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Search Results: 1 - 10 of 20166 matches for " Chunyan Chang "
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Characteristics and Spatial Variability of Saline-Alkaline Soil Degradation in the Typical Yellow River Delta Area of Kenli County, China  [PDF]
Zhuoran Wang, Gengxing Zhao, Mingxiu Gao, Chunyan Chang, Jichao Jia, Jin Li
Journal of Environmental Protection (JEP) , 2014, DOI: 10.4236/jep.2014.512104
Abstract: As an important area of reserve land resources, the Yellow River Delta is faced with the problem of soil salinization. Grasping the characteristics of soil salinity as well as its spatial variation patterns is an important foundation of prevention, control and utilization of saline soil. This study selected Kenli County of the Yellow River Delta, obtained soil salinity data through field survey and lab experiment, and used statistical, GIS interpolation and buffer analysis methods to analyze the characteristics of soil salinity and its spatial variation patterns. Our results showed that the general soil salinity in the study area was mainly moderate and there was a significant positive correlation between different soil layers of 0 - 15 cm, 15 - 30 cm and 30 - 45 cm and soil salinity increased with the increase of soil depth. The areas with high soil salinity in each soil layer mainly distributed in the east near the Bo Sea in the county, while the areas with lower soil salinity mainly distributed in the southwest, centre and the two sides of the Yellow River in the northeast. Soil salinity showed a trend of decrease with the increase in distance to the Bo Sea, while stretching from the Yellow River, it showed increase tendency with the increase in distance to the Yellow River. The order from high soil salinity to low of different vegetation types was naked land → suaeda glauca → tamarix → vervain → reed → couch grass → paddy → cotton → winter wheat → maize; the order for different geomorphic types was depression → slightly sloping ground → slow hillock → high flood land. This study preliminary delineated the characteristics of soil salinity as well as its spatial variation patterns in the study area, and provided scientific basis for soil resource sustainable utilization in the Yellow River Delta.
Information Extraction Method of Soil Salinity in Typical Areas of the Yellow River Delta Based on Landsat Imagery  [PDF]
Tongrui Zhang, Gengxing Zhao, Chunyan Chang, Zhuoran Wang, Ping Li, Deyu An, Jichao Jia
Agricultural Sciences (AS) , 2015, DOI: 10.4236/as.2015.61006
Abstract: In order to get RS method to extract soil salinity of the Yellow River Delta, we set Kenli County as typical Yellow River Delta to be research area and get data of soil salinity through field investigation. By using RS image of Landsat-8 of March 14, 2014 and analyzing information features of each band and surface spectral features of research areas, we select out sensitive bands and build Soil Salinity Information Extraction (SSIE) model and vegetation index NDVI model for comparison. And then, we accordingly classify grades of soil salinity and get soil salinity information by decision tree approach based on expert knowledge. The results show that overall accuracy of SSIE model is 93.04% and coefficient of Kappa is 0.7869, while overall accuracy of NDVI model is 83.67% and coefficient of Kappa is 0.7017 respectively. By comparing with measured proportions of each class, we see that results from SSIE model is more accurate, which indicates significant advantage for soil salinity information extraction. This research provides scientific basis to get and monitoring soil salinity of the Yellow River Delta region quickly and accurately.
Mechanism Research on PM2.5 Charging, Precipitation in High Electrostatic Field  [PDF]
Jingcai Chang, Chunyan Xu, Aiping Tao, Mingfeng Gao, Xiang Wang, Chunyuan Ma
Journal of Environmental Protection (JEP) , 2015, DOI: 10.4236/jep.2015.61002
Abstract: In this project, some charged characteristics, and analysis of precipitated PM2.5 in high electrostatic field were calculated based on theories and experiments. The connection between the charge amount and the additional electric field intensity caused by the wet flexible collectors was studied to reveal the mechanism of charging enhancement of PM2.5 on flexible collectors. Some explanation about the wet ability of collectors and the current density enhancing the precipitation process was proposed in this project. Simultaneously, the results shows that both gas treatment time and applied voltage have an important influence on particle collection, and the minor factor was initial concentration.
Wetting Characterization of Hybrid Coatings Deposited on Carbon Steel Collectors for Hydrophilic Modification  [PDF]
Chunyan Xu, Jingcai Chang, Jiaqiu Song, Xiang Wang, Bo Zhang, Lin Cui, Chunyuan Ma
Journal of Environmental Protection (JEP) , 2015, DOI: 10.4236/jep.2015.612119
Abstract: The additional anticorrosive coating and hydrophilic layer of glass fiber cloth (GFC) deposited on the carbon steel sheet (CSS) was experimented and the surface wetting characteristic of the hydrophilic modified collection electrode was investigated under single strand feed water condition. The distilled water was selected as the working fluid. The influence of Reynolds number on the surface wetting characteristic parameters and those parameters at different temperatures were specifically studied. The results indicate that the GFC surface with loose glass fiber bundles reveals remarkable surface wetting characterizations. The saturated liquid holdup of this surface is 8 - 10 times more than that of the CSS surface; the surface flowrate value is 6 - 8 percent of that of the CSS surface; the film rate of this surface is 28 - 32 times more than that of the CSS surface; the average film thickness is between a third and a half of the value of the CSS surface. Good agreement is achieved between the WESPs working temperature and the experimental temperature range with remarkable wetting characterizations that provides a theoretical basis for the industrial application. Not satisfactorily, the hydrophilic modification surface is not able to survive high temperature.
Estimating Total Nitrogen Content in Brown Soil of Orchard Based on Hyperspectrum  [PDF]
Shujing Cao, Xicun Zhu, Cheng Li, Yu Wei, Xiaoyan Guo, Xinyang Yu, Chunyan Chang
Open Journal of Soil Science (OJSS) , 2017, DOI: 10.4236/ojss.2017.79015
Abstract: The best hyperspectral estimation model of soil total nitrogen (TN) was established, which provided the basis for rapid and accurate estimation of soil total nitrogen content, scientific and rational fertilization and soil informatization management. A total of 92 brown soil samples were collected from the orchard of Qixia County, Yantai City, Shandong Province. After drying and grinding, the hyperspectrum of the soil was measured in the laboratory using ASD FieldSpec3. The TN contents of brown soil were measured by Kjeldahl method. The sensitive wavelengths were selected by multiple linear stepwise regression method. The hyperspectral estimation model of TN was established by Random Forest (RF) and Support Vector Machines (SVM). The models were validated by independent samples. The best estimation model was obtained. The sensitive wavelengths were 956 nm, 995 nm, 1020 nm, 1410 nm, 1659 nm and 2020 nm. The coefficients of determination (R2) of the two estimation models were 0.8011 and 0.8283, the root mean square errors (RMSE) were 0.022 and 0.025, and relative errors (RE) were 0.1422 and 0.1639, respectively. Random Forest model and Support Vector Machines model are feasible in estimating TN contents, but the Support Vector Machines model is better.
Applications of Hyperspectral Remote Sensing in Ground Object Identification and Classification  [PDF]
Yu Wei, Xicun Zhu, Cheng Li, Xiaoyan Guo, Xinyang Yu, Chunyan Chang, Houxing Sun
Advances in Remote Sensing (ARS) , 2017, DOI: 10.4236/ars.2017.63015
Abstract: Hyperspectral remote sensing has become one of the research frontiers in ground object identification and classification. On the basis of reviewing the application of hyperspectral remote sensing in identification and classification of ground objects at home and abroad. The research results of identification and classification of forest tree species, grassland and urban land features were summarized. Then the researches of classification methods were summarized. Finally the prospects of hyperspectral remote sensing in ground object identification and classification were prospected.
Perspective of Problems and Countermeasures by the Analysis of the Collection Data on the Personal Income Tax Collection and Administration of High Income Groups  [PDF]
Chunyan Pan
Open Journal of Social Sciences (JSS) , 2015, DOI: 10.4236/jss.2015.310018
Abstract: In recent years, the collection and administration of personal income tax of high income groups have always been the emphasis and difficulty of the tax authority. This article analyzes the personal income tax collection and management data of GZ city Y area local taxation bureau, and finds that the current tax authorities on the personal income tax levy management have some problems, such as the individual income tax of the total amount of wages and salaries accounts for a large proportion of the total individual income tax, and it is difficult to regulate the individual business production and operation income and labor remuneration income, and the number of foreign individuals hidden income rise, etc. The working practice is also connected to discuss and analyze the above problems, putting forward many measures to establish and improve the system of tax assessment, building effective network for assistance and protection of tax, strengthening the collection and management of various income taxes, establishing individual tax registration system and personal bank account system, reinforcing audit and penalties and so on.
The Approach of Accounting Information Quality on Investment Efficiency—Empirical Evidence from Chinese Listed Companies  [PDF]
Chunyan Ren
Theoretical Economics Letters (TEL) , 2016, DOI: 10.4236/tel.2016.62037
Abstract: This paper studies the approach of accounting information quality on investment efficiency, from the context of the Chinese reality system. The empirical results confirm that the proxy for accounting information quality is negatively associated with over-investment or under-investment. Furthermore, there is a negative association between the quality of accounting information and the future investment for firms classified as over-investment and a positive association between the quality of accounting information and the future investment for firms classified as under-investment. The results suggest that the improvement of accounting information quality helps to restrict companies from over-investment and helps the companies to mitigate under-investment.
An Analysis of Differences between English and Chinese Tourism Texts  [PDF]
Chunyan Yao
Open Journal of Modern Linguistics (OJML) , 2019, DOI: 10.4236/ojml.2019.93015
Abstract: In the context of globalization, tourism serves as an increasingly important bridge in the mutual understanding among different countries. Tourism literatures transmit adequate information about tourist destinations with an aim to evoke readers’ interests to have a visit. Well-translated tourism texts help a lot in attracting overseas tourists. Therefore, it is of great importance to equip translators with the awareness of the major differences between Chinese and English tourism texts in order to make the targeted texts informative, acceptable and attractive to the targeted readers. The two chief differences, discourse structures and persuading approaches in particular, are explored in this essay. In terms of discourse structures, English tourism texts stress hypotaxis and develop linearly in the way of deduction, while Chinese texts emphasize parataxis and develop spirally in an inductive way. As for persuading approaches, concise and objective descriptions are common in English texts, but Chinese tourism literatures normally turn to flowery expressions and parallel structures, quotations as well as rhetoric devices to realize the vocative function.
Classifying Traveling Wave Solutions to the Zhiber-Shabat Equation  [PDF]
Chunyan Wang, Xinghua Du
Journal of Applied Mathematics and Physics (JAMP) , 2013, DOI: 10.4236/jamp.2013.12001
Abstract: By the complete discrimination system for polynomials, we classify exact traveling wave solutions to the Zhiber-Shabat equation, and compute some new traveling wave solutions.
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