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To provide diverse book lending channels and services to the public and to guide healthy competition in library industry, this paper discusses the coopetition relationship between online shared bookstores and libraries from the perspective of readers' choice behavior. According to the questionnaire survey from 187 readers in Guangzhou, MNL model is adopted to quantitatively analyze the effect of various factors such as personal attributes, borrowing requirements and habits on readers' choice. Research shows that online shared bookstore and library, mainly public library, have different competition in terms of multi-dimensional needs and preferences. Thus, this paper proposes the potential cooperation mode between online bookstore and library in collection, data and space, so as to promote the mutually beneficial coexistence between them. [ABSTRACT FROM AUTHOR]

The background of "emotional turn" calls for the study of affective geography to move away from the paradigm of subjective experience to a broader study of social space. As a complex social and cultural integration, the learning space for the elderly is no longer only a pure facility for the aged. The daily life, stage performance and social interaction of the elderly in the space are endowed with more special emotional significance. Taking Guangdong Old Cadres University as the main case study, this paper deconstructs the spatial perception of elderly students into three emotional stages, namely Cognition, Identity and Spillover, from the perspective of emotional geography, through long-term observation, participation and integration into the learning and social life of the elderly in and out of class. This paper holds that the learning place is not only a substantial spatial scale, but also a space with special social connection and sense of belonging around "community" and "emotion". Back to the old place by learning a positive space projection self definition, "to participate in learning" dynamic atmosphere triggers the elderly, the young positive emotions, space of social network also intimacy, a sense of belonging for the old emotional support, a positive local identity and sense of community ACTS on the spatial construction become stable, ageing resistant negative positive spillover benefits. This paper provides real case support for deconstructing learning space from the perspective of emotional geography, focuses on active actors in urban daily life, and provides empirical suggestions for the development of geriaterriendly communities. [ABSTRACT FROM AUTHOR]

In the 18th and 19th centuries, the exported paintings recording realistic themes with realistic skills was popular in Guangzhou. Pith painting was the watercolor painting drawn on rice paper, which was thin and colorful, in which characters and scenes were vivid, recording production and life at that time in details. Therefore, it is the precious image data to study the society, production, life and folk customs of that time. Based on the analysis and research of a set of pith paintings with the theme of Pekoe in China (Hainan) Museum of the South China Sea, the cultivation, production, trade and circulation of Pekoe in the Qing Dynasty are discussed in details. [ABSTRACT FROM AUTHOR]

Woody plants are crucial biotic components of greenway in urban areas. Taking Guangzhou greenway as the research object, the present paper carried out a synthetic analysis on tree species composition, flowering periods of ornamental species, important value, and the usage of native plants in the whole municipality and each district in Guangzhou city, based on field investigations and statistical processing. The results were the follows: (1) More than 28 common species were used as ornamental purpose in Guangzhou. Flowering species existed almost throughout the whole year, but concentrated on the summer season; specifically, there were 15, 14 and 12 flowering species found in June, July and August, respectively. (2) The dominant plant species in Guangzhou greenway were Ficus microcarpa, Bauhinia purpurea, F. altissima, and Mangifera indica based on analyzing the relative important values for all species. The proportional rate of native plants was around 73% of the total, but several species (e.g., F. microcarpa) was planted too many to form a simple community composition. (3) Woody plants grew well along all greenway with few reports on disease or insect pests, but regular monitoring and controlling measures were indispensable. (4) DBH of nine major tree species showed a linear positive correlation with crown width and height. Therefore, both city managers and forest researchers should enrich plant taxa in subsequent afforestation activities and keep standardized management measures to avoid homogeneous community composition, to improve overall forest landscape, and to maintain high-quality ecological services in urban regions. [ABSTRACT FROM AUTHOR]

The study on the equity of urban green space layout based on the quantification of ecosystem services is oriented to the improvement of human well-being, which is helpful to promote the equity of ecological environment and the sustainable development of cities. Based on the analysis of the urban green space distribution and ecosystem service value of green space of the blocks in Yuexiu District,Guangzhou in 2020, this study used the location entropy method to analyze the fairness of green space ecosystem services available per capita in each block. The results showed that: (1) The population and urban green space in Yuexiu District were significantly spatially heterogeneous. (2) The comprehensive ecosystem service value of green space varied greatly among the blocks in Yuexiu District, with a high spatial distribution in the north and a low spatial distribution in the south. (3) There were some unfair spatial distribution of green space in the district. The two blocks, Dengfeng and Hongqiao, had extremely high location entropy. The seven blocks of Renmin, Guangta, Zhuguang, Dadong, Datang, Meihua Village and Kuangquan had low or extremely low location entropy. It was proposed to optimize the green space layout of the study area by strictly protecting important ecological green space, inserting green space in subtleties, increasing urban public green space by using urban wasteland, adding riverside greenways with sports and leisure functions, increasing urban green space under the background of old city reconstruction, and increasing the urban vertical green area. The paper results can provide some reference for the study of the fairness of green space layout in the same type of high population density cities, which can help to improve the level of residents' health and well-being. [ABSTRACT FROM AUTHOR]

Relying on the Hongshengsha-Yufengwei Section Tunnel Project of the second phase of Guangzhou Metro Line 7, this paper used the particle swarm optimization random forest method (PSO-RF) to establish a sealed cabin pressure prediction model in the dual-mode shield soil pressure boring mode. Through the correlation analysis of shield boring parameters, the tunneling parameters that had a great influence on the pressure of the sealing chamber were screened out, including screw speed, screw torque, cutterhead speed, propulsion speed, penetration degree, cutterhead torque, and total thrust, and the screened tunneling parameters were used as the input parameters of the prediction model, and the pressure of the sealing chamber was used as the output parameter of the model to predict the pressure of the sealing chamber. The results showed that the random forest PSO-RF prediction model improved by particle swarm algorithm could effectively predict the pressure of the dual-mode shield sealed cabin, and compared with the traditional neural network prediction model, the PSO-RF model had higher prediction accuracy, the average absolute error was within 10%, and the predicted value and the actual goodness-of-fit R2 were 0.901 4, which was significantly superior to the BP neural network in terms of prediction accuracy and generalization ability of the model. [ABSTRACT FROM AUTHOR]

This paper proposed constrained deep reinforcement learning( CDRL) to compute the fastest route online using taxi drivers' experience in different time period. Firstly, this paper described the extraction of experiential road segment database (ERSD). Then it introduced CDRL method, which mainly comprised of two phase: bounded condition of route and deep Q-learning algorithm. In the first phase, the task was to generate alternative constrained road segments of OD pair. In the second phase, it devised deep Q-learning algorithm to learning the experience of taxi drivers, and computed the fastest route of a given OD according to their departure time. Lastly, this paper tested an empirical studies in CBD of Guangzhou. The results show that the routes computed by CDRL method is approximately equal to shortest route ( SR) and fastest route (FR) method in travel time and route length. Furthermore, the CDRL method notably outperforms FR and SR in computing efficiency, so it is more suitable for online fastest route computation. [ABSTRACT FROM AUTHOR]

Litchi picking robot is an important tool for improving the automation of litchi picking operation. The spatial position information of litchi cluster needs to be acquired when the robot picks litchi normally. In order to guide the robot moving to the picking position and improve the picking efficiency, the vision pre-positioning method of litchi picking robot under large field of view is proposed in this paper studied. Firstly, using the binocular stereo vision system composed of two industrial cameras that have been calibrated, 250 pairs of litchi cluster images under large field of view was taken in the litchi orchard in Guangzhou, the spatial positions of key litchi clusters were recorded by using a laser range finder, and the results were compared with those tested in the paper. In order to expand the sample size, the original image and the polar line correction image were randomly cropped and scaled in a small range, and the final image data set was 4 000 sheets. After that, by using labeling, the data set of the target detection network was created. Secondly, by using the YOLOv3 network and the DenseNet classification network, combined with the characteristics of single target and single scene of litchi cluster detection task (only for orchard environment), the network structure was optimized, a Dense Module with a depth of 34 layers and a litchi cluster detection network YOLOv3-DenseNet34 based on the Dense Module was designed. Thirdly, Because of the the complexity of the background image under large field of view, the dense stereo matching degree of the whole image is low and the effect is poor, at the same time, some litchi clusters can not appear in the public view of the image at the same time, therefore, a method for calculating sub-pixel parallax was designed. By solving the quadratic curve composed of parallax and similarity, the parallax under sub-pixel was used to calculate the spatial positions of the litchi cluster. Through the comparison with the original network of YOLOv3, the test network performance of the paper was tested, and found that the YOLOv3-DenseNet34 network improved the detection accuracy and detection speed of the litchi cluster, the mAP (mean average precision) value was 0.943, the average detection speed was 22.11 frame/s and the model size was 9.3 MB, which was 1/26 of the original network of YOLOv3. Then, the detection results of the method were compared with the results of the laser range finder. The max absolute error of the pre-positioning at the detection distance of 3 m was 36.602 mm, the mean absolute error was 23.007 mm, and the average relative error was 0.836%. Test results showed that the vision pre-positioning method studied in this paper can basically meet the requirements of vision pre-positioning under large field of view in precision and speed. And this method can provide reference for other vision pre-positioning methods under large field of view of fruits and vegetables picking. [ABSTRACT FROM AUTHOR]

The continuous advancement of economic globalization and informatization, along with the rapid construction of transportation infrastructure, have made cities more closely connected and made urban networking a prominent trend. Network news is easily accessible and contains bundant geographical information. Studying urban networks from the view of toponym cooccurrences in the news is a brand -new perspective, and conclusions may help clarify the status of cities, deepen the understanding of the structure of urban networks. This paper conducts research from contact, node and network successively. Firstly it proposes a new method aiming at measuring relatedness of city pair based on toponym co-occurrences; then it uses the centrality of social network analysis to characterize urban influence and explores its spatial distribution; finally it studies the characteristics and structure of urban networks. Results show that the proposed measurement approach highlights the strength of the relatedness, and makes up for the shortcomings of Ochiia coefficient method such as ignoring multiple diverse toponyms in the news; coastal cities possess higher urban influence than inland ones; the backbone urban network presents an approximately diamond - shaped spatial structure, metropolises such as Beijing, Shanghai, Guangzhou, and Chongqing are the core nodes. [ABSTRACT FROM AUTHOR]

In this paper, energy performance of a loop-heat-pipe (LHP) type solar photovoltaic/thermal (PV/T) heat pump water heating system is studied to evaluate its feasibility in three different climatic regions. A mathematic model of this system in our former study is built and validated using outdoor test data. On the basis of this model, influences of main structural design parameters including the installation angle and the orientation of the PV/T collector/evaporator are discussed and main parameters are optimized to further improve system operation performance. Based on optimal design parameters, economic feasibility of the proposed system under different weather conditions is analyzed using the life cycle cost (LCC) method. The system is integrated with solar PV/T, loop heat pipe and solar assisted air source heat pump technologies. This combined approach is benefit for improving solar energy comprehensive application efficiency of conventional solar PV/T systems. Moreover, it enlarges the application region of traditional air source heat pump water heating systems. Depending on different solar radiation conditions, this system can operate in different modes including solar photovoltaic LHP mode, solar assisted air source heat pump mode and the only air source heat pump mode. In this study, Beijing, Shanghai and Guangzhou were selected as typical representative cities in cold area, hot summer and cold winter area, hot summer and warm winter area. Typical meteorological year (TMY) data of three cities were extracted from TRNSYS. Based on TMY data, annual operation performance of the proposed system is calculated through the validated dynamic mathematic model. Firstly, PV/T collector/evaporators of three systems are all fixed in the south direction and the same installation angle (35°) was chosen. In this case, annual net power consumptions and solar heating fractions of three systems are calculated and compared. Then installation angles and orientations are optimized to ensure maximum solar energy application. The investigation results show that, among three cities, the solar heating fraction in Guangzhou is the largest. And the least electricity is consumed in Guangzhou, which is decreased by 43.9% and 44.7% respectively compared with those in Beijing and Shanghai. The comprehensive photothermal efficiency in Guangzhou is 8.19%, 5.58% higher than those in Beijing and Shanghai. Therefore, from the view of solar energy comprehensive efficient utilization, the application of the system is most proposed in Guangzhou, and then followed by Shanghai and Beijing. Considering impacts of installation angles and orientations, the ideal installation inclination of the system in Beijing, Shanghai and Guangzhou are 35°, 25°, and 35°, and the optimal installation directions of Beijing and Shanghai are facing the south, while that of Guangzhou is 30°east to the south. With the optimal parameters, it is found that solar heating fractions in Beijing and Guangzhou (i.e. 57.42% and 58.45%) are slightly higher than that in Shanghai. It is concluded that influences of two structural parameters are different for such system in different climatic areas. To ensure maximal solar energy application, it was necessary to optimize these two parameters. For the life cycle cost analysis, a traditional air source heat pump hot water heating system is chosen as the base system. The analysis results indicate that the initial investment of the system increases significantly, which is 2.5 times of that of the base system. However, the annual power consumption of the system is about half of that of the traditional system. Besides, solar power supply fractions in Beijing, Shanghai and Guangzhou are 53%, 51% and 66% respectively. As a result, the total operation and maintenance fees in the life cycle drop significantly, which are reduced by 67.86%, 59.00%, and 62.21% in Beijing, Shanghai and Guangzhou. The life cycle cost is correspondingly reduced by 58.75%, 49.83% and 53.09% in three cities. In conclusion, the application of this system is feasible for considered weather conditions in terms of both the operating performance and economic benefits. [ABSTRACT FROM AUTHOR]

In this paper, we propose an individual income level inference method based on travel behavior of urban residents. Firstly, we define 13 residents' travel behavior features from 3 different aspects. These features are the mobility indicators based on trajectories, home-based travel characteristics, and activity chain patterns. Secondly, 80% of the daily travel diary data of residents in Guangzhou in 2013 is taken as the training sample and the remaining as the test data. Thirdly, the random forest method is trained and used to infer individual's income level. The experiment results show that our proposed method can obtain an overall accuracy of 80%. Among 13 travel behavior features, the home-based features (i.e. the mode of the travel distance from home during working time (9:00 AM to 18:00 PM)), the activity chain pattern, and travel distance and scope related features (i.e., the maximum distance between two successive activity points, and radius of gyration) have high feature importance. However, the features representing the spatial heterogeneity of the activity points have relatively low importance, such as the spatial diversity. [ABSTRACT FROM AUTHOR]

The construction of high- speed rail in China improves the comprehensive transportation systems significantly, while challenging the development of domestic air transportation at the same time. Based on the timetable data from 2007 to 2014, the overlapping market of HSR and air network is identified from the perspective of direct connection between city pairs. In 2007, the overlappping network only had 21 city pairs with direct flights and highspeed trains, and the number dramatically increased to 277 in 2014. This paper first analyzes the potential influence of HSR development on airlines and its spatial distribution. Then, a random effect regression model is established to measure the ex- post effects of the entry of HSR on air passenger flows of all the 277 city- pairs, among which, 94 city- pairs connected with the three hub cities, and 183 city-pairs connected with other feeder airports in China. The results are as follows: (1) Despite the fact that HSR and air transportation systems in China are developing in parallel, the entry of HSR has caused a modal shift from air transportation. The reduction on air travel demand caused by G trains is more obvious than that of D trains. (2) The air travel demand between inter-cities within the same or nearby provinces decreases sharply. (3) Distance, GDP, and rank of airports are significant positive factors in increasing air travel demand. (4) Due to various flight networks, preference for air transport, and sensitivity to travel time in hub cities, city pairs connected with Beijing, Shanghai or Guangzhou are more competitive for air transportation than for HSR. [ABSTRACT FROM AUTHOR]

In 1814, Li Huaiyuan, alias Li Yao, Ayao (Ayew), a linguist (tongshi) in Guangzhou, was arrested and thrown into jail by the Chinese authorities, apparently for his service to the British traders in bringing letters and presents to a senior minister in Beijing. The British made various attempts to rescue him, including suspending trade with the Chinese. Ayew was ultimately sent to exile to Xinjiang. The present paper examines this so-called "Ayew Incident" in the history of East India Company trade in China. It analyses the real causes for the arrest of Ayew and explains how and why the British would want to rescue him at the risk of great loss in revenue. It hopes to demonstrate the significant role and position played by the linguists in the Canton System and Sino-British relationship in the eighteenth and nineteenth centuries. [ABSTRACT FROM AUTHOR]