Distribution Characteristics of Spermophilus dauricus in Manchuria City in China in 2015 through ‘3S' Technology

Plague is a virulent infectious disease in China. In this study, ＇3S＇ technology was used to perform spatial autocorrelation analysis and spatial interpolation analysis for Spermophilus dauricus （S. Dauricus, a species of ground squirrel） captured in Manchuria City in 2015. The results were visually inspected. During the two-month （May to July） plague surveillance in 2015, 198 S.

Gini Index for Cities: A Preliminary Study on Regional Differences of Chinese City Size Distribution

City size distribution is of interest because of a number of key stylized facts, including notably Zipf's law for cities and the importance of urban primacy. But a new and more efficient method Gini index can be used for calculating regional city size distribution. This paper begins by developing a calculation method for the Gini index, dividing the whole country into 26 areas and then calculating each area's Gini index value. Based on these calculation results, this paper gives a preliminary study on regional differences of its city size distribution and the dynamics.

Distribution of primary school based on spatial network comprehensive model in low-income mountainous cities： a case study in Wanyuan, China

Focusing on the peculiarities of urban construction resulting from specific mountain terrains, the purpose of this study is to find out a suitable method based on a Spatial Network Comprehensive Model(SNCM) to reasonably plan and distribute primary schools in low-income mountain cities. The construction principles and advantages of the SNCM method are proposed and the method tested in Wanyuan city of Qinba Mountain area(Southwest China) to verify its feasibility and optimization. Taking account of the mountain terrain and its influence on user behavior, we used the SNCM method to build a comprehensive model which integrates the road slope and the walking speed of pupils into the basic spatial model. The model is used to calculate a reasonable layout of the primary schools and to validate the rationale. The results show that the SNCM method can be effectively applied in low-income mountainous cities. It can not only improve the accessibility and service efficiency of primary schools using as little capital-investment as possible, but also help the city grow in an intensive and efficient way.

Modeling parameters influencing city gas distribution sector based on factor analysis method

City gas distribution(CGD)sector is influenced by several factors like policy,infrastructure,health,safety etc.In order to understand this sector,an exploratory factor analysis is conducted.The Exploratory Factor Analysis(EFA)survey meticulously simplifies interconnected steps and examines the possible causal factor structure of a series of measured variables without hitting a predetermined result model.In this paper,the factor analysis is performed in three broad categories namely:managerial level,technical level and site workers to understand the most influencing factor of the sector.60 questionnaires were prepared to get feedback on parameters affecting CGD sector.The survey is performed by various means,like google form,email,phone calls,appointments with employees and personal meetings.It has been observed from the survey that the nine factors influences this sector and requires certain modifications for the development.Out of these nine factors,five were selected for the analysis which are infrastructure factor,policy factor,gas consumption factor,total energy demand factor and economy factor.The factor analysis has been performed in five major steps,namely factor analysis applicability,selection of factors,loading of factors,significance test of factors and factor loading matrix analysis.The results obtained from these exploratory factor analysis shows that variables like infrastructure,total energy demand and economy affects the CGD market most than the policy and gas consumption.

Fundamentals and developments of compressed biogas in city gas distribution network in India:A review

Biogas is a significant renewable source as well as an alternative energy carrier provided by Anaerobic Digestion(AD)of biodegradable food wastes and other organic materials.This paper describes some major facts about biogas along with the barriers and adaptation of CBG in society,it also narrates the types of feedstocks available for biogas generation and what are the major sources in India.In this study,different stages of anaerobic digestion are discussed such as hydrolysis,acidogenesis,acetogenesis and methanogenesis for biogas production.After its purification,the biogas can be used as a fuel for domestic as well as transportation purposes.A glimpse of biogas like purification techniques like biological desulphurization,iron chloride dosing,pressure swing adsorption,chemical scrubbing and water scrubbing is given,the major additions of national policy of biofuels in 2018 is also highlighted.It has been found that in India,majorly pressure swing adsorption and water scrubbing methods are used for biogas purification,currently,the country has 12 commercial CBG plants with a total CBG output capacity of 18,461.7 tonnes per year,which is just 0.06 percent of the total ability.The details of the plants along with their CBG production capacity are described,and sustainable alternative towards affordable transportation(SATAT)launched by MoPNG is introduced in this study,furthermore,the features and types of models suggested by Ministry of Petroleum and Natural Gas(MoPNG)to introduce compressed biogas(CBG)in city gas distribution(CGD)network are discussed.

Sequential city growth： Theory and evidence from the US

City growth patterns are attracting more attention in urban geography studies. This paper examines how cities develop and grow in the upper tail of size distribution in a large-scale economy based on a theoretical model under new economic geography framework and the empirical evidence from the US. The results show that cities grow in a sequential pattern. Cities with the best economic conditions are the first to grow fastest until they reach a critical size, then their growth rates slow down and the smaller cities farther down in the urban hierarchy become the fastest-growing ones in sequence. This paper also reveals three related features of urban system. First, the city size distribution evolves from low-level balanced to primate and finally high-level balanced pattern in an inverted U-shaped path. Second, there exist persistent discontinuities, or gaps, between city size classes. Third, city size in the upper tail exhibits conditional convergence characteristics. This paper could not only contribute to enhancing the understanding of urbanization process and city size distribution dynamics, but also be widely used in making effective policies and scientific urban planning.

Aerosol size distributions during haze episodes in winter in Jinan, China

Number concentrations and distributions of 10-10,000 nm particles in a large city （Jinan） in the North China Plain were measured in winter 2009. The mean number concentrations of nucleation mode （10-20 nm）, Aitken mode （20-100 nm）, and accumulation mode （100-1000 nm） particles, as well as total particles were 925, 6898, 2476, and 10,299cm-3, respectively. Two severe haze episodes, with elevated concentrations caused by pollutants accumulating, were observed. Accumulation mode particle concen- trations were significantly higher during the episodes than on clear days, and nucleation mode particle concentrations were pronouncedly higher on clear days than during the episodes. The peaks of domi- nant number, surface area, and mass size distributions were around 30-50, 200-300, and 200-400 rim, respectively, both during the haze episodes and on clear days, but elevated mass and surface area con- centrations around 500-600 nm were also observed during the haze episodes, suggesting these particles had significant contributions to haze formation. These particles were probably formed through larger droplets in cloud and fog evaporating. Two new particle formation events, probably triggered by strong photochemical processes on clear days and significant traffic emissions during haze episode 2, were found. Significant insights were made into haze formation in a oolluted Chinese urban area.