[Objective] The aim was to research macrobenthos community structure and its relations with environmental factors in three reservoirs. [Method] Benthic diversity and water quality of Yuqiao Reservoir, Beidagang Reserv...[Objective] The aim was to research macrobenthos community structure and its relations with environmental factors in three reservoirs. [Method] Benthic diversity and water quality of Yuqiao Reservoir, Beidagang Reservoir and Er- wangzhuang Reservoir were investigated in May, July and September 2011, respec- tively. []Result] Of all the 14 sampling sites, 22 species of macroinvertebrates were collected, totally, which included 6 species of aquatic insects, 7 species of Mollusca, 2 species of Crustacean, 7 species of Oligochaeta. The species of macroinverte- brates during May, July and September in Yuqiao reservoir were 11, 8 and 10, respectively. The dominant species were Chironomus sinicus, and Monopylephorus limosus. The average density and biomass of the macrobenthos were 132.43 ind./m2 and 50.09 g/m2. Yuqiao reservoir was mostly at status of premediate polluted, according to the Margalef index, Shannon index and Pielou index. The species of during May, July and September in Beidagang reservoir were 5 5 and 5, respectively. The dominant species were Chironomus sinicus, Penaeus vannamei. The average density and biomass of the macrobenthos were 218 ind./m2 and 2.70 g/m2. Beidagang reservoir was mostly at status of heavy polluted, accord- ing to the Margalef index, Shannon-wiener index, Pielou index. The species of during May, July and September in Erwangzhuang reservoir were 3, 5 and 5, respectively. The dominant species were Monopylephorus limosus, Chi- ronomus sinicus. The average density and biomass of the macrobenthos were 104 ind/m2 and 0.20 g/m2. Erwangzhuang reservoir was mostly at status of intermediate polluted, according to the Margalef index, Shannon index, Pielou index. The density of zoobenthos in Yuqiao Reservoir was positively significantly correlated with TP (P〉 0.05), negatively correlated with NH4+-N (P〉0.05), positively correlated with COD (P〈 0.01), not significantly correlated with other environment factors (P〉0.05). There was no significant correlation between biomass of zoobenthos and environment factors. The density of zoobenthos in Beidagang Reservoir with NH4+-N was positively signif- icantly correlated (P〈0.05), not significantly correlated with other aquatic environment factors (P〉0.05). There was no significant correlation between biomass of zoobenthos and environment factors. The density of zoobenthos in Erwangzhuang Reser- voir with NO3-N was positively significantly correlated (P〈0.05), not significant cor- related with other aquatic environment factors (F〉0.05). The biomass of zoobenthos in Erwangzhuang Reservoir with NH4+-N was positively significantly correlated (P〈 0.05), not significant correlated with other aquatic environment factors (P〉0.05). [Conclusion] It is indicated that this three reservoirs were all eutrophied and polluted, and the eurephication extent change of water in three reservoirs is as follows: Beidagang reservoir〉Erwangzhuang reservoir〉Yuqiao reservoir.展开更多
The collector managed inventory(CMI)management idea is introduced based on the comparison of manufacturer and third-party logistics(3PL)implementing vendor managed inventory(VMI)services.Considering recovery costs,the...The collector managed inventory(CMI)management idea is introduced based on the comparison of manufacturer and third-party logistics(3PL)implementing vendor managed inventory(VMI)services.Considering recovery costs,the service pricing strategies for 3PL corporations implementing VMI are studied to meet two conditions of participation constraints and incentive-compatibility constraints.The numerical simulation results indicate that the supply chain partners' profits change after considering recovery costs,and the 3PL corporation's profits and the total profits increase first,and then decrease.The retailers' and manufacturers' profits also increase.The total profits of the supply chain have a characteristic of increasing first and then decreasing with the increase of the callback ratio of unsold products.The concrete extremum point is codetermined by price flexibility,service pricing of the 3PL corporation,callback price and callback ratio.展开更多
This paper has 4 parts. Part 1 presents a comparative analysis of think tank evaluation methods. Part 2 introduces the AMI index system for comprehensive evaluation of global think tanks. Part 3 describes the current ...This paper has 4 parts. Part 1 presents a comparative analysis of think tank evaluation methods. Part 2 introduces the AMI index system for comprehensive evaluation of global think tanks. Part 3 describes the current situation of global think tanks based on ranking by AMI. Part 4 proposes the construction of new type think tanks with Chinese characteristics under the global perspective.展开更多
Estimation of S-wave velocity using logging data has mainly been performed for sandstone, mudstone and oil and gas strata, while its application to hydrate reservoirs has been largely overlooked. In this paper we pres...Estimation of S-wave velocity using logging data has mainly been performed for sandstone, mudstone and oil and gas strata, while its application to hydrate reservoirs has been largely overlooked. In this paper we present petxophysical methods to estimate the S-wave velocity of hydrate reservoirs with the P-wave velocity and the density as constraints. The three models used in this paper are an equivalent model (MBGL), a three-phase model (TPBE), and a thermo-elasticity model (TEM). The MBGL model can effectively describe the internal relationship among the components of the rock, and the estimated P-wave velocities are in good agreement with the measured data (2.8% error). However, in the TPBE model, the solid, liquid and gas phases axe considered to be independent of each other, and the estimation results are relatively low (46.6% error). The TEM model is based on the sensitivity of the gas hydrate to temperature and pressure, and the accuracy of the estimation results is also high (3.6% error). Before the estimation, the occurrence patterns of hydrates in the Shenhu area were examined, and occurrence state one (the hydrate is in solid form in the reservoir) was selected for analysis. By using the known P-wave velocity and density as constraints, a reasonable S-wave velocity value (ranging from 400 to 1100 m s 1 and for a hydrate layer of 1100 m s 1) can be obtained through multiple iterations. These methods and results provide new data and technical support for further research on hydrates and other geological features in the Shenhu area.展开更多
Cave carbonate formations are characterized by heterogeneity, which makes electrical log prediction difficult. It is currently important to know how to use the dual laterolog to accurately identify and quantitatively ...Cave carbonate formations are characterized by heterogeneity, which makes electrical log prediction difficult. It is currently important to know how to use the dual laterolog to accurately identify and quantitatively evaluate caves. Using numerical simulation to calculate electrical log responses can provide a theoretical basis for cave identification and evaluation. In this paper, based on the dual laterolog principles, we first study different size spherical cave models using the finite element method (FEM), determine a relation between resistivity and cave filling after comprehensively studying the log responses of cave models with different filling material, and finally study the dual laterolog responses on caves filled with shale, limestone, conglomerate, and thin laminated formation of sand and shale. The numerical results provide a theoretical basis for identification and evaluation of carbonate cave reservoirs.展开更多
Shale gas is a practical resource with great potential that could be economically explored and developed in the near future. It has been commercially developed in North America and other places. Featuring a vast distr...Shale gas is a practical resource with great potential that could be economically explored and developed in the near future. It has been commercially developed in North America and other places. Featuring a vast distribution, a low abundance,unfavorable reservoir conditions, ultra-low permeability and a fast production decline, shale gas is more difficult to develop than conventional natural gas, as it needs advanced drilling and completion technology to develop. During the early stage of shale gas exploration and development, the United States offered enterprises necessary incentives such as tax reductions and exemptions and subsidies to achieve sustainable shale gas development and encourage technological progresses. By comparing the state of China's shale gas development with that of the US' in terms of geological conditions, production technology,market price, tax relief, subsidy periods and amount, this paper intends to put forward related suggestions for the effective development of shale gas according to the current status of development.展开更多
The construction of waste rock dumps on existing tailing ponds has been put into practice in China to save precious land resources. This work focuses on the safety assessment of the Daheishan molybdenum mine waste roc...The construction of waste rock dumps on existing tailing ponds has been put into practice in China to save precious land resources. This work focuses on the safety assessment of the Daheishan molybdenum mine waste rock dump under construction on two adjoining tailings ponds. The consolidation of the tailings foundation and the filling quality of the waste rock are investigated by the transient electromagnetic method through detecting water-rich areas and loose packing areas, from which, the depth of phreatic line is also estimated. With such information and the material parameters, the numerical method based on shear strength reduction is applied to analyzing the overall stability of the waste rock dump and the tailings ponds over a number of typical cross sections under both current and designed conditions, where the complex geological profiles exposed by site investigation are considered. Through numerical experiments, the influence of soft lenses in the tailings and possible loose packing areas in the waste rock is examined. Although large displacements may develop due to the soft tailings foundation, the results show that the waste rock dump satisfies the safety requirements under both present and designed conditions.展开更多
Extreme weather and climate events are likely to cause disastrous consequences for agriculture and food security. This study investigated the impacts of drought in year 2012 on corn yield in the United States Corn Bel...Extreme weather and climate events are likely to cause disastrous consequences for agriculture and food security. This study investigated the impacts of drought in year 2012 on corn yield in the United States Corn Belt by integrating county-level crop yield data from the USDA NASS Quick Stats database and precipitation data from the NCDC GHCN-Daily database. It is found that precipitation over an 8-week period in corn growth stages is critical for corn yield, the logarithm of precipitation during the period explained 55% of corn yield variation. The results indicated the importance of water supply in corn silking stage, and provided an approach to assess the impacts of drought on corn yield quantitatively.展开更多
Reservoir-landslide is mainly caused by changes in hydrodynamic conditions of slope interior at the time of water storage or discharge. The current study mainly focuses on the typical reservoirlandslide, but the sudde...Reservoir-landslide is mainly caused by changes in hydrodynamic conditions of slope interior at the time of water storage or discharge. The current study mainly focuses on the typical reservoirlandslide, but the sudden occurrence of some unknown landslides brought a lot of difficulties for hazards prevention. Therefore, we proposed a method to evaluate the regional scale reservoir-landslide hazard. We took Wanzhou section of Three Gorges Reservoir(China) as the study area and systemically and synthetically carried out the reservoir-landslide hazard evaluation under the condition of water level regulation. Firstly, we made reservoir-landslide susceptibility assessment by using the methods of spatial analysis and statistics based on geological and geomorphological materials and field survey data, and then, analyzed the regional-scale slope stability based on the infinite slope model used to analyze the bank slope stability change under the condition of water fluctuation, finally, developed a reservoir-landslide hazard evaluation model based on the results of susceptibility and stability. The hazard evaluation model was used to predict and evaluate the hazard change under the role of water level regulation. The results showed that the landslide hazard of the whole region decreased during water storage, landslide hazards increased during water discharge. The faster the regulation speed, the greater the slope hazard. The results can provide the basis for hazard management and regional land-use planning.展开更多
A library of 2 ×107 random octapeptides was constructed by use of phagemid-based monovalent phage display system. The randomly synthesized degenerated oligodeoxyribonucleotides (oligos ) were fused to the truncat...A library of 2 ×107 random octapeptides was constructed by use of phagemid-based monovalent phage display system. The randomly synthesized degenerated oligodeoxyribonucleotides (oligos ) were fused to the truncated g Ⅲ (p230-p403). Sequence analysis of 11 randomly chosen clones suggested that the degenerated inserts and its deduced amino acid (aa) sequences are randomly distributed. The library was used to select binding peptides to the monoclonal antibody (mAb) 9E10, which recognizes a continuous decapeptide epi- tope of denatured human c-myc protein. After four to five rounds of panning, most of the eluted clones could bind to 9E10. Sequence analysis of the selected positive clones indicated that the binding sequences could fall into two classes, one class (clone 1) shares a consensus motif, ISE x x L, with c-myc decapeptide; and the sequences of the other class are entirely different. The binding of both classes to 9E10 could be specifically inhibited by free c-myc decapeptide. The immunogenicity of the phage peptide was further investigated by construction of multivalent displayed phage peptides and immunization of animals with or without adjuvant. ELISA and competitive ELISA showed that anti-serum from both mice and rabbit immunized with either clone could bind to the original antigen, c-myc decapeptide. These results denote that in spite of the dissimilarity of the selected peptides with c-myc decapeptide, they are capable of inducing similar immune respones in vivo, thus actually mimicking the antigen epitope.展开更多
Malampuzha reservoir is a multipurpose reservoir in south India. Seven water samples and four sediment samples were studied for the physico-chemical and bacteriological nature of the Malampuzha reservoir water and sed...Malampuzha reservoir is a multipurpose reservoir in south India. Seven water samples and four sediment samples were studied for the physico-chemical and bacteriological nature of the Malampuzha reservoir water and sediments. Bacteriological analysis indicated the microbial contamination of the reservoir and the physico-chemical characteristics indicated that the water is non potable directly. Analysis of irrigational water quality by SAR, Kelly's ratio and SSP indicates that the reservoir water is suitable for irrigation. Heavy metal pollution of the sediments was evaluated based on Sediment Quality Guidelines (SQG), Pollution Load Index (PLI) and degree of contamination (Cd) of soil in four stations. Principal Component Analysis (PCA) was done to find out the possible linear combination of the original variables of trace metals. Results of PCA showed that no collinearity existed among the studied metals. However, emphasis on the monitoring of Cu and Ni should be preferred because of its alarmingly higher contamination value.展开更多
The small hydropower(SHP) will be less competitive in the absence of environmental value.The lack of information has become an important obstacle challenging decision-makers in resource-use choices.This paper is an ap...The small hydropower(SHP) will be less competitive in the absence of environmental value.The lack of information has become an important obstacle challenging decision-makers in resource-use choices.This paper is an application of contingent valuation method(CVM) in rural China to estimate the willingness-to-pay(WTP) for environmental services provided by exiting hydropower station.Using the single-bounded and dichotomouschoice CVM,the ecological value of Tongjiqiao Reservoir(TJQR) is estimated,and the annual mean WTPs of single-bounded and double-bounded CVM estimation are 141.05 and 219.52 Yuan(RMB)/a,respectively.The 95% confidence interval of annual WTP on an average is 118.47,166.79 Yuan(RMB)/a and 204.41,236.22(Yuan RMB)/a,respectively.In contrast,double-bounded model could obtain much more information of WTP of the investigated,thus reducing the confidence interval of estimation,and enhancing the estimation accuracy of the WTP.According to the estimated mean WTP of the double-bounded CVM,the total ecosystem service value of the TJQR is 15.54 million Yuan(RMB).Compared with the conventional electricity of fossil power and large hydropower,the SHP will be less competitive in the absence of non-market value,ignoring that the environmental impacts of existing SHP will undermine the healthy development of clean energy sector.展开更多
A study about some physicochemical parameters of Egbe reservoir was carried out from September 2005 to December 2006. The parameters include mean temperature, pH, conductivity, alkalinity, TSS, TDS, DO and BOD which h...A study about some physicochemical parameters of Egbe reservoir was carried out from September 2005 to December 2006. The parameters include mean temperature, pH, conductivity, alkalinity, TSS, TDS, DO and BOD which have values of 28.7±0.9 ℃ ; 8.3±0.3; 831±172.5 μS/cm; 165.4±18.3 mg/L; 0.06±0.1 mg/L; 0.4±0.6 mg/L; 7.8±2.4 mg/L and 5.2±1.6mg/L, respectively. Temperature and pH were measured in the field using mercury-in-glass thermometer calibrated in degrees Celsius and pH meter, respectively. TSS and TDS were measured by grayimetric methods, while alkalinity was measured titrimetrically and DO and BOD were measured by Winkler's method. For the nutrients, nitrate was measured color±metrically, phosphate by Stannous Chloride method and sulphate by turbidimetric method. Mean concentration of nitrate, phosphate, and sulphate were 15.6±8.6 rag/L; 42.5±19.4 mg/L and 72.3±14.7 mg/L respectively. Nowadays, eutrophication of natural waters is one of the most significant causes of deterioration of water quality, and nitrates and phosphates are probably the key nutrients in controlling the growth of aquatic plants. Though the mean concentration of nitrates and phosphates in the reservoir water were within the acceptable limit, yet their concentrations in some locations of reservoir were high enough to encourage the growth of aquatic macrophytes which would increase productivities. Hence, it is necessary to check their further increase, and periodic monitoring and preventive measures must be adopted to save the reservoir from eutrophication.展开更多
There has not been life cycle assessment (LCA) software applicable to China's products. To faciliate the development of LCA software system in China, we built an object-oriented LCA software system plantform based...There has not been life cycle assessment (LCA) software applicable to China's products. To faciliate the development of LCA software system in China, we built an object-oriented LCA software system plantform based on LCA international standards ISO 14040 to ISO 14043 and the commonness of diverse products. The system includes six modules: disassembly module, data collection module, arithmetic module, drawing module, database module and control module. It evaluates all economic and environmental impacts during the whole life cycle of a product. The integrated life cycle inventory database system allows dynamic expansion, which makes the effort required for data collection reduce with the increase of the system's application. With the improvement of human environmental-awareness, the demand of environment-friendly products is increasing, and ecological design of products has become a critical part in products development. Consummation of the LCA software system will provide a powerful tool for designing and developing Chinese ecological products.展开更多
The objective of the study was to establish spatial land evaluation for oil palm cultivation using GIS (geographic information system). The study area is situated in the KESEDAR region in the state of Kelantan, Mala...The objective of the study was to establish spatial land evaluation for oil palm cultivation using GIS (geographic information system). The study area is situated in the KESEDAR region in the state of Kelantan, Malaysia. The evaluation of the land in terms of the suitability classes were based on the method of FAO (Food and Agriculture Oganization of the United Nations). Five land qualities are important for determining the physical land suitability for oil palm; these are nutrient availability, oxygen availability, water availability, workability and availability of foothold for roots. Each of the above mentioned land qualities with associated attribute data were digitally encoded in a GIS database to create thermatic layers. Overlay operation on the layer produced resultant polygonal layer each of which is a land unit with characteristics of the land. The results from GIS overlay analyses showed that Bungor, Chat, Chempaka, Alluvium, Musang and Tok Yong series are highly suitable while Kawang series is moderately suitable for oil palm cultivation. The same results were obtained by using parametric-limitation method.展开更多
Land use alternatives are sought to boost agricultural income and productivity in Hainan Island, China.Regional differences exist in crop limitations, such as typhoon risk, low temperatures, poor soil fertility, and d...Land use alternatives are sought to boost agricultural income and productivity in Hainan Island, China.Regional differences exist in crop limitations, such as typhoon risk, low temperatures, poor soil fertility, and drought. In this study a crop zonation was made for a range of crops, among which is banana, as a way to: 1)establish areas for potential expansion for banana, and 2) identify limitations and options for crop and land management. A spatial soil and terrain database of Hainan Island (1:250 000) was linked to the automated land evaluation system (ALES). The qualitative models were verified by comparing suitability maps with actual land use. The results may support policy formulation on issues such as alternatives to current land use, assessment of best management practices, and the need for fertilizer programmes.展开更多
Image enhancement is a popular technique,which is widely used to improve the visual quality of images.While image enhancement has been extensively investigated,the relevant quality assessment of enhanced images remain...Image enhancement is a popular technique,which is widely used to improve the visual quality of images.While image enhancement has been extensively investigated,the relevant quality assessment of enhanced images remains an open problem,which may hinder further development of enhancement techniques.In this paper,a no-reference quality metric for digitally enhanced images is proposed.Three kinds of features are extracted for characterizing the quality of enhanced images,including non-structural information,sharpness and naturalness.Specifically,a total of 42 perceptual features are extracted and used to train a support vector regression(SVR) model.Finally,the trained SVR model is used for predicting the quality of enhanced images.The performance of the proposed method is evaluated on several enhancement-related databases,including a new enhanced image database built by the authors.The experimental results demonstrate the efficiency and advantage of the proposed metric.展开更多
The 21 st century is an era of knowledge-based economy. With more high-quality talents, the technical schools can achieve sustainable development, making contributions due to the field of vocational education. Under t...The 21 st century is an era of knowledge-based economy. With more high-quality talents, the technical schools can achieve sustainable development, making contributions due to the field of vocational education. Under this background, how to develop and manage human resources has become an important topic in the management of technical schools in our country. Management believes that there are many ways to develop and manage human resources, and the key problem is to find specific ways to solve problems. It is a feasible strategy to stimulate the enthusiasm of human resources through performance appraisal.展开更多
基金Supported by Tianjin Aquatic Species Diveristy Surveying,Monitoring and Evaluation Proejct~~
文摘[Objective] The aim was to research macrobenthos community structure and its relations with environmental factors in three reservoirs. [Method] Benthic diversity and water quality of Yuqiao Reservoir, Beidagang Reservoir and Er- wangzhuang Reservoir were investigated in May, July and September 2011, respec- tively. []Result] Of all the 14 sampling sites, 22 species of macroinvertebrates were collected, totally, which included 6 species of aquatic insects, 7 species of Mollusca, 2 species of Crustacean, 7 species of Oligochaeta. The species of macroinverte- brates during May, July and September in Yuqiao reservoir were 11, 8 and 10, respectively. The dominant species were Chironomus sinicus, and Monopylephorus limosus. The average density and biomass of the macrobenthos were 132.43 ind./m2 and 50.09 g/m2. Yuqiao reservoir was mostly at status of premediate polluted, according to the Margalef index, Shannon index and Pielou index. The species of during May, July and September in Beidagang reservoir were 5 5 and 5, respectively. The dominant species were Chironomus sinicus, Penaeus vannamei. The average density and biomass of the macrobenthos were 218 ind./m2 and 2.70 g/m2. Beidagang reservoir was mostly at status of heavy polluted, accord- ing to the Margalef index, Shannon-wiener index, Pielou index. The species of during May, July and September in Erwangzhuang reservoir were 3, 5 and 5, respectively. The dominant species were Monopylephorus limosus, Chi- ronomus sinicus. The average density and biomass of the macrobenthos were 104 ind/m2 and 0.20 g/m2. Erwangzhuang reservoir was mostly at status of intermediate polluted, according to the Margalef index, Shannon index, Pielou index. The density of zoobenthos in Yuqiao Reservoir was positively significantly correlated with TP (P〉 0.05), negatively correlated with NH4+-N (P〉0.05), positively correlated with COD (P〈 0.01), not significantly correlated with other environment factors (P〉0.05). There was no significant correlation between biomass of zoobenthos and environment factors. The density of zoobenthos in Beidagang Reservoir with NH4+-N was positively signif- icantly correlated (P〈0.05), not significantly correlated with other aquatic environment factors (P〉0.05). There was no significant correlation between biomass of zoobenthos and environment factors. The density of zoobenthos in Erwangzhuang Reser- voir with NO3-N was positively significantly correlated (P〈0.05), not significant cor- related with other aquatic environment factors (F〉0.05). The biomass of zoobenthos in Erwangzhuang Reservoir with NH4+-N was positively significantly correlated (P〈 0.05), not significant correlated with other aquatic environment factors (P〉0.05). [Conclusion] It is indicated that this three reservoirs were all eutrophied and polluted, and the eurephication extent change of water in three reservoirs is as follows: Beidagang reservoir〉Erwangzhuang reservoir〉Yuqiao reservoir.
基金The National Key Technology R&D Program of China during the11th Five-Year Plan Period(No.2006BAH02A06).
文摘The collector managed inventory(CMI)management idea is introduced based on the comparison of manufacturer and third-party logistics(3PL)implementing vendor managed inventory(VMI)services.Considering recovery costs,the service pricing strategies for 3PL corporations implementing VMI are studied to meet two conditions of participation constraints and incentive-compatibility constraints.The numerical simulation results indicate that the supply chain partners' profits change after considering recovery costs,and the 3PL corporation's profits and the total profits increase first,and then decrease.The retailers' and manufacturers' profits also increase.The total profits of the supply chain have a characteristic of increasing first and then decreasing with the increase of the callback ratio of unsold products.The concrete extremum point is codetermined by price flexibility,service pricing of the 3PL corporation,callback price and callback ratio.
文摘This paper has 4 parts. Part 1 presents a comparative analysis of think tank evaluation methods. Part 2 introduces the AMI index system for comprehensive evaluation of global think tanks. Part 3 describes the current situation of global think tanks based on ranking by AMI. Part 4 proposes the construction of new type think tanks with Chinese characteristics under the global perspective.
基金supported by the National Natural Science Foundation of China(Nos.41304096 and 41176077)the National Science and Technology Major Project of China(No.2016ZX05024-001-002)+2 种基金the National High-tech R&D Program of China(863 ProgramNo.2013AA0925 01)the Fundamental Research Funds for the Central Universities(No.201762019)
文摘Estimation of S-wave velocity using logging data has mainly been performed for sandstone, mudstone and oil and gas strata, while its application to hydrate reservoirs has been largely overlooked. In this paper we present petxophysical methods to estimate the S-wave velocity of hydrate reservoirs with the P-wave velocity and the density as constraints. The three models used in this paper are an equivalent model (MBGL), a three-phase model (TPBE), and a thermo-elasticity model (TEM). The MBGL model can effectively describe the internal relationship among the components of the rock, and the estimated P-wave velocities are in good agreement with the measured data (2.8% error). However, in the TPBE model, the solid, liquid and gas phases axe considered to be independent of each other, and the estimation results are relatively low (46.6% error). The TEM model is based on the sensitivity of the gas hydrate to temperature and pressure, and the accuracy of the estimation results is also high (3.6% error). Before the estimation, the occurrence patterns of hydrates in the Shenhu area were examined, and occurrence state one (the hydrate is in solid form in the reservoir) was selected for analysis. By using the known P-wave velocity and density as constraints, a reasonable S-wave velocity value (ranging from 400 to 1100 m s 1 and for a hydrate layer of 1100 m s 1) can be obtained through multiple iterations. These methods and results provide new data and technical support for further research on hydrates and other geological features in the Shenhu area.
基金supported by State Key Laboratory of Petroleum Resources and Prospecting (Grant No. 2009009)Basic Scientific Research Special Fund of Central Colleges (Grant No. 2010ZY28)National Major Projects (Grant No.2008ZX05023-005 and 2008ZX05035-002)
文摘Cave carbonate formations are characterized by heterogeneity, which makes electrical log prediction difficult. It is currently important to know how to use the dual laterolog to accurately identify and quantitatively evaluate caves. Using numerical simulation to calculate electrical log responses can provide a theoretical basis for cave identification and evaluation. In this paper, based on the dual laterolog principles, we first study different size spherical cave models using the finite element method (FEM), determine a relation between resistivity and cave filling after comprehensively studying the log responses of cave models with different filling material, and finally study the dual laterolog responses on caves filled with shale, limestone, conglomerate, and thin laminated formation of sand and shale. The numerical results provide a theoretical basis for identification and evaluation of carbonate cave reservoirs.
文摘Shale gas is a practical resource with great potential that could be economically explored and developed in the near future. It has been commercially developed in North America and other places. Featuring a vast distribution, a low abundance,unfavorable reservoir conditions, ultra-low permeability and a fast production decline, shale gas is more difficult to develop than conventional natural gas, as it needs advanced drilling and completion technology to develop. During the early stage of shale gas exploration and development, the United States offered enterprises necessary incentives such as tax reductions and exemptions and subsidies to achieve sustainable shale gas development and encourage technological progresses. By comparing the state of China's shale gas development with that of the US' in terms of geological conditions, production technology,market price, tax relief, subsidy periods and amount, this paper intends to put forward related suggestions for the effective development of shale gas according to the current status of development.
基金Projects(51209118,71373245)supported by the National Natural Science Foundation of ChinaProject(2014JBKY01)supported by the Fundamental Research Funds for CASST,China
文摘The construction of waste rock dumps on existing tailing ponds has been put into practice in China to save precious land resources. This work focuses on the safety assessment of the Daheishan molybdenum mine waste rock dump under construction on two adjoining tailings ponds. The consolidation of the tailings foundation and the filling quality of the waste rock are investigated by the transient electromagnetic method through detecting water-rich areas and loose packing areas, from which, the depth of phreatic line is also estimated. With such information and the material parameters, the numerical method based on shear strength reduction is applied to analyzing the overall stability of the waste rock dump and the tailings ponds over a number of typical cross sections under both current and designed conditions, where the complex geological profiles exposed by site investigation are considered. Through numerical experiments, the influence of soft lenses in the tailings and possible loose packing areas in the waste rock is examined. Although large displacements may develop due to the soft tailings foundation, the results show that the waste rock dump satisfies the safety requirements under both present and designed conditions.
文摘Extreme weather and climate events are likely to cause disastrous consequences for agriculture and food security. This study investigated the impacts of drought in year 2012 on corn yield in the United States Corn Belt by integrating county-level crop yield data from the USDA NASS Quick Stats database and precipitation data from the NCDC GHCN-Daily database. It is found that precipitation over an 8-week period in corn growth stages is critical for corn yield, the logarithm of precipitation during the period explained 55% of corn yield variation. The results indicated the importance of water supply in corn silking stage, and provided an approach to assess the impacts of drought on corn yield quantitatively.
基金supported by the International Cooperation Program of the Ministry of Science and Technology of China (Grant No. 2013DFA21720)the National Science & Technology Support Program during the Twelfth Five-Year Plan Period (Grant No. 2011BAK12B01)
文摘Reservoir-landslide is mainly caused by changes in hydrodynamic conditions of slope interior at the time of water storage or discharge. The current study mainly focuses on the typical reservoirlandslide, but the sudden occurrence of some unknown landslides brought a lot of difficulties for hazards prevention. Therefore, we proposed a method to evaluate the regional scale reservoir-landslide hazard. We took Wanzhou section of Three Gorges Reservoir(China) as the study area and systemically and synthetically carried out the reservoir-landslide hazard evaluation under the condition of water level regulation. Firstly, we made reservoir-landslide susceptibility assessment by using the methods of spatial analysis and statistics based on geological and geomorphological materials and field survey data, and then, analyzed the regional-scale slope stability based on the infinite slope model used to analyze the bank slope stability change under the condition of water fluctuation, finally, developed a reservoir-landslide hazard evaluation model based on the results of susceptibility and stability. The hazard evaluation model was used to predict and evaluate the hazard change under the role of water level regulation. The results showed that the landslide hazard of the whole region decreased during water storage, landslide hazards increased during water discharge. The faster the regulation speed, the greater the slope hazard. The results can provide the basis for hazard management and regional land-use planning.
文摘A library of 2 ×107 random octapeptides was constructed by use of phagemid-based monovalent phage display system. The randomly synthesized degenerated oligodeoxyribonucleotides (oligos ) were fused to the truncated g Ⅲ (p230-p403). Sequence analysis of 11 randomly chosen clones suggested that the degenerated inserts and its deduced amino acid (aa) sequences are randomly distributed. The library was used to select binding peptides to the monoclonal antibody (mAb) 9E10, which recognizes a continuous decapeptide epi- tope of denatured human c-myc protein. After four to five rounds of panning, most of the eluted clones could bind to 9E10. Sequence analysis of the selected positive clones indicated that the binding sequences could fall into two classes, one class (clone 1) shares a consensus motif, ISE x x L, with c-myc decapeptide; and the sequences of the other class are entirely different. The binding of both classes to 9E10 could be specifically inhibited by free c-myc decapeptide. The immunogenicity of the phage peptide was further investigated by construction of multivalent displayed phage peptides and immunization of animals with or without adjuvant. ELISA and competitive ELISA showed that anti-serum from both mice and rabbit immunized with either clone could bind to the original antigen, c-myc decapeptide. These results denote that in spite of the dissimilarity of the selected peptides with c-myc decapeptide, they are capable of inducing similar immune respones in vivo, thus actually mimicking the antigen epitope.
文摘Malampuzha reservoir is a multipurpose reservoir in south India. Seven water samples and four sediment samples were studied for the physico-chemical and bacteriological nature of the Malampuzha reservoir water and sediments. Bacteriological analysis indicated the microbial contamination of the reservoir and the physico-chemical characteristics indicated that the water is non potable directly. Analysis of irrigational water quality by SAR, Kelly's ratio and SSP indicates that the reservoir water is suitable for irrigation. Heavy metal pollution of the sediments was evaluated based on Sediment Quality Guidelines (SQG), Pollution Load Index (PLI) and degree of contamination (Cd) of soil in four stations. Principal Component Analysis (PCA) was done to find out the possible linear combination of the original variables of trace metals. Results of PCA showed that no collinearity existed among the studied metals. However, emphasis on the monitoring of Cu and Ni should be preferred because of its alarmingly higher contamination value.
基金supported by National Natural Science Foundation of China in 2008 (Grant No. 70873108)Zhejiang Provincial Natural Scien8ce Foundation of China (Grant No. Z607126)+1 种基金the key research project funded by a national key research base for humanities and social sciences under the guidance of the Ministry of Education (Grant No. 2007JJD630014)Programfor New Century Excellent Talents in University in 2008
文摘The small hydropower(SHP) will be less competitive in the absence of environmental value.The lack of information has become an important obstacle challenging decision-makers in resource-use choices.This paper is an application of contingent valuation method(CVM) in rural China to estimate the willingness-to-pay(WTP) for environmental services provided by exiting hydropower station.Using the single-bounded and dichotomouschoice CVM,the ecological value of Tongjiqiao Reservoir(TJQR) is estimated,and the annual mean WTPs of single-bounded and double-bounded CVM estimation are 141.05 and 219.52 Yuan(RMB)/a,respectively.The 95% confidence interval of annual WTP on an average is 118.47,166.79 Yuan(RMB)/a and 204.41,236.22(Yuan RMB)/a,respectively.In contrast,double-bounded model could obtain much more information of WTP of the investigated,thus reducing the confidence interval of estimation,and enhancing the estimation accuracy of the WTP.According to the estimated mean WTP of the double-bounded CVM,the total ecosystem service value of the TJQR is 15.54 million Yuan(RMB).Compared with the conventional electricity of fossil power and large hydropower,the SHP will be less competitive in the absence of non-market value,ignoring that the environmental impacts of existing SHP will undermine the healthy development of clean energy sector.
文摘A study about some physicochemical parameters of Egbe reservoir was carried out from September 2005 to December 2006. The parameters include mean temperature, pH, conductivity, alkalinity, TSS, TDS, DO and BOD which have values of 28.7±0.9 ℃ ; 8.3±0.3; 831±172.5 μS/cm; 165.4±18.3 mg/L; 0.06±0.1 mg/L; 0.4±0.6 mg/L; 7.8±2.4 mg/L and 5.2±1.6mg/L, respectively. Temperature and pH were measured in the field using mercury-in-glass thermometer calibrated in degrees Celsius and pH meter, respectively. TSS and TDS were measured by grayimetric methods, while alkalinity was measured titrimetrically and DO and BOD were measured by Winkler's method. For the nutrients, nitrate was measured color±metrically, phosphate by Stannous Chloride method and sulphate by turbidimetric method. Mean concentration of nitrate, phosphate, and sulphate were 15.6±8.6 rag/L; 42.5±19.4 mg/L and 72.3±14.7 mg/L respectively. Nowadays, eutrophication of natural waters is one of the most significant causes of deterioration of water quality, and nitrates and phosphates are probably the key nutrients in controlling the growth of aquatic plants. Though the mean concentration of nitrates and phosphates in the reservoir water were within the acceptable limit, yet their concentrations in some locations of reservoir were high enough to encourage the growth of aquatic macrophytes which would increase productivities. Hence, it is necessary to check their further increase, and periodic monitoring and preventive measures must be adopted to save the reservoir from eutrophication.
文摘There has not been life cycle assessment (LCA) software applicable to China's products. To faciliate the development of LCA software system in China, we built an object-oriented LCA software system plantform based on LCA international standards ISO 14040 to ISO 14043 and the commonness of diverse products. The system includes six modules: disassembly module, data collection module, arithmetic module, drawing module, database module and control module. It evaluates all economic and environmental impacts during the whole life cycle of a product. The integrated life cycle inventory database system allows dynamic expansion, which makes the effort required for data collection reduce with the increase of the system's application. With the improvement of human environmental-awareness, the demand of environment-friendly products is increasing, and ecological design of products has become a critical part in products development. Consummation of the LCA software system will provide a powerful tool for designing and developing Chinese ecological products.
文摘The objective of the study was to establish spatial land evaluation for oil palm cultivation using GIS (geographic information system). The study area is situated in the KESEDAR region in the state of Kelantan, Malaysia. The evaluation of the land in terms of the suitability classes were based on the method of FAO (Food and Agriculture Oganization of the United Nations). Five land qualities are important for determining the physical land suitability for oil palm; these are nutrient availability, oxygen availability, water availability, workability and availability of foothold for roots. Each of the above mentioned land qualities with associated attribute data were digitally encoded in a GIS database to create thermatic layers. Overlay operation on the layer produced resultant polygonal layer each of which is a land unit with characteristics of the land. The results from GIS overlay analyses showed that Bungor, Chat, Chempaka, Alluvium, Musang and Tok Yong series are highly suitable while Kawang series is moderately suitable for oil palm cultivation. The same results were obtained by using parametric-limitation method.
基金Project supported by United Nation Development Programme (UNDP, No. CPR/96/105/A99).
文摘Land use alternatives are sought to boost agricultural income and productivity in Hainan Island, China.Regional differences exist in crop limitations, such as typhoon risk, low temperatures, poor soil fertility, and drought. In this study a crop zonation was made for a range of crops, among which is banana, as a way to: 1)establish areas for potential expansion for banana, and 2) identify limitations and options for crop and land management. A spatial soil and terrain database of Hainan Island (1:250 000) was linked to the automated land evaluation system (ALES). The qualitative models were verified by comparing suitability maps with actual land use. The results may support policy formulation on issues such as alternatives to current land use, assessment of best management practices, and the need for fertilizer programmes.
基金supported in part by the National Natural Science Foundation of China under Grant 61379143in part by the Fundamental Research Funds for the Central Universities under Grant 2015QNA66in part by the Qing Lan Project of Jiangsu Province
文摘Image enhancement is a popular technique,which is widely used to improve the visual quality of images.While image enhancement has been extensively investigated,the relevant quality assessment of enhanced images remains an open problem,which may hinder further development of enhancement techniques.In this paper,a no-reference quality metric for digitally enhanced images is proposed.Three kinds of features are extracted for characterizing the quality of enhanced images,including non-structural information,sharpness and naturalness.Specifically,a total of 42 perceptual features are extracted and used to train a support vector regression(SVR) model.Finally,the trained SVR model is used for predicting the quality of enhanced images.The performance of the proposed method is evaluated on several enhancement-related databases,including a new enhanced image database built by the authors.The experimental results demonstrate the efficiency and advantage of the proposed metric.
文摘The 21 st century is an era of knowledge-based economy. With more high-quality talents, the technical schools can achieve sustainable development, making contributions due to the field of vocational education. Under this background, how to develop and manage human resources has become an important topic in the management of technical schools in our country. Management believes that there are many ways to develop and manage human resources, and the key problem is to find specific ways to solve problems. It is a feasible strategy to stimulate the enthusiasm of human resources through performance appraisal.