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LociScan,a tool for screening genetic marker combinations for plant variety discrimination
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作者 Yang Yang Hongli Tian +5 位作者 Hongmei Yi Zi Shi Lu Wang Yaming Fan Fengge Wang Jiuran Zhao 《The Crop Journal》 SCIE CSCD 2024年第2期583-593,共11页
To reduce the cost and increase the efficiency of plant genetic marker fingerprinting for variety discrimination,it is desirable to identify the optimal marker combinations.We describe a marker combination screening m... To reduce the cost and increase the efficiency of plant genetic marker fingerprinting for variety discrimination,it is desirable to identify the optimal marker combinations.We describe a marker combination screening model based on the genetic algorithm(GA)and implemented in a software tool,Loci Scan.Ratio-based variety discrimination power provided the largest optimization space among multiple fitness functions.Among GA parameters,an increase in population size and generation number enlarged optimization depth but also calculation workload.Exhaustive algorithm afforded the same optimization depth as GA but vastly increased calculation time.In comparison with two other software tools,Loci Scan accommodated missing data,reduced calculation time,and offered more fitness functions.In large datasets,the sample size of training data exerted the strongest influence on calculation time,whereas the marker size of training data showed no effect,and target marker number had limited effect on analysis speed. 展开更多
关键词 Plant variety discrimination Genetic marker combination Variety discrimination power Genetic algorithm
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Discrimination of polysorbate 20 by high-performance liquid chromatography-charged aerosol detection and characterization for components by expanding compound database and library
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作者 Shi-Qi Wang Xun Zhao +10 位作者 Li-Jun Zhang Yue-Mei Zhao Lei Chen Jin-Lin Zhang Bao-Cheng Wang Sheng Tang Tom Yuan Yaozuo Yuan Mei Zhang Hian Kee Lee Hai-Wei Shi 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第5期722-732,共11页
Analyzing polysorbate 20(PS20)composition and the impact of each component on stability and safety is crucial due to formulation variations and individual tolerance.The similar structures and polarities of PS20 compon... Analyzing polysorbate 20(PS20)composition and the impact of each component on stability and safety is crucial due to formulation variations and individual tolerance.The similar structures and polarities of PS20 components make accurate separation,identification,and quantification challenging.In this work,a high-resolution quantitative method was developed using single-dimensional high-performance liquid chromatography(HPLC)with charged aerosol detection(CAD)to separate 18 key components with multiple esters.The separated components were characterized by ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UHPLC-Q-TOF-MS)with an identical gradient as the HPLC-CAD analysis.The polysorbate compound database and library were expanded over 7-time compared to the commercial database.The method investigated differences in PS20 samples from various origins and grades for different dosage forms to evaluate the composition-process relationship.UHPLC-Q-TOF-MS identified 1329 to 1511 compounds in 4 batches of PS20 from different sources.The method observed the impact of 4 degradation conditions on peak components,identifying stable components and their tendencies to change.HPLC-CAD and UHPLC-Q-TOF-MS results provided insights into fingerprint differences,distinguishing quasi products. 展开更多
关键词 Polysorbate 20 Component DATABASE discrimination Degradation
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The Analysis of the Correlation between SPT and CPT Based on CNN-GA and Liquefaction Discrimination Research
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作者 Ruihan Bai Feng Shen +2 位作者 Zihao Zhao Zhiping Zhang Qisi Yu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1159-1182,共24页
The objective of this study is to investigate themethods for soil liquefaction discrimination. Typically, predicting soilliquefaction potential involves conducting the standard penetration test (SPT), which requires f... The objective of this study is to investigate themethods for soil liquefaction discrimination. Typically, predicting soilliquefaction potential involves conducting the standard penetration test (SPT), which requires field testing and canbe time-consuming and labor-intensive. In contrast, the cone penetration test (CPT) provides a more convenientmethod and offers detailed and continuous information about soil layers. In this study, the feature matrix based onCPT data is proposed to predict the standard penetration test blow count N. The featurematrix comprises the CPTcharacteristic parameters at specific depths, such as tip resistance qc, sleeve resistance f s, and depth H. To fuse thefeatures on the matrix, the convolutional neural network (CNN) is employed for feature extraction. Additionally,Genetic Algorithm (GA) is utilized to obtain the best combination of convolutional kernels and the number ofneurons. The study evaluated the robustness of the proposed model using multiple engineering field data sets.Results demonstrated that the proposed model outperformed conventional methods in predicting N values forvarious soil categories, including sandy silt, silty sand, and clayey silt. Finally, the proposed model was employedfor liquefaction discrimination. The liquefaction discrimination based on the predicted N values was comparedwith the measured N values, and the results showed that the discrimination results were in 75% agreement. Thestudy has important practical application value for foundation liquefaction engineering. Also, the novel methodadopted in this research provides new ideas and methods for research in related fields, which is of great academicsignificance. 展开更多
关键词 CNN liquefaction discrimination SPT CPT
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Skmer approach improves species discrimination in taxonomically problematic genus Schima(Theaceae)
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作者 Han-Ning Duan Yin-Zi Jiang +4 位作者 Jun-Bo Yang Jie Cai Jian-Li Zhao Lu Li Xiang-Qin Yu 《Plant Diversity》 SCIE CAS CSCD 2024年第6期713-722,共10页
Genome skimming has dramatically extended DNA barcoding from short DNA fragments to next generation barcodes in plants.However,conserved DNA barcoding markers,including complete plastid genome and nuclear ribosomal DN... Genome skimming has dramatically extended DNA barcoding from short DNA fragments to next generation barcodes in plants.However,conserved DNA barcoding markers,including complete plastid genome and nuclear ribosomal DNA(nrDNA)sequences,are inadequate for accurate species identification.Skmer,a recently proposed approach that estimates genetic distances among species based on unassembled genome skims,has been proposed to effectively improve species discrimination rate.In this study,we used Skmer to identify species based on genomic skims of 47 individuals representing 10 out of 13 species of Schima(Theaceae)from China.The unassembled reads identified six species,with a species identification rate of 60%,twice as high as previous efforts that used plastid genomes(27.27%).In addition,Skmer was able to identify Schima species with only 0.5sequencing depth,as six species were well-supported with unassembled data sizes as small as 0.5 Gb.These findings demonstrate the potential for Skmer approach in species identification,where nuclear genomic data plays a crucial role.For taxonomically difficult taxa such as Schima,which have diverged recently and have low levels of genetic variation,Skmer is a promising alternative to next generation barcodes. 展开更多
关键词 SCHIMA Genome skimming Species discrimination Skmer
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Balancing the minimum error rate and minimum copy consumption in quantum state discrimination
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作者 Boxuan Tian Zhibo Hou +2 位作者 Guo-Yong Xiang Chuan-Feng Li Guang-Can Guo 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第7期40-42,39,I0002,I0003,共6页
Extracting more information and saving quantum resources are two main aims for quantum measurements.However,the optimization of strategies for these two objectives varies when discriminating between quantum states |ψ... Extracting more information and saving quantum resources are two main aims for quantum measurements.However,the optimization of strategies for these two objectives varies when discriminating between quantum states |ψ_(0)> and |ψ_(1)> through multiple measurements.In this study,we introduce a novel state discrimination model that reveals the intricate relationship between the average error rate and average copy consumption.By integrating these two crucial metrics and minimizing their weighted sum for any given weight value,our research underscores the infeasibility of simultaneously minimizing these metrics through local measurements with one-way communication.Our findings present a compelling trade-off curve,highlighting the advantages of achieving a balance between error rate and copy consumption in quantum discrimination tasks,offering valuable insights into the optimization of quantum resources while ensuring the accuracy of quantum state discrimination. 展开更多
关键词 quantum measurement quantum control quantum state discrimination
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FPGA implementation of 500-MHz high-count-rate high-time-resolution real-time digital neutron-gamma discrimination for fast liquid detectors
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作者 Hui‑Yin Shen Jing‑Long Zhang +1 位作者 Jie Zhang Jian‑Hang Zhou 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第8期101-113,共13页
Fast neutron flux measurements with high count rates and high time resolution have important applications in equipment such as tokamaks.In this study,real-time neutron and gamma discrimination was implemented on a sel... Fast neutron flux measurements with high count rates and high time resolution have important applications in equipment such as tokamaks.In this study,real-time neutron and gamma discrimination was implemented on a self-developed 500-Msps,12-bit digitizer,and the neutron and gamma spectra were calculated directly on an FPGA.A fast neutron flux measurement system with BC-501A and EJ-309 liquid scintillator detectors was developed and a fast neutron measurement experiment was successfully performed on the HL-2 M tokamak at the Southwestern Institute of Physics,China.The experimental results demonstrated that the system obtained the neutron and gamma spectra with a time accuracy of 1 ms.At count rates of up to 1 Mcps,the figure of merit was greater than 1.05 for energies between 50 keV and 2.8 MeV. 展开更多
关键词 Neutron-gamma discrimination Liquid scintillation detector Real-time spectrum analyzer
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Mixed-ownership Reform:Private Firms’Role in Targeted Poverty Alleviation-A Perspective on Resource Complementarity and Check&Balance
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作者 Ding Hui He Dongxin +1 位作者 Jiang Fuwei Zhang Zhining 《China Economist》 2024年第5期25-47,共23页
Targeted poverty alleviation(TPA)serves as a winning formula for fighting poverty and has generated valuable experiences for achieving common prosperity.The mixed-ownership reform has enhanced corporate economic perfo... Targeted poverty alleviation(TPA)serves as a winning formula for fighting poverty and has generated valuable experiences for achieving common prosperity.The mixed-ownership reform has enhanced corporate economic performance.However,further testing is required to assess whether enterprises contribute to the improvement of distribution by participating in TPA.Taking A-share-listed private enterprises between 2016 and 2021 as research samples,we conducted an investigation into the extent and manner in which the mixed-ownership reform contributes to TPA.Our research reveals that a higher proportion of state capital equity participation is correlated with a greater level of private enterprises’contribution to TPA.This indicates that the mixed-ownership reform is beneficial for prompting private enterprises to shoulder responsibilities for building a society of common prosperity.As shown by the mechanism test,state capital equity participation encourages private enterprises to contribute to TPA primarily by alleviating corporate financing constraints through the resource complementarity effect.In contrast,the check&balance effect of promoting corporate poverty alleviation by mitigating the principal-agent problem has not yet been significantly demonstrated.Regarding the poverty alleviation model,state capital equity participation prompts private enterprises to contribute to TPA through industrial development,educational investment,and environmental protection,emphasizing a combination of providing external assistance and cultivating endogenous development capacity.In terms of TPA regions,state capital equity participation plays a significant role in supporting economically less-developed regions,regions with high unemployment rates,and central and western regions.This paper provides new empirical evidence for deepening mixed-ownership reforms and advancing common prosperity. 展开更多
关键词 Mixed ownership TPA state capital resource complementarity check&balance
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The Influence of Price Discrimination from Airports on the Route Development Behavior of Airlines
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作者 Daniel Schnitzler 《Journal of Civil Engineering and Architecture》 2024年第1期17-29,共13页
Given the prominence and magnitude of airport incentive schemes,it is surprising that literature hitherto remains silent as to their effectiveness.In this paper,the relationship between airport incentive schemes and t... Given the prominence and magnitude of airport incentive schemes,it is surprising that literature hitherto remains silent as to their effectiveness.In this paper,the relationship between airport incentive schemes and the route development behavior of airlines is analyzed.Because of rare and often controversial findings in the extant literature regarding relevant influencing variables for attracting airlines at an airport,expert interviews are used as a complement to formulate testable hypotheses in this regard.A fixed effects regression model is used to test the hypotheses with a dataset that covers all seat capacity offered at the 22 largest German commercial airports in the week 46 from 2004 to 2011.It is found that incentives from primary choice,as well as secondary choice airports,have a significant influence on Low Cost Carriers.Furthermore,Low Cost Carriers,in general,do not leave any of both types of airports when the incentives cease.In the case of Network Carriers,no case is found where one joins a primary choice airport and receives an incentive.Insufficient data between Network Carriers and secondary choice airports in the time when incentives have ceased means that no statement can be given. 展开更多
关键词 AIRLINE rout development price discrimination
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The Impact of Short Selling Disclosure Regulatory Constraint on the Lending Market and Stock Ownership
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作者 Geoffrey Ducournau Jinliang Li +2 位作者 Yan Li Zigan Wang Qie Ellie Yin 《Journal of Modern Accounting and Auditing》 2024年第3期99-114,共16页
We examine the impact of the short sell disclosure(SSD)regime on the stock lending market and investor behaviors,employing a staggered difference-indifference(DiD)methodology.Our research reveals that the introduction... We examine the impact of the short sell disclosure(SSD)regime on the stock lending market and investor behaviors,employing a staggered difference-indifference(DiD)methodology.Our research reveals that the introduction of the disclosure regime enhances market transparency,resulting in a diminished appeal of stock ownership in the lending market for active investors.This shift is accompanied by a reduction in information leakage risks and longer loan durations.Specifically,our analysis reveals a significant decrease in the risk of loan recall by 4.87%,accompanied by an average increase of 23.72%in loan duration for short selling activities.Furthermore,the cost associated with short-sell disclosure causes a decline in both lending supply and short demand. 展开更多
关键词 short sell disclosure stock equity lending market stock ownership
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Property Attribute and Property Ownership of Virtual Property
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作者 Mengshuai Zhu 《Proceedings of Business and Economic Studies》 2024年第5期43-48,共6页
Virtual property has increasingly become a key issue,particularly regarding its nature,ownership,and goodwill acquisition,all of which are worthy of study.Analyzing these issues can contribute to a better understandin... Virtual property has increasingly become a key issue,particularly regarding its nature,ownership,and goodwill acquisition,all of which are worthy of study.Analyzing these issues can contribute to a better understanding of how to develop laws and regulations to protect virtual property. 展开更多
关键词 Virtual property ownership Goodwill acquisition
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Research on Mixed Ownership Reform of State-Owned Enterprises from the Perspective of Marxist Political Economy
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作者 Honghong Lu 《Proceedings of Business and Economic Studies》 2024年第5期61-67,共7页
Under China’s socialist system,state-owned enterprises are key forces driving the economic trajectory and providing strong momentum.These enterprises not only bear the crucial responsibility of advancing the process ... Under China’s socialist system,state-owned enterprises are key forces driving the economic trajectory and providing strong momentum.These enterprises not only bear the crucial responsibility of advancing the process of national modernization but also serve as the core of the national economic lifeline through their irreplaceable status and function amidst changing times.In the new era,with the advent of the technological revolution and the wave of globalization,state-owned enterprises face unprecedented opportunities and challenges.As a significant aspect of state-owned enterprise reform,the mixed ownership reform is not only a transformation in the structure of enterprise ownership but also a reflection of China’s broader,comprehensive reform efforts.By deeply advancing this reform,it will help optimize the allocation of state-owned assets and significantly boost technological and management innovation within state-owned enterprises,ensuring their competitiveness in the intense market environment.Therefore,this paper will conduct an in-depth analysis of the mixed ownership reform of state-owned enterprises from the perspective of Marxist political economy. 展开更多
关键词 Marxist political economy State-owned enterprise reform Mixed ownership
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粮食气味物质的提取、关键组分判别及其在储藏中的应用研究进展
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作者 李慧 洪习文 +1 位作者 王争艳 王艳艳 《食品科学》 EI CAS 北大核心 2025年第1期266-273,共8页
粮食气味物质受粮食种类、储藏条件、储藏时间及是否受有害生物污染等多种因素影响,气味物质种类及含量能够及时反映粮食是否变质或受有害生物危害。首先,本文概述目前常用的粮食气味物质的提取和鉴定技术,总结不同状态粮食气味物质组成... 粮食气味物质受粮食种类、储藏条件、储藏时间及是否受有害生物污染等多种因素影响,气味物质种类及含量能够及时反映粮食是否变质或受有害生物危害。首先,本文概述目前常用的粮食气味物质的提取和鉴定技术,总结不同状态粮食气味物质组成,发现烷烃类、酸类、醛类和醇类等物质赋予粮食特有的气味,而不同的储藏环境和粮食状态下,其气味物质存在较大差异。其次,探讨粮食中特征气味物质的分析方法,梳理粮食关键气味物质可能的代谢途径,归纳水稻和小麦中特征气味物质,其中稻谷中特征气味物质2-乙酰基-1-吡咯啉的生成机制也已得到初步确认。最后,对气味物质在粮食安全储藏领域的应用进行概述,提出深入分析、挖掘粮食气味物质数据,构建新型预测模型以快速、精准检测粮食品质将成为未来粮食气味物质研究领域的重要方向;同时,部分气味物质也被证实对粮仓中有害生物具有防控作用,将成为未来研发新型绿色储粮药剂的重要来源。 展开更多
关键词 粮食 气味物质 判别方法 代谢途径 安全储藏
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利用区域地震资料监测朝鲜地下核试验的研究进展
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作者 赵连锋 谢小碧 +3 位作者 何熹 张蕾 杨庚 姚振兴 《地球与行星物理论评(中英文)》 2025年第2期148-156,共9页
根据朝鲜6次地下核试验在中国东北及邻近地区产生的宽频带区域地震资料,中国科学院地质与地球物理研究所地震学学科组发展了一套用于监测地下核试验的地震学方法,主要包括震级测量和当量估计、高精度震中定位以及爆炸与天然地震事件识别... 根据朝鲜6次地下核试验在中国东北及邻近地区产生的宽频带区域地震资料,中国科学院地质与地球物理研究所地震学学科组发展了一套用于监测地下核试验的地震学方法,主要包括震级测量和当量估计、高精度震中定位以及爆炸与天然地震事件识别等.在全球范围内,存在多个用于震级-当量转换的经验公式,确定何种公式适合于朝鲜半岛地区至关重要.通过搜集一组用于地震测深的化学爆炸的当量和埋深,并以这些已知爆炸源作为量规事件,能够标定朝鲜地下核试验场的震级-当量关系,从而实现对朝鲜地下核爆进行当量估计.在精确定位方面,发展了利用多事件之间波形互相关方法精确测定它们之间的走时差从而完成高精度相对震中定位.通过进一步利用Pn和Pg等多震相数据还实现了对核爆深度的相对定位.在爆炸震源识别方面,利用统计处理方法分析研究了不同类型事件所产生地震波的特征,包括6次地下核试验、4次天然地震和3次化学爆炸,以及一些矿区塌陷等.结果发现P和S类型波的振幅比,例如Pn/Lg、Pg/Lg和Pn/Sn等,在2 Hz以上能够较好区分各类震源.其中爆炸震源产生的振幅比显著高于天然地震的值.特别是,通过计算谱振幅比的台网平均值能够显著提高识别的可靠性.利用中国东北和附近地区地震台网所提供的数据可以准确地将朝鲜地下核试验从周边天然地震事件中识别出来.该方法同时得到化学爆炸的P/S谱振幅比值介于核爆炸和天然地震的群组之间. 展开更多
关键词 爆炸当量估计 震源相对定位 爆炸和天然地震识别 朝鲜地下核试验
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专精特新家族企业数字化转型的实践路径——基于面板数据的动态fsQCA分析
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作者 周立新 周汉威 屈彩萍 《工业技术经济》 北大核心 2025年第1期85-95,共11页
本文运用动态fsQCA分析方法对前4批A股上市的专精特新家族企业数据进行组态分析,分析其数字化转型路径,结果发现:(1)技术、组织、环境3个层面7个前因条件均不构成专精特新家族企业数字化转型的必要条件,但家族所有权、市场化程度的必要... 本文运用动态fsQCA分析方法对前4批A股上市的专精特新家族企业数据进行组态分析,分析其数字化转型路径,结果发现:(1)技术、组织、环境3个层面7个前因条件均不构成专精特新家族企业数字化转型的必要条件,但家族所有权、市场化程度的必要性存在明显的时间变化趋势;(2)驱动专精特新家族企业高数字化转型的路径有4条,即“市场主导-技术辅助”、“技术主导-环境支持”、“去家族化-多要素复合驱动”、“家族控制主导”4条驱动路径,其中技术层面的前因条件尤为重要;导致专精特新家族企业非高数字化转型的路径有两条,其中技术层面前因条件全部缺失;(3)时间维度上,各路径在绝大多数年份均具有较强的解释力度;空间维度上,“市场主导-技术辅助”、“市场主导-环境支持”、“家族控制主导”的覆盖度在不同类型企业中存在差异。 展开更多
关键词 专精特新 家族企业 数字化转型 fsQCA TOE框架 家族所有权 家族管理权 技术创新
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碳配额所有权解释进路下的碳排放权研究
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作者 胡静 董宜君 《河北大学学报(哲学社会科学版)》 2025年第1期135-149,共15页
我国对碳排放权概念的使用经历了从经济学语境拓展到法学语境的过程。碳排放权的本来面目是经济学上的产权。若将其代入法学语境,碳排放权的性质应为法律权利的客体,地位相当于碳配额。目前法学上将碳排放权作为一项法律权利进行诠释可... 我国对碳排放权概念的使用经历了从经济学语境拓展到法学语境的过程。碳排放权的本来面目是经济学上的产权。若将其代入法学语境,碳排放权的性质应为法律权利的客体,地位相当于碳配额。目前法学上将碳排放权作为一项法律权利进行诠释可能会造成该概念理解上的混乱和实际应用上的困难。基于我国碳交易制度的实践,以碳配额作为权利客体,以权利人对碳配额的占有(持有)、使用(排放)、处分(转让、设立担保)等为权利内容的碳配额所有权对制度更有解释力和指引力。若将碳排放权视为排放碳的权利,则行使碳排放权实质上就是运用碳配额所有权的使用权能。碳配额所有权具有广义的政策性,以“行政本质、民法路径”为特点,以减排目标的实现为根本遵循,是以实行公法义务为目的的工具性权利,区别于作为目的性权利的传统民事权利。碳配额所有权的成立以配额的界定为前提,碳配额、核证自愿减排量的界定依赖碳排放量和减排量的检测和认定,基于此,行政机关应对数据质量进行严格监管。 展开更多
关键词 碳排放权交易 碳排放权 碳配额所有权 配额 核证自愿减排量
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Perceptual Learning of Grate Orientation Discrimination in Cats 被引量:1
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作者 华田苗 万安 +2 位作者 王赦焱 梅斌 孙庆艳 《Zoological Research》 CAS CSCD 北大核心 2007年第1期95-100,共6页
Perceptual learning of orientation discrimination was investigated using cats. Two adult cats (Cat 1 and 2) were trained to monocularly discriminate between two static striped sinusoidal grates with 30° orienta... Perceptual learning of orientation discrimination was investigated using cats. Two adult cats (Cat 1 and 2) were trained to monocularly discriminate between two static striped sinusoidal grates with 30° orientation difference. After greater than 80% correct performance was reached, cats were then required to monocularly perform a discrimination between two grates with consecutively shifting orientation difference(2°, 4°, 6°, 8°, 10°, 12°, 16°, 20°, 24°, 30°) . The staircase method (two correct-down and one error-up) was applied throughout the training to track the threshold of orientation difference that cats could detect. The performance of detecting grates with varied orientation difference was measured respectively for beth trained and untrained eyes before and after training. Our results showed that the learning effect of discrimination for grates with a fixed orientation difference transferred completely from the trained eye to the untrained eye, whereas the inter-eye transfer for detecting °ates with gradually reducing orientation difference was almost nonegrates. The two opposite learning effects in the same subject strongly suggest that different information processing mechanisms might mediate the learning processes. 展开更多
关键词 Perceptual learning Orientation discrimination CAT
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Modeling household car ownership using ordered logistic regression model 被引量:3
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作者 邓一凌 过秀成 《Journal of Southeast University(English Edition)》 EI CAS 2014年第4期500-505,共6页
Considering both the discrete and ordered nature of the household car ownership an ordered logistic regression model to predict household car ownership is established by using the data of Nanjing Household Travel Surv... Considering both the discrete and ordered nature of the household car ownership an ordered logistic regression model to predict household car ownership is established by using the data of Nanjing Household Travel Survey in the year 2012. The model results show that some household characteristics such as the number of driver licenses household income and home location are significant.Yet the intersection density indicating the street patterns of home location and the dummy near the subway and the bus stop density indicating the transit accessibility of home location are insignificant.The model estimation obtains a good γ2 the goodness of fit of the model and the model validation also shows a good performance in prediction.The marginal effects of all the significant explanatory variables are calculated to quantify the odds change in the household car ownership following a one-unit change in the explanatory variables. 展开更多
关键词 household car ownership ordered logisticregression model marginal effect household characteristics neighborhood characteristics
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Response of Photosynthesis, Growth, Carbon Isotope Discrimination and Osmotic Tolerance of Rice to Elevated CO_2 被引量:2
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作者 彭长连 段俊 +2 位作者 林桂珠 陈贻竹 彭少麟 《Acta Botanica Sinica》 CSCD 2002年第1期76-81,共6页
Four rice ( Oryza sativa L.) cultivars 'IR72', 'Tesanai 2', 'Guichao 2' and 'IIyou 4480' were grown in two plastic house (15 m×3 m) with 35 μmol/mol and 60 μmol/mol CO 2 conc... Four rice ( Oryza sativa L.) cultivars 'IR72', 'Tesanai 2', 'Guichao 2' and 'IIyou 4480' were grown in two plastic house (15 m×3 m) with 35 μmol/mol and 60 μmol/mol CO 2 concentration which was controlled by computer. As compared with rice at ambient 35 μmol/mol CO 2, the changes in photosynthetic rate at elevated CO 2 showed up_regulation ('IR72' and 'Tesanai 2'), stable (unchanged) in 'Guichao 2' and down_regulation type ('IIyou 4480'). Growth rate, panicle weight, integrated water use efficiency (WUE) calculated from Δ 13 C and the capacity of scavenging DPPH · (1,1_diphenyl_2_picrylhydrazyl) free radical were increased at elevated CO 2. An increment in total biomass was observed in three cultivars by elevated CO 2, with the exception of 'IIyou 4480'. Ratios of panicle weight/total biomass were altered to different extents in tested cultivars by elevated CO 2. When leaf segments were subjected to PEG osmotic stress, the electrolyte leakage rate from leaves grown at elevated CO 2 was less than that at 35 μmol/mol CO 2. Those intraspecific variations of rice imply a possibility for selecting cultivars with maximal productivity and high tolerance to stresses adapted to elevated CO 2 in the future. 展开更多
关键词 rice cultivars elevated CO 2 PHOTOSYNTHESIS water use efficiency 13 C discrimination osmotic tolerance
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量子核判别分析算法
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作者 康榕乘 余凯 +2 位作者 张新 林崧 郭躬德 《郑州大学学报(理学版)》 CAS 北大核心 2025年第1期61-66,共6页
核判别分析法通过核函数扩展了线性判别分析对非线性数据的处理能力,成为模式识别领域中一个重要的分支。然而,随着数据的指数增长,经典核判别分析算法在提取特征时会消耗大量计算资源。针对这一问题,利用量子叠加性和并行性提出了一种... 核判别分析法通过核函数扩展了线性判别分析对非线性数据的处理能力,成为模式识别领域中一个重要的分支。然而,随着数据的指数增长,经典核判别分析算法在提取特征时会消耗大量计算资源。针对这一问题,利用量子叠加性和并行性提出了一种量子核判别分析算法。首先,借助量子随机存储器技术与控制旋转操作构造需要的类间矩阵和类内矩阵所对应的密度算子;然后,融入线性方程的求解思路并行获取特征态。理论分析表明,所提算法与经典算法相比具有指数级加速。 展开更多
关键词 量子机器学习 非线性判别分析 核函数 特征提取 量子厄米特链积 相位估计
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垄断势力视角下平台大数据杀熟的价格歧视机理 被引量:1
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作者 熊浩 赵晓岚 +1 位作者 鄢慧丽 徐宇淼 《海南大学学报(人文社会科学版)》 2025年第1期227-235,共9页
大数据杀熟问题近年来受到各界的广泛关注,政府出台了一系列有关大数据杀熟治理的政策文件。然而,诸多法规相互交叉、竞合,给监管执行造成了巨大的困难。大数据杀熟愈演愈烈,导致了消费者群体与涉事平台企业之间存在严重的信任危机。为... 大数据杀熟问题近年来受到各界的广泛关注,政府出台了一系列有关大数据杀熟治理的政策文件。然而,诸多法规相互交叉、竞合,给监管执行造成了巨大的困难。大数据杀熟愈演愈烈,导致了消费者群体与涉事平台企业之间存在严重的信任危机。为了能更好地理解和治理大数据杀熟,本文深入分析了垄断势力视角下平台大数据杀熟的价格歧视机理。通过分析,揭示了大数据杀熟的经济逻辑为(:1)垄断势力是形成大数据杀熟的源泉(;2)大数据杀熟本质是不公平的高价价格歧视。在以上分析的基础上,本文对大数据杀熟的本质、认识误区和治理思路进行了分析,指出大数据杀熟治理的关键是反垄断和防欺诈。总之,本研究通过对大数据杀熟垄断势力下价格歧视机理的分析,厘清了大数据杀熟与价格歧视和精准营销的区别,从而为正确认识大数据杀熟和有效抑制大数据杀熟提供参考。 展开更多
关键词 大数据杀熟 平台经济 价格歧视 垄断势力
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