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LTE-M vehicle-ground wireless system based on 1.8 GHz dedicated frequency band is superior to WLAN in terms of security, delay, communication quality, coverage, adaptability to higher speed and interconnection. It has become the standard configuration for carrying CBTC service of signaling system. This paper analyzes the key elements in different stages of LTE-M replacing WLAN without affecting the operation of existing lines, and puts forward the vehicle ground wireless system renovation scheme of urban rail transit signaling system, which provides reference for similar projects. [ABSTRACT FROM AUTHOR]

The analysis of the spatial connection and structural characteristics evolution of the railway passenger transport network in Chengdu-Chongqing Economic Circle is of great significance to the future network construction and layout optimization. This paper constructs the railway passenger transport network of Chengdu-Chongqing Economic Circle based on the 46 863 617 railway passenger transport data, and uses GIS spatial analysis and social network analysis methods to analyze the space-time evolution of railway passenger transport links, the evolution of structure characteristics and the impact of network structure on economy and population in continuous time series. The results show that the polarization of railway passenger transport links in Chengdu Chongqing Economic Circle is obvious, and the passenger transport flow is mainly concentrated in Chengdu, followed by Mianyang, the main districts of Chongqing and Deyang, and other cities account for less than 20% of the passenger transport flow. The density of railway passenger transport network in Chengdu-Chongqing Economic Circle is increasing year by year, but it is still at a low level. The railway passenger transport network has a low average path length and a high average clustering coefficient, and it is characterized by a small world. The degree centrality and betweenness centrality of Chengdu and the main districts of Chongqing are far more than those of other cities. The accessibility of railway passenger transport in Chengdu-Chongqing Economic Circle is largely due to the intermediary role of Chengdu and the main districts of Chongqing. There is no railway passenger transport connection between most cities. The degree centrality, proximity centrality and intermediate centrality have positive effects on GDP, and pass the 1% significance level test. The degree centrality and intermediate centrality have negative impacts on the population, and pass the significance level tests of 5% and 10% respectively. Cities in the central position are not conducive to the permanent residence of the population. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office 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.)

For the location-routing problem of medical waste treatment centers, this paper proposed a multi-objective optimization model considering the public risk. Firstly, from the perspective of the government, the public and the processing center contractor, this paper established the mathematical model which simultaneously considered the operation cost, public risk and transportation cost.Secondly, according to the characteristics of the constructed model, this paper designed an improved multi-objective salp swarm algorithm to solve the problem. Finally, taking the planning projects of the medical waste treatment center in Chengdu, Sichuan province as an example, this paper verified the feasibility of the model and the effectiveness of the algorithm through the method of comparative analysis. [ABSTRACT FROM AUTHOR]

Traffic flow prediction is an important and challenging task in building smart city. Accurate forecasting requires consideration of spatio-temporal characteristics consisting of multiple influences such as holiday, similar node, and weather. In order to accurately capture the spatio-temporal characteristics of road network intersections, this paper proposed a prediction model based on graph convolutional neural network, temporal algorithm Prophet and Pearson correlation coefficient to achieve accurate prediction of intersection traffic considering spatial structure, similar nodes, holidays and other influencing factors. Firstly, it introduced pearson correlation coefficient to reduce the influence of similar nodes to improve the temporal algorithm for capturing temporal features. Secondly, it used the graph convolution neural network to capture spatial features; Finally, it determined the fusion weights of the graph convolutional network and the temporal algorithm by linear regression to obtain the results of spatio-temporal fusion prediction. This paper finally extracted the intersection traffic data based on the analysis of Chengdu taxi trajectory data and conducted traffic prediction experiments. The results show that the accuracy of the model proposed in this paper is better than that of most existing baseline methods, compared with the T-GCN, ASTGCN, and AGCRN models, the MAE is reduced by 1.623, 0.724, 0.161, respectively, and the accuracy is improved by 0. 144, 0. 068, and 0. 021, respectively, which verifies the effectiveness of the model in traffic intersection flow prediction. [ABSTRACT FROM AUTHOR]

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering 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 Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering 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 Natural Gas Geoscience is the property of Natural Gas Geoscience 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.)

[Objective] The paper aimed to conduct quantitative calculation and localization research on ecosystem services in Chengdu, to understand the strength, spatial differentiation and impact mechanism of ecosystem services, and to provide policy ideas for the evaluation and supply of ecosystem services in rapidly urbanizing regions. [Method] Based on the gradient space theory, a spatial gradient ring and a spatial gradient transect in Chengdu were established to evaluate the value of ecosystem services, spatial differences and coordination were studied by the evaluation model of ecosystem service value, and coordination degree model in 1990, 2000, 2010 and 2020. [Result] (i) During the study period, the value of ecosystem services in Chengdu decreased by 4.737 billion yuan. (ii) The overall ecosystem service value in Chengdu showed a degrading trend, and the ‘center-periphery’ spatial circle structure radiating from the center to the periphery was obvious, mainly expanding in the southeast (ES) direction, and the northwest (WN) direction was the most stable. (iii) Chengdu has an obvious trend of expanding from the center to the two wings in the north-south direction (S) In the east-west direction (H）, the ecosystem service value gradually declined in the central urban area, rapidly declined in some areas adjacent to the city, and the ecological function areas in the outer suburbs were relatively stable. (iv) From 1990 to 2020, the comprehensive coordination degree (P) on the gradient spatial transect in Chengdu decreased by 2.43. [Conclusion] (i)The value of ecosystem services and comprehensive coordination degree in Chengdu have obvious spatial and temporal differences and significant influence from the expansion of construction land. (ii）The spatial change direction and location of ecosystem services are consistent with the characteristics of urban expansion. (iii) The overall trend of comprehensive coordination (P) is downward. The construction of spatial ecosystem services has an increasingly significant impact on comprehensive coordination (P). [ABSTRACT FROM AUTHOR]

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office 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 Architectural Journal / Jian Zhu Xue Bao is the property of Architectural Journal Editorial Office 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.)

Digital governance requires the government to transform its ability in dealing with data to the ability in governance, which depends heavily on the change of organizational mechanism. The digital governance pattern with the "integration of data and decision-making" is innovated by the local government in our country. A case study is carried out by taking the practice of digital governance by Chengdu government as the research object and taking the analysis framework in technical execution as the research method in this paper. The research shows that, by establishing a new type of pattern with the "integration of data and decision-making" as its feature, the digital governance by Chengdu government has promoted the transformation of technological value and finally achieved the benign change in the governance ecosystem Besides, this paper analyzes the logical in which data should serve for governance, and draws the conclusion that the transformation from its ability in dealing with data to the ability in governance should be promoted by the dual paths: "data serving governance decision" and "data serving government affairs." Finally, it is proposed that the digital governance pattern with the "integration of data and decision-making" is an evolution on the basis of "Internet plus Government Service", which is, on the one hand, helpful in strengthening social trust and confidence, coordinating behaviour and in promoting the innovative motivation for governance; On the other, there still exist potential risks of debris response and conformal governance. [ABSTRACT FROM AUTHOR]

Copyright of Daoism: Religion, History & Society is the property of Chinese University Press 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 Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering 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 Rolling Stock (1002-7602) is the property of Rolling Stock Editorial Office 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.)

Aiming at the online assessment of the health status of metro ZDJ9 switch machines, a health status assessment method of metro switch machines based on real-time monitoring data and variable weight fuzzy comprehensive evaluation is proposed. Firstly, considering the electrical and mechanical characteristics and the external environment of the ZDJ9 switch machine during operation, a hierarchical evaluation index system for health status is established. Secondly, the constant weight of the switch machine evaluation index is determined based on the AHP and the weight is modified according to the relative deterioration degree of the index monitoring data based on the variable weight theory. Finally, the health status is divided into 4 levels, and the membership degree of the index monitoring data to each health level is calculated by the established membership function, and then a hierarchical evaluation model of the switch machine health status based on fuzzy comprehensive evaluation is constructed. Taking the monitoring data of the switch machine of a certain line of Chengdu Metro as an example, the method is verified and compared with the constant weight evaluation method. The results show that, for the serious deterioration of the indicators, the evaluation results of the constant weight method show that the switch machine is still in a "healthy" state, while the evaluation results of the method in this paper are more sensitive to the changes of the index data, and the evaluation result of the health state is "severe", which accords with the actual health condition and can provide the theoretical basis for condition-based maintenance. [ABSTRACT FROM AUTHOR]

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Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office 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 Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. 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 Natural Resources / Ziran Ziyuan Xuebao is the property of Journal of Natural Resources 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 Geography & Geographic Information Science is the property of Geography & Geo-Information Science Editorial Office 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 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 Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering 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 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 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.)

[ Objective) This paper aimed to the quantification of the detailed ranges and dynamics of the environmental factors of the light, temperature, air and moisture in morel cultivation. ( Methods ] Environmental factors in greenhouses for Morchella importuna cultivation were collected in Chengdu plain area using Internet of Things (IoT) technologies. Illumination intensity, air temperature, air relative humidity, oxygen percentage in the air, carbon dioxide concentration in the air, soil temperature and soil water content were recorded every ten mi nutes, in greenhouses with different layers of sunshade-net. Fluctuation models in 24-hour cycle were established for the environmental fac tors at different stages. [ Results] The sunlight in the greenhouses showed a dynamic that indirectly regulated the fluctuating features of the ox Oxygen percentage, relative humidity and temperature in the air, while the average illumination intensity in the greenhouse with the highest mo rel yield were about 2500 - 3500 ks at the noon of sunny days. Sunshade-net effectively prevented over-heating during daytime and over-chill ing during night., diminishing the occurrence of extreme values of air temperature and soil temperature, whereas the cumulative temperatures of the air and the soil, as well as the cumulative values of the relative humidity. oxygen percentage and carbon dioxide concentration in the air, and the soil water content, showed no significant difference between the regimes of different sunshade net layers. The effects of the sunshade-net layers were attenus ting the fluctuations of the environmental factors, The air tem perature was either higher than or similar to the soil temperature during the fruiting stage. (Conclusion) Field conditions ideal for morel cultivation were summarized from the analytical results of the environmental factors, for the reference of field management of morel cul tivation in plain area of southwestern China, which further provided some inspirations for the engineers hoping to develop factory-mode tech nologies of morel production. [ABSTRACT FROM AUTHOR]

[Objective] This paper aimed to investigate the variation characteristics of soil nutrients of cultivated land at different elevation in the transition zone between plain and mountain of Chengdu. [Method] Pengzhou city as the study area was chosen, 1142 topsoil samples at different elevation were collected, and the nutrient data were analyzed with traditional statistics, correlation analysis, variance analysis, semi-variogram model optimization and Co-kriging interpolation. [Result] The correlation relationship between available potassium(AK), soil organic matter(SOM) and elevation were overwhelmingly positive, and the correlation relationship between alkali-hyclrolyzable nitrogen(AN), available phosphorus(AP) and elevation were overwhelmingly negative. The content of AN and AP decreased with elevation increasing and then obviously rebounded at the area above 913 m, the content of AK and SOM increased with elevation. The area with relatively low content of AN, AP and SOM was mainly concentrated in the zone of the most transitional elevation. [Conclusion] The result of this study could be helpful for the improvement of the productivity of cultivated land, soil utilization and protection in the transition zone between plain and mountain of Chengdu, which was of great significance for promoting the sustainable utilization of the resource of cultivated land and ensuring southwest China’s grain security. [ABSTRACT FROM AUTHOR]

[Objective] Eucalyptus globulus, E.grandis and E.robusta are green plants widely cultivated in Chengdu, and this paper aimed to exploit the utilization potential of Eucalyptus resources. [Method] The essential oils from three Eucalyptus species leaves were extracted by using the modified steam-distillation extraction method, and the chemical components were determined by gas chromatography-mass spectrometry（GC-MS）. The effects of the essential oils on proliferation of human hepatoma cells（SMMC-7721） in vitro was studied by 3-（4, 5-dimethyl-2-thiazolyl）-2, 5-diphenyl-2-H-tetrazolium bromide（MTT） assay. [Result] The oil yields of globulus, E.grandis and E.robusta were 3.67 %, 1.21 % and 0.43 %, respectively. The essential oil of E.globulus, E.grandis and E.robusta contains 34, 34 and 31 components. A total of 17 components, such as α-pinene, camphene, limonene, eucalyptol, fenchol, campholenal, borneol, carvone, alloaromadendrene, caryophyllene and o-cymene, were common components of three essential oils. The two main components were α-pinene and eucalyptol in the essential oil of E.globulus, E.grandis and E.robusta, the relative contents of α-pinene were 17.18 %, 17.89%and 41.91%, respectively;The relative contents of eucalyptol were 59.55 %, 50.49 % and 7.68 %, respectively. Three Eucalyptus essential oil significantly inhibited proliferation of human hepatoma SMMC-7721 cells and human normal liver L02 cells.SMMC-7721 cells were more inhibited than L02 by the essential oil of E.robusta, E.grandis and E.Globulus, with half maximal inhibitory concentration(IC50) values of 4.66, 7.36 and 13.53 μg·mL-1 after 24 hours treatments, respectively. The essential oil from E.robusta had a best inhibiting effect on SMMC-7721 cells. [Conclusion] These results indicated that the chemical components and contents of essential oils from different species of Eucalyptus in the same area were different, and the essential oils of Eucalyptus had the potential to be used as antitumor drugs. [ABSTRACT FROM AUTHOR]

To ensure the safety of the urban transit network so as to improve the operation efficiency of the entire traffic network, this paper took the transit network of Chengdu city for instance, it analyzed the invulnerability under random and deliberate attacks based on revealing the network topology. The simulation results show that the node number removed from the network affects the invulnerability little in both random attacks and deliberate attacks on the basis of node degree. At the same time, it finds that the less node number removed from the network, the worse invulnerability the network shows in deliberate attacks based on not only node betweeness but node efficiency. Furthermore, the impacts of deliberate attacks based on node betweeness on the network invulnerability are more remarkable than those based on node degree and efficiency. [ABSTRACT FROM AUTHOR]

To study the impact on house value of distance to stations of west extension line of metro line 2 in Chengdu within 800 meters radius area, this paper surveyed residential real estate data along the urban rail transit stations within 800 meters radius area, selected appropriate characteristics variables, and constructed semi-logarithmic equations and logarithmic equations based on hedonic price model, and then built overall equation and distance interval equation by a single distance variable and distance interval variables, and verified the impact on house value of distance to stations of west extension line of metro line 2 in Chengdu. Result shows that, within 800 meters to the metro stations, house values experience an overall downward trend with the increase of distance to the metro stations, the significance of the impact is high. But based on the different distance intervals, house values have seen a trend of "low in the two ends, high in the middle, declining in the overall". And the degree of impact on house value of distance variables, compare to other major variables (distance to the CBD, developer brand, etc.), is relatively low. [ABSTRACT FROM AUTHOR]

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction Editorial Office 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 China Sciencepaper is the property of China Sciencepaper 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.)