Multi-Time Scale Operation and Simulation Strategy of the Park Based on Model Predictive Control

Due to the impact of source-load prediction power errors and uncertainties,the actual operation of the park will have a wide range of fluctuations compared with the expected state,resulting in its inability to achieve the expected economy.This paper constructs an operating simulation model of the park power grid operation considering demand response and proposes a multi-time scale operating simulation method that combines day-ahead optimization and model predictive control(MPC).In the day-ahead stage,an operating simulation plan that comprehensively considers the user’s side comfort and operating costs is proposed with a long-term time scale of 15 min.In order to cope with power fluctuations of photovoltaic,wind turbine and conventional load,MPC is used to track and roll correct the day-ahead operating simulation plan in the intra-day stage to meet the actual operating operation status of the park.Finally,the validity and economy of the operating simulation strategy are verified through the analysis of arithmetic examples.

Associate factors for endoscopic submucosal dissection operation time and postoperative delayed hemorrhage of early gastric cancer

BACKGROUND Endoscopic submucosal dissection(ESD)is a treatment for early gastric cancer with the advantages of small invasion,fewer complications,and a low local recurrence rate.However,there is a high risk of complications such as bleeding and perforation,and the operation time is also longer.ESD operation time is closely related to bleeding and perforation.AIM To investigate the influencing factors associated with ESD operation time and postoperative delayed hemorrhage to provide a reference for early planning,early identification,and prevention of complications.METHODS We conducted a retrospective study based on the clinical data of 520 patients with early gastric cancer in the Second Affiliated Hospital of Hainan Medical University from January 2019 to December 2021.The baseline data,clinical features,and endoscopic and pathological characteristics of patients were collected.The multivariate linear regression model was used to investigate the influencing factors of ESD operation time.Logistic regression analysis was carried out to evaluate the influencing factors of postoperative delayed hemorrhage.RESULTS The multivariate analysis of ESD operation time showed that the maximum lesion diameter could affect 8.815%of ESD operation time when other influencing factors remained unchanged.The operation time increased by 3.766%or 10.247%if the lesion was mixed or concave.The operation time increased by 4.417%if combined with an ulcer or scar.The operation time increased by 3.692%if combined with perforation.If infiltrated into the submucosa,it increased by 2.536%.Multivariate analysis of delayed hemorrhage after ESD showed that the maximum diameter of the lesion,lesion morphology,and ESD operation time were independent influencing factors for delayed hemorrhage after ESD.Patients with lesion≥3.0 cm(OR=3.785,95%CI:1.165-4.277),lesion morphology-concave(OR=10.985,95%CI:2.133-35.381),and ESD operation time≥60 min(OR=2.958,95%CI:1.117-3.526)were prone to delayed hemorrhage after ESD.CONCLUSION If the maximum diameter of the lesion in patients with early gastric cancer is≥3.0 cm,and the shape of the lesion is concave,or accompanied by an ulcer or scar,combined with perforation,and infiltrates into the submucosa,the ESD operation will take a longer time.When the maximum diameter of the lesion is≥3.0 cm,the shape of the lesion is concave in patients and the operation time of ESD takes longer time,the risk of delayed hemorrhage after ESD is higher.

Effect of self-made exhaust plaster on patients with gastrointestinal dysfunction after gynecological operation

Objective:To explore the effect of self-made exhaust patch(SMEP)on gastrointestinal dysfunction after gynecological operation.Methods:A total of 200 patients with gynecological operation in the gynecological ward of Shandong Changle People's Hospital were randomly divided into the control group(n=100)and the treatment group(n=100).The recovery time of bowel sounds,the time of first anal exhaust,the duration of abdominal distention,the duration of abdominal pain,the incidence of abdominal distention and abdominal pain and linical efficacy of SMEP were observed.Results:Compared with the control group,the recovery time of gastrointestinal function and the first anal exhaust time in the treatment group were shorter;the duration of abdominal distention and abdominal pain in the treatment group were shorter than those in the control group(P<0.05);Cure rate of abdominal distention in the treatment is 62.5%and cure rate of abdominal pain in the treatment is 60%within 72 hours after operation,which is higher than that in the control group(44.%,45.9%).Conclusion:The results showed that the self-made exhaust patch can improve the clinical symptoms of patients after gynecological abdominal surgery,and the self-made exhaust patch had a significant effect on gastrointestinal dysfunction after gynecological surgery,which was worthy of clinical promotion.

Timing of surgical operation for patients with intra-abdominal infection:A systematic review and meta-analysis

BACKGROUND Intra-abdominal infections(IAIs)is the most common type of surgical infection,with high associated morbidity and mortality rates.In recent years,due to the use of antibiotics,various drug-resistant bacteria have emerged,making the treatment of abdominal infections more challenging.Early surgical exploration can reduce the mortality of patients with abdominal infection and the occurrence of complications.However,available evidence regarding the optimal timing of IAI surgery is still weak.In study,we compared the effects of operation time on patients with abdominal cavity infection and tried to confirm the best timing of surgery.AIM To assess the efficacy of early vs delayed surgical exploration in the treatment of IAI,in terms of overall mortality.METHODS A systematic literature search was performed using PubMed,EMBASE,Cochrane Central Register of Controlled Trials,Ovid,and ScienceDirect.The systematic review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-analyses method.Based on the timing of the surgical operation,we divided the literature into two groups:Early surgery and delayed surgery.For the early and delayed surgery groups,the intervention was performed with and after 12 h of the initial surgical intervention,respectively.The main outcome measure was the mortality rate.The literature search was performed from May 5 to 20,2021.We also searched the World Health Organization International Clinical Trials Registry Platform search portal and ClinicalTrials.gov on May 20,2021,for ongoing trials.This study was registered with the International Prospective Register of Systematic Reviews.RESULTS We identified nine eligible trial comparisons.Early surgical exploration of patients with IAIs(performed within 12 h)has significantly reduced the mortality and complications of patients,improved the survival rate,and shortened the hospital stay.CONCLUSION Early surgical exploration within 12 h may be more effective for the treatment of IAIs relative to a delayed operation.

Combined hybrid energy storage system and transmission grid model for peak shaving based on time series operation simulation

This study proposes a combined hybrid energy storage system(HESS) and transmission grid(TG) model, and a corresponding time series operation simulation(TSOS) model is established to relieve the peak-shaving pressure of power systems under the integration of renewable energy. First, a linear model for the optimal operation of the HESS is established, which considers the different power-efficiency characteristics of the pumped storage system, electrochemical storage system, and a new type of liquid compressed air energy storage. Second, a TSOS simulation model for peak shaving is built to maximize the power entering the grid from the wind farms and HESS. Based on the proposed model, this study considers the transmission capacity of a TG. By adding the power-flow constraints of the TG, a TSOS-based HESS and TG combination model for peak shaving is established. Finally, the improved IEEE-39 and IEEE-118 bus systems were considered as examples to verify the effectiveness and feasibility of the proposed model.

Dynamic train dwell time forecasting:a hybrid approach to address the influence of passenger flow fluctuations

Train timetables and operations are defined by the train running time in sections,dwell time at stations,and headways between trains.Accurate estimation of these factors is essential to decision-making for train delay reduction,train dispatching,and station capacity estimation.In the present study,we aim to propose a train dwell time model based on an averaging mechanism and dynamic updating to address the challenges in the train dwell time prediction problem(e.g.,dynamics over time,heavy-tailed distribution of data,and spatiotemporal relationships of factors)for real-time train dispatching.The averaging mechanism in the present study is based on multiple state-of-the-art base predictors,enabling the proposed model to integrate the advantages of the base predictors in addressing the challenges in terms of data attributes and data distributions.Then,considering the influence of passenger flow on train dwell time,we use a dynamic updating method based on exponential smoothing to improve the performance of the proposed method by considering the real-time passenger amount fluctuations(e.g.,passenger soars in peak hours or passenger plunges during regular periods).We conduct experiments with the train operation data and passenger flow data from the Chinese high-speed railway line.The results show that due to the advantages over the base predictors,the averaging mechanism can more accurately predict the dwell time at stations than its counterparts for different prediction horizons regarding predictive errors and variances.Further,the experimental results show that dynamic smoothing can significantly improve the accuracy of the proposed model during passenger amount changes,i.e.,15.4%and 15.5%corresponding to the mean absolute error and root mean square error,respectively.Based on the proposed predictor,a feature importance analysis shows that the planned dwell time and arrival delay are the two most important factors to dwell time.However,planned time has positive influences,whereas arrival delay has negative influences.

Design and operation strategies of the system for destroying time-sensitive target based on system effectiveness

To improve the effect of destroying time-sensitive target （TST）, a method of operational effectiveness evaluation is presented and some influential factors are analyzed based on the combat flow of system for destroying TST. Considering the possible operation modes of the system, a waved operation mode and a continuous operation mode are put forward at first. At the same time, some relative formulas are modified. In examples, the influential factors and operation modes are analyzed based on the system effectiveness. From simulation results, some design and operation strategies of the system for destroying time sensitive targets are concluded, which benefit to the improvement of the system effectiveness.

Clinical efficacy and safety of kyphoplasty for the treatment of osteoporotic vertebral compression fractures at different surgical timings based on the theory of“dynamic-static integration”

Objective:To investigate the clinical efficacy and safety of percutaneous kyphoplasty at different surgical timings in the treatment of osteoporotic vertebral compression fracture(OVCF)based on the theory of“dynamic-static integration”.Methods:Patients with OVCF who underwent percutaneous kyphoplasty in our hospital were selected and divided into Groups A,B,and C for those undergoing surgery within 7,7—21,and>21 days of fracture occurrence.The variations in the amount of bone cement injected,pre-and post-operative pain levels,functional activity,deformity correction of the injured vertebrae,bone cement leakage,and vertebral body height loss were compared among the three groups.Results:Regarding pain relief and functional activity,the postoperative Visual Analog Scale and Oswestry Disability Index scores of the three groups significantly improved.Furthermore,the deformities of the injured vertebrae in the three groups were significantly corrected,with Groups A and B exhibiting superior correction compared to Group C.Moreover,the bone cement leakage rates in groups A and C were higher than that in Group B.At the 3-month follow-up,the loss of vertebral height in Group C was significantly higher than those in groups A and B.Conclusion:Kyphoplasty is effective for OVCF treatment.Early surgery can effectively restore the vertebral height of the injured vertebra,reduce kyphosis,and reduce height loss of the injured vertebra after surgery;nevertheless,treatment within 1—3 weeks of the fracture can reduce the occurrence of bone cement leakage,making the surgery safer.Therefore,surgical treatment within 1—3 weeks of fracture is safer and can achieve satisfactory therapeutic effects.From the perspective of traditional Chinese medicine,PKP surgery can transform the fracture end from a micromotion state to a fixed state,which fully embodies the theory of“dynamic-static integration”.

Accelerated Primal-Dual Projection Neurodynamic Approach With Time Scaling for Linear and Set Constrained Convex Optimization Problems

The Nesterov accelerated dynamical approach serves as an essential tool for addressing convex optimization problems with accelerated convergence rates.Most previous studies in this field have primarily concentrated on unconstrained smooth con-vex optimization problems.In this paper,on the basis of primal-dual dynamical approach,Nesterov accelerated dynamical approach,projection operator and directional gradient,we present two accelerated primal-dual projection neurodynamic approaches with time scaling to address convex optimization problems with smooth and nonsmooth objective functions subject to linear and set constraints,which consist of a second-order ODE(ordinary differential equation)or differential conclusion system for the primal variables and a first-order ODE for the dual vari-ables.By satisfying specific conditions for time scaling,we demonstrate that the proposed approaches have a faster conver-gence rate.This only requires assuming convexity of the objective function.We validate the effectiveness of our proposed two accel-erated primal-dual projection neurodynamic approaches through numerical experiments.

Estimation of Standard Operation Time of Flight Legs Based on Clustering and Probability Analysis

A clustering algorithm and a probability statistics method were applied to different phases of a flight to analyze operation time during aircraft ground taxiing and airborne flight.And the clustering pattern,distribution characteristics and dynamically changing rules of the two phases were identified.Further,an estimate method was established to measure operation time of flight legs,with creative steps of calculating individual segment separately and then integrating them accordingly.The method can both objectively and dynamically measure operation time,and accurately reflect real situation.It helps to better utilize airport slot resources and provides a strong support for air traffic flow management when scheduling flight plan in strategic and pre-tactic phases.

Improving entanglement of assistance by local parity–time symmetric operation

We investigate entanglement of assistance without and with decoherence using a local non-Hermitian operation, i.e.,parity–time(PT) symmetric operation. First we give the explicit expressions of entanglement of assistance for a general W-like state of a three-qubit system under a local parity–time symmetric operation. Then for a famous W state without decoherence, we find that entanglement of assistance shared by two parties can be obviously enhanced with the assistance of the third party by a local parity–time symmetric operation. For the decoherence case, we provide two schemes to show the effects of local parity–time symmetric operation on improvement of entanglement of assistance against amplitude damping noise. We find that for the larger amplitude damping case the scheme of PT symmetric operation performed on one of two parties with the influence of noise is superior to that of PT symmetric operation performed on the third party without the influence of noise in suppressing amplitude damping noise. However, for the smaller amplitude damping case the opposite result is given. The obtained results imply that the local PT symmetric operation method may have potential applications in quantum decoherence control.

The effect of weeding frequency and schedule on weeding operation time: a simulation study on a sugi (Cryptomeria japonica) plantation in Japan

This study quantified the effect of weeding frequency and weeding schedules on weeding operation time in a sugi(Cryptomeria japonica)plantation stand.A weeding operation time estimation model was developed;then the cumulative weeding operation time after six growing seasons was simulated using the developed model.The developed model included weed height,relative height of weeds to sugi,and initial planting density.The simulated cumulative weeding operation time decreased approximately 6%for each one-treatment decrease in weeding frequency.Under a three-treatment weeding frequency scenario,the simulated cumulative operation time when weeding was conducted during non-consecutive years was longer than that when weeding was conducted during three consecutive years.The results suggest that carrying out weeding treatment during consecutive years is the more effective for reduction of weeding costs.We conclude that weeding schedule as well as weeding frequency must be considered for reduction of weeding operation time.

Effect of body mass index on the operation time and postoperative hospital stay of retroperitoneal laparoscopic renal cyst decortication

Objective:To investigate the effect of body mass index(BMI)on the operation time and postoperative hospital stay for patients who underwent retroperitoneal laparoscopic decortication for a single simple renal cyst.Methods:A retrospective cohort study was conducted among 81 patients with single simple renal cyst who had undergone retroperitoneal laparoscopic cyst decortication from January 2017 to December 2019 in Wuxi Xishan People's Hospital.All patients were divided into three groups according to BMI:normal group(BMI<25 kg/m^(2),n=44),overweight group(BMI=25-30 kg/m^(2),n=21),and obese group(BMI>30 kg/m^(2),n=16).Multiple linear regression was conducted to investigate the correlation.Results:The three groups were comparable in terms of age,gender,maximum diameter of cyst,and cyst location.In the aspect of operation time,only the patients in obese group had longer duration when compared with those in the normal group(59.1±15.7 min vs.45.2±12.8 min,p=0.001).And the patients in the obese group had significantly longer hospital stay compared with those in the normal group(6.2±1.9 d vs.5.2±0.5 d,p=0.002)and overweight group(6.2±1.9 d vs.5.0±1.0d,p=0.001).In the analysis of multiple linear regression,it was found that operation time is significantly affected by BMI and location 2,with coefficients of 1.299 and -8.646 respectively.The influence of BMI was greater than location 2(0.335 vs.-0.289).For hospital stay,only BMI had an effect on it,with a coefficient of 0.110.Conclusion:BMI was a major factor that associated with longer operation time and hospital stay in patients with retroperitoneal laparoscopic renal cyst decortication.

Cyberattack Ramifications, The Hidden Cost of a Security Breach

In this in-depth exploration, I delve into the complex implications and costs of cybersecurity breaches. Venturing beyond just the immediate repercussions, the research unearths both the overt and concealed long-term consequences that businesses encounter. This study integrates findings from various research, including quantitative reports, drawing upon real-world incidents faced by both small and large enterprises. This investigation emphasizes the profound intangible costs, such as trade name devaluation and potential damage to brand reputation, which can persist long after the breach. By collating insights from industry experts and a myriad of research, the study provides a comprehensive perspective on the profound, multi-dimensional impacts of cybersecurity incidents. The overarching aim is to underscore the often-underestimated scope and depth of these breaches, emphasizing the entire timeline post-incident and the urgent need for fortified preventative and reactive measures in the digital domain.

Real-Time Operation of Microgrids

Microgrid (MG) systems effectively integrate a generation mix of solar, wind, and other renewable energy resources. The intermittent nature of renewable resources and the unpredictable weather conditions contribute largely to the unreliability of microgrid real-time operation. This paper investigates the behavior of microgrid for different intermittent scenarios of photovoltaic generation in real-time. Reactive power coordination control and load shedding mechanisms are used for reliable operation and are implemented using OPAL-RT simulator integrated with Matlab. In an islanded MG, load shedding can be an effective mechanism to maintain generation-load balance. The microgrid of the German Jordanian University (GJU) is used for illustration. The results show that reactive power coordination control not only stabilizes the MG operation in real-time but also reduces power losses on transmission lines. The results also show that the power losses at some substations are reduced by a range of 6% - 9.8%.

Low-Power Operational Amplifier for Real-Time Signal Processing System of Micro Air Vehicle

A low-power complementary metal oxide semiconductor（CMOS） operational amplifier （op-amp） for real-time signal processing of micro air vehicle （MAV） is designed in this paper.Traditional folded cascode architecture with positive channel metal oxide semiconductor（PMOS） differential input transistors and sub-threshold technology are applied under the low supply voltage.Simulation results show that this amplifier has significantly low power,while maintaining almost the same gain,bandwidth and other key performances.The power required is only 0.12 mW,which is applicable to low-power and low-voltage real-time signal acquisition and processing system.

Study on the Artificial Snowfall Operation of Silver Iodide Ground Generator in Shijiazhuang City

The key of artificial precipitation(snowfall) operation with the silver iodide generator which was set on the windward slope of mountain was the selection of updraft time.The updraft related to the entering cloud efficiency of effective nucleus.By contrasting and analyzing two times artificial snowfall operations,the timing of artificial precipitation(snowfall) operation with the silver iodide ground generator was discussed.By using the synoptic chart,satellite cloud chart,radar,physical quantity calculation and so on,the operation timing was determined.

The Operation Model of Pig Supply Chain Based on Temporal and Spatial Perspectives

This paper constructed pig supply chain based on theoretical study and practical research, then analyzed the operation model of pig supply chain from tem- poral and spatial perspectives. The results showed that from the spatial perspective, pig supply chain had five models of operation, such as vertical integration pig sup- ply chain, quasi-vertical integration pig supply chain （tightly-knit pig supply chain）, semi-tightly pig supply chain, loosely-organized pig supply chain and market-oriented pig supply chain. In contrast, from temporal aspect, pig supply chain experiences the pure market transaction, contract form, cooperatives, vertical integration and hori- zontal integration model of operation; the future pig supply chain model in China might be the longitudinal transverse group alliance pig supply chain, namely, the upper vertical integration or quasi-vertical integration （leading processing enterprise ＋ farmer） and down horizontal integration （leading processing enterprises ＋ logistics company ＋ sales）, and it would be a kind of competition among interest groups by division of cooperation.

Exponential stabilization of distributed parameter switched systems under dwell time constraints

The exponential stabilization problem for finite dimensional switched systems is extended to the infinite dimensional distributed parameter systems in the Hilbert space. Based on the semigroup theory, by applying the multiple Lyapunov function method, the exponential stabilization conditions are derived. These conditions are given in the form of linear operator inequalities where the decision variables are operators in the Hilbert space; while the stabilization properties depend on the switching rule. Being applied to the two-dimensional heat switched propagation equations with the Dirichlet boundary conditions, these linear operator inequalities are transformed into standard linear matrix inequalities. Finally, two examples are given to illustrate the effectiveness of the proposed results.

Effects of hydraulic retention time, temperature, and effluent recycling on efficiency of anaerobic filter in treating rural domestic wastewater

With rural population expansion and improvement of the socio-economic standard of living, treatment of rural domestic wastewater has rapidly become a major aspect of environmental concern. Selection of a suitable method for treatment of rural domestic wastewater depends on its efficiency, simplicity, and cost-effectiveness. This study investigated the effects of hydraulic retention time （HRT）, temperature, and effluent recycling on the treatment efficiency of an anaerobic filter （AF） reactor. The first round of experimental operations was run for three months with HRTs of one, two, and three days, temperatures of 18℃, 21℃, and 24℃, and no effluent recycling. The second round of experimental operations was conducted for another three months with HRTs of three and four days; temperatures of 30.67℃, 30.57℃, and 26.91 ℃ ; and three effluent recycling ratios of 1：1, 1：2, and 2：1. The first round of operations showed removal rates of 32% to 44% for COD, 30% to 35% for TN, 32% to 36% for NH4-N, 19% to 23% for NO3-N, and 12% to 22% for TE In the second round of operations, the removal rates varied from 75% to 81% for COD, 35% to 41% for TN, 31% to 39% for NH4-N, 30% to 34% for NO3-N, and 41% to 48% for TP. The average gas production rates were 6.72 L/d and 7.26 L/d for the first and second rounds of operations, respectively. The gas production rate increased in the second round of operations as a result of applied effluent recycling. The best removal efficiency was obtained for an optimum HRT of three days, a temperature of 30℃, and an effluent recycling ratio of 2：1. The results show that the removal efficiency of the AF reactor was affected by HRT, temperature, and effluent recycling.