Electrical Characteristics of Tangjiawan Landslide in Lixian, Sichuan

A wide range of terrain features and landforms,which are exemplified by intricate geological formations and diverse rock compositions,are found in the western mountainous regions of China.These areas frequently encounter geological disasters.As one of the natural disasters,landslides lead to considerable loss of human life and property.Considering mitigation of the losses caused by landslide disasters,a necessary measure for disaster prevention and mitigation involves conducting detailed investigations and monitoring of landslides,which is also the cornerstone of landslide warning.This study compares and analyzes the feasibility of the magnetotelluric detection method for landslides using the results of engineering geological surveys and landslide monitoring.The study aims to address the scientific problem of the validity of using magnetotelluric methods to detect landslide development processes.The Tangjiawan landslide signal on the left side of the K94+000~K94+145 section of the Wenma Expressway is analyzed by employing engineering geological survey,magnetotelluric detection,landslide monitoring,landslide analysis,and other methods.Analysis results provide the static electrical characteristics of lithology,structure,and groundwater,as well as the dynamic electrical characteristics of landslide development.This study focuses on analyzing the relationship between the methods of magnetotelluric detection and engineering geological surveys and the results of landslide monitoring.The workflow and methods for data collection,processing,inversion,interpretation,and analysis using the magnetotelluric method to detect the dynamic development process of landslides are presented in the conclusion.Preliminary conclusions indicate a strong correlation between the dynamic changes in magnetotelluric wave impedance with the surface displacement of landslides and the dynamic changes in groundwater.The use of the magnetotelluric method for landslide detection and monitoring is a feasible example.The research results can offer certain technical references for the detection and monitoring of landslides using magnetotelluric methods and also provide references and guidance for the selection of diversified landslide monitoring methods in the future.

崇高人性的追求 幸福生活的归宿——《工地上的女人》主题意蕴阐释

影片《工地上的女人》是一部反映女性农民工在都市生活的婚恋作品。从主人公追求做人的尊严意识的深化;在金钱和爱情之间的两难抉择;逃离都市,回归乡土等三个方面可以看出主人公对崇高人性的追求和寻找幸福生活归宿的愿望。

平凡中的诗意之美：《工地上的女人》

故事梗概： 小军是一个从河北乡下到北京来投奔表哥林大地的农村青年，他满怀着对城市的向往和憧憬，在表哥介绍的建筑工地上开始了梦想中的城市生活。在工地上，小军熟识了在工地开杂货铺的女人玉兰。玉兰是包工头杜昆的女人，她依靠着杜昆的势力在工地上以小本买卖为生，并从中偷偷积蓄。

工地屋檐下那个燕子窝……

4月，省会沉醉在春天之中．空气难得的清新。天空难得的湛蓝，下班的路上，忽见几只燕子在楼群中翻飞，心中不由泛起丝丝喜悦。因为，这让我想起在黄壁庄水库除险加固工地办公楼屋檐下的那个燕子窝……

工地安全员（诗）

每天，从黎明到黄昏你的脚步。

Prediction of rockburst classification using Random Forest

The method of Random Forest （RF） was used to classify whether rockburst will happen and the intensity of rockburst in the underground rock projects. Some main control factors of rockburst, such as the values of in-situ stresses, uniaxial compressive strength and tensile strength of rock, and the elastic energy index of rock, were selected in the analysis. The traditional indicators were summarized and divided into indexes I and 1I. Random Forest model and criterion were obtained through training 36 sets of rockburst samples which come from underground rock projects in domestic and abroad. Another 10 samples were tested and evaluated with the model. The evaluated results agree well with the practical records. Comparing the results of support vector machine （SVM） method, and artificial neural network （ANN） method with random forest method, the corresponding misjudgment ratios are 10%, 20%, and 0, respectively. The misjudgment ratio using index I is smaller than that using index II. It is suggested that using the index I and RF model can accurately classify rockburst grade.

Rural Domestic Wastewater Treatment through Anaerobism and Artificial Wetland

[ Objective] The study aimed to test capacity of sewage treatment with anaerobic ＋ artificial wetland. [ Method] By studying on the removal of conventional pollutants such as CODcr, SP, TP and NH4^＋-N with new wetlands, their impact on the capacity of sewage treatment. [Resuit]The CODcr removal efficiency could reach 70% -80% and the value of CODcr could be reduced from above 300.00 mg/L to blow 100 mg/L, the removal efficiency of SP and NH4^＋-N was 30% -40% when hydraulic load is 90 crn/d. [ Conclusion] When the concentration of CODcr, SP and NH4^＋ -N were below 300.00,2.50 and 15.00 mg/L, it＇s easy to achieve a more stable removal efficiency.

Research Progress on Application of Constructed Wetland in Wastewater Treatment in China

Constructed wetlands as a wastewater eco-treatment technology has devel-oped for decades. Combining wastewater-treatment with water recycle in an efficient way, it plays an important role in water body restoration and ecological construction. Constructed wetlands with unique advantages have attracted intensive attention since it developed, and have been widely used in treatment of domestic sewage, industrial wastewater, and mine wastewater. In this paper, we summarized the clas-sification, composition, combination, operation mode and pol utant removal mecha-nism of constructed wetlands, as wel as the research progress on the application of constructed wetland in wastewater treatment at home and abroad. In addition, in view of the problems of using constructed wetlands to treat wastewater in China, corresponding solutions were put forward, including setting up system construction standards for constructed wetlands, developing the regulatory and enhancing tech-niques of nitrogen and phosphorus removal, and taking advantage of the unique features of constructed wetlands to improve and restore ecological environment.

Electricity generation during wastewater treatment by a microbial fuel cell coupled with constructed wetland

A membrane-less constructed wetland microbial fuel cell （CW-MFC） is constructed and operated under continuous flow with a hydraulic retention time （HRT） of 2 d. Fed with glucose, the CW-MFC generates a stable current density of over 2 A/m3 with a resistor of 1 kΩ and has a chemical oxygen demand （COD） removal efficiency of more than 90% after the startup of 2 to 3 d. A series of systems with the electrode spacings of 10, 20, 30 and 40 cm are compared. It is found that the container with the electrode spacing of 20 cm gains the highest voltage of 560 mV, the highest power density of 0. 149 W/m 3, and the highest Coulombic efficiency of 0.313%. It also has the highest COD removal efficiency of 94. 9%. In addition, the dissolved oxygen （DO） concentrations are observed as the lowest level in the middle of all the CW-MFC reactors. The results show that the more COD is removed, the greater power is generated, and the relatively higher Coulombic efficiency will be achieved. The present study indicates that the CW-MFC process can be used as a cost-effective and environmentally friendly wastewater treatment with simultaneous power generation.

Design of Constructed Wetland for Treatment of Tailwater from Wastewater Treatment Plant

In this study, the project of constructed wetland for treatment of tailwater from the wastewater treatment plant in Wudang Mountain was taken as an example, and the technological processes, pollution load, wetland bed structure, bed filler, selection of plants and hydraulic conditions of the subsurface flow constructed wetland were discussed. A subsurface flow constructed wetland, which covered an area of 7 227 m^2 was finally designed. It could treat 7 000 m^3 of tailwater from the wastewater treatment plant a day. In addition, the system could reduce the emission of COD, BODs, TN, TP and NH3-N by 25.55, 25.55, 12.78, 1.28 and 17.89 t respectively a day. The outlet water was proved to reach the Standard A of the first class in Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant （GB 18918-2002）.

Design and Implementation of Biogas Plants Geographic Information System

[Objective] A kind of biogas engineering geographic information system was designed and realized.[Method] Based on the data of the investigation of the large and medium-sized biogas projects in Beijing,the system user＇s need and function demand were studied.Sub-system function was divided.By using SuperMap IS.NET,C# and SQL Server 2005 as the database and WebGIS frame,the system spatial and attribute database were designed so as to realize the WebGIS software of biogas project in Beijing.[Result] The system provided application platform for the distribution of biogas project information.User can realize the submission and inquiry the feedback of biogas project information based on system application right etc,so as to visually,fully and precisely inquiry project data.Based on the comprehensive analysis of data,the current state of biogas project and change trend were studied and decided.[Conclusion] The system provided convenience and services to relevant departments＇ planning and management of biogas project.

Study on Qianling Lake Restoration with Artificial Wetland

The ecological restoration of water quality in Qianling Lake was conducted by artificial wetland, which transformed N and P in wastewater into essential matters in organism tissues, so pollutants discharged into Qianting Lake were reduced for the purpose of restoration.

Influential Factors of House-purchasing Intention in Work construction Sites among Migrant Workers with a Case of Investigations on 203 Migrant Workers from Jiangxi Province

The research selected 13 factors from individual and family characters, construction site characters and work characters and analyzed the influences on the willingness of purchasing houses on construction sites with Logistic regression mod- el. The results showed that gender, age differences, personality, willingness on fami- ly land conversion, management of enterprises on construction sites, relatives and friends on construction lands, and Job satisfaction were approved by significant testing, but marital status, annual household income, the rate of migrant worker in a household, transportation in work city, and corporate reputation were not approved by significant testing.

The Role of Coix lacryma-jobi Linn. in Wastewater Treatment System of Constructed Wetland

The dynamic of growth and nutrient （N and P） absorption of Coix lacryma-jobi Linn.in constructed wetland （CW）,as well as the effect of constructed wetland harvest on N,P absorption in eutrophic water were studied.The results revealed that,in Summer and Autumn,especially in August,C.lacryma-jobi could obtain higher biomass and N,P accumulations,thereby achieving the most efficient purification; from the breeding value point of view,N,P contents could be improved by the appropriate increase of harvest times of C.lacryma-jobi,while too many harvest times was inappropriate to the wastewater purification by C.lacryma-jobi and the nutrients accumulation.So,C.lacryma-jobi should be harvested completely in August during its growth period,and twice-3 times of harvests was appropriate.

Study on the Floating Plant Climatic Adaptation of Undercurrent Constructed Wetland in North China

[Objective] The aim was to choose appropriate floating plant in the wetland in the north China.[Method] Pistia stratiotes L.,Eichhornia crassipes,and Hydrocharis dubia（Bl.） Backer were planted in the aquatic biological pool of constructed subsurface flow wetland system in the reservoir.Through filed investigation,the growth of the three kinds of plants was studied and their adaptability to the northern climate was concluded.[Result] Judging from the growth speed and state of the three kinds of floating plants,the biological characteristic of Pistia stratiotes L.can perfectly adapt the environment in the pool in the reservoir,followed by the Eichhornia crassipes.The growth state of the Hydrocharis dubia（Bl.） Backer was the worst one and it can not adapt to the north environment.[Conclusion] It provided references for the choice of artificial floating plant in the north area.

Influence of Perforation on Formation Fracturing Pressure

Hydraulic fracturing treatments of oil wells are greatly affected by the perforation parameters selected. The three-dimensional finite element model together with the tensile criterion of rock materials is employed to systematically investigate the influence of perforation parameters, such as perforation density, perforation orientation, perforation diameter, and perforation length as well as wellbore ellipticity, in vertical wells on the formation fracturing pressure. Based on a six-month simulation research in the University of Petroleum, China, several conclusions are drawn for the first time. Perforation density and perforation orientation angle are the most important parameters controlling the formation fracturing pressure. As the perforation density increases, the fracturing pressure decreases, not linearly but progressively. The fracturing pressure increases with the perforation orientation angle only when the angle is less than 45 degrees, and the relationship becomes very flat when the angle is 45 degrees. However, with regards to the perforation diameter and perforation length, their influences are much slighter. The wellbore ellipticity has a significant effect on the formation fracturing pressure. It is obvious that fracturing pressure increases linearly with the ellipticity of the wellbore.

Microbial Distribution in Constructed Wetland of Iris pseudacorus L.

[Objective] The aim was to explore the distributions of main microorganisms in constructed wetland of Iris pseudacorus L.and their function and position in wastewater treatment.[Method]Distributions of main microorganisms in the upstream vertical-flow constructed wetland of Iris pseudacorus was studied by training and observing 4 kinds of microorganisms.[Result]The total number of microorganisms on root surface in unit area was 15.32 times as many as that on filler surfacein,among them bacteria and actinomycete were 17.14 times and 19.84 times as many as those on filler surfacein,respectively.[Conclusion]The distributions of microorganisms are significantly different in different parts of wetland system,obviously on root surface.Bacteria are the main populations of biological wastewater treatment.

Activities of Urease and Phosphatase in Integrated Vertical Flow Constructed Wetland and Purification Effect of Black and Malodorous River

[Objective]The activities of urease and phosphatase in integrated vertical flow constructed wetland and purification effect of black and malodorous river were studied.[Method]Honeycomb stone and soft filler were used as matrix,the biological grid integrated vertical flow constructed wetland system was built to strengthen treatment for black and malodorous river,and the activities of urease and phosphatase of two fillers in different functional areas of constructed wetland were tested to study the film formation property of two fillers in different functional areas.[Result]Both urease and phosphatase activities on biofilm of soft filler were significantly higher than on biofilm of honeycomb stone filler;indicating that choosing soft filler was more advantageous to the growth of biofilm;and urease activity had significant correlation with total nitrogen removal rate,while phosphatase activity had no significant correlation with total phosphorus removal rate.[Conclusion]This study provided evidences for utilizing the activities of urease and phosphatase to evaluate the purification effect of black and malodorous river and choose appropriate filler.

Treatment of Domestic Sewage by Channels Constructed Wetland in New Countryside

[Objection] The aim was to study application of channels constructed wetland in treatment of domestic sewages in new countryside. [Method] Supported by construction of new rural areas project in China, we surveyed on new rural areas in Gannan, Jiangxi Province, summarized source, characteristics and treatment of domestic sewage in countryside, and designed channels constructed wetland for sewage treatment. [Result] The technique is proven effective in sewage treatment. After the technique was conducted for a trial run for four months, removal rates of COD, TP and TN averaged 73.07%, 73.25% and 72.36%, respectively. After contin- uous sampling for six times, effluent COD was analyzed 20-35 mg/L, TP was 0.60- 1.19 mg/L and TN was 6.88-11.21 mg/L, better than that of Standard 1B ruled by Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant. [Conclusion] Thanks for low investment, channels constructed wetland can be built by trans- formation of bottom land, proving a good way for treatment of diffuse pollution source and control of water non-point pollution.

Influence of land use characteristics and trip attributes on commuting mode choice: a case of Nanjing

The effects of socio-demographics, land use characteristics and trip attributes on the commute mode choice are studied with a nested logit （NL） model. Based on the random utility maximum theory, the NL model is formulated. The analysis is carried out in the main area of Nanjing. Direct and cross elasticities are calculated to analyze the effects of travel time and travel cost on the selection of travel mode choice. The results reveal that the non-motorized travel modes are more attractive in the areas with higher housing and employment accessibility and car owners are found to be more likely to commute to work by car. The bus and subway choice probabilities are more sensitive to changes in travel times than to changes in travel costs. In conclusion, a comprehensive public transit system and effective integration of land use and transportation policies help to relieve the traffic congestion levels caused by the increasing urban sprawl.