BACKGROUND In brain death donors(BDDs),donor management is the key in the complex donation process.Donor management goals,which are standards of care or clinical parameters,have been considered an acceptable barometer...BACKGROUND In brain death donors(BDDs),donor management is the key in the complex donation process.Donor management goals,which are standards of care or clinical parameters,have been considered an acceptable barometer of successful donor management.AIM To test the hypothesis that aetiology of brain death could influence haemodynamic management in BDDs.METHODS Haemodynamic data(blood pressure,heart rate,central venous pressure,lactate,urine output,and vasoactive drugs)of BDDs were recorded on intensive care unit(ICU)admission and during the 6-h observation period(Time 1 at the beginning;Time 2 at the end).RESULTS The study population was divided into three groups according to the aetiology of brain death:Stroke(n=71),traumatic brain injury(n=48),and postanoxic encephalopathy(n=19).On ICU admission,BDDs with postanoxic encephalopathy showed the lowest values of systolic and diastolic blood pressure associated with higher values of heart rate and lactate and a higher need of norepinephrine and other vasoactive drugs.At the beginning of the 6-h period(Time 1),BDDs with postanoxic encephalopathy showed higher values of heart rate,lactate,and central venous pressure together with a higher need of other vasoactive drugs.CONCLUSION According to our data,haemodynamic management of BDDs is affected by the aetiology of brain death.BDDs with postanoxic encephalopathy have higher requirements for norepinephrine and other vasoactive drugs.展开更多
The virtual enterprise will play a more and more im po rtant role in economy development. The virtual enterprise leader raises market a daptability and group cooperation ability through its dynamic management. Thus t ...The virtual enterprise will play a more and more im po rtant role in economy development. The virtual enterprise leader raises market a daptability and group cooperation ability through its dynamic management. Thus t he validity and efficiency of leader’s dynamic management determines the efficie ncy of the virtual enterprise operation, and the validity of the information flo w is one of the main factors. In this paper, the validity of the information flo w in the course of the leader’s dynamic management in the virtual enterprise is analyzed by using the economic searching theory and the information theory, and the possible ways to improve the validity and efficiency of leader’s dynamic man agement are indicated. Firstly, the basic concepts such as leader’s dynamic management, virtual enterpr ise, and its leader are defined. The dynamic management procedure for the virtua l enterprise leader is analyzed with the dynamic theory raised by Mowshowitz. Secondly, the model for the dynamic management of the virtual enterprise leader is constructed using multi-goal selection. The information flow validity for th e leader during the stages of the identification and the establishment is analyz ed with the economic searching theory and the information theory. Meanwhile, the value of the dynamic management policy is discussed with the information va lue theory. Finally, two ways to improve the validity of the information flow are obtained. The first way is to process the various kinds of information of the existing mem bers in the virtual enterprise for the future cooperative usage and to extend th e selective objects for the leader, and to make the detailed and clear mechanism of the object evaluation and selection (the market chance and the cooperative partner). The other way is to build the system of the effective transfer and process of the feedback information flow during the operation of the virtual ent erprise based on the information technology.展开更多
The rapid economic development has promoted the construction of infrastructure,such as highways and water conservancy projects.The establishment of highways has facilitated people's lives and made the distance bet...The rapid economic development has promoted the construction of infrastructure,such as highways and water conservancy projects.The establishment of highways has facilitated people's lives and made the distance between regions shorter and shorter.However,the construction of highway engineering is a big project,which not only has a long cycle,but also has a high economic cost.During the construction process,a large number of construction materials and personnel will be applied.If the project cost management is not implemented for the highway construction,it will easily affect the final quality and profit of the entire project.This article expounds the significance of dynamic management and control of highway engineering cost,and analyzes the strategy of dynamic management and control of highway engineering cost.展开更多
With the continuous improvement of urbanization level,the construction of municipal roads has received more attention.The rational application of dynamic management mode to the survey and design management of municipa...With the continuous improvement of urbanization level,the construction of municipal roads has received more attention.The rational application of dynamic management mode to the survey and design management of municipal roads is conducive to improve the survey and design management level of municipal roads and further realizing the optimization of the construction effect of municipal roads.In this paper,the various factors which are affecting the management of municipal road survey and design as well the principles of municipal road design were discussed.Further,the recommendation of the application strategy of dynamic management mode in municipal road survey and design management was proposed in this paper.展开更多
BACKGROUND Acute lung injury(ALI)after liver transplantation(LT)may lead to acute respiratory distress syndrome,which is associated with adverse postoperative outcomes,such as prolonged hospital stay,high morbidity,an...BACKGROUND Acute lung injury(ALI)after liver transplantation(LT)may lead to acute respiratory distress syndrome,which is associated with adverse postoperative outcomes,such as prolonged hospital stay,high morbidity,and mortality.Therefore,it is vital to maintain hemodynamic stability and optimize fluid management.However,few studies have reported cardiac output-guided(CO-G)management in pediatric LT.AIM To investigate the effect of CO-G hemodynamic management on early postoperative ALI and hemodynamic stability during pediatric living donor LT.METHODS A total of 130 pediatric patients scheduled for elective living donor LT were enrolled as study participants and were assigned to the control group(65 cases)and CO-G group(65 cases).In the CO-G group,CO was considered the target for hemodynamic management.In the control group,hemodynamic management was based on usual perioperative care guided by central venous pressure,continuous invasive arterial pressure,urinary volume,etc.The primary outcome was early postoperative ALI.Secondary outcomes included other early postoperative pulmonary complications,readmission to the intense care unit(ICU)for pulmonary complications,ICU stay,hospital stay,and in-hospital mortality.RESULTS The incidence of early postoperative ALI was 27.7%in the CO-G group,which was significantly lower than that in the control group(44.6%)(P<0.05).During the surgery,the incidence of postreperfusion syndrome was lower in the CO-G group(P<0.05).The level of intraoperative positive fluid transfusions was lower and the rate of dobutamine use before portal vein opening was higher,while the usage and dosage of epinephrine during portal vein opening and vasoactive inotropic score after portal vein opening were lower in the CO-G group(P<0.05).Compared to the control group,serum inflammatory factors(interleukin-6 and tumor necrosis factor-α),cardiac troponin I,and N-terminal pro-brain natriuretic peptide were lower in the CO-G group after the operation(P<0.05).CONCLUSION CO-G hemodynamic management in pediatric living-donor LT decreases the incidence of early postoperative ALI due to hemodynamic stability through optimized fluid management and appropriate administration of vasopressors and inotropes.展开更多
Donor management is the key in the complex donation process,since up to 20%of organs of brain death donors(DBD)are lost due to hemodynamic instability.This challenge is made more difficult due to the lack of strong re...Donor management is the key in the complex donation process,since up to 20%of organs of brain death donors(DBD)are lost due to hemodynamic instability.This challenge is made more difficult due to the lack of strong recommendations on therapies for hemodynamic management in DBDs and more importantly to the epidemiologic changes in these donors who are becoming older and with more comorbidities(marginal donors).In the present manuscript we aimed at summarizing the available evidence on therapeutic strategies for hemodynamic management(focusing on vasoactive drugs)and monitoring(therapeutic goals).Evidence on management in elderly DBDs is also summarized.Donor management continues critical care but with different and specific therapeutic goals since the number of donor goals met is related to the number of organs retrieved and transplanted.Careful monitoring of selected parameters(possibly including serial echocardiography)is the clinical tool able to guarantee the achievement and maintaining of therapeutic goals.Despide worldwide differences,norepinephrine is the vasoactive of choice in most countries but,whenever higher doses(>0.2 mcg/kg/min)are needed,a second vasoactive drug(vasopressin)is advisable.Hormonal therapy(desmopressin,corticosteroid and thyroid hormone)are suggested in all DBDs independently of hemodynamic instability.In the single patient,therapeutic regimen(imprimis vasoactive drugs)should be chosen also according to the potential organs retrievable(i.e.heart vs liver and kidneys).展开更多
In recent years,the Internet of Things(IoT)technology has been considered one of the most attractive fields for researchers due to its aspirations and implications for society and life as a whole.The IoT environment c...In recent years,the Internet of Things(IoT)technology has been considered one of the most attractive fields for researchers due to its aspirations and implications for society and life as a whole.The IoT environment contains vast numbers of devices,equipment,and heterogeneous users who generate massive amounts of data.Furthermore,things’entry into and exit fromIoT systems occur dynamically,changing the topology and content of IoT networks very quickly.Therefore,managing IoT environments is among the most pressing challenges.This paper proposes an adaptive and dynamic scheme for managing IoT environments is proposed.This management scheme depends on the use of previous management methodologies,considering two main factors.The first factor is network status,which is determined in real-time.The second factor is a management method’s suitability according to its desired administration.To test the proposed management scheme,a simulation environment is created using NS3.The metrics used to measure the management scheme performance are bandwidth consumption,energy consumption,packet loss,throughput,delay,usage rate of individualmanagement techniques,and transformation.The simulation results prove that the proposed management scheme outperformed the individual 6LowPANSNMP,CoAP,and LWM2M management schemes.展开更多
There is increasing evidence that adequate donor management with a goal of optimization of organ function is essential to maximize the number of organs that can be procured.Therefore,identification of the cause of hem...There is increasing evidence that adequate donor management with a goal of optimization of organ function is essential to maximize the number of organs that can be procured.Therefore,identification of the cause of hemodynamic instability is crucial in order to direct the right therapy.Several donor management goals for better hemodynamic management including serial echocardiography can guide hemodynamic management in potential donors to increase both number and quality of donor hearts.展开更多
This presentation focuses on the complex issue of managing digital rights for long-term preservation. It describes the strategy and the methodology adopted within the SPAR project (French National Library), which rely...This presentation focuses on the complex issue of managing digital rights for long-term preservation. It describes the strategy and the methodology adopted within the SPAR project (French National Library), which rely on a special kind of knowledge-based system.展开更多
To solve the problem of delayed update of spectrum information(SI) in the database assisted dynamic spectrum management(DB-DSM), this paper studies a novel dynamic update scheme of SI in DB-DSM. Firstly, a dynamic upd...To solve the problem of delayed update of spectrum information(SI) in the database assisted dynamic spectrum management(DB-DSM), this paper studies a novel dynamic update scheme of SI in DB-DSM. Firstly, a dynamic update mechanism of SI based on spectrum opportunity incentive is established, in which spectrum users are encouraged to actively assist the database to update SI in real time. Secondly, the information update contribution(IUC) of spectrum opportunity is defined to describe the cost of accessing spectrum opportunity for heterogeneous spectrum users, and the profit of SI update obtained by the database from spectrum allocation. The process that the database determines the IUC of spectrum opportunity and spectrum user selects spectrum opportunity is mapped to a Hotelling model. Thirdly, the process of determining the IUC of spectrum opportunities is further modelled as a Stackelberg game by establishing multiple virtual spectrum resource providers(VSRPs) in the database. It is proved that there is a Nash Equilibrium in the game of determining the IUC of spectrum opportunities by VSRPs. Finally, an algorithm of determining the IUC based on a genetic algorithm is designed to achieve the optimal IUC. The-oretical analysis and simulation results show that the proposed method can quickly find the optimal solution of the IUC, and ensure that the spectrum resource provider can obtain the optimal profit of SI update.展开更多
The satellite-terrestrial networks possess the ability to transcend geographical constraints inherent in traditional communication networks,enabling global coverage and offering users ubiquitous computing power suppor...The satellite-terrestrial networks possess the ability to transcend geographical constraints inherent in traditional communication networks,enabling global coverage and offering users ubiquitous computing power support,which is an important development direction of future communications.In this paper,we take into account a multi-scenario network model under the coverage of low earth orbit(LEO)satellite,which can provide computing resources to users in faraway areas to improve task processing efficiency.However,LEO satellites experience limitations in computing and communication resources and the channels are time-varying and complex,which makes the extraction of state information a daunting task.Therefore,we explore the dynamic resource management issue pertaining to joint computing,communication resource allocation and power control for multi-access edge computing(MEC).In order to tackle this formidable issue,we undertake the task of transforming the issue into a Markov decision process(MDP)problem and propose the self-attention based dynamic resource management(SABDRM)algorithm,which effectively extracts state information features to enhance the training process.Simulation results show that the proposed algorithm is capable of effectively reducing the long-term average delay and energy consumption of the tasks.展开更多
Reverting to nature as a major arsenals in a universal fight against Climate Change impact and loss of biodiversity, the United Nations Convention to Combat Desertification (UNCCD), views sustainable Land use and Fore...Reverting to nature as a major arsenals in a universal fight against Climate Change impact and loss of biodiversity, the United Nations Convention to Combat Desertification (UNCCD), views sustainable Land use and Forest (the main crux of the Glasgow declaration 2021) as the way to go. Forest conservation, protection and management in the context of REDD+ would guarantee sustainable ecosystem and mitigate climate change impacts. At National and subnational levels, the Nigerian REDD+ readiness scheme holds out hope for environmental sustainability. This study throws light into the historical background of trends in land use forest change in Nigeria, and places Nigeria on a “red” stage 3 (Low Forest Cover, High Deforestation Rate-LFHD) status while maintaining optimism that with REDD+ properly implemented in Nigeria, Stage 4: Low forest cover, Low Deforestation Rates (LFLD) and Stage 5: Low forest cover, Negative Deforestation Rates (LFND) can be achieved by 2030 and 2050 respectively, if the trio of reforestation, afforestation and natural restoration is practiced as a matter of national policy and subnational implementation within the context of REDD+. Four (4) broad drivers of deforestation and forest degradation were identified as direct, indirect, pre-disposing and planned /unplanned. The paper concludes that a viable pathway to sustainable environmental management is appropriate monitoring and evaluation of land use and forest dynamics in the context of REDD+.展开更多
Water markets even though not perfect and require a lot of effort to establish are considered as a robust tool to address water management issues around the world. However, the existing literature does not provide an ...Water markets even though not perfect and require a lot of effort to establish are considered as a robust tool to address water management issues around the world. However, the existing literature does not provide an optimal water resource management policy. To create a perfect water market, the government needs to identify the potential number of suppliers/producers and consumers of water against various extraction/supply/production rates of water, i.e., to identify a supply and a demand curve for number of suppliers/producers of water against each production rate in economy. This article presents a theory which is practically applicable for an optimal dynamical water resource management policy (JEL H20, H23, H27).展开更多
With increasing population and changing demographics,food consumption has experienced a significant transition in quantity and quality.However,a dearth of knowledge remains regarding its environmental impacts and how ...With increasing population and changing demographics,food consumption has experienced a significant transition in quantity and quality.However,a dearth of knowledge remains regarding its environmental impacts and how it responds to demographic dynamics,particularly in emerging economies like China.Using the two-stage Quadratic Almost Demand System(QUAIDS)model,this study empirically examines the impact of demographic dynamics on food consumption and its environmental outcomes based on the provincial data from 2000 to 2020 in China.Under various scenarios,according to changes in demographics,we extend our analysis to project the long-term trend of food consumption and its environmental impacts,including greenhouse gas(GHG)emissions,water footprint(WF),and land appropriation(LA).The results reveal that an increase in the proportion of senior people significantly decreases the consumption of grain and livestock meat and increases the consumption of poultry,egg,and aquatic products,particularly for urban residents.Moreover,an increase in the proportion of males in the population leads to higher consumption of poultry and aquatic products.Correspondingly,in the current scenario of an increased aging population and sex ratio,it is anticipated that GHG emissions,WF,and LA are likely to decrease by 1.37,2.52,and 3.56%,respectively.More importantly,in the scenario adhering to the standards of nutritional intake according to the Dietary Guidelines for Chinese Residents in 2022,GHG emissions,WF,and LA in urban areas would increase by 12.78,20.94,and 18.32%,respectively.Our findings suggest that changing demographics should be considered when designing policies to mitigate the diet-environment-health trilemma and achieve sustainable food consumption.展开更多
Several research studies have proven that eliciting and predicting the impact of human activity on ecosystem services will be crucial to support stakeholders’ awareness and to decide how to interact with the environm...Several research studies have proven that eliciting and predicting the impact of human activity on ecosystem services will be crucial to support stakeholders’ awareness and to decide how to interact with the environment in a more sustainable manner. In this sense, the ecosystems known as road verges are particularly important because of their length and surface at an international scale, and their role in mitigating the damage done by roads. Plant pollination by insects is one of the most important ecosystem services. Because of its nature and the fact that they extend across a variety of landscapes, roadside can contribute to the maintenance of healthy ecosystems, under the condition of adapted management practices. This research is the first attempt to develop a System Dynamics-based aiming to estimate the ecological and economic impact of maintenance on the road verge pollination service in France. Maintenance strategies of road verges are simulated to compare their performance. The results show that there are ways to improve current maintenance strategies in terms of pollination value, but also that the model needs to consider other ecosystem services and synergistic effects that could further affect pollination to obtain more accurate estimations.展开更多
With the integration of ultrafast reflectivity and polarimetry probes,we observed carrier relaxation and spin dynamics induced by ultrafast laser excitation of Ni(111)single crystals.The carrier relaxation time within...With the integration of ultrafast reflectivity and polarimetry probes,we observed carrier relaxation and spin dynamics induced by ultrafast laser excitation of Ni(111)single crystals.The carrier relaxation time within the linear excitation range reveals that electron-phonon coupling and dissipation of photon energy into the bulk of the crystal take tens of picoseconds.On the other hand,the observed spin dynamics indicate a longer time of about 120 ps.To further understand how the lattice degree of freedom is coupled with these dynamics may require the integration of an ultrafast diffraction probe.展开更多
Identifying critical nodes or sets in large-scale networks is a fundamental scientific problem and one of the key research directions in the fields of data mining and network science when implementing network attacks,...Identifying critical nodes or sets in large-scale networks is a fundamental scientific problem and one of the key research directions in the fields of data mining and network science when implementing network attacks, defense, repair and control.Traditional methods usually begin from the centrality, node location or the impact on the largest connected component after node destruction, mainly based on the network structure.However, these algorithms do not consider network state changes.We applied a model that combines a random connectivity matrix and minimal low-dimensional structures to represent network connectivity.By using mean field theory and information entropy to calculate node activity,we calculated the overlap between the random parts and fixed low-dimensional parts to quantify the influence of node impact on network state changes and ranked them by importance.We applied this algorithm and the proposed importance algorithm to the overall analysis and stratified analysis of the C.elegans neural network.We observed a change in the critical entropy of the network state and by utilizing the proposed method we can calculate the nodes that indirectly affect muscle cells through neural layers.展开更多
The plug-in hybrid vehicles(PHEV)technology can effectively address the issues of poor dynamics and higher energy consumption commonly found in traditional mining dump trucks.Meanwhile,plug-in hybrid electric trucks c...The plug-in hybrid vehicles(PHEV)technology can effectively address the issues of poor dynamics and higher energy consumption commonly found in traditional mining dump trucks.Meanwhile,plug-in hybrid electric trucks can achieve excellent fuel economy through efficient energy management strategies(EMS).Therefore,a series hybrid system is constructed based on a 100-ton mining dump truck in this paper.And inspired by the dynamic programming(DP)algorithm,a predictive equivalent consumption minimization strategy(P-ECMS)based on the DP optimization result is proposed.Based on the optimal control manifold and the SOC reference trajectory obtained by the DP algorithm,the P-ECMS strategy performs real-time stage parameter optimization to obtain the optimal equivalent factor(EF).Finally,applying the equivalent consumption minimization strategy(ECMS)realizes real-time control.The simulation results show that the equivalent fuel consumption of the P-ECMS strategy under the experimentally collected mining cycle conditions is 150.8 L/100 km,which is 10.9%less than that of the common CDCS strategy(169.3 L/100 km),and achieves 99.47%of the fuel saving effect of the DP strategy(150 L/100 km).展开更多
This paper presents a mathematical model consisting of conservation and balance laws (CBL) of classical continuum mechanics (CCM) and ordered rate constitutive theories in Lagrangian description derived using entropy ...This paper presents a mathematical model consisting of conservation and balance laws (CBL) of classical continuum mechanics (CCM) and ordered rate constitutive theories in Lagrangian description derived using entropy inequality and the representation theorem for thermoviscoelastic solids (TVES) with rheology. The CBL and the constitutive theories take into account finite deformation and finite strain deformation physics and are based on contravariant deviatoric second Piola-Kirchhoff stress tensor and its work conjugate covariant Green’s strain tensor and their material derivatives of up to order m and n respectively. All published works on nonlinear dynamics of TVES with rheology are mostly based on phenomenological mathematical models. In rare instances, some aspects of CBL are used but are incorrectly altered to obtain mass, stiffness and damping matrices using space-time decoupled approaches. In the work presented in this paper, we show that this is not possible using CBL of CCM for TVES with rheology. Thus, the mathematical models used currently in the published works are not the correct description of the physics of nonlinear dynamics of TVES with rheology. The mathematical model used in the present work is strictly based on the CBL of CCM and is thermodynamically and mathematically consistent and the space-time coupled finite element methodology used in this work is unconditionally stable and provides solutions with desired accuracy and is ideally suited for nonlinear dynamics of TVES with memory. The work in this paper is the first presentation of a mathematical model strictly based on CBL of CCM and the solution of the mathematical model is obtained using unconditionally stable space-time coupled computational methodology that provides control over the errors in the evolution. Both space-time coupled and space-time decoupled finite element formulations are considered for obtaining solutions of the IVPs described by the mathematical model and are presented in the paper. Factors or the physics influencing dynamic response and dynamic bifurcation for TVES with rheology are identified and are also demonstrated through model problem studies. A simple model problem consisting of a rod (1D) of TVES material with memory fixed at one end and subjected to harmonic excitation at the other end is considered to study nonlinear dynamics of TVES with rheology, frequency response as well as dynamic bifurcation phenomenon.展开更多
文摘BACKGROUND In brain death donors(BDDs),donor management is the key in the complex donation process.Donor management goals,which are standards of care or clinical parameters,have been considered an acceptable barometer of successful donor management.AIM To test the hypothesis that aetiology of brain death could influence haemodynamic management in BDDs.METHODS Haemodynamic data(blood pressure,heart rate,central venous pressure,lactate,urine output,and vasoactive drugs)of BDDs were recorded on intensive care unit(ICU)admission and during the 6-h observation period(Time 1 at the beginning;Time 2 at the end).RESULTS The study population was divided into three groups according to the aetiology of brain death:Stroke(n=71),traumatic brain injury(n=48),and postanoxic encephalopathy(n=19).On ICU admission,BDDs with postanoxic encephalopathy showed the lowest values of systolic and diastolic blood pressure associated with higher values of heart rate and lactate and a higher need of norepinephrine and other vasoactive drugs.At the beginning of the 6-h period(Time 1),BDDs with postanoxic encephalopathy showed higher values of heart rate,lactate,and central venous pressure together with a higher need of other vasoactive drugs.CONCLUSION According to our data,haemodynamic management of BDDs is affected by the aetiology of brain death.BDDs with postanoxic encephalopathy have higher requirements for norepinephrine and other vasoactive drugs.
文摘The virtual enterprise will play a more and more im po rtant role in economy development. The virtual enterprise leader raises market a daptability and group cooperation ability through its dynamic management. Thus t he validity and efficiency of leader’s dynamic management determines the efficie ncy of the virtual enterprise operation, and the validity of the information flo w is one of the main factors. In this paper, the validity of the information flo w in the course of the leader’s dynamic management in the virtual enterprise is analyzed by using the economic searching theory and the information theory, and the possible ways to improve the validity and efficiency of leader’s dynamic man agement are indicated. Firstly, the basic concepts such as leader’s dynamic management, virtual enterpr ise, and its leader are defined. The dynamic management procedure for the virtua l enterprise leader is analyzed with the dynamic theory raised by Mowshowitz. Secondly, the model for the dynamic management of the virtual enterprise leader is constructed using multi-goal selection. The information flow validity for th e leader during the stages of the identification and the establishment is analyz ed with the economic searching theory and the information theory. Meanwhile, the value of the dynamic management policy is discussed with the information va lue theory. Finally, two ways to improve the validity of the information flow are obtained. The first way is to process the various kinds of information of the existing mem bers in the virtual enterprise for the future cooperative usage and to extend th e selective objects for the leader, and to make the detailed and clear mechanism of the object evaluation and selection (the market chance and the cooperative partner). The other way is to build the system of the effective transfer and process of the feedback information flow during the operation of the virtual ent erprise based on the information technology.
文摘The rapid economic development has promoted the construction of infrastructure,such as highways and water conservancy projects.The establishment of highways has facilitated people's lives and made the distance between regions shorter and shorter.However,the construction of highway engineering is a big project,which not only has a long cycle,but also has a high economic cost.During the construction process,a large number of construction materials and personnel will be applied.If the project cost management is not implemented for the highway construction,it will easily affect the final quality and profit of the entire project.This article expounds the significance of dynamic management and control of highway engineering cost,and analyzes the strategy of dynamic management and control of highway engineering cost.
文摘With the continuous improvement of urbanization level,the construction of municipal roads has received more attention.The rational application of dynamic management mode to the survey and design management of municipal roads is conducive to improve the survey and design management level of municipal roads and further realizing the optimization of the construction effect of municipal roads.In this paper,the various factors which are affecting the management of municipal road survey and design as well the principles of municipal road design were discussed.Further,the recommendation of the application strategy of dynamic management mode in municipal road survey and design management was proposed in this paper.
文摘BACKGROUND Acute lung injury(ALI)after liver transplantation(LT)may lead to acute respiratory distress syndrome,which is associated with adverse postoperative outcomes,such as prolonged hospital stay,high morbidity,and mortality.Therefore,it is vital to maintain hemodynamic stability and optimize fluid management.However,few studies have reported cardiac output-guided(CO-G)management in pediatric LT.AIM To investigate the effect of CO-G hemodynamic management on early postoperative ALI and hemodynamic stability during pediatric living donor LT.METHODS A total of 130 pediatric patients scheduled for elective living donor LT were enrolled as study participants and were assigned to the control group(65 cases)and CO-G group(65 cases).In the CO-G group,CO was considered the target for hemodynamic management.In the control group,hemodynamic management was based on usual perioperative care guided by central venous pressure,continuous invasive arterial pressure,urinary volume,etc.The primary outcome was early postoperative ALI.Secondary outcomes included other early postoperative pulmonary complications,readmission to the intense care unit(ICU)for pulmonary complications,ICU stay,hospital stay,and in-hospital mortality.RESULTS The incidence of early postoperative ALI was 27.7%in the CO-G group,which was significantly lower than that in the control group(44.6%)(P<0.05).During the surgery,the incidence of postreperfusion syndrome was lower in the CO-G group(P<0.05).The level of intraoperative positive fluid transfusions was lower and the rate of dobutamine use before portal vein opening was higher,while the usage and dosage of epinephrine during portal vein opening and vasoactive inotropic score after portal vein opening were lower in the CO-G group(P<0.05).Compared to the control group,serum inflammatory factors(interleukin-6 and tumor necrosis factor-α),cardiac troponin I,and N-terminal pro-brain natriuretic peptide were lower in the CO-G group after the operation(P<0.05).CONCLUSION CO-G hemodynamic management in pediatric living-donor LT decreases the incidence of early postoperative ALI due to hemodynamic stability through optimized fluid management and appropriate administration of vasopressors and inotropes.
文摘Donor management is the key in the complex donation process,since up to 20%of organs of brain death donors(DBD)are lost due to hemodynamic instability.This challenge is made more difficult due to the lack of strong recommendations on therapies for hemodynamic management in DBDs and more importantly to the epidemiologic changes in these donors who are becoming older and with more comorbidities(marginal donors).In the present manuscript we aimed at summarizing the available evidence on therapeutic strategies for hemodynamic management(focusing on vasoactive drugs)and monitoring(therapeutic goals).Evidence on management in elderly DBDs is also summarized.Donor management continues critical care but with different and specific therapeutic goals since the number of donor goals met is related to the number of organs retrieved and transplanted.Careful monitoring of selected parameters(possibly including serial echocardiography)is the clinical tool able to guarantee the achievement and maintaining of therapeutic goals.Despide worldwide differences,norepinephrine is the vasoactive of choice in most countries but,whenever higher doses(>0.2 mcg/kg/min)are needed,a second vasoactive drug(vasopressin)is advisable.Hormonal therapy(desmopressin,corticosteroid and thyroid hormone)are suggested in all DBDs independently of hemodynamic instability.In the single patient,therapeutic regimen(imprimis vasoactive drugs)should be chosen also according to the potential organs retrievable(i.e.heart vs liver and kidneys).
基金funded by the Taif University Researchers Supporting Project No.(TURSP-2020/60),Taif University,Taif,Saudi Arabia.
文摘In recent years,the Internet of Things(IoT)technology has been considered one of the most attractive fields for researchers due to its aspirations and implications for society and life as a whole.The IoT environment contains vast numbers of devices,equipment,and heterogeneous users who generate massive amounts of data.Furthermore,things’entry into and exit fromIoT systems occur dynamically,changing the topology and content of IoT networks very quickly.Therefore,managing IoT environments is among the most pressing challenges.This paper proposes an adaptive and dynamic scheme for managing IoT environments is proposed.This management scheme depends on the use of previous management methodologies,considering two main factors.The first factor is network status,which is determined in real-time.The second factor is a management method’s suitability according to its desired administration.To test the proposed management scheme,a simulation environment is created using NS3.The metrics used to measure the management scheme performance are bandwidth consumption,energy consumption,packet loss,throughput,delay,usage rate of individualmanagement techniques,and transformation.The simulation results prove that the proposed management scheme outperformed the individual 6LowPANSNMP,CoAP,and LWM2M management schemes.
文摘There is increasing evidence that adequate donor management with a goal of optimization of organ function is essential to maximize the number of organs that can be procured.Therefore,identification of the cause of hemodynamic instability is crucial in order to direct the right therapy.Several donor management goals for better hemodynamic management including serial echocardiography can guide hemodynamic management in potential donors to increase both number and quality of donor hearts.
文摘This presentation focuses on the complex issue of managing digital rights for long-term preservation. It describes the strategy and the methodology adopted within the SPAR project (French National Library), which rely on a special kind of knowledge-based system.
文摘To solve the problem of delayed update of spectrum information(SI) in the database assisted dynamic spectrum management(DB-DSM), this paper studies a novel dynamic update scheme of SI in DB-DSM. Firstly, a dynamic update mechanism of SI based on spectrum opportunity incentive is established, in which spectrum users are encouraged to actively assist the database to update SI in real time. Secondly, the information update contribution(IUC) of spectrum opportunity is defined to describe the cost of accessing spectrum opportunity for heterogeneous spectrum users, and the profit of SI update obtained by the database from spectrum allocation. The process that the database determines the IUC of spectrum opportunity and spectrum user selects spectrum opportunity is mapped to a Hotelling model. Thirdly, the process of determining the IUC of spectrum opportunities is further modelled as a Stackelberg game by establishing multiple virtual spectrum resource providers(VSRPs) in the database. It is proved that there is a Nash Equilibrium in the game of determining the IUC of spectrum opportunities by VSRPs. Finally, an algorithm of determining the IUC based on a genetic algorithm is designed to achieve the optimal IUC. The-oretical analysis and simulation results show that the proposed method can quickly find the optimal solution of the IUC, and ensure that the spectrum resource provider can obtain the optimal profit of SI update.
基金supported by the National Key Research and Development Plan(No.2022YFB2902701)the key Natural Science Foundation of Shenzhen(No.JCYJ20220818102209020).
文摘The satellite-terrestrial networks possess the ability to transcend geographical constraints inherent in traditional communication networks,enabling global coverage and offering users ubiquitous computing power support,which is an important development direction of future communications.In this paper,we take into account a multi-scenario network model under the coverage of low earth orbit(LEO)satellite,which can provide computing resources to users in faraway areas to improve task processing efficiency.However,LEO satellites experience limitations in computing and communication resources and the channels are time-varying and complex,which makes the extraction of state information a daunting task.Therefore,we explore the dynamic resource management issue pertaining to joint computing,communication resource allocation and power control for multi-access edge computing(MEC).In order to tackle this formidable issue,we undertake the task of transforming the issue into a Markov decision process(MDP)problem and propose the self-attention based dynamic resource management(SABDRM)algorithm,which effectively extracts state information features to enhance the training process.Simulation results show that the proposed algorithm is capable of effectively reducing the long-term average delay and energy consumption of the tasks.
文摘Reverting to nature as a major arsenals in a universal fight against Climate Change impact and loss of biodiversity, the United Nations Convention to Combat Desertification (UNCCD), views sustainable Land use and Forest (the main crux of the Glasgow declaration 2021) as the way to go. Forest conservation, protection and management in the context of REDD+ would guarantee sustainable ecosystem and mitigate climate change impacts. At National and subnational levels, the Nigerian REDD+ readiness scheme holds out hope for environmental sustainability. This study throws light into the historical background of trends in land use forest change in Nigeria, and places Nigeria on a “red” stage 3 (Low Forest Cover, High Deforestation Rate-LFHD) status while maintaining optimism that with REDD+ properly implemented in Nigeria, Stage 4: Low forest cover, Low Deforestation Rates (LFLD) and Stage 5: Low forest cover, Negative Deforestation Rates (LFND) can be achieved by 2030 and 2050 respectively, if the trio of reforestation, afforestation and natural restoration is practiced as a matter of national policy and subnational implementation within the context of REDD+. Four (4) broad drivers of deforestation and forest degradation were identified as direct, indirect, pre-disposing and planned /unplanned. The paper concludes that a viable pathway to sustainable environmental management is appropriate monitoring and evaluation of land use and forest dynamics in the context of REDD+.
文摘Water markets even though not perfect and require a lot of effort to establish are considered as a robust tool to address water management issues around the world. However, the existing literature does not provide an optimal water resource management policy. To create a perfect water market, the government needs to identify the potential number of suppliers/producers and consumers of water against various extraction/supply/production rates of water, i.e., to identify a supply and a demand curve for number of suppliers/producers of water against each production rate in economy. This article presents a theory which is practically applicable for an optimal dynamical water resource management policy (JEL H20, H23, H27).
基金This work was supported by the Qinchuangyuan Project of Shaanxi Province,China(QCYRCXM-2022-145)the Major Project of the Key Research Base of Humanities and Social Sciences of the Ministry of Education,China(22JJD790052)+1 种基金the Chinese Universities Scientific Fund(Z1010422003)the National Natural Science Foundation of China(72373117).
文摘With increasing population and changing demographics,food consumption has experienced a significant transition in quantity and quality.However,a dearth of knowledge remains regarding its environmental impacts and how it responds to demographic dynamics,particularly in emerging economies like China.Using the two-stage Quadratic Almost Demand System(QUAIDS)model,this study empirically examines the impact of demographic dynamics on food consumption and its environmental outcomes based on the provincial data from 2000 to 2020 in China.Under various scenarios,according to changes in demographics,we extend our analysis to project the long-term trend of food consumption and its environmental impacts,including greenhouse gas(GHG)emissions,water footprint(WF),and land appropriation(LA).The results reveal that an increase in the proportion of senior people significantly decreases the consumption of grain and livestock meat and increases the consumption of poultry,egg,and aquatic products,particularly for urban residents.Moreover,an increase in the proportion of males in the population leads to higher consumption of poultry and aquatic products.Correspondingly,in the current scenario of an increased aging population and sex ratio,it is anticipated that GHG emissions,WF,and LA are likely to decrease by 1.37,2.52,and 3.56%,respectively.More importantly,in the scenario adhering to the standards of nutritional intake according to the Dietary Guidelines for Chinese Residents in 2022,GHG emissions,WF,and LA in urban areas would increase by 12.78,20.94,and 18.32%,respectively.Our findings suggest that changing demographics should be considered when designing policies to mitigate the diet-environment-health trilemma and achieve sustainable food consumption.
文摘Several research studies have proven that eliciting and predicting the impact of human activity on ecosystem services will be crucial to support stakeholders’ awareness and to decide how to interact with the environment in a more sustainable manner. In this sense, the ecosystems known as road verges are particularly important because of their length and surface at an international scale, and their role in mitigating the damage done by roads. Plant pollination by insects is one of the most important ecosystem services. Because of its nature and the fact that they extend across a variety of landscapes, roadside can contribute to the maintenance of healthy ecosystems, under the condition of adapted management practices. This research is the first attempt to develop a System Dynamics-based aiming to estimate the ecological and economic impact of maintenance on the road verge pollination service in France. Maintenance strategies of road verges are simulated to compare their performance. The results show that there are ways to improve current maintenance strategies in terms of pollination value, but also that the model needs to consider other ecosystem services and synergistic effects that could further affect pollination to obtain more accurate estimations.
基金Project supported by the National Key R&D Program of China (Grant Nos. 2022YFA1604402 and 2022YFA1604403)the National Natural Science Foundation of China (NSFC) (Grant No. 11721404)+3 种基金the Shanghai Rising-Star Program (Grant No. 21QA1406100)the Technology Innovation Action Plan of the Science and Technology Commission of Shanghai Municipality (Grant No. 20JC1416000)support by the Air Force Office of Scientific Research (AFOSR) (Grant No. FA9550-20-10139)the Texas A&M Engineering Experimental Station (TEES)
文摘With the integration of ultrafast reflectivity and polarimetry probes,we observed carrier relaxation and spin dynamics induced by ultrafast laser excitation of Ni(111)single crystals.The carrier relaxation time within the linear excitation range reveals that electron-phonon coupling and dissipation of photon energy into the bulk of the crystal take tens of picoseconds.On the other hand,the observed spin dynamics indicate a longer time of about 120 ps.To further understand how the lattice degree of freedom is coupled with these dynamics may require the integration of an ultrafast diffraction probe.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.72071153 and 72231008)Laboratory of Science and Technology on Integrated Logistics Support Foundation (Grant No.6142003190102)the Natural Science Foundation of Shannxi Province (Grant No.2020JM486)。
文摘Identifying critical nodes or sets in large-scale networks is a fundamental scientific problem and one of the key research directions in the fields of data mining and network science when implementing network attacks, defense, repair and control.Traditional methods usually begin from the centrality, node location or the impact on the largest connected component after node destruction, mainly based on the network structure.However, these algorithms do not consider network state changes.We applied a model that combines a random connectivity matrix and minimal low-dimensional structures to represent network connectivity.By using mean field theory and information entropy to calculate node activity,we calculated the overlap between the random parts and fixed low-dimensional parts to quantify the influence of node impact on network state changes and ranked them by importance.We applied this algorithm and the proposed importance algorithm to the overall analysis and stratified analysis of the C.elegans neural network.We observed a change in the critical entropy of the network state and by utilizing the proposed method we can calculate the nodes that indirectly affect muscle cells through neural layers.
文摘The plug-in hybrid vehicles(PHEV)technology can effectively address the issues of poor dynamics and higher energy consumption commonly found in traditional mining dump trucks.Meanwhile,plug-in hybrid electric trucks can achieve excellent fuel economy through efficient energy management strategies(EMS).Therefore,a series hybrid system is constructed based on a 100-ton mining dump truck in this paper.And inspired by the dynamic programming(DP)algorithm,a predictive equivalent consumption minimization strategy(P-ECMS)based on the DP optimization result is proposed.Based on the optimal control manifold and the SOC reference trajectory obtained by the DP algorithm,the P-ECMS strategy performs real-time stage parameter optimization to obtain the optimal equivalent factor(EF).Finally,applying the equivalent consumption minimization strategy(ECMS)realizes real-time control.The simulation results show that the equivalent fuel consumption of the P-ECMS strategy under the experimentally collected mining cycle conditions is 150.8 L/100 km,which is 10.9%less than that of the common CDCS strategy(169.3 L/100 km),and achieves 99.47%of the fuel saving effect of the DP strategy(150 L/100 km).
文摘This paper presents a mathematical model consisting of conservation and balance laws (CBL) of classical continuum mechanics (CCM) and ordered rate constitutive theories in Lagrangian description derived using entropy inequality and the representation theorem for thermoviscoelastic solids (TVES) with rheology. The CBL and the constitutive theories take into account finite deformation and finite strain deformation physics and are based on contravariant deviatoric second Piola-Kirchhoff stress tensor and its work conjugate covariant Green’s strain tensor and their material derivatives of up to order m and n respectively. All published works on nonlinear dynamics of TVES with rheology are mostly based on phenomenological mathematical models. In rare instances, some aspects of CBL are used but are incorrectly altered to obtain mass, stiffness and damping matrices using space-time decoupled approaches. In the work presented in this paper, we show that this is not possible using CBL of CCM for TVES with rheology. Thus, the mathematical models used currently in the published works are not the correct description of the physics of nonlinear dynamics of TVES with rheology. The mathematical model used in the present work is strictly based on the CBL of CCM and is thermodynamically and mathematically consistent and the space-time coupled finite element methodology used in this work is unconditionally stable and provides solutions with desired accuracy and is ideally suited for nonlinear dynamics of TVES with memory. The work in this paper is the first presentation of a mathematical model strictly based on CBL of CCM and the solution of the mathematical model is obtained using unconditionally stable space-time coupled computational methodology that provides control over the errors in the evolution. Both space-time coupled and space-time decoupled finite element formulations are considered for obtaining solutions of the IVPs described by the mathematical model and are presented in the paper. Factors or the physics influencing dynamic response and dynamic bifurcation for TVES with rheology are identified and are also demonstrated through model problem studies. A simple model problem consisting of a rod (1D) of TVES material with memory fixed at one end and subjected to harmonic excitation at the other end is considered to study nonlinear dynamics of TVES with rheology, frequency response as well as dynamic bifurcation phenomenon.
