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澳洲坚果主导品种Own Choice的品种配置研究
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作者 孔广红 陶丽 +3 位作者 贺熙勇 倪书邦 陈丽兰 肖晓明 《中国南方果树》 北大核心 2024年第5期74-79,共6页
为了明确澳洲坚果园主导品种Own Choice(O.C)的最适配置品种,选择HAES863、D、D4、HAES816、HAES906、HAES294、HAES900、A4等8个品种为O.C授粉,统计分析不同授粉处理的着果率、杂交不亲和性程度指数、着果花序率、每果序着果数、落果... 为了明确澳洲坚果园主导品种Own Choice(O.C)的最适配置品种,选择HAES863、D、D4、HAES816、HAES906、HAES294、HAES900、A4等8个品种为O.C授粉,统计分析不同授粉处理的着果率、杂交不亲和性程度指数、着果花序率、每果序着果数、落果率、壳果横径等指标。结果表明,以着果率及着果花序率统计的杂交不亲和性程度指数发现,HAES863、D、D4、HAES816、HAES906与O.C的杂交亲和性高于A4、HAES294、HAES900。供试品种处理的着果率与着果花序率之间存在正相关关系,初步推断可使用着果花序率代替着果率评价O.C与不同品种的杂交不亲和性程度;8个授粉处理的平均着果花序率为40.60%,可以此推断O.C与不同授粉品种的田间杂交不亲和性程度。综合分析推断,澳洲坚果主导品种O.C的最适配置品种为HAES863和D4,根据小气候可选择性搭配种植D、HAES906、HAES816。 展开更多
关键词 澳洲坚果 Own choice 授粉品种 着果率 着果花序率 杂交不亲和性
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Genesis of LCT Pegmatites during Early Paleozoic Orogeny of the North Qinling Orogenic Belt,China:Emplacement Conditions and Structural Control 被引量:1
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作者 CEN Jubiao FENG Yonggang +6 位作者 LIANG Ting WANG Mengxi ZHANG Jianxin TAN Xijuan ZHANG Jie GAO Jinggang HE Lei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第5期1226-1243,共18页
The Guanpo pegmatite field in the North Qinling orogenic belt(NQB),China,hosts the most abundant LCT pegmatites.However,their emplacement conditions and structural control remain unexplored.In this contribution,we inv... The Guanpo pegmatite field in the North Qinling orogenic belt(NQB),China,hosts the most abundant LCT pegmatites.However,their emplacement conditions and structural control remain unexplored.In this contribution,we investigated it combining pegmatite orientation measurement with oxygen isotope geothermometry and fluid inclusion study.The orientations of type A1 pegmatites(P_(f)<σ_(2))are predominantly influenced by P-and T-fractures due to simple shearing in Shiziping dextral thrust shear zone during D_(2)deformation,whereas type A2 pegmatites(contemporaneous with D_(4))are governed by hydraulic fractures aligned with S_(0)and S_(0+1)stemming from fluid pressure(P_(f)<σ_(2)).Additionally,type B pegmatites(P_(f)≤σ_(2))exhibit orientations shaped by en echelon extensional fractures in local ductile shear zones(contemporaneous with D_(3)).The albite-quartz oxygen isotope geothermometry and microthermometric analysis of fluid inclusions in elbaites from the latest pegmatites(including types B and A2)suggest that the crystallization P-T for late magmatic and hydrothermal stages are 527.5-559.2℃,320℃,3.1-3.6 kbar and 2.0 kbar,respectively.Our observations along with previous studies suggest that the genesis of the LCT pegmatites was a long-term,multi-stage event during early Paleozoic orogeny(including the collision stage)of the NQB,and was facilitated by various local fractures. 展开更多
关键词 LCT pegmatite emplacement mechanism emplacement condition oxygen isotope geothermometry fluid inclusion North Qinling orogenic belt
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Influence of Family Financial Conditions on the Choice of Family Parenting Style : An Empirical Study Based on CEPS Data
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作者 Yifeng LANG 《Asian Agricultural Research》 2023年第8期19-23,共5页
As an important factor affecting the accumulation of children s human capital,family parenting style is of great significance to the future development of filial generation.Based on China s social reality,the study in... As an important factor affecting the accumulation of children s human capital,family parenting style is of great significance to the future development of filial generation.Based on China s social reality,the study investigated the influence of family financial conditions on the choice of family parenting style by using the data of CEPS2013-2014.The results showed that the improvement of family financial conditions significantly increased the intensity of the parenting style chosen by the family,and parents would have higher requirements for their children s daily study and life.Moreover,such impact varied among different classes and regions. 展开更多
关键词 Family financial conditions Family parenting style CEPS
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Discrete Choice Models and Artificial Intelligence Techniques for Predicting the Determinants of Transport Mode Choice--A Systematic Review
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作者 Mujahid Ali 《Computers, Materials & Continua》 SCIE EI 2024年第11期2161-2194,共34页
Forecasting travel demand requires a grasp of individual decision-making behavior.However,transport mode choice(TMC)is determined by personal and contextual factors that vary from person to person.Numerous characteris... Forecasting travel demand requires a grasp of individual decision-making behavior.However,transport mode choice(TMC)is determined by personal and contextual factors that vary from person to person.Numerous characteristics have a substantial impact on travel behavior(TB),which makes it important to take into account while studying transport options.Traditional statistical techniques frequently presume linear correlations,but real-world data rarely follows these presumptions,which may make it harder to grasp the complex interactions.Thorough systematic review was conducted to examine how machine learning(ML)approaches might successfully capture nonlinear correlations that conventional methods may ignore to overcome such challenges.An in-depth analysis of discrete choice models(DCM)and several ML algorithms,datasets,model validation strategies,and tuning techniques employed in previous research is carried out in the present study.Besides,the current review also summarizes DCM and ML models to predict TMC and recognize the determinants of TB in an urban area for different transport modes.The two primary goals of our study are to establish the present conceptual frameworks for the factors influencing the TMC for daily activities and to pinpoint methodological issues and limitations in previous research.With a total of 39 studies,our findings shed important light on the significance of considering factors that influence the TMC.The adjusted kernel algorithms and hyperparameter-optimized ML algorithms outperform the typical ML algorithms.RF(random forest),SVM(support vector machine),ANN(artificial neural network),and interpretable ML algorithms are the most widely used ML algorithms for the prediction of TMC where RF achieved an R2 of 0.95 and SVM achieved an accuracy of 93.18%;however,the adjusted kernel enhanced the accuracy of SVM 99.81%which shows that the interpretable algorithms outperformed the typical algorithms.The sensitivity analysis indicates that the most significant parameters influencing TMC are the age,total trip time,and the number of drivers. 展开更多
关键词 Machine learning techniques AI transport mode choice discrete choice model sustainable transportation
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A comparison of model choice strategies for logistic regression
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作者 Markku Karhunen 《Journal of Data and Information Science》 CSCD 2024年第1期37-52,共16页
Purpose:The purpose of this study is to develop and compare model choice strategies in context of logistic regression.Model choice means the choice of the covariates to be included in the model.Design/methodology/appr... Purpose:The purpose of this study is to develop and compare model choice strategies in context of logistic regression.Model choice means the choice of the covariates to be included in the model.Design/methodology/approach:The study is based on Monte Carlo simulations.The methods are compared in terms of three measures of accuracy:specificity and two kinds of sensitivity.A loss function combining sensitivity and specificity is introduced and used for a final comparison.Findings:The choice of method depends on how much the users emphasize sensitivity against specificity.It also depends on the sample size.For a typical logistic regression setting with a moderate sample size and a small to moderate effect size,either BIC,BICc or Lasso seems to be optimal.Research limitations:Numerical simulations cannot cover the whole range of data-generating processes occurring with real-world data.Thus,more simulations are needed.Practical implications:Researchers can refer to these results if they believe that their data-generating process is somewhat similar to some of the scenarios presented in this paper.Alternatively,they could run their own simulations and calculate the loss function.Originality/value:This is a systematic comparison of model choice algorithms and heuristics in context of logistic regression.The distinction between two types of sensitivity and a comparison based on a loss function are methodological novelties. 展开更多
关键词 Model choice Logistic regression Logit regression Monte Carlo simulations Sensitivity SPECIFICITY
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Discrete Choice Analysis of Temporal Factors on Social Network Growth
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作者 Kwok-Wai Cheung Yuk Tai Siu 《Intelligent Information Management》 2024年第1期21-34,共14页
Social networks like Facebook, X (Twitter), and LinkedIn provide an interaction and communication environment for users to generate and share content, allowing for the observation of social behaviours in the digital w... Social networks like Facebook, X (Twitter), and LinkedIn provide an interaction and communication environment for users to generate and share content, allowing for the observation of social behaviours in the digital world. These networks can be viewed as a collection of nodes and edges, where users and their interactions are represented as nodes and the connections between them as edges. Understanding the factors that contribute to the formation of these edges is important for studying network structure and processes. This knowledge can be applied to various areas such as identifying communities, recommending friends, and targeting online advertisements. Several factors, including node popularity and friends-of-friends relationships, influence edge formation and network growth. This research focuses on the temporal activity of nodes and its impact on edge formation. Specifically, the study examines how the minimum age of friends-of-friends edges and the average age of all edges connected to potential target nodes influence the formation of network edges. Discrete choice analysis is used to analyse the combined effect of these temporal factors and other well-known attributes like node degree (i.e., the number of connections a node has) and network distance between nodes. The findings reveal that temporal properties have a similar impact as network proximity in predicting the creation of links. By incorporating temporal features into the models, the accuracy of link prediction can be further improved. 展开更多
关键词 Discrete choice Models Temporal Factors Social Network Link Prediction Network Growth
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Type 2 Diabetes—Hard to Select a Healthy Choice
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作者 Stefan Backe 《Health》 2024年第1期1-8,共8页
Introduction: The use of foods containing high levels of sugar is increasing all the time. This is a risk factor for increased incidence of type 2 diabetes. There are few studies that have investigated the availabilit... Introduction: The use of foods containing high levels of sugar is increasing all the time. This is a risk factor for increased incidence of type 2 diabetes. There are few studies that have investigated the availability of low-sugar müsli products in grocery stores. Purpose: The study aims to identify which types of müsli contain high respectively low levels of sugar, and which brands are involved. Methods: The material consists of both qualitative interviews and observations from five grocery stores: City Gross, Hemköp, Ica Maxi, Stora Coop and Willy’s in Helsingborg, Sweden. The qualitative interviews had a semi-structured character and were recorded. The interviews took approx. 20 minutes and a textual analysis was conducted of the results. Data from observation was analyzed based on brand, nutritional composition and flavors, and also, where low sugar products were placed on store shelves. Results: The grocery stores provided together brands from AXA, Coop, Finax, Frebaco, Garant, ICA, Risenta, Saltå Kvarn och Urtekram, in total 24 müsli products. Of these products, 19 were high in sugar. The observation reveals that müsli products with high sugar content (17 - 29 g per 100 g müsli) are more prominently displayed than those with low sugar content. From the interviews with the store managers, it became clear that it would be valuable to highlight healthy müsli products on the shelves. However, central bureaucracy puts obstacles to such measures. Discussion: The study emphasizes the need for increased visibility of low-sugar products and proposes solutions such as negotiating with responsible person at the head office in Stockholm. Several reviews have shown that if the grocery store raises the prices of unhealthy food, the consumer is willing to purchase healthier müsli and other products. Conclusion: This study shows the need for grocery stores to upgrade healthy müsli products along with advertising to be able to influence customer’s shopping habits. Also, further research is needed how type 2 diabetes is affected by high intakes of food products with high sugar content. 展开更多
关键词 Type 2 Diabetes High Sugar Content in Müsli Difficulty Making Healthy choices Central Food Bureaucracy
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Oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions via Prufer transformation
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作者 LI Zhi-yu LI Kun +2 位作者 CAI Jin-ming QIN Jian-fang ZHENG Zhao-wen 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期191-200,共10页
A class of Sturm-Liouville problems with discontinuity is studied in this paper.The oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions are obtained.The main method used in ... A class of Sturm-Liouville problems with discontinuity is studied in this paper.The oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions are obtained.The main method used in this paper is based on Prufer transformation,which is different from the classical ones.Moreover,we give two examples to verify our main results. 展开更多
关键词 Sturm-Liouville problem interface condition oscillatory solution
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Role of outdoor trees on pedestrian wind and thermal conditions around a pre-education building for sustainable energy management
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作者 LI Xiao-jie TANG Hui-li 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期2039-2053,共15页
Finding sustainable energy resources is essential to face the increasing energy demand.Trees are an important part of ancient architecture but are becoming rare in urban areas.Trees can control and tune the pedestrian... Finding sustainable energy resources is essential to face the increasing energy demand.Trees are an important part of ancient architecture but are becoming rare in urban areas.Trees can control and tune the pedestrian-level wind velocity and thermal condition.In this study,a numerical investigation is employed to assess the role of trees planted in the windward direction of the building complex on the thermal and pedestrian wind velocity conditions around/inside a pre-education building located in the center of the complex.Compared to the previous studies(which considered only outside buildings),this work considers the effects of trees on microclimate change both inside/outside buildings.Effects of different parameters including the leaf area density and number of trees,number of rows,far-field velocity magnitude,and thermal condition around the main building are assessed.The results show that the flow velocity in the spacing between the first-row buildings is reduced by 30%-40% when the one-row trees with 2 m height are planted 15 m farther than the buildings.Furthermore,two rows of trees are more effective in higher velocities and reduce the maximum velocity by about 50%.The investigation shows that trees also could reduce the temperature by about 1℃around the building. 展开更多
关键词 sustainable management energy trees urban area thermal condition building
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Factors Influence Hanoians’ Choice of Non-Motorized Transport Mode to Access Bus Stations
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作者 Ngo Trung Phuong Masahiko Kikuchi +1 位作者 Aya Kojima Hisashi Kubota 《Journal of Transportation Technologies》 2024年第3期372-389,共18页
Hanoi’s rapid urbanization has led to a surge in private vehicle ownership, particularly motorcycles, amidst inadequate public transportation infrastructure. Despite government efforts, many still prefer motorized tr... Hanoi’s rapid urbanization has led to a surge in private vehicle ownership, particularly motorcycles, amidst inadequate public transportation infrastructure. Despite government efforts, many still prefer motorized transport, citing mobility and safety concerns, exacerbated by insufficient pedestrian infrastructure. This study examines the motivations behind this reliance on motorized vehicles, particularly motorcycles, in Hanoi. Findings reveal safety and convenience as primary factors driving motorized transport use, especially for accessing bus stations. Economic incentives could promote non-motorized travel and public transport adoption. Policy implications highlight the importance of addressing economic factors and improving access infrastructure to manage motorized vehicle reliance and foster sustainable urban mobility in Hanoi. 展开更多
关键词 Access Mode choice Non-Motorized Vehicles Motorized Vehicles Bus User Urban Transport Behavior
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Multi-soliton solutions of coupled Lakshmanan-Porsezian-Daniel equations with variable coefficients under nonzero boundary conditions
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作者 赵会超 马雷诺 解西阳 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期137-152,共16页
This paper aims to investigate the multi-soliton solutions of the coupled Lakshmanan–Porsezian–Daniel equations with variable coefficients under nonzero boundary conditions.These equations are utilized to model the ... This paper aims to investigate the multi-soliton solutions of the coupled Lakshmanan–Porsezian–Daniel equations with variable coefficients under nonzero boundary conditions.These equations are utilized to model the phenomenon of nonlinear waves propagating simultaneously in non-uniform optical fibers.By analyzing the Lax pair and the Riemann–Hilbert problem,we aim to provide a comprehensive understanding of the dynamics and interactions of solitons of this system.Furthermore,we study the impacts of group velocity dispersion or the fourth-order dispersion on soliton behaviors.Through appropriate parameter selections,we observe various nonlinear phenomena,including the disappearance of solitons after interaction and their transformation into breather-like solitons,as well as the propagation of breathers with variable periodicity and interactions between solitons with variable periodicities. 展开更多
关键词 soliton Riemann-Hilbert problem non-zero boundary conditions coupled Lakshmanan-Porsezian-Daniel equation
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Effects of Initial and Boundary Conditions on Heavy Rainfall Simulation over the Yellow Sea and the Korean Peninsula:Comparison of ECMWF and NCEP Analysis Data Effects and Verification with Dropsonde Observation
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作者 Jiwon HWANG Dong-Hyun CHA +2 位作者 Donghyuck YOON Tae-Young GOO Sueng-Pil JUNG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第9期1787-1803,共17页
This study evaluated the simulation performance of mesoscale convective system(MCS)-induced precipitation,focusing on three selected cases that originated from the Yellow Sea and propagated toward the Korean Peninsula... This study evaluated the simulation performance of mesoscale convective system(MCS)-induced precipitation,focusing on three selected cases that originated from the Yellow Sea and propagated toward the Korean Peninsula.The evaluation was conducted for the European Centre for Medium-Range Weather Forecasts(ECMWF)and National Centers for Environmental Prediction(NCEP)analysis data,as well as the simulation result using them as initial and lateral boundary conditions for the Weather Research and Forecasting model.Particularly,temperature and humidity profiles from 3D dropsonde observations from the National Center for Meteorological Science of the Korea Meteorological Administration served as validation data.Results showed that the ECMWF analysis consistently had smaller errors compared to the NCEP analysis,which exhibited a cold and dry bias in the lower levels below 850 hPa.The model,in terms of the precipitation simulations,particularly for high-intensity precipitation over the Yellow Sea,demonstrated higher accuracy when applying ECMWF analysis data as the initial condition.This advantage also positively influenced the simulation of rainfall events on the Korean Peninsula by reasonably inducing convective-favorable thermodynamic features(i.e.,warm and humid lower-level atmosphere)over the Yellow Sea.In conclusion,this study provides specific information about two global analysis datasets and their impacts on MCS-induced heavy rainfall simulation by employing dropsonde observation data.Furthermore,it suggests the need to enhance the initial field for MCS-induced heavy rainfall simulation and the applicability of assimilating dropsonde data for this purpose in the future. 展开更多
关键词 initial conditions dropsonde heavy rainfall forecast global model analysis evaluation
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Evaluation of Mechanical Properties and Surface Quality of Wood from Bosnia and Herzegovina Exposed to Outdoor Conditions
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作者 Redžo Hasanagić UmejrŠljivo +3 位作者 Leila Fathi Pallavi Gautam Mohsen Bahmani Miha Humar 《Journal of Renewable Materials》 EI CAS 2024年第8期1417-1431,共15页
This study investigated the mechanical properties of beech(Fagus sylvatica L.)and fir(Abies alba)wood from Bosnia and Herzegovina under outdoor exposure.Samples were exposed for 3-month exposure to assess bending stre... This study investigated the mechanical properties of beech(Fagus sylvatica L.)and fir(Abies alba)wood from Bosnia and Herzegovina under outdoor exposure.Samples were exposed for 3-month exposure to assess bending strength,color changes,and surface quality.Results showed outdoor exposure negatively affected mechanical properties,particularly in samples with extended finger joints,causing significant surface cracks in uncoated samples.Beech wood exhibited notable color changes under exposure,with approximately 50%darkening without coating compared to 25%under covered conditions.Coated samples displayed minimal color changes,affirming the efficacy of surface treatment.Fir wood exhibited a roughness of 8.264μm,while beechwood average roughness increased from 6.767 to 13.916μm after exposure,with micro-pore development affecting water performance.Microscopic analysis identified prevalent fungal colonies,including Penicillium,Aureobasidium,Sclerophoma,and Chaetomium,underscoring their role in organic matter decomposition.This study highlights the importance of wood exposure and treatment selection for various applications. 展开更多
关键词 Mechanical properties outdoor conditions cracks wood species
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Research on shell-side heat and mass transfer with multi-component in LNG spiral-wound heat exchanger under sloshing conditions
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作者 Xue-Ping Du Guang-Lei Yu +3 位作者 Ya-Cheng Xu Zhi-Jie Chen Nai-Liang Li Huan-Guang Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1333-1345,共13页
The spiral-wound heat exchanger(SWHE) is the primary low-temperature heat exchanger for large-scale LNG plants due to its high-pressure resistance, compact structure, and high heat exchange efficiency. This paper stud... The spiral-wound heat exchanger(SWHE) is the primary low-temperature heat exchanger for large-scale LNG plants due to its high-pressure resistance, compact structure, and high heat exchange efficiency. This paper studied the shell-side heat and mass transfer characteristics of vapor-liquid two-phase mixed refrigerants in an SWHE by combining a multi-component model in FLUENT software with a customized multicomponent mass transfer model. Besides, the mathematical model under the sloshing condition was obtained through mathematical derivation, and the corresponding UDF code was loaded into FLUENT as the momentum source term. The results under the sloshing conditions were compared with the relevant parameters under the steady-state condition. The shell-side heat and mass transfer characteristics of the SWHE were investigated by adjusting the component ratio and other working conditions. It was found that the sloshing conditions enhance the heat transfer performance and sometimes have insignificant effects. The sloshing condition is beneficial to reduce the flow resistance. The comprehensive performance of multi-component refrigerants has been improved and the improvement is more significant under sloshing conditions, considering both the heat transfer and pressure drop.These results will provide theoretical support for the research and design of multi-component heat and mass transfer enhancement of LNG SWHE under ocean sloshing conditions. 展开更多
关键词 Spiral-wound heat exchanger Sloshing conditions Two-phase flow MULTI-COMPONENT Heat and mass transfer
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Influence of tectonic preservation conditions on the nanopore structure of shale reservoir:A case study of Wufeng-Longmaxi Formation shale in western Hubei area,south China
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作者 Meng Xiang Shang Xu +2 位作者 Ya-Ru Wen Qi-Yang Gou Bing-Chang Liu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2203-2217,共15页
Tectonism is one of the dominant factors affecting the shale pore structure.However,the control of shale pore structure by tectonic movements is still controversial,which limits the research progress of shale gas accu... Tectonism is one of the dominant factors affecting the shale pore structure.However,the control of shale pore structure by tectonic movements is still controversial,which limits the research progress of shale gas accumulation mechanism in the complex tectonic region of southern China.In this study,34 samples were collected from two exploratory wells located in different tectonic locations.Diverse experiments,e.g.,organic geochemistry,XRD analysis,FE-SEM,low-pressure gas adsorption,and high-pressure mercury intrusion,were conducted to fully characterize the shale reservoir.The TOC,Ro,and mineral composition of the shale samples between the two wells are similar,which reflects that the shale samples of the two wells have proximate pores-generating capacity and pores-supporting capacity.However,the pore characteristics of shale samples from two wells are significantly different.Compared with the stabilized zone shale,the porosity,pore volume,and specific surface area of the deformed zone shale were reduced by 60.61%,64.85%,and 27.81%,respectively.Moreover,the macroscopic and fine pores were reduced by 54.01%and 84.95%,respectively.Fault activity and uplift denudation are not conducive to pore preservation,and the rigid basement of Huangling uplift can promote pore preservation.These three factors are important reasons for controlling the difference in pore structure between two wells shales.We established a conceptual model of shale pores evolution under different tectonic preservation conditions.This study is significant to clarify the scale of shale gas formation and enrichment in complex tectonic regions,and helps in the selection of shale sweet spots. 展开更多
关键词 Shale gas Pore structure Tectonic preservation conditions Shale gas enrichment mechanism
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Impact of wetting-drying cycles and acidic conditions on the soil aggregate stability of yellow‒brown soil
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作者 XIA Zhenyao NI Yuanzhen +2 位作者 LIU Deyu WANG Di XIAO Hai 《Journal of Mountain Science》 SCIE CSCD 2024年第6期2075-2090,共16页
Soil aggregate is the basic structural unit of soil,which is the foundation for supporting ecosystem functions,while its composition and stability is significantly affected by the external environment.This study was c... Soil aggregate is the basic structural unit of soil,which is the foundation for supporting ecosystem functions,while its composition and stability is significantly affected by the external environment.This study was conducted to explore the effect of external environment(wetting-drying cycles and acidic conditions)on the soil aggregate distribution and stability and identify the key soil physicochemical factors that affect the soil aggregate stability.The yellow‒brown soil from the Three Gorges Reservoir area(TGRA)was used,and 8 wetting-drying conditions(0,1,2,3,4,5,10 and 15 cycles)were simulated under 4 acidic conditions(pH=3,4,5 and 7).The particle size distribution and soil aggregate stability were determined by wet sieving method,the contribution of environmental factors(acid condition,wetting-drying cycle and their combined action)to the soil aggregate stability was clarified and the key soil physicochemical factors that affect the soil aggregate stability under wetting-drying cycles and acidic conditions were determined by using the Pearson’s correlation analysis,Partial least squares path modeling(PLS‒PM)and multiple linear regression analysis.The results indicate that wetting-drying cycles and acidic conditions have significant effects on the stability of soil aggregates,the soil aggregate stability gradually decreases with increasing number of wetting-drying cycles and it obviously decreases with the increase of acidity.Moreover,the combination of wetting-drying cycles and acidic conditions aggravate the reduction in the soil aggregate stability.The wetting-drying cycles,acidic conditions and their combined effect imposes significant impact on the soil aggregate stability,and the wetting-drying cycles exert the greatest influence.The soil aggregate stability is significantly correlated with the pH,Ca^(2+),Mg^(2+),maximum disintegration index(MDI)and soil bulk density(SBD).The PLS‒PM and multiple linear regression analysis further reveal that the soil aggregate stability is primarily influenced by SBD,Ca^(2+),and MDI.These results offer a scientific basis for understanding the soil aggregate breakdown mechanism and are helpful for clarifying the coupled effect of wetting-drying cycles and acid rain on terrestrial ecosystems in the TGRA. 展开更多
关键词 Yellow‒brown soil Wetting-drying cycles Acidic conditions Soil aggregate stability Soil disintegration
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Riemann–Hilbert problem for the defocusing Lakshmanan–Porsezian–Daniel equation with fully asymmetric nonzero boundary conditions
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作者 Jianying Ji Xiyang Xie 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期208-215,共8页
The Riemann–Hilbert approach is demonstrated to investigate the defocusing Lakshmanan–Porsezian–Daniel equation under fully asymmetric nonzero boundary conditions.In contrast to the symmetry case,this paper focuses... The Riemann–Hilbert approach is demonstrated to investigate the defocusing Lakshmanan–Porsezian–Daniel equation under fully asymmetric nonzero boundary conditions.In contrast to the symmetry case,this paper focuses on the branch points related to the scattering problem rather than using the Riemann surfaces.For the direct problem,we analyze the Jost solution of lax pairs and some properties of scattering matrix,including two kinds of symmetries.The inverse problem at branch points can be presented,corresponding to the associated Riemann–Hilbert.Moreover,we investigate the time evolution problem and estimate the value of solving the solutions by Jost function.For the inverse problem,we construct it as a Riemann–Hilbert problem and formulate the reconstruction formula for the defocusing Lakshmanan–Porsezian–Daniel equation.The solutions of the Riemann–Hilbert problem can be constructed by estimating the solutions.Finally,we work out the solutions under fully asymmetric nonzero boundary conditions precisely via utilizing the Sokhotski–Plemelj formula and the square of the negative column transformation with the assistance of Riemann surfaces.These results are valuable for understanding physical phenomena and developing further applications of optical problems. 展开更多
关键词 Riemann-Hilbert problem defocusing Lakshmanan-Porsezian-Daniel equation inverse scatter-ing transform asymmetric nonzero boundary conditions
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Classification research of TCM pulse conditions based on multi-label voice analysis
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作者 Haoran Shen Junjie Cao +5 位作者 Lin Zhang Jing Li Jianghong Liu Zhiyuan Chu Shifeng Wang Yanjiang Qiao 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第2期172-179,共8页
Objective:To explore the feasibility of remotely obtaining complex information on traditional Chinese medicine(TCM)pulse conditions through voice signals.Methods: We used multi-label pulse conditions as the entry poin... Objective:To explore the feasibility of remotely obtaining complex information on traditional Chinese medicine(TCM)pulse conditions through voice signals.Methods: We used multi-label pulse conditions as the entry point and modeled and analyzed TCM pulse diagnosis by combining voice analysis and machine learning.Audio features were extracted from voice recordings in the TCM pulse condition dataset.The obtained features were combined with information from tongue and facial diagnoses.A multi-label pulse condition voice classification DNN model was built using 10-fold cross-validation,and the modeling methods were validated using publicly available datasets.Results: The analysis showed that the proposed method achieved an accuracy of 92.59%on the public dataset.The accuracies of the three single-label pulse manifestation models in the test set were 94.27%,96.35%,and 95.39%.The absolute accuracy of the multi-label model was 92.74%.Conclusion: Voice data analysis may serve as a remote adjunct to the TCM diagnostic method for pulse condition assessment. 展开更多
关键词 Pulse conditions TCM pulse diagnosis Voice analysis Multi-label classification Machine learning
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Improving autoencoder-based unsupervised damage detection in uncontrolled structural health monitoring under noisy conditions
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作者 Yang Kang Wang Linyuan +4 位作者 Gao Chao Chen Mozhi Tian Zhihui Zhou Dunzhi Liu Yang 《仪器仪表学报》 EI CAS CSCD 北大核心 2024年第6期91-100,共10页
Structural health monitoring is widely utilized in outdoor environments,especially under harsh conditions,which can introduce noise into the monitoring system.Therefore,designing an effective denoising strategy to enh... Structural health monitoring is widely utilized in outdoor environments,especially under harsh conditions,which can introduce noise into the monitoring system.Therefore,designing an effective denoising strategy to enhance the performance of guided wave damage detection in noisy environments is crucial.This paper introduces a local temporal principal component analysis(PCA)reconstruction approach for denoising guided waves prior to implementing unsupervised damage detection,achieved through novel autoencoder-based reconstruction.Experimental results demonstrate that the proposed denoising method significantly enhances damage detection performance when guided waves are contaminated by noise,with SNR values ranging from 10 to-5 dB.Following the implementation of the proposed denoising approach,the AUC score can elevate from 0.65 to 0.96 when dealing with guided waves corrputed by noise at a level of-5 dB.Additionally,the paper provides guidance on selecting the appropriate number of components used in the denoising PCA reconstruction,aiding in the optimization of the damage detection in noisy conditions. 展开更多
关键词 structural health monitoring guided waves principal component analysis deep learning DENOISING dynamic environmental condition
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Impact of Initial Soil Conditions on Soil Hydrothermal and Surface Energy Fluxes in the Permafrost Region of the Tibetan Plateau
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作者 Siqiong LUO Zihang CHEN +3 位作者 Jingyuan WANG Tonghua WU Yao XIAO Yongping QIAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期717-736,共20页
Accurate initial soil conditions play a crucial role in simulating soil hydrothermal and surface energy fluxes in land surface process modeling.This study emphasized the influence of the initial soil temperature(ST)an... Accurate initial soil conditions play a crucial role in simulating soil hydrothermal and surface energy fluxes in land surface process modeling.This study emphasized the influence of the initial soil temperature(ST)and soil moisture(SM)conditions on a land surface energy and water simulation in the permafrost region in the Tibetan Plateau(TP)using the Community Land Model version 5.0(CLM5.0).The results indicate that the default initial schemes for ST and SM in CLM5.0 were simplistic,and inaccurately represented the soil characteristics of permafrost in the TP which led to underestimating ST during the freezing period while overestimating ST and underestimating SLW during the thawing period at the XDT site.Applying the long-term spin-up method to obtain initial soil conditions has only led to limited improvement in simulating soil hydrothermal and surface energy fluxes.The modified initial soil schemes proposed in this study comprehensively incorporate the characteristics of permafrost,which coexists with soil liquid water(SLW),and soil ice(SI)when the ST is below freezing temperature,effectively enhancing the accuracy of the simulated soil hydrothermal and surface energy fluxes.Consequently,the modified initial soil schemes greatly improved upon the results achieved through the long-term spin-up method.Three modified initial soil schemes experiments resulted in a 64%,88%,and 77%reduction in the average mean bias error(MBE)of ST,and a 13%,21%,and 19%reduction in the average root-mean-square error(RMSE)of SLW compared to the default simulation results.Also,the average MBE of net radiation was reduced by 7%,22%,and 21%. 展开更多
关键词 initial soil conditions soil temperature soil liquid water soil ice surface energy fluxes PERMAFROST
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