid Enhancement Module, features of different sizes are cascaded to preserve multi-scale information. Subsequently, all features are fused in a FUSION module, resulting in features of various Dongba manuscript styles. Each pixel's binarisation threshold is dynamically adjusted through a differentiable binarisation operation, accurately distinguishing between foreground Dongba manuscripts and background. Lastly, deformable convolution is introduced, allowing the model to dynamically adjust the convolution kernel's size and shape based on the Dongba manuscripts' size, thereby better capturing the detailed information of Dongba characters of different sizes. Experimental results show that STEF achieves a recall rate of 88.88%, a precision rate of 88.65%, and an F-measure of 88.76%, outperforming other text detection algorithms. Visualization experiments demonstrate that STEF performs well in detecting Dongba manuscripts of various sizes, shapes, and styles, especially in blurred handwriting and complex backgrounds. [ABSTRACT FROM AUTHOR]

Background: Gene flow is crucial for enhancing economic traits of livestock. In China, breeders have used hybridization strategies for decades to improve livestock performance. Here, we performed whole-genome sequencing of a native Chinese Lijiang pig (LJP) breed. By integrating previously published data, we explored the genetic structure and introgression of genetic components from commercial European pigs (EP) into the LJP, and examined the impact of this introgression on phenotypic traits. Results: Our analysis revealed significant introgression of EP breeds into the LJP and other domestic pig breeds in China. Using a haplotype-based approach, we quantified introgression levels and compared EP to LJP and other Chinese domestic pigs. The results show that EP introgression is widely prevalent in Chinese domestic pigs, although there are significant differences between breeds. We propose that LJP could potentially act as a mediator for the transmission of EP haplotypes. We also examined the correlation between EP introgression and the number of thoracic vertebrae in LJP and identified VRTN and STUM as candidate genes for this trait. Conclusions: Our study provides evidence of introgressed European haplotypes in the LJP breed and describes the potential role of EP introgression on phenotypic changes of this indigenous breed. [ABSTRACT FROM AUTHOR]

The 2021 Yangbi Ms 6.4 earthquake in Yunnan, China, occurred in an area where the Global Positioning System (GPS) geodetic observations are particularly intensive. Based on a detailed retrospective analysis of the GPS observations of about 133 stations distributed in the proximately 400 km × 400 km region that contains the area affected by the earthquake., we obtain a high-resolution GPS velocity field and strain rate field and then derive the present-day slip rates of major faults in the region with the commonly used half-space elastic dislocation model and constraints from the GPS velocity field. Furthermore, by calculating the seismic moment accumulation and release and deficit rates in the main fault segments and combining with the distribution characteristics of small earthquakes, we evaluate the regional seismic risk. The results show that (1) there was a localized prominent strain accumulation rate around the seismogenic area of the impending Yangbi Ms 6.4 earthquake, although this was not the only area with a prominent strain rate in the whole region. (2) The seismogenic area of the earthquake was just located where the strain direction was deflected, which, together with the localized outstanding maximum shear strain and dilatation rates, provides us with important hints to determine the potential areas of future strong earthquakes. (3) Of all the seismogenic fault segments with relatively high potentials, judged using the elapsed time of historical earthquakes and effective strain accumulation rate, the middle section of the Weixi–Qiaohou fault has a higher earthquake risk than the southern section, the Midu–Binchuan section of the Chenghai fault has a higher risk than the Yongsheng section and the Jianchuan section of the Jianchuan–Qiaohou–Lijiang–Xiaojinhe fault has a higher risk than the Lijiang section. [ABSTRACT FROM AUTHOR]

On 2 January 2022, an earthquake of Ms 5.5 occurred in Ninglang County, Lijiang City, the earthquake-prone area of northwestern Yunnan. Whether this earthquake caused significant deformation and thermal anomalies and whether there is a relationship between them needs further investigation. Currently, multi-source remote sensing technology has become a powerful tool for long-time-series monitoring of earthquakes and active ruptures which mainly focuses on single crustal deformation and thermal anomaly. This study aims to reveal the crustal deformation and thermal anomaly characteristics of the Ninglang earthquake by using both Interferometric Synthetic Aperture Radar (InSAR) and Robust Satellite Techniques (RST). First, Sentinel-1A satellite SAR data were selected to obtain the coseismic deformation field based on Differential InSAR (D-InSAR), and the Small Baseline Set InSAR (SBAS-InSAR) technique was exploited to invert the pre- and post-earthquake displacement sequences. Then, RST was used to extract the thermal anomalies before and after the earthquake by using Moderate Resolution Imaging Spectroradiometer Land Surface Temperature (MODIS LST). The results indicate that the seismic crustal deformation is dominated by subsidence, with 23 thermal anomalies before and after the earthquake. It is speculated that the Yongning Fault in the deformation area is the main seismogenic fault of the Ninglang earthquake, which is dominated by positive fault dip-slip motion. Meanwhile, the seismic fault system composed of NE- and NW-oriented faults is an important factor in the formation of thermal anomalies, which are accompanied by changes in stress at different stages before and after the earthquake. Moreover, the crustal deformation and seismic thermal anomalies are correlated in time and space, and the active rupture activities in the region produce deformation accompanied by changes in thermal radiation. This study provides clues from remote sensing observations for analyzing the Ninglang earthquake and provides a reference for the joint application of InSAR and RST for earthquake monitoring. [ABSTRACT FROM AUTHOR]

The emergency response actions against an impending barrier lake breach flood involve multiple social and engineering approaches, such as evacuating the affected people downstream, lowering the breach opening by excavating a diversion channel, and regulating the downstream hydraulic structures if present. Analytical evaluation of the breach flood under different scenarios of emergency mitigation is crucial for a rational decision when a rescue plan is being made. This study reviews the emergency responses undertaken for the "11.03" Baige barrier lake that occurred in the Jinsha River of China in 2018, which involved the evacuation of 27,500 downstream people in the Shangri-La and Lijiang tourist attraction areas and the engineering measures by excavating a diversion channel and treating the two existing dams. The numerical model for dam breach and flood routing analysis performed by the computer programs DB-IWHR and Hec-Ras allowed quantitative risk assessments for various scenarios of mitigation approaches. The results showed that the excavation of the 15-m-deep diversion channel reduced the peak flood discharge from 39,580 to 31,000 m3/s. The demolition of the Suwalong cofferdam avoided a cascade dam failure that would have created a peak flood of 22,841 m3/s, resulting in a 2.25-m-high additional inundation on an area of 1.13 × 105 m2. The numerical assessment confirms the substantial reduction in the social and economic impact achieved by pre-emptying the Liyuan Hydropower Station, which avoided a sustained 10-h spillway discharge of 12,231 m3/s. [ABSTRACT FROM AUTHOR]

We are running a wide field photometric survey under the collaboration between Yunnan Observatories and Hong Kong Astronomical Society with a Centurion 18‐inch telescope at the Lijiang station of Yunnan Observatories, China. Its scientific goals are discovering new transiting exoplanetary systems and other types of variable stars, and studying asteroids of the solar system. The survey was designed to monitor several fixed sky areas through time series photometry with short cadences. Since 2016, numerous observing data have been accumulated and reduced by means of dedicated pipelines to deliver the light curves for tens of thousands objects, which are cross‐matched through the Carlsberg Meridian Catalog 15 or USNO‐B1.0 catalog. Systematic errors and trends that existed in the raw photometric results are simulated through selected reference stars and then removed to improve signal‐to‐noise ratios of the light curves, which is crucial to detect weak signals like exoplanet transits and other variable stars of low amplitudes in brightness variations. The final data products own the photometric precision better than 0.01 magnitude for stars brighter than 13.8 magnitude in the V band. By means of generalized Lomb–Scargle, phase dispersion minimization, and box‐fitting least squares techniques, we have already identified about a thousand of variable stars from the survey, including transiting exoplanet candidates, spotted stars, eclipsing binaries, pulsating stars, and so on. In addition, we have also captured around a thousand of asteroids of the solar system in the survey fields and produced their light curves due to spins. [ABSTRACT FROM AUTHOR]

Monitoring groundwater storage changes is one of the most important topics in the sustainable management of groundwater resources. The sensitivity of gravity to changes in mass allows one to obtain an estimate of groundwater storage changes through gravity observations. The karst aquifer in the Black Dragon Pool is the main water resource for Lijiang City. As a result of overexploitation of groundwater resources, the groundwater level has declined since 2008, although it started to rise with the implementation of water resource management practices in 2017. In this study, we assess the local groundwater storage changes in a karst aquifer by using a more than 4-year record (2017–2021) of the superconducting gravimeter OSG-066 located at the Lijiang station. Firstly, the records were preprocessed by calibrating the data and removing interferences such as earthquakes, spikes, and steps. The gravity effects of the tides, atmosphere, and polar motion and the linear trend term were then subtracted to obtain the preliminary residual gravity signal. After correcting for the effect of terrestrial water storage and land uplifting, the final residual gravity signal was obtained, which was analyzed by comparison with the groundwater level change. We find that the topographic effect on gravity must be considered due to the complex topography around the Lijiang Basin. We note that the amplitude of residual gravity is dominated by the groundwater level change in the Black Dragon Pool, with a phase lag between the final residual gravity and groundwater level change. The final residual gravity clearly displays characteristics of seasonality and fluctuation, with variable amplitude. From the joint analysis of gravity records and well and model data, we demonstrate that both the residual gravity and groundwater level exhibit a downward trend after 2018. At the same time, however, gravity observation reflects the effectiveness of water resource management practices implemented in 2017. [ABSTRACT FROM AUTHOR]

Understanding the spatial and temporal distribution patterns of fire is of ecological, social and economic importance. The purpose of this study is to examine the spatial distribution of high fire risk using machine learning algorithms and early warning weather in high-risk areas. Take the satellite monitored fire point data in Yunnan Province during 2015–2019 as an example. The spatial distribution law of high-density parts is found using hierarchical density-based spatial clustering of applications with noise (HDBSCAN) algorithm, and the correlation degree analysis of high-density fire areas based on clustering and annual mean meteorological factors is carried out using grey correlation analysis (GCA) method. Results illustrates that within five years, fires frequently occurred in the seven regions of Wenshan Zhuang and Miao Autonomous Prefecture, Honghe Hani and Yi Autonomous Prefecture, Lijiang City, Pu'er City, and Xishuangbanna Dai Autonomous Prefecture. Among them, the fire in Lijiang had the greatest relationship with precipitation, Pu'er and Xishuangbanna had the greatest correlation with temperature, and Honghe Hani and Wenshan Zhuang were most affected by wind speed. This article acclaims fire prevention in key periods, key areas, key weather and reinforces the protection of transmission lines in the risk area. [ABSTRACT FROM AUTHOR]