An estimated 130 million people worldwide are chronically infected with hepatitis C virus (HCV) making it a leading cause of liver disease worldwide. Because the currently available therapy of pegylated interferon-alp...An estimated 130 million people worldwide are chronically infected with hepatitis C virus (HCV) making it a leading cause of liver disease worldwide. Because the currently available therapy of pegylated interferon-alpha and ribavirin is only effective in a subset of patients, the development of new HCV antivirals is a healthcare imperative. This review discusses the experimental models available for HCV antiviral drug research, recent advances in HCV antiviral drug development, as well as active research being pursued to facilitate development of new HCV-specific therapeutics.展开更多
A system of systems(SoS)composes a set of independent constituent systems(CSs),where the degree of authority to control the independence of CSs varies,depending on different SoS types.Key researchers describe four SoS...A system of systems(SoS)composes a set of independent constituent systems(CSs),where the degree of authority to control the independence of CSs varies,depending on different SoS types.Key researchers describe four SoS types with descending levels of central authority:directed,acknowledged,collaborative and virtual.Although the definitions have been recognized in SoS engineering,what is challenging is the difficulty of translating these definitions into models and simulation environments.Thus,we provide a goal-based method including a mathematical baseline to translate these definitions into more effective agent-based modeling and simulations.First,we construct the theoretical models of CS and SoS.Based on the theoretical models,we analyze the degree of authority influenced by SoS characteristics.Next,we propose a definition of SoS types by quantitatively explaining the degree of authority.Finally,we recognize the differences between acknowledged SoS and collaborative SoS using a migrating waterfowl flock by an agentbased model(ABM)simulation.This paper contributes to the SoS body of knowledge by increasing our understanding of the degree of authority in an SoS,so we may identify suitable SoS types to achieve SoS goals by modeling and simulation.展开更多
To shed light on the subgrid-seale （SGS） modeling methodology of nonlinear systems such as the Navier-Stokes turbulence, we define the concepts of assumption and restriction in the modeling procedure, which are show...To shed light on the subgrid-seale （SGS） modeling methodology of nonlinear systems such as the Navier-Stokes turbulence, we define the concepts of assumption and restriction in the modeling procedure, which are shown by generalized derivation of three general mathematical constraints for different combinations of restrictions. These constraints are verified numerically in a one-dimensional nonlinear advection equation. This study is expected to inspire future research on the SGS modeling methodology of nonlinear systems.展开更多
Since the late 1950’s, the Malaysian human population has nearly quadrupled, increasing pressure on natural resource exploitation to meet domestic needs and to earn foreign exchange from exports. Global demand for Ma...Since the late 1950’s, the Malaysian human population has nearly quadrupled, increasing pressure on natural resource exploitation to meet domestic needs and to earn foreign exchange from exports. Global demand for Malaysian palm oil in particular had steeply increased since the mid-1970s and by 2013, the commodity was the leading foreign exchange earner. To fulfill and sustain this demand, the country’s economy has steadily shifted bias towards production and associated value addition of palm oil products for export. However, as a consequence, many of Malaysia’s natural tropical forests have been converted to palm oil farming resulting in loss of approximately 10,000 km2 of forest cover over the past twenty-five years, and biodiversity has been displaced or lost. To provide a deeper insight into the interplay amongst key interrelated environmental and socio-economic variables, and a forecast of possible future balance, we used a systems dynamism modeling tool, STELLAR (structural thinking, experiential learning laboratory with animation), to simulate and project how Malaysia could achieve a medium-term sustainable balance or optimization between palm oil production and forest conservation without compromising on human social welfare. The model consisted of four main modules (environmental, economic, social development and human welfare) each with component parameters, and interconnected by input and output loops. Model calibrations, testing and preruns involved existing official 30-year time-series datasets. Subsequently, four scenarios: Environmental conservation;Economic growth under increased global palm oil demand;Economy decline under decreased palm oil demand;and Control condition with little or no change, were selected for simulated projections of future possibilities. Simulation results showed that scenarios and variable interactions that reduce environmental damage would offer the best chance for optimizing the palm oil economy while also minimizing forest loss and promoting citizen social welfare.展开更多
Over the pastfive years,we have been making efforts to develop a practical and predic- tive tool to exploreforgiantore deposits in hydrothermal systems. Towards this goal,a sig- nificant progress has been made towards...Over the pastfive years,we have been making efforts to develop a practical and predic- tive tool to exploreforgiantore deposits in hydrothermal systems. Towards this goal,a sig- nificant progress has been made towards a better understanding of the basic physical and chemical processes behind ore body formation and mineralization in hydrothermal systems. On the scientific developmentside,we have developed analytical solutions to answerthe fol- lowing scientific questions:(1) Can thepore- fluid pressure gradientbemaintained atthe val- ue of the lithostaticpressure gradientin the uppercrustof the Earth?and(2 ) Can convective pore- fluid flow take place in the uppercrustof the Earth ifthere is a fluid/mass leakage from the mantle to the upper crustof the Earth?On the modelling developmentside,we have developed numerical methods to model the following problems:(1) convective pore- fluid flow in two- dimensional hydrothermal systems;(2 ) coupled reactive pore- fluid flow and multiple species transport in porous media;(3) precipitation and dissolution of minerals and rock al- teration in the upper crust of the Earth;(4 ) double diffusion driven reactive flow transport in deformable fluid- saturated porous media with particular consideration of temperature- de- pendentchemical reaction rates;(5 ) pore- fluid flow patterns neargeological lenses in hydro- dynamic and hydrothermal systems;(6 ) dissipative structures for nonequilibrium chemical reactions in fluid- saturated porousmedia;(7) convectivepore- fluid flow and the related min- eralization in three- dimensional hydrothermal systems;(8) fluid- rock interaction problems associated with the rock alteration and metamorphic process in fluid- saturated hydrothermal/ sedimentary basins;and (9) various aspects of the fully coupled problem involving material deformation,pore- fluid flow,heattransferand species transport/ chemical reactionsin pore- fluid saturated porous rock masses. The above- mentioned work has significantly enriched our knowledge about the physical and chemical processes related to ore body formation and mineralization in the upper crustof the展开更多
Objective: To explore nutritional support under the Neuman systems model in treating dysphagia in stroke patients. Methods: In this retrospective study, we enrolled 97 patients with dysphagia after stroke admitted to ...Objective: To explore nutritional support under the Neuman systems model in treating dysphagia in stroke patients. Methods: In this retrospective study, we enrolled 97 patients with dysphagia after stroke admitted to our hospital, and randomly divided them into the Neuman group (n = 51) given nursing intervention based on Neuman systems model and a control group (n = 46) given routine nursing intervention. Both groups received nutritional support for 3 months. Nutritional indexes (serum total protein, plasma albumin, serum albumin, hemoglobin and transferrin levels) and immune indexes (immunoglobulin (Ig) A, IgG, IgM and total lymphocyte count (TLC) in both groups were recorded and compared. Pulmonary function recovery, video fluoroscopic swallowing study score, water swallowing test score, complication rate, and health knowledge mastery level were also compared between the two groups. Results: After the intervention, the Neuman group showed less decrease in the nutritional and immune index scores (serum total protein, plasma albumin, hemoglobin, serum albumin;IgA, IgG, IgM, and TLC;all P Conclusion: For patients with stroke and dysphagia, comprehensive nursing intervention (e.g., nutritional support) under theNeuman systems model can promote the recovery of immune, swallowing, and pulmonary function, reduce complication incidence and facilitate comprehensive rehabilitation, ensuring adequate nutritional intake.展开更多
Ireproving the quality and experience perceived by the user is fundamental when de- veloping multimedia technologies, products, and services. Quality of experience （QoE） involves subjective perception, user behavior...Ireproving the quality and experience perceived by the user is fundamental when de- veloping multimedia technologies, products, and services. Quality of experience （QoE） involves subjective perception, user behavior and needs, appropriateness, con- text, and usability of delivered content. Modeling QoE is critical for enhancing QoE in various nmhimedia applications. In this special issue,展开更多
Background:This paper uses information visualization software to sort out the relevant research of Neuman systems model at home and abroad in the past 20 years,and discusses the research hotspots and development trend...Background:This paper uses information visualization software to sort out the relevant research of Neuman systems model at home and abroad in the past 20 years,and discusses the research hotspots and development trend in the field of Neuman systems model,so as to provide scientific and reliable reference for the future work and research.Methods:By using CiteSpace V software,this paper analyzes the literatures about the Neuman systems model collected in the core web of science database and CNKI database from 2001 to 2020,and analyzes the time distribution,research power distribution,research hotspots,research frontier and development trend of the Neuman systems model at home and abroad in the past 20 years.Results:The development trend of research in this field in foreign countries is relatively stable.The core strength of research is mainly in the United States,and the research hotspots are health,quality of life,caregivers,spirituality,etc;the research in this field in China is gradually on the rise,and there is no obvious research force,and the research hotspots are mainly quality of life,complications,anxiety,stressors,perioperative period,hypertension,etc.Conclusions:It has been proved that the model has a certain guiding effect on the development of nursing discipline in China.In China,there is still room for development in the research of this model.It is suggested that Chinese scholars can learn from foreign leading research forces to carry out in-depth research and expand its application scope.展开更多
The challenge of transitioning from temporary humanitarian settlements to more sustainable human settlements is due to a significant increase in the number of forcibly displaced people over recent decades, difficultie...The challenge of transitioning from temporary humanitarian settlements to more sustainable human settlements is due to a significant increase in the number of forcibly displaced people over recent decades, difficulties in providing social services that meet the required standards, and the prolongation of emergencies. Despite this challenging context, short-term considerations continue to guide their planning and management rather than more integrated, longer-term perspectives, thus preventing viable, sustainable development. Over the years, the design of humanitarian settlements has not been adapted to local contexts and perspectives, nor to the dynamics of urbanization and population growth and data. In addition, the current approach to temporary settlement harms the environment and can strain limited resources. Inefficient land use and ad hoc development models have compounded difficulties and generated new challenges. As a result, living conditions in settlements have deteriorated over the last few decades and continue to pose new challenges. The stakes are such that major shortcomings have emerged along the way, leading to disruption, budget overruns in a context marked by a steady decline in funding. However, some attempts have been made to shift towards more sustainable approaches, but these have mainly focused on vague, sector-oriented themes, failing to consider systematic and integration views. This study is a contribution in addressing these shortcomings by designing a model-driving solution, emphasizing an integrated system conceptualized as a system of systems. This paper proposes a new methodology for designing an integrated and sustainable human settlement model, based on Model-Based Systems Engineering and a Systems Modeling Language to provide valuable insights toward sustainable solutions for displaced populations aligning with the United Nations 2030 agenda for sustainable development.展开更多
A new symmetric model for predicting ternary thermodynamic properties from its three binary systems has been presented. The application of this new model to the prediction of the ternary mixing enthalpy of Ga-Bi-Sn sy...A new symmetric model for predicting ternary thermodynamic properties from its three binary systems has been presented. The application of this new model to the prediction of the ternary mixing enthalpy of Ga-Bi-Sn system and the ternary excess Gibbs energy of AgCl-LiCl-KCl system shows that the calculated results are close to the experimental data.展开更多
The enhanced definition of Mechatronics involves the four underlying characteristics of integrated,unified,unique,and systematic approaches.In this realm,Mechatronics is not limited to electro-mechanical systems,in th...The enhanced definition of Mechatronics involves the four underlying characteristics of integrated,unified,unique,and systematic approaches.In this realm,Mechatronics is not limited to electro-mechanical systems,in the multi-physics sense,but involves other physical domains such as fluid and thermal.This paper summarizes the mechatronic approach to modeling.Linear graphs facilitate the development of state-space models of mechatronic systems,through this approach.The use of linear graphs in mechatronic modeling is outlined and an illustrative example of sound system modeling is given.Both time-domain and frequency-domain approaches are presented for the use of linear graphs.A mechatronic model of a multi-physics system may be simplified by converting all the physical domains into an equivalent single-domain system that is entirely in the output domain of the system.This approach of converting(transforming)physical domains is presented.An illustrative example of a pressure-controlled hydraulic actuator system that operates a mechanical load is given.展开更多
BACKGROUND Owing to age-related physiological declines,elderly patients undergoing radical gastrectomy(RG)often experience physical and psychological challenges.Hence,appropriate nursing strategies need to be identifi...BACKGROUND Owing to age-related physiological declines,elderly patients undergoing radical gastrectomy(RG)often experience physical and psychological challenges.Hence,appropriate nursing strategies need to be identified for optimizing patient outcomes.AIM To evaluate the effects of the Neuman Systems Model-guided stepped care intervention(NGSC)model on postoperative physical and psychological recovery in elderly patients with gastric cancer who underwent RG.METHODS In total,80 elderly patients(≥65 years old)who underwent RG at the Shanxi Fenyang Hospital between January 2023 and June 2024 were included and randomly divided as follows:Control group(n=40,those receiving conventional stepped care intervention);observation group(n=40,those receiving NGSC).Postoperative recovery indices,anxiety/depression scores(Self-Rating Anxiety Scale/Self-Rating Depression Scale),quality of life(36-item short form health survey),and adverse event rates were compared between the groups.RESULTS Compared with the control group,the observation group presented significantly shorter recovery times for first bowel sounds,ambulation,flatus,oral intake,catheter removal,and hospitalization(all P<0.05).Notably,in the observation group,Self-Rating Anxiety Scale/Self-Rating Depression Scale scores and the adverse event rate were significantly lower(all P<0.05),whereas 36-item short form health survey scores were higher(P<0.05),compared with those in the control group.CONCLUSION Overall,the findings of this study show that the proposed NGSC model accelerates postoperative recovery,alleviates psychological distress,improves quality of life,and reduces complications in elderly patients with gastric cancer who underwent RG,presenting potential for clinical application.展开更多
Architecture framework has become an effective method recently to describe the system of systems(SoS)architecture,such as the United States(US)Department of Defense Architecture Framework Version 2.0(DoDAF2.0).As a vi...Architecture framework has become an effective method recently to describe the system of systems(SoS)architecture,such as the United States(US)Department of Defense Architecture Framework Version 2.0(DoDAF2.0).As a viewpoint in DoDAF2.0,the operational viewpoint(OV)describes operational activities,nodes,and resource flows.The OV models are important for SoS architecture development.However,as the SoS complexity increases,constructing OV models with traditional methods exposes shortcomings,such as inefficient data collection and low modeling standards.Therefore,we propose an intelligent modeling method for five OV models,including operational resource flow OV-2,organizational relationships OV-4,operational activity hierarchy OV-5a,operational activities model OV-5b,and operational activity sequences OV-6c.The main idea of the method is to extract OV architecture data from text and generate interoperable OV models.First,we construct the OV meta model based on the DoDAF2.0 meta model(DM2).Second,OV architecture named entities is recognized from text based on the bidirectional long short-term memory and conditional random field(BiLSTM-CRF)model.And OV architecture relationships are collected with relationship extraction rules.Finally,we define the generation rules for OV models and develop an OV modeling tool.We use unmanned surface vehicles(USV)swarm target defense SoS architecture as a case to verify the feasibility and effectiveness of the intelligent modeling method.展开更多
By analyzing the observed phenomena and the data collected in the study, a multi-compartment linear circulation model for targeting drug delivery system was developed and the function formulas of the drug concentratio...By analyzing the observed phenomena and the data collected in the study, a multi-compartment linear circulation model for targeting drug delivery system was developed and the function formulas of the drug concentration-time in blood and target organ by computing were figured out. The drug concentration-time curve for target organ can be plotted with reference to the data of drug concentration in blood according to the model. The pharmacokinetic parameters of the drug in target organ could also be obtained. The practicability of the model was further checked by the curves of drug concentration-time in blood and target organ(liver) of liver-targeting nanoparticles in animal tests. Based on the liver drug concentration-time curves calculated by the function formula of the drug in target organ, the pharmacokinetic behavior of the drug in target organ(liver) was analyzed by statistical moment, and its pharmacokinetic parameters in liver were obtained. It is suggested that the (relative targeting index( can be used for quantitative evaluation of the targeting drug delivery systems.展开更多
Parkinson's disease,the most common movement disorder,has a strong neuroinflammatory aspect.This is evident by increased pro-inflammatory cytokines in the serum,and the presence of activated microglial cells,and i...Parkinson's disease,the most common movement disorder,has a strong neuroinflammatory aspect.This is evident by increased pro-inflammatory cytokines in the serum,and the presence of activated microglial cells,and inflammatory cytokines in the substantia nigra of post-mortem brains as well as cerebrospinal fluid of Parkinson's disease patients.The central and peripheral neuroinflammatory aspects of Parkinson's disease can be investigated in vivo via administration of the inflammagen lipopolysaccharide,a component of the cell wall of gram-negative bacteria.In this mini-review,we will critically evaluate different routes of lipopolysaccharide administration(including intranasal systemic and ste reotasic),their relevance to clinical Parkinson's disease as well as the recent findings in lipopolysaccharide mouse models.We will also share our own expe riences with systemic and intrastriatal lipopolysaccharide models in C57BL/6 mice and will discuss the usefulness of lipopolysaccharide mouse models for future research in the field.展开更多
The output feedback model predictive control(MPC),for a linear parameter varying(LPV) process system including unmeasurable model parameters and disturbance(all lying in known polytopes),is considered.Some previously ...The output feedback model predictive control(MPC),for a linear parameter varying(LPV) process system including unmeasurable model parameters and disturbance(all lying in known polytopes),is considered.Some previously developed tools,including the norm-bounding technique for relaxing the disturbance-related constraint handling,the dynamic output feedback law,the notion of quadratic boundedness for specifying the closed-loop stability,and the ellipsoidal state estimation error bound for guaranteeing the recursive feasibility,are merged in the control design.Some previous approaches are shown to be the special cases.An example of continuous stirred tank reactor(CSTR) is given to show the effectiveness of the proposed approaches.展开更多
Traffic modeling is a key step in several intelligent transportation systems（ITS） applications. This paper regards the traffic modeling through the enhancement of the cell transmission model. It considers the traffi...Traffic modeling is a key step in several intelligent transportation systems（ITS） applications. This paper regards the traffic modeling through the enhancement of the cell transmission model. It considers the traffic flow as a hybrid dynamic system and proposes a piecewise switched linear traffic model. The latter allows an accurate modeling of the traffic flow in a given section by considering its geometry. On the other hand, the piecewise switched linear traffic model handles more than one congestion wave and has the advantage to be modular. The measurements at upstream and downstream boundaries are also used in this model in order to decouple the traffic flow dynamics of successive road portions. Finally, real magnetic sensor data, provided by the performance measurement system on a portion of the Californian SR60-E highway are used to validate the proposed model.展开更多
An improved nonlinear adaptive switching control method is presented to relax the assumption on the higher order nonlinear terms of a class of discrete-time non-affine nonlinear systems. The proposed control strategy ...An improved nonlinear adaptive switching control method is presented to relax the assumption on the higher order nonlinear terms of a class of discrete-time non-affine nonlinear systems. The proposed control strategy is composed of a linear adaptive controller, a neural network(NN) based nonlinear adaptive controller and a switching mechanism. An incremental model is derived to represent the considered system and an improved robust adaptive law is chosen to update the parameters of the linear adaptive controller. A new performance criterion of the switching mechanism is designed to select the proper controller. Using this control scheme, all the signals in the system are proved to be bounded. Numerical examples verify the effectiveness of the proposed algorithm.展开更多
The Hani Rice Terraces System, based on gravity-flow irrigation, is one of the Globally Important Agricultural Heritage Systems(GIAHS) pilot sites selected by FAO in 2010. The water resource plays an important role in...The Hani Rice Terraces System, based on gravity-flow irrigation, is one of the Globally Important Agricultural Heritage Systems(GIAHS) pilot sites selected by FAO in 2010. The water resource plays an important role in the sustainable development of this system. The value of water conserved by the forest is influenced by natural, economic and social factors. In this paper, the water quality, per capita water resources, per capita GDP and population density are chosen as indices to construct an index system for a comprehensive evaluation of water resources value. The weights of these indices are 0.443, 0.31, 0.141 and 0.106 respectively, which are determined by the analytic hierarchy process(AHP) method. The water resources value has been assessed by the fuzzy comprehensive evaluation model. The results show that the water resources value in the Hani Rice Terraces System is 4.25 RMB/m^3. Evaluating the value of water resources in the Hani Rice Terraces System can provide a reference for ecological compensation, for raising public awareness of the importance of protecting the system, and ultimately achieving its sustainable development.展开更多
基金The financial support for this study by National Natural Science Foundation of China(No.30960242)National Basic Research Program of China(973 program)(No.2012CB720805)Training Project of Young Scientists of Jiangxi Province(Stars of Jing gang)is gratefully acknowledged.
基金supported by National Institutes of Health grants AI070827 and CA33266American Cancer Society grant RSG-09-076-01 and the UIC Walter Payton Center GUILD
文摘An estimated 130 million people worldwide are chronically infected with hepatitis C virus (HCV) making it a leading cause of liver disease worldwide. Because the currently available therapy of pegylated interferon-alpha and ribavirin is only effective in a subset of patients, the development of new HCV antivirals is a healthcare imperative. This review discusses the experimental models available for HCV antiviral drug research, recent advances in HCV antiviral drug development, as well as active research being pursued to facilitate development of new HCV-specific therapeutics.
基金supported by the National Key Research and Development Program of China(61873236)the Natural Science Foundation of Zhejiang Province(LZ21F020003,LY18F030001)the Civil Aerospace Pre-research Project(D020101).
文摘A system of systems(SoS)composes a set of independent constituent systems(CSs),where the degree of authority to control the independence of CSs varies,depending on different SoS types.Key researchers describe four SoS types with descending levels of central authority:directed,acknowledged,collaborative and virtual.Although the definitions have been recognized in SoS engineering,what is challenging is the difficulty of translating these definitions into models and simulation environments.Thus,we provide a goal-based method including a mathematical baseline to translate these definitions into more effective agent-based modeling and simulations.First,we construct the theoretical models of CS and SoS.Based on the theoretical models,we analyze the degree of authority influenced by SoS characteristics.Next,we propose a definition of SoS types by quantitatively explaining the degree of authority.Finally,we recognize the differences between acknowledged SoS and collaborative SoS using a migrating waterfowl flock by an agentbased model(ABM)simulation.This paper contributes to the SoS body of knowledge by increasing our understanding of the degree of authority in an SoS,so we may identify suitable SoS types to achieve SoS goals by modeling and simulation.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11572025,11202013 and 51420105008
文摘To shed light on the subgrid-seale （SGS） modeling methodology of nonlinear systems such as the Navier-Stokes turbulence, we define the concepts of assumption and restriction in the modeling procedure, which are shown by generalized derivation of three general mathematical constraints for different combinations of restrictions. These constraints are verified numerically in a one-dimensional nonlinear advection equation. This study is expected to inspire future research on the SGS modeling methodology of nonlinear systems.
文摘Since the late 1950’s, the Malaysian human population has nearly quadrupled, increasing pressure on natural resource exploitation to meet domestic needs and to earn foreign exchange from exports. Global demand for Malaysian palm oil in particular had steeply increased since the mid-1970s and by 2013, the commodity was the leading foreign exchange earner. To fulfill and sustain this demand, the country’s economy has steadily shifted bias towards production and associated value addition of palm oil products for export. However, as a consequence, many of Malaysia’s natural tropical forests have been converted to palm oil farming resulting in loss of approximately 10,000 km2 of forest cover over the past twenty-five years, and biodiversity has been displaced or lost. To provide a deeper insight into the interplay amongst key interrelated environmental and socio-economic variables, and a forecast of possible future balance, we used a systems dynamism modeling tool, STELLAR (structural thinking, experiential learning laboratory with animation), to simulate and project how Malaysia could achieve a medium-term sustainable balance or optimization between palm oil production and forest conservation without compromising on human social welfare. The model consisted of four main modules (environmental, economic, social development and human welfare) each with component parameters, and interconnected by input and output loops. Model calibrations, testing and preruns involved existing official 30-year time-series datasets. Subsequently, four scenarios: Environmental conservation;Economic growth under increased global palm oil demand;Economy decline under decreased palm oil demand;and Control condition with little or no change, were selected for simulated projections of future possibilities. Simulation results showed that scenarios and variable interactions that reduce environmental damage would offer the best chance for optimizing the palm oil economy while also minimizing forest loss and promoting citizen social welfare.
文摘Over the pastfive years,we have been making efforts to develop a practical and predic- tive tool to exploreforgiantore deposits in hydrothermal systems. Towards this goal,a sig- nificant progress has been made towards a better understanding of the basic physical and chemical processes behind ore body formation and mineralization in hydrothermal systems. On the scientific developmentside,we have developed analytical solutions to answerthe fol- lowing scientific questions:(1) Can thepore- fluid pressure gradientbemaintained atthe val- ue of the lithostaticpressure gradientin the uppercrustof the Earth?and(2 ) Can convective pore- fluid flow take place in the uppercrustof the Earth ifthere is a fluid/mass leakage from the mantle to the upper crustof the Earth?On the modelling developmentside,we have developed numerical methods to model the following problems:(1) convective pore- fluid flow in two- dimensional hydrothermal systems;(2 ) coupled reactive pore- fluid flow and multiple species transport in porous media;(3) precipitation and dissolution of minerals and rock al- teration in the upper crust of the Earth;(4 ) double diffusion driven reactive flow transport in deformable fluid- saturated porous media with particular consideration of temperature- de- pendentchemical reaction rates;(5 ) pore- fluid flow patterns neargeological lenses in hydro- dynamic and hydrothermal systems;(6 ) dissipative structures for nonequilibrium chemical reactions in fluid- saturated porousmedia;(7) convectivepore- fluid flow and the related min- eralization in three- dimensional hydrothermal systems;(8) fluid- rock interaction problems associated with the rock alteration and metamorphic process in fluid- saturated hydrothermal/ sedimentary basins;and (9) various aspects of the fully coupled problem involving material deformation,pore- fluid flow,heattransferand species transport/ chemical reactionsin pore- fluid saturated porous rock masses. The above- mentioned work has significantly enriched our knowledge about the physical and chemical processes related to ore body formation and mineralization in the upper crustof the
文摘Objective: To explore nutritional support under the Neuman systems model in treating dysphagia in stroke patients. Methods: In this retrospective study, we enrolled 97 patients with dysphagia after stroke admitted to our hospital, and randomly divided them into the Neuman group (n = 51) given nursing intervention based on Neuman systems model and a control group (n = 46) given routine nursing intervention. Both groups received nutritional support for 3 months. Nutritional indexes (serum total protein, plasma albumin, serum albumin, hemoglobin and transferrin levels) and immune indexes (immunoglobulin (Ig) A, IgG, IgM and total lymphocyte count (TLC) in both groups were recorded and compared. Pulmonary function recovery, video fluoroscopic swallowing study score, water swallowing test score, complication rate, and health knowledge mastery level were also compared between the two groups. Results: After the intervention, the Neuman group showed less decrease in the nutritional and immune index scores (serum total protein, plasma albumin, hemoglobin, serum albumin;IgA, IgG, IgM, and TLC;all P Conclusion: For patients with stroke and dysphagia, comprehensive nursing intervention (e.g., nutritional support) under theNeuman systems model can promote the recovery of immune, swallowing, and pulmonary function, reduce complication incidence and facilitate comprehensive rehabilitation, ensuring adequate nutritional intake.
文摘Ireproving the quality and experience perceived by the user is fundamental when de- veloping multimedia technologies, products, and services. Quality of experience （QoE） involves subjective perception, user behavior and needs, appropriateness, con- text, and usability of delivered content. Modeling QoE is critical for enhancing QoE in various nmhimedia applications. In this special issue,
基金This study was supported by Reform Research of Education and Teaching in Tianjin University of Traditional Chinese Medicine(No.2016JYF09).
文摘Background:This paper uses information visualization software to sort out the relevant research of Neuman systems model at home and abroad in the past 20 years,and discusses the research hotspots and development trend in the field of Neuman systems model,so as to provide scientific and reliable reference for the future work and research.Methods:By using CiteSpace V software,this paper analyzes the literatures about the Neuman systems model collected in the core web of science database and CNKI database from 2001 to 2020,and analyzes the time distribution,research power distribution,research hotspots,research frontier and development trend of the Neuman systems model at home and abroad in the past 20 years.Results:The development trend of research in this field in foreign countries is relatively stable.The core strength of research is mainly in the United States,and the research hotspots are health,quality of life,caregivers,spirituality,etc;the research in this field in China is gradually on the rise,and there is no obvious research force,and the research hotspots are mainly quality of life,complications,anxiety,stressors,perioperative period,hypertension,etc.Conclusions:It has been proved that the model has a certain guiding effect on the development of nursing discipline in China.In China,there is still room for development in the research of this model.It is suggested that Chinese scholars can learn from foreign leading research forces to carry out in-depth research and expand its application scope.
文摘The challenge of transitioning from temporary humanitarian settlements to more sustainable human settlements is due to a significant increase in the number of forcibly displaced people over recent decades, difficulties in providing social services that meet the required standards, and the prolongation of emergencies. Despite this challenging context, short-term considerations continue to guide their planning and management rather than more integrated, longer-term perspectives, thus preventing viable, sustainable development. Over the years, the design of humanitarian settlements has not been adapted to local contexts and perspectives, nor to the dynamics of urbanization and population growth and data. In addition, the current approach to temporary settlement harms the environment and can strain limited resources. Inefficient land use and ad hoc development models have compounded difficulties and generated new challenges. As a result, living conditions in settlements have deteriorated over the last few decades and continue to pose new challenges. The stakes are such that major shortcomings have emerged along the way, leading to disruption, budget overruns in a context marked by a steady decline in funding. However, some attempts have been made to shift towards more sustainable approaches, but these have mainly focused on vague, sector-oriented themes, failing to consider systematic and integration views. This study is a contribution in addressing these shortcomings by designing a model-driving solution, emphasizing an integrated system conceptualized as a system of systems. This paper proposes a new methodology for designing an integrated and sustainable human settlement model, based on Model-Based Systems Engineering and a Systems Modeling Language to provide valuable insights toward sustainable solutions for displaced populations aligning with the United Nations 2030 agenda for sustainable development.
文摘A new symmetric model for predicting ternary thermodynamic properties from its three binary systems has been presented. The application of this new model to the prediction of the ternary mixing enthalpy of Ga-Bi-Sn system and the ternary excess Gibbs energy of AgCl-LiCl-KCl system shows that the calculated results are close to the experimental data.
基金supported by research grants from the Natural Sciences and Engineering Research Council(NSERC)of Canada
文摘The enhanced definition of Mechatronics involves the four underlying characteristics of integrated,unified,unique,and systematic approaches.In this realm,Mechatronics is not limited to electro-mechanical systems,in the multi-physics sense,but involves other physical domains such as fluid and thermal.This paper summarizes the mechatronic approach to modeling.Linear graphs facilitate the development of state-space models of mechatronic systems,through this approach.The use of linear graphs in mechatronic modeling is outlined and an illustrative example of sound system modeling is given.Both time-domain and frequency-domain approaches are presented for the use of linear graphs.A mechatronic model of a multi-physics system may be simplified by converting all the physical domains into an equivalent single-domain system that is entirely in the output domain of the system.This approach of converting(transforming)physical domains is presented.An illustrative example of a pressure-controlled hydraulic actuator system that operates a mechanical load is given.
文摘BACKGROUND Owing to age-related physiological declines,elderly patients undergoing radical gastrectomy(RG)often experience physical and psychological challenges.Hence,appropriate nursing strategies need to be identified for optimizing patient outcomes.AIM To evaluate the effects of the Neuman Systems Model-guided stepped care intervention(NGSC)model on postoperative physical and psychological recovery in elderly patients with gastric cancer who underwent RG.METHODS In total,80 elderly patients(≥65 years old)who underwent RG at the Shanxi Fenyang Hospital between January 2023 and June 2024 were included and randomly divided as follows:Control group(n=40,those receiving conventional stepped care intervention);observation group(n=40,those receiving NGSC).Postoperative recovery indices,anxiety/depression scores(Self-Rating Anxiety Scale/Self-Rating Depression Scale),quality of life(36-item short form health survey),and adverse event rates were compared between the groups.RESULTS Compared with the control group,the observation group presented significantly shorter recovery times for first bowel sounds,ambulation,flatus,oral intake,catheter removal,and hospitalization(all P<0.05).Notably,in the observation group,Self-Rating Anxiety Scale/Self-Rating Depression Scale scores and the adverse event rate were significantly lower(all P<0.05),whereas 36-item short form health survey scores were higher(P<0.05),compared with those in the control group.CONCLUSION Overall,the findings of this study show that the proposed NGSC model accelerates postoperative recovery,alleviates psychological distress,improves quality of life,and reduces complications in elderly patients with gastric cancer who underwent RG,presenting potential for clinical application.
基金National Natural Science Foundation of China(71690233,71971213,71901214)。
文摘Architecture framework has become an effective method recently to describe the system of systems(SoS)architecture,such as the United States(US)Department of Defense Architecture Framework Version 2.0(DoDAF2.0).As a viewpoint in DoDAF2.0,the operational viewpoint(OV)describes operational activities,nodes,and resource flows.The OV models are important for SoS architecture development.However,as the SoS complexity increases,constructing OV models with traditional methods exposes shortcomings,such as inefficient data collection and low modeling standards.Therefore,we propose an intelligent modeling method for five OV models,including operational resource flow OV-2,organizational relationships OV-4,operational activity hierarchy OV-5a,operational activities model OV-5b,and operational activity sequences OV-6c.The main idea of the method is to extract OV architecture data from text and generate interoperable OV models.First,we construct the OV meta model based on the DoDAF2.0 meta model(DM2).Second,OV architecture named entities is recognized from text based on the bidirectional long short-term memory and conditional random field(BiLSTM-CRF)model.And OV architecture relationships are collected with relationship extraction rules.Finally,we define the generation rules for OV models and develop an OV modeling tool.We use unmanned surface vehicles(USV)swarm target defense SoS architecture as a case to verify the feasibility and effectiveness of the intelligent modeling method.
文摘By analyzing the observed phenomena and the data collected in the study, a multi-compartment linear circulation model for targeting drug delivery system was developed and the function formulas of the drug concentration-time in blood and target organ by computing were figured out. The drug concentration-time curve for target organ can be plotted with reference to the data of drug concentration in blood according to the model. The pharmacokinetic parameters of the drug in target organ could also be obtained. The practicability of the model was further checked by the curves of drug concentration-time in blood and target organ(liver) of liver-targeting nanoparticles in animal tests. Based on the liver drug concentration-time curves calculated by the function formula of the drug in target organ, the pharmacokinetic behavior of the drug in target organ(liver) was analyzed by statistical moment, and its pharmacokinetic parameters in liver were obtained. It is suggested that the (relative targeting index( can be used for quantitative evaluation of the targeting drug delivery systems.
文摘Parkinson's disease,the most common movement disorder,has a strong neuroinflammatory aspect.This is evident by increased pro-inflammatory cytokines in the serum,and the presence of activated microglial cells,and inflammatory cytokines in the substantia nigra of post-mortem brains as well as cerebrospinal fluid of Parkinson's disease patients.The central and peripheral neuroinflammatory aspects of Parkinson's disease can be investigated in vivo via administration of the inflammagen lipopolysaccharide,a component of the cell wall of gram-negative bacteria.In this mini-review,we will critically evaluate different routes of lipopolysaccharide administration(including intranasal systemic and ste reotasic),their relevance to clinical Parkinson's disease as well as the recent findings in lipopolysaccharide mouse models.We will also share our own expe riences with systemic and intrastriatal lipopolysaccharide models in C57BL/6 mice and will discuss the usefulness of lipopolysaccharide mouse models for future research in the field.
基金Supported by the National High Technology Research and Development Program of China(2014AA041802)the National Natural Science Foundation of China(61573269)
文摘The output feedback model predictive control(MPC),for a linear parameter varying(LPV) process system including unmeasurable model parameters and disturbance(all lying in known polytopes),is considered.Some previously developed tools,including the norm-bounding technique for relaxing the disturbance-related constraint handling,the dynamic output feedback law,the notion of quadratic boundedness for specifying the closed-loop stability,and the ellipsoidal state estimation error bound for guaranteeing the recursive feasibility,are merged in the control design.Some previous approaches are shown to be the special cases.An example of continuous stirred tank reactor(CSTR) is given to show the effectiveness of the proposed approaches.
文摘Traffic modeling is a key step in several intelligent transportation systems（ITS） applications. This paper regards the traffic modeling through the enhancement of the cell transmission model. It considers the traffic flow as a hybrid dynamic system and proposes a piecewise switched linear traffic model. The latter allows an accurate modeling of the traffic flow in a given section by considering its geometry. On the other hand, the piecewise switched linear traffic model handles more than one congestion wave and has the advantage to be modular. The measurements at upstream and downstream boundaries are also used in this model in order to decouple the traffic flow dynamics of successive road portions. Finally, real magnetic sensor data, provided by the performance measurement system on a portion of the Californian SR60-E highway are used to validate the proposed model.
基金Supported by the National Natural Science Foundation of China(61333010,21376077,61203157)the Natural Science Foundation of Shanghai(14ZR1421800)State Key Laboratory of Synthetical Automation for Process Industries(PAL-N201404)
文摘An improved nonlinear adaptive switching control method is presented to relax the assumption on the higher order nonlinear terms of a class of discrete-time non-affine nonlinear systems. The proposed control strategy is composed of a linear adaptive controller, a neural network(NN) based nonlinear adaptive controller and a switching mechanism. An incremental model is derived to represent the considered system and an improved robust adaptive law is chosen to update the parameters of the linear adaptive controller. A new performance criterion of the switching mechanism is designed to select the proper controller. Using this control scheme, all the signals in the system are proved to be bounded. Numerical examples verify the effectiveness of the proposed algorithm.
基金financially supported by the National Natural Science Fund, China (Grant Nos. 31200376, 41201586)the CAS Visiting Professor-Ship for Senior International Scientists (Grant No. 2013T2Z0011)
文摘The Hani Rice Terraces System, based on gravity-flow irrigation, is one of the Globally Important Agricultural Heritage Systems(GIAHS) pilot sites selected by FAO in 2010. The water resource plays an important role in the sustainable development of this system. The value of water conserved by the forest is influenced by natural, economic and social factors. In this paper, the water quality, per capita water resources, per capita GDP and population density are chosen as indices to construct an index system for a comprehensive evaluation of water resources value. The weights of these indices are 0.443, 0.31, 0.141 and 0.106 respectively, which are determined by the analytic hierarchy process(AHP) method. The water resources value has been assessed by the fuzzy comprehensive evaluation model. The results show that the water resources value in the Hani Rice Terraces System is 4.25 RMB/m^3. Evaluating the value of water resources in the Hani Rice Terraces System can provide a reference for ecological compensation, for raising public awareness of the importance of protecting the system, and ultimately achieving its sustainable development.
