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Setting up State Holding Corporations——an Interview with He Boquan, Vice President of the China National Nonferrous Industry Corporation
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《China's Foreign Trade》 1995年第6期13-14,共2页
An announcement was made on November 4, 1994, on making the China National Nonferrous Industry Corporation one of the three State holding corporations for experiment at a national conference on experimenting on modern... An announcement was made on November 4, 1994, on making the China National Nonferrous Industry Corporation one of the three State holding corporations for experiment at a national conference on experimenting on modern enterprises sponsored by the State Council. The appearance of State holding corporations is the result of China’s deepening economic restructuring and an important and integral part of deepening enterprise reform. 展开更多
关键词 Vice President of the China National Nonferrous Industry Corporation setting up State Holding Corporations an Interview with He Boquan
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Unified Accreditation System Setting up in China
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《China's Foreign Trade》 2002年第9期47-47,共1页
关键词 Unified Accreditation System setting up in China
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Setting up Foundling Islands and the Protection of Children Rights
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作者 LIU HUAWEN 《The Journal of Human Rights》 2014年第5期24-28,共5页
Foundling islands are also called baby safety islands. Overseas they are also called foundling protection cabins and are a place to care for abandoned babies. In June 2011, the Shijiazhuang Social Welfare Institute in... Foundling islands are also called baby safety islands. Overseas they are also called foundling protection cabins and are a place to care for abandoned babies. In June 2011, the Shijiazhuang Social Welfare Institute in Hebei Province set up a foundling island. By the end of 2013, many cities had set up such islands, which is a new measure for ensuring children rights. 展开更多
关键词 setting up Foundling Islands and the Protection of Children Rights
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The Discussion of Setting up Accounting First Level Discipline
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作者 Cao Wei 《财会通讯(上)》 北大核心 2015年第1期4-4,共1页
Such disciplines as financial management,auditing,separated from the accounting diseipline system,have hecome anindependent professional,These two disciplines together with the original accounting diseipline,are liste... Such disciplines as financial management,auditing,separated from the accounting diseipline system,have hecome anindependent professional,These two disciplines together with the original accounting diseipline,are listed in business administration firstlevel discipline in the category of management,as the secondary discipline or professional.This paper argues that requirements are met now toset up the first level discipline of accounting professional(or class),and the three secondary discipline(or major):the accounting,financialmanagement,auditing,should be included into accounting first level discipline(or classes).Then,accounting will become first level disciplineparalleling with business administration first level. 展开更多
关键词 ACCOUNTING Subject setting First level subject
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Impact of setting distinct target blood glucose levels on endogenous insulin suppression and pharmacodynamics of insulin preparations
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作者 Hui Liu Ting Li +2 位作者 Xin-Lei Chen Hong-Ling Yu Ye-Rong Yu 《World Journal of Diabetes》 2025年第2期47-54,共8页
BACKGROUND Insulin therapy plays a crucial role in managing diabetes.Regulatory guidelines mandate assessing the pharmacokinetics(PK)and pharmacodynamics(PD)of new insulin formulations with euglycemic clamp techniques... BACKGROUND Insulin therapy plays a crucial role in managing diabetes.Regulatory guidelines mandate assessing the pharmacokinetics(PK)and pharmacodynamics(PD)of new insulin formulations with euglycemic clamp techniques before entry into the market.Typically,blood glucose(BG)levels are maintained at 5%below baseline to suppress endogenous insulin secretion in healthy volunteers.However,in scenarios where BG baseline is relatively low,maintaining it at 5%below baseline can increase hypoglycemic risk.Consequently,we adjusted to maintain it at 2.5%below a baseline of<4.00 mmol/L.It remains uncertain whether this adjustment impacts endogenous insulin inhibition or the PD of study insulin.AIM To evaluate and compare the PD and C-peptide status using two different target BG setting methods.METHODS Data came from euglycemic clamp trials assessing the PK/PD of insulin aspart(IAsp)in healthy participants.Target BG was set at 2.5%below baseline for those with a basal BG of<4.00 mmol/L(group A),and at 5%below baseline for others(group B).The area under the curve(AUC)of IAsp(AUC_(IAsp,0-8 h))and GIR from 0 to 8 hours(AUCGIR,0-8 h)was used to characterize the PK and PD of IAsp,respectively.The C-peptide reduction and PK/PD of IAsp were compared between the two groups.RESULTS Out of 135 subjects,15 were assigned to group A and 120 to group B;however,group B exhibited higher basal Cpeptide(1.59±0.36 vs 1.32±0.42 ng/mL,P=0.006).Following propensity score matching to adjust for basal Cpeptide differences,71 subjects(15 in group A and 56 in group B)were analyzed.No significant differences were observed in demographics,IAsp dosage,or clamp quality.Group B showed significantly higher baseline(4.35±0.21 vs 3.91±0.09 mmol/L,P<0.001),target(4.13±0.20 vs 3.81±0.08 mmol/L,P<0.001),and clamped(4.10±0.17 vs 3.80±0.06 mmol/L,P<0.001)BG levels.Both groups exhibited comparable C-peptide suppression(32.5%±10.0%vs 35.6%±12.1%,P=0.370)and similar IAsp activity(AUCGIR,0-8 h:1433±400 vs 1440±397 mg/kg,P=0.952)under nearly equivalent IAsp exposure(AUC_(IAsp,0-8 h):566±51 vs 571±85 ng/mL×h,P=0.840).CONCLUSION Maintaining BG at 2.5%below a baseline of<4.00 mmol/L did not compromise the endogenous insulin suppression nor alter the observed pharmacodynamic effects of the study insulin. 展开更多
关键词 Euglycemic clamp Target glucose setting Healthy subject C-PEPTIDE PHARMACODYNAMICS Endogenous insulin secretion
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Effects of acupuncture combined with bone-setting therapy to treat tourette syndrome:a three-arm randomized controlled trial
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作者 LANG Jiawang JIN Lingqing +1 位作者 LUO Jianchang LANG Boxu 《Journal of Traditional Chinese Medicine》 2025年第1期176-183,共8页
OBJECTIVE:To explore the efficacy and safety of acupuncture combined with atlantoaxial joint bone-setting therapy for the treatment of Tourette syndrome.METHODS:We randomly divided 600 patients at a ratio of 1∶1∶1 i... OBJECTIVE:To explore the efficacy and safety of acupuncture combined with atlantoaxial joint bone-setting therapy for the treatment of Tourette syndrome.METHODS:We randomly divided 600 patients at a ratio of 1∶1∶1 into three groups:group A(acupuncture combined with atlantoaxial joint bone setting therapy group),group B(acupuncture group),and group C(tiapride group).After two months of treatment,the Yale global tic severity scale(YGTSS)score reduction,improvement in social function impairment,clinical efficacy,and long-term efficacy in the three groups were compared.RESULTS:After treatment,in the analysis of YGTSS score reduction,social function impairment improvement,the clinical control rate,and long-term efficacy,the results were all Group A>Group B>Group C,with a statistically significant difference(P<0.05).However,the total clinical efficacy of treatment in group A(94.9%)was not significantly different from that in group B(91.8%).Adverse reactions did not occur in groups A and B,and several adverse reactions occurred in 29%(n=58)of the group C patients.CONCLUSION:Compared with traditional drug therapy,acupuncture combined with atlantoaxial joint bone setting therapy has better clinical and long-term efficacy.This treatment strategy can improve the social function of children and prevent adverse reactions to drugs. 展开更多
关键词 Tourette syndrome ACupUNCTURE atlanto-axial joint tiapride hydrochloride bone setting randomized controlled trial
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Noninvasive Breast Cancer Screening Strategies Supported by AI-Based Technologies in Resource-Limited Settings:Is It the Best Opportunity to Strengthen Women's Preferences,Values and Acceptability?
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作者 Wolmark Xiques-Molina Ivan David Lozada-Martinez +1 位作者 Ornella Fiorillo-Moreno Alexis Narvaez-Rojas 《Health Care Science》 2025年第4期310-313,共4页
Breast cancer is the leading cause of cancer-related mortality in women globally,with its incidence continuing to rise,particularly in low-and middle-income countries,presenting a significant public health challenge w... Breast cancer is the leading cause of cancer-related mortality in women globally,with its incidence continuing to rise,particularly in low-and middle-income countries,presenting a significant public health challenge worldwide[1].According to data from the Institute for Health Metrics and Evaluation(IHME)and the World Health Organization(WHO),the gap in access to healthcare services between high-and low-income countries contributes to delayed detection,increased incidence of advanced-stage disease,and,consequently,higher mortality rates(up to 50%higher compared to high-income countries)[1,2].This translates into inequalities in access to screening and early diagnosis methods,which exacerbate the burden of this disease in low-resource settings where infrastructure,funding,and access to trained professionals are limited[3]. 展开更多
关键词 breast neoplasms early detection of cancer mass screening resource-limited settings women's health services
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Designing a Protection Scheme in Micro-Grid Systems with DG Using Central Protection Unite and Multiple Setting Group Protection Relays 被引量:1
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作者 Mostafa I. Saleh Gaber El-Saady +1 位作者 Ali M. Yousef El-Noby A. Ibrahim 《Journal of Power and Energy Engineering》 2024年第9期37-49,共13页
Distributed generators now is widely used in electrical power networks, in some cases it works seasonally, and some types works at special weather conditions like photo voltaic systems and wind energy, and due to this... Distributed generators now is widely used in electrical power networks, in some cases it works seasonally, and some types works at special weather conditions like photo voltaic systems and wind energy, and due to this continuous changes in generation condition, the fault current level in network will be affected, this changes in fault current level will affect in the coordination between protection relays and to keep the coordination at right way, an adaptive protection system is required that can adaptive its setting according to generation changes, the fault current level in each case is evaluated using ETAP software, and the required relay setting in each case is also evaluated using Grey Wolf Optimizer (GWO) algorithm, and to select suitable setting which required in each condition, to select the active setting group of protection relay according to generation capacity, central protection unite can be used, and to improve protection stability and minimizing relays tripping time, a proposed method for selecting suitable backup relay is used, which leads to decrease relays tripping time and increase system stability, output settings for relays in all cases achieved our constrains. 展开更多
关键词 Directional Overcurrent Relay Protection Coordination Distributed Generators Central Protection Unite Multiple setting Group Protection Relay
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Mechanism Study on the Effect of Retarder on Polyurethane Setting Time Based on Molecular Simulation
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作者 WU Yuxuan XU Wenyuan +1 位作者 YU Tianlai JI Yongcheng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期224-231,共8页
This study identified castor oil and phosphate ester as effective retarders through setting time,tensile,and flexural tests,and determined their optimal dosages.The mechanism by which phosphate ester affects the setti... This study identified castor oil and phosphate ester as effective retarders through setting time,tensile,and flexural tests,and determined their optimal dosages.The mechanism by which phosphate ester affects the setting time of polyurethane was further investigated using molecular dynamics simulations.Fourier transform infrared spectroscopy was also employed to systematically study the physical and chemical interactions between phosphate esters and polyurethane materials.The results demonstrate that a 1%concentration of phosphate ester provides the most effective retarding effect with minimal impact on the strength of polyurethane.When phosphate ester is added to the B component of the two-component polyurethane system,its interaction energy with component A decreases,as do the diffusion coefficient and aggregation degree of component B on the surface of component A.This reduction in interaction slows the setting time.Additionally,the addition of phosphate ester to polyurethane leads to the disappearance or weakening of functional groups,indicating competitive interactions within the phosphate ester components that inhibit the reaction rate. 展开更多
关键词 POLYURETHANE RETARDER setting time molecular dynamics diffusion coefficient
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Solid Waste Management:A MADM Approach Using Fuzzy Parameterized Possibility Single-Valued Neutrosophic Hypersoft Expert Settings
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作者 Tmader Alballa Muhammad Ihsan +2 位作者 Atiqe Ur Rahman Noorah Ayed Alsorayea Hamiden Abd El-Wahed Khalifa 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期531-553,共23页
The dramatic rise in the number of people living in cities has made many environmental and social problems worse.The search for a productive method for disposing of solid waste is the most notable of these problems.Ma... The dramatic rise in the number of people living in cities has made many environmental and social problems worse.The search for a productive method for disposing of solid waste is the most notable of these problems.Many scholars have referred to it as a fuzzy multi-attribute or multi-criteria decision-making problem using various fuzzy set-like approaches because of the inclusion of criteria and anticipated ambiguity.The goal of the current study is to use an innovative methodology to address the expected uncertainties in the problem of solid waste site selection.The characteristics(or sub-attributes)that decision-makers select and the degree of approximation they accept for various options can both be indicators of these uncertainties.To tackle these problems,a novel mathematical structure known as the fuzzy parameterized possibility single valued neutrosophic hypersoft expert set(ρˆ-set),which is initially described,is integrated with a modified version of Sanchez’s method.Following this,an intelligent algorithm is suggested.The steps of the suggested algorithm are explained with an example that explains itself.The compatibility of solid waste management sites and systems is discussed,and rankings are established along with detailed justifications for their viability.This study’s strengths lie in its application of fuzzy parameterization and possibility grading to effectively handle the uncertainties embodied in the parameters’nature and alternative approximations,respectively.It uses specific mathematical formulations to compute the fuzzy parameterized degrees and possibility grades that are missing from the prior literature.It is simpler for the decisionmakers to look at each option separately because the decision is uncertain.Comparing the computed results,it is discovered that they are consistent and dependable because of their preferred properties. 展开更多
关键词 Hypersoft expert set Sanchez’s method decision making optimization solid waste management possibility grade fuzzy parameterization
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Petrographic and geochemical perspectives on sandstones of the extra-peninsular Gondwana Group from the Arunachal Himalayas,NE India:Probing provenance,tectonic context and paleoenvironmental conditions
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作者 Yadav Krishna Gogoi Pradip Borgohain +4 位作者 Diganta Bhuyan Devojit Bezbaruah Garima Konwar Manash Pratim Gogoi Bubul Bharali 《Acta Geochimica》 2025年第4期880-911,共32页
The extra-peninsular Gondwana Group rocks are exposed in narrow patches within the Lesser Himalayan sequence of the NE-Arunachal Himalayas,India.The bulk of sediments for the sandstones of the Gondwana Group were deri... The extra-peninsular Gondwana Group rocks are exposed in narrow patches within the Lesser Himalayan sequence of the NE-Arunachal Himalayas,India.The bulk of sediments for the sandstones of the Gondwana Group were derived from felsic/acidic to intermediate igneous rocks,with minor mafic input from the upper continental crust(UCC),as supported by various discrimination diagrams based on quantification of detrital minerals coupled with sandstone geochemistry.The inputs from metamorphic sources in subordinate amounts cannot be ruled out,as indicated by quantification of the quartz varieties.These sediments were found to be sourced from the interior part of a craton or shield and recycled platformal sediments which were derived from both passive and active margin settings.The sediments experienced a wide variance in climatic conditions,from arid to humid,suffering low-moderate-inten-sity weathering(CIA:63.43;CIW:86.18;WIP:44.84;PIA:75.37;ICV:2.39;C-value:0.42;PF:0.49;Sr/Cu:9.23 and Rb/Sr:1.68)within the vicinity of the low plains to moderate hills.Additionally,redox-sensitive elements indicate the deposition of sediments under oxygenated or oxygen-rich conditions(U_(au):−2.91;Th/U:7.37;U/Th:0.18;V/Cr:1.71;δU:0.67 and Ce/Ce^(*):0.93). 展开更多
关键词 GONDWANA GROup Arunachal HIMALAYAS PROVENANCE and TECTONIC setting Paleoclimate PALEOWEATHERING
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Petrogenetic and geochemical characteristics of some auriferous granitoids in the Kumasi Basin, Ghana: Implications for geodynamic settings and controls of orogenic gold mineralization in the Edikan Gold Mine
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作者 Emmanuel D.Sunkari Obed Oppong Theophilus K.Agbenyezi 《Deep Underground Science and Engineering》 2025年第3期406-421,共16页
The Edikan Mine,which consists of Fobinso and Esuajah gold deposits,lies within the Asankrangwa Gold Belt of the Birimian Supergroup in the Kumasi Basin.The metasedimentary rocks in the Basins and the faulted metavolc... The Edikan Mine,which consists of Fobinso and Esuajah gold deposits,lies within the Asankrangwa Gold Belt of the Birimian Supergroup in the Kumasi Basin.The metasedimentary rocks in the Basins and the faulted metavolcanic rocks in the Belts that make up the Birimian Supergroup were intruded by granitoids during the Eburnean Orogeny.This research aims to classify granitoids in the Edikan Mine and ascertain the petrogenetic and geochemical characteristics of some auriferous granitoids in the wider Kumasi Basin,Ghana,to understand the implications for geodynamic settings.A multi-methods approach involving field studies,petrographic studies,and whole-rock geochemical analysis was used to achieve the goal of the study.Petrographic studies revealed a relatively high abundance of plagioclase and a low percentage of K-feldspars(anorthoclase and orthoclase)in the Fobinso samples,suggesting that the samples are granodioritic in nature,while the Esuajah samples showed relatively low plagioclase abundance and a high percentage in K-feldspars,indicating that they are granitic.The granitoids from the study areas are co-magmatic.The granitoids in Esuajah and Fobinso are generally enriched in large ion lithophile elements and light rare earth elements than high field strength elements,middle rare earth elements,and heavy rare earth elements,indicating mixing with crustal sources during the evolution of the granitoids.The granitoids were tectonically formed in a syn-collisional+VAG setting,which implies that they were formed in the subduction zone setting.Fobinso granodiorites showed S-type signatures with evidence of extensive crustal contamination,while the Esuajah granites showed I-type signatures with little or no crustal contamination and are peraluminous.Gold mineralization in the study area is structurally and lithologically controlled with shear zones,faulting,and veining as the principal structures controlling the mineralization.The late-stage vein,V3,in the Edikan Mine is characterized by a low vein angle and is mineralized. 展开更多
关键词 Edikan Mine geodynamic setting GRANITOIDS lithologically controlled structurally controlled subduction zone
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Developing a diagnostic support system for audiogram interpretation using deep learning-based object detection
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作者 Titipat Achakulvisut Suchanon Phanthong +4 位作者 Thanawut Timpitak Kanpat Vesessook Sirinan Junthong Withita Utainrat Kanokrat Bunnag 《Journal of Otology》 2025年第1期26-32,共7页
Objective To develop and evaluate an automated system for digitizing audiograms,classifying hearing loss levels,and comparing their performance with traditional methods and otolaryngologists'interpretations.Design... Objective To develop and evaluate an automated system for digitizing audiograms,classifying hearing loss levels,and comparing their performance with traditional methods and otolaryngologists'interpretations.Designed and Methods We conducted a retrospective diagnostic study using 1,959 audiogram images from patients aged 7 years and older at the Faculty of Medicine,Vajira Hospital,Navamindradhiraj University.We employed an object detection approach to digitize audiograms and developed multiple machine learning models to classify six hearing loss levels.The dataset was split into 70%training(1,407 images)and 30%testing(352 images)sets.We compared our model's performance with classifications based on manually extracted audiogram values and otolaryngologists'interpretations.Result Our object detection-based model achieved an F1-score of 94.72%in classifying hearing loss levels,comparable to the 96.43%F1-score obtained using manually extracted values.The Light Gradient Boosting Machine(LGBM)model is used as the classifier for the manually extracted data,which achieved top performance with 94.72%accuracy,94.72%f1-score,94.72 recall,and 94.72 precision.In object detection based model,The Random Forest Classifier(RFC)model showed the highest 96.43%accuracy in predicting hearing loss level,with a F1-score of 96.43%,recall of 96.43%,and precision of 96.45%.Conclusion Our proposed automated approach for audiogram digitization and hearing loss classification performs comparably to traditional methods and otolaryngologists'interpretations.This system can potentially assist otolaryngologists in providing more timely and effective treatment by quickly and accurately classifying hearing loss. 展开更多
关键词 AUDIOGRAM Deep machine learning Training set Validation set Testing set Automatic Machine Learning(AutoML) Random Forest Classifier(RFC) Support Vector Machine(SVM) XGBoost
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Urban Transportation Strategy Selection for Multi-Criteria Group Decision-Making Using Pythagorean Fuzzy N-Bipolar Soft Expert Sets
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作者 Sagvan Y.Musa Zanyar A.Ameen +1 位作者 Wafa Alagal Baravan A.Asaad 《Computer Modeling in Engineering & Sciences》 2025年第9期3493-3529,共37页
Urban transportation planning involves evaluating multiple conflicting criteria such as accessibility,cost-effectiveness,and environmental impact,often under uncertainty and incomplete information.These complex decisi... Urban transportation planning involves evaluating multiple conflicting criteria such as accessibility,cost-effectiveness,and environmental impact,often under uncertainty and incomplete information.These complex decisions require input from various stakeholders,including planners,policymakers,engineers,and community representatives,whose opinions may differ or contradict.Traditional decision-making approaches struggle to effectively handle such bipolar and multivalued expert evaluations.To address these challenges,we propose a novel decisionmaking framework based on Pythagorean fuzzy N-bipolar soft expert sets.This model allows experts to express both positive and negative opinions on a multinary scale,capturing nuanced judgments with higher accuracy.It introduces algebraic operations and a structured aggregation algorithm to systematically integrate and resolve conflicting expert inputs.Applied to a real-world case study,the framework evaluated five urban transport strategies based on key criteria,producing final scores as follows:improving public transit(−0.70),optimizing traffic signal timing(1.86),enhancing pedestrian infrastructure(3.10),expanding bike lanes(0.59),and implementing congestion pricing(0.77).The results clearly identify enhancing pedestrian infrastructure as the most suitable option,having obtained the highest final score of 3.10.Comparative analysis demonstrates the framework’s superior capability in modeling expert consensus,managing uncertainty,and supporting transparent multi-criteria group decision-making. 展开更多
关键词 Pythagorean fuzzy N-bipolar soft expert sets N-soft sets pythagorean fuzzy sets MCGDM urban transportation
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Assessing GNSS hydrological monitoring capability across different climatic settings in China
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作者 Qingwen Huang Lilong Liu +3 位作者 Chaolong Yao Si Xiong Liangke Huang Tengxu Zhang 《Geodesy and Geodynamics》 2025年第2期147-157,共11页
Vertical position changes of ground-based Global Navigation Satellite System(GNSS) stations have been used to study regional terrestrial water storage(TWS) changes. However, the feasibility is still unclear in many ar... Vertical position changes of ground-based Global Navigation Satellite System(GNSS) stations have been used to study regional terrestrial water storage(TWS) changes. However, the feasibility is still unclear in many areas due to diverse local effects. This study aims to evaluate the capability of GNSS vertical displacements in monitoring hydrological variations in four climate settings over Chinese mainland. The spatial and temporal variations of hydrological load-induced(HYDL) vertical displacements at 208 GNSS sites during 2011-2020 were analyzed by comparing with Gravity Recovery and Climate Experiment(GRACE)/GRACE Follow-On(GFO) and Global Land Data Assimilation System(GLDAS) derived TWS changes. The results indicate that GNSS vertical positions show different capabilities in capturing seasonal and non-seasonal hydrological dynamics in different climate regions. Among the four climatic settings, the subtropical monsoon climate(SMC) region, with the largest deformation fluctuation(the regional mean root mean square(RMS) is 7.97 mm), has the highest regional mean HYDL-GRACE and HYDL-GLDAS anti-correlation coefficients(CCs) of-0.47 and-0.45 at the seasonal scale, respectively. For the individual GNSS site, the number of the sites with CC <-0.40 between HYDL and GRACE/GLDASderived TWS changes accounts for 55.1% and 55.1%(SMC), 13.0% and 7.4%(temperate monsoon climate, TMC), 6.7% and 13.3%(temperate continental climate, TCC), 32.3% and 38.7%(plateau climate,PC), respectively. For the non-seasonal term, although the proportion with CC <-0.40 in each climate type decreases mainly due to the influence of local geodynamic and human activities, especially in the SMC and PC regions, GNSS site vertical deformations still show good capability in monitoring hydrological extremes. The results provide valuable information for better application of GNSS to hydrology. 展开更多
关键词 GNSS vertical displacement Hydrological loading GRACE GLDAS Climate setting
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Petrogenesis and Geodynamic Setting of Paleoproterozoic Rocks from Zoukougbeu(Dalao,Central-Western Côte d’Ivoire):Insights from Petrography and Geochemistry
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作者 Koffi Alexis N’dri ZiandjêdéHervéSiagné +4 位作者 Brice Roland Kouassi Ibrahima Aminata Diaby MarcÉphrem Allialy Yaya Ouattara Gnanzou Allou 《International Journal of Geosciences》 2025年第11期871-889,共19页
The Paleoproterozoic basement of Zoukougbeu in central-western Côte d’Ivoire lies within the southern Baoulé-Mossi domain of the West African Craton,a key area for understanding the crustal evolution associ... The Paleoproterozoic basement of Zoukougbeu in central-western Côte d’Ivoire lies within the southern Baoulé-Mossi domain of the West African Craton,a key area for understanding the crustal evolution associated with the Eburnean orogeny.However,the petrogenesis and geodynamic context of the granitoid intrusions in this region remain poorly constrained,despite their potential sig nificance for regional crustal growth and mineralization.This study integrates petrographic and whole-rock geochemical data from drill-core samples to clar-ify the origin and tectonic evolution of these rocks.The lithological assemblage includes granodiorite,granite,diorite,gneiss,and pegmatite,variably deformed and hydrothermally altered.Petrographic analysis reveals plagioclase-quartzbiotiteamphibole assemblages overprinted by chlorite-epidote alteration,in-dicating greenschist-to amphibolite-facies metamorphism.Geochemically,the rocks define a calc-alkaline,metaluminous to slightly peraluminous suite with tonalite-trondhjemite-granodiorite(TTG)affinity.Their enrichment in largeion lithophile elements and depletion in Nb-Ta-Ti,coupled with LREE enrich-ment and negative Eu anomalies,are typical of subduction-related magmatism.These signatures indicate that the Zoukougbeu granitoids originated from par-tial melting of hydrated basaltic crust with minor mantle input in a continental volcanic-arc setting during the Eburnean orogeny(~2.1-2.0 Ga).This finding refines the current understanding of Paleoproterozoic crustal evolution in the southern West African Craton and highlights the role of arc magmatism in its stabilization. 展开更多
关键词 PETROGENESIS Geodynamic setting PETROGRAPHY GEOCHEMISTRY Côte d’Ivoire
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Geochronology and geodynamic setting of the carbonate-hosted Pb-Zn deposits in world-class Sichuan-Yunnan-Guizhou triangle,South China
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作者 Zhongxi Xue Wenxin Shi +2 位作者 Chen Wei Tao Wu Zhilong Huang 《Acta Geochimica》 2025年第1期217-230,共14页
Unraveling the precise mineralization age is vital to understand the geodynamic setting and ore-forming mechanism of the sediment-hosted Pb-Zn deposit;this has long been a challenge.The Sichuan-Yunnan-Guizhou(SYG)tria... Unraveling the precise mineralization age is vital to understand the geodynamic setting and ore-forming mechanism of the sediment-hosted Pb-Zn deposit;this has long been a challenge.The Sichuan-Yunnan-Guizhou(SYG)triangle in the southwestern margin of the Yangtze Block is a globally recognized carbonate-hosted Pb-Zn metallogenic province and also an essential part of the South China low-temperature metallogenic domain.This region has>30 million tons(Mt)Zn and Pb resources and shows the enrichment of dispersed metals,such as Ga,Ge,Cd,Se,and Tl.During the past 2 decades,abundant data on mineralization ages of Pb-Zn deposits within the SYG triangle have been documented based on various radioisotopic dating methods,resulting in significant progress in understanding the geodynamic background and ore formation of Pb-Zn deposits hosted in sedimentary rocks at SYG triangle.This paper provides a comprehensive summary of the geochronological results and Pb-Sr isotopic data regarding Pb-Zn deposits in the SYG triangle,which identified two distinct Pb-Zn mineralization periods influencing the dynamic processes associated with the expansion and closure of the Paleo-Tethys Ocean in the western margin of the Yangtze Block.The predominant phase of Pb-Zn mineralization at SYG triangle spanned from the Middle Triassic to Early Jurassic(226-191 Ma),which was intensely correlated with the large-scale basin fluid transport triggered by the closure of the Paleo-Tethys Ocean and Indosinian orogeny.The secondary Pb-Zn mineralization phase occurred during the Late Devonian to Late Carboniferous and was controlled by extensional structures associated with the expansion of the Paleo-Tethys Ocean.Further investigation is necessary to clarify the occurrence and potential factors involved in the Pb-Zn mineralization events during the Late Devonian to Late Carboniferous. 展开更多
关键词 Sichuan-Yunnan-Guizhou triangle Carbonate hosted Pb-Zn deposit Radioisotopic dating Geodynamic setting Mississippi Valley-type(MVT)
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Late-Silurian intraplate basalts from the southwestern margin of the Ordos Basin:Implication for decompression melting of metasomatized evolved mantle in extension setting
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作者 Dongxu Wang Hujun Gong +1 位作者 Jiangfeng Qin Fenhong Luo 《Acta Geochimica》 2025年第2期260-277,共18页
The Longshan orogenic belt is located in the southwestern margin of Ordos Basin at the junction zone between the Western Qinling and Northern Qilian orogenic belt.Voluminous Early Paleozoic magmatism in this area is o... The Longshan orogenic belt is located in the southwestern margin of Ordos Basin at the junction zone between the Western Qinling and Northern Qilian orogenic belt.Voluminous Early Paleozoic magmatism in this area is of key significance for determining the Early Paleozoic tectonic evolution and deep crust-mantle structure.Previous studies mainly focused on the Paleozoic granites;the coeval mafic rocks in this area are still poorly understood.A set of Late Silurian intraplate tholeiitic basalts has been discovered in Longshan area,providing key evidence for the mantle source and deep geodynamic background in this area.The Late Silurian Angou basalt has similar geochemical features as intraplate tholeiitic basalt,with high Na_(2)O/K_(2)O ratios(5.22-8.25),enriched in large ion lithophile elements and LREE.In combination with their relatively evolved Sr-Nd isotopic composition[^(87)Sr/^(86)Sr(i)=0.7128-0.7140;ε_(Nd)(t)=-5.55 to-3.40],it is suggested that it originated from decompression melting of metasomatized enriched mantle in extensional setting.These results indicate that the mantle source in the junction zone of the West Qinling-North Qilian orogenic belt evolved from depleted to enriched with the continuation of Proto-Tethys subduction from the Cambrian to the Silurian.These results are of great significance to understanding the genesis of contemporaneous granite and the crust-mantle interaction in the junction zone between the Western Qinling and Northern Qilian orogenic belt. 展开更多
关键词 Ordos basin Late Silurian Intraplate basalts Metasomatized enriched mantle Extensional setting
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Paleoproterozoic trench-distal back-arc setting origin of the Mahakoshal Basin,Central Indian Tectonic Zone(CITZ):Evidence from the geochemistry of the metabasalts
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作者 Kamaal Parvez M.E.A.Mondal +1 位作者 Iftikhar Ahmad Wamiq Mohammed Khan 《Acta Geochimica》 2025年第4期826-843,共18页
The present study of metabasalts was carried out to understand the mantle source and geodynamic setting of the Mahakoshal Group in the Central Indian Tectonic Zone.In this study,we present detailed field,petrography,a... The present study of metabasalts was carried out to understand the mantle source and geodynamic setting of the Mahakoshal Group in the Central Indian Tectonic Zone.In this study,we present detailed field,petrography,and whole rock geochemistry of the Mahakoshal metabasalts.The Mahakoshal metabasalts are sub-alkaline in nature and belong to the tholeiitic series of rocks.The variation in rareearth element patterns of metabasalts indicates the different degrees of partial melting at shallow as well as deeper depths.Further,Eu/Eu*varies from 0.8 to 1.1(except sample KP-144=0.3),Ce/Ce*varies from 0.97 to 1.05,showing no cerium anomaly,and Nb/Nb*ranges from 0.7 to 1.3(except KP-144=0.1).The magnesium number(Mg#)varies from 0.2 to 0.3,which is quite low,indicating the evolved nature of the metabasalts.The studied metabasalts show E-MORB to OIB-type affinities,which are placed in the trench-distal back-arc setting.The opening of the Mahakoshal Basin is due to retreating orogen in the accretionary orogen setting and is contemporaneous with the assembly of the Columbia Supercontinent(~2.1-1.8 Ga).Hence,field,petrographic,and geochemical signatures indicate that the Mahakoshal basin opened as a back-arc rift basin on the Bundelkhand Craton,and that metabasalts are derived from the mantle that underwent variable degrees of partial melting at different depths. 展开更多
关键词 Metabasalts Mahakoshal Basin Distaltrench back-arc setting Accretionary orogen Columbia supercontinent Central Indian Tectonic Zone(CITZ)
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Intelligent tool setting for vibration cutting process using machine vision and hearing
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作者 Zhihao Ma Junhao Zhao +2 位作者 Jiahui Liu Peiyuan Ding Jianjian Wang 《Nanotechnology and Precision Engineering》 2025年第3期1-7,共7页
Vibration cutting has emerged as a promising method for creating surface functional microstructures.However,achieving precise tool setting is a time-consuming process that significantly impacts process efficiency.This... Vibration cutting has emerged as a promising method for creating surface functional microstructures.However,achieving precise tool setting is a time-consuming process that significantly impacts process efficiency.This study proposes an intelligent approach for tool setting in vibration cutting using machine vision and hearing,divided into two steps.In the first step,machine vision is employed to achieve rough precision in tool setting within tens of micrometers.Subsequently,in the second step,machine hearing utilizes sound pickup to capture vibration audio signals,enabling fine tool adjustment within 1μm precision.The relationship between the spectral intensity of vibration audio and cutting depth is analyzed to establish criteria for tool–workpiece contact.Finally,the efficacy of this approach is validated on an ultra-precision platform,demonstrating that the automated tool-setting process takes no more than 74 s.The total cost of the vision and hearing sensors is less than$1500. 展开更多
关键词 Vibration cutting Automatic tool setting Machine vision Machine hearing
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