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Resistant Evaluation of Kiwifruit Rootstocks to Root Zone Hypoxia Stress 被引量:7
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作者 Yinfa Mi Xiaowei Ma Shuangchen Chen 《American Journal of Plant Sciences》 2013年第4期945-954,共10页
In this thesis, 10 species of kiwifruit rootstocks were treated with hydroponics hypoxia to study their root zone hypoxia tolerance. The results were as follows: growth of all kiwifruit seedlings was inhibited. The ma... In this thesis, 10 species of kiwifruit rootstocks were treated with hydroponics hypoxia to study their root zone hypoxia tolerance. The results were as follows: growth of all kiwifruit seedlings was inhibited. The max length of new root, plant height, plant biomass, root activity, relative growth rate of leaves, and content of chlorophyll in leaves under root zone hypoxia stress obviously declined comparing with control. MDA content, relative conductance in the leaves and roots all increased in 10 kinds of kiwifruit seedlings. The sensitivities of 10 kinds’ kiwifruit seedlings to hypoxia stress were obviously different. With the method of subordinate function and cluster analysis, the adversity resistance coefficient of 10 kinds’ kiwifruit seedlings, were comprehensively evaluated in order to appraise their hypoxia-tolerance abilities. According to the results, “Hayward”, “Qinmei”, “Jinxiang”, “Kuoye”, “Huayou” kiwifruit seedlings held higher tolerance to root zone hypoxia stress, while “Hongyang” kiwifruit seedlings were sensitive to root zone hypoxia stress. The others, including “Xixuan”, “Maohua”, “Jinhua”, “Shanli” kiwifruit seedlings kept moderate resistant intensity to root zone hypoxia stress. The kiwifruit seedlings’ resistance order from strong to weak was: “Hayward” > “Qinmei” > “Jinxiang” > “Kuoye” > “Huayou” > “Xixuan” > “Maohua” > “Jinhua” > “Shanli” > “Hongyang”. 展开更多
关键词 KIWIFRUIT ROOTSTOCK Root zone HYPOXIA Stress RESISTANT evaluation
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Identification and Evaluation of Low Resistivity Pay Zones by Well Logs and the Petrophysical Research in China 被引量:3
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作者 Mao Zhiqiang Kuang Lichun +3 位作者 Xiao Chengwen Li Guoxin Zhou Cancan Ouyang Jian 《Petroleum Science》 SCIE CAS CSCD 2007年第1期41-48,共8页
This paper presents an overview of petrophysical research and exploration achievements of low resistivity pay (LRP) zone by well logs in China. It includes geological characteristics and characteristics of well log ... This paper presents an overview of petrophysical research and exploration achievements of low resistivity pay (LRP) zone by well logs in China. It includes geological characteristics and characteristics of well log response of the low resistivity pay zones discovered and evaluated in recent years, as well as the problems in recognizing and evaluating low resistivity pay zones by well logs. The research areas mainly include the Neogene formations in the Bohai Bay Basin, the Triassic formations in the northern Tarim Basin and the Cretaceous formations in the Junggar Basin, The petrophysical research concerning recognition and evaluation of the low resistivity pays, based on their genetic types, is introduced in this paper. 展开更多
关键词 Low-resistivity pay zone in China origin and type petrophysical research identification and evaluation by well logs
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Zoning Evaluation of Hourly Precipitation in High-resolution Regional Numerical Models over Hainan Island
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作者 冯箫 吴俞 +1 位作者 杨薇 李勋 《Journal of Tropical Meteorology》 SCIE 2023年第4期460-472,共13页
This study assesses the performance of three high-resolution regional numerical models in predicting hourly rainfall over Hainan Island from April to October for the years from 2020 to 2022.The rainfall amount,frequen... This study assesses the performance of three high-resolution regional numerical models in predicting hourly rainfall over Hainan Island from April to October for the years from 2020 to 2022.The rainfall amount,frequency,intensity,duration,and diurnal cycle are examined through zoning evaluation.The results show that the China Meteor-ological Administration Guangdong Rapid Update Assimilation Numerical Forecast System(CMA-GD)tends to forecast a higher occurrence of light precipitation.It underestimates the late afternoon precipitation and the occurrence of short-duration events.The China Meteorological Administration Shanghai Numerical Forecast Model System(CMA-SH9)reproduces excessive precipitation at a higher frequency and intensity throughout the island.It overestimates rainfall during the late afternoon and midnight periods.The simulated most frequent peak times of rainfall in CMA-SH9 are 0-1 hour deviations from the observed data.The China Meteorological Administration Mesoscale Weather Numerical Forecasting System(CMA-MESO)displays a similar pattern to rainfall observations but fails to replicate reasonable structure and diurnal variation of frequency-intensity.It underestimates the occurrence of long-duration events and overestimates related rainfall amounts from midnight to early morning.Notably,significant discrepancies are observed in the predictions of the three models for areas with complex terrain,such as the central,southeastern,and southwestern regions of Hainan Island. 展开更多
关键词 Hainan Island hourly precipitation regional numerical model zoning evaluation
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Identification of watered-out zones in carbonate reservoirs using resistivity curve reconstruction based on reservoir classification
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作者 Fei Wang Lun Zhao +2 位作者 Huiyuan Bian Chengqian Tan Jianxin Li 《Energy Geoscience》 2023年第2期128-134,共7页
The KT-II layer in the Zananor Oilfield,Caspian Basin,Kazakhstan,contains carbonate reservoirs of various types.The complex pore structure of the reservoirs have made it difficult to identify watered-out zones with tr... The KT-II layer in the Zananor Oilfield,Caspian Basin,Kazakhstan,contains carbonate reservoirs of various types.The complex pore structure of the reservoirs have made it difficult to identify watered-out zones with traditional logging interpretation methods.This study classifies the reservoirs on the basis of core analysis and establishes an identification model for watered-out layers in the field to effectively improve the interpretation accuracy.Thin section analysis shows that there are three types of pores in the reservoirs,i.e.,the matrix pore,fracture and dissolution vug.A triple porosity model is used to calculate the porosities of the reservoirs and the results are combined with core analysis to classify the reservoirs into the fractured,matrix pore,fracture-pore as well as composite types.A classification standard is also proposed.There are differences in resistivity logging responses from the reservoirs of different types before and after watering-out.The preewatering-out resistivities are reconstructed using generalized neural network for different types of reservoirs.The watered-out layers can be effectively identified according to the difference in resistivity curves before and after watering-out.The results show that the watered-out layers identified with the method are consistent with measured data,thus serving as a reference for the evaluation of watered-out layers in the study area. 展开更多
关键词 watered-out zone Reconstructed resistivity Neural network Log evaluation Reservoir classification
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Evaluation of the Economical and Intensive Use of Industrial Land in Chizhou Economic and Technological Development Zone 被引量:3
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作者 Rui LIU 《Asian Agricultural Research》 2014年第10期85-90,共6页
Based on the subdivision of industrial land in Chizhou Economic and Technological Development Zone,this paper builds the evaluation indicator system for the economical and intensive use of industrial land in the devel... Based on the subdivision of industrial land in Chizhou Economic and Technological Development Zone,this paper builds the evaluation indicator system for the economical and intensive use of industrial land in the development zone,to analyze the current situation of economical and intensive use of industrial land. The results show that the levels of economical and intensive use of industrial land vary in the development zone; the factors affecting the intensive degree of various industries also vary; the industry in Chizhou Economic and Technological Development Zone is still in the transition phase from inefficient use to low level of use to intensive use. 展开更多
关键词 INDUSTRIAL LAND Economical and INTENSIVE use evalu
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Evaluation on Emergency Ability of Agricultural Envrironmental Pollution Incident in Central Plains Economic Zone
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作者 Chuai Xiaoming Yang Xiaoer +1 位作者 Zhou Haixia Zhang Yongling 《Meteorological and Environmental Research》 CAS 2015年第3期15-18,共4页
Abstract The level of emergency ability directly reflects response effect of an area to emergency. Taking Central Plains Economic Zone as re- search object, by documents retrieval, field survey, mechanism analysis and... Abstract The level of emergency ability directly reflects response effect of an area to emergency. Taking Central Plains Economic Zone as re- search object, by documents retrieval, field survey, mechanism analysis and logical reasoning, evaluation index system for emergency ability of ag- ricultural environmental pollution incident was established, which included 5 first grade indexes, 19 second grade indexes and 53 third grade inde- xes. By mechanism analysis and mathematical derivation, evaluation model for emergency ability of agricultural environmental pollution incident: I =m∑i=1∑j=1Pij, On this basis, four prefecture-level cities (A, B, C and D) of Central Plains Economic Zone were evaluated by using the index system and the evaluated model. The research could provide important theoretical reference for emergency ability construction of agricultural environmental pol- lution incident in Central Plains Economic Zone. 展开更多
关键词 Central Plains Economic zone Agricultural environmental pollution incident Emergency ability evaluation China
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Evaluation of Fragility of the Economic System in Poyang Lake Ecological Economic Zone
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作者 CHENG Qiao-zhen 1 ,CHEN Xiao-ling 1. 2 ,ZHU Feng-feng 1 ,ZHU Jing 1 1. School of Geography and Environment,Jiangxi Normal University,Nanchang 330022,China 2. State Key Laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,Wuhan 430022,China 《Asian Agricultural Research》 2012年第8期72-76,共5页
From two aspects,namely the sensitivity of regional economic system to internal and external interference,and its resilience,we establish the evaluation indicator system of fragility of the economic system in Poyang L... From two aspects,namely the sensitivity of regional economic system to internal and external interference,and its resilience,we establish the evaluation indicator system of fragility of the economic system in Poyang Lake Ecological Economic Zone,and evaluate the internal differences in fragility of the regional economic system,using set pair analysis method. The results show that there is a great difference in fragility of the economic system between different administrative units; the difference in resilience is the major factor responsible for difference in fragility of the economic system in various cities and counties within the region; according to the difference in fragility characteristics,we conduct classification as follows: Nanchang City is a low-sensitivity and high-resilience type; Jiujiang City is a high-sensitivity and high-resilience type; Jiujiang County,Xingzi County,Yongxiu County,Hukou County,Duchang County,Ruichang County,De'an Xian,Wuning County,Pengze County,Leping City, Dongxiang County,Fengcheng City and Gao'an City are a high-sensitivity and low-resilience type; other cities and counties are a low-sensitivity and low-resilience type. 展开更多
关键词 FRAGILITY evaluation The ECONOMIC SYSTEM Poyang LA
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The Stability Evaluation and Prospects about Environment Engineering Geologicalin Coastal Zone
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作者 MA Xue-ying 《科技视界》 2014年第24期209-209,共1页
The problems of environmental engineering geological in coastal zone mainly include earthquakes, collapse and landslide, etc. We selected eight major evaluation indexes from the influence factors of problems of enviro... The problems of environmental engineering geological in coastal zone mainly include earthquakes, collapse and landslide, etc. We selected eight major evaluation indexes from the influence factors of problems of environmental engineering geological in coastal zone, that is active fault, seismic activity and hydrological conditions, etc. Through the index of quantitative grading, constructing fuzzy comprehensive evaluation model,evaluation of environmental engineering geological stability in coastal zone, supplying a scientific method and gist for the more reasonable and effective development and utilization of coastal zone. 展开更多
关键词 海岸带 地质问题 环境工程 环境保护
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Pore structure effect on reservoir electrical properties and well logging evaluation 被引量:5
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作者 边环玲 关雎 +2 位作者 毛志强 鞠晓东 韩桂琴 《Applied Geophysics》 SCIE CSCD 2014年第4期374-383,508,共11页
The reservoir pore structure controls the reservoir quality and resistivity response of hydrocarbon-bearing zones and thus, critically affects logging interpretation. We use petrophysical data in three types of reserv... The reservoir pore structure controls the reservoir quality and resistivity response of hydrocarbon-bearing zones and thus, critically affects logging interpretation. We use petrophysical data in three types of reservoir with different pore structure characteristics to show that the complexity of pore structure had a significant effect on the effective porosity and permeability regardless of geological factors responsible for the formation of pore structure. Moreover,, the distribution and content of conductive fluids in the reservoir varies dramatically owing to pore structure differences, which also induces resistivity variations in reservoir rocks. Hence, the origin of low-resistivity hydrocarbon-bearing zones, except for those with conductive matrix and mud filtrate invasion, is attributed to the complexity of the pore structures. Consequently, reservoir-specific evaluation models, parameters, and criteria should be chosen for resistivity log interpretation to make a reliable evaluation of reservoir quality and fluids. 展开更多
关键词 pore structure reservoir quality RESISTIVITY low-resistivity hydrocarbon-bearing zone log evaluation
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Research on the evaluation of marine function zoning and its practice in China
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作者 黄南艳 王倩 +2 位作者 徐文斌 林宁 李萍 《Marine Science Bulletin》 CAS 2014年第1期38-50,共13页
The evaluation of marine function zoning (hereinafter referred to as MFZ) is an important part of MFZ. This paper studies the principles of MFZ evaluation and the evaluation procedures. It is proposed that three mai... The evaluation of marine function zoning (hereinafter referred to as MFZ) is an important part of MFZ. This paper studies the principles of MFZ evaluation and the evaluation procedures. It is proposed that three main aspects, including the evaluation of MFZ implementation situation, the evaluation of the performance effects and the evaluation of the changes of dependent conditions, are the top priorities in establishing an evaluation indicator system framework. The evaluation of MFZ implementation situation includes assessing the general situation of MFZ and the degree of implementation and public participation. The evaluation of the performance effects involves the assessments of the achievements and the existing problems in the rectification and standardization of utilizing the sea areas, protecting marine resources and environment, and promoting marine economic development. The evaluation of the changes of dependent conditions includes the assessments and measurements of the changes in the social and economic conditions, the use demands of marine industries, marine resource conditions and marine environmental conditions. This paper provides the means of integrating quantitative and qualitative approaches into the scientific and systematic evaluation on MFZ. The evaluation results can determine whether MFZ needs to be altered or not. The results also provide an important reference basis for determining whether a slight or great alteration is justified. To illustrate the utility of the MFZ evaluation indicator system, an evaluation example is given. Further studies are needed to make the evaluation of MFZ more scientific, reasonable, fair and effective. 展开更多
关键词 marine function zoning evaluation indicator system PRACTICE
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Evaluation of the relationship between hepatocellular carcinoma location and transarterial chemoembolization efficacy 被引量:8
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作者 Izumi Miki Satoru Murata +9 位作者 Fumio Uchiyama Daisuke Yasui Tatsuo Ueda Fumie Sugihara Hidemasa Saito Hidenori Yamaguchi Ryusuke Murakami Chiaki Kawamoto Eiji Uchida Shin-ichiro Kumita 《World Journal of Gastroenterology》 SCIE CAS 2017年第35期6437-6447,共11页
AIM To evaluate the relationship between the location of hepatocellular carcinoma(HCC) and the efficacy of transarterial chemoembolization(TACE).METHODS We evaluated 115 patients(127 nodules), excluding recurrent nodu... AIM To evaluate the relationship between the location of hepatocellular carcinoma(HCC) and the efficacy of transarterial chemoembolization(TACE).METHODS We evaluated 115 patients(127 nodules), excluding recurrent nodules, treated with TACE between January 2011 and June 2014. TACE efficacy was evaluated according to m RECIST. The HCC location coefficient was calculated as the distance from the central portal portion to the HCC center(mm)/liver diameter(mm) on multiplanar reconstruction images rendered(MPR) to visualize bifurcation of the right and left branches of the portal vein and HCC center. The HCC location coefficient was compared between complete response(CR) and non-CR groups in Child-Pugh grade A and B patients.RESULTS The median location coefficient of HCC among all nodules, the right lobe, and the medial segment was significantly higher in the CR group than in the non-CR group in the Child-Pugh grade A patients(0.82 vs 0.62, P < 0.001; 0.71 vs 0.59, P < 0.01; 0.81 vs 0.49, P < 0.05, respectively). However, there was no significant difference in the median location coefficient of the HCC in the lateral segment between in the CR and in the non-CR groups(0.67 vs 0.65, P > 0.05). On the other hand, in the Child-Pugh grade B patients, the HCC median location coefficient in each lobe and segment was not significantly different between in the CR and in the non-CR groups.CONCLUSION Improved TACE efficacy may be obtained for HCC in the peripheral zone of the right lobe and the medial segment in Child-Pugh grade A patients. 展开更多
关键词 Hepatocellular carcinoma LOCATION Transarterial CHEMOEMBOLIZATION EFFICACY CHILD-PUGH Modified response evaluation criteria in solid tumors Central zone Peripheral zone
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Monte Carlo Method for the Uncertainty Evaluation of Spatial Straightness Error Based on New Generation Geometrical Product Specification 被引量:10
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作者 WEN Xiulan XU Youxiong +2 位作者 LI Hongsheng WANG Fenglin SHENG Danghong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第5期875-881,共7页
Straightness error is an important parameter in measuring high-precision shafts. New generation geometrical product speeifieation(GPS) requires the measurement uncertainty characterizing the reliability of the resul... Straightness error is an important parameter in measuring high-precision shafts. New generation geometrical product speeifieation(GPS) requires the measurement uncertainty characterizing the reliability of the results should be given together when the measurement result is given. Nowadays most researches on straightness focus on error calculation and only several research projects evaluate the measurement uncertainty based on "The Guide to the Expression of Uncertainty in Measurement(GUM)". In order to compute spatial straightness error(SSE) accurately and rapidly and overcome the limitations of GUM, a quasi particle swarm optimization(QPSO) is proposed to solve the minimum zone SSE and Monte Carlo Method(MCM) is developed to estimate the measurement uncertainty. The mathematical model of minimum zone SSE is formulated. In QPSO quasi-random sequences are applied to the generation of the initial position and velocity of particles and their velocities are modified by the constriction factor approach. The flow of measurement uncertainty evaluation based on MCM is proposed, where the heart is repeatedly sampling from the probability density function(PDF) for every input quantity and evaluating the model in each case. The minimum zone SSE of a shaft measured on a Coordinate Measuring Machine(CMM) is calculated by QPSO and the measurement uncertainty is evaluated by MCM on the basis of analyzing the uncertainty contributors. The results show that the uncertainty directly influences the product judgment result. Therefore it is scientific and reasonable to consider the influence of the uncertainty in judging whether the parts are accepted or rejected, especially for those located in the uncertainty zone. The proposed method is especially suitable when the PDF of the measurand cannot adequately be approximated by a Gaussian distribution or a scaled and shifted t-distribution and the measurement model is non-linear. 展开更多
关键词 uncertainty evaluation Monte Carlo method spatial straightness error quasi particle swarm optimization minimum zone solution geometrical product specification
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Geometric Approximation Searching Algorithm for Spatial Straightness Error Evaluation 被引量:1
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作者 Jishun Li Xianqing Lei +1 位作者 Yujun Xue Weimin Pan 《Modern Instrumentation》 2013年第1期1-6,共6页
Considering the characteristics of spatial straightness error, this paper puts forward a kind of evaluation method of spatial straightness error using Geometric Approximation Searching Algorithm (GASA). According to t... Considering the characteristics of spatial straightness error, this paper puts forward a kind of evaluation method of spatial straightness error using Geometric Approximation Searching Algorithm (GASA). According to the minimum condition principle of form error evaluation, the mathematic model and optimization objective of the GASA are given. The algorithm avoids the optimization and linearization, and can be fulfilled in three steps. First construct two parallel quadrates based on the preset two reference points of the spatial line respectively;second construct centerlines by connecting one quadrate each vertices to another quadrate each vertices;after that, calculate the distances between measured points and the constructed centerlines. The minimum zone straightness error is obtained by repeating comparing and reconstructing quadrates. The principle and steps of the algorithm to evaluate spatial straightness error is described in detail, and the mathematical formula and program flowchart are given also. Results show that this algorithm can evaluate spatial straightness error more effectively and exactly. 展开更多
关键词 ERROR evaluation Spatial STRAIGHTNESS GEOMETRIC APPROXIMATION SEARCHING Algorithm Minimum zone
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Quantitative Evaluation of Ecological Cumulative Effects and Zoning Regulations for Prefectural Mining Units in China
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作者 MA Li KANG Lei +1 位作者 TIAN Huazheng XU Die 《Chinese Geographical Science》 SCIE CSCD 2022年第1期49-63,共15页
Although the development of energy and mineral resources strongly supports China’s rapid industrialization and urbanization,it has led to a series of ecological and environmental problems.Strengthening the spatial re... Although the development of energy and mineral resources strongly supports China’s rapid industrialization and urbanization,it has led to a series of ecological and environmental problems.Strengthening the spatial regulation considering the ecological and environmental protection on energy and mineral resource development areas is an important aspect of realizing China’s sustainable development.In this study,we mapped,categorized,and analyzed the ecological cumulative effects of the Chinese 134 prefectural mining units based on the pressure-state-response model,which is demonstrated as impact of mining activities on ecological environment,ecological environmental fragility,and ecological function.This investigation developed a stress zoning typology of the mining units based on scores of three dimensions of the ecological cumulative effects and classified 134 prefectural mining units into eight types of stress zones.A series of regulation and policy suggestions have been proposed to different types of zones from three aspects:space control,intensity control,and development mode control.The application of this evaluation and spatial zoning system will contribute to the refined spatial management of China’s mining areas. 展开更多
关键词 ecological cumulative effects quantitative evaluation pressure-state-response model ZONING
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Evaluation on Terrain-Climate Superiority Degree at County Level in Yunnan Province
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作者 Renyi YANG Zisheng YANG 《Asian Agricultural Research》 2021年第8期28-32,37,共6页
Terrain slope and climate zone(heat zone)are important factors affecting land use zoning and agricultural production layout in mountainous areas.Using"weight grade method",a quantitative index of comprehensi... Terrain slope and climate zone(heat zone)are important factors affecting land use zoning and agricultural production layout in mountainous areas.Using"weight grade method",a quantitative index of comprehensively evaluating terrain slope and climatic(thermal)conditions in mountainous areas was proposed:terrain-climate superiority degree(TCSD),and TCSD,terrain superiority degree(TSD),and climate superiority degree(CSD)in 129 counties(cities and districts)of Yunnan Province were measured and analyzed.The results showed that TCSD in 50.39%of counties of Yunnan Province was relatively better(levels I and II),and TCSD in 38.76%of counties was moderate(level III),while TCSD in 10.85%of counties was relatively poorer(levels IV and V). 展开更多
关键词 Terrain slope Climate zone Terrain-climate superiority degree County level evaluation
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Development and Evaluation of IPM Modules for the Management of Guava Fruit Fly
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作者 Mahesh Math Kotikal YK Venkateshalu 《Journal of Zoological Research》 2020年第2期1-5,共5页
Field studies were carried out during kharif 2016 and summer 2017 at Udyanagiri,UHS,Bagalkot,Karnataka,India to evaluate IPM modules against fruit fly in an already established guava orchard of variety Sardar(L-49).Am... Field studies were carried out during kharif 2016 and summer 2017 at Udyanagiri,UHS,Bagalkot,Karnataka,India to evaluate IPM modules against fruit fly in an already established guava orchard of variety Sardar(L-49).Among four modules,the mean fruit damage was significantly the lowest in M3(0.68%)followed by M2(1.19%)and M1(2.21%)and were on par with each other during kharif 2016.During summer 2017,M3 recorded significantly lowest damage(0.59%)followed by M2(0.92%)and M1(2.41%)but were on with each other.The highest per cent protection was afforded by M3(95.76 and 96.76,respectively)during 2016 and 2017.The average fruit yield over the years of experimentation revealed significantly the highest fruit yield(8.13 t/ha)from M3 followed by M2(7.32 t/ha)and M1(5.31 t/ha).Among the four modules,highest B:C was from M3(7.65)followed by M2(6.67)and M1(4.91). 展开更多
关键词 evaluation IPM modules GUAVA Fruit fly MANAGEMENT Northern dry zone
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Evaluation of Uncertainty of Earthquake Parameters for the Purpose of Seismic Zoning of Iran
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作者 Mirzaei Noorbakhsh,Gao Mengtan,and Chen YuntaiInstitute of Geophysics,SSB,Beijing 100081,China Institute of Geophysics,Tehran University,Tehran 14394,Iran 《Earthquake Research in China》 1997年第2期78-93,共16页
An efficient procedure is used for explicit description and evaluation of uncertainty of earthquake parameters in the uniform catalog of earthquakes in Iran and neighboring regions.An inadequate number of local and re... An efficient procedure is used for explicit description and evaluation of uncertainty of earthquake parameters in the uniform catalog of earthquakes in Iran and neighboring regions.An inadequate number of local and regional seismographic stations,poor station distribution,and Inadequacy of velocity models have resulted in conspicuous uncertainty in different parameters of recorded events.In a comprehensive seismic hazard analysis such uncertainties should be considered.Uncertainty of magnitude and location of events are evaluated for three different time periods,namely,historical,early instrumental,and modern instrumental time periods,for which existing seismological information differ widely in quantity,quality,and type.It is concluded that an uncertainty of 0.2-0.3 units of magnitude and 10-15 km in epicenter determinations should be considered in the most favorable conditions.None of the hypocenters of earthquakes in Iran can be considered as reliable,unless supported by other information such as 展开更多
关键词 evaluation of Uncertainty of Earthquake Parameters for the Purpose of Seismic Zoning of Iran ISC
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8个紫花苜蓿品种在干热区生产性能和营养价值评价 被引量:5
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作者 张德 龙会英 《中国草地学报》 CSCD 北大核心 2024年第1期70-77,共8页
为了筛选出适宜热带亚热带地区种植的苜蓿优良品种,在干热河谷区元谋,采用方差分析方法和灰色关联度分析方法,对2017年引进的8个紫花苜蓿品种进行生产性能和营养价值研究。结果表明:(1)参试的8个紫花苜蓿,在本区均能安全越冬,正常生长,... 为了筛选出适宜热带亚热带地区种植的苜蓿优良品种,在干热河谷区元谋,采用方差分析方法和灰色关联度分析方法,对2017年引进的8个紫花苜蓿品种进行生产性能和营养价值研究。结果表明:(1)参试的8个紫花苜蓿,在本区均能安全越冬,正常生长,生育期205~215 d。(2)株高最高的品种为WL525HQ,达到70.20 cm,与维多利亚、德钦、赛迪7号和WL712HQ品种有显著差异(P<0.05)。一级分枝数最高的品种为WL656品种,为27.20枝,WL712HQ和G8品种间有显著差异(P<0.05)。茎叶比最高的品种为WL712HQ品种,为1.10,与德钦和赛迪7号品种间有显著差异(P<0.05)。年均干草产量最高的是赛迪7号紫花苜蓿,显著高于德钦品种(P<0.05),2018年、2019年、2020年和三年的平均产量分别为34217.40 kg/hm^(2)、32527.55 kg/hm^(2)、22024.93 kg/hm^(2)和29589.96 kg/hm^(2),所有参试材料在2018年和2020年每年可刈割8次,2019年为9次。(3)5号品种粗蛋白和全磷含量显著高于其他品种(P<0.05),分别为21.43%和0.25%。WL903品种粗纤维含量显著高于其他品种(P<0.05),含量为23.51%。(4)经灰色关联度分析,8个紫花苜蓿品种排名前3的为赛迪7号、WL525HQ、维多利亚。综上,赛迪7号、‘WL-525HQ’、维多利亚表现较好,可在干热河谷区大面积推广应用。 展开更多
关键词 干热河谷 紫花苜蓿 生产性能 营养品质 评价
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氦气地质理论认识、资源勘查评价与全产业链一体化评价关键技术 被引量:3
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作者 陶士振 吴义平 +14 位作者 陶小晚 王晓波 王青 陈胜 高建荣 吴晓智 刘申奥艺 宋连腾 陈荣 李谦 杨怡青 陈悦 陈秀艳 陈燕燕 齐雯 《地学前缘》 EI CAS CSCD 北大核心 2024年第1期351-367,共17页
鉴于我国氦气产业链理论技术需求,针对国内外尚无系统的氦气地质理论认识,缺乏针对性的氦气资源评价方法、参数取值标准,缺乏氦气含量综合准确检测、有利富集区优选方法,无成本指标优化体系及全产业链一体化评价方法等卡点和难点,本文... 鉴于我国氦气产业链理论技术需求,针对国内外尚无系统的氦气地质理论认识,缺乏针对性的氦气资源评价方法、参数取值标准,缺乏氦气含量综合准确检测、有利富集区优选方法,无成本指标优化体系及全产业链一体化评价方法等卡点和难点,本文运用地质、地球化学、重磁电震、投资经济等多学科方法及实验技术,集中力量攻克氦气成藏机理、资源评价及资产评价的关键技术瓶颈。研发形成1项地质理论认识和3项关键技术:基于典型富氦气藏解剖、地下流体中“氦-气-水”相平衡及相-势耦合分析,研究提出氦气“水溶相、气容相、游离相”3种主要赋存状态、“集流、渗流、扩散”3种运移机理、“近氦源、邻断裂、低压区、高部位”4项分布富集控制因素,初步建立了基于“优质氦源、高效输导、适宜载体”的氦气“生-运-聚”地质理论认识。针对国内氦气含量检测技术参差不齐、部分准确度差、与国外数据差别大、无针对性的氦气资源评价方法等系列难题,以氦气源及氦气含量为核心,研发氦气含量综合准确检测技术,构建4类10种氦气资源评价方法,解决了氦气资源分级分类评价的技术瓶颈。针对基底氦源分布、岩性识别、通源断裂刻画及含氦储层评价难题,创建了归一化重磁下延方案,研发了基于深度学习的多尺度断裂智能识别技术和不同氦气含量下的气藏声学性质模拟方法,为氦源岩分布预测、通源断裂刻画、含氦储层测井解释评价及预测奠定了基础。通过建立多元控氦的富氦区带与目标优选技术,解决了富氦区带与目标优选难题。针对国内贫氦实际情况,以提氦装置投资和操作成本最小化为目标,采用响应面法建立优化目标与各主要工艺参数的非线性回归模型,建立了氦气全产业链一体化评价技术,初步解决了天然气低成本提氦工艺流程优化的技术需求。研究成果为我国长期、安全、规模利用氦气资源资产提供了有效支撑。 展开更多
关键词 氦气 氦源岩 氦气成藏机理 资源评价 区带目标优选 响应面法 深度学习 回归模型
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基于地质三维建模的矿床蚀变带深部资源预测方法 被引量:1
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作者 徐萍 宦长明 +3 位作者 贾磊 丁海红 陈鹏超 林迎洁 《矿产勘查》 2024年第6期1025-1031,共7页
随着矿产资源需求的持续增加,加之浅表矿产资源的逐渐匮乏,如何有效开发深部矿产资源成为国家重点研究课题之一。以往二维矿床信息无法确定精准的深部资源储量,阻碍矿产资源的开发进度,本文提出基于地质三维建模的矿床蚀变带深部资源预... 随着矿产资源需求的持续增加,加之浅表矿产资源的逐渐匮乏,如何有效开发深部矿产资源成为国家重点研究课题之一。以往二维矿床信息无法确定精准的深部资源储量,阻碍矿产资源的开发进度,本文提出基于地质三维建模的矿床蚀变带深部资源预测方法研究。应用地质三维建模软件(GOCAD)与计算机技术,构建矿床蚀变带深部地质三维模型,以此为基础,确定最佳单元尺度,划分矿床蚀变带深部地质统计单元,提取矿床蚀变带深部地质变量,计算地质变量权重数值,探究深部地质统计单元之间的联系度,基于三维证据权法预测矿床蚀变带深部资源。实验数据显示:应用该方法获得的矿床蚀变带深部资源预测误差最小值为1.01%,充分证实了该方法的深部资源预测精度更高。 展开更多
关键词 深部资源 矿床 定量预测 地质三维模型 蚀变带 资源预测评价
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