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A Comparative Study of Optimized-LSTM Models Using Tree-Structured Parzen Estimator for Traffic Flow Forecasting in Intelligent Transportation 被引量:1
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作者 Hamza Murad Khan Anwar Khan +3 位作者 Santos Gracia Villar Luis Alonso DzulLopez Abdulaziz Almaleh Abdullah M.Al-Qahtani 《Computers, Materials & Continua》 2025年第5期3369-3388,共20页
Traffic forecasting with high precision aids Intelligent Transport Systems(ITS)in formulating and optimizing traffic management strategies.The algorithms used for tuning the hyperparameters of the deep learning models... Traffic forecasting with high precision aids Intelligent Transport Systems(ITS)in formulating and optimizing traffic management strategies.The algorithms used for tuning the hyperparameters of the deep learning models often have accurate results at the expense of high computational complexity.To address this problem,this paper uses the Tree-structured Parzen Estimator(TPE)to tune the hyperparameters of the Long Short-term Memory(LSTM)deep learning framework.The Tree-structured Parzen Estimator(TPE)uses a probabilistic approach with an adaptive searching mechanism by classifying the objective function values into good and bad samples.This ensures fast convergence in tuning the hyperparameter values in the deep learning model for performing prediction while still maintaining a certain degree of accuracy.It also overcomes the problem of converging to local optima and avoids timeconsuming random search and,therefore,avoids high computational complexity in prediction accuracy.The proposed scheme first performs data smoothing and normalization on the input data,which is then fed to the input of the TPE for tuning the hyperparameters.The traffic data is then input to the LSTM model with tuned parameters to perform the traffic prediction.The three optimizers:Adaptive Moment Estimation(Adam),Root Mean Square Propagation(RMSProp),and Stochastic Gradient Descend with Momentum(SGDM)are also evaluated for accuracy prediction and the best optimizer is then chosen for final traffic prediction in TPE-LSTM model.Simulation results verify the effectiveness of the proposed model in terms of accuracy of prediction over the benchmark schemes. 展开更多
关键词 Short-term traffic prediction sequential time series prediction TPE tree-structured parzen estimator LSTM hyperparameter tuning hybrid prediction model
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Factors influencing readiness for artificial intelligence: a systematic literature review 被引量:1
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作者 Wajid Ali Abdul Zahid Khan 《Data Science and Management》 2025年第2期224-236,共13页
Public-and private-sector organizations have adopted artificial intelligence(AI)to meet the challenges of the Fourth Industrial Revolution.The successful implementation of AI is a challenging task,and previous researc... Public-and private-sector organizations have adopted artificial intelligence(AI)to meet the challenges of the Fourth Industrial Revolution.The successful implementation of AI is a challenging task,and previous research has advocated the need to explore key readiness before AI implementation.The objective of this study is to identify the AI readiness factors explored by different authors in past research.To achieve this,we conducted a rigorous literature review.The approach used in the systematic literature review is also discussed.A rigorous review of 52 studies from various journals and databases(Science Direct,Springer Link,Institute of Electrical and Electronics Engineers,Emerald,and Google Scholar)identified 23 AI readiness factors.The key factors identified were mainly related to organizational information technology infrastructure,top management support,resource availability,collaborative culture,organizational size,organizational capability,compatibility,data quality,and financial budget,whereas the other 15 were potential factors in AI readiness.All of these factors should be considered before the implementation of AI in any organization.The findings also reflect a high failure rate,including AI readiness factors,which are intended to facilitate AI adoption in organizations and reduce the frequency of failures.These factors will aid management in developing an effective strategy for AI implementation in organizations. 展开更多
关键词 Artificial intelligence READINESS FACTORS
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Progress in the Binding of Chloride Ions in Cement-based Materials
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作者 DU Xixian LI Gang +2 位作者 WANG Aiqin CAO Aoli SUN Jianren 《材料导报》 北大核心 2025年第13期100-113,共14页
Chloride ions(Cl^(-))have been shown to impact the long-lasting nature of reinforced concrete.However,Cl^(-)that are already bound inside the concrete will not lead to the deterioration of the concrete’s characterist... Chloride ions(Cl^(-))have been shown to impact the long-lasting nature of reinforced concrete.However,Cl^(-)that are already bound inside the concrete will not lead to the deterioration of the concrete’s characteristics.The composition of the cement-based material,including the type of cement and auxiliary materials,greatly influences the ability of the material to bind Cl^(-),and varied components result in varying binding beha-vior of the Cl^(-).Simultaneously,the Cl^(-)binding process in concrete is influenced by both the internal and exterior surroundings,as well as the curing practices.These factors impact the hydration process of the cement and the internal pore structure of the concrete.Currently,mathematical theories and molecular dynamics simulations have increasingly been employed as the prevalent methods for examining the binding behaviors of Cl^(-)in concrete.These techniques are extensively utilized for predicting the lifespan and conducting microscopic studies of reinforced concrete in Cl^(-)settings.This work proposes recommendations for future research based on a summary of experimental and simulation investigations on Cl^(-)binding.Which will offer theoretical guidance for studying the binding of Cl^(-)in cement-based materials. 展开更多
关键词 cement-based material chloride binding auxiliary material environment curing practice simulation
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Artificial intelligence for early diagnosis and risk prediction of periodontal-systemic interactions:Clinical utility and future directions
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作者 Neelam Das Keertana R Gade Pavan K Addanki 《World Journal of Methodology》 2025年第4期385-395,共11页
BACKGROUND Artificial intelligence(AI)is transforming healthcare by improving diagnostic accuracy and predictive analytics.Periodontal diseases are recognized as risk factors for systemic conditions,including type 2 d... BACKGROUND Artificial intelligence(AI)is transforming healthcare by improving diagnostic accuracy and predictive analytics.Periodontal diseases are recognized as risk factors for systemic conditions,including type 2 diabetes mellitus,cardiovascular disease,Alzheimer’s disease,polycystic ovary syndrome,thyroid dysfunction,and post-coronavirus disease 2019 complications.These conditions exhibit complex bidirectional interactions,underscoring the importance of early detection and risk stratification.Current diagnostic tools often fail to capture these interactions at an early stage,limiting timely intervention.This study hypothesizes that AI-driven approaches can significantly improve early diagnosis and risk prediction of periodontal-systemic interactions,enhancing clinical outcomes.AIM To evaluate AI’s role in diagnosing and predicting periodontal-systemic interactions in studies from 2010 to 2024.METHODS This systematic review followed PRISMA guidelines(2009)and included peerreviewed articles from PubMed,Scopus,and Embase.Studies with large sample sizes(≥500 participants)were selected,focusing on AI models integrating multiomics data and advanced imaging techniques such as cone beam computed tomography and magnetic resonance imaging.Machine learning models processed structured clinical data,deep learning models combined imaging and clinical data,and natural language processing models extracted insights from clinical notes.RESULTS AI applications significantly enhanced diagnostic and predictive accuracy,reducing diagnostic time by 40%and improving predictive accuracy by 25%in periodontal patients with type 2 diabetes mellitus.Studies with sample sizes of 1000-1500 participants reported diagnostic accuracy improvements up to 92%,with specificity and sensitivity rates of 94%and 90%,respectively.Increasing sample sizes over the years reflected advancements in AI,data collection,and model training,reinforcing model reliability.CONCLUSION AI’s integration of multi-omics and imaging data has transformed early diagnosis and risk prediction in periodontal-systemic interactions,improving clinical outcomes and decision-making. 展开更多
关键词 Artificial intelligence Early diagnosis Risk prediction Periodontal-systemic interactions Type 2 diabetes mellitus Hypertension Pancreatic cancer Artificial intelligence in healthcare Systematic review
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AI-Assisted Flow Field Design for Proton Exchange Membrane Fuel Cells:Progress and Perspective
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作者 Tongxi Zheng Fanyu Meng +6 位作者 Wenxuan Fan Mingxin Liu Dafeng Lu Yang Luan Xunkang Su Guolong Lu Zhenning Liu 《Journal of Bionic Engineering》 2025年第1期47-64,共18页
Bipolar plate is one of the key components of Proton Exchange Membrane Fuel Cell(PEMFC)and a reasonable flow field design for bipolar plate will improve cell performance.Herein,we have reviewed conventional and bionic... Bipolar plate is one of the key components of Proton Exchange Membrane Fuel Cell(PEMFC)and a reasonable flow field design for bipolar plate will improve cell performance.Herein,we have reviewed conventional and bionic flow field designs in recent literature with a focus on bionic flow fields.In particular,the bionic flow fields are summarized into two types:plant-inspired and animal-inspired.The conventional methodology for flow field design takes more time to find the optimum since it is based on experience and trial-and-error methods.In recent years,machine learning has been used to optimize flow field structures of bipolar plates owing to the advantages of excellent prediction and optimization capability.Artificial Intelligence(AI)-assisted flow field design has been summarized into two categories in this review:single-objective optimization and multi-objective optimization.Furthermore,a Threats-Opportunities-Weaknesses-Strengths(TOWS)analysis has been conducted for AI-assisted flow field design.It has been envisioned that AI can afford a powerful tool to solve the complex problem of bionic flow field design and significantly enhance the performance of PEMFC with bionic flow fields. 展开更多
关键词 Proton exchange membrane fuel cell Artificial intelligence BIONIC Flow field Algorithm
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Effect of Nb addition on hole expansion ratio and its precipitation behavior in Ti-microalloyed hot-rolled high-strength steel
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作者 Kang-feng Zhu Wen-jun Wang +2 位作者 Bo Zhang Xin-jun Sun Cai-fu Yang 《Journal of Iron and Steel Research International》 2025年第8期2463-2474,共12页
Increasing the hole expansion ratio is significant for developing high formability parts.Hole expansion tests were carried out on low carbon hot-rolled steel containing 0.11%Ti,0.072%Ti–0.03%Nb and 0.097%Ti–0.059%Nb... Increasing the hole expansion ratio is significant for developing high formability parts.Hole expansion tests were carried out on low carbon hot-rolled steel containing 0.11%Ti,0.072%Ti–0.03%Nb and 0.097%Ti–0.059%Nb,respectively.The effects of microstructure,texture,crack propagation behavior and second phase precipitation behavior on hole expansion ratio were investigated.The precipitation behavior of TiC and(Ti,Nb)C in austenite and ferrite in three groups of steel samples was calculated theoretically.The results showed that the hole expansion ratios of 0.11Ti,0.072Ti–0.03Nb and 0.097Ti–0.059Nb test steels were 51.73%,51.17%and 66.24%following simulated coiling at 600℃,respectively.The microstructure was mainly polygonal ferrite with a small amount of pearlite.The grain refinement of 0.097Ti–0.059Nb test steel and the low texture ratio of{110}//ND improved the hole expansion ratio.The low overall hole expansion ratio was due to the microstructure inhomogeneity.The microstructure uniformity was improved by the quenching and tempering treatment,and the hole expansion ratio of the three test steels was greatly increased.The fastest precipitation temperatures in the austenitic region of 0.11Ti,0.072Ti–0.03Nb and 0.097Ti–0.059Nb test steels were 880,860 and 830℃,while those in the ferrite region were 680,675 and 675℃,respectively.The addition of Nb element increased the volume free energy,so that the critical core size of the nucleation on the dislocation line increased,resulting in the decrease in the fastest precipitation temperature. 展开更多
关键词 Hole expansion ratio Microstructure Mechanical property Second phase MICROALLOYING
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Developing river ethics:Advancing the understanding of water governance principles and promoting the modernization of water governance systems and capabilities
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作者 Yunchang Zhang Bo Liu +2 位作者 Yang Ding Jinyong Zhao Chang Li 《River》 2025年第1期21-28,共8页
River ethics,a significant advancement inspired by Chinese President XI Jinping's ecological civilization thought,embodies the philosophical essence of river governance and represents a legacy of innovation by gen... River ethics,a significant advancement inspired by Chinese President XI Jinping's ecological civilization thought,embodies the philosophical essence of river governance and represents a legacy of innovation by generations of water resources professionals.Rooted in river ecology,it offers a framework for advancing modern water governance systems and capabilities.This paper examines eight dimensions of river ethics to provide actionable recommendations:enhancing knowledge systems on water,rivers,and lakes;addressing critical challenges in water governance to strengthen the foundational role of water authorities in ensuring water security,resource management,ecological sustainability and environmental protection;optimizing water project planning to mitigate ecological impacts;ensuring high standards in the lifecycle management of water projects;refining water diversion strategies for precise scheduling;utilizing ecosystem complexity for river and lake restoration;implementing tiered management of water-related disasters;and driving reforms to modernize water governance systems and mechanisms. 展开更多
关键词 ecosystem restoration high-quality development of water systems river ecology river ethics water governance
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Loosening rocks detection at Draa Sfar deep underground mine in Morocco using infrared thermal imaging and image segmentation models
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作者 Kaoutar Clero Said Ed-Diny +9 位作者 Mohammed Achalhi Mouhamed Cherkaoui Imad El Harraki Sanaa El Fkihi Intissar Benzakour Tarik Soror Said Rziki Hamd Ait Abdelali Hicham Tagemouati François Bourzeix 《Artificial Intelligence in Geosciences》 2025年第1期1-13,共13页
Rockfalls are among the frequent hazards in underground mines worldwide,requiring effective methods for detecting unstable rock blocks to ensure miners’and equipment’s safety.This study proposes a novel approach for... Rockfalls are among the frequent hazards in underground mines worldwide,requiring effective methods for detecting unstable rock blocks to ensure miners’and equipment’s safety.This study proposes a novel approach for identifying potential rockfall zones using infrared thermal imaging and image segmentation techniques.Infrared images of rock blocks were captured at the Draa Sfar deep underground mine in Morocco using the FLUKE TI401 PRO thermal camera.Two segmentation methods were applied to locate the potential unstable areas:the classical thresholding and the K-means clustering model.The results show that while thresholding allows a binary distinction between stable and unstable areas,K-means clustering is more accurate,especially when using multiple clusters to show different risk levels.The close match between the clustering masks of unstable blocks and their corresponding visible light images further validated this.The findings confirm that thermal image segmentation can serve as an alternative method for predicting rockfalls and monitoring geotechnical issues in underground mines.Underground operators worldwide can apply this approach to monitor rock mass stability.However,further research is recommended to enhance these results,particularly through deep learning-based segmentation and object detection models. 展开更多
关键词 Underground mining Image processing K-means clustering Infrared thermal imaging Geotechnical monitoring
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A Review of Research Trends in Public-Private Partnership based on CiteSpace:Bibliometrics and Visualization
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作者 Huijie Jiang Lihong Li +1 位作者 Hang Yin Yuanzhi Wang 《Journal of Architectural Research and Development》 2025年第1期21-45,共25页
Applying the Public-Private Partnership(PPP)model is indispensable in creating new economic growth points in the public service sector.However,there is still a lack of research on mapping the application of the PPP mo... Applying the Public-Private Partnership(PPP)model is indispensable in creating new economic growth points in the public service sector.However,there is still a lack of research on mapping the application of the PPP model in the new era and context.Therefore,based on reviewing the characteristics and development concepts of the PPP model,this paper uses CiteSpace software to analyze the sample authors,journals,and regions in the Scopus database.This paper aims to explore the current development status,research paradigms,and research gap as well as future trends of the PPP model.The results show that(1)The focus of PPP research has shifted from traditional models such as Build-Operate-Transfer(BOT)and Private Finance Initiatives(PFI)to contemporary themes such as risk management,policy analysis,and project governance.Subsequent research(2014-2018)has emphasized the importance of governance and regulatory frameworks to improve PPP outcomes.(2)The growing academic interest in PPP development in China accounts for 28.78%of the total publications.This surge reflects China's rapid economic growth and highlights the interplay between government regulation and private financing.Key research themes include risk management,performance evaluation,contractual flexibility,and financing mechanisms,particularly concerning the BOT model.(3)Effective risk management,relationship dynamics,and innovative financing strategies are key components of a strong PPP knowledge framework.Collaborative risk sharing and strong relationships between public and private entities are key to project success,and strategic financing partnerships are necessary to cope with the complexity of large infrastructure projects. 展开更多
关键词 CITESPACE Public-Private Partnership(PPP) Bibliometrics and visualization
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Effect of tempering temperature on microstructure and mechanical properties of flange forgings for high-pressure hydrogen storage vessels
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作者 Xin-jun Sun Kang-feng Zhu +5 位作者 Hai-dong Jia Bo Zhang Ba Li Wan-bo Dou Xiao-kai Liang Cai-fu Yang 《Journal of Iron and Steel Research International》 2025年第9期2893-2906,共14页
The mechanical properties,microstructure and second phase precipitation behavior of flange forgings for high-pressure hydrogen storage vessels at different tempering temperatures(620–700℃)were studied.The results sh... The mechanical properties,microstructure and second phase precipitation behavior of flange forgings for high-pressure hydrogen storage vessels at different tempering temperatures(620–700℃)were studied.The results showed that when tempered at 620–680°C,the main microstructure of the test steel was tempered sorbite,and the main microstructure of tempered steel changed to martensite at 700℃.At 700℃,the dislocation density increased and some retained austenite existed.With the tempering temperature increasing,the yield strength showed a decreasing trend,the formation of fresh martensite made the tensile strength first decrease and then increase slightly,the impact energy at−40℃increased first and then decreased,and the impact energy at 660℃had the maximum value.The precipitates of MC type were mainly(Mo,V,Ti)C.The test steel had excellent strength and toughness matching at 660℃tempering,the tensile strength at different cross section locations was above 750 MPa,the impact energy was above 200 J at−40℃,and the relative percentage reduction of area(ZH2/ZN2)was above 75%at hydrogen environment of 6.3 MPa. 展开更多
关键词 FORGING Hydrogen storage pressure vessel Tempering temperature MICROSTRUCTURE Mechanical property
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Evaluation of Estimated Ultimate Recovery for Shale Gas InfillWells Considering Inter-Well Crossflow Dynamics
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作者 Cuiping Yuan Sicun Zhong +4 位作者 Yijia Wu Man Chen Ying Wang Yinping Cao Jia Chen 《Fluid Dynamics & Materials Processing》 2025年第7期1689-1710,共22页
Field development practices in many shale gas regions(e.g.,the Changning region)have revealed a persistent issue of suboptimal reserve utilization,particularly in areas where the effective drainage width of production... Field development practices in many shale gas regions(e.g.,the Changning region)have revealed a persistent issue of suboptimal reserve utilization,particularly in areas where the effective drainage width of production wells is less than half the inter-well spacing(typically 400-500 m).To address this,infill drilling has become a widely adopted and effective strategy for enhancing reservoir contact andmobilizing previously untapped reserves.However,this approach has introduced significant inter-well interference,complicating production dynamics and performance evaluation.The two primary challenges hindering efficient deployment of infill wells are:(1)the quantitative assessment of hydraulic and pressure connectivity between infill wells and their associated parent wells,and(2)the accurate estimation of platform-scale Estimated Ultimate Recovery(EUR)following infill implementation.This study presents a novel framework to quantify inter-well connectivity by deriving a material balance equation tailored for shale gas infill well groups,explicitly incorporating gas adsorption and desorption mechanisms.The model simultaneously evaluates formation pressure evolution and crossflow behavior between wells,offering a robust analytical basis for performance prediction.For infill wells intersecting the drainage boundaries of parent wells,EUR is estimated using an analytical model developed for multi-stage hydraulically fractured horizontal wells.Meanwhile,the EUR of the parent wells is obtained by summing their pre-infill EUR with the final inter-well crossflow contribution. 展开更多
关键词 Shale gas infill well well interference EUR
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Research on Wave Energy Harvesting Technology Using a Hybrid Triboelectric Nanogenerator and Electromagnetic Generator
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作者 Jingying Zou Wenzhou Liu +3 位作者 Yaoxuan Han Chenxi Wang Chao Dong Youbo Jia 《Energy Engineering》 2025年第10期4081-4097,共17页
The ocean,as one of Earth’s largest natural resources,covers over 70% of the planet’s surface and holds vast water energy potential.Building on this context,this study designs a hybrid generator(WWR-TENG)that integr... The ocean,as one of Earth’s largest natural resources,covers over 70% of the planet’s surface and holds vast water energy potential.Building on this context,this study designs a hybrid generator(WWR-TENG)that integrates a triboelectric nanogenerator(TENG)and an electromagnetic generator(EMG).TENG is a new technology that can capture mechanical energy from the environment and convert it into electrical energy,and is particularly suitable for common natural or man-made power sources such as human movement,wind power,and water flow.EMG is a device that converts mechanical energy into electrical energy through the principle of electromagnetic induction and can usually provide stable power output.The composite design leverages the complementary advantages of both technologies to efficiently capture and convert marine wave energy.By combining the TENG’s high energy conversion efficiency,lowcost,lightweight structure,and simple designwith the EMG’s capabilities,the systemprovides a sustainable solution for marine energy development.Experimental results demonstrate that at a rotational speed of 3.0 r/s,the TENG component of the WWR-TENG achieves an open-circuit voltage of approximately 280 V and a shortcircuit current of 20μA.At the same time,the EMG unit exhibits an open-circuit voltage of 14 V and a short-circuit current of 14 mA.Furthermore,when integrated with a power management circuit,the WWR-TENG charges a 680μF capacitor to 3 V within 10 s at a rotational speed of 3.0 r/s.A simulated wave environment platform was established,enabling the WWR-TENG to maintain the thermo-hygrometer in normal operation under simulated wave conditions.These findings validate the hybrid system’s effectiveness in harnessing and storingwave energy,highlighting its potential for practical marine energy applications. 展开更多
关键词 Wave energy triboelectric nanogenerator electromagnetic generator energy harvesting hybrid nanogenerator
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The integration of microelectronic and photonic circuits on a single silicon chip for high-speed and low-power optoelectronic technology
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作者 Rajeev Gupta Ajay Kumar +17 位作者 Manoj Kumar Rajesh Singh Anita Gehlot Purnendu Shekhar Pandey Neha Yadav Kailash Pandey Ashish Yadav Neha Gupta Ranjeet Brajpuriya Shalendra Kumar Ajay Singh Verma Tanuj Kumar Yongling Wu Zheng Hongyu Abhijit Biswas Ajay Mittal Aniruddha Mondal Romanov Oleksandr Ivanovich 《Nano Materials Science》 2025年第3期305-315,共11页
The combining microelectronic devices and associated technologies onto a single silicon chip poses a substantial challenge.However,in recent years,the area of silicon photonics has experienced remarkable advancements ... The combining microelectronic devices and associated technologies onto a single silicon chip poses a substantial challenge.However,in recent years,the area of silicon photonics has experienced remarkable advancements and notable leaps in performance.The performance of silicon on insulator(SOI)based photonic devices,such as fast silicon optical modulators,photonic transceivers,optical filters,etc.,have been discussed.This would be a step forward in creating standalone silicon photonic devices,strengthening the possibility of single on-chip nanophotonic integrated circuits.Suppose an integrated silicon photonic chip is designed and fabricated.In that case,it might drastically modify these combined photonic component costs,power consumption,and size,bringing substantial,perhaps revolutionary,changes to the next-generation communications sector.Yet,the monolithic integration of photonic and electrical circuitry is a significant technological difficulty.A complicated set of factors must be carefully considered to determine which application will have the best chance of success employing silicon-based integrated product solutions.The processing limitations connected to the current process flow,the process generation(sometimes referred to as lithography node generation),and packaging requirements are a few of these factors to consider.This review highlights recent developments in integrated silicon photonic devices and their proven applications,including but not limited to photonic waveguides,photonic amplifiers and filters,onchip photonic transceivers,and the state-of-the-art of silicon photonic in multidimensional quantum systems.The investigated devices aim to expedite the transfer of silicon photonics from academia to industry by opening the next phase in on-chip silicon photonics and enabling the application of silicon photonic-based devices in various optical systems. 展开更多
关键词 Microelectronic PHOTONICS Silicon chip Optical modulators Photonic transceivers Optical filters
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Behind-plate overpressure effect of steel-encased reactive material projectile impacting thin aluminum plate 被引量:7
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作者 Qing-bo Yu Jia-hao Zhang +2 位作者 Hong-wei Zhao Yan-wen Xiao Hai-fu Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第5期723-734,共12页
Ballistic impact and sealed chamber tests were performed on the steel-encased reactive material projectile(SERMP)to understand its behind-plate overpressure effect when impacting the thin aluminum plates.The reactive ... Ballistic impact and sealed chamber tests were performed on the steel-encased reactive material projectile(SERMP)to understand its behind-plate overpressure effect when impacting the thin aluminum plates.The reactive material encased with a 1.5 mm thick 30CrMnSiNi2A steel shell was launched onto the initially sealed test chamber with a 3 mm thick 2024-T3 thin aluminum cover plate.Moreover,the overpressure signals in the test chamber were recorded by pressure sensors.The experimental results indicate an unusual behind-plate overpressure effect:as the density of the projectile increases from 6.43 g/cm^(3) to 7.58 g/cm^(3) by increasing the content of tungsten powder,although its total chemical energy decreases,it produces a higher behind-target overpressure at a lower impact velocity.A theoretical model is proposed to predict the reaction length of reactive material inside the projectile based on one-dimensional shock wave theory to understand this unexpected result.In addition,the deviation between the actual energy release and the theoretical calculation results,also the variation of overpressure rise time are analyzed and discussed.As the analyses show,when the SERMP successfully penetrates the cover plate,an increasing density of the reactive material inside the projectile always means that the delaying rarefaction wave effect,an increase of its internal pressure and strain rate levels.These factors lead to the increase of the overpressure limit velocity and reaction extent of the reactive material,while the overpressure rise time decreases. 展开更多
关键词 Reactive materials Steel-encased reactive material projectile Over-pressure effect Overpressure limit velocity Energy release
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Penalty model for delay of bidding section construction period in South-to-North Water Diversion Eastern Route Project from perspective of programs 被引量:2
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作者 Jing-chun FENG Ya-fang REN +2 位作者 Zhong-nan DUAN Zhan-jun LIU Hai-yang LI 《Water Science and Engineering》 EI CAS 2012年第3期350-360,共11页
According to the multi-project and program management theory, this paper analyzes the program generation principle and establishes a program based on progress goals. On the basis of the present situation of calculatio... According to the multi-project and program management theory, this paper analyzes the program generation principle and establishes a program based on progress goals. On the basis of the present situation of calculation of penalty for delay of the bidding section construction period with the critical path method, we studied the effects of contractor-induced delay of the bidding section construction period in detail, including the effects on the construction period of the bidding section itself, the earliest start times of the next bidding section and other subsequent bidding sections, and the construction period of the program, and then constructed a penalty model for delay of the bidding section construction period from the perspective of programs. Using the penalty model, we conducted a practical analysis of penalty for delay of the construction period of the Baoying station program in the South-to-North Water Diversion Project. The model can help determine the amount of penalty for delay of the construction period in bidding sections scientifically and reasonably, 展开更多
关键词 program establishment program management bidding section construction period critical path method (CPM) penaly model South-to-North Water Diversion Project
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Risk Management: A New Project Management Perspective 被引量:2
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作者 Pasis Mselle Jacob Kashiwagi +1 位作者 Dean Kashiwagi Aderemi Adeyemi 《Journal of Civil Engineering and Architecture》 2011年第6期505-512,共8页
Risk management in Botswana has been very ineffective at assisting projects to be on time, on budget, and meeting client's/buyer's expectations. Traditional risk management attempts to manage, control, and direct a ... Risk management in Botswana has been very ineffective at assisting projects to be on time, on budget, and meeting client's/buyer's expectations. Traditional risk management attempts to manage, control, and direct a project through various phases, from planning and design, through procurement, and to construction. However, the risk management in Botswana seems to be either not implemented or not successful. The project performance in Botswana has a poor performance record. The researchers are attempting to identify why the traditional project/risk management is not working. In analyzing the problem in Botswana, the researchers discovered that the traditional risk management model was theoretically unsound, and designed a new project and risk model, with an entirely different approach to risk. The new model is an outgrowth of the highly successful Performance Information Procurement System (PIPS) and the Information Measurement Theory (IMT)/Kashiwagi Solution Model (KSM) concepts. The approach has been presented to some Botswana clients and academics and has received a favorable response. The development of the new risk model will lead to a huge change in the paradigm for delivering projects in Botswana. The theoretical development of the new risk model is ongoing at the University of Botswana as a part of a doctoral dissertation. 展开更多
关键词 Risk management Botswana projects new leadership based PM model.
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The Hong Kong-Zhuhai-Macao Island and Tunnel Project 被引量:9
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作者 Ming Lin Wei Lin 《Engineering》 SCIE EI 2017年第6期783-784,共2页
The Hong Kong-Zhuhai-Macao (HZM) Bridge is located at the Pearl River estuary and has a total length of 55 km. The HZM Bridge's main navigational crossing is by way of two 100 000 m2 artificial islands and a 6.7 km... The Hong Kong-Zhuhai-Macao (HZM) Bridge is located at the Pearl River estuary and has a total length of 55 km. The HZM Bridge's main navigational crossing is by way of two 100 000 m2 artificial islands and a 6.7 km long undersea tunnel, which are the link's most critical parts. 展开更多
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Building New Bridges of International Friendship and Making New Achievements for the Belt and Road——A factual report of foreign aid projects of Beijing Xingyou Engineering Project Management Co., Ltd.
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作者 Ren Yuan Wang Weiyu +3 位作者 Duan Hongliang Hu Shengpo Yao Junmin Zhao Shenggang 《China Oil & Gas》 CAS 2018年第5期24-28,共5页
At 09:15 local time on May 13,2018 in the Republic of Mozambique,Li Zhanshu,a member of the Standing Committee of the Political Bureau of the CPC Central Committee and Chairman of the Standing Committee of the Nationa... At 09:15 local time on May 13,2018 in the Republic of Mozambique,Li Zhanshu,a member of the Standing Committee of the Political Bureau of the CPC Central Committee and Chairman of the Standing Committee of the National People's Congress (NPC),and Veronica Macamo,Speaker of the Republic of Mozambique,attended the founding ceremony of the Chinese aid project for the Confucius Institute and Media Arts Institute in Mozambique. 展开更多
关键词 Mozambique Li Zhanshu the CPC Central
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Analysis of Winter Concrete Construction in Water Conservation Project
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作者 Sun Wenzhong 《Journal of Architectural Research and Development》 2018年第3期6-10,共5页
The construction of water conservancy projects should commence during optimal atmospheric conditions and non-flood period to ensure completion before the flood season begin in summer.In most areas of Northern China,th... The construction of water conservancy projects should commence during optimal atmospheric conditions and non-flood period to ensure completion before the flood season begin in summer.In most areas of Northern China,the temperature during winter remain at lower level,in which environmental factors play the most important role in the construction of water conservancy projects.In particular,low temperature directly affects the strength of concrete and delays its solidification,this highly affects the quality and progress of concrete construction.In order to overcome this barrier,better planning,for reasonable and effective construction techniques and targeted control measures should be adopted to reduce the adverse effects of low temperature to assure a strong and safe architecture. 展开更多
关键词 WATER conservancy PROJECTS CONCRETE WINTER CONSTRUCTION
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Is the Culture or Unstable Procurement System Causing Nonperforming Projects?
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作者 Dean Kashiwagi Jacob Kashiwagi +1 位作者 Pasis Mselle Aderemi Adeyemi 《Journal of Civil Engineering and Architecture》 2011年第5期389-401,共13页
A research group at the University of Botswana has been investigating how culture and construction delivery system stability affect the Botswana construction industry performance. The government of Botswana is attempt... A research group at the University of Botswana has been investigating how culture and construction delivery system stability affect the Botswana construction industry performance. The government of Botswana is attempting to increase the construction performance and sustainability of the Botswana construction industry in an environment of local contractors who do not seem to have the expertise and experience. Currently, the Botswana industry is heavily dependent on foreign contractors. The researchers are trying to identify if the problem is the underdeveloped industry and Botswana culture, or potentially the combination of culture and unstable delivery system, and can a stable delivery system raise the performance of Botswana contractors. The two potential areas of interest are the country culture, and the project delivery/management model. The authors are using deductive logic, logical and simplistic models, and dominant or extreme information to minimizing the need to get into a long drawn out study of details which may be difficult to obtain and not necessarily solve the issue. The objective of the paper is to identify the best method to increase the performance of the construction industry, addressing both the cultural and delivery system problems. The preliminary measurement of the success of the solution is the acceptance of the concepts by major users in Botswana. This paper will propose the potential solution, which will be tested starting January 2011. If this solution is valid, it has a tremendous potential in underdeveloped countries. 展开更多
关键词 CULTURE project management Botswana.
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