scholarly journals A Simplified Method to Avoid Shadows at Parabolic-Trough Solar Collectors Facilities

Symmetry ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 278 ◽  
Author(s):  
Nuria Novas ◽  
Aránzazu Fernández-García ◽  
Francisco Manzano-Agugliaro
Keyword(s):  
Large Scale ◽  
Small Scale ◽  
Parabolic Trough ◽  
Standard Case ◽  
Global Environmental Problems ◽  
Large Size ◽  
Global Environmental ◽  
Heating Water ◽  
Tracking Movement

Renewable energy today is no longer just an affordable alternative, but a requirement for mitigating global environmental problems such as climate change. Among renewable energies, the use of solar energy is one of the most widespread. Concentrating Solar Power (CSP) systems, however, is not yet fully widespread despite having demonstrated great efficiency, mainly thanks to parabolic-trough collector (PTC) technology, both on a large scale and on a small scale for heating water in industry. One of the main drawbacks to this energy solution is the large size of the facilities. For this purpose, several models have been developed to avoid shadowing between the PTC lines as much as possible. In this study, the classic shadowing models between the PTC rows are reviewed. One of the major challenges is that they are studied geometrically as a fixed installation, while they are moving facilities, as they have a tracking movement of the sun. In this work, a new model is proposed to avoid shadowing by taking into account the movement of the facilities depending on their latitude. Secondly, the model is tested to an existing facility as a real case study located in southern Spain. The model is applied to the main existing installations in the northern hemisphere, thus showing the usefulness of the model for any PTC installation in the world. The shadow projected by a standard, the PTC (S) has been obtained by means of a polynomial approximation as a function of the latitude (Lat) given by S = 0.001 − Lat2 + 0.0121 − Lat + 10.9 with R2 of 99.8%. Finally, the model has been simplified to obtain in the standard case the shadows in the running time of a PTC facility.

scholarly journals Supply chain resilience in a developing country context: a case study on the interconnectedness of threats, strategies and outcomes

2017 ◽  
Vol 22 (6) ◽  
pp. 486-505 ◽  
Author(s):  
Benjamin Tukamuhabwa ◽  
Mark Stevenson ◽  
Jerry Busby
Keyword(s):  
Supply Chain ◽  
Developing Country ◽  
Large Scale ◽  
Empirical Studies ◽  
Small Scale ◽  
Supply Network ◽  
Catastrophic Events ◽  
Content Type ◽  
Supply Chain Resilience

Purpose In few prior empirical studies on supply chain resilience (SCRES), the focus has been on the developed world. Yet, organisations in developing countries constitute a significant part of global supply chains and have also experienced the disastrous effects of supply chain failures. The purpose of this paper is therefore to empirically investigate SCRES in a developing country context and to show that this also provides theoretical insights into the nature of what is meant by resilience. Design/methodology/approach Using a case study approach, a supply network of 20 manufacturing firms in Uganda is analysed based on a total of 45 interviews. Findings The perceived threats to SCRES in this context are mainly small-scale, chronic disruptive events rather than discrete, large-scale catastrophic events typically emphasised in the literature. The data reveal how threats of disruption, resilience strategies and outcomes are inter-related in complex, coupled and non-linear ways. These interrelationships are explained by the political, cultural and territorial embeddedness of the supply network in a developing country. Further, this embeddedness contributes to the phenomenon of supply chain risk migration, whereby an attempt to mitigate one threat produces another threat and/or shifts the threat to another point in the supply network. Practical implications Managers should be aware, for example, of potential risk migration from one threat to another when crafting strategies to build SCRES. Equally, the potential for risk migration across the supply network means managers should look at the supply chain holistically because actors along the chain are so interconnected. Originality/value The paper goes beyond the extant literature by highlighting how SCRES is not only about responding to specific, isolated threats but about the continuous management of risk migration. It demonstrates that resilience requires both an understanding of the interconnectedness of threats, strategies and outcomes and an understanding of the embeddedness of the supply network. Finally, this study’s focus on the context of a developing country reveals that resilience should be equally concerned both with smaller in scale, chronic disruptions and with occasional, large-scale catastrophic events.

scholarly journals LANDSCAPE DESIGN FOR SUSTAINABILITY AND ECOSYSTEM SERVICES IN AN URBAN ENVIRONMENT: CASE STUDY OF TEHRAN AND HIS KAN RIVER

2020 ◽  
Author(s):  
Ilda Vagge ◽  
◽  
Gioia Maddalena Gibelli ◽  
Alessio Gosetti Poli ◽  
◽  
...  
Keyword(s):  
Ecosystem Services ◽  
Large Scale ◽  
Management Practices ◽  
Natural Capital ◽  
Landscape Design ◽  
Green Spaces ◽  
Small Scale ◽  
Design For Sustainability ◽  
Holistic Method

The authors, with the awareness that climate change affects and changes the landscape, wanted to investigate how these changes are occurring within the metropolitan area of Tehran. Trying to keep a holistic method that embraces different disciplines, reasoning from large scale to small scale, the authors tried to study the main problems related to water scarcity and loss of green spaces. Subsequently they dedicated themselves to the identification of the present and missing ecosystem services, so that they could be used in the best possible way as tools for subsequent design choices. From the analysis obtained, the authors have created a masterplan with the desire to ensure a specific natural capital, the welfare of ecosystem services, and at the same time suggest good water management practices. It becomes essential to add an ecological accounting to the economic accounting, giving dignity to the natural system and the ecosystem services that derive from it.

Million Dollar Pandas

2016 ◽  
Author(s):  
Peter Dauvergne
Keyword(s):  
Round Table ◽  
Small Scale ◽  
Business Partnerships ◽  
Global Environmental Problems ◽  
Global Environmental ◽  
The World ◽  
Certification Organizations ◽  
The One ◽  
Market Solutions ◽  
Business As Usual

This chapter analyzes the turn within mainstream environmentalism toward business partnerships, cause marketing, professional fundraising, and the co-branding of products. The chapter further examines the role of nongovernmental organizations in setting up and running eco-labeling and eco-certification organizations. WWF, also known as the World Wildlife Fund and the World Wide Fund for Nature, is a leader in the nongovernmental embrace of business, markets, and certification as ways to conserve nature and improve environmental conditions. Certification standards, such as those of the Marine Stewardship Council and the Round Table on Responsible Soy, are creating some modest reforms to business practices. NGO-business partnerships, such as the one between WWF and Coca-Cola, are also producing some small-scale benefits. But partnering with business and relying on market solutions risks legitimizing business as usual as well as shifting responsibility for global environmental problems onto consumers, a weak global force of change compared to the forces of unsustainability.

Leveraging the Cloud for Large-Scale Software Testing – A Case Study

2012 ◽  
pp. 252-279 ◽  
Author(s):  
Anjan Pakhira ◽  
Peter Andras
Keyword(s):  
Large Scale ◽  
Analysis Data ◽  
System Level ◽  
Small Scale ◽  
Test Cases ◽  
Software Life Cycle ◽  
Technical Issues ◽  
Wide Scale ◽  
Set Up

Testing is a critical phase in the software life-cycle. While small-scale component-wise testing is done routinely as part of development and maintenance of large-scale software, the system level testing of the whole software is much more problematic due to low level of coverage of potential usage scenarios by test cases and high costs associated with wide-scale testing of large software. Here, the authors investigate the use of cloud computing to facilitate the testing of large-scale software. They discuss the aspects of cloud-based testing and provide an example application of this. They describe the testing of the functional importance of methods of classes in the Google Chrome software. The methods that we test are predicted to be functionally important with respect to a functionality of the software. The authors use network analysis applied to dynamic analysis data generated by the software to make these predictions. They check the validity of these predictions by mutation testing of a large number of mutated variants of the Google Chrome. The chapter provides details of how to set up the testing process on the cloud and discusses relevant technical issues.

Change

2020 ◽  
pp. 310-338
Author(s):  
Hans-Jörg Schmid
Keyword(s):  
Large Scale ◽  
Language Change ◽  
Small Scale ◽  
Systematic Description ◽  
Change Direction ◽  
History Of

This chapter discusses how the Entrenchment-and-Conventionalization Model explains language change. First, it is emphasized that not only innovation and variation, but also the frequency of repetition can serve as important triggers of change. Conventionalization and entrenchment processes can interact and be influenced by numerous forces in many ways, resulting in various small-scale processes of language change, which can stop, change direction, or even become reversed. This insight serves as a basis for the systematic description of nine basic modules of change which differ in the ways in which they are triggered and controlled by processes and forces. Large-scale pathways of change such as grammaticalization, lexicalization, pragmaticalization, context-induced change, or colloquialization and standardization are all explained by reference to these modules. The system is applied in a case study on the history of do-periphrasis.

scholarly journals Noise assessment of the small-scale wind farm

2019 ◽  
Vol 112 ◽  
pp. 02011
Author(s):  
Cristian-Gabriel Alionte ◽  
Daniel-Constantin Comeaga
Keyword(s):  
Power Systems ◽  
Large Scale ◽  
Wind Farm ◽  
Wind Farms ◽  
Small Scale ◽  
Large Power ◽  
Small Power ◽  
Noise Assessment ◽  
The Impact

The importance of renewable energy and especially of eolian systems is growing. For this reason, we propose the investigation of an important pollutant - the noise, which has become so important that European Commission and European Parliament introduced Directive 2002/49/CE relating to the assessment and management of environmental noise. So far, priority has been given to very large-scale systems connected to national energy systems, wind farms whose highly variable output power could be regulated by large power systems. Nowadays, with the development of small storage capacities, it is feasible to install small power wind turbines in cities of up to 10,000 inhabitants too. As a case study, we propose a simulation for a rural locality where individual wind units could be used. This specific case study is interesting because it provides a new perspective of the impact of noise on the quality of life when the use of this type of system is implemented on a large scale. This option, of distributed and small power wind turbine, can be implemented in the future as an alternative or an adding to the common systems.

scholarly journals Thermal balance of large scale parabolic trough plants: A case study

Solar Energy ◽  
2019 ◽  
Vol 190 ◽  
pp. 69-81 ◽  
Author(s):  
A.J. Sánchez ◽  
A.J. Gallego ◽  
J.M. Escaño ◽  
E.F. Camacho
Keyword(s):  
Large Scale ◽  
Thermal Balance ◽  
Parabolic Trough

SMALL SCALE PILOT PROJECT AS A TOOL FOR PLANNING LARGE SCALE RESTORATION

2008 ◽  
Vol 2008 (1) ◽  
pp. 1163-1169
Author(s):  
Leslie J. Craig ◽  
Tom Pride
Keyword(s):  
Large Scale ◽  
Oyster Reef ◽  
Pilot Project ◽  
Lessons Learned ◽  
Small Scale ◽  
Pilot Studies ◽  
Restoration Project ◽  
Survival And Growth ◽  
Oyster Restoration

ABSTRACT The use of pilot studies can be a useful tool in determining the most appropriate location, method and design for a large scale restoration project. This paper provides a case study where Trustees implemented a small pilot project and feasibility study to determine the best approach for a large scale oyster reef creation project. While the specific case study is the result of a CERCLA settlement (Alafia River Acid Spill of 1997), this model is transferable to other instances where Trustees are scoping for the most appropriate sites and methods to conduct settlement funded restoration. The Restoration Plan and Environmental Assessment on which the case settlement was based called for creation of approximately 4 acres of oyster reef in addition to 4 acres of estuarine marsh restoration. Through an initial scoping process, the Trustees determined that more information was needed to select the most appropriate locations and techniques to implement the large scale oyster restoration project. The Trustees identified 3 general locations with potential for larger scale oyster reef creation. A portion of settlement funding was used to contract for construction and monitoring of an oyster reef pilot project to examine the efficacy of oyster reef construction at the three locations using 4 different cultch materials. At each of the locations, 4 small reefs (approximately 75’ × 20’) were constructed and monitored for spat set, oyster survival and growth as well as subsidence. A baseline construction report and final monitoring report detailed the results. In addition, a separate report was completed that outlined the feasibility of constructing a 4 acre oyster reef in Hillsborough Bay, FL. This report included several construction considerations such as local sources and costs of cultch materials, shipping/transport, staging areas, construction equipment as well as potential local contractors. This paper reports the results of the oyster pilot project and feasibility report as well as lessons learned from each approach.

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