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An Innovative Soft Design Science Methodology for Improving Development of a Secure Information System in Tanzania Using Multi-Layered Approach 被引量:2
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作者 Maduhu Mshangi Edephonce Ngemera Nfuka Camilius Sanga 《Journal of Information Security》 2017年第3期141-165,共25页
This paper presents an innovative Soft Design Science Methodology for improving information systems security using multi-layered security approach. The study applied Soft Design Science Methodology to address the prob... This paper presents an innovative Soft Design Science Methodology for improving information systems security using multi-layered security approach. The study applied Soft Design Science Methodology to address the problematic situation on how information systems security can be improved. In addition, Soft Design Science Methodology was compounded with mixed research methodology. This holistic approach helped for research methodology triangulation. The study assessed security requirements and developed a framework for improving information systems security. The study carried out maturity level assessment to determine security status quo in the education sector in Tanzania. The study identified security requirements gap (IT security controls, IT security measures) using ISO/IEC 21827: Systems Security Engineering-Capability Maturity Model (SSE-CMM) with a rating scale of 0 - 5. The results of this study show that maturity level across security domain is 0.44 out of 5. The finding shows that the implementation of IT security controls and security measures for ensuring security goals are lacking or conducted in ad-hoc. Thus, for improving the security of information systems, organisations should implement security controls and security measures in each security domain (multi-layer security). This research provides a framework for enhancing information systems security during capturing, processing, storage and transmission of information. This research has several practical contributions. Firstly, it contributes to the body of knowledge of information systems security by providing a set of security requirements for ensuring information systems security. Secondly, it contributes empirical evidence on how information systems security can be improved. Thirdly, it contributes on the applicability of Soft Design Science Methodology on addressing the problematic situation in information systems security. The research findings can be used by decision makers and lawmakers to improve existing cyber security laws, and enact laws for data privacy and sharing of open data. 展开更多
关键词 SOFT DESIGN SCIENCE Information SYSTEMS Security DESIGN SCIENCE Research SOFT SYSTEMS METHODOLOGY multi-layered approach
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General analytical solutions for one-dimensional diffusion of degradable organic contaminant in the multi-layered media containing geomembranes
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作者 JIANG Wen-hao GE Shang-qi LI Jiang-shan 《Journal of Central South University》 2025年第10期3895-3910,共16页
In practical engineering construction,multi-layered barriers containing geomembranes are extensively applied to retard the migration of pollutants.However,the associated analytical theory on pollutants diffusion still... In practical engineering construction,multi-layered barriers containing geomembranes are extensively applied to retard the migration of pollutants.However,the associated analytical theory on pollutants diffusion still needs to be further improved.In this work,general analytical solutions are derived for one-dimensional diffusion of degradable organic contaminant(DOC)in the multi-layered media containing geomembranes under a time-varying concentration boundary condition,where the variable substitution and separated variable approaches are employed.These analytical solutions with clear expressions can be used not only to study the diffusion behaviors of DOC in bottom and vertical composite barrier systems,but also to verify other complex numerical models.The proposed general analytical solutions are then fully validated via three comparative analyses,including comparisons with the experimental measurements,an existing analytical solution,and a finite-difference solution.Ultimately,the influences of different factors on the composite cutoff wall’s(CCW,which consists of two soil-bentonite layers and a geomembrane)service performance are investigated through a composite vertical barrier system as the application example.The findings obtained from this investigation can provide scientific guidance for the barrier performance evaluation and the engineering design of CCWs.This application example also exhibits the necessity and effectiveness of the developed analytical solutions. 展开更多
关键词 general analytical solutions degradable organic contaminant diffusion behavior multi-layered media containing geomembranes composite barrier system
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An improved model for predicting thermal contact resistance at multi-layered rock interface
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作者 WEN Min-jie XIE Jia-hao +4 位作者 LI Li-chen TIAN Yi EL NAGGAR M.Hesham MEI Guo-xiong WU Wen-bing 《Journal of Central South University》 2025年第1期229-243,共15页
This study proposes a general imperfect thermal contact model to predict the thermal contact resistance at the interface among multi-layered composite structures.Based on the Green-Lindsay(GL)thermoelastic theory,semi... This study proposes a general imperfect thermal contact model to predict the thermal contact resistance at the interface among multi-layered composite structures.Based on the Green-Lindsay(GL)thermoelastic theory,semi analytical solutions of temperature increment and displacement of multi-layered composite structures are obtained by using the Laplace transform method,upon which the effects of thermal resistance coefficient,partition coefficient,thermal conductivity ratio and heat capacity ratio on the responses are studied.The results show that the generalized imperfect thermal contact model can realistically describe the imperfect thermal contact problem.Accordingly,it may degenerate into other thermal contact models by adjusting the thermal resistance coefficient and partition coefficient. 展开更多
关键词 multi-layered structures general thermal contact model thermal contact resistance GL thermoelastic theory Laplace transform
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Intelligent Parameter Decision-Making and Multi-objective Prediction for Multi-layer and Multi-pass LDED Process
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作者 Li Yaguan Nie Zhenguo +2 位作者 Li Huilin Wang Tao Huang Qingxue 《稀有金属材料与工程》 北大核心 2026年第1期47-58,共12页
The key parameters that characterize the morphological quality of multi-layer and multi-pass metal laser deposited parts are the surface roughness and the error between the actual printing height and the theoretical m... The key parameters that characterize the morphological quality of multi-layer and multi-pass metal laser deposited parts are the surface roughness and the error between the actual printing height and the theoretical model height.The Taguchi method was employed to establish the correlations between process parameter combinations and multi-objective characterization of metal deposition morphology(height error and roughness).Results show that using the signal-to-noise ratio and grey relational analysis,the optimal parameter combination for multi-layer and multi-pass deposition is determined as follows:laser power of 800 W,powder feeding rate of 0.3 r/min,step distance of 1.6 mm,and scanning speed of 20 mm/s.Subsequently,a Genetic Bayesian-back propagation(GB-BP)network is constructed to predict multi-objective responses.Compared with the traditional back propagation network,the GB-back propagation network improves the prediction accuracy of height error and surface roughness by 43.14%and 71.43%,respectively.This network can accurately predict the multi-objective characterization of morphological quality of multi-layer and multi-pass metal deposited parts. 展开更多
关键词 multi-layer and multi-pass laser cladding Taguchi method grey relational analysis GB-BP network
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Comparing trans-oral endoscopic thyroidectomy vestibular approach and trans-areolar approaches regarding postoperative infections and swallowing difficulty
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作者 Hyder Mirghani 《World Journal of Clinical Cases》 2026年第1期21-27,共7页
BACKGROUND Due to the increasing rate of thyroid nodules diagnosis,and the desire to avoid the unsightly cervical scar,remote thyroidectomies were invented and are increasingly performed.Transoral endoscopic thyroidec... BACKGROUND Due to the increasing rate of thyroid nodules diagnosis,and the desire to avoid the unsightly cervical scar,remote thyroidectomies were invented and are increasingly performed.Transoral endoscopic thyroidectomy vestibular approach and trans-areolar approaches(TAA)are the two most commonly used remote approaches.No previous meta-analysis has compared postoperative infections and swallowing difficulties among the two procedures.AIM To compared the same among patients undergoing lobectomy for unilateral thyroid carcinoma/benign thyroid nodule.METHODS We searched PubMed MEDLINE,Google Scholar,and Cochrane Library from the date of the first published article up to August 2025.The term used were transoral thyroidectomy vestibular approach,trans areolar thyroidectomy,scarless thyroidectomy,remote thyroidectomy,infections,postoperative,inflammation,dysphagia,and swallowing difficulties.We identified 130 studies,of them,30 full texts were screened and only six studies were included in the final meta-analysis.RESULTS Postoperative infections were not different between the two approaches,odd ratio=1.33,95%confidence interval:0.50-3.53,theχ2 was 1.92 and the P-value for overall effect of 0.57.Similarly,transient swallowing difficulty was not different between the two forms of surgery,with odd ratio=0.91,95%confidence interval:0.35-2.40;theχ2 was 1.32,and the P-value for overall effect of 0.85.CONCLUSION No significant statistical differences were evident between trans-oral endoscopic Mirghani H.Infections and swallowing difficulty in scarless thyroidectomy WJCC https://www.wjgnet.com 2 January 6,2026 Volume 14 Issue 1 thyroidectomy vestibular approach and trans-areolar approach regarding postoperative infection and transient swallowing difficulties.Further longer randomized trials are needed. 展开更多
关键词 Trans-oral endoscopic thyroidectomy vestibular approach Trans-areolar approaches Postoperative Infections swallowing difficulty
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Modeling and Vulnerability Analysis of Multi-layer Urban Electric-transportation Interdependent Networks Under Extreme Events
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作者 Gengming Liu Wenxia Liu Qingxin Shi 《CSEE Journal of Power and Energy Systems》 2026年第1期466-480,共15页
The increasing electrification of urban transportation,i.e.,subways and electric vehicles(EV),brings more interactions between the power system and transportation system and further results in fault propagation across... The increasing electrification of urban transportation,i.e.,subways and electric vehicles(EV),brings more interactions between the power system and transportation system and further results in fault propagation across them.To analyze vulnerability of the coupling system under extreme events,this paper establishes a multi-layer urban electric-transportation interdependent network(ETIN)model.First,a weighted coupled metro-road traffic network(CTN)model and network path planning approach are proposed.A prospect theory-based failure load redistribution(FLR)method is further established to account for uncertainty of TN link capacity affected by power supply.Second,topology and emergency control strategy of power network(PN)are modeled,followed by formulation of multi-layer ETIN model.In particular,the inter-layer fault propagation from PN to TN is modeled based on power supply correlation strength,while from TN to PN is modeled based on traffic flow.A few indexes are then defined to quantify vulnerability of ETIN under deliberate attack.Finally,the proposed method is verified on an electric-transportation system to show influence of fault propagations within ETIN on its vulnerability under extreme events. 展开更多
关键词 Electric-traffic interdependent system metro-road traffic coupled network multi-layer interdependent network vulnerability analysis
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Approach angle constrained and varying speed cooperative guidance against maneuvering targets
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作者 Xiangjun Ding Jianan Wang +1 位作者 Junhui Liu Jiayuan Shan 《Defence Technology(防务技术)》 2026年第3期56-70,共15页
This paper addresses the three-dimensional(3-D)approach angle constrained cooperative guidance problem for speed-varying missiles against maneuvering targets.First,the guidance problem is formulated in a relative refe... This paper addresses the three-dimensional(3-D)approach angle constrained cooperative guidance problem for speed-varying missiles against maneuvering targets.First,the guidance problem is formulated in a relative reference frame and a virtual control input is selected.Then,the cooperative guidance law is designed on the basis of a prediction-correction framework.The time-to-go under the baseline command is estimated by an efficient prediction method with a realistic aerodynamic model and a biased command is developed by utilizing the time-to-go predictions for synchronizing different missiles'impact times.The design of the biased command is decoupled into the individual design of its direction and magnitude.It is proved that the designed cooperative guidance law can make the time-to-go consensus error converge to zero before interception.Finally,the designed guidance law is validated through a series of numerical simulations. 展开更多
关键词 Cooperative guidance Maneuvering target Time-varying speed approach angle constraint
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Microstructure and properties of Cu-Ni-Co-Si alloy designed by cluster formula approach
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作者 Shi-fang LI Zhu XIAO +3 位作者 Xiang-peng MENG Zhou LI Yan-lin JIA Yan-bin JIANG 《Transactions of Nonferrous Metals Society of China》 2026年第3期872-886,共15页
A Cu-1.9Ni-1.9Co-0.9Si(mass fraction,%)alloy with high strength and electrical conductivity was designed by cluster formula approach.The microstructure evolution of the alloy during thermomechanical treatment was syst... A Cu-1.9Ni-1.9Co-0.9Si(mass fraction,%)alloy with high strength and electrical conductivity was designed by cluster formula approach.The microstructure evolution of the alloy during thermomechanical treatment was systematically investigated.The strengthening mechanism and electrical conductivity of the alloy were discussed in detail.The optimal thermomechanical treatment process was as follows:solid solution→80%cold rolling→(450℃,4 h)aging→50%cold rolling→(400℃,4 h)aging.The designed alloy achieved excellent comprehensive properties with a microhardness of HV 260,a yield strength of 843 MPa,a tensile strength of 884 MPa,and an electrical conductivity of 42.6%(IACS).Compared to direct aging treatment,the designed alloy subjected to multi-stage thermomechanical treatment had refined grains,high density of dislocations,and accelerated of precipitation of(Ni,Co)_(2)Si precipitates.High strength was mainly attributed to the combined effect of dislocation strengthening,work hardening and sub-grain strengthening,while good electrical conductivity was maintained through the precipitation of the large number of nanoparticles. 展开更多
关键词 Cu-Ni-Co-Si alloys cluster formula approach thermomechanical treatment MICROSTRUCTURE strengthening mechanism
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The application of multi-combinatorial approach in sensitivity improvement of lipid photoacoustic imaging
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作者 Yi Tan Dongjian Wu +4 位作者 Xiatian Wang Chengbo Liu Mingjian Sun Xiaojing Gong Zhihua Xie 《Journal of Innovative Optical Health Sciences》 2026年第1期96-109,共14页
The photoacoustic imaging of lipid is intrinsically constrained by the feeble nature of endogenous lipid signals,posing a persistent sensitivity challenge that demands innovative solutions.Although adopting high-effic... The photoacoustic imaging of lipid is intrinsically constrained by the feeble nature of endogenous lipid signals,posing a persistent sensitivity challenge that demands innovative solutions.Although adopting high-efficiency excitation and detection elements may improve the imaging sensitivity to a certain extent,the application of the elements is inevitably subject to various limitations in practical applications,particularly during in vivo imaging and endoscopic imaging.In this study,we propose a multi-combinatorial approach to enhance the sensitivity of lipid photoacoustic imaging.The approach involves wavelet transform processing of one-dimensional A-line signals,gradient-based denoising of two-dimensional B-scan images,and finally,threedimensional spatial weighted averaging of the data processed by the previous two steps.This method not only significantly improves the signal-to-noise ratio(SNR)in distinguished feature regions of the image by around 10 dB,but also efficiently extracts weak signals with no distinct features in the original image.After processing with this method,the images acquired under single scanning were compared with those obtained under multiple scanning.The results showed highly consistent image features,with the structural similarity index increasing from 0.2 to 0.8,confirming the accuracy and reliability of the multi-combinatorial approach. 展开更多
关键词 Multi-combinatorial approach extraction of weak signals imaging sensitivity photoacoustic lipid imaging
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Optimal pricing approaches for data markets in market-operated data exchanges
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作者 Yangming Lyu Linyi Qian +2 位作者 Zhixin Yang Jing Yao Xiaochen Zuo 《Statistical Theory and Related Fields》 2026年第1期23-45,共23页
This work contributes to the theoretical foundation for pricing in data markets and offers practical insights for managing digital data exchanges in the era of big data.We propose a structured pricing model for data e... This work contributes to the theoretical foundation for pricing in data markets and offers practical insights for managing digital data exchanges in the era of big data.We propose a structured pricing model for data exchanges transitioning from quasi-public to marketoriented operations.To address the complex dynamics among data exchanges,suppliers,and consumers,the authors develop a threestage Stackelberg game framework.In this model,the data exchange acts as a leader setting transaction commission rates,suppliers are intermediate leaders determining unit prices,and consumers are followers making purchasing decisions.Two pricing strategies are examined:the Independent Pricing Approach(IPA)and the novel Perfectly Competitive Pricing Approach(PCPA),which accounts for competition among data providers.Using backward induction,the study derives subgame-perfect equilibria and proves the existence and uniqueness of Stackelberg equilibria under both approaches.Extensive numerical simulations are carried out in the model,demonstrating that PCPA enhances data demander utility,encourages supplier competition,increases transaction volume,and improves the overall profitability and sustainability of data exchanges.Social welfare analysis further confirms PCPA’s superiority in promoting efficient and fair data markets. 展开更多
关键词 Data exchange data market digital economy perfectly competitive pricing approach Stackelberg game
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SSA*-PDWA:A Hierarchical Path Planning Framework with Enhanced A*Algorithm and Dynamic Window Approach for Mobile Robots
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作者 Lishu Qin Yu Gao Xinyuan Lu 《Computers, Materials & Continua》 2026年第4期2069-2094,共26页
With the rapid development of intelligent navigation technology,efficient and safe path planning for mobile robots has become a core requirement.To address the challenges of complex dynamic environments,this paper pro... With the rapid development of intelligent navigation technology,efficient and safe path planning for mobile robots has become a core requirement.To address the challenges of complex dynamic environments,this paper proposes an intelligent path planning framework based on grid map modeling.First,an improved Safe and Smooth A*(SSA*)algorithm is employed for global path planning.By incorporating obstacle expansion and cornerpoint optimization,the proposed SSA*enhances the safety and smoothness of the planned path.Then,a Partitioned Dynamic Window Approach(PDWA)is integrated for local planning,which is triggered when dynamic or sudden static obstacles appear,enabling real-time obstacle avoidance and path adjustment.A unified objective function is constructed,considering path length,safety,and smoothness comprehensively.Multiple simulation experiments are conducted on typical port grid maps.The results demonstrate that the improved SSA*significantly reduces the number of expanded nodes and computation time in static environmentswhile generating smoother and safer paths.Meanwhile,the PDWA exhibits strong real-time performance and robustness in dynamic scenarios,achieving shorter paths and lower planning times compared to other graph search algorithms.The proposedmethodmaintains stable performance across maps of different scales and various port scenarios,verifying its practicality and potential for wider application. 展开更多
关键词 Dynamic window approach improved A*algorithm dynamic path planning trajectory optimization
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Adaptive event-triggered decentralized control for nonlinear interconnected large-scale systems with actuator failures:a fully actuated system approach
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作者 Yueyao Ye Yanan Qi +2 位作者 Yiyu Feng Xiaofeng Xu Xianfu Zhang 《Control Theory and Technology》 2026年第1期82-95,共14页
This study develops an event-triggered control strategy utilizing the fully actuated system approach for nonlinear interconnected large-scale systems containing actuator failures.First,to reduce the complexity of the ... This study develops an event-triggered control strategy utilizing the fully actuated system approach for nonlinear interconnected large-scale systems containing actuator failures.First,to reduce the complexity of the design process,we transform the studied system into the form of a fully actuated system through a state transformation.Then,to address the unknown nonlinear functions and actuator fault parameters,we employ neural networks and adaptive estimation techniques,respectively.Moreover,to reduce the control cost and improve the control efficiency,we introduce event-triggered inputs into the control strategy.It is proved by the Lyapunov stability analysis that all signals of the closed-loop system are bounded and the output of system eventually converge to a bounded region.The efficacy of the control approach is ultimately demonstrated via the simulation of an actual machine feeding system. 展开更多
关键词 Nonlinear interconnected large-scale systems Fully actuated system approach Actuator failures Neural networks
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Collaborative Approaches to Poverty Reduction:Experts and o"cials from China and abroad exchange views on cooperation and sustainable development at seminar
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作者 LU JIAJUN 《ChinAfrica》 2026年第2期34-35,共2页
The 17 Sustainable Development Goals(SDGs)for 2030,adopted by all United Nations member states in 2015,are facing a range of challenges.Factors such as climate change,regional conflicts and economic recession are havi... The 17 Sustainable Development Goals(SDGs)for 2030,adopted by all United Nations member states in 2015,are facing a range of challenges.Factors such as climate change,regional conflicts and economic recession are having a significant impact,particularly on global poverty governance.As a platform for dialogue,exchange and technical cooperation,the 2025 International Seminar on Global Poverty Reduction Partnerships was held in Beijing on 10 December 2025. 展开更多
关键词 climate changeregional conflicts collaborative approaches China global poverty reduction OFFICIALS sustainable development goals sdgs economic recession experts
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Fast identification of γ‑emitting radionuclides based on sequential Bayesian approach
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作者 Xuan Zhang Jian-Wei Huang +5 位作者 Lin-Jian Wan Jia-Cheng Liu Xiao-Le Zhang De-Hong Li Fei Tuo Zhi-Jun Yang 《Nuclear Science and Techniques》 2026年第2期1-15,共15页
The rapid identification of γ-emitting radionuclides with low activity levels in public areas is crucial for nuclear safety.However,classical methods rely on full-energy peaks in the integral spectrum,requiring suffi... The rapid identification of γ-emitting radionuclides with low activity levels in public areas is crucial for nuclear safety.However,classical methods rely on full-energy peaks in the integral spectrum,requiring sufficient count accumulation for evaluation,thereby limiting response time.The sequential Bayesian approach,which utilizes prior information and considers both photon energies and interarrival times,can significantly enhance the performance of radionuclides identification.This study proposes a theoretical optimization method for the traditional sequential Bayesian approach.Each photon is processed sequentially,and the corresponding posterior probability is updated in real time using a noninformative prior from the Bayesian theory.By comparing the posterior probabilities of the background and radionuclides based on the energy variance and time interval,the type of γ-rays can be identified(background characteristic γ-rays,Compton plateaus γ-rays,or radionuclide-specific characteristic γ-rays).By integrating the information from these multiple characteristic γ-rays,the presence and type of radionuclides were determined based on the final decision function and a set threshold.Based on theoretical research,verification experiments were conducted using a LaBr_(3)(Ce)detector in both low-and natural background radiation environments with typical radionuclides(^(137)Cs,^(60)Co,and ^(133)Ba).The results show that this approach can identify ^(137)Cs in 7.9 s and 8.5 s(source dose rate contribution:approximately 6.5×10^(−3)μGy/h),^(60)Co in 8.1 s and 9.8 s(approximately 4.8×10^(−2)μGy/h),and ^(133)Ba in 4.05 s and 5.99 s(approximately 3.4×10^(−2)μGy/h)under low and natural background radiation,respectively,with a miss rate below 0.01%.This demonstrates the effectiveness of the proposed approach for fast radionuclides identification,even at low activity levels and highlights its potential for enhancing public safety in diverse radiation environments. 展开更多
关键词 Sequential Bayesian approach Fast radionuclides identification LaBr_(3)(Ce)detector Low background radiation laboratory
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Trigeminal nerve stimulation as a neuromodulatory approach for disorders of consciousness
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作者 Bandy Chen 《Neural Regeneration Research》 2026年第8期3541-3542,共2页
Disorders of consciousness(DoC),including coma,vegetative state,and minimally conscious state,present a spectrum of conditions characterized by impaired awareness and responsiveness due to severe brain injury.Conventi... Disorders of consciousness(DoC),including coma,vegetative state,and minimally conscious state,present a spectrum of conditions characterized by impaired awareness and responsiveness due to severe brain injury.Conventional interventions for DoC primarily focus on promoting conditions conducive to spontaneous neurological recovery including pharmacological treatments such as dopaminergic agents(e.g.,amantadine)and rehabilitative strategies including sensory stimulation programs and physical therapy. 展开更多
关键词 neuromodulatory approach disorders consciousness doc including physical therapy pharmacological treatments sensory stimulation programs dopaminergic agents egamantadine promoting conditions rehabilitative strategies
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A Stochastic Optimal Control for a Class of LTI Systems With a State-Dependent Wiener Process:An Algebraic Approach
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作者 Kento Fujita Daisuke Tsubakino Shiuji Hara 《IEEE/CAA Journal of Automatica Sinica》 2026年第2期489-491,共3页
Dear Editor,In this letter,we focus on the algebraic relationship between the coefficient matrices and the solution of the stochastic algebraic Riccati equation.It is revealed that,if the coefficient matrices are in a... Dear Editor,In this letter,we focus on the algebraic relationship between the coefficient matrices and the solution of the stochastic algebraic Riccati equation.It is revealed that,if the coefficient matrices are in an algebra,then the solution(and also the control gain in many cases)is also in the same algebra.The main result is verified by a numerical simulation. 展开更多
关键词 stochastic optimal control algebraic relationship algebraic approach state dependent Wiener process coefficient matrices stochastic algebraic Riccati equation numerical simulation stochastic algebraic riccati equationit
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Strength prediction of multi-layered copper-based composites fabricated by accumulative roll bonding 被引量:10
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作者 P.SEIFOLLAHZADEH Morteza ALIZADEH M.R.ABBASI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第6期1729-1739,共11页
This work aims to evaluate the feasibility of the fabrication of nanostructured Cu/Al/Ag multi-layered composites by accumulative roll bonding(ARB),and to analyze the tensile properties and electrical conductivity of ... This work aims to evaluate the feasibility of the fabrication of nanostructured Cu/Al/Ag multi-layered composites by accumulative roll bonding(ARB),and to analyze the tensile properties and electrical conductivity of the produced composites.A theoretical model using strengthening mechanisms and some structural parameters extracted from X-ray diffraction is also developed to predict the tensile strength of the composites.It was found that by progression of ARB,the experimental and calculated tensile strengths are enhanced,reach a maximum of about 450 and 510 MPa at the fifth cycle of ARB,respectively and then are reduced.The electrical conductivity decreased slightly by increasing the number of ARB cycles at initial ARB cycles,but the decrease was intensified at the final ARB cycles.In conclusion,the merit of ARB to fabricate this type of multi-layered nanocomposites and the accuracy of the developed model to predict tensile strength were realized. 展开更多
关键词 multi-layered composites accumulative roll bonding strength prediction HARDNESS X-ray diffraction
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Seismogram Synthesis in Multi-layered Half-space Part Ⅰ. Theoretical Formulations 被引量:27
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作者 Chen XiaofeiDepartment of Geophysics, Peking University, Beijing 100871, China 《Earthquake Research in China》 1999年第2期53-78,共26页
In the past two decades numerous studies were made to develop and improve the theory and practical computation techniques of synthesizing theoretical seismograms for the model of multi-layered half-space. Today, synth... In the past two decades numerous studies were made to develop and improve the theory and practical computation techniques of synthesizing theoretical seismograms for the model of multi-layered half-space. Today, synthesizing theoretical seismograms in multi-layered half-space is an important tool for understanding the structure of the Earth’s interior as well as the seismic source process from well-recorded seismograms data. As part of a review of the state-of-the-art, in this article I shall present a systematic and self-contained theory of elastic waves in multi-layered half-space media based on the developments in the past two decades. 展开更多
关键词 SYNTHETIC seismogram multi-layered HALF-SPACE GENERALIZED reflectiontransmission COEFFICIENTS METHOD
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In-plane dynamic Green's functions for inclined and uniformly distributed loads in a multi-layered transversely isotropic half-space 被引量:4
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作者 Ba Zhenning Kang Zeqing Liang Jianwen 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2018年第2期293-309,共17页
The dynamic stiffness method combined with the Fourier transform is utilized to derive the in-plane Green’s functions for inclined and uniformly distributed loads in a multi-layered transversely isotropic(TI)half-s... The dynamic stiffness method combined with the Fourier transform is utilized to derive the in-plane Green’s functions for inclined and uniformly distributed loads in a multi-layered transversely isotropic(TI)half-space.The loaded layer is fixed to obtain solutions restricted in it and the corresponding reactions forces,which are then applied to the total system with the opposite sign.By adding solutions restricted in the loaded layer to solutions from the reaction forces,the global solutions in the wavenumber domain are obtained,and the dynamic Green’s functions in the space domain are recovered by the inverse Fourier transform.The presented formulations can be reduced to the isotropic case developed by Wolf(1985),and are further verified by comparisons with existing solutions in a uniform isotropic as well as a layered TI halfspace subjected to horizontally distributed loads which are special cases of the more general problem addressed.The deduced Green’s functions,in conjunction with boundary element methods,will lead to significant advances in the investigation of a variety of wave scattering,wave radiation and soil-structure interaction problems in a layered TI site.Selected numerical results are given to investigate the influence of material anisotropy,frequency of excitation,inclination angle and layered on the responses of displacement and stress,and some conclusions are drawn. 展开更多
关键词 Green's functions transversely isotropic medium multi-layered half-space stiffness method dynamic response
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