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A green scheduling algorithm for the distributed flowshop problem
Get PDFIn recent years, sustainable development and green manufacturing have attracted widespread attention to environmental problems becoming increasingly serious. Meanwhile, affected by the intensification of market competition and economic globalization, distributed manufacturing systems have become increasingly common. This paper addresses the energy-efficient scheduling of the distributed permutation flowshop (EEDPFSP) with the criteria of minimizing both total flow time and total energy consumption. Considering the distributed and multi-objective optimization complexity, an improved NSGAII algorithm (INSGAII) is proposed. First, we analyze the problem-specific characteristics and designed new operators based on the knowledge of the problem. Second, four constructive heuristic algorithms are proposed to produce high-quality initial solutions. Third, inspired by the artificial bee colony algorithm, we propose a new colony generation method using the operators designed. Fourth, a local intensification is designed for exploiting better non-dominated solutions. The influence of parameter settings is investigated by experiments to determine the optimal parameter configuration of the INSGAII. Finally, a large number of computational tests and comparisons have been carried out to verify the effectiveness of the proposed INSGAII in solving EEDPFSP
Integer and constraint programming model formulations for flight-gate assignment problem
No full textFlight-gate assignment problems are complex real world problems involving different constraints. Some of these constraints include plane-gate eligibility, assigning planes of the same airline and planes getting service from the same ground handling companOperations Research & Management ScienceOperations Research & Management Scienc
A green scheduling algorithm for the distributed flowshop problem
No full textIn recent years, sustainable development and green manufacturing have attracted widespread attention to environmental problems becoming increasingly serious. Meanwhile, affected by the intensification of market competition and economic globalization, distributed manufacturing systems have become increasingly common. This paper addresses the energy-efficient scheduling of the distributed permutation flowshop (EEDPFSP) with the criteria of minimizing both total flow time and total energy consumption. Considering the distributed and multi-objective optimization complexity, an improved NSGAII algorithm (INSGAII) is proposed. First, we analyze the problem-specific characteristics and designed new operators based on the knowledge of the problem. Second, four constructive heuristic algorithms are proposed to produce high-quality initial solutions. Third, inspired by the artificial bee colony algorithm, we propose a new colony generation method using the operators designed. Fourth, a local intensification is designed for exploiting better non-dominated solutions. The influence of parameter settings is investigated by experiments to determine the optimal parameter configuration of the INSGAII. Finally, a large number of computational tests and comparisons have been carried out to verify the effectiveness of the proposed INSGAII in solving EEDPFSP
The production of space through transmediated identity practices: Spatial self in Instagram at Mavibahce Shopping Centre in Izmir
No full textWidespread use of locative media and its integration with social media applications has provided individuals with the new ways of identity practices. Through checking in at locations, uploading still and moving images of/with certain spaces, and adding haCommunicationCommunicatio
How Loud and Clear Rung the Alarm Bell: The Communication Efforts of WHO on the Beginning of COVID-19 Outbreak
Get PDFs seen clearly from the coronavirus disease 2019 (COVID-19) pandemic, health is an important foreign policy and diplomatic issue connected with security, economic well-being, and international development. According to risk communication researchers, effective, transparent, and timely information sharing is the most important tool after vaccines for responding to pandemics. This study aims to start a scholarly discussion on the risk communication efforts of the World Health Organization (WHO) during the COVID-19 outbreak. We analyzed WHO’s communication efforts during the first 3 months of the COVID-19 pandemic. As the leading international health organization, WHO was responsible for providing rapid, up-to-date, and credible information for the public and the media. The selected research items were 42 news releases and statements provided by WHO between December 31, 2019, and March 30, 2020. These were subjected to qualitative and quantitative content analyses using the NVivo 12 qualitative analysis software program for coding. The data were coded under 6 variables (date of publication, topics, frequency, wording of the COVID-19 outbreak, sourcing, and themes of the releases). While 54.7% of WHO's communications were devoted to the COVID-19 outbreak, more than half were not issued until March. That is, instead of early risk communication and clear warnings about the outbreak, WHO acted overcautiously, preferring messages related to solidarity and cooperation during the most devastating pandemic of the 21st century
Propose a Polynomial Time Algorithm for Total Completion Time Objective
Get PDFIn this study, we integrate deteriorate jobs with repair&maintenance activity on a single machine scheduling subject to total completion time. This work has more than one motivation. First, jobs are assigned to machines in an automated production line. Later, to schedule the maintenance activities, if needed, to prevent machinery from breaking down later. There are some important mathematical models to solve this combination. However, due to the complexity of the problem which is Np-hard, a polynomial algorithm should be needed for solving large problems. Therefore, this article introduces several polnomial algorithms to determine the order of things best. With using these algorithms, it will be possible to determine where to assign to the schedule, taking into account the number of maintenance activities required and their optimum total completion time
Geometric and analytical design of angulated scissor structures
No full textDeployable scissor structures are capable of large geometric transformations between predefined configurations thanks to their extension and rotation properties. These structures are formed by connecting translational, polar or angulated units that are composed of scissor-like elements. The studies especially on the angulated scissor structures mostly concentrate on developing certain types of planar or spatial structures; thus, they do not present a systematic form-finding method for different types of angulated units lying on different path-curves. This paper aims to introduce two design methods including geometrical method based on drawings and analytical method based on mathematical equations both for generating various angulated scissor structures and facilitating the design of asymmetric and polycentric structures. First, basic design principles of the angulated scissor structures are investigated. Then, proper solutions are proposed to design such planar structures using both geometrical and analytical methods. Various planar angulated scissor structures are generated lying on monocentric and polycentric curves or straight-line in the deployed, fully deployed, and undeployed configurations. Finally, a case study as a numerical model of a sunshade with monocentric curve is presented
