Optimal allocation of multi-state elements in a sliding window system with phased missions

Author(s):  
Kunxiang Yi ◽  
Gang Kou ◽  
Kaiye Gao ◽  
Hui Xiao

Many real-world engineering systems such as aerospace systems, intelligent transportation systems and high-performance computing systems are designed to complete missions in multiple phases. These types of systems are known as phased-mission systems. Inspired by an industrial heating system, this research proposes a generalized linear sliding window system with phased missions. The proposed system consists of N nodes with M multi-state elements that are subject to degradation. The linear sliding window system fails if the cumulative performance of any r consecutive nodes is less than the pre-determined demand in any phase. The degradation process of each element is modeled by a continuous-time Markov chain. A novel reliability evaluation algorithm is proposed for the linear sliding window system with phased missions by extending the universal generating function technique. Furthermore, the optimal element allocation strategy is determined using the particle swarm optimization. The effectiveness of the proposed algorithm is confirmed by a set of numerical experiments.

Author(s):  
Hui Xiao ◽  
Minhao Cao ◽  
Gang Kou ◽  
Xiaojun Yuan

Motivated by real-world complex engineering systems, this research proposes a multi-state system with two levels of performance sharing. In this system, there exists a unique performance transmitter between any two adjacent subsystems and any two adjacent elements within each subsystem. Surplus performance of a subsystem or an element can only be transmitted to its adjacent subsystems or elements. We build the reliability model of the proposed system and suggest a corresponding reliability evaluation algorithm by extending the existing universal generating function technique. Since the performance sharing is only allowed between adjacent subsystems and elements, the element allocation and sequencing will affect the system reliability. Due to the complexity of the combinatorial optimization problem, we use the genetic algorithm to find the optimal allocation and sequencing of the elements. An analytical example is provided to illustrate the reliability evaluation algorithm. Numerical experiments are carried out to demonstrate how the optimal allocation and sequencing as well as the capacities of the performance transmitters affect the system reliability.


Author(s):  
Ginger Daniels ◽  
Tim Starr

As the deployment of intelligent transportation systems (ITS) technologies moves forward, the issue of sustaining and supporting traffic management systems after they have been constructed becomes increasingly critical. In the midst of limited funding, undocumented costs, competing maintenance needs, aging systems, and institutional barriers, the systems already under operation are struggling to meet the expectations conveyed during implementation. Planning for day-to-day performance and upkeep, despite the necessity, has been an unglamourous and apparently secondary consideration in the ITS implementation process. A well-run and well-maintained system not only serves the transportation system users as intended, but boosts the credibility of the program with the public. Conversely, systems that are plagued with inadequate staffing, persistent software bugs, and inoperable field devices will fail to provide high-performance services and will certainly tarnish the ITS initiative and the credibility of all transportation service providers. Quantifying and securing the funding necessary to operate and maintain ITS and advanced traffic management systems adequately is the first step, yet very little documentation is available to assist system operators. First, a mechanism is provided for estimating the costs required to operate and maintain ITS elements adequately; second, the funding issues are examined and guidelines are provided to address the obstacles that prevent adequate funding of traffic management operations and maintenance. Although the Texas Department of Transportation costs and procedures are examined, the research and recommendations will be useful to other state agencies.


Author(s):  
Akshay Kumar ◽  
Mangey Ram

In this study, a sliding window system is revisited and evaluated interval-valued reliability in case of upper and lower form with the help of universal generating function technique and using an algorithm, how to compute the reliability of sliding window system. Computation of probability by interval-valued is most uses but universal generating function method given improved results within it. An example is also taken at the end to demonstrate the system.


2020 ◽  
Vol 39 (6) ◽  
pp. 8357-8364
Author(s):  
Thompson Stephan ◽  
Ananthnarayan Rajappa ◽  
K.S. Sendhil Kumar ◽  
Shivang Gupta ◽  
Achyut Shankar ◽  
...  

Vehicular Ad Hoc Networks (VANETs) is the most growing research area in wireless communication and has been gaining significant attention over recent years due to its role in designing intelligent transportation systems. Wireless multi-hop forwarding in VANETs is challenging since the data has to be relayed as soon as possible through the intermediate vehicles from the source to destination. This paper proposes a modified fuzzy-based greedy routing protocol (MFGR) which is an enhanced version of fuzzy logic-based greedy routing protocol (FLGR). Our proposed protocol applies fuzzy logic for the selection of the next greedy forwarder to forward the data reliably towards the destination. Five parameters, namely distance, direction, speed, position, and trust have been used to evaluate the node’s stability using fuzzy logic. The simulation results demonstrate that the proposed MFGR scheme can achieve the best performance in terms of the highest packet delivery ratio (PDR) and minimizes the average number of hops among all protocols.


2018 ◽  
Vol 4 (10) ◽  
pp. 10
Author(s):  
Ankur Mishra ◽  
Aayushi Priya

Transportation or transport sector is a legal source to take or carry things from one place to another. With the passage of time, transportation faces many issues like high accidents rate, traffic congestion, traffic & carbon emissions air pollution, etc. In some cases, transportation sector faced alleviating the brutality of crash related injuries in accident. Due to such complexity, researchers integrate virtual technologies with transportation which known as Intelligent Transport System. Intelligent Transport Systems (ITS) provide transport solutions by utilizing state-of-the-art information and telecommunications technologies. It is an integrated system of people, roads and vehicles, designed to significantly contribute to improve road safety, efficiency and comfort, as well as environmental conservation through realization of smoother traffic by relieving traffic congestion. This paper aims to elucidate various aspects of ITS - it's need, the various user applications, technologies utilized and concludes by emphasizing the case study of IBM ITS.


2020 ◽  
Vol 19 (11) ◽  
pp. 2116-2135
Author(s):  
G.V. Savin

Subject. The article considers functioning and development of process flows of transportation and logistics system of a smart city. Objectives. The study identifies factors and dependencies of the quality of human life on the organization and management of stream processes. Methods. I perform a comparative analysis of previous studies, taking into account the uniquely designed results, and the econometric analysis. Results. The study builds multiple regression models that are associated with stream processes, highlights interdependent indicators of temporary traffic and pollution that affect the indicator of life quality. However, the identified congestion indicator enables to predict the time spent in traffic jams per year for all participants of stream processes. Conclusions. The introduction of modern intelligent transportation systems as a component of the transportation and logistics system of a smart city does not fully solve the problems of congestion in cities at the current rate of urbanization and motorization. A viable solution is to develop cooperative and autonomous intelligent transportation systems based on the logistics approach. This will ensure control over congestion, the reduction of which will contribute to improving the life quality of people in urban areas.


Sign in / Sign up

Export Citation Format

Share Document