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Bearing capacity prediction of open caissons in two-layered clays using five tree-based machine learning algorithms 被引量:1
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作者 Rungroad Suppakul Kongtawan Sangjinda +3 位作者 Wittaya Jitchaijaroen Natakorn Phuksuksakul Suraparb Keawsawasvong Peem Nuaklong 《Intelligent Geoengineering》 2025年第2期55-65,共11页
Open caissons are widely used in foundation engineering because of their load-bearing efficiency and adaptability in diverse soil conditions.However,accurately predicting their undrained bearing capacity in layered so... Open caissons are widely used in foundation engineering because of their load-bearing efficiency and adaptability in diverse soil conditions.However,accurately predicting their undrained bearing capacity in layered soils remains a complex challenge.This study presents a novel application of five ensemble machine(ML)algorithms-random forest(RF),gradient boosting machine(GBM),extreme gradient boosting(XGBoost),adaptive boosting(AdaBoost),and categorical boosting(CatBoost)-to predict the undrained bearing capacity factor(Nc)of circular open caissons embedded in two-layered clay on the basis of results from finite element limit analysis(FELA).The input dataset consists of 1188 numerical simulations using the Tresca failure criterion,varying in geometrical and soil parameters.The FELA was performed via OptumG2 software with adaptive meshing techniques and verified against existing benchmark studies.The ML models were trained on 70% of the dataset and tested on the remaining 30%.Their performance was evaluated using six statistical metrics:coefficient of determination(R²),mean absolute error(MAE),root mean squared error(RMSE),index of scatter(IOS),RMSE-to-standard deviation ratio(RSR),and variance explained factor(VAF).The results indicate that all the models achieved high accuracy,with R²values exceeding 97.6%and RMSE values below 0.02.Among them,AdaBoost and CatBoost consistently outperformed the other methods across both the training and testing datasets,demonstrating superior generalizability and robustness.The proposed ML framework offers an efficient,accurate,and data-driven alternative to traditional methods for estimating caisson capacity in stratified soils.This approach can aid in reducing computational costs while improving reliability in the early stages of foundation design. 展开更多
关键词 two-layered clay Open caisson Tree-based algorithms FELA Machine learning
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Countability of Infinite Paths in the Infinity Tree: Proof of the Continuum Hypothesis in a Non-Cantorian Infinity Theory
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作者 Philip C. Jackson 《Advances in Pure Mathematics》 2025年第1期73-90,共18页
A previous paper showed that the real numbers between 0 and 1 could be represented by an infinite tree structure, called the ‘infinity tree’, which contains only a countably infinite number of nodes and arcs. This p... A previous paper showed that the real numbers between 0 and 1 could be represented by an infinite tree structure, called the ‘infinity tree’, which contains only a countably infinite number of nodes and arcs. This paper discusses how a finite-state Turing machine could, in a countably infinite number of state transitions, write all the infinite paths in the infinity tree to a countably infinite tape. Hence it is argued that the real numbers in the interval [0, 1] are countably infinite in a non-Cantorian theory of infinity based on Turing machines using countably infinite space and time. In this theory, Cantor’s Continuum Hypothesis can also be proved. And in this theory, it follows that the power set of the natural numbers P(ℕ) is countably infinite, which contradicts the claim of Cantor’s Theorem for the natural numbers. However, this paper does not claim there is an error in Cantor’s arguments that [0, 1] is uncountably infinite. Rather, this paper considers the situation as a paradox, resulting from different choices about how to represent and count the continuum of real numbers. 展开更多
关键词 INFINITY Countable UNCOUNTABLE Diagonalization Real Numbers Infinity Tree Continuum hypothesis Turing Machine Infinite Time Turing Machine Non-Cantorian
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Pitch Motion Analysis of a Submerged Cylindrical Structure in a Two-layer Fluid
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作者 Champak Kr.Neog Mohammad Hassan 《哈尔滨工程大学学报(英文版)》 2025年第5期984-997,共14页
This study investigates the effects of radiation force due to the rotational pitch motion of a wave energy device,which comprises a coaxial bottom-mounted cylindrical caisson in a two-layer fluid,along with a submerge... This study investigates the effects of radiation force due to the rotational pitch motion of a wave energy device,which comprises a coaxial bottom-mounted cylindrical caisson in a two-layer fluid,along with a submerged cylindrical buoy.The system is modeled as a two-layer fluid with infinite horizontal extent and finite depth.The radiation problem is analyzed in the context of linear water waves.The fluid domain is divided into outer and inner zones,and mathematical solutions for the pitch radiating potential are derived for the corresponding boundary valve problem in these zones using the separation of variables approach.Using the matching eigenfunction expansion method,the unknown coefficients in the analytical expression of the radiation potentials are evaluated.The resulting radiation potential is then used to compute the added mass and damping coefficients.Several numerical results for the added mass and damping coefficients are investigated for numerous parameters,particularly the effects of the cylinder radius,the draft of the submerged cylinder,and the density proportion between the two fluid layers across different frequency ranges.The major findings are presented and discussed. 展开更多
关键词 Pitch radiation Eigenfunction expansion two-layer Hydrodynamic coefficients Submerged cylinder Bottom-mounted cylinder
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Consequences of Invariant Functions for the Riemann Hypothesis
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作者 Michael Mark Anthony 《Advances in Pure Mathematics》 2025年第1期36-72,共37页
This paper attempts to form a bridge between a sum of the divisors function and the gamma function, proposing a novel approach that could have significant implications for classical problems in number theory, specific... This paper attempts to form a bridge between a sum of the divisors function and the gamma function, proposing a novel approach that could have significant implications for classical problems in number theory, specifically the Robin inequality and the Riemann hypothesis. The exploration of using invariant properties of these functions to derive insights into twin primes and sequential primes is a potentially innovative concept that deserves careful consideration by the mathematical community. 展开更多
关键词 LambertW Function Principal Branch Riemann hypothesis ITERATIONS Robin Inequality Robin Integers INVARIANCE Gauss Gamma Function Li-Function Prime Counting Function Sums of Divisors INVARIANCE PRIMES Twin Primes
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A Two-Layer Network Intrusion Detection Method Incorporating LSTM and Stacking Ensemble Learning
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作者 Jun Wang Chaoren Ge +4 位作者 Yihong Li Huimin Zhao Qiang Fu Kerang Cao Hoekyung Jung 《Computers, Materials & Continua》 2025年第6期5129-5153,共25页
Network Intrusion Detection System(NIDS)detection of minority class attacks is always a difficult task when dealing with attacks in complex network environments.To improve the detection capability of minority-class at... Network Intrusion Detection System(NIDS)detection of minority class attacks is always a difficult task when dealing with attacks in complex network environments.To improve the detection capability of minority-class attacks,this study proposes an intrusion detection method based on a two-layer structure.The first layer employs a CNN-BiLSTM model incorporating an attention mechanism to classify network traffic into normal traffic,majority class attacks,and merged minority class attacks.The second layer further segments the minority class attacks through Stacking ensemble learning.The datasets are selected from the generic network dataset CIC-IDS2017,NSL-KDD,and the industrial network dataset Mississippi Gas Pipeline dataset to enhance the generalization and practical applicability of the model.Experimental results show that the proposed model achieves an overall detection accuracy of 99%,99%,and 95%on the CIC-IDS2017,NSL-KDD,and industrial network datasets,respectively.It also significantly outperforms traditional methods in terms of detection accuracy and recall rate for minority class attacks.Compared with the single-layer deep learning model,the two-layer structure effectively reduces the false alarm rate while improving the minority-class attack detection performance.The research in this paper not only improves the adaptability of NIDS to complex network environments but also provides a new solution for minority-class attack detection in industrial network security. 展开更多
关键词 two-layer architecture minority class attack stacking ensemble learning network intrusion detection
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Early cancer diagnosis via interpretable two-layer machine learning of plasma extracellular vesicle long RNA
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作者 Shi-Cai Liu Han Zhang 《World Journal of Gastrointestinal Oncology》 2025年第11期254-277,共24页
BACKGROUND The early diagnosis rate of pancreatic ductal adenocarcinoma(PDAC)is low and the prognosis is poor.It is important to develop an interpretable noninvasive early diagnostic model in clinical practice.AIM To ... BACKGROUND The early diagnosis rate of pancreatic ductal adenocarcinoma(PDAC)is low and the prognosis is poor.It is important to develop an interpretable noninvasive early diagnostic model in clinical practice.AIM To develop an interpretable noninvasive early diagnostic model for PDAC using plasma extracellular vesicle long RNA(EvlRNA).METHODS The diagnostic model was constructed based on plasma EvlRNA data.During the process of establishing the model,EvlRNA-index was introduced,and four algorithms were adopted to calculate EvlRNA-index.After the model was successfully constructed,performance evaluation was conducted.A series of bioinformatics methods were adopted to explore the potential mechanism of EvlRNA-index as the input feature of the model.And the relationship between key characteristics and PDAC were explored at the single-cell level.RESULTS A novel interpretable machine learning framework was developed based on plasma EvlRNA.In this framework,a two-layer classifier was established.A new concept was proposed:EvlRNA-index.Based on EvlRNA-index,a cancer diagnostic model was established,and a good diagnostic effect was achieved.The accuracy of PDACandCPvsHealth-Probabilistic PCA Index-SVM(PDAC and chronic pancreatitis vs health-probabilistic principal component analysis index-support vector machine)(1-18)was 91.51%,with Mathew’s correlation coefficient 0.7760 and area under the curve 0.9560.In the second layer of the model,the accuracy of PDACvsCP-Probabilistic PCA Index-RF(PDAC vs chronic pancreatitis-probabilistic principal component analysis index-random forest)(2-17)was 93.83%,with Mathew’s correlation coefficient 0.8422 and area under the curve 0.9698.Forty-nine PDAC-related genes were identified,among which 16 were known,inferring that the remaining ones were also PDAC-related genes.CONCLUSION An interpretable two-layer machine learning framework was proposed for early diagnosis and prediction of PDAC based on plasma EvlRNA,providing new insights into the clinical value of EvlRNA. 展开更多
关键词 Pancreatic ductal adenocarcinoma Extracellular vesicle long RNA Noninvasive early diagnosis Interpretable machine learning two-layer classifier
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A Two-Layer UAV Cooperative Computing Offloading Strategy Based on Deep Reinforcement Learning
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作者 Zhang Jianfei Wang Zhen +1 位作者 Hu Yun Chang Zheng 《China Communications》 2025年第10期251-268,共18页
In the wake of major natural disasters or human-made disasters,the communication infrastruc-ture within disaster-stricken areas is frequently dam-aged.Unmanned aerial vehicles(UAVs),thanks to their merits such as rapi... In the wake of major natural disasters or human-made disasters,the communication infrastruc-ture within disaster-stricken areas is frequently dam-aged.Unmanned aerial vehicles(UAVs),thanks to their merits such as rapid deployment and high mobil-ity,are commonly regarded as an ideal option for con-structing temporary communication networks.Con-sidering the limited computing capability and battery power of UAVs,this paper proposes a two-layer UAV cooperative computing offloading strategy for emer-gency disaster relief scenarios.The multi-agent twin delayed deep deterministic policy gradient(MATD3)algorithm integrated with prioritized experience replay(PER)is utilized to jointly optimize the scheduling strategies of UAVs,task offloading ratios,and their mobility,aiming to diminish the energy consumption and delay of the system to the minimum.In order to address the aforementioned non-convex optimiza-tion issue,a Markov decision process(MDP)has been established.The results of simulation experiments demonstrate that,compared with the other four base-line algorithms,the algorithm introduced in this paper exhibits better convergence performance,verifying its feasibility and efficacy. 展开更多
关键词 cooperative computational offloading deep reinforcement learning mobile edge computing prioritized experience replay two-layer unmanned aerial vehicles
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The dilatancy-diffusion hypothesis,earthquake prediction,and operational earthquake forecasting:In memory of Professor Amos Nur on the 50th Anniversary of the 1975 Haicheng Earthquake
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作者 Lanbo Liu 《Earthquake Science》 2025年第5期465-484,共20页
Dilatancy is referred to the phenomenon of volume increase that occurs when a material is deformed.Dilatancy theory originated in geomechanics for the study of the behavior of granular materials.Later it is expanded t... Dilatancy is referred to the phenomenon of volume increase that occurs when a material is deformed.Dilatancy theory originated in geomechanics for the study of the behavior of granular materials.Later it is expanded to the case of more brittle materials like rocks when it is subjected to the load of varying effective stress and starts to crack and deform,then named the dilatancy-diffusion hypothesis.This hypothesis was developed to explain the changes in rock volume and pore pressure that occur prior to and during fault slip,which can influence earthquake dynamics.Dilatancy-fluid diffusion is a significant concept in understanding the seismogenic process and has served as the major theoretical pillar for earthquake prediction by its classic definition.This paper starts with the recount of fundamental laboratory experiments on granular materials and rocks,then conducts review and examination of the history for using the dilatancy-diffusion hypothesis to interpret the‘prediction’of the 1975 Haicheng Earthquake and other events.The Haicheng Earthquake is the first significant event to be interpreted with the dilatancy-diffusion hypothesis in the world.As one pivotal figure in the development of the dilatancy-diffusion hypothesis for earthquake prediction Professor Amos Nur of Stanford University worked tirelessly to attract societal attention to this important scientific and humanistic issue.As a deterministic physical model the dilatancy-diffusion hypothesis intrinsically bears the deficit to interpret the stochastic seismogenic process.With the emergence of deep learning and its successful applications to many science and technology fields,we may see a possibility to overcome the shortcoming of the current state of the theory with the addition of empirical statistics to push the operational earthquake forecasting approach with the addition of the physicallyinformed neural networks which adopt the dilatancy-diffusion hypothesis as one of its embedded physical relations,to uplift the seismic risk reduction to a new level for saving lives and reducing the losses. 展开更多
关键词 dilatancy-diffusion hypothesis Amos Nur Haicheng Earthquake earthquake prediction operational earthquake forecasting(OEF) physically-informed neural networks(PINNs)
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A Two-Layer Encoding Learning Swarm Optimizer Based on Frequent Itemsets for Sparse Large-Scale Multi-Objective Optimization 被引量:2
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作者 Sheng Qi Rui Wang +3 位作者 Tao Zhang Xu Yang Ruiqing Sun Ling Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1342-1357,共16页
Traditional large-scale multi-objective optimization algorithms(LSMOEAs)encounter difficulties when dealing with sparse large-scale multi-objective optimization problems(SLM-OPs)where most decision variables are zero.... Traditional large-scale multi-objective optimization algorithms(LSMOEAs)encounter difficulties when dealing with sparse large-scale multi-objective optimization problems(SLM-OPs)where most decision variables are zero.As a result,many algorithms use a two-layer encoding approach to optimize binary variable Mask and real variable Dec separately.Nevertheless,existing optimizers often focus on locating non-zero variable posi-tions to optimize the binary variables Mask.However,approxi-mating the sparse distribution of real Pareto optimal solutions does not necessarily mean that the objective function is optimized.In data mining,it is common to mine frequent itemsets appear-ing together in a dataset to reveal the correlation between data.Inspired by this,we propose a novel two-layer encoding learning swarm optimizer based on frequent itemsets(TELSO)to address these SLMOPs.TELSO mined the frequent terms of multiple particles with better target values to find mask combinations that can obtain better objective values for fast convergence.Experi-mental results on five real-world problems and eight benchmark sets demonstrate that TELSO outperforms existing state-of-the-art sparse large-scale multi-objective evolutionary algorithms(SLMOEAs)in terms of performance and convergence speed. 展开更多
关键词 Evolutionary algorithms learning swarm optimiza-tion sparse large-scale optimization sparse large-scale multi-objec-tive problems two-layer encoding.
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Transient responses of double-curved sandwich two-layer shells resting on Kerr's foundations with laminated three-phase polymer/GNP/fiber surface and auxetic honeycomb core subjected to the blast load
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作者 Nguyen Thi Hai Van Thi Hong Nguyen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期222-247,共26页
This work uses refined first-order shear theory to analyze the free vibration and transient responses of double-curved sandwich two-layer shells made of auxetic honeycomb core and laminated three-phase polymer/GNP/fib... This work uses refined first-order shear theory to analyze the free vibration and transient responses of double-curved sandwich two-layer shells made of auxetic honeycomb core and laminated three-phase polymer/GNP/fiber surface subjected to the blast load.Each of the two layers that make up the double-curved shell structure is made up of an auxetic honeycomb core and two laminated sheets of three-phase polymer/GNP/fiber.The exterior is supported by a Kerr elastic foundation with three characteristics.The key innovation of the proposed theory is that the transverse shear stresses are zero at two free surfaces of each layer.In contrast to previous first-order shear deformation theories,no shear correction factor is required.Navier's exact solution was used to treat the double-curved shell problem with a single title boundary,while the finite element technique and an eight-node quadrilateral were used to address the other boundary requirements.To ensure the accuracy of these results,a thorough comparison technique is employed in conjunction with credible statements.The problem model's edge cases allow for this kind of analysis.The study's findings may be used in the post-construction evaluation of military and civil works structures for their ability to sustain explosive loads.In addition,this is also an important basis for the calculation and design of shell structures made of smart materials when subjected to shock waves or explosive loads. 展开更多
关键词 Blast load two-layer shell Polymer/GNP/Fiber surface Auxetic honeycomb Shear connectors
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A test of the species confidence hypothesis in dusky damselfish
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作者 Elle Overs Sydney Stump +1 位作者 Isabel Severino Daniel T.Blumstein 《Current Zoology》 SCIE CAS CSCD 2024年第1期79-86,共8页
Visual cues are important in both interspecific and intraspecific communication.The species confidence hypothesis proposes that animals are more attracted to conspecific colors and repelled by colors,not on their bodi... Visual cues are important in both interspecific and intraspecific communication.The species confidence hypothesis proposes that animals are more attracted to conspecific colors and repelled by colors,not on their bodies.Studies on terrestrial lizards and birds have tested the species confidence hypothesis and shown that conspecific colors elicit reduced antipredator behavior.To date,the species confidence hypothesis has not been tested in the marine environment,specifically on coral reefs where color communication is of vital importance.We addressed this knowledge gap by measuring flight initiation distance(the distance an individual moves away from an approaching threat)in dusky damselfish(Stegastes nigricans)in response to an approaching disc of 1 of 4 different color treatments:conspecific,blue,yellow,and black.If the species confidence hypothesis explained variation in damselfish flight initiation distance,then we expected individuals to tolerate closer approaches when approached by a conspecific color.In addition,we calculated the color difference between each stimulus and its corresponding back-ground as a potential alternative explanation for flight responses.Damselfish tolerated the closest approach from the conspecific color stimulus;there were no significant differences between other colors and there was no support for the alternative color difference hypothesis.As with similar terrestrial studies,these results are relevant to ecotourists'choice of swimsuit and wetsuit colors because color choice may modify naturalantipredatorbehavior. 展开更多
关键词 antipredator behavior flight initiation distance risk assessment species confidence hypothesis Stegastes nigricans
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Two-Layer Attention Feature Pyramid Network for Small Object Detection
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作者 Sheng Xiang Junhao Ma +2 位作者 Qunli Shang Xianbao Wang Defu Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期713-731,共19页
Effective small object detection is crucial in various applications including urban intelligent transportation and pedestrian detection.However,small objects are difficult to detect accurately because they contain les... Effective small object detection is crucial in various applications including urban intelligent transportation and pedestrian detection.However,small objects are difficult to detect accurately because they contain less information.Many current methods,particularly those based on Feature Pyramid Network(FPN),address this challenge by leveraging multi-scale feature fusion.However,existing FPN-based methods often suffer from inadequate feature fusion due to varying resolutions across different layers,leading to suboptimal small object detection.To address this problem,we propose the Two-layerAttention Feature Pyramid Network(TA-FPN),featuring two key modules:the Two-layer Attention Module(TAM)and the Small Object Detail Enhancement Module(SODEM).TAM uses the attention module to make the network more focused on the semantic information of the object and fuse it to the lower layer,so that each layer contains similar semantic information,to alleviate the problem of small object information being submerged due to semantic gaps between different layers.At the same time,SODEM is introduced to strengthen the local features of the object,suppress background noise,enhance the information details of the small object,and fuse the enhanced features to other feature layers to ensure that each layer is rich in small object information,to improve small object detection accuracy.Our extensive experiments on challenging datasets such as Microsoft Common Objects inContext(MSCOCO)and Pattern Analysis Statistical Modelling and Computational Learning,Visual Object Classes(PASCAL VOC)demonstrate the validity of the proposedmethod.Experimental results show a significant improvement in small object detection accuracy compared to state-of-theart detectors. 展开更多
关键词 Small object detection two-layer attention module small object detail enhancement module feature pyramid network
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A Two-Layer Optimal Scheduling Strategy for Rural Microgrids Accounting for Flexible Loads
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作者 Guo Zhao Chi Zhang Qiyuan Ren 《Energy Engineering》 EI 2024年第11期3355-3379,共25页
In the context of China’s“double carbon”goals and rural revitalization strategy,the energy transition promotes the large-scale integration of distributed renewable energy into rural power grids.Considering the oper... In the context of China’s“double carbon”goals and rural revitalization strategy,the energy transition promotes the large-scale integration of distributed renewable energy into rural power grids.Considering the operational characteristics of rural microgrids and their impact on users,this paper establishes a two-layer scheduling model incorporating flexible loads.The upper-layer aims to minimize the comprehensive operating cost of the rural microgrid,while the lower-layer aims to minimize the total electricity cost for rural users.An Improved Adaptive Genetic Algorithm(IAGA)is proposed to solve the model.Results show that the two-layer scheduling model with flexible loads can effectively smooth load fluctuations,enhance microgrid stability,increase clean energy consumption,and balance microgrid operating costs with user benefits. 展开更多
关键词 Double carbon flexible loads ruralmicrogrid clean energy consumption two-layer scheduling improved adaptive genetic algorithm
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Definite Answer for Riemann Hypothesis Zeta 3/2 Function Provided by New Material Yb2Si2O7 in Quantum Mechanics
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作者 Hung-Te Henry Su Po-Han Lee 《Journal of Modern Physics》 2024年第9期1409-1429,共21页
This paper indicates the problem of the famous Riemann hypothesis (RH), which has been well-verified by a definite answering method using a Bose-Einstein Condensate (BEC) phase. We adopt mathematical induction, mappin... This paper indicates the problem of the famous Riemann hypothesis (RH), which has been well-verified by a definite answering method using a Bose-Einstein Condensate (BEC) phase. We adopt mathematical induction, mappings, and laser photons governed by electromagnetically induced transparency (EIT) to examine the existence of the RH. In considering the well-developed as Riemann zeta function, we find that the existence of RH has a corrected and self-consistent solution. Specifically, there is the only one pole at s = 1 on the complex plane for Riemann’s functions, which generalizes to all non-trivial zeros while s > 1. The essential solution is based on the BEC phases and on the nature of the laser photon(s). This work also incorporates Heisenberg commutators [ x^,p^]=1/2in the field of quantum mechanics. We found that a satisfactory solution for the RH would be incomplete without the formalism of Heisenberg commutators, BEC phases, and EIT effects. Ultimately, we propose the application of qubits in connection with the RH. 展开更多
关键词 BEC Phases EIT Heisenberg Commutators Laser Photons QUBITS Riemann hypothesis
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The Proof Dilemma of Porter’s Hypothesis:Analysis of Its Verification Difficulties
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作者 Zhiyao Huang Jiajie Qu 《Proceedings of Business and Economic Studies》 2024年第3期109-113,共5页
The Porter Hypothesis,proposed by Michael E.Porter,suggests that stringent environmental regulations can enhance corporate innovation and competitiveness,challenging the traditional view that regulations increase busi... The Porter Hypothesis,proposed by Michael E.Porter,suggests that stringent environmental regulations can enhance corporate innovation and competitiveness,challenging the traditional view that regulations increase business costs.It argues that regulations motivate firms to innovate,leading to improved productivity,cost reductions,and new market opportunities.However,there are proponents and critics in academia regarding the hypothesis.Supporters claim regulations change corporate behavior,reducing agency costs and boosting research and development.Critics argue that if win-win situations exist,businesses would naturally pursue them without regulatory incentives.Key challenges in proving or refuting the hypothesis include its various versions,the difficulty in quantifying innovation and competitiveness,the complex interplay between regulation,innovation,and competitiveness,and the varying impacts across industries and regions.Additionally,the effects may require a long time to manifest,and the hypothesis’s applicability is influenced by evolving environmental policies and market environments.Despite mixed empirical findings,the Porter Hypothesis provides a valuable framework for understanding the relationships among environmental regulation,innovation,and competitiveness,but its validation requires a more comprehensive assessment. 展开更多
关键词 Porter hypothesis Environmental regulations INNOVATE Competitive power
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Joint inversion of gravity and magnetic data for a two-layer model 被引量:1
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作者 江凡 吴健生 王家林 《Applied Geophysics》 SCIE CSCD 2008年第4期331-339,共9页
Based on the synchronous joint gravity and magnetic inversion of single interface by Pilkington and the need of revealing Cenozoic and crystalline basement thickness in the new round of oil-gas exploration, we propose... Based on the synchronous joint gravity and magnetic inversion of single interface by Pilkington and the need of revealing Cenozoic and crystalline basement thickness in the new round of oil-gas exploration, we propose a joint gravity and magnetic inversion methodfor two-layer models by concentrating on the relationship between the change of thicknessI and position of the middle layer and anomaly and discuss the effects of the key parameters. Model tests and application to field data show the validity of this method. 展开更多
关键词 two-layer model joint inversion of gravity and magnetic data Cenozoic andcrystalline basement
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科学工作假说(Working Hypothesis)是科学创新的基础 被引量:12
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作者 刘东生 《第四纪研究》 CAS CSCD 北大核心 2006年第5期673-677,共5页
中国第四纪研究委员会成立50年来,第四纪科学已进于一个新的后第四纪研究时代了。显著的特点是研究工作由描述性向理念性,由区域性向全球性,由学科性向系统科学性迈进。在此过程中“科学工作假说”的不断出现,是促进其生长的动力。在195... 中国第四纪研究委员会成立50年来,第四纪科学已进于一个新的后第四纪研究时代了。显著的特点是研究工作由描述性向理念性,由区域性向全球性,由学科性向系统科学性迈进。在此过程中“科学工作假说”的不断出现,是促进其生长的动力。在1950年代对中国黄土成因的许多不同的假说促进了后来中国黄土研究的发展。当前中国第四纪研究的许多关于全球变化问题的科学假说,将开辟一个第四纪研究的新时代。 展开更多
关键词 科学工作假说 科学创新
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The Enlightment on Task-based Teaching Derived from Input Hypothesis 被引量:1
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作者 周春红 《Sino-US English Teaching》 2006年第4期36-38,43,共4页
Aiming at gradually developing and perfecting the task-based teaching method, the essay, with enlightment from the Krashen's Input Hypothesis, discusses some issues about input, output, activities and teacher's role... Aiming at gradually developing and perfecting the task-based teaching method, the essay, with enlightment from the Krashen's Input Hypothesis, discusses some issues about input, output, activities and teacher's role in this method. 展开更多
关键词 task-based teaching input hypothesis INPUT OUTPUT ACTIVITIES teacher's role
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Rules Governing Pressure Distribution for a Traveling Charge Under the Condition of Lagrange Hypothesis
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作者 罗运军 谭惠民 陈福泰 《Journal of Beijing Institute of Technology》 EI CAS 1999年第2期43-49,共7页
Aim To study the rules governing pressure distribution of traveling charge under the condition of Lagrange hypothesis. Methods\ The study is based on the laws of conservation of momentum and energy. Results\ The gas ... Aim To study the rules governing pressure distribution of traveling charge under the condition of Lagrange hypothesis. Methods\ The study is based on the laws of conservation of momentum and energy. Results\ The gas flow velocity distribution formula at the back of a projectile and the momentum equation of a traveling charge are deduced, and rules governing their pressure distribution under the Lagrange hypothesis conditions are established. The pressure distribution of a traveling charge is compared with that of a conventional charge. Conclusion\ The pressure distribution in the bore of a traveling charge can be accurately predicted. A parabolic pressure distribution type is revealed. 展开更多
关键词 GUN traveling charge interior ballistics pressure distribution Lagrange hypothesis
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人类“绿色基因”假说(Human"Green-Gene"Hypothesis):核心内容、科学佐证与实践意义 被引量:13
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作者 李树华 康宁 +1 位作者 向鹏天 孟令爽 《中国园林》 CSCD 北大核心 2023年第2期6-12,共7页
首先,对人类“绿色基因”的形成进行探讨,包括人类(动物)与植物共同维持大气中碳氧平衡、人类(动物)与植物互为食物链关系、人体功能中存在植物性功能、绿色是人类眼睛最易看到的颜色、人类血红蛋白的结构相似于叶绿素结构、作为人体呼... 首先,对人类“绿色基因”的形成进行探讨,包括人类(动物)与植物共同维持大气中碳氧平衡、人类(动物)与植物互为食物链关系、人体功能中存在植物性功能、绿色是人类眼睛最易看到的颜色、人类血红蛋白的结构相似于叶绿素结构、作为人体呼吸器官的肺部相似于树木地上部形状(树形)、人类肠道绒毛相似于植物根系毛细根等方面。进而对支持早期人类生活的植物类型与栽培植物诞生进行研究。在此基础上,提出人类“绿色基因”假说及其核心内容,归纳该假说的科学佐证。人类“绿色基因”假说从整体的、发展的思维解释人类与植物关系,奠定了园艺疗法、园林康养、森林康养的坚实基础,并指出接触植物、进行园艺操作与田园劳作是人们实现接地、激发触觉潜在功能的途径。 展开更多
关键词 风景园林 人类与植物关系 人类“绿色基因”假说 绿色脉络 园林康养 园艺疗法
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