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Valuations on Concave Functions and Log-Concave Functions
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作者 LIU Lijuan 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2019年第6期479-484,共6页
Recently, the theory of valuations on function spaces has been rapidly growing. It is more general than the classical theory of valuations on convex bodies. In this paper, all continuous, SL(n) and translation invaria... Recently, the theory of valuations on function spaces has been rapidly growing. It is more general than the classical theory of valuations on convex bodies. In this paper, all continuous, SL(n) and translation invariant valuations on concave functions and log-concave functions are completely classified, respectively. 展开更多
关键词 valuations CONCAVE FUNCTIONS LOG-CONCAVE FUNCTIONS CHARACTERIZATION THEOREM
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Financial Statement Valuations in Italian Accounting Thought Between the 19th and the 20th Century: From "Exchange Value" to "Historical Cost"
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作者 Enrico Gonnella 《Journal of Modern Accounting and Auditing》 2012年第9期1255-1271,共17页
The main subject of this paper is the theory of financial statement valuations observed in its historical development. More notably, regarding the subject, the research is concerned with some theoretical concepts deve... The main subject of this paper is the theory of financial statement valuations observed in its historical development. More notably, regarding the subject, the research is concerned with some theoretical concepts developed by the Italian doctrine in a very specific age, namely, between the 19th and the 20th century, which in fact, devoid of any accounting regulation. This paper analyzes in particular the shift from the exchange value rule to the historical cost method and tries to explain the reasons of such a development. In the second half of the 19th century, some of the best Italian scholars, who were faced with the need to properly develop the problem of accounting valuations, thought that it was appropriate to rely on concepts that belonged to similar sciences, such as economics and real estate appraisal, by blindly borrowing the theory of value from the former and the theory of valuations from the latter. During that age, everything hinged around the concept of exchange value. At the dawn of the 20th century, the Italian accounting doctrine began to wonder about a subject that was crucial to the financial statement theory: the informative purposes underlying the financial statements. At the same time, the first principle took shape, which might be called as the "finalistic principle of value". It is still the basis of the theory of financial accounting measurements, for which different evaluative criteria must be applied to different informative purposes. Thus, an alternative criterion to that of the exchange value makes its appearance on the scene of the accounting valuations, notably the historical cost. The introduction of the historical cost criteria and above all the relinquishment of the combination of the "economic cost" in favor of that of the "manufacturing cost" allow the Italian accounting to get rid of the theories of economics and real estate appraisal, thus, becoming independent regarding the financial statement valuations. 展开更多
关键词 accounting history financial statement valuations asset valuation exchange value historical cost ITALY
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Implicative Pseudo Valuations on Hoops 被引量:1
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作者 WANG Mei XIN Xiao-long WANG Jun-tao 《Chinese Quarterly Journal of Mathematics》 2018年第1期51-60,共10页
The concept of implicative pseudo valuations on hoops is introduced and some related properties are investigated. As an application of properties of pseudo valuations, we find the relationship between a pseudo valuati... The concept of implicative pseudo valuations on hoops is introduced and some related properties are investigated. As an application of properties of pseudo valuations, we find the relationship between a pseudo valuation and an implicative pseudo valuation and obtain some characterizations of implicative pseudo valuations. In particular, we show that a pseudo valuation on regular hoops is implicative if and only if it satisfies φ(x■x') = 0.This result will provide a more general algebraic foundation for pseudo valuations theory on algebraic structures based on substructure logic. 展开更多
关键词 (implicative) pseudo valuation HOOPS
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Complex-Valued Valuations on L^(p) Spaces
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作者 LIU Lijuan 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2022年第1期35-41,共7页
All continuous translation invariant complex-valued valuations on Lebesgue measurable functions are completely classified.And all continuous rotation invariant complex-valued valuations on spherical Lebesgue measurabl... All continuous translation invariant complex-valued valuations on Lebesgue measurable functions are completely classified.And all continuous rotation invariant complex-valued valuations on spherical Lebesgue measurable functions are also completely classified. 展开更多
关键词 convex body VALUATION translation invariance rotation invariance
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基于承包商支付意愿的工程渣土资源化利用激励机制研究——以长沙市为例
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作者 易欣 刘沫村 +2 位作者 陆佳惠 沈良峰 邱慧 《中国环境科学》 北大核心 2025年第4期2323-2332,共10页
出于成本考虑,目前承包商工程渣土多采取填埋、倾倒处置方式,如何激励其转向资源化利用是个难题.不同于以往定性研究,基于混合式条件价值评估新方法,以湖南省长沙市585位建筑从业人员的调查数据为样本,通过对承包商支付意愿及影响因素... 出于成本考虑,目前承包商工程渣土多采取填埋、倾倒处置方式,如何激励其转向资源化利用是个难题.不同于以往定性研究,基于混合式条件价值评估新方法,以湖南省长沙市585位建筑从业人员的调查数据为样本,通过对承包商支付意愿及影响因素进行研究,将不明晰的非资源化处置收费价格明确化,然后提出了相应的激励机制.结果表明:承包商的平均支付意愿为73.69元/t,高于目前渣土填埋平均费用20元/t,以及非法倾倒的处罚期望成本16.70~25元/t,建议政府通过调价和征收处置税使渣土消纳费超过73.69元/t,将非法倾倒处罚额从5000元/台提高到15000元/台;工程资源化利用平均处置成本137元/t,再产品平均售价40元/t,加上承包商平均支付意愿仍小于成本.政府可根据差额直接补贴或奖励新技术研发以降低成本,并出台规定扩大再产品用量,通过需求提高再产品市场价格.74.35%受访者愿意支付以支持工程渣土资源化利用,承包商的企业性质、社会压力、环境认知、当前满意度等因素正向影响其支付意愿,受访者的项目经验却对支付意愿负向影响.政府通过加大工程渣土资源化利用宣传的引导规制,提升资源化利用补贴和非法倾倒处罚力度的奖惩规制,也都能有效激励承包商采取资源化利用. 展开更多
关键词 工程渣土资源化利用 承包商支付意愿 支付意愿影响因素 hybrid contingent valuation method
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Impact of land use change on carbon storage in the middle reaches of the Yellow River,China 被引量:1
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作者 SHI Xiaoliang ZHANG Jie +4 位作者 LIU Simin DING Hao CHEN Xi WANG Li ZHANG Dan 《Journal of Arid Land》 2025年第2期167-181,共15页
The implementation of long-term shelterbelt programs in the middle reaches of the Yellow River(MRYR),China not only has improved the overall ecological environment,but also has led to the changes of land use pattern,c... The implementation of long-term shelterbelt programs in the middle reaches of the Yellow River(MRYR),China not only has improved the overall ecological environment,but also has led to the changes of land use pattern,causing carbon storage exchanges.However,the relationship between carbon storage and land use change in the MRYR is not concerned,which results in the uncertainty in the simulation of carbon storage in this area.Land use changes directly affect the carbon storage capacity of ecosystems,and as an indicator reflecting the overall state of land use,land use degree has an important relationship with carbon storage.In this study,land use data and the integrated valuation of ecosystem services and trade-offs(InVEST)model were used to assess the trends in land use degree and carbon storage in the MRYR during 1980-2020.The potential impact index and the standard deviation ellipse(SDE)algorithm were applied to quantify and analyze the characteristics of the impact of land use changes on carbon storage.Subsequently,land use transitions that led to carbon storage variations and their spatial variations were determined.The results showed that:(1)the most significant periods of carbon storage changes and land use transitions were observed during 1990-1995 and 1995-2020,with the most changed areas locating in the east of Fenhe River and in northwestern Henan Province;(2)the positive impact of land use degree on carbon storage may be related to the environmental protection measures implemented along the Yellow River,while the negative impact may be associated with the expansion of construction land in plain areas;and(3)the conversion of other land use types to grassland was the primary factor affecting carbon storage changes during 1980-2020.In future land use planning,attention should be given to the direction of grassland conversion,and focus on reasonably limiting the development of construction land.To enhance carbon storage,it will be crucial to increase the area of high-carbon-density land types,such as forest land and grassland under the condition that the area of permanent farmland does not decrease. 展开更多
关键词 carbon storage land use degree integrated valuation of ecosystem services and trade-offs(InVEST)model potential impact standard deviation ellipse(SDE)
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Care for the soul of science:Equity and virtue in reform and reformation
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作者 Mare Knibbe Sarah de Rijcke Bart Penders 《Cultures of Science》 2025年第1期12-23,共12页
Scientific reforms proposed in response to moral concerns about corrupted science are reminiscent of the Christian Reformation,which similarly formed a moral reorientation as a reaction to malpractices.In this study,w... Scientific reforms proposed in response to moral concerns about corrupted science are reminiscent of the Christian Reformation,which similarly formed a moral reorientation as a reaction to malpractices.In this study,we compare these moral reorientation processes to contextualize two different moral programmes of the scientific reform movement and their sociopolitical conditions.We argue that such an explication of moral programmes is vital to build legitimacy and reflect on value-prioritization.While epistemic programmes are foregrounded,moral programmes also play a crucial role in shaping science,and different moral programmes offer different promises for the sustained support of credible,reliable,fair and equitable science.We discuss the virtue and equity programmes,and through interrogating both programmes in relation to the Reformation,we display the relevance of sociopolitical contexts to how key values operate in science and generate orders of worth.These insights aim to stimulate debate about the conditions for opting for either of these moral programmes.In our view,not all moral programmes offer equal promise for the sustained support of credible,equitable and fair science. 展开更多
关键词 Scientific reform REFORMATION moral programme valuation VIRTUE EQUITY
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A Study on the Risks Associated with On-Balance Sheet Recognition of Data Resources
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作者 Xia Xiao 《Proceedings of Business and Economic Studies》 2025年第5期169-176,共8页
This study focuses on the risks associated with the on-balance sheet recognition of data resources.At the legal level,disputes over ownership often arise due to unclear data property rights,while privacy protection,cy... This study focuses on the risks associated with the on-balance sheet recognition of data resources.At the legal level,disputes over ownership often arise due to unclear data property rights,while privacy protection,cybersecurity,and cross-border data flows create additional compliance challenges.In terms of recognition,the subjectivity of traditional valuation methods,the lack of active markets,and the rapid depreciation of data value caused by technological iteration hinder reliable measurement.With respect to disclosure,organizations face a dilemma between transparency and confidentiality.Collectively,these issues exacerbate audit risks.It is therefore imperative to establish an appropriate legal,accounting,and auditing framework to mitigate such risks and remove barriers to the proper recognition of data assets on balance sheets. 展开更多
关键词 Data resources On-balance sheet recognition Valuation uncertainty Information disclosure RISK
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Assessing the Economic Value of Improvement in Water Quality and Aquatic Ecosystem Services Resulting from Ecological Stream Restoration in South Korea
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作者 Hyun No Kim Hwanhee Ryu 《Journal of Environmental & Earth Sciences》 2025年第1期471-484,共14页
Urbanization and environmental degradation have led to significant declines in water quality and aquatic ecosystem health,highlighting the urgent need for effective restoration efforts.This study applies an integrated... Urbanization and environmental degradation have led to significant declines in water quality and aquatic ecosystem health,highlighting the urgent need for effective restoration efforts.This study applies an integrated analysis approach to estimate the economic value and benefits of improvements in water quality and aquatic ecosystem services resulting from the Ecological Stream Restoration Project.Using survey data analyzed through the choice experiment(CE)method,we assessed respondents’preferences for various ecosystem services,including water-friendly services,ecological functions,water-level control,and water-quality purification.Three empirical analysis models—the Conditional Logit Model(CLM),Nested Logit Model(NL),and Error Component Logit Model(ECL)—were applied,with the ECL model identified as the most suitable for this study.From the physical impact assessment,we derived compensating variations to estimate the annual economic benefits of the project.The estimated annual economic value of water quality improvement due to the Anyangcheon Ecological Stream Restoration Project ranged from approximately KRW 10.54 billion to KRW 21.44 billion,while the economic value of aquatic ecosystem improvement was estimated to range from KRW 6.05 billion to KRW 12.30 billion annually.This study provides analytic framework that can inform future ecological restoration projects and sustainable water management policies. 展开更多
关键词 Ecological Stream Restoration Non-Market Valuation Choice Experiment Ecosystem Services Integrated Environmental And Economic Analysis
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Assessing Ecological Impacts of Urban Land Valuation:AI and Regression Models for Sustainable Land Management
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作者 Yana Volkova Elena Bykowa +9 位作者 Oksana Pirogova Sergey Barykin Dmitriy Rodionov Ilya Sonts Angela Mottaeva Alexey Mikhaylov Dmitry Morkovkin N.B.A.Yousif Tomonobu Senjyu Farooq Ahmed Shah 《Research in Ecology》 2025年第2期192-208,共17页
The results of mass appraisal in many countries are used as a basis for calculating the amount of real estate tax,therefore,regardless of the methods used to calculate it,the resulting value should be as close as poss... The results of mass appraisal in many countries are used as a basis for calculating the amount of real estate tax,therefore,regardless of the methods used to calculate it,the resulting value should be as close as possible to the market value of the real estate to maintain a balance of interests between the state and the rights holders.In practice,this condition is not always met,since,firstly,the quality of market data is often very low,and secondly,some markets are characterized by low activity,which is expressed in a deficit of information on asking prices.The aim of the work is ecological valuation of land use:how regression-based mass appraisal can inform ecological conservation,land degradation,and sustainable land management.Four multiple regression models were constructed for AI generated map of land plots for recreational use in St.Petersburg(Russia)with different volumes of market information(32,30,20 and 15 units of market information with four price-forming factors).During the analysis of the quality of the models,it was revealed that the best result is shown by the model built on the maximum sample size,then the model based on 15 analogs,which proves that a larger number of analog objects does not always allow us to achieve better results,since the more analog objects there are. 展开更多
关键词 Land Use Sustainability Ecological Valuation Regression Modeling AI in Ecology Landscape Conservation
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Integrating Environmental Value into Strategic Environmental Assessment:An Empirical Application to a Multipurpose Rural Water Development Project in South Korea
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作者 Hyun No Kim Hwanhee Ryu 《Journal of Environmental & Earth Sciences》 2025年第7期285-298,共14页
This study examines the empirical feasibility of quantitatively integrating environmental value information into Strategic Environmental Assessment(SEA).An analytical framework was established to incorporate environme... This study examines the empirical feasibility of quantitatively integrating environmental value information into Strategic Environmental Assessment(SEA).An analytical framework was established to incorporate environmental cost estimates into the SEA process by utilizing ecosystem service unit values provided by the Environmental Valuation Information System(EVIS),a national platform developed to support the evaluation of policies and projects.The framework was applied to a case study involving a multipurpose rural water development project in South Korea.Ecosystem service losses resulting from the project were quantified using biophysical indicators,such as vegetation biomass,forest area,and hydrological functions,and subsequently monetized through the application of the market price method,replacement cost method,and contingent valuation method.The total annual environmental cost was estimated to be approximately KRW 56.18 billion,with the majority attributable to losses in forest conservation and climate regulation services.These findings demonstrate that quantified environmental data can serve as a robust basis for alternative comparison and site evaluation within SEA.The study provides empirical evidence supporting the advancement of SEA from a predominantly procedural tool focused on environmental protection to a more comprehensive sustainability assessment framework that integrates environmental,economic,and social considerations.Furthermore,the results suggest that EVIS-based quantitative information holds potential for broader application in other national evaluation systems,such as preliminary feasibility studies and regulatory impact assessments. 展开更多
关键词 Environmental Valuation Information System(EVIS) Strategic Environmental Assessment(SEA) Sustainability Assessment Ecosystem Services Environmental Decision-Making
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Impact of climate change and land use/cover change on water yield in the Liaohe River Basin,Northeast China
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作者 LYU Leting JIANG Ruifeng +1 位作者 ZHENG Defeng LIANG Liheng 《Journal of Arid Land》 2025年第2期182-199,共18页
The Liaohe River Basin(LRB)in Northeast China,a critical agricultural and industrial zone,has faced escalating water resource pressures in recent decades due to rapid urbanization,intensified land use changes,and clim... The Liaohe River Basin(LRB)in Northeast China,a critical agricultural and industrial zone,has faced escalating water resource pressures in recent decades due to rapid urbanization,intensified land use changes,and climate variability.Understanding the spatiotemporal dynamics of water yield and its driving factors is essential for sustainable water resource management in this ecologically sensitive region.This study employed the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model to quantify the spatiotemporal patterns of water yield in the LRB(dividing into six sub-basins from east to west:East Liaohe River Basin(ELRB),Taizi River Basin(TRB),Middle Liaohe River Basin(MLRB),West Liaohe River Basin(WLRB),Xinkai River Basin(XRB),and Wulijimuren River Basin(WRB))from 1993 to 2022,with a focus on the impacts of climate change and land use cover change(LUCC).Results revealed that the LRB had an average annual precipitation of 483.15 mm,with an average annual water yield of 247.54 mm,both showing significant upward trend over the 30-a period.Spatially,water yield demonstrated significant heterogeneity,with higher values in southeastern sub-basins and lower values in northwestern sub-basins.The TRB exhibited the highest water yield due to abundant precipitation and favorable topography,while the WRB recorded the lowest water yield owing to arid conditions and sparse vegetation.Precipitation played a significant role in shaping the annual fluctuations and total volume of water yield,with its variability exerting substantially greater impacts than actual evapotranspiration(AET)and LUCC.However,LUCC,particularly cultivated land expansion and grassland reduction,significantly reshaped the spatial distribution of water yield by modifying surface runoff and infiltration patterns.This study provides critical insights into the spatiotemporal dynamics of water yield in the LRB,emphasizing the synergistic effects of climate change and land use change,which are pivotal for optimizing water resource management and advancing regional ecological conservation. 展开更多
关键词 Liaohe River Basin water yield Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model climate change land use cover change(LUCC)
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Evolution and Driving Factors of Water Conservation Function in the Three Gorges Reservoir Area, China
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作者 LIU Lu WANG Dongsheng +2 位作者 LIU Qianxi ERINA Oxana ZHANG Conglin 《Chinese Geographical Science》 2025年第3期600-611,共12页
The Three Gorges Project,the largest water conservation initiative globally,is located within the Three Gorges Reservoir Area(TGRA),a critical zone for water conservation and ecological protection.There is an urgent n... The Three Gorges Project,the largest water conservation initiative globally,is located within the Three Gorges Reservoir Area(TGRA),a critical zone for water conservation and ecological protection.There is an urgent need to better understand and protect the evolving water conservation functions of the TGRA,alongside identifying the driving mechanisms within its ecological barrier re-gion.This paper explores the spatial and temporal evolution of water conservation function in the TGRA from 1990 to 2020 and its fu-ture trends under different development scenarios from 2020 to 2030.Key driving factors influencing the water conservation function are identified,and a comprehensive development scenario is proposed.The findings indicate a general upward trend in the water conser-vation function of the TGRA,characterized by an initial increase,a subsequent decline,and a final recovery.Moreover,land use changes are found to be the primary factor driving these variations,followed by climatic factors such as precipitation.Under various de-velopment scenarios,the prioritization of water conservation outcomes is ranked as follows:ecological protection>cropland protec-tion>natural development>urban development.The results of this study offer valuable insights for balancing economic development with ecological preservation. 展开更多
关键词 water conservation environmental impact Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model scenario simulation land use change sustainable development Three Gorges Reservoir Area(TGRA) China
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Impacts of land use and cover change on carbon storage:Multi-scenario projections in the arid region of Northwest China
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作者 FENG Xuyu ZHAO Xiao +3 位作者 TONG Ling WANG Sufen DING Risheng KANG Shaozhong 《Regional Sustainability》 2025年第4期96-118,共23页
Carbon storage serves as a key indicator of ecosystem services and plays a vital role in maintaining the global carbon balance.Land use and cover change(LUCC)is one of the primary drivers influencing carbon storage va... Carbon storage serves as a key indicator of ecosystem services and plays a vital role in maintaining the global carbon balance.Land use and cover change(LUCC)is one of the primary drivers influencing carbon storage variations in terrestrial ecosystems.Therefore,evaluating the impacts of LUCC on carbon storage is crucial for achieving strategic goals such as the China’s dual carbon goals(including carbon peaking and carbon neutrality).This study focuses on the Aral Irrigation Area in Xinjiang Uygur Autonomous Region,China,to assess the impacts of LUCC on regional carbon storage and their spatiotemporal dynamics.A comprehensive LUCC database from 2000 to 2020 was developed using Landsat satellite imagery and the random forest classification algorithm.The integrated valuation of ecosystem services and trade-offs(InVEST)model was applied to quantify carbon storage and analyze its response to LUCC.Additionally,future LUCC patterns for 2030 were projected under multiple development scenarios using the patch-generating land use simulation(PLUS)model.These future LUCC scenarios were integrated with the InVEST model to simulate carbon storage trends under different land management pathways.Between 2000 and 2020,the dominant land use types in the study area were cropland(area proportion of 35.52%),unused land(34.80%),and orchard land(12.19%).The conversion of unused land and orchard land significantly expanded the area of cropland,which increased by 115,742.55 hm^(2).During this period,total carbon storage and carbon density increased by 7.87×10^(6) Mg C and 20.19 Mg C/hm^(2),respectively.The primary driver of this increase was the conversion of unused land into cropland,accounting for 49.28%of the total carbon storage gain.Carbon storage was notably lower along the northeastern and southeastern edges.By 2030,the projected carbon storage is expected to increase by 0.99×10^(6),1.55×10^(6),and 1.71×10^(6) Mg C under the natural development,cropland protection,and ecological conservation scenarios,respectively.In contrast,under the urban development scenario,carbon storage is projected to decline by 0.40×10^(6) Mg C.In line with China’s dual carbon goals,the ecological conservation scenario emerges as the most effective strategy for enhancing carbon storage.Accordingly,strict enforcement of the cropland red line is recommended.This study provides a valuable scientific foundation for regional ecosystem restoration and sustainable development in arid regions. 展开更多
关键词 Land use and cover change(LUCC) Carbon storage Carbon density Ecological conservation Integrated valuation of ecosystem services and trade-offs(InVEST)model Patch-generating land use simulation(PLUS)model
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Real-valued valuations on Sobolev spaces 被引量:2
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作者 MA Dan 《Science China Mathematics》 SCIE CSCD 2016年第5期921-934,共14页
Continuous, SL(n) and translation invariant real-valued valuations on Sobolev spaces are classified.The centro-affine Hadwiger's theorem is applied. In the homogeneous case, these valuations turn out to be L^p-nor... Continuous, SL(n) and translation invariant real-valued valuations on Sobolev spaces are classified.The centro-affine Hadwiger's theorem is applied. In the homogeneous case, these valuations turn out to be L^p-norms raised to p-th power(up to suitable multipication scales). 展开更多
关键词 Sobolev space valuation convex polytope
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Blowing-ups and Valuations on Surfaces
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作者 Ning XU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2011年第7期1305-1314,共10页
In this paper, we show that all the nontrivial valuations on surfaces can be given by the infinite sequences of blowing-ups, and give the process of blowing-ups.
关键词 VALUATION HEIGHT RANK totally ordered group blowing-ups
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Valuations on arithmetic surfaces
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作者 XU Ning Department of Mathematics, Graduate School of Chinese Academy of Sciences, Beijing 100049, China 《Science China Mathematics》 SCIE 2009年第1期66-76,共11页
In this paper, we give the definition of the height of a valuation and the definition of the big field ? p,G , where p is a prime and G ? ? is an additive subgroup containing 1. We conclude that ? p,G is a field and ?... In this paper, we give the definition of the height of a valuation and the definition of the big field ? p,G , where p is a prime and G ? ? is an additive subgroup containing 1. We conclude that ? p,G is a field and ? p,G is algebraically closed. Based on this the author obtains the complete classification of valuations on arithmetic surfaces. Furthermore, for any m ? p,G n ∈ ?, let V m,n be an ∝-vector space of dimension n - m + 1, whose coordinates are indexed from m to n. We generalize the definition of ? p,G , where p is a prime and G ? V m,n is an additive subgroup containing 1. We also conclude that ? p,G is a field if m ? 0 ? n. 展开更多
关键词 VALUATION HEIGHT RANK totally ordered group big field transcendental number 14J10
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Generalized valuations on MTL-algebras
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作者 Juntao WANG Pengfei HE 《Frontiers of Mathematics in China》 SCIE CSCD 2022年第4期521-543,共23页
In this paper,we study some kinds of generalized valuations on MTL-algebras,discuss the relationship between the cokernel of generalized valuations and types of filters on MTL-algebras.Then,we give some equivalent cha... In this paper,we study some kinds of generalized valuations on MTL-algebras,discuss the relationship between the cokernel of generalized valuations and types of filters on MTL-algebras.Then,we give some equivalent characterizations of positive implicative generalized valuations on MTL-algebras.Finally,we characterize the structure theory of quotient MTL algebras based on the congruence relation,which is constructed by generalized valuations.The results of this paper not only generalize related theories of generalized valuations,but also enrich the algebraic conclusion of probability measure,on algebras of triangular norm based fuzzy logic. 展开更多
关键词 Fuzzy logic MTL-algebra generalized valuation filter
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Stability of Valuations: Higher Rational Rank
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作者 Chi Li Chenyang Xu 《Peking Mathematical Journal》 2018年第1期1-79,共79页
Given a klt singularity x∈(X,D),we show that a quasi-monomial valuation v with a finitely generated associated graded ring is a minimizer of the normalized vol-ume functionvol_((X,D),x),if and only if v induces a de... Given a klt singularity x∈(X,D),we show that a quasi-monomial valuation v with a finitely generated associated graded ring is a minimizer of the normalized vol-ume functionvol_((X,D),x),if and only if v induces a degeneration to a K-semistable log Fano cone singularity.Moreover,such a minimizer is unique among all quasi-mono-mial valuations up to rescaling.As a consequence,we prove that for a klt singular-ity x∈X on the Gromov-Hausdorff limit of Kähler-Einstein Fano manifolds,the intermediate K-semistable cone associated with its metric tangent cone is uniquely determined by the algebraic structure of x∈X,hence confirming a conjecture by Donaldson-Sun. 展开更多
关键词 Quasi-monomial valuation Normalized volume K-stability Metric tangent cone
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Influence of Human Activity Intensity on Habitat Quality in Hainan Tropical Rainforest National Park,China 被引量:5
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作者 HAN Nianlong YU Miao +2 位作者 JIA Peihong ZHANG Yucheng HU Ke 《Chinese Geographical Science》 SCIE CSCD 2024年第3期519-532,共14页
Due to long-term human activity interference,the Hainan Tropical Rainforest National Park(HTRNP)of China has experienced ecological problems such as habitat fragmentation and biodiversity loss,and with the expanding s... Due to long-term human activity interference,the Hainan Tropical Rainforest National Park(HTRNP)of China has experienced ecological problems such as habitat fragmentation and biodiversity loss,and with the expanding scope and intensity of human activity impact,the regional ecological security is facing serious challenges.A scientific assessment of the interrelationship between human activity intensity and habitat quality in the HTRNP is a prerequisite for achieving effective management of ecological disturbances caused by human activities and can also provide scientific strategies for the sustainable development of the region.Based on the land use change data in 2000,2010,and 2020,the spatial and temporal variations and the relationship between habitat quality(HQ)and human activity intensity(HAI)in the HTRNP were explored using the integrated valuation of ecosystem services and trade-offs(InVEST)model.System dynamics and land use simulation models were also combined to conduct multi-scenario simulations of their relationships.The results showed that during 2000–2020,the habitat quality of the HTRNP improved,the intensity of human activities decreased each year,and there was a negative correlation between the two.Second,the system dynamic model could be well coupled with the land use simulation model by combining socio-economic and natural factors.The simulation scenarios of the coupling model showed that the harmonious development(HD)scenario is effective in curbing the increasing trend of human activity intensity and decreasing trend of habitat quality,with a weaker trade-off between the two compared with the baseline development(BD)and investment priority oriented(IPO)scenarios.To maintain the authenticity and integrity of the HTRNP,effective measures such as ecological corridor construction,ecological restoration,and the implementation of ecological compensation policies need to be strengthened. 展开更多
关键词 human activity intensity(HAI) habitat quality(HQ) bivariate spatial autocorrelation system dynamics model integrated valuation of ecosystem services and trade-offs(InVEST)model Hainan Tropical Rainforest National Park(HTRNP)of China
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