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The Results and Comparison of "Logical-Tree" Seismic Zoning in the Panxi Area
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作者 Zhang Yaoguo,Lei Jiancheng,Tang Rongchang,and Qian Hong Seismological Bureau of Sichuan Province,Chengdu 610041,China 《Earthquake Research in China》 1997年第3期66-74,共9页
On the basis of the technological route of seismic hazard analysis,the methods for determining seismicity parameters,such as b value,annual occurrence rate,and the seismic spatial distribution function,are discussed.T... On the basis of the technological route of seismic hazard analysis,the methods for determining seismicity parameters,such as b value,annual occurrence rate,and the seismic spatial distribution function,are discussed.Then,the seismic intensity zoning in Panxi area in Southwest China is carried out by applying the "logical-tree,"which is made up of multi-parameter schemes.It is clearly shown from the results that seismic intensity zoning is influenced by many uncertain factors and it is necessary to seek a certain balance between seismic safety and investment interest and a good way,with the present limited knowledge level,to obtain seismic intensity zoning is through the "logical-tree" method. 展开更多
关键词 The Results and Comparison of Seismic zoning in the Panxi Area Logical-Tree
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Prediction of the position of coal particles in an air dense medium fluidized bed system 被引量:5
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作者 Prusti Pallishree Sahu Ashok K. Biswal Surendra K. 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第3期421-427,共7页
An air dense medium fluidized bed separator(ADMFBS) is used for dry beneficiation of coal using ultrafine magnetite particles as a pseudo-fluid medium. In this process, the coal particle gains additional weight due to... An air dense medium fluidized bed separator(ADMFBS) is used for dry beneficiation of coal using ultrafine magnetite particles as a pseudo-fluid medium. In this process, the coal particle gains additional weight due to coating on its surface and deposition at dead zone area by fine magnetite particles.Hence, the effective density of coal particle increases and the position of coal particle changes accordingly. In this work, an attempt was made to predict the position of coal particle in non-bubbling condition dense medium fluidized bed system. Coal particles of different shape such as cubical, rectangular prism,spherical and triangular prism with different projected area and density were used. The results show that the position of coal particle in air dense medium fluidized bed follows descending order with respect to the increase of density, projected area of coal particle and different shapes(i.e., triangular prism, cubical,rectangular prism and spherical). Empirical mathematical correlations were developed to predict the position of coal particle. 展开更多
关键词 Coal beneficiation Pseudo-fluid medium Dead zone area Effective density
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A population-feedback control based algorithm for well trajectory optimization using proxy model 被引量:1
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作者 Javad Kasravi Mohammad Amin Safarzadeh Abdonabi Hashemi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2017年第2期281-290,共10页
Wellbore instability is one of the concerns in the field of drilling engineering.This phenomenon is affected by several factors such as azimuth,inclination angle,in-situ stress,mud weight,and rock strength parameters.... Wellbore instability is one of the concerns in the field of drilling engineering.This phenomenon is affected by several factors such as azimuth,inclination angle,in-situ stress,mud weight,and rock strength parameters.Among these factors,azimuth,inclination angle,and mud weight are controllable.The objective of this paper is to introduce a new procedure based on elastoplastic theory in wellbore stability solution to determine the optimum well trajectory and global minimum mud pressure required(GMMPR).Genetic algorithm(GA) was applied as a main optimization engine that employs proportional feedback controller to obtain the minimum mud pressure required(MMPR).The feedback function repeatedly calculated and updated the error between the simulated and set point of normalized yielded zone area(NYZA).To reduce computation expenses,an artificial neural network(ANN) was used as a proxy(surrogate model) to approximate the behavior of the actual wellbore model.The methodology was applied to a directional well in southwestern Iranian oilfield.The results demonstrated that the error between the predicted GMMPR and practical safe mud pressure was 4%for elastoplastic method,and 22%for conventional elastic solution. 展开更多
关键词 Elastoplastic theory Normalized yielded zone area(NYZA) OPTIMIZATION Well trajectory Proportional feedback controller Proxy model
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Estimation of soil reinforcement by the roots of four postdam prevailing grass species in the riparian zone of Three Gorges Reservoir, China 被引量:17
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作者 ZHONG Rong-hua HE Xiu-bin +5 位作者 BAO Yu-hai TANG Qiang GAO Jin-zhang YAN Dan-dan WANG Ming-feng LI Yu 《Journal of Mountain Science》 SCIE CSCD 2016年第3期508-521,共14页
Soil erosion and bank degradation is a major post-dam concern regarding the riparian zone of the Three Gorges Reservoir. The development and succession of vegetation is a main countermeasure,especially to enhance bank... Soil erosion and bank degradation is a major post-dam concern regarding the riparian zone of the Three Gorges Reservoir. The development and succession of vegetation is a main countermeasure,especially to enhance bank stability and mitigate soil erosion by the root system. In this study, the roots of four prevailing grass species, namely, Cynodon dactylon, Hemarthria altissima, Hemarthria compressa, and Paspalum paspaloides, in the riparian zone were investigated in relation to additional soil cohesion. Roots were sampled using a single root auger. Root length density(RLD) and root area ratio(RAR) were measured by using the Win RHIZO image analysis system. Root tensile strength(TR) was performed using a manualdynamometer, and the soil reinforcement caused by the roots was estimated using the simple Wu's perpendicular model. Results showed that RLD values of the studied species ranged from 0.24 cm/cm3 to20.89 cm/cm3 at different soil layers, and RLD were significantly greater at 0–10 cm depth in comparison to the deeper soil layers(&gt;10 cm). RAR measurements revealed that on average 0.21% of the reference soil area was occupied by grass roots for all the investigated species. The measured root tensile strength was the highest for P. paspaloides(62.26MPa) followed by C. dactylon(51.49 MPa), H.compressa(50.66 MPa), and H. altissima(48.81MPa). Nevertheless, the estimated maximum root reinforcement in this investigation was 22.5 k Pa for H.altissima followed by H. compressa(21.1 k Pa), P.paspaloides(19.5 k Pa), and C. dactylon(15.4 k Pa) at0–5 cm depth soil layer. The root cohesion values estimated for all species were generally distributed at the 0–10 cm depth and decreased with the increment of soil depth. The higher root cohesion associated with H. altissima and H. compressa implies their suitability for revegetation purposes to strengthen the shallow soil in the riparian zone of the Three Gorges Reservoir. Although the soil reinforcement induced by roots is only assessed from indirect indicators, the present results still useful for species selection in the framework of implementing and future vegetation recovery actions in the riparian zone of the Three Gorges Reservoir and similar areas in the Yangtze River Basin. 展开更多
关键词 Bank stabilization Root area ratio Root tensile strength Soil reinforcement Riparian zone Three Gorges Reservoir
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Evaluation of macular choroidal and microvascular network changes by activity scores and serum antibodies in thyroid eye patients and healthy subjects
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作者 Mehmet Erkan Dogan Ibrahim Basol +2 位作者 Hatice Deniz Ilhan Yusuf Ayaz Olgar Ocal 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第12期2089-2094,共6页
AIM:To investigate the choroidal thickness and the microvascular network changes around the macula in thyroid eye disease(TED)patients at different stages and the relationship of those changes with risk factors,serum ... AIM:To investigate the choroidal thickness and the microvascular network changes around the macula in thyroid eye disease(TED)patients at different stages and the relationship of those changes with risk factors,serum antibodies and the severity of TED.METHODS:A total of 85 participants were enrolled.All participants underwent ophthalmology and endocrinology examinations.Subfoveal choroidal thickness(SFCT),superficial(s)and deep(d)foveal avascular zone(FAZ)area,mean(m)and central(c)superficial vascular density(SVD),deep vascular density(DVD)measurements of the enrolled cases were performed with Topcon swept source optical coherence tomography(OCT)/OCT angiography(OCTA)DRI OCT Triton.Multiple linear regression analysis was used to explore the associations between SFCT,FAZ area,SVD,DVD and the relevant factors of TED.RESULTS:Those with active TED patients had higher c-DVD and m-DVD levels(P<0.05),however there is no statistically significant difference in SFCT between active and stable TED patients.Among the serum antibodies,it was observed that s-FAZ and d-FAZ increased,c-SVD and m-SVD decreased in patients with high thyroid stimulating hormone-receptor autoantibodies(TRAB)level,whereas SFCT thickened in patients with high levels of both TRAB and human thyroglobulin(hTG).There was no significant difference in SFCT,FAZ,SVD and DVD measurement at gender,between hyperthyroid and euthyroid patients and among those with or without thyroid papillary carcinoma.CONCLUSION:The results show that both disease activation and serum antibodies differentially affect both superficial and deep retinal vascular density.It has also been shown that high serum antibody levels affect choroidal thickness independent of clinical activity. 展开更多
关键词 thyroid eye disease optic coherence tomography angiography vascular density choroidal thickness foveal avascular zone area
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Petroleum Pollution of Groundwater in Zibo and Its Prevention Measures 被引量:1
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作者 徐建芳 武强 李铎 《Journal of China University of Mining and Technology》 2003年第1期24-28,共5页
The source of ground water supply in Dawu is an extremely huge one in Shandong province. Now it is faced with serious pollution of petroleum in Hougao area. Aiming at this problem, the petroleum pollution in aeration ... The source of ground water supply in Dawu is an extremely huge one in Shandong province. Now it is faced with serious pollution of petroleum in Hougao area. Aiming at this problem, the petroleum pollution in aeration zone and in groundwater was analyzed. The result shows that the contaminant of groundwater comes from the leaching of petroleum in the soil horizon of aeration zone through precipitation, and the quick flow of groundwater makes the convection dominate themigration of contaminant. So movement of groundwater controls the distribution of petroleum contaminant, which is consistent with the direction of ground flow. Building a groundwater closure zone in Hougao is an effective method to stop the contaminated groundwater flowing toward the water supply source of Dawu. The petroleum contaminant can be effectively reduced through using the aeration, biological and oxidation technologies. 展开更多
关键词 Groundwater source Dawu area Petroleum pollution Groundwater closure zone aeration biological and oxidation technology
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Temporal variation of gravity field prior to the Ludian Ms6.5 and Kangding Ms6.3 earthquakes 被引量:3
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作者 Hao Hongtao Wei Jin +2 位作者 Hu Minzhang Liu Ziwei Li Hui 《Geodesy and Geodynamics》 2015年第6期429-436,共8页
Using mobile gravity data from the central area of Sichuan and Yunnan Provinces, the relationship between gravity variation and earthquakes was studied based on the Ludian Ms6.5 earthquake that occurred on August 3rd,... Using mobile gravity data from the central area of Sichuan and Yunnan Provinces, the relationship between gravity variation and earthquakes was studied based on the Ludian Ms6.5 earthquake that occurred on August 3rd, 2014, and the Kangding Ms6.3 earthquake that occurred on November 22 nd, 2014; the mechanism of gravity variation was also explored. The results are as follows:(1) Prior to both earthquakes, gravity variation exhibited similar characteristics as those observed before both the Tangshan and Wenchuan earthquakes, in which typical precursor anomalies were positive gravity variation near the epicenter and the occurrence of a high-gravity-gradient zone across the epicenter prior to the earthquake.(2) A relatively accurate prediction of the occurrence locations of the two earthquakes was made by the Gravity Network Center of China(GNCC) based on these precursor anomalies. In the gravity study report on the 2014 earthquake trends submitted at the end of 2013, the Daofu-Shimian section at the junction of the Xianshuihe and Longmenshan fault zones was noted as an earthquake-risk region with a predicted magnitude of 6.5, which covered the epicenter of the Kangding Ms6.3 earthquake. In another report on earthquake trends in southwestern China submitted in mid-2014, the Lianfeng, Zhaotong fault zone was also classified as an earthquake-risk region with a magnitude of 6.0, and the central area of this region basically overlapped with the epicenter of the Ludian Ms6.5 earthquake.(3) The gravity variation characteristics are reasonably consistent with crustal movements, and deep material migration is likely the primary cause of gravity variation. 展开更多
关键词 Ludian Ms6.5 earthquake Kangding Ms6.3 earthquak Gravity variation Gradient zone Mechanism of gravity variation Crustal movement Deep material migration Sichuan-Yunnan area
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Evaluation of childhood developing via optical coherence tomography-angiography in Qamdo,Tibet,China:A prospective cross-sectional,school-based study
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作者 Ke-Xin Sun Yong-Guo Xiang +7 位作者 Tong Zhang Sheng-Lan Yi Jiu-Yi Xia Xin Yang Shi-Jie Zheng Yan Ji Wen-Juan Wan Ke Hu 《World Journal of Clinical Cases》 SCIE 2023年第23期5479-5493,共15页
BACKGROUND Optical coherence tomography angiography(OCTA)is a new and reliable machine used to evaluate retinal structure and macular perfusion in children.The use of OCTA under bad condition such as high altitude,low... BACKGROUND Optical coherence tomography angiography(OCTA)is a new and reliable machine used to evaluate retinal structure and macular perfusion in children.The use of OCTA under bad condition such as high altitude,low atmospheric oxygen,and low humidity,in children is rarely.AIM To quantify the macular micro-vasculature in healthy children of various ages using OCTA in Qamdo.METHODS Design:Prospective cross-sectional,school-based study.Three hundred and fortyseven normal students from 9 schools in 4 different areas in Qamdo were included.OCTA was performed on a 3 mm×3 mm area centered on the macular region and macular cube 512×128 showed details in macular.Early treatment of diabetic retinopathy study Vessel Flow Density(VD)of the macular central vascular plexus density(CVD),inner vascular plexus density(IVD),full vascular plexus density(FVD),and the size of the foveal avascular zone(FAZ)were measured.All these results corrected by t/s=3.382×0.01306×(axial length-1.82).The differences were compared among various ages,sexes and living environments.RESULTS The mean FAZ area in all eyes was 0.27 mm^(2)±0.12 mm^(2).The mean foveal thickness(MFT)in the macular cube was 227.64μm±23.51μm.Compared with girls,boys had a lager FAZ(P=0.0029).Among the different age groups,MFT(P<0.001)and FVD(P<0.0001),IVD(P<0.0001),and CVD(P=0.0050)increased with age.FAZ areas were not correlated with age(P=0.8853)or others(MFT,area).CONCLUSION OCTA can use to evaluate macular perfusion in children.Our data bridge the gap between structural OCT and perfusion density in children in high altitude.Even though these were not a longitudinal study,it may provide us with hints about retina development during puberty and clinical implications of OCTA in children. 展开更多
关键词 Optical coherence tomography-angiography Qamdo Foveal avascular zone area Vessel flow density TEENAGER
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DEVELOPING BOHAI SEA ZONE AND TIANJIN INTO A METROPOLITAN AREA IN THE EAST ASIAN & ASIA-PACIFIC ECONOMIC BELT
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作者 Gu Shutang Jie Tang Professor of Economics. First Deputy Director of the Institute of Economics of NAKAI UNIVERSITY Ph. D. of Economics. Associate Professor of Institute of Economics of NANKAI UNIVERSITY 《南开经济研究》 CSSCI 北大核心 1994年第S3期2-7,18,共7页
Compared with the stagnanteconomy of the rest world,Asian-Pa-cific economy has been experiencingthe hightest growth since the 1980s.Now,most researchers and officials,and even entrepreneurs believe
关键词 ASIA-PACIFIC ECONOMIC BELT DEVELOPING BOHAI SEA ZONE AND TIANJIN INTO A METROPOLITAN AREA IN THE EAST ASIAN EAST more Asia SEA
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Evaluation System and Method of Industrial Park Renewal:A Case Study of the Starting Area of Handan City
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作者 ZHAO Ping GAO Ruihong +1 位作者 XUE Xiaona LI Wenya 《Journal of Landscape Research》 2022年第4期29-32,38,共5页
With the rapid development of urbanization,the industrial parks originally located in the suburbs are gradually incorporated into the urban center.Industries that fail to follow the transformation of urban economic de... With the rapid development of urbanization,the industrial parks originally located in the suburbs are gradually incorporated into the urban center.Industries that fail to follow the transformation of urban economic development and are forced to close,or enterprises that move out without conforming to the environment,become a gray area within the city.Most of the existing assessments are conducting single assessment of some indicators,but than their actual benefits.Through the field investigation on the starting area of Handan Economic Development Zone,and the evaluation on the nature of land use,development intensity,investment and output,and idle land,inefficient land use in the park is identified.According to different evaluation results,different update and promotion methods are put forward.The research could provide a new evaluation method and idea for subsequent renewal and development of urban industrial parks. 展开更多
关键词 Industrial park Inefficient land use Land use assessment Starting area of Economic Development Zone
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Territorial and Urban Evolution of Economic Zone along Durresi Street(Kamza Junction-Kashar Turn)
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作者 Agron Lufi Ogri Mane 《Journal of Civil Engineering and Architecture》 2022年第8期375-392,共18页
The territorial expansion of the economic zones along Tirana-Durres corridor,is considered as clear evidence of regional economic development.Since the first 10 years of 1990-2000,the need for a functional planning pr... The territorial expansion of the economic zones along Tirana-Durres corridor,is considered as clear evidence of regional economic development.Since the first 10 years of 1990-2000,the need for a functional planning process was clearly noted.In the early 2000’s,the linear planning on both sides of the highway,from KJ(Kamza Junction)to KT(Kashar Turn),was the real demonstration of that need.This article is a first effort towards an indirect analysis on spatial urban development processes of the last 20 years,indicated by development urban plans for Greater Tirana.This analysis concludes on the defects on integration of this area into the existing structure of Tirana,which are reflected in the new regulatory plans during 2012-2016.This article identifies the functional zoning phenomena,forms and rates of parcels occupation,analyzed through the land use indicators coverage.The urban analysis is focused also on identifying the achievements and failures on the design of spatial structures of social importance.This analysis intends to lead towards a more detailed study of the ways that enable the integration of this industrial area with the residential zone.It is considered as an attempt,which raises a number of issues,for helping the planners,architects and city administrators,involved in the planning and implementation of Partial Urban Plans. 展开更多
关键词 Industrial area/zone industrial park functional and zoning planning urban indicators of land use
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The Fast Road of Shale Gas Development in China——Reflections on Building a Special Test Areas for National Shale Gas Development 被引量:1
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作者 Da-wei Zhang 《Frontiers of Engineering Management》 2015年第4期364-372,394,共10页
China's shale gas development has had a good start. It is necessary that the developers take advantage of the opportunity to make further efforts to promote shale gas development in China, in particular by rolling... China's shale gas development has had a good start. It is necessary that the developers take advantage of the opportunity to make further efforts to promote shale gas development in China, in particular by rolling out a comprehensive plan on a national level. The author makes a proposal to establish a special shale gas test area in and adjacent to the Sichuan Basin as the most important way to promote the rapid development of shale gas in China. For this purpose, the author analyzes the current situation and problems of shale gas development in China, addresses the necessity and feasibility of establishing a special test area for shale gas development, and draws up the scope of this shale gas special test area of about 450 thousand square kilometers, covering Sichuan, Chongqing, Guizhou, and part of Yunnan, Hunan, Hubei provinces, and proposes the establishment of a shale gas test area in China. This consists of an overall plan, targets, and contents in 10 aspects, along with organization and implementation modes. The shale gas exploration and development in the shale gas zones is promoted vigorously by introducing special policies and innovating exploration, development and utilization model. While at the same time, the shale gas zones of continental facies in the Ordos Basin and marineterrigenous facies in South Hubei Basin will be established.The experiences of the reform in the shale gas zones will be the good practice for the reform of petroleum organization system. 展开更多
关键词 China shale gas exploration and development REFORM special shale gas test area(shale gas zone)
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羌塘高原无人区边缘地带人类聚落布局的社会经济根源--针对三个典型县的比较研究
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作者 张海朋 刘卫东 +2 位作者 刘志高 程汉 刘汉初 《Journal of Geographical Sciences》 SCIE CSCD 2023年第3期655-680,共26页
Human activities in the marginal zone of the Changtang Plateau(CTP)uninhabited area are important research topics in China and globally.Based on the core-periphery theory of geography,this paper selected three countie... Human activities in the marginal zone of the Changtang Plateau(CTP)uninhabited area are important research topics in China and globally.Based on the core-periphery theory of geography,this paper selected three counties in the marginal zone of the CTP uninhabited area with significant transitional physical geography features and socio-economic conditions as case areas.We used the data set of settlement patches identified by visual interpretation in Google Earth Pro,combining them with field survey data to study the evolution of human settlements on the CTP,the characteristics of settlement layout,and their socio-economic roots.The study found that:(1)Since the democratic reform in Tibet,the production mode of herders on the CTP has transitioned from four-season nomadic herding to cold-season sedentary grazing,warm-season rotational grazing,and then to a combination of sedentary grazing and forage supplementation.In structural changes of grassroots organizations,village boundaries were clarified,grazing ranges were fixed,and settlement systems were formed.(2)On a large scale,the settlement layout on the CTP showed a certain degree of agglomeration in local areas,but the settlements’spatial agglomeration decreased as the observation scale decreased.The settlement size structure matched the typical rank-size rule of rural settlements.(3)The settlement layout of the CTP showed significant traffic lines and dominant location orientation.These orientation characteristics revealed“core-periphery”regional differences.Changes in production conditions,such as artificial grass cultivation and part-time employment,affected the dependence on traditional grazing points.Settlements moved from resource dependence to dependence on multiple elements,such as resources and facilities.The religious,cultural heritage of the sacred mountains,lakes,and temples influenced the settlement layout,leading to clustering in local areas and to group format.This study expands our understanding of the settlement pattern in the marginal zone of uninhabited areas and provides valuable references for advancing the optimization of the CTP human settlement system in the new era. 展开更多
关键词 Changtang Plateau marginal zone of uninhabited area SETTLEMENT socio-economic elements Qinghai-Tibet Plateau human-land relationship
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