scholarly journals A Hybrid Tabu Search and 2-opt Path Programming for Mission Route Planning of Multiple Robots under Range Limitations

Electronics ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 534 ◽  
Author(s):  
Meng-Tse Lee ◽  
Bo-Yu Chen ◽  
Ying-Chih Lai
Keyword(s):  
Tabu Search ◽  
Large Scale ◽  
Optimal Path ◽  
Route Planning ◽  
Unmanned Vehicles ◽  
Programming Algorithm ◽  
Second Phase ◽  
Two Phase ◽  
Exchange Method ◽  
Unmanned Vehicle

The application of an unmanned vehicle system allows for accelerating the performance of various tasks. Due to limited capacities, such as battery power, it is almost impossible for a single unmanned vehicle to complete a large-scale mission area. An unmanned vehicle swarm has the potential to distribute tasks and coordinate the operations of many robots/drones with very little operator intervention. Therefore, multiple unmanned vehicles are required to execute a set of well-planned mission routes, in order to minimize time and energy consumption. A two-phase heuristic algorithm was used to pursue this goal. In the first phase, a tabu search and the 2-opt node exchange method were used to generate a single optimal path for all target nodes; the solution was then split into multiple clusters according to vehicle numbers as an initial solution for each. In the second phase, a tabu algorithm combined with a 2-opt path exchange was used to further improve the in-route and cross-route solutions for each route. This diversification strategy allowed for approaching the global optimal solution, rather than a regional one with less CPU time. After these algorithms were coded, a group of three robot cars was used to validate this hybrid path programming algorithm.

scholarly journals A Study on Applicability of the Scrum Framework for Large Software Projects

2021 ◽  
Author(s):  
Jaweria Sultana
Keyword(s):  
Literature Review ◽  
Systematic Literature Review ◽  
Large Scale ◽  
Primary Objective ◽  
Work Rate ◽  
Communication Overhead ◽  
Second Phase ◽  
Software Projects ◽  
Two Phase ◽  
Good Communication

The primary objective of this research is to investigate the adaptability of the Scrum framework for large scale projects. A two phase approach has been undertaken towards the goal. The first phase involves conducting a systematic literature review to identify and elaborate scaling practices used in the current industry. The review also identifies the challenges faced by the developers when the Scrum framework is used for the development of large projects. The second phase involves the construction of a simulation model to analyze the dynamic behavior of the Scrum framework for large projects. The systematic literature review revealed that the major challenge while scaling Scrum is ensuring good communication among project members. The communication overhead was incorporated in the system dynamic model of the Scrum framework. The simulation results showed that there is a reduction in work rate when number of personnel is increased due to the increasing communication overhead.

Towards Rapid Redesign: Pattern-Based Design Diagnostics for Large-Scale and Complex Redesign Problems

2005 ◽  
Author(s):  
Li Chen ◽  
Ashish Macwan
Keyword(s):  
Large Scale ◽  
Functional Dependence ◽  
Agile Manufacturing ◽  
Design Model ◽  
Second Phase ◽  
Phase Decomposition ◽  
Two Phase ◽  
Dependency Matrix ◽  
Solution Approach ◽  
Coupling Structure

This paper presents our continued research efforts towards developing a decomposition-based solution approach for rapid computational redesign to support agile manufacturing of evolutionary products. By analogy to the practices used for physical machines, the proposed approach involves two general steps: diagnosis and repair. This paper focuses on the diagnosis step. for which a two-phase decomposition method is developed. The first phase, called design dependency analysis, systematizes and reorganizes the intrinsic coupling structure of the existing design model by analyzing and reordering the design dependency matrix (DDM) used to represent the functional dependence and couplings inherent in the design model. The second phase, called redesign partitioning analysis, uses this result to generate alternative redesign pattern solutions through a three-stage procedure. Each pattern solution delimits the portions of the design model that need to be re-computed. An example problem concerning the redesign of an automobile powertrain is used for method illustration. Our seed paper has presented a method for selecting the optimal redesign pattern solution from the alternatives generated through redesign partitioning analysis, and a sequel paper will discuss how to generate a corresponding re-computation strategy and redesign plan (redesign shortcut roadmap).

scholarly journals A Joint Optimization Strategy of Coverage Planning and Energy Scheduling for Wireless Rechargeable Sensor Networks

Processes ◽  
2020 ◽  
Vol 8 (10) ◽  
pp. 1324
Author(s):  
Cheng Gong ◽  
Chao Guo ◽  
Haitao Xu ◽  
Chengcheng Zhou ◽  
Xiaotao Yuan
Keyword(s):  
Sensor Networks ◽  
Communication Networks ◽  
Energy Supply ◽  
Large Scale ◽  
Joint Optimization ◽  
Second Phase ◽  
Optimization Strategy ◽  
Two Phase ◽  
Game Equilibrium ◽  
Wireless Rechargeable Sensor Networks

Wireless Sensor Networks (WSNs) have the characteristics of large-scale deployment, flexible networking, and many applications. They are important parts of wireless communication networks. However, due to limited energy supply, the development of WSNs is greatly restricted. Wireless rechargeable sensor networks (WRSNs) transform the distributed energy around the environment into usable electricity through energy collection technology. In this work, a two-phase scheme is proposed to improve the energy management efficiency for WRSNs. In the first phase, we designed an annulus virtual force based particle swarm optimization (AVFPSO) algorithm for area coverage. It adopts the multi-parameter joint optimization method to improve the efficiency of the algorithm. In the second phase, a queuing game-based energy supply (QGES) algorithm was designed. It converts energy supply and consumption into network service. By solving the game equilibrium of the model, the optimal energy distribution strategy can be obtained. The simulation results show that our scheme improves the efficiency of coverage and energy supply, and then extends the lifetime of WSN.

3D MС Simulation of Grain Growth Kinetics and the Zener Limit in Polycrystals

2014 ◽  
Vol 598 ◽  
pp. 8-12
Author(s):  
K.R. Phaneesh ◽  
Anirudh Bhat ◽  
Gautam Mukherjee ◽  
Kishore T. Kashyap
Keyword(s):  
Monte Carlo ◽  
Grain Growth ◽  
Growth Kinetics ◽  
Large Scale ◽  
Volume Fraction ◽  
Growth Exponent ◽  
Cube Root ◽  
Second Phase ◽  
Two Phase ◽  
Second Phase Particles

Large scale Potts model Monte Carlo simulation was carried on 3-dimensional square lattices of 1003 and 2003 sizes using the Metropolis algorithm to study grain growth behavior. Simulations were carried out to investigate both growth kinetics as well as the Zener limit in two-phase polycrystals inhibited in growth by second phase particles of single-voxel size. Initially the matrices were run to 10,000 Monte Carlo steps (MCS) to check the growth kinetics in both single phase and two-phase poly-crystals. Grain growth exponent values obtained as a result have shown to be highest (~ 0.4) for mono-phase materials while the value decreases with addition of second phase particles. Subsequently the matrices were run to stagnation in the presence of second phase particles of volume fractions ranging from 0.001to 0.1. Results obtained have shown a cube root dependence of the limiting grain size over the particle volume fraction thus reinforcing earlier 3D simulation efforts. It was observed that there was not much difference in the values of either growth kinetics or the Zener limit between 1003 and 2003 sized matrices, although the results improved mildly with size.

scholarly journals Beacon-Based Hybrid Routing Protocol for Large-Scale Unmanned Vehicle Ad Hoc Network

Electronics ◽  
2021 ◽  
Vol 10 (24) ◽  
pp. 3129
Author(s):  
Weiwei Mu ◽  
Guang Li ◽  
Yulin Ma ◽  
Rendong Wang ◽  
Yanbo Li ◽  
...  
Keyword(s):  
Routing Protocol ◽  
Large Scale ◽  
Unmanned Vehicles ◽  
Maintenance Cost ◽  
Communication Link ◽  
Unmanned Vehicle ◽  
Hybrid Routing ◽  
Communication Links ◽  
Hybrid Routing Protocol ◽  
Vehicle Network

In this paper, we designed a beacon-based hybrid routing protocol to adapt to the new forms of intelligent warfare, accelerate the application of unmanned vehicles in the military field, and solve the problems such as high maintenance cost, path failure, and repeated routing pathfinding in large-scale unmanned vehicle network communications for new battlefields. This protocol used the periodic broadcast pulses initiated by the beacon nodes to provide synchronization and routing to the network and established a spanning tree through which the nodes communicated with each other. An NS3 platform was used to build a dynamic simulation environment of service data to evaluate the network performance. The results showed that when it was used in a range of 5 ~ 35 communication links, the beacon-based routing protocol’s PDR was approximately 10% higher than that of AODV routing protocol. At 5 ~ 50 communication links, the result was approximately 20% higher than the DSDV routing protocol. The routing load was not related to the number of nodes and communication link data and the protocol had better performance than traditional AODV and DSDV routing protocol, which reduced the cost of the routing protocol and effectively improved the stability and reliability of the network. The protocol we designed is more suitable for the scenarios of large-scale unmanned vehicle network communication in the future AI battlefield.

Intelligent Image-Based Gas-Liquid Two-Phase Flow Regime Recognition

2012 ◽  
Vol 134 (6) ◽  
Author(s):  
Soheil Ghanbarzadeh ◽  
Pedram Hanafizadeh ◽  
Mohammad Hassan Saidi
Keyword(s):  
Large Scale ◽  
Two Phase Flow ◽  
Extraction Procedure ◽  
Flow Regimes ◽  
Flow Patterns ◽  
Image Processing Technique ◽  
Test Facility ◽  
Second Phase ◽  
Phase Flow ◽  
Two Phase

Identification of different flow regimes in industrial systems operating under two-phase flow conditions is necessary in order to safely design and optimize their performance. In the present work, experiments on two-phase flow have been performed in a large scale test facility with the length of 6 m and diameter of 5 cm. Four main flow regimes have been observed in vertical air-water two-phase flow at moderate superficial velocities of gas and water namely: Bubbly, Slug, Churn, and Annular. An image processing technique was used to extract information from each picture. This information includes the number of bubbles or objects, area, perimeter, as well as the height and width of objects (second phase). In addition, a texture feature extraction procedure was applied to images of different regimes. Some features which were adequate for regime identification were extracted such as contrast, energy, entropy, etc. To identify flow regimes, a fuzzy interface was introduced using characteristic of second phase in picture. Furthermore, an Adaptive Neuro Fuzzy (ANFIS) was used to identify flow patterns using textural features of images. The experimental results show that these methods can accurately identify the flow patterns in a vertical pipe.

scholarly journals A Vehicle Route Planning Method of Two-Phase Large-Scale Crowd Evacuation in Typhoon Relief Activities

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Sha-lei Zhan ◽  
Liang Chen ◽  
Ping-Kuo Chen ◽  
Yong Ye
Keyword(s):  
Large Scale ◽  
Route Planning ◽  
Resource Limitation ◽  
Route Selection ◽  
Two Phase ◽  
Destructive Effect ◽  
Selection Scheme ◽  
Vehicle Route ◽  
Crowd Evacuation ◽  
Secondary Disasters

Large-scale crowd evacuation is an important measure guaranteeing the safety of disaster-stricken victims in typhoon relief activities. Decision-making related to antityphoon crowd evacuation must take full consideration of the destructive effect of typhoons and their secondary disasters, time urgency, and resource limitation. To give full play to limited vehicle resources, the influence of a typhoon and its secondary disasters on antityphoon evacuation are mainly manifested during the execution of evacuation tasks in this article. The shortest time spent in completing all evacuation tasks was taken as the objective. Then, a vehicle route selection model for two-phase large-scale antityphoon crowd evacuation was built under an uncertain environment, and a matrix encoding–based genetic algorithm was designed to solve the model. Under the background of Super Typhoon Meranti in 2016, the model and algorithm were applied to crowd evacuation in a typhoon in Xiamen for a simulated analysis. Results indicate that in typhoon relief activities, emergency decision makers can use the proposed method to acquire a scientific and reasonable route selection scheme for antityphoon crowd evacuation according to related typhoon disaster data.

scholarly journals PENGEMBANGAN ALAT PERAGA KOTAK ENERGI MODEL INKUIRI TERBIMBING (APKEMIT) SEBAGAI PENUNJANG PEMBELAJARAN FISIKA SMA PADA MATERI SUHU DAN KALOR

2015 ◽  
Vol 1 (2) ◽  
Author(s):  
Budiono Basuki ◽  
Aris Doyan ◽  
Ahmad Harjono
Keyword(s):  
Large Scale ◽  
Development Stage ◽  
Learning Activity ◽  
Second Phase ◽  
Two Phase ◽  
Gain Score ◽  
Pilot Testing ◽  
Tenth Graders ◽  
Testing Stage ◽  
Limited Testing

The purpose of this research is to develop APKEMIT as learning tool for high school physics on temperature and heat concepts. This study used Borg & Gall approach on R & D which includes the step of development, pilot testing, and final testing. In the development stage, five APKEMIT models are produced: PKTSB, PW, PPSTUB, PK, and AB. Pilot testing stage is divided into two phase, limited testing and large scale testing. The first limited testing carried out on 6 eleventh grade science students in SMA 3 Mataram. The second phase carried on 2 groups (12 students) of accelerated tenth graders in SMA Negeri 1 Woha. Large-scale trials given to 8 groups (46 students) of tenth graders in SMA Negeri 3 Mataram. Pilot testing shows that APKEMIT is very good and ready to be used in learning activity. APKEMIT final testing stage is the stage to determine the effect of APKEMIT on the improvement of learning outcomes, which is determined by the Gain Score. Analysis shows that the gain of each model is: PKTSB Score of 0.50 (medium), PW of 0.15 (low), PPSTUB of 0.40 (medium), PK at 12:27 (low), AB of 0.34 (medium) and overall Gain Score at 0:36 (medium). This development received good response from the students with score 80.8% and according to observers, learning process has been going very well. The result of research  and validation of test show that the developed APKEMIT become as references in subject temperature and heats concepts.

scholarly journals A Study on Applicability of the Scrum Framework for Large Software Projects

2021 ◽  
Author(s):  
Jaweria Sultana
Keyword(s):  
Literature Review ◽  
Systematic Literature Review ◽  
Large Scale ◽  
Primary Objective ◽  
Work Rate ◽  
Communication Overhead ◽  
Second Phase ◽  
Software Projects ◽  
Two Phase ◽  
Good Communication

The primary objective of this research is to investigate the adaptability of the Scrum framework for large scale projects. A two phase approach has been undertaken towards the goal. The first phase involves conducting a systematic literature review to identify and elaborate scaling practices used in the current industry. The review also identifies the challenges faced by the developers when the Scrum framework is used for the development of large projects. The second phase involves the construction of a simulation model to analyze the dynamic behavior of the Scrum framework for large projects. The systematic literature review revealed that the major challenge while scaling Scrum is ensuring good communication among project members. The communication overhead was incorporated in the system dynamic model of the Scrum framework. The simulation results showed that there is a reduction in work rate when number of personnel is increased due to the increasing communication overhead.

A Comparison of Tem and Apfim to the Interpretation of Modulated Microstructures

1985 ◽  
Vol 43 ◽  
pp. 70-71
Author(s):  
M.G. Burke ◽  
M.K. Miller
Keyword(s):  
Low Temperature ◽  
Microstructural Characterization ◽  
Superlattice Reflection ◽  
High Volume ◽  
Atom Probe ◽  
Dark Field ◽  
Miscibility Gap ◽  
Second Phase ◽  
Two Phase ◽  
Probe Field

Interpretation of fine-scale microstructures containing high volume fractions of second phase is complex. In particular, microstructures developed through decomposition within low temperature miscibility gaps may be extremely fine. This paper compares the morphological interpretations of such complex microstructures by the high-resolution techniques of TEM and atom probe field-ion microscopy (APFIM).The Fe-25 at% Be alloy selected for this study was aged within the low temperature miscibility gap to form a <100> aligned two-phase microstructure. This triaxially modulated microstructure is composed of an Fe-rich ferrite phase and a B2-ordered Be-enriched phase. The microstructural characterization through conventional bright-field TEM is inadequate because of the many contributions to image contrast. The ordering reaction which accompanies spinodal decomposition in this alloy permits simplification of the image by the use of the centered dark field technique to image just one phase. A CDF image formed with a B2 superlattice reflection is shown in fig. 1. In this CDF micrograph, the the B2-ordered Be-enriched phase appears as bright regions in the darkly-imaging ferrite. By examining the specimen in a [001] orientation, the <100> nature of the modulations is evident.

Sign in / Sign up

Export Citation Format

Share Document