scholarly journals Optimization of biogas supply networks considering multiple objectives and auction trading prices of electricity

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Jafaru Musa Egieya ◽  
Lidija Čuček ◽  
Klavdija Zirngast ◽  
Adeniyi Jide Isafiade ◽  
Zdravko Kravanja
Keyword(s):  
Organic Fertilizer ◽  
Ghg Emissions ◽  
Multiple Objectives ◽  
Electricity Production ◽  
Mixed Integer ◽  
Illustrative Case ◽  
Supply Networks ◽  
Economic Profit ◽  
Biogas Plants ◽  
Illustrative Case Study

AbstractThis contribution presents an hourly-based optimization of a biogas supply network to generate electricity, heat and organic fertilizer while considering multiple objectives and auction trading prices of electricity. The optimization model is formulated as a mixed-integer linear programming (MILP) utilizing a four-layer biogas supply chain. The model accounts for biogas plants based on two capacity levels of methane to produce on average 1 ± 0.1 MW and 5 ± 0.2 MW electricity. Three objectives are put forward: i) maximization of economic profit, ii) maximization of economic profit while considering cost/benefits from greenhouse gas (GHG) emissions (economic+GHG profit) and iii) maximization of sustainability profit. The results show that the economic profit accrued on hourly-based auction trading prices is negative (loss), hence, four additional scenarios are put forward: i) a scenario whereby carbon prices are steadily increased to the prevalent eco-costs/eco-benefits of global warming; ii) a scenario whereby all the electricity auction trading prices are multiplied by certain factors to find the profitability breakeven factor, iii) a scenario whereby shorter time periods are applied, and investment cost of biogas storage is reduced showing a relationship between cost, volume of biogas stored and the variations in electricity production and (iv) a scenario whereby the capacity of the biogas plant is varied from 1 MW and 5 MW as it affects economics of the process. The models are applied to an illustrative case study of agricultural biogas plants in Slovenia where a maximum of three biogas plants could be selected. The results hence present the effects of the simultaneous relationship of economic profit, economic+GHG profit and sustainability profit on the supply and its benefit to decision-making.

Multi-objective and multi-period optimization of a regional timber supply network with uncertainty

2020 ◽  
Vol 50 (2) ◽  
pp. 203-214 ◽  
Author(s):  
Cheng Chen ◽  
Jianbang Gan ◽  
Zhengxiong Zhang ◽  
Rongzu Qiu
Keyword(s):  
Demand Uncertainty ◽  
Ghg Emissions ◽  
Fuzzy Linear Programming ◽  
Mixed Integer ◽  
Generic Model ◽  
Distribution Centers ◽  
Model Framework ◽  
Timber Supply ◽  
Supply Networks ◽  
The Cost

To assess the impacts of uncertainty and environmental objectives on the configuration of timber supply networks, we develop a generic multi-period, mixed-integer fuzzy linear programming model with demand uncertainty and two objectives of minimizing total transportation cost and greenhouse gas (GHG) emissions. We then use the triangular fuzzy number method to define the uncertain demands and convert the model into its equivalent auxiliary crisp counterpart. To derive Pareto solutions more efficiently, we propose the nondominated sorting genetic algorithm (NSGA-II) to solve the model. Finally, we apply the model framework and solution method to a real-world case of regional timber supply in Fujian, China, to demonstrate their applicability. The simulation results of the model show that trade-offs exist between total cost and GHG emissions and that the proper selection of the number and locations of distribution centers can help reduce both the cost and GHG emissions. Demand uncertainty and supply fluctuations across different time periods can increase the cost and GHG emissions. Our empirical results provide useful insights into the design and management of regional timber supply networks, and our generic model is applicable to the analysis of regional supply networks of other products or materials besides timber.

scholarly journals Modern Modeling Paradigms Using Generalized Disjunctive Programming

Processes ◽  
2019 ◽  
Vol 7 (11) ◽  
pp. 839 ◽  
Author(s):  
Qi Chen ◽  
Ignacio Grossmann
Keyword(s):  
Model Development ◽  
Logical Structure ◽  
Disjunctive Programming ◽  
Mixed Integer ◽  
Illustrative Case ◽  
Modeling Framework ◽  
Decomposition Scheme ◽  
Solution Strategies ◽  
Generalized Disjunctive Programming ◽  
Illustrative Case Study

Models involving decision variables in both discrete and continuous domain spaces are prevalent in process design. Generalized Disjunctive Programming (GDP) has emerged as a modeling framework to explicitly represent the relationship between algebraic descriptions and the logical structure of a design problem. However, fewer formulation examples exist for GDP compared to the traditional Mixed-Integer Nonlinear Programming (MINLP) modeling approach. In this paper, we propose the use of GDP as a modeling tool to organize model variants that arise due to characterization of different sections of an end-to-end process at different detail levels. We present an illustrative case study to demonstrate GDP usage for the generation of model variants catered to process synthesis integrated with purchasing and sales decisions in a techno-economic analysis. We also show how this GDP model can be used as part of a hierarchical decomposition scheme. These examples demonstrate how GDP can serve as a useful model abstraction layer for simplifying model development and upkeep, in addition to its traditional usage as a platform for advanced solution strategies.

Systemic Unsustainability as a Threat to Democracy

2020 ◽  
Author(s):  
Andrea Felicetti
Keyword(s):  
Research Agenda ◽  
Ecological Crisis ◽  
Illustrative Case ◽  
Sustainability Transition ◽  
Ways Of Thinking ◽  
Illustrative Case Study ◽  
New Research

Resilient socioeconomic unsustainability poses a threat to democracy whose importance has yet to be fully acknowledged. As the prospect of sustainability transition wanes, so does perceived legitimacy of institutions. This further limits representative institutions’ ability to take action, making democratic deepening all the more urgent. I investigate this argument through an illustrative case study, the 2017 People’s Climate March. In a context of resilient unsustainability, protesters have little expectation that institutions might address the ecological crisis and this view is likely to spread. New ways of thinking about this problem and a new research agenda are needed.

The Effects of Teaching Reflection Diaries on In-Service High School Teachers in Japan

Relay Journal ◽  
2020 ◽  
pp. 80-99
Author(s):  
Naoya Shibata
Keyword(s):  
High School ◽  
High School Teachers ◽  
Illustrative Case ◽  
Teaching Beliefs ◽  
Experienced Teacher ◽  
Female Teachers ◽  
Self Confidence ◽  
Research Findings ◽  
Illustrative Case Study

Although teaching reflection diaries (TRDs) are prevalent tools for teacher training, TRDs are rarely used in Japanese secondary educational settings. In order to delve into the effects of TRDs on teaching development, this illustrative case study was conducted with two female teachers (one novice, and one experienced) at a Japanese private senior high school. The research findings demonstrated that both in-service teachers perceived TRDs as beneficial tools for understanding their strengths and weaknesses. TRDs and class observations illustrated that the novice teacher raised their self-confidence in teaching and gradually changed their teaching activities. On the other hand, the experienced teacher held firm teaching beliefs based on their successful teaching experiences and were sometimes less willing to experiment with different approaches. However, they changed their teaching approaches when they lost balance between their class preparation and other duties. Accordingly, although teachers’ firm beliefs and successful experiences may sometimes become possible hindrances from using TRDs effectively, TRDs can be useful tools to train and help teachers realise their strengths and weaknesses.

Country of origin branding: an integrative perspective

2016 ◽  
Vol 25 (4) ◽  
pp. 322-336 ◽  
Author(s):  
Roderick J. Brodie ◽  
Maureen Benson-Rea
Keyword(s):  
Country Of Origin ◽  
Theoretical Framework ◽  
Illustrative Case ◽  
Business Relationships ◽  
Content Type ◽  
Brand Meaning ◽  
Value Propositions ◽  
Illustrative Case Study ◽  
Strategic Perspective

Purpose A new conceptualization of the process of country of origin (COO) branding based on fresh theoretical foundations is developed. This paper aims to provide a strategic perspective that integrates extant views of COO branding, based on identity and image, with a relational perspective based on a process approach to developing collective brand meaning. Design/methodology/approach A systematic review of the literature on COO branding and geographical indicators is undertaken, together with a review of contemporary research on branding. Our framework conceptualizes COO branding as an integrating process that aligns a network of relationships to co-create collective meaning for the brand’s value propositions. Findings An illustrative case study provides empirical evidence to support the new theoretical framework. Research limitations/implications Issues for further research include exploring and refining the theoretical framework in other research contexts and investigating broader issues about how COO branding influences self and collective interests in business relationships and industry networks. Practical implications Adopting a broadened perspective of COO branding enables managers to understand how identity and image are integrated with their business relationships in the context of developing collective brand meaning. Providing a sustained strategic advantage for all network actors, an integrated COO branding process extends beyond developing a distinctive identity and image. Originality/value Accepted consumer, product, firm and place level perspectives of COO branding are challenged by developing and verifying a new integrated conceptualization of branding.

scholarly journals A Hesitant Fuzzy Combined Compromise Solution Framework-Based on Discrimination Measure for Ranking Sustainable Third-Party Reverse Logistic Providers

2021 ◽  
Vol 13 (4) ◽  
pp. 2064
Author(s):  
Arunodaya Raj Mishra ◽  
Pratibha Rani ◽  
Raghunathan Krishankumar ◽  
Edmundas Kazimieras Zavadskas ◽  
Fausto Cavallaro ◽  
...  
Keyword(s):  
Reverse Logistics ◽  
Hybrid Approach ◽  
Third Party ◽  
Illustrative Case ◽  
Primary Concern ◽  
Compromise Solution ◽  
Fuzzy Environment ◽  
Criteria Weights ◽  
Reverse Logistic ◽  
Illustrative Case Study

Customers’ pressure, social responsibility, and government regulations have motivated the enterprises to consider the reverse logistics (RL) in their operations. Recently, companies frequently outsource their RL practices to third-party reverse logistics providers (3PRLPs) to concentrate on their primary concern and diminish costs. However, to select the suitable 3PRLP candidate requires a multi-criteria decision making (MCDM) process involving uncertainty owing to the presence of many associated aspects. In order to choose the most appropriate sustainable 3PRLP (S3PRLP), we introduce a hybrid approach based on the classical Combined Compromise Solution (CoCoSo) method and propose a discrimination measure within the context of hesitant fuzzy sets (HFSs). This approach offers a new process based on the discrimination measure for evaluating the criteria weights. The efficiency and practicability of the present approach are numerically demonstrated by solving an illustrative case study of S3PRLPs selection under a hesitant fuzzy environment. Moreover, sensitivity and comparative studies are presented to highlight the robustness and strength of the introduced methodology. The result of this work concludes that the introduced methodology can recommend a more feasible performance when facing with determinate and inconsistent knowledge and qualitative data.

Economic structure, power and institutions: A conceptual framework for analysing the historical transformation of US industrial strategy

2021 ◽  
pp. 102452942110154
Author(s):  
Mattia Tassinari
Keyword(s):  
Structural Change ◽  
Conceptual Framework ◽  
Economic Structure ◽  
Institutional Arrangements ◽  
Illustrative Case ◽  
Alexander Hamilton ◽  
The Government ◽  
Distribution Of Power ◽  
Illustrative Case Study

An industrial strategy emerges from possibilities for structural change, that depend on material constraints and opportunities afforded by economic structure, the distribution of power in society and the institutional arrangements organized at the political level. Building on a structural political economy perspective, this article develops a structure–power–institutions conceptual framework to describe how economic structure, the distribution of power, and institutions interact through a ‘circular process,’ which is useful for analysing the historical transformation of industrial strategy. In this framework, an industrial strategy refers to the institutional arrangements through which the government manages emerging conflicts or agreements between different powers and influences structural change. As an illustrative case study, the structure–power–institutions framework is applied to analyse the historical transformation of US industrial strategy from the era of Alexander Hamilton to that of Donald Trump.

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