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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,315 records · Page 73
All sourcesNASA NTRSDOE OSTI
DOE OSTI2013

Synthesis, magnetic and dielectric characterization of nanocrystalline solid solutions of In{sub 2−x}Ni{sub x}O{sub 3} (x = 0.05, 0.10 and 0.15)

Graphical abstract: Monophasic and crystalline In{sub 2−x}Ni{sub x}O{sub 3} nanoparticles of size 8–15 nm have been synthesized solvothermally and showed red shift in energy band gap which decreases on increasing Ni{sup 2+} concentration in In{sub 2}O{sub 3} host lattice. - Highlights: • Monophasic Ni-doped In{sub 2}O{sub 3} nanoparticles by solvothermal method for first time. • Plausible reaction mechanism using thermogravimetric analysis. • High surface area with small particle size obtained. • Solid solutions exhibit paramagnetism with very weak antiferromagnetic interactions. - Abstract: In{sub 2−x}Ni{sub x}O{sub 3} (x = 0.05, 0.10 and 0.15) nanoparticles were successfully synthesized by solvothermal method by the thermal decomposition of oxalate precursor at 450 °C for the first time. X-ray diffraction studies showed the formation of highly crystalline and monophasic cubic structure of In{sub 2}O{sub 3} which is attributed to the formation of solid solution. These nanoparticles show good optical transmittance in the visible region. Optical measurements showed an energy band gap which decreases with increasing Ni concentration. The grain size decreases from 15 nm to 8 nm and surface area increases from 90 to 254 m{sup 2} g{sup −1} on increasing the Ni concentration. High dielectric constant and dielectric loss has been obtained which indicates the conducting nature of these solid solutions. Magnetic measurements showed that the samples are strong paramagnetic in nature with very weak antiferromagnetic interactions. No evidence of ferromagnetism is observed for these solid solutions at room temperature.

36 MATERIALS SCIENCE↗
DOE OSTI2013

Structure and magnetic interactions in the solid solution Ba{sub 3−x}Sr{sub x}Cr{sub 2}O{sub 8}

Highlights: • We describe for the first time the preparation of single- and polycrystalline members of the solid solution Ba{sub 3−x}Sr{sub x}Cr{sub 2}O{sub 8}. • We report on the structural changes in the solid solution at room temperature depending on the stoichiometry. • We describe the peculiar change of the magnetic behavior in the solid solution with the stoichiometry. - Abstract: Solid solutions of the magnetic insulators Ba{sub 3}Cr{sub 2}O{sub 8} and Sr{sub 3}Cr{sub 2}O{sub 8} (Ba{sub 3−x}Sr{sub x}Cr{sub 2}O{sub 8}) have been prepared in polycrystalline form for the first time. Single crystalline material was obtained using a mirror image floating zone technique. X-ray diffraction data taken at room temperature indicate that the space group of Ba{sub 3−x}Sr{sub x}Cr{sub 2}O{sub 8} remains unchanged for all values of x, while the cell parameters depend on the chemical composition, as expected. Magnetization data, measured from 300 K down to 2 K, suggest that the interaction constant J{sub d} within the Cr{sup 5+} dimers varies in a peculiar way as a function of x, starting at J{sub d} = 25 K for x = 0, then first slightly dropping to J{sub d} = 18 K for x ≈ 0.75, before reaching J{sub d} = 62 K for x = 3.

36 MATERIALS SCIENCE↗
DOE OSTI2014

Synthesis of luminescent nanocrystals and solid solutions in the YNbO{sub 4}–EuNbO{sub 4} system via hydrothermal route

Highlights: • Nanocrystals: YNbO{sub 4}:Eu{sup 3+} were directly formed under hydrothermal conditions at 240 °C. • The nanocrystals (10–20 nm) were luminescent and had ellipsoidal morphology. • The complete solid solutions in the YNbO{sub 4}–EuNbO{sub 4} system were also directly formed. • The PL intensity and R/O intensity ratio changed depending on heating temperature. - Abstract: Luminescent nanocrystals having distinctive ellipsoidal morphology and the complete solid solution of monoclinic phase in the YNbO{sub 4}–EuNbO{sub 4} system were hydrothermally formed under weakly basic conditions at 180–240 °C for 5 h. The excitation spectra of the Y{sub 1−x}Eu{sub x}NbO{sub 4} nanocrystals, which consisted of the charge transfer (CT) band around 240–270 nm due to [NbO{sub 4}]{sup 3−}–Eu{sup 3+} interaction and several sharp bands corresponding to the f–f transitions of Eu{sup 3+}, e.g. the most intense absorption band at 395 nm ({sup 7}F{sub 0}→{sup 5}L{sub 6}), showed that the compounds could be excited by both ultraviolet and visible light. A dominant red emission at 610 nm and a weak orange emission at 590 nm assigned to {sup 5}D{sub 0}→{sup 7}F{sub 2} and {sup 5}D{sub 0}→{sup 7}F{sub 1} transitions of Eu{sup 3+}, respectively were observed in the as-prepared nanocrystals containing europium under excitation at 395 nm. The heat treatment at temperatures more than 1000 °C in air was effective for the improvement in the photoluminescence intensity of the as-prepared solid solutions. By the enhancement in the crystallinity and crystallite growth of the monoclinic phase through heat treatment at 1300 °C in air, the luminescence intensity of the as-prepared solid solution, Y{sub 0.75}Eu{sub 0.25}NbO{sub 4} (x = 0.25), which showed the most significant photoluminescence, became more than 5 times as strong as that before the heat treatment.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Zn{sub 1−x}Co{sub x}WO{sub 4} (0 ≤ x ≤ 1) full range solid solution: Structure, optical properties, and magnetism

Graphical abstract: The continuous modulation on crystal structure and band gap is achieved in the Zn{sub 1−x}Co{sub x}WO{sub 4} (0 ≤ x ≤ 1) full range solid solution. - Highlights: • Zn{sub 1−x}Co{sub x}WO{sub 4} (0 ≤ x ≤ 1) solid solution was synthesized by a hydrothermal method. • They all present a single-phase in the wolframite structure with space group P2/c. • The continuous tenability in band gap was achieved in Zn{sub 1−x}Co{sub x}WO{sub 4} (0 ≤ x ≤ 1). • CoWO{sub 4} and Zn{sub 0.5}Co{sub 0.5}WO{sub 4} are antiferromagnetic and paramagnetic, respectively. - Abstract: A novel full-range solid-solution Zn{sub 1−x}Co{sub x}WO{sub 4} (0 ≤ x ≤ 1) was successfully developed via a facile one-pot hydrothermal route. The phase structure and microstructure were characterized by X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectra and scanning electron microscopy (SEM). The Zn{sub 1−x}Co{sub x}WO{sub 4} solid solution possesses similar wolframite crystal structure with the same space group P2/c. Diffuse reflection spectroscopy (DRS) measurements on Zn{sub 1−x}Co{sub x}WO{sub 4} (0 ≤ x ≤ 1) demonstrated that the optical band gap can be continuously tuned from 3.56 eV to 2.61 eV for direct transition and 1.87 eV for indirect transition, respectively, with increasing x from 0 to 1. Magnetic susceptibility measurements reveal that CoWO{sub 4} has an antiferromagnetic transition at T{sub N} = 42 K, whereas Zn{sub 0.5}Co{sub 0.5}WO{sub 4} exhibits paramagnetic behavior. Moreover, CoWO{sub 4} and Zn{sub 0.5}Co{sub 0.5}WO{sub 4} obey the Curie–Weiss law from 200 k down to 50 K, and their effective magnetic moments were determined.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Solid-state synthesis of Li{sub 4}Ti{sub 5}O{sub 12} whiskers from TiO{sub 2}-B

Highlights: • The Li{sub 4}Ti{sub 5}O{sub 12} whiskers were synthesized from TiO{sub 2}-B whiskers via a solid state reaction. • The TiO{sub 2}-B crystal structure for lithium diffusion is easier than anatase. • The separated diffusion and reaction process is crucial for the solid-state syntheses of Li{sub 4}Ti{sub 5}O{sub 12} whiskers. - Abstract: In this work, Li{sub 4}Ti{sub 5}O{sub 12} (LTO) was synthesized from the precursors of TiO{sub 2}-B and anatase whiskers, respectively. The synthesized LTO whiskers from TiO{sub 2}-B whiskers via a solid state reaction at 650 °C have a high degree of crystallinity with an average diameter of 300 nm. However, when anatase whiskers were used as the precursor, only particle morphology LTO was produced at 750 °C. The further analysis of the precursors, the intermediate products and the final products reveal that the crystal structure of the anatase hinders the diffusion of lithium, leading to a typical reaction–diffusion process. Under this condition, only particle morphology LTO can be produced. However, the crystal structure of the TiO{sub 2}-B is easy for lithium diffusion and the process is performed in two separated steps (i.e., diffusion and reaction), which makes it possible to decrease the solid-state reaction temperature down to 650 °C and then maintain the morphologies of whiskers.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Structural ordering at solid-liquid interfaces in Al-Sm system: A molecular-dynamics study

The structural ordering at solid-liquid interfaces far from equilibrium is studied with molecular dynamics simulations for the Al-Sm system. Using the van-Hove self-correlation function as the criterion to identify attachment/detachment events that occur at the interface, we are able to determine the time-dependent interface position, and characterize the detailed interfacial structure ordering surrounding the attached atoms. For the interface between an undercooled Al90Sm10 liquid and a metastable cubic structure, the solid induces the crystalline order of the cubic phase in the liquid layers, promoting the continuous growth of the crystal phase. When the same liquid is put in contact with f.c.c. Al, Sm from the liquid can still attach to the solid interface despite its insolubility in the Al lattice. Non-f.c.c. order is revealed surrounding the attached Sm atoms. Lastly, we show that the local structure ordering at interface is highly correlated to solid packing and liquid ordering.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Optimizing the impacts of solid additives on the operational stability and processing reliability of organic solar cells

Previous reports have revealed that by leveraging solid additives, organic solar cells (OSCs) can surpass the device’s performance beyond the intrinsic limitations of host photoactive molecules, a remarkable advancement. However, the impacts of more complex interactions introduced by solid additives are not yet well understood. Herein, optimizing the fabrication process based on the traditional efficiency-guided approach fails to represent the ideal and most practical devices. In particular, achieving superior operational stability while minimizing the device performance scattering was found to require processing solvent evaporation to be synchronized with the volatility of the chosen solid additive. However, this may be challenging since most organic photoactive materials display excellent efficiencies only with selected solvents. Accordingly, this work also demonstrates the potential of dual and complementary solvents selection, consisting of low boiling point (primary) and high boiling point (secondary). This strategy allows for the suppression of any potential trade-offs in efficiency. Meanwhile, the operational stability and precision of device performance are substantially enhanced. Additionally, solid additives have demonstrated that the singlet exciton dissociation rate does not limit the free charge generation yield. Finally, these findings are expected to reformulate OSC device fabrication strategies towards more practical devices.

36 MATERIALS SCIENCE↗
DOE OSTI2021

On the quality of tape-cast thin films of sulfide electrolytes for solid-state batteries

All-solid-state lithium batteries (ASSLBs) have the potential to increase energy density, improve safety, and allow for lower manufacturing costs compared to conventional, liquid-based Li-ion batteries. The thickness of solid electrolyte (SE) layer dictates the cell-level energy density and it is desirable to make the SE layer as thin as possible while maintaining uniformity and defect-free. Manufacturing a high- quality, thin sulfide SE layer at large-scale, however, is challenging. Previous studies have addressed the compatibility of materials used for manufacturing thin sulfide SE films, paving the way for further investigation of processing conditions and film quality. Here we report a strong correlation between the solid loading of dispersions and the quality of tape-casted thin sulfide SE films. We also demonstrate a method for quantifying the quality of thin SE films by observing both pin-hole defects and larger heterogeneous agglomerations of particles in the films. Our thin sulfide SE films containing ~5 wt% binder are defect-free and show similar ionic conductivity compared to a cold-pressed, binder-free, thick SE pellet, resulting in an ~11X reduction of area specific resistance. Here, this work on the solid loading of the dispersion used in a scalable tape casting process provides insight for manufacturing high-quality, thin sulfide SE films and to increase the cell-level energy density of ASSLB.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Current Status and Future Directions of All-Solid-State Batteries with Lithium Metal Anodes, Sulfide Electrolytes, and Layered Ternary Oxide Cathodes

All-solid-state batteries (ASSBs) offer great promise as a next-generation energy storage technology with higher energy density, wider operating temperature range, and improved safety for electric vehicles. ASSBs employing lithium metal anodes (Li), sulfide-based solid-state electrolytes (SSE), and Ni-rich layered transition metal oxide cathodes (LiMO 2 , M = Ni, Mn, Co, Al) are particularly promising due to its superior electrochemical performance compared to other solid-electrolyte systems. However, the battery cycle life at high cathode mass loading and high current is still limited because the failure mechanism is not fully understood. Lithium dendrite growth at the anode or inside a solid electrolyte still represents as a serious risk of cell failure. Interfacial resistance increases attributed to electrolyte decomposition and interfacial void formation at both cathode–electrolyte and anode–electrolyte interfaces lead to gradual capacity fading. In this Review, we present the fundamental challenges and recent scientific understandings of each component in ASSBs. The novel diagnostic tools for these components, especially the interfaces buried under the surface that are often hard for characterization are mainly examined. Lastly, we offer a perspective for future research directions. We hope this Review will provide a timely snapshot of state-of-the-art research progress in ASSBs to accelerate the development of ASSBs.

25 ENERGY STORAGE↗
DOE OSTI2022

Stable all-solid-state sodium-sulfur batteries for low-temperature operation enabled by sodium alloy anode and confined sulfur cathode

All-solid-state sodium-sulfur (Na-S) batteries are promising for stationary energy storage devices because of their low operating temperatures (less than 100 °C), improved safety, and low-cost fabrication. Using Na alloy instead of Na metal as an anode in Na-S batteries can prevent dendrite growth and improve interfacial stability between the anode and solid electrolytes to achieve long-cycling stability. A high-sulfur content cathode possessing high sulfur utilization is also important to enable an energy-dense Na-S battery. In this work, we studied Na-Sb and Na- Sn alloy anodes and demonstrated the superiority of Na 3 Sb alloy undergoing a stable Na alloying/dealloying process at 0.04 mA cm -2 for over 500 hours. Combining the optimized Na3Sb alloy anode with sulfur-carbon composites prepared by the vapor deposition approach, the full cell shows a high sulfur specific capacity and improved rate performance. Moreover, the all-solid-state Na alloy-S battery can deliver a high initial discharge specific capacity of 1377 mAh g -1 and maintain good capacity retention of 70 % after 180 cycles at 60 °C. Further, post-cycle characterizations show that both the anode and cathode perform a reversible discharge/charge process after the 1st cycle, and the cathode undergoes significantly rearranged distributions of carbon and solid-state electrolytes after 180 cycles due to severe volume change induced by repeated sodiation/desodiation process.

25 ENERGY STORAGE↗
DOE OSTI2023

Accelerated test protocols to predict service life and durability of solid oxide fuel cells

Reliable accelerated test protocols are needed for solid oxide fuel cell research to facilitate rapid learning on key durability issues, identify potential modes of failure expeditiously, and eventually predict the calendar lifetime of an electrochemical cell. In this work, solid oxide fuel cells operated at a constant current density were compared to cells undergoing accelerated measurements, which are composed of intermittent current injection to the cell. A general accelerated test profile was developed by cycling a solid oxide fuel cell from open circuit to a predetermined operating current density that is the same as the current density during a steady-state operation, to accelerate the local redox environment. The following parameters were studied: current density, operation temperature, moist level, sintering temperature, cycling current, cycling frequency, and operation time. Up to 1,320,000 cycles were generated in this work. The cell degradation was accelerated by nearly 10 times, suggesting the feasibility of using this protocol for acceleration test to predict life performance and durability of solid oxide fuel cells.

08 HYDROGEN↗
DOE OSTI2020

Numerical simulations of onset and growth of Rayleigh–Taylor instability involving solids in converging geometry

Numerical simulation of Rayleigh–Taylor instabilities involving solids has been carried out in a spherically converging geometry. A solid shell is driven toward the center by high-pressure gas outside. Low-pressure gas inside the shell is then compressed, causing the solid shell to slow down and eventually bounce back. Here, simulation results show the absence of the onset condition unlike in the planar geometry equivalent. Results also show that disturbance growth seems to be strongly associated with the deformation direction instead of the acceleration direction. For example, when the interface is compressed in the cross-stream direction, the disturbance at the gas–solid interface grows even under the Rayleigh–Taylor stable situation.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2017

Crosslinked perfluoropolyether solid electrolytes for lithium ion transport

Perfluoropolyethers (PFPE) are commercially available non-flammable short chain polymeric liquids. End-functionalized PFPE chains solvate lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt and these mixtures can be used as electrolytes for lithium (Li) batteries. Here we synthesize and characterize a new class of solid PFPE electrolytes. The electrolytes are made by either thermal or UV crosslinking PFPE chains with urethane methacrylate end-groups. For the synthesis of thermally crosslinked electrolytes, polyhedral oligomeric silsesquioxane (POSS) with organic acrylopropyl groups was used as crosslinker agent, while for UV cured electrolytes a photoinitiatior was used. We present thermal, morphological, and electrical data of the solid electrolytes. We compare these properties with those of the two parent liquids (PFPE with urethane methacrylate end-groups and POSS with acrylopropyl groups) mixed with LiTFSI. The solubility limit of LiTFSI in the PFPE-based solids is higher than that in the liquids. The conductivity data are analyzed using the Vogel–Tamman–Fulcher equation. In conclusion, the concentration of effective charge carriers is a strong function of the nature of the solvent (solid versus liquid) whereas the activation energy is neither a strong function of the nature of the solvent nor salt concentration.

25 ENERGY STORAGE↗
DOE OSTI2012

Process and technological aspects of municipal solid waste gasification. A review

Highlights: Black-Right-Pointing-Pointer Critical assessment of the main commercially available MSW gasifiers. Black-Right-Pointing-Pointer Detailed discussion of the basic features of gasification process. Black-Right-Pointing-Pointer Description of configurations of gasification-based waste-to-energy units. Black-Right-Pointing-Pointer Environmental performance analysis, on the basis of independent sources data. - Abstract: The paper proposes a critical assessment of municipal solid waste gasification today, starting from basic aspects of the process (process types and steps, operating and performance parameters) and arriving to a comparative analysis of the reactors (fixed bed, fluidized bed, entrained bed, vertical shaft, moving grate furnace, rotary kiln, plasma reactor) as well as of the possible plant configurations (heat gasifier and power gasifier) and the environmental performances of the main commercially available gasifiers for municipal solid wastes. The analysis indicates that gasification is a technically viable option for the solid waste conversion, including residual waste from separate collection of municipal solid waste. It is able to meet existing emission limits and can have a remarkable effect on reduction of landfill disposal option.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2012

Determinants of sustainability in solid waste management - The Gianyar Waste Recovery Project in Indonesia

Highlights: Black-Right-Pointing-Pointer Our assessment tool helps evaluate success factors in solid waste projects. Black-Right-Pointing-Pointer Success of the composting plant in Indonesia is linked to its community integration. Black-Right-Pointing-Pointer Appropriate technology is not a main determining success factor for sustainability. Black-Right-Pointing-Pointer Structured assessment of 'best practices' can enhance replication in other cities. - Abstract: According to most experts, integrated and sustainable solid waste management should not only be given top priority, but must go beyond technical aspects to include various key elements of sustainability to ensure success of any solid waste project. Aside from project sustainable impacts, the overall enabling environment is the key feature determining performance and success of an integrated and affordable solid waste system. This paper describes a project-specific approach to assess typical success or failure factors. A questionnaire-based assessment method covers issues of: (i) social mobilisation and acceptance (social element), (ii) stakeholder, legal and institutional arrangements comprising roles, responsibilities and management functions (institutional element); (iii) financial and operational requirements, as well as cost recovery mechanisms (economic element). The Gianyar Waste Recovery Project in Bali, Indonesia was analysed using this integrated assessment method. The results clearly identified chief characteristics, key factors to consider when planning country wide replication but also major barriers and obstacles which must be overcome to ensure project sustainability. The Gianyar project consists of a composting unit processing 60 tons of municipal waste per day from 500,000 inhabitants, including manual waste segregation and subsequent composting of the biodegradable organic fraction.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2013

Microbial diversity and dynamics during methane production from municipal solid waste

Highlights: ► Similar bacterial communities developed following different start-up operation. ► Total methanogens in leachate during the decelerated methane phase reflected overall methane yield. ► Created correlations between methanogens, methane yield, and available substrate. ► Predominant bacteria identified with syntrophic polysaccharide degraders. ► Hydrogenotrophic methanogens were dominant in the methane generation process. - Abstract: The objectives of this study were to characterize development of bacterial and archaeal populations during biodegradation of municipal solid waste (MSW) and to link specific methanogens to methane generation. Experiments were conducted in three 0.61-m-diameter by 0.90-m-tall laboratory reactors to simulate MSW bioreactor landfills. Pyrosequencing of 16S rRNA genes was used to characterize microbial communities in both leachate and solid waste. Microbial assemblages in effluent leachate were similar between reactors during peak methane generation. Specific groups within the Bacteroidetes and Thermatogae phyla were present in all samples and were particularly abundant during peak methane generation. Microbial communities were not similar in leachate and solid fractions assayed at the end of reactor operation; solid waste contained a more abundant bacterial community of cellulose-degrading organisms (e.g., Firmicutes). Specific methanogen populations were assessed using quantitative polymerase chain reaction. Methanomicrobiales, Methanosarcinaceae, and Methanobacteriales were the predominant methanogens in all reactors, with Methanomicrobiales consistently the most abundant. Methanogen growth phases coincided with accelerated methane production, and cumulative methane yield increased with increasing total methanogen abundance. The difference in methanogen populations and corresponding methane yield is attributed to different initial cellulose and hemicellulose contents of the MSW. Higher initial cellulose and hemicellulose contents supported growth of larger methanogen populations that resulted in higher methane yield.

09 BIOMASS FUELS↗
DOE OSTI2013

Decision support models for solid waste management: Review and game-theoretic approaches

Highlights: ► The mainly used decision support frameworks for solid waste management are reviewed. ► The LCA, CBA and MCDM models are presented and their strengths, weaknesses, similarities and possible combinations are analyzed. ► The game-theoretic approach in a solid waste management context is presented. ► The waste management bargaining game is introduced as a specific decision support framework. ► Cooperative and non-cooperative game-theoretic approaches to decision support for solid waste management are discussed. - Abstract: This paper surveys decision support models that are commonly used in the solid waste management area. Most models are mainly developed within three decision support frameworks, which are the life-cycle assessment, the cost–benefit analysis and the multi-criteria decision-making. These frameworks are reviewed and their strengths and weaknesses as well as their critical issues are analyzed, while their possible combinations and extensions are also discussed. Furthermore, the paper presents how cooperative and non-cooperative game-theoretic approaches can be used for the purpose of modeling and analyzing decision-making in situations with multiple stakeholders. Specifically, since a waste management model is sustainable when considering not only environmental and economic but also social aspects, the waste management bargaining game is introduced as a specific decision support framework in which future models can be developed.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2014

Solid waste bin detection and classification using Dynamic Time Warping and MLP classifier

Highlights: • Solid waste bin level detection using Dynamic Time Warping (DTW). • Gabor wavelet filter is used to extract the solid waste image features. • Multi-Layer Perceptron classifier network is used for bin image classification. • The classification performance evaluated by ROC curve analysis. - Abstract: The increasing requirement for Solid Waste Management (SWM) has become a significant challenge for municipal authorities. A number of integrated systems and methods have introduced to overcome this challenge. Many researchers have aimed to develop an ideal SWM system, including approaches involving software-based routing, Geographic Information Systems (GIS), Radio-frequency Identification (RFID), or sensor intelligent bins. Image processing solutions for the Solid Waste (SW) collection have also been developed; however, during capturing the bin image, it is challenging to position the camera for getting a bin area centralized image. As yet, there is no ideal system which can correctly estimate the amount of SW. This paper briefly discusses an efficient image processing solution to overcome these problems. Dynamic Time Warping (DTW) was used for detecting and cropping the bin area and Gabor wavelet (GW) was introduced for feature extraction of the waste bin image. Image features were used to train the classifier. A Multi-Layer Perceptron (MLP) classifier was used to classify the waste bin level and estimate the amount of waste inside the bin. The area under the Receiver Operating Characteristic (ROC) curves was used to statistically evaluate classifier performance. The results of this developed system are comparable to previous image processing based system. The system demonstration using DTW with GW for feature extraction and an MLP classifier led to promising results with respect to the accuracy of waste level estimation (98.50%). The application can be used to optimize the routing of waste collection based on the estimated bin level.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗