Increase Of Service Time Research Articles

An event‐driven fusion framework with auto‐scaling of edge intelligence for resilient smart applications in developing countries

AbstractInternet of Things has been a popular technology in recent years for deploying a large‐scale, smart environment monitoring application across the country, using fog computing and the cloud. However, most locations of the developing countries suffer from power outages and limited network connectivity. Moreover, varied population in different locations, may lead to either frequent or rare changes in the state of the monitored environment. Due to these stochastic conditions, there may be substantial increase in service time of the application with unnecessary battery and resource consumption of the fog node. For efficient utilization of fog node resources in dynamic environment conditions, an event‐driven information fusion framework is proposed using docker containerization technology and MQTT (Message Queuing Telemetry Transport) as application layer protocol. The proposed framework provides resilience to the application in the presence of stochastic conditions and auto‐scales edge intelligence with minimum scaling operations. The performance of the framework is validated on a smart sanitation system use‐case application, proposed for autonomous monitoring of restrooms deployed in Indian rural and semi‐urban environment, and the experimental result show deviation of 2.8% in average response time of the application with average accuracy of 98.9%.

Dialysis Center Business Plan: Design Thinking Marketing Strategy In Haemodialysis Services


 
 
 
 
 
 
 
 
 
 
 
 
 Chronic kidney disease (CKD) is an important public and medical problem in the world because of the huge burden on the health care system. The prevalence of CKD has increased dramatically in the last three decades The study was conducted at the RS X Dialysis Unit in February-March 2023. This research is a descriptive-analytical research. The type of data used is primary data and secondary data. The primary data used are the results of interviews. Identify internal factors based on indicators of strengths and weaknesses. The identification process aims to assess and evaluate the internal strategic factors that influence the success of hemodialysis services. Internal factors used in research based on the state of the Dialysis Unit in terms of management, marketing, research and development and information systems. The position of hemodialysis services at the Dialysis Unit of RS X Depok City is in a growth position. From the results of data processing using QSPM, alternative strategies are obtained, namely maintaining good service quality and facilities, increasing service time in accordance with the target achievement per day which is aligned with the availability of human resources, opening services for infectious spaces open for outpatients, utilizing Social Media for access socialization when the main access is closed during holidays, social media intervention in the marketing process related to the convenience of doing HD in RS X Depok City and education related to PGK-HD, make the HD RS X Depok City patient community a forum for sharing and educating patients and increasing the ease of access and HD facilities at RS X Depok City.
 
 
 
 
 
 
 
 
 
 
 
 

Application and Practice of Variable Axial Force Cable in Powerhouse Truss Reinforcement System

Long-span steel structure trusses are widely used in factory buildings. However, with the increase in service time and dynamic load fatigue, transverse cracks at the bottom of the middle span and oblique deformation of the abdomen during the operation process may appear in a considerable part of long-span trusses with dynamic load. The U-shaped cracks at the bottom and belly, as well as the mid-span down deflection of the main truss, can also reduce the functionality of the factory building truss structure and limit the original crane load, thus affecting the normal safety and durability of the structure. Therefore, the principle of variable axial force cable system in the long-span factory building truss structure and 3D3S software modelling were applied. Analysing and studying the reinforcement method of large-span powerhouse trusses can provide practical experience for subsequent similar projects. In view of the above phenomenon, the large-span powerhouse trusses of Hongcheng Powerhouse No. 1 and No. 2, located in Tonglu, Zhejiang Province, were used as the research objects, and the variable axial force cable method was proposed to strengthen and lift the load. Considering the span of the powerhouse truss, a cable system with 22 m and a controlling force of 400 kN was proposed for Powerhouse 1, and a cable system with a variable axial force of 24 m was proposed for Powerhouse 2. The force model of large-span trusses was established by using the finite element method, which is commonly used to analyse the force of the truss. The influence of the reinforcement effect was analysed under two working conditions and compared from three aspects: stiffness, bearing capacity and stability. Furthermore, the phenomenon of uneven stress distribution was analysed. The stress distribution characteristics of each node were understood by simulating the most disadvantageous node plates with the greatest internal force before and after reinforcement.

Microstructure and mechanical degradation of K403 Ni-based superalloy from ultra-long-term serviced turbine blade

The effective characterization of the mechanical property degradation of turbine blades in service for an ultra-long-term had a significant impact on the service safety and maintenance decisions of turbine blades. In this study, the microstructure observation and mechanical property study of the K403 polycrystalline Ni-based superalloy turbine blade under four service times were carried out, using microstructure characterization methods to quantify the microstructure evolution of the superalloy at different parts of the turbine blade with increasing service time. The effects of the microstructure degradation of the superalloy under ultra-long-term service on the mechanical properties of the turbine blade were analyzed. The results show that the microstructural degradation characteristics of the superalloy turbine blades under ultra-long-term service were strongly correlated with the spatial structural characteristics of the turbine blades after service, and it was found that the carbon elements and other elements inside and at the boundary of the carbide showed regular migration behavior with the increase in service time. The regular influence of microstructural degradation of superalloy turbine blades under ultra-long-term service on their mechanical properties was demonstrated. These results can provide empirical support for the study of the predicted residual properties of nickel-based superalloy turbine blades under ultra-long-term service.

Time-Varying Evolution Behaviors of Steel–Concrete Composite Girders with Differentiated Connectors

To improve the cracking resistance of a concrete slab in the hogging moment region, a new concept called uplift-restricted and slip-permitted (URSP) connection technology has been proposed. Several studies have been conducted on URSP connectors, but investigations into the time-varying evolution behaviors of composite beams with URSP connectors are still lacking. In this paper, three types of elaborate finite element models of composite girders with differentiated connectors and different construction methods were established. Simulation of the concrete shrinkage and creep effect was realized using a user subroutine based on an improved rate-type formulation. The performances of the composite girders in three schemes were analyzed and compared in both the construction and service stages. The results demonstrated that the URSP connection technique can effectively increase the prestressing efficiency and decrease the tensile stress of the concrete induced by dead loads and vehicle loads. With an increasing service time, the concrete shrinkage effect will enhance the advantage of the URSP connection technique, and the creep effect will reduce this advantage. Finally, parametric analyses were conducted, and a value of 0.2 is recommended for the URSP length ratio to promote practical applications.

Detection system of near Earth objects based on the axial orbit in the Sun–Earth circular restricted three-body problem

L4 and L5 axial orbits provide special locations to monitor and search for near Earth objects (NEOs) due to their offset locations. In this paper, we propose a detection system of NEOs on the axial orbit in the Sun–Earth circular restricted three-body problem. Taking the Sun exclusion zone into consideration, we design an observation strategy for space-based telescopes on axial orbits. Then, an observation accessibility measure for the motionless point is presented to evaluate the performances of the different axial orbits and formations. In addition, the detection performance of axial orbits is compared with the distant retrograde orbits (DROs) and Earth-displaced heliocentric orbits (EDHOs). Numerical simulations indicate that the detection performance of axial orbits for the motionless point is better than that of DROs but is inferior to EDHOs. On the other hand, the axial orbit is dynamical stable, but EDHOs are unstable and their fuel costs for maintenance cannot be ignored with the increase of service time. Furthermore, the detection system on axial orbits is applied to moving objects. For example, the detection system of the EDHOs cannot predict the Chelyabinsk asteroid impact, but it is possible for the DRO and axial orbits. Numerical simulations for 4000 virtual NEOs indicate that due to a better observation geometry, the detection system of axial orbits can find more NEOs than those of the DRO and EDHOs.

Exploring Exact Effects of Various Factors on Chloride Diffusion in Cracked Concrete: ABAQUS-Based Mesoscale Simulations

Chloride ion attack is a major cause of concrete durability problems, and existing studies have rarely addressed the effects of damage zones. In this paper, an improved mesoscale model including five phases was constructed using the finite element software ABAQUS to study the diffusivity of chloride ions in cracked concrete. It was found that the damage zone is negligible when the crack width is less than 50 μm, while the width and depth of the damage zone are about 15 times the crack width and 15% of the crack depth when the crack is greater than 50 μm. The results show that the diffusion of chloride is greatly influenced by the crack width, while it is little-influenced by the crack shape. Low water-cement ratio and adequate hydration of the concrete are also key factors affecting chloride diffusion. In contrast, regular rounded aggregates have a positive effect on reducing chloride diffusion compared to irregularly shaped aggregates, and this effect becomes weaker with increasing service time. In addition, the protective layer can effectively prevent the diffusion of chloride in concrete. Therefore, when designing marine concrete, efforts should be made to ensure that the concrete has a low water-cement ratio, adequate hydration, less cracking and a protective layer.

Application of Fuzzy Adaptive Control in Gun Servo System

Friction torque is an important parameter affecting the servo system, which will decrease with the increase of service time. With the change of friction torque, the control characteristics of the servo system will change, resulting in the servo dynamic and static performance can not meet the system requirements. On the basis of expounding the composition and working principle of gun pitching servo system, a control method of gun servo system based on fuzzy adaptive control is proposed. The problem of system performance change caused by the change of servo system parameters is solved. Through MATLAB simulation, it shows that the method can eliminate the influence of friction torque change on the system, make the system insensitive to the change of torque parameters, and meet the use requirements under various parameter conditions.

Rotate Vector Reducer Fault Diagnosis Model Based on EEMD-MPA-KELM

With the increase of service time, the rotation period of rotating machinery may become irregular, and the Ensemble Empirical Mode Decomposition (EEMD)can effectively reflect its periodic state. In order to accurately evaluate the working state of the Rotate Vector (RV) reducer, the torque transfer formula of the RV reducer is first derived to theoretically prove periodicity of torque transfer in normal operation. Then, EEMD is able to effectively reflect the characteristics of data periodicity. A fault diagnosis model based on EEMD-MPA-KELM was proposed, and a bearing experimental dataset from Xi‘an Jiaotong University was used to verify the performance of the model. In view of the characteristics of the industrial robot RV reducer fault was not obvious and the sample data is few, spectrum diagram was used to diagnose the fault from the RV reducer measured data. The EEMD decomposition was performed on the data measured by the RV reducer test platform to obtain several Intrinsic Mode Functions (IMF). After the overall average checking and optimization of each IMF, several groups of eigenvalues were obtained. The eigenvalues were input into the Kernel Extreme Learning Machine (KELM) optimized by the Marine Predators Algorithm (MPA), and the fault diagnosis model was established. Finally, compared with other models, the prediction results showed that the proposed model can judge the working state of RV reducer more effectively.

Degradation of microstructure and strength properties of heat-resistant steels operating under variable loads

The paper presents the results of the structure and mechanical tests of the low-alloy steel 14MoV6-3 which shows internal damage after long-term creep service. The tests of mechanical properties, including: tensile and yield strength at room temperature, yield strength at elevated temperature (+540 °C) and brittle transition temperature, were carried out on longitudinal samples in accordance with the requirements of standards for elements pressure equipment. The internal damage of the tested material was also classified depending on the degree of wear, based on the principles set out in the industry specification. It was shown that the strength properties of the tested material from pipelines operated under primary steam conditions decrease with increasing service time. Microscopic tests (Scanning Electron Microscope SEM) revealed that the cause of damage to steel with a ferrite-bainite structure after long-term operation is the cavitation cracking mechanism. The study of the microstructure was also carried out by means of the backscattered electron diffraction method EBSD using the IQ, KAM and GOS functions. These parameters are very important in terms of analysis of the occurring structural changes in the fatigue and creep processes. They allow to determine the deformed part of the substructure subjected to these processes.

Horizontal Bearing Capacity and Reliability of Piles in Coastal Soft Soil Considering the Time-Varying Characteristics

In order to study the influence of the creep of soft soil and the corrosion damage of reinforced concrete on the horizontal bearing behavior of piles, the novel p-y curve model was established considering the time-varying characteristics of soil parameters. The attenuation law of the bending stiffness of reinforced concrete piles under chloride erosion was analyzed by introducing the bending stiffness reduction factor. The limit state function of pile reliability analysis was then established considering the time-varying characteristics. The reliability index of a pile under horizontal displacement failure mode was obtained using the quadratic response surface method. Finally, the sensitivity analysis of random variables (cohesion, internal friction angle, concrete cover, and chloride concentration) on the time-varying reliability of a pile under horizontal displacement failure mode was carried out. The influence of the distribution types of soil parameters on the time-varying reliability was considered. The results show that the load-bearing characteristics of the horizontally loaded pile are impacted significantly by the time-varying characteristics of the soil. The maximum horizontal displacement of the pile increases nonlinearly with the increase in service time. When the horizontal displacement failure mode occurs, the variability in the internal friction angle has a significant impact on the reliability of the pile. The reliability index decreases nonlinearly with an increase in service time. When the soil parameters obey the extreme value type I distribution, the corresponding reliability index is greater than that of log-normal distribution and normal distribution.

Feature Fusion-Based Inconsistency Evaluation for Battery Pack: Improved Gaussian Mixture Model

The large-scale grouping of the battery system leads to the inconsistency of the battery pack. Aiming at tacking this issue, an inconsistency evaluation method is deployed for the battery pack based on an improved Gaussian mixture model (GMM) and feature fusion approach. Specifically, the proposed adaptive forgetting factor recursive least squares (AFFRLS) algorithm allows the open-circuit voltage and other parameters to be jointly identified without the open circuit voltage-state of charge (OCV-SOC) test. An online capacity estimation approach with the extended Kalman particle filter (EPF) is put forward for capacity estimation. Further, an improved GMM is proposed to visualize battery pack inconsistency, using the K-means++ algorithm to initialize category centers. The standard deviation coefficient approach quantifies the inconsistency. Finally, the real-life vehicle data are performed to validate the effectiveness of the proposed method. The experimental results show that the proposed method can evaluate the battery parameters accurately. With the increase in service time, the inconsistency of the battery pack is gradually deteriorating.

Surface residual stress detection method for aero-engine blades based on active thermal deformation excitation

ABSTRACT Surface residual stress is made on the aero-engine blades by shot peening to improve the fatigue life of the blades. As the service time increases, the surface residual stress is decreasing due to thermomechanical relaxation and the centrifugal load caused by high-speed rotation. Therefore, the surface residual stress detection is of great importance for predicting the remaining life of aero-engine blades. Up to now, efficient and non-contact detection of surface residual stress is still a challenge. In this paper, an active thermal deformation excitation (ATDE) method for surface residual stress is proposed. According to the thermal deformation theory, the thermal deformation of the material is positively correlated with the surface residual stress, and by measuring the thermal deformation the surface residual stress can be detected and evaluated. The theoretical deformation model was established, and simulation models with different surface residual stresses were constructed. A detection system was proposed to detect the blade deformation with different surface residual stresses. Results show that there was a linear relationship between the blade deformation and the surface residual stress from −636 Mpa to −1403 Mpa.

Evaluation of the field-aged performance of foamed warm mix asphalt: Comparisons with hot mix asphalt

The foamed warm mix asphalt (FWMA) has been widely used as a sustainable construction technique in pavement engineering, yet has not yet been fully studied for its aging performance or durability. Here we aim to examine and evaluate the performance variation characteristic of FWMA compared with conventional hot mix asphalt (HMA) under long-term service conditions. The performance evolution of FWMA core samples drilled from four highways was compared to that of ordinary HMA, which was simultaneously constructed. Fourier transform infrared (FTIR), dynamic shear rheology (DSR), and bending beam rheometer (BBR) tests were respectively performed to evaluate the aging degree, high-temperature, and low-temperature rheological characteristics. The results demonstrated that the aging resistance of foamed WMA was slightly diminished under construction conditions with no temperature reduction. With increased service time, the rheological characteristics of FWMA were enhanced at high temperatures, while deteriorated at low temperatures. The foaming water and service time were primary determinants of the aging as well as high and low-temperature rheological properties of FWMA without temperature construction reduction. Additionally, the aging degree of FWMA under short-term and long-term service was smaller than HMA when the construction temperature decreased. The rheological characteristics of FWMA were inferior to those of HMA during both short-term and long-term service stages. Under conditions of temperature reduction, foaming water and mixing temperature exhibited a considerable influence on the aging and rheological properties of FWMA at high and low temperatures. Therefore, the amount of water used for foaming and the temperature of production should be strictly control in the foamed warm mix asphalt technology.

Collaborative optimization of last-train timetables for metro network to increase service time for passengers

Last-train timetables are significant in metro systems and directly influence transportation organization efficiency and passenger service levels. This study focuses on the collaborative optimization of last-train timetables for a large-scale metro network. Different from most studies, which often focus on improving the ability of passengers to transfer between different metro lines (transfer accessibility) during the last-train period, or the ability of passengers to reach their destinations after boarding the last train service from the origin station (origin-destination (OD) accessibility), this work aims to optimize the latest time for passengers (LTP) to reach their destinations using the metro services. A mixed-integer linear programming (MILP) model is established to optimize the last-train timetables with maximizing LTPs. For comparison, two MILP models respectively aim at maximizing transfer accessibilities and OD accessibilities, are adopted as benchmarks. An improved genetic algorithm based on Q-learning (QGA) is developed to solve the proposed MILP models for optimizing last-train timetables for a large-scale metro network. The proposed method is validated by optimizing the last-train timetable of the metro network of Chengdu, China. The results indicate that compared with optimizing the transfer and OD accessibilities, optimizing LTPs can consider both single-line and multiple-line passenger benefits, and directly increase their accessibilities and feasible times to use the metro service.

Time-dependency deterioration of polypropylene fiber reinforced soil and guar gum mixed soil in loess cut-slope protecting

Ecological materials are increasingly being applied in the loess slope protection, and the time-dependency deterioration of materials is an important criterion in evaluating their protective effects. Taking polypropylene fiber and guar gum as examples, the protection tests of these two ecological materials were carried out for a typical bare cut-slope on the Loess Plateau in this study. We quantified the erosion deterioration based on the approach of LiDAR, and the deterioration processes of both the ecological materials were then comprehensively evaluated. Results showed that both the materials could generate good protective effects on the test slopes, and the guar gum mixed soil (GGS) was slightly better than polypropylene fiber reinforced soil (PFS) at initial time. However, the two materials deteriorated diversely with the increasing service time. The scouring erosion was mainly observed in PFS, which is different from the surface spalling observed in GGS. The erosion mass of the two slopes also presented different stepwise growth along the slope downward. In addition, the protective advantage of GGS was decreasing and even disappearing over time. Revealed by the dry-wet cycle tests in laboratory, the rapid attenuation of disintegration resistance of PFS and shear strength parameters of GGS were the main reasons leading to the different deterioration of the two materials. The time-dependency deterioration model was furthermore established by combining the average intensity of effective rainfall as well as the disintegration rate and shear strength parameters of slope protection materials. The model indicated that the influences of disintegration rate, cohesion, and internal friction angle enhanced successively on the protective effects of slope protection materials. This study is of great significance for revealing the deterioration mechanism and promoting continuous improvement of slope protection materials.

Identifying airline passengers satisfaction and ground airport services perception of kolkata airport during COVID19- ASQ (Airport Service Quality) perspective

Background: The research on the airlines' ground services in airports is central to the business environment, impacting the departure and arrival functions, while COVID-19 has adversely affected service capabilities, impacting passenger safety and satisfaction. Aims: The aim is to find the factors influencing airport services during COVID-19 from the passenger perspective using the Airport Service Quality (ASQ) framework.Methods- ASQ (Airport service quality) scale was used with 39 items for a sample of 200, tested in SPSS for reliability and validity, and underwent factor analysis. Results-Airport management of Kolkata has emphasize the role of leadership management to focus on the airport ground services, with a new set of service protocols by WHO adapted to Kolkata ground services. Moderately satisfactory COVID-19 arrangements with, hand washing provision, facilities for immediate quarantine facility, disposal procedure, and way finding within Kolkata airport also have passengers who do not exhibit social conformance behaviour towards social distancing. Conclusion- Airport leadership management in airport ground services has accommodated the new COVID19 service that needs to match passenger behaviour aberrations to eliminate issues of contamination. Visual signage and way-finding guide passengers' well-being and satisfaction, while passengers must in the face of increased service time when following COVID19 service protocols.

Microstructural evolution in S31042 heat-resistant steel after service and the effect on hardness

The ultra-supercritical power generation technology with high energy efficiency and low emissions is one of the important ways to solve the current increasingly prominent energy problems in the context of international development requirements for carbon neutrality and the increasingly prominent energy shortage. Because of its excellent resistance to high temperature corrosion and organizational stability, S31042 is commonly employed in the most severe working environment of ultra-supercritical units. Due to its great resistance to high-temperature corrosion and organizational stability, S31042 is commonly employed in the most demanding components of ultra-supercritical units such as high-temperature reheaters and high-temperature superheaters. Various characterisation approaches were employed in this research to reflect the microstructure of S31042 heat-resistant steel in service under various time length conditions, and the hardness of S31042 heat-resistant steel was assessed under the corresponding service conditions. The results showed that the hardness of S31042 increased significantly with increasing service time, from around 160 Hv at the time of non-service to nearly 220 Hv after 75360 hours of service. The continuous distribution of uniformly sized M23C6 phase on the grain boundaries of S31042 developed toward grain coarsening after service, but the precipitation strengthening effect produced by the nanoscale secondary NbCrN phase appearing in the grains was the main reason for the increase of the hardness value of S31042, according to the microstructure of the material.

Time-Dependent Seismic Performance of Coastal Bridges Reinforced with Hybrid FRP and Steel Bars.

To increase the durability and seismic resilience of coastal bridges, a hybrid reinforced concrete (HRC) bridge that incorporates both glass fiber-reinforced polymer (GFRP) bars and steel bars is proposed. The time-dependent seismic performance of the HRC bridge is comprehensively investigated at three levels, namely the material, bridge column and bridge structure levels. First, the decrease of tensile strength of GFRP bars over time is analyzed based on the Arrhenius theory, and corrosion initiation time and performance deterioration of steel bars are determined by Fick’s second law and an empirical formula. Second, an efficient finite element modeling method for aging HRC bridge columns is proposed. Simulation of the compression/tension behavior and the fracture failure of the GFRP bar is described. Hysteretic analysis is further conducted to investigate the time-dependent energy dissipation, ductility, residual displacement, bearing capacity and post-yield stiffness ratio. Meanwhile, comparisons of HRC bridge columns to reinforced concrete (RC) references are provided. Third, the seismic demand and damage evolution of deteriorated HRC bridge structures are investigated through dynamic time-history analysis. The results indicate that the corrosion-resistant GFRP bars contribute to improving the bearing capacity and to reducing the residual displacement of the HRC bridge. With an increase in service time, the seismic damage to the bridge column, abutment and expansion bearing increases, but the damage to fixed bearing decreases. Research results presented herein show that the HRC bridge is a promising alternative structure scheme in the marine environment.

Asymptotic Analysis of Resource Heterogeneous QS $$ (\mathrm {MMPP}+2\mathrm {M})^{(2,\nu )}/\mathrm {GI}(2)/\infty $$ under Equivalently Increasing Service Time

Asymptotic Analysis of Resource Heterogeneous QS $$ (\mathrm {MMPP}+2\mathrm {M})^{(2,\nu )}/\mathrm {GI}(2)/\infty $$ under Equivalently Increasing Service Time