Influence of the time delay of signal transmission on synchronization conditions in drive-response systems

Conditions for complete and lag synchronizations in drive-response systems are considered under the unified framework of generalized synchronization. The question is addressed that whether the synchronization conditions achieving complete synchronization is still valid for lag synchronization when the time delay of signal transmission between the drive and response systems increases from 0. Theoretical and numerical results show that whether the synchronization conditions is stable for the influence of the time delay of signal transmission depends on a particular form of equilibria of the drive and response systems. Furthermore, it seems that the less the number of the equilibria of the drive system, the more likely the synchronization conditions are stable for the time delay of signal trans- mission.

Efficient computation for dynamic responses of systems with time-varying characteristics

Based on Neumman series and epsilon-algorithm, an efficient computation for dynamic responses of systems with arbitrary time-varying characteristics is investigated. Avoiding the calculation for the inverses of the equivalent stiffness matrices in each time step, the computation effort of the proposed method is reduced compared with the full analysis of Newmark method. The validity and applications of the proposed method are illustrated by a 4-DOF spring-mass system with periodical time-varying stiffness properties and a truss structure with arbitrary time-varying lumped mass. It shows that good approximate results can be obtained by the proposed method compared with the responses obtained by the full analysis of Newmark method.

The Application of Information Systems to Improve Ambulance Response Times in the UK

Emergency ambulance services in the UK are tasked with providing pre-hospital patient care and clinical services with a target response time between call connect to on-scene attendance.In 2017,NHS England introduced four new response time categories based on patient needs.The most challenging is to be on-scene for a life-threatening situation within seven minutes of the call being connected when such calls are random in terms of time and place throughout a large territory.Recent evidence indicates emergency ambulance services regularly fall short of achieving the target ambulance response times set by the National Health Service(NHS).To achieve these targets,they need to undertake transformational change and apply statistical,operations research and artificial intelligence techniques in the form of five separate modules covering demand forecasting,plus locate,allocate,dispatch,monitoring and re-deployment of resources.These modules should be linked in real-time employing a data warehouse to minimise computational data and generate accurate,meaningful and timely decisions ensuring patients receive an appropriate and timely response.A simulation covering a limited geographical area,time and operational data concluded that this form of integration of the five modules provides accurate and timely data upon which to make decisions that effectively improve ambulance response times.

Prescribed Performance Tracking Control of Time-Delay Nonlinear Systems With Output Constraints

The problem of prescribed performance tracking control for unknown time-delay nonlinear systems subject to output constraints is dealt with in this paper. In contrast with related works, only the most fundamental requirements, i.e., boundedness and the local Lipschitz condition, are assumed for the allowable time delays. Moreover, we focus on the case where the reference is unknown beforehand, which renders the standard prescribed performance control designs under output constraints infeasible. To conquer these challenges, a novel robust prescribed performance control approach is put forward in this paper.Herein, a reverse tuning function is skillfully constructed and automatically generates a performance envelop for the tracking error. In addition, a unified performance analysis framework based on proof by contradiction and the barrier function is established to reveal the inherent robustness of the control system against the time delays. It turns out that the system output tracks the reference with a preassigned settling time and good accuracy,without constraint violations. A comparative simulation on a two-stage chemical reactor is carried out to illustrate the above theoretical findings.

Optimal Multi-Timescale Scheduling of Integrated Energy Systems with Hybrid Energy Storage System Based on Lyapunov Optimization

The economic operation of integrated energy system(IES)faces new challenges such as multi-timescale characteristics of heterogeneous energy sources,and cooperative operation of hybrid energy storage system(HESS).To this end,this paper investigates the multi-timescale rolling opti-mization problem for IES integrated with HESS.Firstly,the architecture of IES with HESS is established,a comparative analysis is conducted to evaluate the advantages of the HESS over a single energy storage system(SESS)in stabilizing power fluctuations.Secondly,the dayahead and real-time scheduling cost functions of IES are established,the day-ahead scheduling mainly depends on operation costs of the components in IES,the real-time optimal scheduling adopts the Lya-punov optimization method to schedule the battery and hydrogen energy storage in each time slot,so as to minimize the real-time average scheduling operation cost,and the problem of day-ahead and real-time scheduling error,which caused by the uncertainty of the energy storage is solved by online optimization.Finally,the proposed model is verified to reduce the scheduling operation cost and the dispatching error by performing an arithmetic example analysis of the IES in Shanghai,which provides a reference for the safe and stable operation of the IES.

Systemic Inflammation Response Index and weight loss as prognostic factors in metastatic pancreatic cancer: A concept study from the PANTHEIA-SEOM trial

BACKGROUND The prognostic value of the Systemic Inflammation Response Index(SIRI)in advanced pancreatic cancer is recognized,but its correlation with patients´nutritional status and outcomes remains unexplored.AIM To study the prognostic significance of SIRI and weight loss in metastatic pancreatic cancer.METHODS The PANTHEIA-Spanish Society of Medical Oncology(SEOM)study is a multicentric(16 Spanish hospitals),observational,longitudinal,non-interventional initiative,promoted by the SEOM Real World-Evidence work group.This pilot study sought to analyze the association between weight loss and inflammatory status as defined by SIRI.The cohort stems from a proof-of-concept pilot study conducted at one of the coordinating centers.Patients with pathologically confirmed metastatic pancreatic adenocarcinoma,treated from January 2020 to January 2023,were included.The index was calculated using the product of neutrophil and monocyte counts,divided by lymphocyte counts,obtained within 15 days before initiation chemotherapy.This study evaluated associations between overall survival(OS),SIRI and weight loss.RESULTS A total of 50 patients were included.66%of these patients were male and the median age was 66 years.Metastasis sites:36%liver,12%peritoneal carcinomatosis,10%lung,and 42%multiple locations.Regarding the first line palliative chemotherapy treatments:50%received gemcitabine plus nab-paclitaxel;28%,modified fluorouracil,leucovorin,irinotecan and oxaliplatin,and 16%were administered gemcitabine.42%had a weight loss>5%in the three months(mo)preceding diagnosis.21 patients with a SIRI≥2.3×10^(3)/L exhibited a trend towards a lower median OS compared to those with a SIRI<2.3×10^(3)/L(4 vs 18 mo;P<0.000).Among 21 patients with>5%weight loss before diagnosis,the median OS was 6 mo,in contrast to 19 mo for those who did not experience such weight loss(P=0.003).Patients with a weight loss>5%showed higher SIRI levels.This difference was statistically significant(P<0.000).For patients with a SIRI<2.3×10^(3)/L,those who did not lose>5%of their weight had an OS of 20 mo,compared to 11 mo for those who did(P<0.001).No association was found between carbohydrate antigen 19-9 levels≥1000 U/mL and weight loss.CONCLUSION A higher SIRI was correlated with decreased survival rates in patients with metastatic pancreatic cancer and associated with weight loss.An elevated SIRI is suggested as a predictor of survival,emphasizing the need for prospective validation in the upcoming PANTHEIA-SEOM study.

Preoperative systemic inflammatory response index as a prognostic marker for distal cholangiocarcinoma after pancreatoduodenectomy

BACKGROUND The relationship between preoperative inflammation status and tumorigenesis as well as tumor progression is widely acknowledged.AIM To assess the prognostic significance of preoperative inflammatory biomarkers in patients with distal cholangiocarcinoma(dCCA)who underwent pancreat-oduodenectomy(PD).METHODS This single-center study included 216 patients with dCCA after PD between January 1,2011,and December 31,2022.The individuals were categorized into two sets based on their systemic inflammatory response index(SIRI)levels:A low SIRI group(SIRI<1.5,n=123)and a high SIRI group(SIRI≥1.5,n=93).Inflam-matory biomarkers were evaluated for predictive accuracy using receiver operating characteristic curves.Both univariate and multivariate Cox proportional hazards analyses were performed to estimate SIRI for overall survival(OS)and recurrence-free survival(RFS).RESULTS The study included a total of 216 patients,with 58.3%being male and a mean age of 65.6±9.6 years.123 patients were in the low SIRI group and 93 were in the high SIRI group after PD for dCCA.SIRI had an area under the curve value of 0.674 for diagnosing dCCA,showing better performance than other inflammatory biomarkers.Multivariate analysis indicated that having a SIRI greater than 1.5 independently increased the risk of dCCA following PD,leading to lower OS[hazard ratios(HR)=1.868,P=0.006]and RFS(HR=0.949,P<0.001).Additionally,survival analysis indicated a significantly better prognosis for patients in the low SIRI group(P<0.001).CONCLUSION It is determined that a high SIRI before surgery is a significant risk factor for dCCA after PD.

Systemic inflammatory response index is a predictor of prognosis in gastric cancer patients: Retrospective cohort and meta-analysis

BACKGROUND The systemic inflammatory response index(SIRI)has been demonstrated to make a significant difference in assessing the prognosis of patients with different solid neoplasms.However,research is needed to ascertain the accuracy and reliability of applying the SIRI to patients who undergo robotic radical gastric cancer sur-gery.AIM To validate the applicability of the SIRI in assessing the survival of gastric cancer patients and evaluate the clinical contribution of preoperative SIRI levels to predicting long-term tumor outcomes in patients,who received robotic radical gastric cancer surgery.METHODS Initially,an exhaustive retrieval was performed in the PubMed,the Cochrane Library,EMBASE,Web of Science,and Scopus databases to identify relevant studies.Subsequently,a meta-analysis was executed on 6 cohort studies iden-tifying the value of the SIRI in assessing the survival of gastric cancer patients.Additionally,the clinical data of 161 patients undergoing robotic radical gastric cancer surgery were retrospectively analyzed to evaluate their clinicopathological characteristics and relevant laboratory indicators.The association between preoperative SIRI levels and 5-year overall survival(OS)and disease-free survival(DFS)was assessed.RESULTS The findings demonstrated an extensive connection between SIRI values and the outcome of patients with gastric cancer.Preoperative SIRI levels were identified as an independent hazard feature for both OS and DFS among those who received robotic surgery for gastric cancer.SIRI levels in gastric cancer patients were observed to be associated with the presence of comorbidities,T-stage,carcinoembryonic antigen levels,the development of early serious postoperative complications,and the rate of lymph node metastasis.CONCLUSION SIRI values are correlated with adverse in the gastric cancer population and have the potential to be utilized in predicting long-term oncological survival in patients who undergo robotic radical gastric cancer surgery.

Numerical Simulation of Dynamic Response of Towed Systems

In this paper, the dynamic response of undersea -+towed systems is numerically simulated. A two body towed system is especially considered in detail. The factors influencing the heave of towed-bodies, such as the weight of the towed-body (in sea water), the length and the weight (in sea water) per unit length of the cable between towed-bodies and towing ship, are investigated in detail. Calculations show that the two-body towed system can greatly increases the stability of the towed system.

Hepatocellular carcinoma Liver Imaging Reporting and Data Systems treatment response assessment: Lessons learned and future directions

Hepatocellular carcinoma(HCC)is a leading cause of morbidity and mortality worldwide,with rising clinical and economic burden as incidence increases.There are a multitude of evolving treatment options,including locoregional therapies which can be used alone,in combination with each other,or in combination with systemic therapy.These treatment options have shown to be effective in achieving remission,controlling tumor progression,improving disease free and overall survival in patients who cannot undergo resection and providing a bridge to transplant by debulking tumor burden to downstage patients.Following locoregional therapy(LRT),it is crucial to provide treatment response assessment to guide management and liver transplant candidacy.Therefore,Liver Imaging Reporting and Data Systems(LI-RADS)Treatment Response Algorithm(TRA)was created to provide a standardized assessment of HCC following LRT.LIRADS TRA provides a step by step approach to evaluate each lesion independently for accurate tumor assessment.In this review,we provide an overview of different locoregional therapies for HCC,describe the expected post treatment imaging appearance following treatment,and review the LI-RADS TRA with guidance for its application in clinical practice.Unique to other publications,we will also review emerging literature supporting the use of LI-RADS for assessment of HCC treatment response after LRT.

Approximate analysis method for displacement responses of structures with active variable stiffness systems

The performance of structures with active variable stiffness (AVS) systems exhibits strong nonlinearity due to the variety with time of the stiffness of each storey unit,in which the AVS system is installed.Hence,the classical dynamic analysis method for linear structures,such as the mode-superposition method,is not applicable to structures with AVS systems.In this paper,an approximate analysis method is proposed for displacement responses of structures with AVS systems.Firstly,an equivalent relationship between single-degree-of-freedom (SDOF) structures equipped with AVS systems and so-called fictitious linear structures is established.Then,an approximate mode-superposition (AMS) method is presented for multi-degree-of-freedom (MDOF) structures equipped with AVS systems.The accuracy of this method is investigated through extensive parametrical study using different types of earthquake excitations,and some modification is made to the method. Numerical calculation results indicate that the modified AMS method is effective for estimating the maximum displacements relative to the ground and the maximum interstorey drifts of MDOF structures equipped with AVS systems.

Coronavirus disease 2019 (COVID-19) pandemic: how countries shouldbuild more resilient health systems for preparedness and response

Objective: A resilient health system plays a crucial role in pandemic preparedness and response. Althoughthe World Health Organization (WHO) has required all states parties to strengthen core capacities to respondto public health emergencies under the International Health Regulations (2005), the actions of most countriesto combating coronavirus disease 2019 (COVID-19) has showed that they are not well-prepared. This crosssectionalstudy aimed to examine the health system resilience of selected countries and analyze their strategiesand measures in response to the COVID-19 pandemic.Methods: This study selected five countries including the Iran, Japan, Republic of Korea (South Korea), the U.K.,and the U.S., based on the severity of the national epidemic, the geographical location, and the developmentlevel. Cumulative number of death cases derived from WHO COVID-19 dashboard was used to measure theseverity of the impact of the pandemic in each country;WHO State Parties Self-Assessment Annual Reporting (SPAR)Scores and Global Health Security (GHS) Index were applied to measure the national health system resilience;and research articles and press materials were summarized to identify the strategies and measures adopted bycountries during response to COVID-19. This study applied the resilient health systems framework to analyzehealth system resilience in the selected countries from five dimensions, including awareness, diversity, selfregulation,integration and adaptation.Results: The SPAR Scores and GHS Index of the four developed countries, Japan, South Korea, the U.K. and theU.S. were above the global and regional averages;the SPAR Scores of Iran were above the global average whilethe GHI Index lain below the global average. In terms of response strategies, Japan, the U.K. and the U.S. investedmore health resources in the treatment of severe patients, while South Korea and Iran had adopted a strategyof extensive testing and identification of suspected patients. In terms of specific measures, all the five countriesadopted measures such as restrictions on entry and international travel, closure of schools and industries,lockdown and quarantine. Nevertheless, the effectiveness of implementing these measures varied acrosscountries, based on the response strategies.Conclusion: Although SPAR Scores and GHS Index have evaluated the national core capacities for preparednessand response, the actions to cope with the COVID-19 pandemic has revealed the fact that most countries stilldo not build resilient health systems in response to public health emergencies. Health system strengtheningand health security efforts should be pursued in tandem, as part of the same mutually reinforcing approach todeveloping resilient health systems.

A GIS-Based Decision Support System for Reducing Air Ambulance Response Times: A Case Study on Public Schools in Jeddah City

In injuries reducing ambulance response time (time from injury to hospital arrival) is an important factor for saving people’s lives. Helicopter emergency medical services can reduce out-of-hospital transport times because of their high speed and their ability to travel in straight paths?unlike ground ambulance which are restricted to road network paths, as well as the ability toaccess rural or remote area injuries that are difficult to reach by ground ambulance. GIS technology aids air ambulance movement planning to reduce out-of-hospital response time based on mathematical and geographic models to support decision making which is necessary from out-of-hospital care providers. The goal of this study is to use GIS to develop an efficient DSS to outline where air ambulance can reduce response times, by using spatial analysis tools to create Euclidean distance and direction zones around receiving hospitals. The study concludes that GIS technology can be used to develop an efficient DSS to outline where air ambulance can reduce response times, by creating surfaces of Euclidean allocation, direction, and distance that can be used to improve initial response times for the civil defense air rescue and air ambulance services.

EXACT SOLUTIONS FOR STATIONARY RESPONSES OF SEVERAL CLASSES OF NONLINEAR SYSTEMS TO PARAMETRIC AND/OR EXTERNAL WHITE NOISE EXCITATIONS

The exact solutions for stationary responses of one class of the second order and three classes of higher order nonlinear systems to parametric and/or external while noise excitations are constructed by using Fokkcr-Planck-Kolmogorov et/ualion approach. The conditions for the existence and uniqueness and the behavior of the solutions are discussed. All the systems under consideration are characterized by the dependence ofnonconservative fqrces on the first integrals of the corresponding conservative systems and arc catted generalized-energy-dependent f G.E.D.) systems. It is shown taht for each of the four classes of G.E.D. nonlinear stochastic systems there is a family of non-G.E.D. systems which are equivalent to the G.E.D. system in the sense of having identical stationary solution. The way to find the equivalent stochastic systems for a given G.E.D. system is indicated and. as an example, the equivalent stochastic systems for the second order G.E. D. nonlinear stochastic system are given. It is pointed out and illustrated with example that the exact stationary solutions for many non-G.E.D. nonlinear stochastic systems may he found by searching the equivalent G.E.D. systems.

The Response Time Analysis of Digital Broadcasting System

Digital broadcasting system has become a high-light of research on computer application. To respond to the changes of the playbill in the broadcasting system in real time, the response time of the system must be studied. There is scarcely the research on this area currently. The influence factors in the response time are analyzed; the model on the response time of the system service is built; how the influence factors affect the response time of the system service is validated; and four improvement measures are proposed to minimize the response time of system service.

Impulsive Predator-Prey Dynamic Systems with Beddington-DeAngelis Type Functional Response on the Unification of Discrete and Continuous Systems

In this study, the impulsive predator-prey dynamic systems on time scales calculus are studied. When the system has periodic solution is investigated, and three different conditions have been found, which are necessary for the periodic solution of the predator-prey dynamic systems with Beddington-DeAngelis type functional response. For this study the main tools are time scales calculus and coincidence degree theory. Also the findings are beneficial for continuous case, discrete case and the unification of both these cases. Additionally, unification of continuous and discrete case is a good example for the modeling of the life cycle of insects.

Tangent response in coupled dynamical systems

We construct new unidirectional coupling schemes for autonomous and nonautonomous drive systems, respectively. Each of these schemes makes the state of the response system asymptotically approach the first-order derivative of the state of the driver. From the point of view of geometry, the first-order derivative of the state of the driver can be viewed as a tangent vector of the trajectory of the driver, so the proposed schemes are named tangent response schemes. Numerical simulations of the Lorenz system and the forced Duffing oscillator verify the validity of the tangent response schemes. We further point out that the tangent response can be interpreted as a special kind of generalised synchronisation, thereby explaining why the response system can exhibit rich geometrical structures in its state space.

EXISTENCE OF PERIODIC SOLUTIONS TO A SYSTEM WITH FUNCTIONAL RESPONSE ON TIME SCALES

This paper investigates the existence of periodic solutions of a three-species food-chain diffusive system with Beddington-DeAngelis functional responses and time delays in a two-patch environment on time scales. By using a continuation theorem based on coincidence degree theory, we obtain sufficient criteria for the existence of periodic solutions for the system. Moreover, when the time scale T is chosen as R or Z, the existence of the periodic solutions of the corresponding continuous and discrete models follows. Therefore, the method is unified to provide the existence of the desired solutions for continuous differential equations and discrete difference equations.

A Novel Approach for Evaluating Nonstationary Response of Dynamic Systems to Stochastic Excitation

The transient state of a dynamic system,such as offshore structures,to random excitation is always nonstationary.Many studies have contributed to evaluating response covariances at the transient state of a linear multi-degree-of-freedom(MDOF)system to random excitations,but a closed-form solution was not available unless the excitation was assumed to be a physically unrealizable white noise process.This study derives explicit,closed-form solutions for the response covariances at the transient state by using a pole-residue(PR)approach operated in the Laplace domain when the excitations are assumed to be stationary random processes described by physically realizable spectral density functions.By using the PR method,we can analytically solve the triple integral in evaluating the nonstationary response covariance.As this approach uses the poles and residues of system transfer functions,rather than the conventional mode superposition technique,the method is applicable to MDOF systems with non-classical damping models.Particular application of the proposed method is demonstrated for multi-story shear buildings to stochastic ground acceleration characterized by the Kanai–Tajimi spectral density function model,and a numerical example is provided to illustrate the detailed steps.No numerical integrations are required for computing the response covariances as the exact closed-form solution has been derived.The correctness of the proposed method is numerically verified by Monte Carlo simulations.

EXISTENCE OF POSITIVE SOLUTION FOR A TWO-PATCHES COMPETITION SYSTEM WITH DIFFUSION AND TIME DELAY AND FUNCTIONAL RESPONSE

By using the continuation theorem of coincidence theory, the existence of a positive periodic solution for a two patches competition system with diffusion and time delay and functional responsex [FK(W1*3/4。*2/3]′ 1 (t)=x 1(t)a 1(t)-b 1(t)x 1(t)-c 1(t)y(t)1+m(t)x 1(t)+D 1(t)[x 2(t)-x 1(t)], x [FK(W1*3/4。*2/3]′ 2 (t)=x 2(t)a 2(t)-b 2(t)x 2(t)-c 2(t)∫ 0 -τ k(s)x 2(t+s) d s+D 2(t)[x 1(t)-x 2(t)], y′(t)=y(t)a 3(t)-b 3(t)y(t)-c 3(t)x 1(t)1+m(t)x 1(t)is established, where a i(t),b i(t),c i(t)(i=1,2,3),m(t) and D i(t)(i=1,2) are all positive periodic continuous functions with period w >0, τ is a nonnegative constant and k(s) is a continuous nonnegative function on [- τ ,0].