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Key Techniques for High-yield and High-efficiency Cultivation of‘Zhouhua 5’Peanut under Film Mulching
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作者 Chaoyang JIA Yake LEI +3 位作者 Jianhang ZHANG Shijie ZHAN Chenwei DENG Jingbin CUI 《Agricultural Biotechnology》 2026年第1期13-15,25,共4页
With the expansion of peanut planting area year by year,film mulching cultivation has become increasingly important in peanut production due to its unique advantages in enhancing both yield per unit area and overall e... With the expansion of peanut planting area year by year,film mulching cultivation has become increasingly important in peanut production due to its unique advantages in enhancing both yield per unit area and overall economic benefits.Based on the varietal characteristics of‘Zhouhua 5’and addressing practical issues in peanut production,this paper summarized key techniques for high-yield and high-efficiency film mulching cultivation of this variety.These techniques cover all critical stages,including land preparation and fertilization,seed preparation,sowing methods,field management,and timely harvesting,providing technical guidance for varietal promotion and peanut production. 展开更多
关键词 PEANUT Zhouhua 5 Film mulching Key technique
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Research on heuristic approximation algorithm of the densest k-subgraph discovery in large-scale dynamic graphs
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作者 HAN Tao TIAN Yuxi +1 位作者 ZHAO Jianwei WANG Senzhang 《Journal of Southeast University(English Edition)》 2026年第1期74-79,共6页
To address the issue that static densest subgraph mining algorithms often exhibit low efficiency when handling large scale dynamic graphs,this paper proposes a heuristic approximation algorithm.The algorithm approxima... To address the issue that static densest subgraph mining algorithms often exhibit low efficiency when handling large scale dynamic graphs,this paper proposes a heuristic approximation algorithm.The algorithm approximates the densest k-subgraphs of the entire graph through four steps:partitioning the large-scale dynamic graph,constructing a partial set of the densest k-subgraphs,heuristically merging the subgraph sets,and finally extracting the densest k-subgraphs.This approach significantly reduces the computational time for large-scale dynamic graphs while simultaneously improving the quality of the resulting subgraphs.This algorithm is applicable to various definitions of“density”and can accommodate diverse requirements on the number of edges.When integrated with existing static densest subgraph detection algorithms,it achieves scalability and computational efficiency.Theoretical analysis demonstrates that the optimal density of the densest k-subgraphs extracted by the proposed algorithm reaches 0.9.To evaluate the performance of the algorithm,experiments were conducted on four billion-scale datasets:Friendster,Orkut,YouTube,and DBLP.The results indicate that the proposed algorithm outperforms static methods in both runtime efficiency and subgraph quality on large-scale dynamic graphs. 展开更多
关键词 the densest k-subgraph FEATURES heuristic approximation algorithm optimal density
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Prospects and potential mechanism of appropriate traditional Chinese medicine techniques for myopia treatment
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作者 Hui-Min Guo Hong-Mei Li Shu-Li Man 《Traditional Medicine Research》 2026年第1期100-114,共15页
Currently,the number of patients with myopia is increasing rapidly across the globe.Traditional Chinese medicine(TCM),with its long history and rich experience,has shown promise in effectively managing and treating th... Currently,the number of patients with myopia is increasing rapidly across the globe.Traditional Chinese medicine(TCM),with its long history and rich experience,has shown promise in effectively managing and treating this condition.Nevertheless,considering the vast amount of research that is currently being conducted,focusing on the utilization of TCM in the management of myopia,there is an urgent requirement for a thorough and comprehensive review.The review would serve to clarify the practical applications of TCM within this specific field,and it would also aim to elucidate the underlying mechanisms that are at play,providing a deeper understanding of how TCM principles can be effectively integrated into modern medical practices.Here,some modern medical pathogenesis of myopia and appropriate TCM techniques studies are summarized in the prevention and treatment of myopia.Further,we discussed the potential mechanisms and the future research directions of TCM against myopia.Identifying these mechanisms is crucial for understanding how TCM can be effectively utilized in this context.The combination of various TCM methods or the combination of traditional Chinese and Western medicine is of great significance for the prevention and control of myopia in the future. 展开更多
关键词 traditional Chinese medicine MYOPIA PATHOGENESIS appropriate TCM techniques
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A Comprehensive Literature Review of AI-Driven Application Mapping and Scheduling Techniques for Network-on-Chip Systems
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作者 Naveed Ahmad Muhammad Kaleem +5 位作者 Mourad Elloumi Muhammad Azhar Mushtaq Ahlem Fatnassi Mohd Fazil Anas Bilal Abdulbasit A.Darem 《Computer Modeling in Engineering & Sciences》 2026年第1期118-155,共38页
Network-on-Chip(NoC)systems are progressively deployed in connecting massively parallel megacore systems in the new computing architecture.As a result,application mapping has become an important aspect of performance ... Network-on-Chip(NoC)systems are progressively deployed in connecting massively parallel megacore systems in the new computing architecture.As a result,application mapping has become an important aspect of performance and scalability,as current trends require the distribution of computation across network nodes/points.In this paper,we survey a large number of mapping and scheduling techniques designed for NoC architectures.This time,we concentrated on 3D systems.We take a systematic literature review approach to analyze existing methods across static,dynamic,hybrid,and machine-learning-based approaches,alongside preliminary AI-based dynamic models in recent works.We classify them into several main aspects covering power-aware mapping,fault tolerance,load-balancing,and adaptive for dynamic workloads.Also,we assess the efficacy of each method against performance parameters,such as latency,throughput,response time,and error rate.Key challenges,including energy efficiency,real-time adaptability,and reinforcement learning integration,are highlighted as well.To the best of our knowledge,this is one of the recent reviews that identifies both traditional and AI-based algorithms for mapping over a modern NoC,and opens research challenges.Finally,we provide directions for future work toward improved adaptability and scalability via lightweight learned models and hierarchical mapping frameworks. 展开更多
关键词 Application mapping mapping techniques NETWORK-ON-CHIP system on chip optimisation
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Impact of Data Processing Techniques on AI Models for Attack-Based Imbalanced and Encrypted Traffic within IoT Environments
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作者 Yeasul Kim Chaeeun Won Hwankuk Kim 《Computers, Materials & Continua》 2026年第1期247-274,共28页
With the increasing emphasis on personal information protection,encryption through security protocols has emerged as a critical requirement in data transmission and reception processes.Nevertheless,IoT ecosystems comp... With the increasing emphasis on personal information protection,encryption through security protocols has emerged as a critical requirement in data transmission and reception processes.Nevertheless,IoT ecosystems comprise heterogeneous networks where outdated systems coexist with the latest devices,spanning a range of devices from non-encrypted ones to fully encrypted ones.Given the limited visibility into payloads in this context,this study investigates AI-based attack detection methods that leverage encrypted traffic metadata,eliminating the need for decryption and minimizing system performance degradation—especially in light of these heterogeneous devices.Using the UNSW-NB15 and CICIoT-2023 dataset,encrypted and unencrypted traffic were categorized according to security protocol,and AI-based intrusion detection experiments were conducted for each traffic type based on metadata.To mitigate the problem of class imbalance,eight different data sampling techniques were applied.The effectiveness of these sampling techniques was then comparatively analyzed using two ensemble models and three Deep Learning(DL)models from various perspectives.The experimental results confirmed that metadata-based attack detection is feasible using only encrypted traffic.In the UNSW-NB15 dataset,the f1-score of encrypted traffic was approximately 0.98,which is 4.3%higher than that of unencrypted traffic(approximately 0.94).In addition,analysis of the encrypted traffic in the CICIoT-2023 dataset using the same method showed a significantly lower f1-score of roughly 0.43,indicating that the quality of the dataset and the preprocessing approach have a substantial impact on detection performance.Furthermore,when data sampling techniques were applied to encrypted traffic,the recall in the UNSWNB15(Encrypted)dataset improved by up to 23.0%,and in the CICIoT-2023(Encrypted)dataset by 20.26%,showing a similar level of improvement.Notably,in CICIoT-2023,f1-score and Receiver Operation Characteristic-Area Under the Curve(ROC-AUC)increased by 59.0%and 55.94%,respectively.These results suggest that data sampling can have a positive effect even in encrypted environments.However,the extent of the improvement may vary depending on data quality,model architecture,and sampling strategy. 展开更多
关键词 Encrypted traffic attack detection data sampling technique AI-based detection IoT environment
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Research on Casing Techniques for Horizontal Drilling in Fractured Strata During Water Conveyance Tunnel Exploration
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作者 Changyou Dai Zijia Ge Shulei Zhang 《Journal of Environmental & Earth Sciences》 2026年第3期154-168,共15页
The most common aspect of water conveyance tunnel construction is the use of horizontal and sub-horizontal exploration drilling of headings of a tunnel to predict geology and groundwater conditions.The instability of ... The most common aspect of water conveyance tunnel construction is the use of horizontal and sub-horizontal exploration drilling of headings of a tunnel to predict geology and groundwater conditions.The instability of boreholes,extreme loss of circulation,and high-head inflow are also common in fractured strata,which often inhibit completion of probe holes and the reliability of coring,packer testing,and grouting tests.Casing,consequently,is a significant enabling technology to stabilize fractured intervals and has a hydraulic isolation under coupled mechanical and hydrogeological disturbances.The review is a synthesis of research and engineering experience on methods of casing to be used in horizontal drilling of fractured rock masses used in the exploration of water conveyance tunnels.The geological and working environment is initially outlined with a focus on fracture-adaptable instability processes and the special goings on of underground drilling,such as the restricted workspace,cuttings difficult to move,and fast movement of the competent and crushed regions.Types of casing systems are then listed,including both standard threaded steel strings and telescopic programs,and more specialized casing system types,including expandable casing,swellable sealing elements,and external casing packers.Special focus is made on the sealing of annulus in horizontal holes,wherein slurry loss,gravity segregation,and non-uniform borehole geometry usually worsen isolation.Lastly,the article suggests adaptive choice of strategy according to real-time drilling reaction,and research priorities,such as tunnel-specific performance measurements,coupled hydro-mechanical modelling,and field trials of sophisticated sealing material and data-driven choice making. 展开更多
关键词 Horizontal Exploration Drilling Fractured Strata Casing techniques Annulus Sealing Water Conveyance Tunnel
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The Application Progress of Traditional Chinese Medicine Nursing Appropriate Techniques in Patients with Insomnia
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作者 Xuling Li 《Journal of Clinical and Nursing Research》 2026年第2期128-135,共8页
This paper elaborates on the concept of Traditional Chinese Medicine(TCM)nursing appropriate techniques,selects techniques including moxibustion,auricular seed pressing,acupoint application,massage and Tuina,Chinese h... This paper elaborates on the concept of Traditional Chinese Medicine(TCM)nursing appropriate techniques,selects techniques including moxibustion,auricular seed pressing,acupoint application,massage and Tuina,Chinese herbal foot bath,five-tone therapy,and aromatherapy,and summarizes the application mechanisms,methods,and clinical effects of these techniques in patients with insomnia.It also analyzes the existing problems in their application and discusses future development and practice directions,aiming to provide references for establishing more standardized and scientific nursing plans for patients with insomnia. 展开更多
关键词 Traditional Chinese medicine nursing INSOMNIA Bu mei(sleeplessness) Appropriate techniques Review
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Key points for the Chen's transpancreatic continuous U-suture technique for pancreaticojejunostomy
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作者 Yan Chen Qi Cheng +4 位作者 Lin Chen Erlei Zhang Shuai Xiang Changhai Li Xiaoping Chen 《Oncology and Translational Medicine》 2026年第1期4-9,共6页
1.Introduction.Pancreaticoduodenectomy is an essential surgical procedure for the treatment of malignant tumors in the pancreatic head,distal common bile duct,and duodenal papilla,and is widely used in clinical practi... 1.Introduction.Pancreaticoduodenectomy is an essential surgical procedure for the treatment of malignant tumors in the pancreatic head,distal common bile duct,and duodenal papilla,and is widely used in clinical practice.One of the primary determinants of surgical success is the durability of the pancreaticojejunal anastomosis. 展开更多
关键词 PANCREATICODUODENECTOMY surgical procedure malignant tumors pancreaticojejunal anastomosis durability surgical success transpancreatic continuous USuture technique
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Analysis of the Preventive Effects of Shoulder Dystocia Midwifery Techniques and Predictive Nursing on Shoulder Dystocia
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作者 Wei Li Aiming Wang 《Journal of Clinical and Nursing Research》 2026年第2期421-428,共8页
Objective: To evaluate the preventive effect of shoulder dystocia midwifery techniques combined with predictive nursing on shoulder dystocia. Methods: A total of 82 high-risk pregnant women with shoulder dystocia admi... Objective: To evaluate the preventive effect of shoulder dystocia midwifery techniques combined with predictive nursing on shoulder dystocia. Methods: A total of 82 high-risk pregnant women with shoulder dystocia admitted for childbirth from January 2022 to January 2025 were selected and equally divided using a random number table. The experimental group received shoulder dystocia midwifery techniques combined with predictive nursing, while the reference group received routine midwifery care. Indicators such as the preventive effect on shoulder dystocia were compared between the two groups. Results: The incidence of shoulder dystocia in the experimental group was lower than that in the reference group, the duration of labor was shorter, the amount of intra-partum bleeding was less, the incidence of adverse delivery outcomes was lower, and the score for fear of childbirth after intervention was lower than that in the reference group (p < 0.05). Conclusion: Implementing shoulder dystocia midwifery techniques combined with predictive nursing for high-risk pregnant women with shoulder dystocia can prevent shoulder dystocia and other adverse delivery outcomes, shorten the duration of labor, reduce intra-partum bleeding, and alleviate pregnant women’s fear of childbirth, demonstrating high nursing value. 展开更多
关键词 Shoulder dystocia midwifery techniques Predictive nursing Shoulder dystocia Preventive effect Adverse delivery outcomes
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Research Advances in Modern Analytical Techniques for Quality Control and Clinical Application of Ganmai Dazao Decoction
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作者 Zihan Zhu 《Journal of Clinical and Nursing Research》 2026年第1期338-344,共7页
Ganmai Dazao Decoction,originating from“Jin Gui Yao Lue”(Synopsis of the Golden Chamber),is a classical prescription for treating visceral agitation.Composed of three medicinal and edible substances-licorice(Gancao)... Ganmai Dazao Decoction,originating from“Jin Gui Yao Lue”(Synopsis of the Golden Chamber),is a classical prescription for treating visceral agitation.Composed of three medicinal and edible substances-licorice(Gancao),wheat(Xiaomai),and jujube(Dazao),it functions to nourish the heart and calm the mind,harmonize the middle burner and regulate Qi,and alleviate urgency and restlessness.As its clinical application has expanded from traditional emotional disorders to neurological,endocrine,and various psychosomatic diseases,establishing a scientifically precise quality control system and deeply elucidating its pharmacodynamic material basis and mechanism of action have become critical tasks.Modern analytical methods,typified by chromatography,spectroscopy,and their hyphenated techniques,with their high sensitivity,high resolution,and powerful substance characterization capabilities,have become the core driving force for standardizing the quality control and modernizing the clinical application research of this formula.This paper systematically reviews the progress of the aforementioned analytical techniques and chemometrics in interpreting the chemical composition,establishing fingerprint profiles,controlling process quality,and researching the pharmacodynamic material basis of Ganmai Dazao Decoction.Furthermore,it discusses integrated approaches combining analytical techniques with pharmacology and clinical medicine to reveal mechanisms of action and explore therapeutic biomarkers.Finally,it provides an outlook on future directions and challenges,including technological integration and innovation,standardization of whole-process quality control systems,and evidence-based research aimed at internationalization. 展开更多
关键词 Ganmai Dazao Decoction Quality control Modern analytical techniques FINGERPRINT Pharmacodynamic material basis Clinical application
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A Comprehensive Review and Algorithmic Analysis of Histogram-Based Contrast Enhancement Techniques for Medical Imaging
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作者 Saira Ali Bhatti Maqbool Khan +4 位作者 Arshad Ahmad Muhammad Shahid Anwar Leila Jamel Aisha M.Mashraqi Wadee Alhalabi 《Computer Modeling in Engineering & Sciences》 2026年第3期37-79,共43页
Medical imaging is essential in modern health care,allowing accurate diagnosis and effective treatment planning.These images,however,often demonstrate low contrast,noise,and brightness distortion that reduce their dia... Medical imaging is essential in modern health care,allowing accurate diagnosis and effective treatment planning.These images,however,often demonstrate low contrast,noise,and brightness distortion that reduce their diagnostic reliability.This review presents a structured and comprehensive analysis of advanced histogram equalization(HE)-based techniques for medical image enhancement.Our review methodology encompasses:(1)classical HE approaches and related limitations in medical domains;(2)adaptive schemes like Adaptive Histogram Equalization(AHE)and Contrast Limited Adaptive Histogrma Equalization(CLAHE)and their advance variants;(3)brightnesspreserving schemes like BBHE and MMBEBHE and related algorithms;(4)dynamic and recursive histogram equalization methods incorporating DHE and RMSHE;(5)fuzzy logic-based enhancement methodologies addressing uncertainty and noise in medical images;and(6)hybrid optimization methodologies through the application of metaheuristic algorithms(World Cup Optimization,Particle Swarm Optimization,Genetic Algorithms,along with histogram-based methodologies.)There is also a comparative discussion given based on contrast improvement,image brightness preservation,noise management,and computational efficiency.Such advancements have better capabilities of improving image quality,which is more important for improved diagnosis and image analysis. 展开更多
关键词 Medical imaging image enhancement techniques histogram equalization contrast enhancement noise reduction brightness preservation diagnostic accuracy
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Synaptic pruning mechanisms and application of emerging imaging techniques in neurological disorders
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作者 Yakang Xing Yi Mo +1 位作者 Qihui Chen Xiao Li 《Neural Regeneration Research》 2026年第5期1698-1714,共17页
Synaptic pruning is a crucial process in synaptic refinement,eliminating unstable synaptic connections in neural circuits.This process is triggered and regulated primarily by spontaneous neural activity and experience... Synaptic pruning is a crucial process in synaptic refinement,eliminating unstable synaptic connections in neural circuits.This process is triggered and regulated primarily by spontaneous neural activity and experience-dependent mechanisms.The pruning process involves multiple molecular signals and a series of regulatory activities governing the“eat me”and“don't eat me”states.Under physiological conditions,the interaction between glial cells and neurons results in the clearance of unnecessary synapses,maintaining normal neural circuit functionality via synaptic pruning.Alterations in genetic and environmental factors can lead to imbalanced synaptic pruning,thus promoting the occurrence and development of autism spectrum disorder,schizophrenia,Alzheimer's disease,and other neurological disorders.In this review,we investigated the molecular mechanisms responsible for synaptic pruning during neural development.We focus on how synaptic pruning can regulate neural circuits and its association with neurological disorders.Furthermore,we discuss the application of emerging optical and imaging technologies to observe synaptic structure and function,as well as their potential for clinical translation.Our aim was to enhance our understanding of synaptic pruning during neural development,including the molecular basis underlying the regulation of synaptic function and the dynamic changes in synaptic density,and to investigate the potential role of these mechanisms in the pathophysiology of neurological diseases,thus providing a theoretical foundation for the treatment of neurological disorders. 展开更多
关键词 CHEMOKINE COMPLEMENT experience-dependent driven synaptic pruning imaging techniques NEUROGLIA signaling pathways synapse elimination synaptic pruning
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Nanjing Yunjin Brocade Weaving Technique
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《China Today》 2026年第1期80-80,共1页
THE Nanjing Yunjin brocade,known for its stunning luster,exquisite patterns,and a wealth of shades,represents the highest level of Chinese brocade craftsmanship.It was the designated textile for the imperial courts of... THE Nanjing Yunjin brocade,known for its stunning luster,exquisite patterns,and a wealth of shades,represents the highest level of Chinese brocade craftsmanship.It was the designated textile for the imperial courts of the Yuan(1206-1368),Ming(1368-1644),and Qing(1616-1911)dynasties,and is still highly regarded to this day. 展开更多
关键词 Nanjing Yunjin Yuan Dynasty Brocade Weaving technique Ming Dynasty Imperial Courts Chinese Brocade nanjing yunjin brocadeknown Qing Dynasty
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The Newly Discovered Pathway for Oxygen Evolution Reaction: In-Situ/Operando Characterization Techniques for Catalyst Development
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作者 Rabia Khalid Muhammad Tahir +2 位作者 Muhammad Umar Pin Fang Yujing Li 《Carbon Energy》 2026年第3期12-40,共29页
Water electrolysis is pivotal for converting renewable energy into clean hydrogen fuel,addressing global energy demand sustainably.However,the development of highly efficient and cost-effective catalysts for the oxyge... Water electrolysis is pivotal for converting renewable energy into clean hydrogen fuel,addressing global energy demand sustainably.However,the development of highly efficient and cost-effective catalysts for the oxygen evolution reaction(OER)remains a significant challenge,particularly at the industrial scale.This report explores a newly discovered pathway,the oxide path mechanism(OPM) for OER-mechanism involving the oxide formation and evolution during the reaction,emphasizing its potential to overcome existing limitations.OPM enables direct O-O coupling without oxygen vacancies,offering superior stability.We detail both classical and innovative in-situ characterization techniques that are central to unraveling the OER mechanism.The advanced in-situ electrochemical techniques,such as inductively coupled plasma mass spectroscopy,X-ray photoelectron spectroscopy,and Mössbauer spectroscopy,coupled with in-situ structural analyses,provide crucial insights into the catalyst surface,the electrode-electrolyte interface and the kinetics of OER.This review provides a systematic analysis integrating classical electrochemical methods with advanced in-situ/operando techniques,specifically focusing on understanding OPM.While numerous studies have examined individual characterization methods,this study systematically integrates traditional electrochemical approaches with in-situ and operando techniques,offering critical insights into their complementary roles in elucidating reaction pathways.The integration of these methodologies provides unprecedented understanding of catalyst behavior under operational conditions,guiding the rational design of next-generation OER catalysts.Furthermore,we discuss essential standardized test toolkits and protocols,such as those for rotating disk electrode and membrane electrode assembly,which are vital for ensuring reproducibility and scalability in OER catalyst research. 展开更多
关键词 in-situ characterization techniques mechanistic understanding OER catalyst operando spectroscopy oxygen evolution reaction(OER) renewable energy water splitting
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In-situ stress solution theory for borehole overcoring technique incorporating time-dependent effect of stress relief and its applications
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作者 Daohong Xia Shengjun Miao +5 位作者 Lianjun Chen Yuan Li Zejing Liu Rongmin Zhang Pengjin Yang Pengcheng Li 《International Journal of Mining Science and Technology》 2026年第1期187-203,共17页
In-situ stress is a key parameter for underground mine design and rock stability analysis.The borehole overcoring technique is widely used for in-situ stress measurement,but the rheological recovery deformation of roc... In-situ stress is a key parameter for underground mine design and rock stability analysis.The borehole overcoring technique is widely used for in-situ stress measurement,but the rheological recovery deformation of rocks after stress relief introduces errors.To improve accuracy,this study proposes an in-situ stress solution theory that incorporates time-dependent stress relief effects.Triaxial stepwise loadingunloading rheological tests on granite and siltstone established quantitative relationships between instantaneous elastic recovery and viscoelastic recovery under different stress levels,confirming their impact on measurement accuracy.By integrating a dual-class elastic deformation recovery model,an improved in-situ stress solution theory was derived.Additionally,accounting for the nonlinear characteristics of rock masses,a determination method for time-dependent nonlinear mechanical parameters was proposed.Based on the CSIRO hollow inclusion strain cell,time-dependent strain correction equations and long-term confining pressure calibration equations were formulated.Finally,the proposed theory was successfully applied at one iron mine(736 m depth)in Xinjiang,China,and one coal mine(510 m depth)in Ningxia,China.Compared to classical theory,the calculated mean stress values showed accuracy improvements of 6.0%and 9.4%,respectively,validating the applicability and reliability of the proposed theory. 展开更多
关键词 In-situ stress solution theory Borehole overcoring technique Time-dependent effect of stress relief Viscoelastic recovery strain of rock In-situ stress measurement
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APPROXIMATION TECHNIQUES FOR APPLICATION OF GENETIC ALGORITHMS TO STRUCTURAL OPTIMIZATION 被引量:1
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作者 金海波 丁运亮 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第2期147-154,共8页
Although the genetic algorithm (GA) has very powerful robustness and fitness, it needs a large size of population and a large number of iterations to reach the optimum result. Especially when GA is used in complex str... Although the genetic algorithm (GA) has very powerful robustness and fitness, it needs a large size of population and a large number of iterations to reach the optimum result. Especially when GA is used in complex structural optimization problems, if the structural reanalysis technique is not adopted, the more the number of finite element analysis (FEA) is, the more the consuming time is. In the conventional structural optimization the number of FEA can be reduced by the structural reanalysis technique based on the approximation techniques and sensitivity analysis. With these techniques, this paper provides a new approximation model-segment approximation model, adopted for the GA application. This segment approximation model can decrease the number of FEA and increase the convergence rate of GA. So it can apparently decrease the computation time of GA. Two examples demonstrate the availability of the new segment approximation model. 展开更多
关键词 approximation techniques segment approximation model genetic algorithms structural optimization sensitivity analysis
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Capacitor self-calibration technique used in time-interleaved successive approximation ADC
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作者 殷勤 戚韬 +1 位作者 吴光林 吴建辉 《Journal of Southeast University(English Edition)》 EI CAS 2006年第2期164-168,共5页
A capacitor self-calibration circuit used in a successive approximation analog-to-digital converter (SA-ADC) is presented. This capacitor self-calibration circuit can calibrate erroneous data and work with the ADC b... A capacitor self-calibration circuit used in a successive approximation analog-to-digital converter (SA-ADC) is presented. This capacitor self-calibration circuit can calibrate erroneous data and work with the ADC by adding an additional clock period. This circuit is used in a 10 bit 32 Msample/s time-interleaved SA- ADC. The chip is implemented with Chart 0. 25 μm 2. 5 V process and totally occupies an area of 1.4 mm× 1.3 mm. After calibration, the simulated signal-to-noise ratio (SNR) is 59. 586 1 dB and the spurious-free dynamic range (SFDR) is 70. 246 dB at 32 MHz. The measured signal-to-noise and distortion ratio (SINAD) is 44. 82 dB and the SFDR is 63. 760 4 dB when the ADC samples a 5.8 MHz sinusoid wave. 展开更多
关键词 capacitor self-calibration analog-to-digital converter successive approximation time-interleaved
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IMPROVED AERODYNAMIC APPROXIMATION MODEL WITH CASE-BASED REASONING TECHNIQUE FOR MDO OF AIRCRAFT
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作者 白振东 刘虎 +1 位作者 柴雪 武哲 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第3期187-193,共7页
To increase the efficiency of the multidisciplinary optimization of aircraft, an aerodynamic approximation model is improved. Based on the study of aerodynamic approximation model constructed by the scaling correction... To increase the efficiency of the multidisciplinary optimization of aircraft, an aerodynamic approximation model is improved. Based on the study of aerodynamic approximation model constructed by the scaling correction model, case-based reasoning technique is introduced to improve the approximation model for optimization. The aircraft case model is constructed by utilizing the plane parameters related to aerodynamic characteristics as attributes of cases, and the formula of case retrieving is improved. Finally, the aerodynamic approximation model for optimization is improved by reusing the correction factors of the most similar aircraft to the current one. The multidisciplinary optimization of a civil aircraft concept is carried out with the improved aerodynamic approximation model. The results demonstrate that the precision and the efficiency of the optimization can be improved by utilizing the improved aerodynamic approximation model with ease-based reasoning technique. 展开更多
关键词 AIRCRAFT aerodynamic approximation model case-based reasoning multidisciplinary optimization(MDO)
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Mismatch Calibration Techniques in Successive Approximation Analog-to-Digital Converters
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作者 王沛 龙善丽 吴建辉 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第9期1369-1374,共6页
Comparator offset cancellation and capacitor self-calibration techniques used in a successive approximation analog-to-digital converter (SA-ADC) are described. The calibration circuit works in parallel with the SAAD... Comparator offset cancellation and capacitor self-calibration techniques used in a successive approximation analog-to-digital converter (SA-ADC) are described. The calibration circuit works in parallel with the SAADC by adding additional calibration clock cycles to pursue high accuracy and low power consumption, and the calibrated resolution can be up to 14bit. This circuit is used in a 10bit 3Msps successive approximation ADC. This chip is realized with an SMIC 0. 18μm 1.8V process and occupies 0.25mm^2 . It consumes 3. 1mW when operating at 1.8MHz. The measured SINAD is 55. 9068dB, SFDR is 64. 5767dB, and THD is - 74. 8889dB when sampling a 320kHz sine wave. 展开更多
关键词 analog-to-digital converter successive approximation self-calibration techniques
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Application of homogenization techniques for inflow transport approximation on light water reactor analysis 被引量:2
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作者 Xiang Xiao Kan Wang +1 位作者 Tong-Rui Yang Yi-Xue Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第1期67-80,共14页
The transport cross-section based on inflow transport approximation can significantly improve the accuracy of light water reactor(LWR)analysis,especially for the treatment of the anisotropic scattering effect.The prev... The transport cross-section based on inflow transport approximation can significantly improve the accuracy of light water reactor(LWR)analysis,especially for the treatment of the anisotropic scattering effect.The previous inflow transport approximation is based on the moderator cross-section and normalized fission source,which is approximated using transport theory.Although the accuracy of reactivity is increased,the P0 flux moment has a large error in the Monte Carlo code.In this study,an improved inflow transport approximation was introduced with homogenization techniques,applying the homogenized cross-section and accurate fission source.The numerical results indicated that the improved inflow transport approximation can increase the P0 flux moment accuracy and maintain the reactivity calculation precision with the previous inflow transport approximation in typical LWR cases.In addition to this investigation,the improved inflow transport approximation is related to the temperature factors.The improved inflow transport approximation is flexible and accurate in the treatment of the anisotropic scattering effect,which can be directly used in the temperature-dependent nuclear data library. 展开更多
关键词 Inflow transport approximation Anisotropic scattering effect Homogenization techniques Light water reactor
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