An Exciting Time for Steel City

Panzhihua, in south Sichuan’s basin, is aptly called West China’s Industrial Pearl, and "treasure bowl." This city is well known as the home of Panzhihua Iron and Steel Group Company and Ertan Hydropower Station. At the beginning of 2004, two major events thrust this city into the limelight.

PRINT CHINA 2007——No.1 printing exhibition in China in 2007 meets you at Dongguan city in spring time

The first International Printing Technology Exhibition of China（Guangdong）is held from 10th-14thApril 2007.The abbreviation of the name of this exhibition is PRINT CHINA. The first PRINT CHINA attracts not only large quantity of printing and packaging equipment and material suppliers home and abroad to participate in the show,but also enormous num- bers of domestic and overseas visitors to attend the show.

Spatial-temporal Characteristics and Factors Influencing Commuting Activities of Middle-class Residents in Guangzhou City, China

The middle class in metropolitan Chinese cities has become an important social group. With the rapid development of urbanization and constant advancement of suburbanization, the middle class has increasingly come to influence city traffic. Research into middle-class commuting activities thus has practical significance for improving traffic congestion and reducing the commuting burden in metropolitan cities. Based on a dataset formed by 816 completed surveys, this paper analyzes the commuting mode, time and distance of middle-class residents in Guangzhou City using the descriptive statistical method. The results indicate that private cars are the main commuting mode, followed by public transport. Meanwhile, middle-class residents mainly undertake medium-short time and medium-short distance commuting. The study subsequently uses multilevel logistic regression and multiple linear regression models to analyze the factors that influence commuting mode choice, time and distance. The gender, age, number of family cars, housing source and jobs-housing balance are the most important factors influencing commuting mode choice; housing, population density, jobs-housing balance and commuting mode significantly affect commuting time; and transport accessibility, jobs-housing balance and commuting mode are the notable factors affecting commuting distance. Finally, this paper analyzes what is affecting the commuting activities of middle-class residents and determines the differences in commuting activity characteristics and influence factors between middle-class and ordinary residents. Policy suggestions to improve urban planning and urban management are also proposed.

A framework based on sparse representation model for time series prediction in smart city

Smart city driven by Big Data and Internet of Things(loT)has become a most promising trend of the future.As one important function of smart city,event alert based on time series prediction is faced with the challenge of how to extract and represent discriminative features of sensing knowledge from the massive sequential data generated by IoT devices.In this paper,a framework based on sparse representa-tion model(SRM)for time series prediction is proposed as an efficient approach to tackle this challenge.After dividing the over-complete dictionary into upper and lower parts,the main idea of SRM is to obtain the sparse representation of time series based on the upper part firstly,and then realize the prediction of future values based on the lower part.The choice of different dictionaries has a significant impact on the performance of SRM.This paper focuses on the study of dictionary construction strategy and summarizes eight variants of SRM.Experimental results demonstrate that SRM can deal with different types of time series prediction flexibly and effectively.

Control system design of hybrid fuel cell city bus

This paper introduced the design of the hybrid powertrain of the Fuel Cell City Bus demonstrated in 2008 Beijing Olympic Games. The configuration of the hybrid fuel cell powertrain was introduced. The safety of hydrogen storage and delivery system, the hydrogen leakage alarm system were developed. The real-time distributed control and diagnosis system based on the Time Trigger Controller Area Network （TTCAN） with 10 ms basic control period was developed. The concept and implementation of processor （or controller） monitor and process （or task） monitor technique based on the TYCAN were applied in this paper. The fault tolerant control algorithm of the fuel cell engine and the battery man- agement system were considered. The demonstration experience verified that the fault tolerant control was very important for the fuel cell city bus.

Accessibility Comparison and Spatial Differentiation of Xi’an Scenic Spots with Different Modes Based on Baidu Real-time Travel

A study of the accessibility of a city’s scenic spots via different travel modes can contribute to optimization of tourism-related transportation while improving tourists’ travel-related satisfaction levels and advancing tourism. We systematically analyzed the accessibility of 56 scenic spots in Xi’an City, China, via car and public transport travel modes using the real-time travel function of the Baidu Maps API(Application Programming Interface) along with spatial analysis methods and the modal accessibility gap index of scenic spots. We obtained the following results. First, maximum and minimum travel times using public transport exceeded those using cars. Moreover, the accessibility of scenic spots via cars and public transport presented a circular spatial pattern of increasing travel time from the center to the periphery. Contrasting with travel by public transport, car travel showed a clear time-space compression effect. Second, accessibility of the scenic spots via cars and public transport showed some spatial heterogeneity, with no clear advantages of car accessibility in the central urban area. However, advantages of car accessibility were increasingly evident moving from the center to the periphery. Third, whereas the correlation of the modal accessibility gap index of scenic spots in Xi’an with global space was significantly positive, local spatial interdependence was only evident in some inner city areas and in marginal areas. Moreover, spatial heterogeneity was evident in two regions but was insignificant in other areas, indicating that the spatial interdependence of the modal accessibility gap index in most scenic spots was not apparent in terms of the overall effect of public transport routes, road networks, and the distribution of scenic spots. The improvement of public transport coverage in marginal areas and the optimization of public transport routes in central urban areas are essential tasks for improving travel using public transport in the future.

Changing the World,One City at a Time

In this series,Beijing Review will profile several "sister city" relationships between the United States and China.Washington,D.C.-based Sister Cities International facilitates the city pairings,as part of a 50-year-old mission to promote"citizen diplomacy."Our first sister city profile is on Pasadena,California and its counterpart Xicheng District in Beijing.

Enlightenment From the Development of Ancient City Planning in China in the Ancient Times

China is among the first countries in the world in developing the science of urban planning,and has evolved her own unique system.Through investigating the structural features of the plan-ning system,the laws governing its development and the causes of the rise and fall of the ancientplanning system,this article attempts to propose some insights useful to the establishment and de-velopment of the modern city planning in China.

基于CityGML的三维城市模型实时可视化研究

针对CityGML(City Geography Markup Language)城市模型实时可视化问题,提出一种流式读取与数据绑定结合的快速解析办法以及多线程并行处理的数据加载策略,通过将模型数据重新组织成Direct3D网格对象实现了对三维图形的高效渲染。实验部分给出了.Net平台下基于C#与Direct3D的三维可视化结果,证明了方法的有效性。

Study on Design Rainstorm Profile in Liuzhou City Based on Pilgrim &Cordery Method

Liuzhou City is located in Guangxi Zhuang Autonomous Region of China. It has a warm and rainy climate and belongs to the middle subtropical monsoon climate. It is a rainstorm and flood-prone area. The work of flood drainage and waterlogging prevention is very important. The “minute to minute” rainfall process data of Liuzhou National Meteorological Observation Station from 1975 to 2014 and the Pilgrim & Cordery method were used to estimate the short-time design rainstorm profile of Liuzhou City, and the profiles of the rainfall lasting for 30, 60, 90, 120, 150, and 180 min were obtained. The research shows that the same rain duration and different recurrence period conditions are consistent with the rainstorm profile. The rainfall duration of 30, 60, 90, 120, and 180 min generally shows single-peak rainstorm profile, and the rainfall duration of 150 min shows double-peak rainstorm profile. Most peaks of each short-time design rainstorm profile are at or ahead of the 1/3 part of the entire rainfall process. During the same recurrence period, the rainfall in peak period fluctuated with the increase of the duration, and the intensity of rainfall increased with the prolonging of the recurrence period.

Influence of seismicity parameter uncertainty on seismic hazard estimation of cities and towns

The influence on seismic hazard estimation for 310 cities and towns in the whole nation are studied in particular,owing to uncertainty of seismicity parameters caused by non-uniqueness in selecting statistical time ranges. Andthe regional sketch maps of the average varying values of intensity and the average relative varying values of peakacceleration with different probability of exceedance in 50 years are drawn in the Chinese mainland.

Research on Renewal and Renovation of Old Urban Districts under the Concept of Resilience: A Case Study of Old Urban Districts of Wu'an City

City resilience is a hot topic in the field of urban planning,and it is a solution and urban renewal and renovation approach for the problems of modern cities.Taking the old urban districts of Wu’an City,Hebei Province for example,this paper applied analysis methods such as space syntax and facility diversity to analyze the current problems of the study areas from the perspectives of road traffic,supporting facilities,proposed urban design renewal and renovation strategies for old urban districts,which would be significant for defining the timing sequence of urban renewal,improving the locals’ life quality and promoting resilience of old urban districts.

京津冀城市群综合承灾能力时空异质性研究

基于2010—2020年京津冀城市群13个城市的调查数据,应用Kernel密度估计方法、空间自相关模型及Dagum基尼系数,分析不同时期京津冀城市群综合承灾能力时空动态演进分布格局及地区差异。结果表明:(1)在时间维度,2010—2020年京津冀城市群综合承灾能力总体呈现逐渐上升趋势,但京津冀城市群各市之间的承灾能力水平差距逐渐增大,区域整体呈现非均衡特征;(2)在空间维度,2010—2020年京津冀城市群综合承灾能力在空间分布上关联度较低,不存在显著的集聚或分散特征,但有局部地区产生聚集特点,属于“高-高”“低-低”空间聚集型城市较多,在此期间京津冀城市群综合承灾能力呈现空间集聚与空间分异并存;(3)京津冀城市群综合承灾能力的总体差异呈现上升趋势,北京-河北地区间差异最大,地区间差异是总体差异的主要来源。掌握京津冀城市群综合承灾能力的时空分布变化规律,并制订相应的防灾策略是京津冀城市群有效应对外部冲击以及实现京津冀地区协同与高质量发展国家战略的重要支撑。

从悬置到加速:近代上海城市殡葬中的用时制度及其伦理意涵

对近代上海城市发展过程中丧葬用时变迁的梳理,分析地方丧葬向城市殡仪转变的社会成因,以及这一由科学和“进步”理念所带来的变化对现代上海殡葬体系的影响。从近代至今,上海城市丧葬实践的时间系统始终处于加速状态。自开埠以来,现代性的社会结构在上海逐渐形成,人口处于增长与流动之中,社会高度分化,社会组织各擅其事。基于汉人社会的丧葬传统,客死他乡而无力返葬的人,得到了会馆的照料,遗体依然被社会标记,保留生前的个体特殊性与社会文化属性。会馆为死去的人建立特有的社会空间,在客居者漫长的待葬过程中,地方性的文化体系得以重申,发挥着凝聚与整合的道德力量。随着近代西方公共卫生学在日常实践中的介入和社会医疗化程度的加深,关于“死去的人”的理解开始发生显著变化。在都市化进程中,人的生命被视作线性的时间过程,死亡被客观化为生物性的变化,通过技术的干预加以规范。这一在进化论和生物医学双重冲击下发生的观念变化,型塑了现当代城市丧葬实践:在人死后,死亡作为“科学”事实被快速确立,并被纳入到加速的组织流程与控制流程中。人们在快速和精细分割的丧礼过程中,如何排遣恐惧、痛苦、忧虑等面对死亡所产生的复杂情感,将成为一个需要长期观察和讨论的问题。

城市地区场次降雨时空展布方法研究

受气候变化和城市规模不断扩张等因素影响,城市地区降雨过程的时空动态性愈发明显,通常采用的点、面雨量等表达方式难以体现这种时空动态性。随着降雨观测技术的进步,大多城市积累了长序列降雨观测数据,其中蕴含了丰富的降雨时空过程信息,为预报降雨或设计降雨的时空展布提供了可能。设计了一套降雨时空展布方法,包括数据收集、标准化处理、降雨场次划分、时空模式提取、标准网格插值、时空展布等环节,并提出每个环节的处理步骤和关键问题。以北京市为例,对该技术方法进行了验证,选择了12 h、24 h、72 h 3个历时的场次降雨,提取的时空模式和展布结果表达出了场次降雨的时空动态性,并与历史的降雨过程表现出很好的匹配性。表明该方法可用于城市地区降雨典型模式提取,以及降雨过程的时空展布。该方法利用历史降雨数据提取降雨展布模板,输入场次降雨(或预报降雨)的总雨量,得到该场次降雨的时空分布过程,展布结果可为洪水预报提供更为准确的降雨输入条件。

大运河沿线省市文旅商产业融合发展研究——基于耦合协调、时空演进与发展路径分析

推动大运河沿线省市文旅商产业融合和高质量发展,是有效衔接国家重大发展战略的重要抓手。通过构建文旅商产业评价指标体系,测算大运河沿线省市2012-2020年文旅商产业耦合协调度,分析空间演化特征和影响路径。研究发现:研究期内大运河沿线省市文旅商融合水平整体呈现出逐年上升趋势;文旅商融合水平不同,且具有空间集聚性;在政策保障基础上及文旅商相关因素影响下,文旅商产业通过交叉、渗透和重组,从而实现产业协同发展形成文旅商产业综合体。因此,应采取差异化文旅商融合发展策略,以区域协同发展为基础,以大运河文化带建设为抓手,进一步推动大运河沿线省市形成全域统筹、区域协同的文旅商融合发展格局,实现大运河沿线省市经济社会文化高质量发展。

2015-2022年兰州市环境空气质量时间变化特征分析

【目的】分析兰州市环境空气质量时间变化特征,为兰州地区空气污染预报预警和大气污染防治工作提供依据。【方法】利用2015年1月1日—2022年12月31日空气质量逐小时数据,统计分析兰州市空气质量和空气质量等级日数的年际变化、月变化及日变化特征。【结果】结果表明:①2015—2022年兰州市AQI指数呈逐年下降趋势,优良天数呈增加趋势,轻度污染和中度污染天数呈减少趋势;兰州空气质量以优、良和轻度污染为主。②兰州市1—12月AQI指数呈“冬春高夏低”特征,优良天数整体呈先增后降的趋势,轻度污染和中度污染天数呈倒“U”形,12月的污染天数为最多,次峰值则出现在3月。③兰州市逐小时AQI指数呈典型的双峰特征,白天峰值出现在9时至12时,夜间峰值出现在20时至23时。【结论】研究结论可为兰州地区空气污染预报预警和大气污染防治工作提供依据。

城市空气质量指数的时间序列分析和预测--以扬州市为例

城市空气质量指数是反映城市环境宜居水平的重要指标,预测城市空气质量指数可以为政策制定提供重要的参考依据。选取扬州市2014-2022年的空气质量指数(AQI)进行时间序列分析,采用的时间序列模型有自回归积分滑动平均模型(ARIMA)、先知模型(Prophet)以及人工智能领域的长短期记忆模型(LSTM)。通过这些模型分析扬州市空气质量指数的周期性、季节性和趋势特征,并对空气质量指数进行预测。结果显示,基于人工智能的长短期记忆模型具有很强的预测能力。

数字化转型促进了企业突破式创新吗?——基于中国A股上市公司的经验证据

基于2011—2021年中国沪深A股上市公司细分专利和数字化转型数据,分别利用发明授权专利数量和质量衡量企业突破式创新水平,并通过工具变量法和多时点DID模型,实证检验数字化转型对企业突破式创新的影响效应及其内在机理。研究发现,数字化转型显著促进了企业突破式创新水平提升,且对民营企业、资本密集型企业、南方地区及沿海地区企业、高科技行业及高竞争强度行业企业突破式创新的促进作用更为显著。机制分析显示,企业突破式创新能力提升主要是由企业数字化转型带来的劳动力技能结构优化、研发强度增加及全要素生产率提高引起的。进一步以智慧城市试点作为外生冲击,发现其有效推动了数字化转型促进企业突破式创新水平的提升。基于专利质量的拓展研究发现,数字化转型与企业突破式创新质量存在显著的先抑制后促进的U型关系。上述结论为企业加快推进数字化转型,获得突破式创新提供了重要的经验证据和政策启示。

河南城市绿地10年发展规模时序变化特征分析

以城市绿地率、绿化覆盖率和人均公园绿地面积为指标,对标国家园林城市和国家生态园林城市的相关指标要求,对河南17个地级以上城市2013—2022年十年间的绿地发展规模进行研究,归纳河南城市绿地发展的时序变化特征,探索未来河南城市绿地的建设方向。