Beijing Daxue Xuebao (Ziran Kexue Ban)/Acta Scientiarum Naturalium Universitatis Pekinensis

In order to explore the historical annual heavily PM2.5 polluted days and their health loss, the study constructs a daily air quality dataset for 31 provinces of China from 2001 to 2013. Further, it evaluates the health impacts especially the premature death and the economic loss due to the heavy PM2.5 pollution days of each year since 2001 for each province, by applying the latest results of dose-response in epidemiologic studies and taking account of the age structure of population as well as valuation approaches. The result shows that since 2001, heavily polluted situation(above the defined threshold, here the 2nd grade of air quality standard is applied for practical reason) for PM2.5 occurred in 71 percent of the provinces on a yearly basis. Although the average concentration of heavily polluted days did not have much variations during the thirteen years and the trend went down during 2001–2012 in terms of occurrence, heavily polluted situation increased dramatically in frequency in 2013. As a result, the proportion of heavily polluted days in 2013 was the highest during 2001–2013. It is estimated that over 65000 premature deaths was caused by heavy PM2.5 pollution days in 2013, which can be assessed as the 28.1 billion Yuan loss in economic term, 54 percent of the total economic loss in these thirteen years equivalently. The surge of economic loss in 2013 was attributed to the lasting heavy PM2.5 pollution in January 2013 and eight provinces in eastern and middle China.

Mu Qua

Beijing Daxue xuebao. Ziran kexue ban

Assessment of the Trend of Heavy PM_(2.5) Pollution Days and Economic Loss of Health Effects during 2001–2013

2001-2013年重PM_(2.5)污染日趋势及健康效应经济损失评估

Wang Fenjua

Case Study of Wuhan Dust Pollution in May 2014

2014年5月武汉尘污染案例研究

The authors propose a simple but effective distance based method to identify forms with similar layouts by measuring the user filled-in data, preprinted data and dithering data. The proposed method utilizes three kinds of weight components to mitigate the impact of randomness of user filled-in data, consistency of similar layouts and position dithering respectively. Experimental results show that the proposed method can achieve more than 90% classification accuracy on a series of data sets, which is significantly better than the results of the state-of-the-art method.

Wang Simen

A Study on Classification of Forms with Similar Layout

相似布局形式分类研究

The methods of land ecological sensitivity analysis were discussed, based on the concept of protection goes first to the construction land pattern. With a combination of comprehensive index method, fuzzy evaluation method and RS/GIS approach, an integrated method of construction land suitability assessment was proposed. It offers three factors that mainly influence the construction land-use environment including land ecological sensitivity, natural condition and social economy environment, and it introduces the fuzzy membership functions to improve the model algorithm. The evaluation results would hierarchically display different land ecological sensitivity endowment and land-use environment, which leads to analyze the construction land spatial distribution in a land ecological security pattern. Taking Xiangjiang New District of Changsha City as a case, 14 indexes were chosen in accordance with the local conditions, to assess construction land suitability of this area. The results objectively show the region's land ecological environment and land-use condition, and give an ecological security spatial arrangement of the construction land pattern, which can provide guidance to land-use planning of the resource-economical and environment-friendly society.

Zhang Shiy

Research on Construction Land Evaluation Based on Land Ecological Sensitivity Analysis

基于土地生态敏感性分析的建设用地评价研究

The Comprehensive Air Quality Model with extensions(CAMx), a 3-D regional chemical transport model, was used to simulate ozone concentrations in the Pearl River Delta(PRD) in November, 2009. Ozone Source Apportionment Technology(OSAT) was applied to investigate sources of two typical ozone episodes and a clean day as comparison. The results showed that emissions from urban Guangzhou and Dongguan mainly contributed to local areas and the southwestern part of PRD(15–30 μL/m3), while emissions from Shenzhen Baoan district(15–25 μL/m3) mainly affected the Pearl River Estuary. Mobile sources and solvent usage sources were two major contributors to ozone formation and had an influence in most areas of the central and western PRD. Mobile sources could contribute as much as 50 μL/m3 hourly ozone concentration to the boarding area of Foshan and Guangzhou. Trans-boundary import of ozone made episodes more likely to occur in PRD under unfavorable weather conditions, however, the ozone precursors emitted within the PRD region were the main cause of high ozone concentrations during ozone episodes. As a result, the strategies on controlling emissions within the PRD region are the key to the reduction of ozone pollutions in PRD.

Chen Ha

Ozone Source Apportionment of Typical Photochemical Pollution Episodes in the Pearl River Delta in Autumn

珠江三角洲秋季典型光化学污染事件的臭氧来源解析

Existing sentiment analysis focus on the emotional tendency, which are lack of detailed description of all kinds of emotions, they can't intuitively reflect the emotional change of social groups. An emotional analysis method based on the combination of dependency parsing and artificial tagging was proposed. Facial expression animation to present emotions analysis was realized. The microblog crowd's emotion in different areas for different social events was visualized. The experimental results show that the model could closely and effectively simulate the crowd emotion, and it could provide a new way of the analysis of network public opinion based on large data.

Liu Cuijua

Research on the Visualization Method of Social Crowd Emotion Based on Microblog Text Data Analysis

基于微博文本数据分析的社会群体情绪可视化方法研究

Based on the efficiency and effectiveness issue of traditional simiar spatial textual objects retrieval, a semantic aware strategy which can effectively and efficiently retrieve the top-k similar spatial textal objects is proposed. The efficient retrieval strategy which is based on spatial textual objects is built on a common framework of spatial object retrieval, and it can satisfy the efficiency and effectiveness issues of users. Extensive experimental evaluation demonstrates that the performance of the proposed method outperforms the state-of-the-art approach.

GU Yanhu

Similar Spatial Textual Objects Retrieval Strategy

相似空间文本对象检索策略

This paper presents an innovative method to align two glyph contours with three steps. First, 2D Bezier curve control points of glyph contours of each character are expanded into 3D space. Second, a Gaussian Mixture Model(GMM) is constructed using this 3D point set. Finally, the authors establish alignment by minimizing the Euclidean Distance(L2) between two GMMs and then apply transformation accordingly. Expansion to 3D space helps make use of inherent constraints of Chinese calligraphy beyond 2D coordinates. The advantage of using Gaussian Mixture Model is to maintain both the overall shape property and the local writing features during the alignment process. Experiments results verify the feasibility and effectiveness of proposed method and it performs well for both single stroke and whole character.

Liu Yingbi

Chinese Calligraphy Alignment Based on 3D Point Set Registration

基于三维点集配准的中国书法对齐

This paper proposes a method to construct Bilingual Movie Knowledge Graph(BMKG). The authors first builds Bilingual Movie Ontology(BMO) through a semi-automatic way, and aligns each data source with it in order to ensure semantic consistency of heterogeneous data sources. For entity linking, the proposed method makes best use of the field characteristics and calculate entity similarity based on both Word2 Vec and TFIDF models, which greatly improve entity linking. For entity matching, a similarity flooding based algorithm is proposed, which utilizes the intrinsic links between the movie data sources, addressing the problem of similarity computation between cross-lingual entities. The experiment results show that the entity matching precision is over 90% when the threshold is above 0.75. In addition, a movie knowledge graph sharing platform is also built to provide open data access and query interface.

Wang Weiwe

Research on the Construction of Bilingual Movie Knowledge Graph

双语电影知识图谱构建研究

Entity linking is the process of linking name mentions in text with their referent entities in a knowledge base. This paper tackles this task by proposing an approach based on topic-sensitive random walk with restart. Firstly, the context information of mentions is used to expand mentions and search the candidate entities in Wikipedia knowledge base for mentions. Secondly, graph can be constructed in accordance with the intermediate result in the pre step. Finally, the topic-sensitive random walk with restart model is used to rank the candidate entities and choose the top 1 as the linked entity. Experimental results show that proposed approach on KBP2014 data set gets F score 0.623 which is higher than every other systems' mentioned in this paper. The proposed approach can improve the entity linking system's performance.

ISSN	0479-8023
h-index	32

出版信息	出版商: Peking University，出版周期: ，期刊类型: journal，开源期刊: 否
基本数据	创刊年份: 2001，原创研究文献占比: 0.00%，自引率:N.A.， Gold OA占比: 0.00%

Beijing Daxue Xuebao (Ziran Kexue Ban)/Acta Scientiarum Naturalium Universitatis Pekinensis

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