Predicting Growth of City\u27s Built-up Land Based on Scenario Planning

In this paper, method of scenario planning is applied to the study of land use planning, putting forward a new approach to analyze future growth of city\u27s built-up land in the context of future uncertainty. By introducing economic and policy factors into land use system, a calculation model of urban built-up land is built based on the correlation between industries and land use. And using Chongqing Municipality from China as an example, we establish 6 different scenarios and simulate future development of city\u27s land use from 2015 to 2020 under each scenario. The results indicate that Chongqing will meet fast urban expansion according to current trend and is in urgent need to improve its land use efficiency which shows strongest effect in controlling city size

A Self-Adjusting Approach to Identify Hotspots

Hotspot identification or detection has been widely used in many fields; however the traditional grid-based approaches may incur some problems when dealing with point database. This article expands on three types of mismatch problems in grid-based approach and suggests a point-based approach may be more suitable. Inspired by the DBSCAN algorithm, a self-adjusting approach is then proposed for hotspot detection which overcomes the weakness of parameter sensitivity shared by most clustering approaches. Finally, the data of commercial points of interest of a city is used for demonstration

Urban Growth Boundaries of the Hangzhou Metropolitan Area Based on Ecosystem Service

The identification of urban growth boundaries (UGBs) as components of an ecologically liveable city is rather significant in urban space management. However, the evaluation of ecosystem service in establishing UGBs as reactions to protect open spaces and ecological sensitive area are largely ignored. Furthermore, the lack of scenario analysis for urban growth patterns has made it difficult to adjust planning existed. Accordingly, in this paper, we take Hangzhou metropolitan areas (HMA) as the study area, using Landsat TM image data, and established the UGBs for the HMA based on ecosystem service by the Green Infrastructure Assessment (GIA) model with scenario analysis. The results suggested that: 1) The risk of urban development in the northern and eastern areas of the central city is relatively low, while the southern, eastern and south-western areas need intensive protection; 2) In the model of ecological management, the erosion of ecological space has increased gradually and the regional ecological patterns in the fourth scenarios have faced great challenges; 3) UGBs for the HMA were identified as the view of development and ecological space complementarily

Analysis of Sensory Characteristics and Aroma-Active Substances of Milk from Different Farms Using Check-All-That-Apply and Gas Chromatography-Mass Spectrometry-Olfactometry

In this study, the check-all-that-apply (CATA) method, headspace solid phase microextraction (HS-SPME)-Arrow combined with gas chromatography-mass spectrometry (GC-MS) and gas chromatography-mass spectrometry-olfactometry (GC-MS-O) were used to analyze volatile flavor substances that affect the sensory differences among milk from four pastures. The results of the CATA questionnaire showed that milky aroma, creamy aroma, fragrant and sweet aroma, milky aroma, plastic odor, cooked odor and metallic odor were significantly different among the four milk samples (P < 0.05), and milk from pasture I were the most preferred by respondents, and the preference scores of milk from pastures III and IV were lower. Totally 14 aroma-active substances with an aroma intensity greater than or equal to 1 were obtained from the four milk samples through olfactometry. Using partial least squares regression analysis (PLSR), correlation analysis among sensory data, aroma-active substances and milk samples was conducted. The results showed that milky and creamy aroma from pasture I were prominent, which was strongly correlated with 2-heptanone, butanoic acid, decanoic acid, and hexanoic acid. Milk from pasture II showed a fragrant and sweet aroma, which may be related to the concentration of limonene. Milk from pasture III had prominent metallic, plastic, and milky odors, which may be related to 1-octene-3-alcohol. Milk from pasture IV had a cooked odor, which mainly came from hexanal and styrene

Spatiotemporal Dynamic Characteristics and Causes of China’s Population Aging from 2000 to 2020

Aging involves the transformation of the population reproduction mode under the rapid development of the social economy. We studied population survey data based on the WorldPop population statistics website and used ArcGIS to construct a spatial database and implement spatial analysis methods. In this study, we analyzed the spatiotemporal evolution characteristics of population aging and its main influencing factors in counties of China, in order to provide a reference for the formulation of a national population development policy and the construction of a pension system. The results are as follows: ① The situation of population aging in China is becoming more serious, showing a point-line-area spatial pattern and two core–periphery aging patterns of high core–low periphery and low core–high periphery. ② The speed of population aging in China is characterized by rapid growth, large scale, and a high degree. Large areas of growing old before getting rich have emerged in the central and western regions. ③ The aging of the population has gradually spread to the northeast, southwest, northwest, and other regions. Influenced by factors such as population migration, population structure change, transportation facility construction, and geographic environment changes, a trend of aging that has spread across the Hu Huan-Yong line has appeared

The Impact of High-Speed Rail on Economic Development: A County-Level Analysis

High-speed rail has an important impact on the location choices of enterprises and the labor force, which is reflected in a complex space–time process. Previous studies have been unable to show the change characteristics between enterprises and the labor force at the county level. Therefore, based on the new economic geography theory, we first constructed a theoretical analysis framework to explore high-speed railway’s impact on county economy development and then obtained the two economic subdivision factors’ impacts: industrial enterprises and secondary labor force. Then, based on the panel data of 1791 county units in China from 2003 to 2019, the study constructed a multi-period PSM-DID model to empirically explore high-speed rail’s impact on the county’s agglomeration of industrial enterprises and secondary labor force. The results show that high-speed rail has a long-term negative effect on the county area’s agglomeration of industrial enterprises. From the perspective of the labor force, high-speed rail has a long-term and continuous positive effect on the agglomeration of the secondary labor force in county units

National Land Use Management in China: An Analytical Framework

ABSTRACT: Rapid urban land growth has been a major characteristic of urbanization in China since reform and open-door policies began in the late 1970s. Due to its unique political system, historical experience, and geographic conditions, urban land growth in China is still characterized by short periods of land acquisition, large-scale land development, and large-scale industrial use. Although urban land use is basically a local issue for cities, many important policies are also framed by the Chinese central government to ensure that national interests are protected.Following a review of urban land growth in China, this study found that the role of the central government in urban land growth has been changing in recent years. The once exclusive objective of ensuring urban economic development has been replaced by multi-objective considerations of economic, social, and environmental issues, addressing both urban and rural interests in the process of urban land growth. This transition has also greatly influenced the policies of city governments, which has in turn influenced local land use patterns. However, attaining these multiple objectives is becoming increasingly difficult. This paper examines the underlying causes of this shift and discusses various approaches to adjusting the future role of the central government. KEYWORDS: National land policy, garbage can, game theory, Chi

Decision Network: a planning tool for making multiple, linked decisions

Few techniques exist specifically for planning analysis. Commonly used decision techniques focus on different, partial aspects of coordinating decisions. The garbage-can model focuses on the context in which decisions emerge to explain descriptively how organizational choices are made; the strategic choice approach focuses on the relationship between decisions from which rational actions can be taken; and the decision tree focuses on the causal sequence of decisions from which the optimal path of a plan can be derived. Drawing on the theoretical foundation of these three commonly used techniques, we introduce the conceptual framework of a tool for planning analysis, namely Decision Network , that addresses context, relationship, and sequence of decisions, with a numerical example demonstrating how the decision problem can be formulated and solved. Decision Network can be used by decision makers who are faced with more than one decision in order to make plans. Much can be built on this tool to address spatial issues.