Economy‐wide material system analysis: Mapping material flows through the economy

2021 ◽  
Author(s):  
Jan Kovanda
Keyword(s):  
System Analysis ◽  
Material System ◽  
Material Flows

scholarly journals Comparative analysis of a novel low concentration dual photovoltaic/phase change material system with a non-concentrator photovoltaic system

2019 ◽  
pp. 468-468
Author(s):  
Jawad Sarwar ◽  
Arshmah Hasnain ◽  
Ahmed Abbas ◽  
Konstantinos Kakosimos
Keyword(s):  
Phase Change ◽  
Flat Plate ◽  
Phase Change Material ◽  
System Analysis ◽  
Photovoltaic Cell ◽  
Photovoltaic System ◽  
Material System ◽  
To Receive ◽  
Change Material ◽  
Plate System

In this work, a novel design of a concentrated photovoltaic system with thermal management using phase change material is analyzed. The novelty lies in utilizing two mono-facial PV cells, installing one on upper side of the receiver to receive non-concentrated sunlight and installing another photovoltaic cell on bottom side to receive concentrated sunlight. An RT47 (melting range of 41-48?C) phase change material enclosed in an Aluminum containment regulates the temperature of the system. Parabolic trough concentrator is used to focus sunlight on the bottom photovoltaic cell with a concentration ratio of 25. A finite volume based coupled thermal, electrical and optical model is developed and the system is analyzed for environmental conditions of Doha, Qatar. Temperature regulation and electrical power output of upper photovoltaic cell and bottom concentrated photovoltaic cell of proposed design are compared to a conventional flat plate system. Analysis is made for one day of each month of a year. It is found that the proposed design maintains the temperature below 85?C for all months of a year. The performance of the proposed system is comparable to the conventional flat plate system and excels it with power production in the range of -4.7% and +21.7%.

scholarly journals A Methodological Integrated Approach to Analyse Climate Change Effects in Agri-Food Sector: The TIMES Water-Energy-Food Module

2020 ◽  
Vol 17 (21) ◽  
pp. 7703
Author(s):  
Maria Maddalena Tortorella ◽  
Senatro Di Leo ◽  
Carmelina Cosmi ◽  
Patrícia Fortes ◽  
Mauro Viccaro ◽  
...  
Keyword(s):  
Climate Change ◽  
System Analysis ◽  
Food System ◽  
Comprehensive Evaluation ◽  
Sustainable Use ◽  
Integrated Approach ◽  
Energy System ◽  
Material System ◽  
Use Of Resources ◽  
The Times

The European Union’s 2030 climate and energy policy and the 2030 Agenda for Sustainable Development underline the commitment to mitigate climate change and reduce its impacts by supporting sustainable use of resources. This commitment has become stricter in light of the ambitious climate neutrality target set by the European Green Deal for 2050. Water, Energy and Food are the key variables of the “Nexus Thinking” which face the sustainability challenge with a multi-sectoral approach. The aim of the paper is to show the methodological path toward the implementation of an integrated modeling platform based on the Nexus approach and consolidated energy system analysis methods to represent the agri-food system in a circular economy perspective (from the use of water, energy, biomass, and land to food production). The final aim is to support decision-making connected to climate change mitigation. The IEA-The Integrated MARKAL-EFOM System (TIMES) model generator was used to build up the Basilicata Water, Energy and Food model (TIMES-WEF model), which allows users a comprehensive evaluation of the impacts of climate change on the Basilicata agri-food system in terms of land use, yields and water availability and a critical comparison of these indicators in different scenarios. The paper focuses on the construction of the model’s Reference Energy and Material System of the TIMES model, which integrates water and agricultural commodities into the energy framework, and on the results obtained through the calibration of the model β version to statistical data on agricultural activities.

Seeded Fault Testing of Military Ground Vehicles as a Pathway to Condition Based Maintenance

2010 ◽  
Author(s):  
Matthew J. Hillegass ◽  
Eric L. Rabeno
Keyword(s):  
System Analysis ◽  
Condition Based Maintenance ◽  
Engine Oil ◽  
Actual Condition ◽  
Material System ◽  
Fault Testing ◽  
Ground Vehicle ◽  
Us Army ◽  
The Us ◽  
Vehicle Systems

The performance of military ground vehicle systems is being degraded due to high operation tempo and exposure to extreme environments while performing in-theater service. To address this issue, the US Army is implementing a policy of Condition Based Maintenance which is supported by the Army Material System Analysis Activity (AMSAA). The vision of this policy is to base the maintenance of systems upon the actual condition of the system and not upon time- or distance-based schedules. This capability will be enabled by the application of usage, diagnostic and prognostic processes executed on a Health and Usage Monitoring System (HUMS) installed on these vehicle systems. A thorough understanding of the ways in which the system condition is degenerated and the ability of the HUMS to detect, identify, and communicate all conditions that require maintenance in a timely manner are key requirements of these processes. Seeded Fault Testing is the critical means of fulfilling these requirements. A joint Seeded Fault Testing project between AMSAA and the US Army Aberdeen Test Center (ATC) has been initiated to gain a thorough understanding of ground vehicle system condition degeneration and HUMS implementation of products and processes that can accurately identify and communicate it. A military vehicle underwent exhaustive testing in support of this project. The vehicle was subjected to specific use scenarios while carefully controlled faults are induced in engine, transmission, and other key mechanical subsystems that would degrade vehicle performance and degenerate system condition. The vehicle’s induced faults included lowered coolant levels to simulate leakage, restriction of air flow across radiators and filters to simulate dust and debris accumulation, and lowered transmission and engine oil levels to simulate leakage and usage. The objective of this project was to use the results from the seeded fault tests to establish critical thresholds, trends, and patterns that will be the basis of the creation and implementation of real-time HUMS-based algorithms that predict faults, warn operators and maintainers of imminent failures, and provide a sound foundation for Condition Based Maintenance.

Ion thinning of integrated circuit transverse specimens for transmission electron microscopy

1992 ◽  
Vol 50 (2) ◽  
pp. 1426-1427
Author(s):  
F. Shaapur
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Integrated Circuit ◽  
Substrate Surface ◽  
Homogeneous Material ◽  
Material System ◽  
Ion Milling ◽  
Cross Sectional ◽  
Transmission Electron ◽  
Motion Profile

Non-uniform ion-thinning of heterogenous material structures has constituted a fundamental difficulty in preparation of specimens for transmission electron microscopy (TEM). A variety of corrective procedures have been developed and reported for reducing or eliminating the effect. Some of these techniques are applicable to any non-homogeneous material system and others only to unidirectionalfy heterogeneous samples. Recently, a procedure of the latter type has been developed which is mainly based on a new motion profile for the specimen rotation during ion-milling. This motion profile consists of reversing partial revolutions (RPR) within a fixed sector which is centered around a direction perpendicular to the specimen heterogeneity axis. The ion-milling results obtained through this technique, as studied on a number of thin film cross-sectional TEM (XTEM) specimens, have proved to be superior to those produced via other procedures.XTEM specimens from integrated circuit (IC) devices essentially form a complex unidirectional nonhomogeneous structure. The presence of a variety of mostly lateral features at different levels along the substrate surface (consisting of conductors, semiconductors, and insulators) generally cause non-uniform results if ion-thinned conventionally.

Cross-sectional TEM specimen preparation from magneto-optical disk by ultramicrotomy

1993 ◽  
Vol 51 ◽  
pp. 236-237
Author(s):  
F. Shaapur ◽  
M.J. Kim ◽  
Seh Kwang Lee ◽  
Soon Gwang Kim
Keyword(s):  
System Development ◽  
Thin Foil ◽  
Specimen Preparation ◽  
Material System ◽  
Cross Sectional ◽  
Protective Layers ◽  
New Material ◽  
Diamond Saw ◽  
Original Production ◽  
Thick Medium

TEM characterization and microanalysis of the recording media is crucial and complementary to new material system development as well as quality control applications. Due to the type of material generally used for supporting the medium, i.e., a polymer, conventional macro- and microthinning procedures for thin foil preparation are not applicable. Ultramicrotorny (UM) is a viable option and has been employed in previous similar studies. In this work UM has been used for preparation of XTEM samples from a magneto-optical (MO) recording medium in its original production format.The as-received material system consisted of a 4-layer, 2100 Å thick medium including a 300 Å TbFeCo layer enveloped by silicon nitride protective layers supported on a 1.2 mm thick × 135 mm (5.25 in.) diameter polycarbonate disk. Recording tracks had an approximate pitch of 1.6 μm separated by 800 Å deep peripheral grooves. Using a Buehler Isomet low-speed diamond saw, 1 mm wide and 20 mm long strips were cut out of the disk along the recording tracks.

CBED study of low-temperature InP grown by gas source MBE

1993 ◽  
Vol 51 ◽  
pp. 810-811
Author(s):  
R. Rajesh ◽  
M.J. Kim ◽  
J.S. Bow ◽  
R.W. Carpenter ◽  
G.N. Maracas
Keyword(s):  
Low Temperature ◽  
Second Phase ◽  
Material System ◽  
Ion Milling ◽  
Electrical Measurements ◽  
Gas Source ◽  
Structural And Electrical Properties ◽  
The One ◽  
Lt Inp ◽  
Gas Source Mbe

In our previous work on MBE grown low temperature (LT) InP, attempts had been made to understand the relationships between the structural and electrical properties of this material system. Electrical measurements had established an enhancement of the resistivity of the phosphorus-rich LT InP layers with annealing under a P2 flux, which was directly correlated with the presence of second-phase particles. Further investigations, however, have revealed the presence of two fundamentally different types of precipitates. The first type are the surface particles, essentially an artefact of argon ion milling and containing mostly pure indium. The second type and the one more important to the study are the dense precipitates in the bulk of the annealed layers. These are phosphorus-rich and are believed to contribute to the improvement in the resistivity of the material.The observation of metallic indium islands solely in the annealed LT layers warranted further study in order to better understand the exact reasons for their formation.

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