WorldWideScience

Sample records for plastic providing lightweight

  1. Reuse of thermosetting plastic waste for lightweight concrete.

    Science.gov (United States)

    Panyakapo, Phaiboon; Panyakapo, Mallika

    2008-01-01

    This paper presents the utilization of thermosetting plastic as an admixture in the mix proportion of lightweight concrete. Since this type of plastic cannot be melted in the recycling process, its waste is expected to be more valuable by using as an admixture for the production of non-structural lightweight concrete. Experimental tests for the variation of mix proportion were carried out to determine the suitable proportion to achieve the required properties of lightweight concrete, which are: low dry density and acceptable compressive strength. The mix design in this research is the proportion of plastic, sand, water-cement ratio, aluminum powder, and lignite fly ash. The experimental results show that the plastic not only leads to a low dry density concrete, but also a low strength. It was found that the ratio of cement, sand, fly ash, and plastic equal to 1.0:0.8:0.3:0.9 is an appropriate mix proportion. The results of compressive strength and dry density are 4.14N/mm2 and 1395 kg/m3, respectively. This type of concrete meets most of the requirements for non-load-bearing lightweight concrete according to ASTM C129 Type II standard.

  2. Lightweight Inexpensive Ozone Lidar Telescope Using a Plastic Fresnel Lens

    Science.gov (United States)

    DeYoung, Russell J.; Notari, Anthony; Carrion, William; Pliutau, Denis

    2014-01-01

    An inexpensive lightweight ozone lidar telescope was designed, constructed and operated during an ozone lidar field campaign. This report summarizes the design parameters and performance of the plastic Fresnel lens telescope and shows the ozone lidar performance compared to Zemax calculations.

  3. Lightweight Brick by Carbon Ash from The Mixed Plastic Waste Treatment Plant

    OpenAIRE

    Chen Kuo-Wei

    2016-01-01

    This study was designed to investigate the mixed plastic waste from the production of light carbon ash bricks performance. The mixed waste plastic pyrolysis process generated waste - Carbon ash. After extrusion, a Lightweight brick was made by carbon ash, additive and Cement mortar. In general, the set compressive strength and insulation effect of lightweight bricks with carbon ash proportion for significant impact. The set water absorption and thermal conductivity of lightweight bricks with ...

  4. Lightweight Brick by Carbon Ash from The Mixed Plastic Waste Treatment Plant

    Directory of Open Access Journals (Sweden)

    Chen Kuo-Wei

    2016-01-01

    Full Text Available This study was designed to investigate the mixed plastic waste from the production of light carbon ash bricks performance. The mixed waste plastic pyrolysis process generated waste - Carbon ash. After extrusion, a Lightweight brick was made by carbon ash, additive and Cement mortar. In general, the set compressive strength and insulation effect of lightweight bricks with carbon ash proportion for significant impact. The set water absorption and thermal conductivity of lightweight bricks with carbon ash proportion for significant impact. The set density of lightweight brick ameliorates with M3824 additive and CM3 cement mortar for significant impact. Under conditions of technology and economic, the results of this study as reference for market-oriented marketing and commercialization of production.

  5. UTILIZING WASTE PLASTIC POLYPROPYLENE AND POLYETHYLENE TEREPHTHALATE AS ALTERNATIVE AGGREGATES TO PRODUCE LIGHTWEIGHT CONCRETE: A REVIEW

    OpenAIRE

    IBRAHIM H. ALFAHDAWI; S. A. OSMAN; R. HAMID; ABDULKADER ISMAIL AL-HADITHI

    2016-01-01

    In recent times, there is an increasing need for the fabrication of mortar and concrete that can be characterised as sustainable and environmentally friendly. Ideally, this concrete should be inexpensive, lightweight, and outstanding in terms of its physical and mechanical specifications. Plastic materials have increasingly been used in the fabrication of different types of concrete admixtures and mortar constituents. These plastic materials take the form of fillers or shredded fibres derived...

  6. Plastic Muscles TM as lightweight, low voltage actuators and sensors

    Science.gov (United States)

    Bennett, Matthew; Leo, Donald; Duncan, Andrew

    2008-03-01

    Using proprietary technology, Discover Technologies has developed ionomeric polymer transducers that are capable of long-term operation in air. These "Plastic Muscle TM" transducers are useful as soft distributed actuators and sensors and have a wide range of applications in the aerospace, robotics, automotive, electronics, and biomedical industries. Discover Technologies is developing novel fabrication methods that allow the Plastic Muscles TM to be manufactured on a commercial scale. The Plastic Muscle TM transducers are capable of generating more than 0.5% bending strain at a peak strain rate of over 0.1 %/s with a 3 V input. Because the Plastic Muscles TM use an ionic liquid as a replacement solvent for water, they are able to operate in air for long periods of time. Also, the Plastic Muscles TM do not exhibit the characteristic "back relaxation" phenomenon that is common in water-swollen devices. The elastic modulus of the Plastic Muscle TM transducers is estimated to be 200 MPa and the maximum generated stress is estimated to be 1 MPa. Based on these values, the maximum blocked force at the tip of a 6 mm wide, 35 mm long actuator is estimated to be 19 mN. Modeling of the step response with an exponential series reveals nonlinearity in the transducers' behavior.

  7. UTILIZING WASTE PLASTIC POLYPROPYLENE AND POLYETHYLENE TEREPHTHALATE AS ALTERNATIVE AGGREGATES TO PRODUCE LIGHTWEIGHT CONCRETE: A REVIEW

    Directory of Open Access Journals (Sweden)

    IBRAHIM H. ALFAHDAWI

    2016-08-01

    Full Text Available In recent times, there is an increasing need for the fabrication of mortar and concrete that can be characterised as sustainable and environmentally friendly. Ideally, this concrete should be inexpensive, lightweight, and outstanding in terms of its physical and mechanical specifications. Plastic materials have increasingly been used in the fabrication of different types of concrete admixtures and mortar constituents. These plastic materials take the form of fillers or shredded fibres derived from polypropylene and polyethylene terephthalate. The use of plastic materials presents the following benefits: (i enhanced mixture quality and (ii a reduction in the amount of accumulated single-use plastic materials that negatively impact the environment. This work reviews several previous studies on the utilisation and preparations of plastic materials and their effects on the physical and mechanical properties of concrete. Other topics, including hardened concrete, fresh concrete, application, and thermo-physical characteristics, are also elaborated.

  8. An ultra-lightweight design for imperceptible plastic electronics.

    Science.gov (United States)

    Kaltenbrunner, Martin; Sekitani, Tsuyoshi; Reeder, Jonathan; Yokota, Tomoyuki; Kuribara, Kazunori; Tokuhara, Takeyoshi; Drack, Michael; Schwödiauer, Reinhard; Graz, Ingrid; Bauer-Gogonea, Simona; Bauer, Siegfried; Someya, Takao

    2013-07-25

    Electronic devices have advanced from their heavy, bulky origins to become smart, mobile appliances. Nevertheless, they remain rigid, which precludes their intimate integration into everyday life. Flexible, textile and stretchable electronics are emerging research areas and may yield mainstream technologies. Rollable and unbreakable backplanes with amorphous silicon field-effect transistors on steel substrates only 3 μm thick have been demonstrated. On polymer substrates, bending radii of 0.1 mm have been achieved in flexible electronic devices. Concurrently, the need for compliant electronics that can not only be flexed but also conform to three-dimensional shapes has emerged. Approaches include the transfer of ultrathin polyimide layers encapsulating silicon CMOS circuits onto pre-stretched elastomers, the use of conductive elastomers integrated with organic field-effect transistors (OFETs) on polyimide islands, and fabrication of OFETs and gold interconnects on elastic substrates to realize pressure, temperature and optical sensors. Here we present a platform that makes electronics both virtually unbreakable and imperceptible. Fabricated directly on ultrathin (1 μm) polymer foils, our electronic circuits are light (3 g m(-2)) and ultraflexible and conform to their ambient, dynamic environment. Organic transistors with an ultra-dense oxide gate dielectric a few nanometres thick formed at room temperature enable sophisticated large-area electronic foils with unprecedented mechanical and environmental stability: they withstand repeated bending to radii of 5 μm and less, can be crumpled like paper, accommodate stretching up to 230% on prestrained elastomers, and can be operated at high temperatures and in aqueous environments. Because manufacturing costs of organic electronics are potentially low, imperceptible electronic foils may be as common in the future as plastic wrap is today. Applications include matrix-addressed tactile sensor foils for health care and

  9. Novel ferrite–austenite duplex lightweight steel with 77% ductility by transformation induced plasticity and twinning induced plasticity mechanisms

    International Nuclear Information System (INIS)

    Sohn, Seok Su; Choi, Kayoung; Kwak, Jai-Hyun; Kim, Nack J.; Lee, Sunghak

    2014-01-01

    The need for lightweight materials has been an important issue in automotive industries to reduce greenhouse gas emission and to improve fuel efficiency. In addition, automotive steels require an excellent combination of strength and ductility to sustain automotive structures and to achieve complex shapes, but the traditional approach to obtain a reduction in weight from down-gauged steels with high strength has many limitations. Here, we present a new ferrite–austenite duplex lightweight steel containing a low-density element, Al; this steel exhibits tensile elongation up to 77% as well as high tensile strength (734 MPa). The enhanced properties are attributed to the simultaneous formation of deformation-induced martensites and deformation twins and the additional plasticity due to deformation twinning in austenite grains having optimal mechanical stability. The present work gives a promise for automotive applications requiring excellent properties as well as reduced specific weight

  10. Plastic shrinkage of mortars with shrinkage reducing admixture and lightweight aggregates studied by neutron tomography

    Energy Technology Data Exchange (ETDEWEB)

    Wyrzykowski, Mateusz, E-mail: mateusz.wyrzykowski@empa.ch [Empa, Swiss Federal Laboratories for Materials Science and Technology, Concrete and Construction Chemistry Laboratory, Dübendorf (Switzerland); Lodz University of Technology, Department of Building Physics and Building Materials, Lodz (Poland); Trtik, Pavel [Paul Scherrer Institute, Laboratory for Neutron Scattering and Imaging, Villigen (Switzerland); Empa, Swiss Federal Laboratories for Materials Science and Technology, Concrete and Construction Chemistry Laboratory, Dübendorf (Switzerland); Münch, Beat [Empa, Swiss Federal Laboratories for Materials Science and Technology, Concrete and Construction Chemistry Laboratory, Dübendorf (Switzerland); Weiss, Jason [Purdue University, School of Civil Engineering, West Lafayette (United States); Vontobel, Peter [Paul Scherrer Institute, Laboratory for Neutron Scattering and Imaging, Villigen (Switzerland); Lura, Pietro [Empa, Swiss Federal Laboratories for Materials Science and Technology, Concrete and Construction Chemistry Laboratory, Dübendorf (Switzerland); ETH Zurich, Institute for Building Materials (IfB), Zurich (Switzerland)

    2015-07-15

    Water transport in fresh, highly permeable concrete and rapid water evaporation from the concrete surface during the first few hours after placement are the key parameters influencing plastic shrinkage cracking. In this work, neutron tomography was used to determine both the water loss from the concrete surface due to evaporation and the redistribution of fluid that occurs in fresh mortars exposed to external drying. In addition to the reference mortar with a water to cement ratio (w/c) of 0.30, a mortar with the addition of pre-wetted lightweight aggregates (LWA) and a mortar with a shrinkage reducing admixture (SRA) were tested. The addition of SRA reduced the evaporation rate from the mortar at the initial stages of drying and reduced the total water loss. The pre-wetted LWA released a large part of the absorbed water as a consequence of capillary pressure developing in the fresh mortar due to evaporation.

  11. Plastic shrinkage of mortars with shrinkage reducing admixture and lightweight aggregates studied by neutron tomography

    International Nuclear Information System (INIS)

    Wyrzykowski, Mateusz; Trtik, Pavel; Münch, Beat; Weiss, Jason; Vontobel, Peter; Lura, Pietro

    2015-01-01

    Water transport in fresh, highly permeable concrete and rapid water evaporation from the concrete surface during the first few hours after placement are the key parameters influencing plastic shrinkage cracking. In this work, neutron tomography was used to determine both the water loss from the concrete surface due to evaporation and the redistribution of fluid that occurs in fresh mortars exposed to external drying. In addition to the reference mortar with a water to cement ratio (w/c) of 0.30, a mortar with the addition of pre-wetted lightweight aggregates (LWA) and a mortar with a shrinkage reducing admixture (SRA) were tested. The addition of SRA reduced the evaporation rate from the mortar at the initial stages of drying and reduced the total water loss. The pre-wetted LWA released a large part of the absorbed water as a consequence of capillary pressure developing in the fresh mortar due to evaporation

  12. Hybrid-Plus in lightweight construction? Metal-plastic composites; Hybrid-Plus in Struktur-Leichtbauweise? Metall-Kunststoffverbund

    Energy Technology Data Exchange (ETDEWEB)

    Michel, P [Rehau AG und Co., Rehau (Germany)

    2008-07-01

    New dimensions in lightweight structures construction are expected from an advanced technology that produces one hundred percent positively bonded plastic-metal bonds with highly interesting features. The example of a car boot cover is presented to illustrate the technology. (orig.)

  13. Next Generation , Lightweight, Durable Boot Materials to Provide Active & Passive Thermal Protection, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this NASA Phase I SBIR program is to leverage lightweight, durable materials developed by NanoSonic for use within extra vehicular activity (EVA)...

  14. A Lightweight AV System for Providing a Faithful and Spatially Manipulable Visual Hand Representation

    OpenAIRE

    Pusch , Andreas; Martin , Olivier; Coquillart , Sabine

    2011-01-01

    Session: Developing new tools and technologies - Abstracts to be published in a regular issue of the journal Cyberpsychology, Behavior and Social Networking (indexed in MedLine and PsychInfo): http://online.liebertpub.com/loi/CYBER; International audience; This paper introduces the technical foundations of a system designed to embed a lightweight, faithful and spatially manipulable representation of the user's hand into an otherwise virtual world (aka Augmented Virtuality, AV). A highly intui...

  15. Development of lightweight aggregates from stone cutting sludge, plastic wastes and sepiolite rejections for agricultural and environmental purposes.

    Science.gov (United States)

    Moreno-Maroto, José Manuel; González-Corrochano, Beatriz; Alonso-Azcárate, Jacinto; Rodríguez, Luis; Acosta, Anselmo

    2017-09-15

    Three different wastes have been assessed for lightweight aggregate (LWA) manufacturing: granite and marble sludge (COR), sepiolite rejections (SEP) and polyethylene-hexene thermoplastics (P). A preliminary study of the physical and chemical properties of the raw materials was carried out to design proper batches. It was mixed 10% SEP with 90% COR to confer plasticity, and in turn, 0, 2.5, 5 and 10% (w/w) of P was added to check its suitability as a bloating agent. The mixtures were milled, kneaded with water, extruded, shaped into pellets, oven-dried and finally fired at 1100, 1125 and 1150 °C for 4, 8 and 16 min. The main technological properties of the aggregates related to bloating, density, porosity, loss on ignition, water absorption and compressive strength were measured. Scanning Electron Microscopy was used to study the microstructure of some LWAs. 23 out of 29 types of aggregate were lightweight, although neither bloating effect was observed, nor the typical cellular structure comprised of shell and core with relatively large pores was obtained, but a structure consisting of micropores and microchannels. The increase of temperature and time of firing involved a greater sintering, which in turn was translated into higher shrinkage, density and compressive strength values, but less porosity and water absorption. The addition of P did not involve any improvement, indeed it caused a significant decrease in compressive strength. The LWA sintered without P at the minimum time (4 min) and temperature of firing (1100 °C) was selected to assess its water suction capability. The results pointed out that this LWA could be suitable in hydroponics and/or water filtration systems, even better than the commercial LWA Arlita G3. A new and most environment-friendly perspective in LWA industry arises from here, promoting LWA production at relative low temperatures (prior to significant sintering occurs) and using non-plastic silty wastes instead of clays as major

  16. Plastic

    International Nuclear Information System (INIS)

    Jeong Gi Hyeon

    1987-04-01

    This book deals with plastic, which includes introduction for plastic, chemistry of high polymers, polymerization, speciality and structure of a high molecule property of plastic, molding, thermosetting plastic, such as polyethylene, polyether, polyamide and polyvinyl acetyl, thermal plastic like phenolic resins, xylene resins, melamine resin, epoxy resin, alkyd resin and poly urethan resin, new plastic like ionomer and PPS resin, synthetic laminated tape and synthetic wood, mixed materials in plastic, reprocessing of waste plastic, polymer blend, test method for plastic materials and auxiliary materials of plastic.

  17. Ni Nanobuffer Layer Provides Light-Weight CNT/Cu Fibers with Superior Robustness, Conductivity, and Ampacity.

    Science.gov (United States)

    Zou, Jingyun; Liu, Dandan; Zhao, Jingna; Hou, Ligan; Liu, Tong; Zhang, Xiaohua; Zhao, Yonghao; Zhu, Yuntian T; Li, Qingwen

    2018-03-07

    Carbon nanotube (CNT) fiber has not shown its advantage as next-generation light-weight conductor due to the large contact resistance between CNTs, as reflected by its low conductivity and ampacity. Coating CNT fiber with a metal layer like Cu has become an effective solution to this problem. However, the weak CNT-Cu interfacial bonding significantly limits the mechanical and electrical performances. Here, we report that a strong CNT-Cu interface can be formed by introducing a Ni nanobuffer layer before depositing the Cu layer. The Ni nanobuffer layer remarkably promotes the load and heat transfer efficiencies between the CNT fiber and Cu layer and improves the quality of the deposited Cu layer. As a result, the new composite fiber with a 2 μm thick Cu layer can exhibit a superhigh effective strength >800 MPa, electrical conductivity >2 × 10 7 S/m, and ampacity >1 × 10 5 A/cm 2 . The composite fiber can also sustain 10 000 times of bending and continuously work for 100 h at 90% ampacity.

  18. The efficacy of online communication platforms for plastic surgeons providing extended disaster relief.

    Science.gov (United States)

    Fan, Kenneth L; Avashia, Yash J; Dayicioglu, Deniz; DeGennaro, Vincent A; Thaller, Seth R

    2014-04-01

    Immediately after the January 2010 earthquake in Haiti, plastic surgeons provided disaster relief services through the University of Miami Miller School of Medicine for 5 months. To improve surgical care and promote awareness of plastic surgery's role in humanitarian assistance, an online communication platform (OCP) was initiated. An OCP is a Web-based application combining Web blogging, picture uploading, news posting, and private messaging systems into a single platform. The purpose of this study was to analyze the use of OCP during disaster relief. Surgeries performed during the period from January 13 to May 28, 2010, were documented. The OCP was established with 4 priorities: ease of use, multimedia integration, organization capabilities, and security. Web traffic was documented. A 17-question survey was administered to 18 plastic surgeons who used the OCP after 1 year to assess their attitudes and perceptions. From January 13 to May 28, 2010, 413 operations were performed at the field hospital. Of the overall number of procedures, 46.9% were performed by plastic surgery teams. In a year, beginning from January 12, 2011, the OCP had 1117 visits with 530 absolute unique visitors. Of 17 plastic surgeons, 71% responded that the OCP improved follow-up and continuity of care by debriefing rotating plastic surgery teams. One hundred percent claimed that the OCP conveyed the role of plastic surgeons with the public. Results demonstrate the necessity of OCP during disaster relief. Online communication platform permitted secure exchange of surgical management details, follow-up, photos, and miscellaneous necessary recommendations. Posted experiences and field hospital progress assisted in generating substantial awareness regarding the significant role and contribution played by plastic surgeons in disaster relief.

  19. FY2016 Lightweight Materials Annual Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2017-10-31

    The Lightweight Materials research and development (R&D) area within the DOE Vehicle Technologies Office (VTO) provides support and guidance for many cutting-edge automotive technologies under development. Research focuses on addressing critical barriers to commercializing lightweight materials for passenger and commercial vehicles. This report describes the progress made on the research and development projects funded by the Lightweight Materials area.

  20. Plastic spatula with narrow long tip provides higher satisfactory smears for Pap test

    Directory of Open Access Journals (Sweden)

    Pervinder Kaur

    2013-01-01

    Full Text Available Background: Ayre spatula for cervical smear collection is being used despite the suggestion that different modified spatulas provide more satisfactory sampling. Aims: To see whether the cytological pickup improves with the use of long tipped spatula. Setting and Design: Rurally based University Hospital; crossover study. Materials and Methods: Pap smear using Ayre spatula in 500 and with plastic narrow long tip (Szalay spatula in 500 clinic attending women was taken and analyzed. Crossover smears were taken with modified spatula in 163 and using Ayre spatula in 187 women after 2 weeks of initial smears. The same pathologist made cytological reporting for all smears and was unaware of the type of spatula used. Results: Smears from Ayre spatula had significantly higher reports of inadequate smears (94 of 500 vs. 68 of 500 for Ayre and Szalay, respectively; P = 0.032 and it remained so even after crossover (94 of 187 vs. 70 of 163 for Ayre and Szalay, respectively; P = 0.2. Cellular quality appeared better with smears taken using Szalay spatula, but the overall abnormal smear detection rate remained similar with either collection tool (χ2 = 1.5; P = 0.2. Conclusions: Proportion of satisfactory smears is higher when long tip plastic spatula is used for collection of sample.

  1. Plastic spatula with narrow long tip provides higher satisfactory smears for Pap test.

    Science.gov (United States)

    Kaur, Pervinder; Kushtagi, Pralhad

    2013-07-01

    Ayre spatula for cervical smear collection is being used despite the suggestion that different modified spatulas provide more satisfactory sampling. To see whether the cytological pickup improves with the use of long tipped spatula. Rurally based University Hospital; crossover study. Pap smear using Ayre spatula in 500 and with plastic narrow long tip (Szalay) spatula in 500 clinic attending women was taken and analyzed. Crossover smears were taken with modified spatula in 163 and using Ayre spatula in 187 women after 2 weeks of initial smears. The same pathologist made cytological reporting for all smears and was unaware of the type of spatula used. Smears from Ayre spatula had significantly higher reports of inadequate smears (94 of 500 vs. 68 of 500 for Ayre and Szalay, respectively; P = 0.032) and it remained so even after crossover (94 of 187 vs. 70 of 163 for Ayre and Szalay, respectively; P = 0.2). Cellular quality appeared better with smears taken using Szalay spatula, but the overall abnormal smear detection rate remained similar with either collection tool (χ(2) = 1.5; P = 0.2). Proportion of satisfactory smears is higher when long tip plastic spatula is used for collection of sample.

  2. A Systematic Review of Smartphone Applications for Plastic Surgery Providers: Target Audience, Uses, and Cost.

    Science.gov (United States)

    Reusche, Ryan; Buchanan, Patrick J; Kozlow, Jeffrey H; Vercler, Christian J

    2016-01-01

    The growth and acceptance of smartphones among clinicians has been remarkable over the last decade. Over 87% of doctors use a smartphone or tablet capable of running third-party software known as applications (apps). In the field of plastic surgery, apps have been designed for personal practice development, education, clinical tools and guidelines, and entertainment. This study reviews the literature on apps related to plastic surgery and determines the number and types of apps available. A systematic review of the literature was performed to find articles written about plastic surgery applications. Queries were run in the Apple iPhone iOS App store and Google Play using the term "plastic surgery." Apps were reviewed for ratings, downloads, and cost. In addition, apps were categorized based on purpose. Categories include practice development, media/literature, clinical tool and guideline apps, or recreation. The literature search yielded 8 articles for review, 2 articles focused on categorizing apps and 6 articles focused on describing useful apps. Searching Apple's iTunes (iOS) store identified 273 and Google Play identified 250 apps related to plastic surgery; since 2013, a 62%, and 580% increase, respectively. The iOS store included practice development (46%), recreation (26%), media/literature (14%), and clinical tool and guideline (11%). Google Play store included recreation apps (44%), practice development (24%), clinical tools and guidelines (11%), and media and literature (9%). Apps related to the field of plastic surgery are increasing in prevalence. The content of these apps are variable, and the majority are intended for marketing and development of private practices. Apps linking to literature, texts, study materials, and clinical tools and guidelines are developed for both practicing plastic surgeons and surgical trainees. Finding "useful" apps takes time because searches are often complicated by a variety of apps.

  3. ULTRA-LIGHTWEIGHT CEMENT

    International Nuclear Information System (INIS)

    Fred Sabins

    2001-01-01

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). Work reported herein addresses Task 1: Assess Ultra-Lightweight Cementing Issues, Task 2: Review Russian Ultra-Lightweight Cement Literature, Task 3: Test Ultra-Lightweight Cements, and Task 8: Develop Field ULHS Cement Blending and Mixing Techniques. Results reported this quarter include: preliminary findings from a literature review focusing on problems associated with ultra-lightweight cements; summary of pertinent information from Russian ultra-lightweight cement literature review; laboratory tests comparing ULHS slurries to foamed slurries and sodium silicate slurries for two different applications; and initial laboratory studies with ULHS in preparation for a field job

  4. High-flexibility, noncollapsing lightweight hose

    Science.gov (United States)

    Williams, D.A.

    1993-04-20

    A high-flexibility, noncollapsing, lightweight, large-bore, wire-reinforced hose is inside fiber-reinforced PVC tubing that is flexible, lightweight, and abrasion resistant. It provides a strong, kink- and collapse-free conduit for moving large quantities of dangerous fluids, e.g., removing radioactive waste water or processing chemicals.

  5. FY2015 Lightweight Materials R&D Annual Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2016-09-30

    The Lightweight Materials research and development (R&D) area within the DOE Vehicle Technologies Office (VTO) provides support and guidance for many cutting-edge automotive technologies under development. Research focuses on addressing critical barriers to commercializing lightweight materials for passenger and commercial vehicles. This report describes the progress made on the research and development projects funded by the Lightweight Materials area.

  6. LIGHTWEIGHT CONCRETE BASED GRANSHLAK

    Directory of Open Access Journals (Sweden)

    NETESA M. I.

    2016-02-01

    Full Text Available Raising of problem. Concrete advisable to obtain a low strength with local secondary resources for recycling and reduce the environmental burden on the environment. But it is important to design such concrete compositions with a reduced flow of cement. It is known that the coefficient of efficiency of use of cement in the concrete of the heavy and B10 is less than about 0.5, which is almost two times smaller than in class B15 concrete and above. Even lower coefficient of efficiency in light concrete cement low strength. Therefore, it is important to find patterns determining the composition of lightweight concrete based on local-products industry with more efficient use of cement in them. Purpose.. Based on the analysis of earlier research results, including with the use of methods of mathematical planning of experiments to determine the concrete contents, which can provide the requirements for the underlying layers of the floor, the compressive strength of which should correspond to the class B5. It is important to provide the required strength at minimum flow of the cement, which is the most expensive and energy-intensive part of concrete. Conclusion. Analysis of the test results of control samples of concrete in 28-day-old, the following laws. The required tensile strength of concrete compressive strength of 7.0 MPa can be obtained in the test range when used in formulations as a filler as the Dnieper hydroelectric power station fly ash and tailings Krivoy Rog iron ore YuGOK. To ensure providing the required characteristic strength of the concrete in the underlying layers of the floor is advisable to use a nominal composition per cubic meter of concrete: cement 160 kg granshlaka Plant named after Petrovsky, 675 kg of fly ash Dnieper HPP 390 kg, 400 kg of sand, 230 liters of water. Thus, while ensuring rational grain composition components can obtain the desired strength lightweight concrete based granshlaka plant Petrovsky, using as fillers

  7. A lightweight universe?

    Science.gov (United States)

    Bahcall, Neta A.; Fan, Xiaohui

    1998-01-01

    How much matter is there in the universe? Does the universe have the critical density needed to stop its expansion, or is the universe underweight and destined to expand forever? We show that several independent measures, especially those utilizing the largest bound systems known—clusters of galaxies—all indicate that the mass-density of the universe is insufficient to halt the expansion. A promising new method, the evolution of the number density of clusters with time, provides the most powerful indication so far that the universe has a subcritical density. We show that different techniques reveal a consistent picture of a lightweight universe with only ∼20–30% of the critical density. Thus, the universe may expand forever. PMID:9600898

  8. Plastics recycling: challenges and opportunities.

    Science.gov (United States)

    Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward

    2009-07-27

    Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3-4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. These two observations alone indicate that our current use of plastics is not sustainable. In addition, because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide. Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal. Here, we briefly set recycling into context against other waste-reduction strategies, namely reduction in material use through downgauging or product reuse, the use of alternative biodegradable materials and energy recovery as fuel. While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it

  9. Plastics recycling: challenges and opportunities

    Science.gov (United States)

    Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward

    2009-01-01

    Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3–4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. These two observations alone indicate that our current use of plastics is not sustainable. In addition, because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide. Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal. Here, we briefly set recycling into context against other waste-reduction strategies, namely reduction in material use through downgauging or product reuse, the use of alternative biodegradable materials and energy recovery as fuel. While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it

  10. Longevity and plasticity of CFTR provide an argument for noncanonical SNP organization in hominid DNA.

    Directory of Open Access Journals (Sweden)

    Aubrey E Hill

    Full Text Available Like many other ancient genes, the cystic fibrosis transmembrane conductance regulator (CFTR has survived for hundreds of millions of years. In this report, we consider whether such prodigious longevity of an individual gene--as opposed to an entire genome or species--should be considered surprising in the face of eons of relentless DNA replication errors, mutagenesis, and other causes of sequence polymorphism. The conventions that modern human SNP patterns result either from purifying selection or random (neutral drift were not well supported, since extant models account rather poorly for the known plasticity and function (or the established SNP distributions found in a multitude of genes such as CFTR. Instead, our analysis can be taken as a polemic indicating that SNPs in CFTR and many other mammalian genes may have been generated--and continue to accrue--in a fundamentally more organized manner than would otherwise have been expected. The resulting viewpoint contradicts earlier claims of 'directional' or 'intelligent design-type' SNP formation, and has important implications regarding the pace of DNA adaptation, the genesis of conserved non-coding DNA, and the extent to which eukaryotic SNP formation should be viewed as adaptive.

  11. Light-weight plastination.

    Science.gov (United States)

    Steinke, Hanno; Rabi, Suganthy; Saito, Toshiyuki; Sawutti, Alimjan; Miyaki, Takayoshi; Itoh, Masahiro; Spanel-Borowski, Katharina

    2008-11-20

    Plastination is an excellent technique which helps to keep the anatomical specimens in a dry, odourless state. Since the invention of plastination technique by von Hagens, research has been done to improve the quality of plastinated specimens. In this paper, we have described a method of producing light-weight plastinated specimens using xylene along with silicone and in the final step, substitute xylene with air. The finished plastinated specimens were light-weight, dry, odourless and robust. This method requires less use of resin thus making the plastination technique more cost-effective. The light-weight specimens are easy to carry and can easily be used for teaching.

  12. The use of spent glauconite in lightweight aggregate production

    OpenAIRE

    Franus, Wojciech; Franus, Małgorzata; Latosińska, Jolanta; Wójcik, Rafał

    2011-01-01

    The presented work has shown an application of spent glauconite bed after purification of wastewater for production of lightweight expanded clay aggregates. Sewage, from which it was removed Zn ions, came from technological line (zincworks) of Communication Equipment Factory „PZL” Świdnik. Spent glauconite bed was used as an additive in lightweight aggregate production which was obtained using plastic method by sintering, at temperature 1140 ºC and 1200 ºC, of spent glauconite amouts 10, 15, ...

  13. Lightweight design: mass in transit

    OpenAIRE

    MALBURET, François; KRYSINSKI, Tomasz; NAUZIN, Jean-Paul

    2012-01-01

    This paper is part of an effort to reduce a vehicle’s CO2 emissions through lightweight design. The originality of the approach consists in harnessing the optimal vehicle architecture with regard to CO2 emissions. Reducing a vehicle’s weight provides an opportunity to reassess performance features like shock, noise, vibrations and road holding, thereby generating additional savings through a virtuous cycle of weight reduction. The paper sheds light on some methodological aspects used by PSA P...

  14. Adaptive developmental plasticity: Compartmentalized responses to environmental cues and corresponding internal signals provide phenotypic flexibility

    NARCIS (Netherlands)

    Mateus, A.R.A.; Marques-Pita, M.; Oostra, V.; Lafuente, E.; Brakefield, P.M.; Zwaan, B.J.; Beldade, P.

    2014-01-01

    Background The environmental regulation of development can result in the production of distinct phenotypes from the same genotype and provide the means for organisms to cope with environmental heterogeneity. The effect of the environment on developmental outcomes is typically mediated by hormonal

  15. ULTRA-LIGHTWEIGHT CEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Fred Sabins

    2001-10-23

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). Work reported herein addresses tasks performed in the fourth quarter as well as the other three quarters of the past year. The subjects that were covered in previous reports and that are also discussed in this report include: Analysis of field laboratory data of active cement applications from three oil-well service companies; Preliminary findings from a literature review focusing on problems associated with ultra-lightweight cements; Summary of pertinent information from Russian ultra-lightweight cement literature review; and Comparison of compressive strengths of ULHS systems using ultrasonic and crush methods Results reported from the fourth quarter include laboratory testing of ULHS systems along with other lightweight cement systems--foamed and sodium silicate slurries. These comparison studies were completed for two different densities (10.0 and 11.5 lb/gal) and three different field application scenarios. Additional testing included the mechanical properties of ULHS systems and other lightweight systems. Studies were also performed to examine the effect that circulation by centrifugal pump during mixing has on breakage of ULHS.

  16. Plasticity theory

    CERN Document Server

    Lubliner, Jacob

    2008-01-01

    The aim of Plasticity Theory is to provide a comprehensive introduction to the contemporary state of knowledge in basic plasticity theory and to its applications. It treats several areas not commonly found between the covers of a single book: the physics of plasticity, constitutive theory, dynamic plasticity, large-deformation plasticity, and numerical methods, in addition to a representative survey of problems treated by classical methods, such as elastic-plastic problems, plane plastic flow, and limit analysis; the problem discussed come from areas of interest to mechanical, structural, and

  17. Vibro-acoustics of lightweight sandwich structures

    CERN Document Server

    Lu, Tianjian

    2014-01-01

    Vibro-Acoustics of Lightweight Sandwich Structures introduces the study of the coupled vibration and acoustic behavior of lightweight sandwich structures in response to harmonic force and sound pressure. This book focuses on the theoretical modeling and experimental investigation of lightweight sandwich structures in order to provide a predictive framework for vibro-acoustic characteristics of typical engineering structures. Furthermore, by developing solution tools, it concentrates on the influence of key systematic parameters leading to effective guidance for optimal structure design toward lightweight, high-stiffness and superior sound insulation capability. This book is intended for researchers, scientists, engineers and graduate students in mechanical engineering especially in structural mechanics, mechanics and acoustics. Fengxian Xin and Tianjian Lu both work at the School of Aerospace, Xi’an Jiaotong University.

  18. Cryptanalysis of Some Lightweight Symmetric Ciphers

    DEFF Research Database (Denmark)

    Abdelraheem, Mohamed Ahmed Awadelkareem Mohamed Ahmed

    In recent years, the need for lightweight encryption systems has been increasing as many applications use RFID and sensor networks which have a very low computational power and thus incapable of performing standard cryptographic operations. In response to this problem, the cryptographic community...... on a variant of PRESENT with identical round keys. We propose a new attack named the Invariant Subspace Attack that was specifically mounted against the lightweight block cipher PRINTcipher. Furthermore, we mount several attacks on a recently proposed stream cipher called A2U2....... of the international standards in lightweight cryptography. This thesis aims at analyzing and evaluating the security of some the recently proposed lightweight symmetric ciphers with a focus on PRESENT-like ciphers, namely, the block cipher PRESENT and the block cipher PRINTcipher. We provide an approach to estimate...

  19. Investigation on Wall Panel Sandwiched With Lightweight Concrete

    Science.gov (United States)

    Lakshmikandhan, K. N.; Harshavardhan, B. S.; Prabakar, J.; Saibabu, S.

    2017-08-01

    The rapid population growth and urbanization have made a massive demand for the shelter and construction materials. Masonry walls are the major component in the housing sector and it has brittle characteristics and exhibit poor performance against the uncertain loads. Further, the structure requires heavier sections for carrying the dead weight of masonry walls. The present investigations are carried out to develop a simple, lightweight and cost effective technology for replacing the existing wall systems. The lightweight concrete is developed for the construction of sandwich wall panel. The EPS (Expanded Polystyrene) beads of 3 mm diameter size are mixed with concrete and developed a lightweight concrete with a density 9 kN/m3. The lightweight sandwich panel is cast with a lightweight concrete inner core and ferrocement outer skins. This lightweight wall panel is tested for in-plane compression loading. A nonlinear finite element analysis with damaged plasticity model is carried out with both material and geometrical nonlinearities. The experimental and analytical results were compared. The finite element study predicted the ultimate load carrying capacity of the sandwich panel with reasonable accuracy. The present study showed that the lightweight concrete is well suitable for the lightweight sandwich wall panels.

  20. Transcranial magnetic stimulation provides means to assess cortical plasticity and excitability in humans with fragile X syndrome and autism spectrum disorder

    Directory of Open Access Journals (Sweden)

    Lindsay M Oberman

    2010-06-01

    Full Text Available Fragile X Syndrome (FXS is the most common heritable cause of intellectual disability. In vitro electrophysiologic data from mouse models of FXS suggest that loss of Fragile X Mental Retardation Protein (FMRP affects intracortical excitability and synaptic plasticity. Specifically, the cortex appears hyperexcitable, and use-dependent long-term potentiation (LTP and long-term depression (LTD of synaptic strength are abnormal. Though animal models provide important information, FXS and other neurodevelopmental disorders are human diseases and as such translational research to evaluate cortical excitability and plasticity must be applied in the human. Transcranial magnetic stimulation (TMS paradigms have recently been developed to noninvasively investigate cortical excitability using paired-pulse stimulation, as well as LTP- and LTD-like synaptic plasticity in response to theta burst stimulation (TBS in vivo in the human. TBS applied on consecutive days can be used to measure metaplasticity (the ability of the synapse to undergo a second plastic change following a recent induction of plasticity. The current study investigated intracortical inhibition, plasticity and metaplasticity in full mutation females with FXS, participants with autism spectrum disorders (ASD, and neurotypical controls. Results suggest that intracortical inhibition is normal in participants with FXS, while plasticity and metaplasticity appear abnormal. ASD participants showed abnormalities in plasticity and metaplasticity, as well as heterogeneity in intracortical inhibition. Our findings highlight the utility of noninvasive neurophysiological measures to translate insights from animal models to humans with neurodevelopmental disorders, and thus provide direct confirmation of cortical dysfunction in patients with FXS and ASD.

  1. ULTRA-LIGHTWEIGHT CEMENT

    International Nuclear Information System (INIS)

    Fred Sabins

    2001-01-01

    The objective of this project is to develop an improved ultra-lightweight cement using ultralight hollow glass spheres (ULHS). Work reported herein addresses Task 1: Assess Ultra-Lightweight Cementing Problems and Task 3: Test Ultra-Lightweight Cements. Results reported this quarter include a review and summary of Halliburton Energy Services (HES) and BJ Services historical performance data for lightweight cement applications. These data are analyzed and compared to ULHS cement and foamed cement performances. Similar data is expected from Schlumberger, and an analysis of this data will be completed in the following phases of the project. Quality control testing of materials used to formulate ULHS cements in the laboratory was completed to establish baseline material performance standards. A testing protocol was developed employing standard procedures as well as procedures tailored to evaluate ULHS and foamed cement. This protocol is presented and discussed. Results of further testing of ULHS cements are presented along with an analysis to establish cement performance design criteria to be used during the remainder of the project. Finally, a list of relevant literature on lightweight cement performance is compiled for review during the next quarter

  2. Spark Ignition of Combustible Vapor in a Plastic Bottle as a Demonstration of Rocket Propulsion

    Science.gov (United States)

    Mattox, J. R.

    2017-01-01

    I report an innovation that provides a compelling demonstration of rocket propulsion, appropriate for students of physics and other physical sciences. An electrical spark is initiated from a distance to cause the deflagration of a combustible vapor mixed with air in a lightweight plastic bottle that is consequently propelled as a rocket by the…

  3. Do studies on cortical plasticity provide a rationale for using non invasive brain stimulation as a treatment for Parkinson’s disease patients?

    Directory of Open Access Journals (Sweden)

    Giacomo eKoch

    2013-11-01

    Full Text Available Animal models of Parkinson’s disease (PD have shown that key mechanisms of cortical plasticity such as long-term potentiation (LTP and long-term depression (LTD can be impaired by the PD pathology. In humans protocols of non-invasive brain stimulation, such as paired associative stimulation (PAS and theta burst stimulation (TBS, can be used to investigate cortical plasticity of the primary motor cortex. Through the amplitude of the motor evoked potential (MEP these transcranial magnetic stimulation methods allow to measure both LTP-like and LTD-like mechanisms of cortical plasticity. So far these protocols have reported some controversial findings when tested in PD patients. While various studies described evidence for reduced LTP- and LTD-like plasticity, others showed different results, demonstrating increased LTP-like and normal LTD-like plasticity. Recent evidence provided support to the hypothesis that these different patterns of cortical plasticity likely depend on the stage of the disease and on the concomitant administration of levo-dopa. However, it still unclear how and if these altered mechanisms of cortical plasticity can be taken as a reliable model to build appropriate protocols aimed at treating PD symptoms b

  4. Mechanical Properties of Steel Fiber Reinforced all Lightweight Aggregate Concrete

    Science.gov (United States)

    Yang, Y. M.; Li, J. Y.; Zhen, Y.; Nie, Y. N.; Dong, W. L.

    2018-05-01

    In order to study the basic mechanical properties and failure characteristics of all lightweight aggregate concrete with different volume of steel fiber (0%, 1%, 2%), shale ceramsite is used as light coarse aggregate. The shale sand is made of light fine aggregate and mixed with different volume of steel fiber, and the mix proportion design of all lightweight aggregate concrete is carried out. The cubic compressive strength, axial compressive strength, flexural strength, splitting strength and modulus of elasticity of steel fiber all lightweight aggregate concrete were studied. Test results show that the incorporation of steel fiber can restrict the cracking of concrete, improve crack resistance; at the same time, it shows good plastic deformation ability and failure morphology. It lays a theoretical foundation for further research on the application of all lightweight aggregate concrete in structural systems.

  5. Lightweight Bathrooms with Increased Durability

    DEFF Research Database (Denmark)

    Morelli, Martin; Brandt, Erik

    2017-01-01

    vulnerable and less robust than the old type of heavy wet rooms made from concrete and masonry. For example damage due to ingress of water and moisture in a lightweight construction is normally associated with very expensive repair work. However, they might perform fully satisfactorily on condition...... wet room floor made with 2 watertight layers separated by an inorganic layer e.g. fibre reinforced concrete. Both layers are drained to the floor gully in order to reduce the risk of damage from leaks in the watertight layer; i.e. if one layer fails, the layer beneath will be able to provide...

  6. FY2014 Lightweight Materials R&D Annual Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-03-01

    The Lightweight Materials research and development (R&D) area within the DOE Vehicle Technologies Office (VTO) provides support and guidance for many cutting-edge automotive technologies under development. Research focuses on addressing critical barriers to commercializing lightweight materials for passenger and commercial vehicles.

  7. High-Pressure Lightweight Thrusters

    Science.gov (United States)

    Holmes, Richard; McKechnie, Timothy; Shchetkovskiy, Anatoliy; Smirnov, Alexander

    2013-01-01

    interface realizes pseudo-plastic behavior with significant increase in the tensile strength. The investigation of high-temperature strength of C/Cs under high-rate heating (critical for thrust chambers) shows that tensile and compression strength increases from 70 MPa at room temperature to 110 MPa at 1,773 K, and up to 125 MPa at 2,473 K. Despite these unique properties, the use of C/Cs is limited by its high oxidation rate at elevated temperatures. Lining carbon/carbon chambers with a thin layer of iridium or iridium and rhenium is an innovative way to use proven refractory metals and provide the oxidation barrier necessary to enable the use of carbon/ carbon composites. Due to the lower density of C/Cs as compared to SiC/SiC composites, an iridium liner can be added to the C/C structure and still be below the overall thruster weight. Weight calculations show that C/C, C/C with 50 microns of Ir, and C/C with 100 microns of Ir are of less weight than alternative materials for the same construction.

  8. The Design of a Lightweight RFID Middleware

    Directory of Open Access Journals (Sweden)

    Fengqun Lin

    2009-10-01

    Full Text Available Radio Frequency Identification (RFID middleware is often regarded as the central nervous system of RFID systems. In this paper, a lightweight RFID middleware is designed and implemented without the need of an Application Level Events (ALE structure, and its implementation process is described using a typical commerical enterprise. A short review of the current RFID middleware research and development is also included. The characteristics of RFID middleware are presented with a two-centric framework. The senarios of RFID data integration based on the simplified structure are provided to illuminats the design and implementation of the lightweight middleware structure and its development process. The lightweight middleware is easy to maintain and extend because of the simplified and streamlined structure and the short development cycle.

  9. Lightweight Cryptography for Passive RFID Tags

    DEFF Research Database (Denmark)

    David, Mathieu

    2012-01-01

    were mostly unsatisfactory. As a conclusion, a new branch of cryptography, commonly called Lightweight Cryptography, emerged to address the issues of these tiny ubiquitous devices. This Thesis presents a comprehensive engineering to lightweight cryptography, proposes a classification and explores its...... various ramifications by giving key examples in each of them. We select two of these branches, ultralightweight cryptography and symmetric-key cryptography, and propose a cryptographic primitive in each of them. In the case of symmetric-key cryptography, we propose a stream cipher that has a footprint...... of an integrator for a particular application. Finally, we conclude that the research for finding robust cryptographic primitive in the branch of lightweight cryptography still has some nice days ahead, and that providing a secure cryptosystem for printed electronics RFID tags remains an open research topic....

  10. LIGHT-WEIGHT LOAD-BEARING STRUCTURE

    DEFF Research Database (Denmark)

    2009-01-01

    The invention relates to a light-weight load-bearing structure (1) with optimized compression zone (2), where along one or more compression zones (2) in the structure (1) to be cast a core (3) of strong concrete is provided, which core (3) is surrounded by concrete of less strength (4) compared...... to the core (3) of strong concrete. The invention also relates to a method of casting of light-weight load-bearing structures (1) with optimized compression zone (2) where one or more channels, grooves, ducts, pipes and/or hoses (5) formed in the load-bearing structure (1) serves as moulds for moulding one...... or more cores (3) of strong concrete in the light-weight load-bearing structure (1)....

  11. FY 2012 Lightweight Materials Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-04-15

    The FY 2012 Annual Progress Report for Lightweight Materials provides a detailed description of the activities and technical accomplishments which focuses on the development and validation of advanced materials and manufacturing technologies to significantly reduce light and heavy duty vehicle weight without compromising other attributes such as safety, performance, recyclability, and cost.

  12. Olive pomace based lightweight concrete, an experimental approach and contribution

    Directory of Open Access Journals (Sweden)

    Lynda Amel Chaabane

    2018-01-01

    Full Text Available Due to conventional aggregates resources depletion, material recycling has become an economic and ecologic alternative. In this paper, locally available natural residues such as olive pomace were investigated, when partially incorporated in the concrete formulation, since the mechanical characteristics of lightweight aggregate concrete strongly depend on its properties and proportions. Lightweight aggregates are more deformable than the cement matrix because of their high porosity, and their influence on the concrete strength remains complex. The purpose of this paper is to investigate the aggregates properties on lightweight concrete mechanical behaviour through an experimental approach. In addition, the different substitution sequences and the W/C ratio on lightweight concrete behaviour were evaluated, in order to determine the W/C ratio influence on the improvement of the lightweight concrete mechanical properties while knowing that the mixing water quantity gives the cement paste manoeuvrability and mechanical strength effects. The last part of this paper, therefore, was to provide statistical survey for estimating strength and weight reduction through the different natural aggregate substitutions to improve the lightweight concrete properties. The results achieved in a significant olive-pomace lower adhesion with the matrix after the cement setting, making the lightweight concrete mechanical strength weak. However, this work can open several perspectives: Results modeling and correlation with an experimental approach, the evolution and determination of lightweight concrete characteristics when exposed to high temperatures and thermohydric properties.

  13. EVOLUTION OF LIGHTWEIGHT WOOD COMPOSITES

    Directory of Open Access Journals (Sweden)

    Marius C. BARBU

    2016-01-01

    Full Text Available Lightweight boards and beams in the wood-based construction and furniture industry are not a new topic. The density reduction of panels using sandwich structure with light cores was confirmed by users like doors or mobile homes more than three decades ago. Today many ways to attain a lighter wooden structure are on offer, partially in industrial application. The first one is the use of light-weight wood species like balsa, lime, pine from southern hemisphere plantations etc. limited by the availability, strength properties, gluability and so on. A second one is the sandwich structure made from hard faces like thick veneer, thin plywood, particleboard or high density thin fiberboard and cores made from honeycomb paper, very light wood species or foams like the polystyrene one. A third way to produce a light structure is to reduce the core drastically, using predesigned skeletons with special shapes and connections to the faces. The engines for these developments are on the one hand the fast growing market of knockdown furniture and on the other hand the increasing costs for energy and raw materials. Additional factors that make weight saving a primary economical objective for most producers are transportation costs, easier handling and higher acceptance among the end users. Moreover, customers demand more for ergonomical solutions regarding packaging. Many patents were generated by researchers and developers for new one-stage production processes for sandwich panels with wood- and impregnated paper-based facings made from veneers, particles or fibres and a core consisting of expandable foams, particles or embedded hard skeletons. These ideas or prototypes could be integrated in existing continuous pressing lines for wood based panels keeping some of the advantages of the continuous production technique in matters of efficiency. Some of the challenges of the light weight wooden structure are the connection in half or final parts, resistance to

  14. Lightweight enterprise architectures

    CERN Document Server

    Theuerkorn, Fenix

    2004-01-01

    STATE OF ARCHITECTUREArchitectural ChaosRelation of Technology and Architecture The Many Faces of Architecture The Scope of Enterprise Architecture The Need for Enterprise ArchitectureThe History of Architecture The Current Environment Standardization Barriers The Need for Lightweight Architecture in the EnterpriseThe Cost of TechnologyThe Benefits of Enterprise Architecture The Domains of Architecture The Gap between Business and ITWhere Does LEA Fit? LEA's FrameworkFrameworks, Methodologies, and Approaches The Framework of LEATypes of Methodologies Types of ApproachesActual System Environmen

  15. Plastic waste as a resource. Strategies for reduction and utilization of plastic waste

    OpenAIRE

    Pasqual i Camprubí, Gemma

    2010-01-01

    Plastic materials have experienced a spectacular rate of growth in recent decades, consequently, production of plastics, and likewise their consumption, has increased markedly since 1950. Moreover, they are lightweight and durable, as well as can be moulded into a variety of products that can be manufactured in many different types of plastic and in a wide range of applications. Inevitably, continually increasing amounts of used plastic are originating daily, resulting in a plastic waste prob...

  16. Lightweight superconducting alternators

    International Nuclear Information System (INIS)

    Keim, T.A.

    1988-01-01

    One of the most efficient and most lightweight means of converting high-temperature heat energy to electricity is a turboalternator set. Turboalternators are potentially important components of burst-mode power systems, either chemical or nuclear powered. Also, they are probable key components in future electric propulsion systems. Existing examples of multimegawatt turbomachines have been optimized for a variety of aerospace uses, ranging from aircraft propulsion to rocket engine fuel pump drives. There is no corresponding history of multimegawatt alternators built to aerospace standards of mass, performance, and reliability. This paper discusses one of the few such development efforts presently in progress, and gives an indication of possible future potential. In large power ratings, superconducting generators offer substantial power density, specific weight, and efficiency advantages over competing technologies. A program at GE has led to the construction of a lightweight high-voltage 20-MW generator with a superconducting field winding. The first part of this paper describes the design of the generator. The second projects the capabilities of the generator to other ratings

  17. RFID security a lightweight paradigm

    CERN Document Server

    Khattab, Ahmed; Amini, Esmaeil; Bayoumi, Magdy

    2017-01-01

    This book provides a comprehensive treatment of security in the widely adopted, Radio Frequency Identification (RFID) technology. The authors present the fundamental principles of RFID cryptography in a manner accessible to a broad range of readers, enabling them to improve their RFID security design. This book also offers the reader a range of interesting topics portraying the current state-of-the-art in RFID technology and how it can be integrated with today’s Internet of Things (IoT) vision. The authors describe a first-of-its-kind, lightweight symmetric authenticated encryption cipher called Redundant Bit Security (RBS), which enables significant, multi-faceted performance improvements compared to existing cryptosystems. This book is a must-read for anyone aiming to overcome the constraints of practical implementation in RFID security technologies.

  18. In-Situ Characterization of Deformation and Fracture Behavior of Hot-Rolled Medium Manganese Lightweight Steel

    Science.gov (United States)

    Zhao, Zheng-zhi; Cao, Rong-hua; Liang, Ju-hua; Li, Feng; Li, Cheng; Yang, Shu-feng

    2018-02-01

    The deformation and fracture behavior of hot-rolled medium manganese lightweight (0.32C-3.85Mn-4.18Al-1.53Si) steel was revealed by an in situ tensile test. Deformed δ-ferrite with plenty of cross-parallel deformation bands during in situ tensile tests provides δ-ferrite of good plasticity and ductility, although it is finally featured by the cleavage fracture. The soft and ductile δ-ferrite and high-volume fraction of austenite contribute to the superior mechanical properties of medium manganese lightweight steel heated at 800°C, with a tensile strength of 924 MPa, total elongation of 35.2% and product of the strength and elongation of 32.5 GPa %.

  19. Comprehensive review of methicillin-resistant Staphylococcus aureus: screening and preventive recommendations for plastic surgeons and other surgical health care providers.

    Science.gov (United States)

    O'Reilly, Eamon B; Johnson, Mark D; Rohrich, Rod J

    2014-11-01

    Up to 2.3 million people are colonized with methicillin-resistant Staphylococcus aureus in the United States, causing well-documented morbidity and mortality. Although the association of clinical outcomes with community and hospital carriage rates is increasingly defined, less is reported about asymptomatic colonization prevalence among physicians, and specifically plastic surgeons and the subsequent association with the incidence of patient surgical-site infection. A review of the literature using the PubMed and Cochrane databases analyzing provider screening, transmission, and prevalence was undertaken. In addition, a search was completed for current screening and decontamination guidelines and outcomes. The methicillin-resistant S. aureus carriage prevalence of surgical staff is 4.5 percent. No prospective data exist regarding transmission and interventions for plastic surgeons. No studies were found specifically looking at prevalence or treatment of plastic surgeons. Current recommendations by national organizations focus on patient-oriented point-of-care testing and intervention, largely ignoring the role of the health care provider. Excellent guidelines exist regarding screening, transmission prevention, and treatment both in the workplace and in the community. No current such guidelines exist for plastic surgeons. No Level I or II evidence was found regarding physician screening, treatment, or transmission. Current expert opinion, however, indicates that plastic surgeons and their staff should be vigilant for methicillin-resistant S. aureus transmission, and once a sentinel cluster of skin and soft-tissue infections is identified, systematic screening and decontamination should be considered. If positive, topical decolonization therapy should be offered. In refractory cases, oral antibiotic therapy may be required, but this should not be used as a first-line strategy.

  20. Metallic stents provide better QOL than plastic stents in patients with stricture of unresectable advanced esophageal cancer

    International Nuclear Information System (INIS)

    Ohta, Kazuki; Nagahara, Akihito; Iijima, Katsuyori

    2006-01-01

    The aim of this study was to elucidate the utility and safety of treatment with esophageal stents (plastic and metallic stents) for unresectable advanced esophageal cancer. Between 1992 and 2002, 14 cases of unresectable advanced esophageal cancer were treated with esophageal stents (the plastic stent group, 7 cases; and the metallic stent group, 7 cases). Of these, 10 cases had a history of chemotherapy and or radiotherapy. An improvement in oral intake and performance status (PS), survival time, periods at home, and adverse events were compared between the two groups. After stenting, oral intake and PS were significantly improved in the metallic stent group. Follow-up at home was possible in 71.4%. There was no significant difference in survival or duration of time at home between the two groups. All adverse events were controllable and there was no difference between the two groups. Stenting not only improved oral intake and PS but also allowed a stay at home, resulting in a marked improvement in patients' quality of life (QOL). Stenting was performed safely even in cases with a history of radiotherapy. There was no difference in survival, ratios of staying at home, and safety between the two groups, but QOL was significantly improved in the metallic stent group. These outcomes indicate that placement of metallic stents should be actively considered to treat stricture due to advanced esophageal cancer. (author)

  1. Annotating Evidence Based Clinical Guidelines : A Lightweight Ontology

    NARCIS (Netherlands)

    Hoekstra, R.; de Waard, A.; Vdovjak, R.; Paschke, A.; Burger, A.; Romano, P.; Marshall, M.S.; Splendiani, A.

    2012-01-01

    This paper describes a lightweight ontology for representing annotations of declarative evidence based clinical guidelines. We present the motivation and requirements for this representation, based on an analysis of several guidelines. The ontology provides the means to connect clinical questions

  2. Security Isolation Strategy Mechanism for Lightweight Virtualization Environment

    Directory of Open Access Journals (Sweden)

    Liu Qian

    2017-01-01

    Full Text Available For cloud service providers, lightweight virtualization is a more economical way of virtualization. While the user is worried about the safety of applications and data of the container, due to the container sharing the underlying interface and the kernel, therefore the security and trusted degree of lightweight virtualization container isolation mechanism is critical for the promotion of lightweight virtualization service. Because the user cannot directly participate in the process of the construction and management of container isolation mechanism, it is difficult for them to establish confidence in the security and trusted degree of container isolation mechanism. Based on the research and analysis of system credible and virtualization isolation mechanism, this paper puts forward a set of lightweight virtualization security isolation strategy mechanism, divides lightweight virtualization container storage address space into several parts, puts forward the definition of lightweight virtualization security isolation, gives the formal description and proof of container security isolation strategy, and combines with related technology to verify the feasibility of lightweight virtualization security isolation strategy mechanism. The mechanism has important guiding significance for cloud services providers to deploy container security isolation.

  3. Lightweight flywheel containment

    Science.gov (United States)

    Smith, James R.

    2004-06-29

    A lightweight flywheel containment composed of a combination of layers of various material which absorb the energy of a flywheel structural failure. The various layers of material act as a vacuum barrier, momentum spreader, energy absorber, and reaction plate. The flywheel containment structure has been experimentally demonstrated to contain carbon fiber fragments with a velocity of 1,000 m/s and has an aerial density of less than 6.5 g/square centimeters. The flywheel containment, may for example, be composed of an inner high toughness structural layer, and energy absorbing layer, and an outer support layer. Optionally, a layer of impedance matching material may be utilized intermediate the flywheel rotor and the inner high toughness layer.

  4. MODULTEC - Modular technology for lightweight vehicles; MODULTEC - Modultechnologie fuer Leichtmobile

    Energy Technology Data Exchange (ETDEWEB)

    Horlacher, M.; Efler, T.; Wegmann, S.

    2003-07-01

    This final report for the Swiss Federal Office of Energy presents the results of two research projects (MODULTEC I and II) that were carried out between 1995 and 2002. The project's aims were to develop and assess components for light-weight car bodies, study and test novel reinforced plastic materials and to examine the industrial implementation of light-weight vehicles. The report presents details on prototype vehicles and transport systems, as well as crash tests. The development of compound plastics and appropriate adhesives is discussed as is the co-operation with various industrial partners. Various prototype components are described and other associated topics such as recycling, storage of alternative fuels and pedestrian protection issues are discussed.

  5. Evaluating the time-dependent and bond characteristics of lightweight concrete mixes for Kansas prestressed concrete bridges.

    Science.gov (United States)

    2011-07-01

    This report details results from testing that was conducted to determine the bond and time-dependent : characteristics of two lightweight concrete mixes. The lightweight mixes were evaluated to possibly : provide a more cost-effective solution to rep...

  6. Acoustic Modeling of Lightweight Structures: A Literature Review

    Science.gov (United States)

    Yang, Shasha; Shen, Cheng

    2017-10-01

    This paper gives an overview of acoustic modeling for three kinds of typical lightweight structures including double-leaf plate system, stiffened single (or double) plate and porous material. Classical models are citied to provide frame work of theoretical modeling for acoustic property of lightweight structures; important research advances derived by our research group and other authors are introduced to describe the current state of art for acoustic research. Finally, remaining problems and future research directions are concluded and prospected briefly

  7. Lightweight Robotic Excavation, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Robust, lightweight, power-efficient excavation robots are mission enablers for lunar outposts and surface systems. Lunar excavators of this type cost-effectively...

  8. The Portuguese plastic carrier bag tax: The effects on consumers' behavior.

    Science.gov (United States)

    Martinho, Graça; Balaia, Natacha; Pires, Ana

    2017-03-01

    Marine litter from lightweight plastic bags is a global problem that must be solved. A plastic bag tax was implemented in February 2015 to reduce the consumption of plastic grocery bags in Portugal and in turn reduce the potential contribution to marine litter. This study analyzes the effect of the plastic bag tax on consumer behavior to learn how it was received and determine the perceived effectiveness of the tax 4months after its implementation. In addition, the study assessed how proximity to coastal areas could influence behaviors and opinions. The results showed a 74% reduction of plastic bag consumption with a simultaneously 61% increase of reusable plastic bags after the tax was implemented. Because plastic bags were then reused for shopping instead of garbage bags, however, the consumption of garbage bags increased by 12%. Although reduction was achieved, the tax had no effect on the perception of marine litter or the impact of plastic bags on environment and health. The majority of respondents agree with the tax but view it as an extra revenue to the State. The distance to the coast had no meaningful influence on consumer behavior or on the perception of the tax. Although the tax was able to promote the reduction of plastics, the role of hypermarkets and supermarkets in providing alternatives through the distribution of reusable plastic bags was determinant to ensuring the reduction. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Plastics recycling: challenges and opportunities

    OpenAIRE

    Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward

    2009-01-01

    Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3–4% is expended to pro...

  10. Lightweight, Thermally Insulating Structural Panels

    Science.gov (United States)

    Eisen, Howard J.; Hickey, Gregory; Wen, Liang-Chi; Layman, William E.; Rainen, Richard A.; Birur, Gajanana C.

    1996-01-01

    Lightweight, thermally insulating panels that also serve as structural members developed. Honeycomb-core panel filled with low-thermal-conductivity, opacified silica aerogel preventing convection and minimizes internal radiation. Copper coating on face sheets reduces radiation. Overall thermal conductivities of panels smaller than state-of-art commercial non-structurally-supporting foam and fibrous insulations. On Earth, panels suitable for use in low-air-pressure environments in which lightweight, compact, structurally supporting insulation needed; for example, aboard high-altitude aircraft or in partially evacuated panels in refrigerators.

  11. Production of lightweight Geopolymer concrete using artificial local lightweight aggregate

    Directory of Open Access Journals (Sweden)

    Abbas Waleed

    2018-01-01

    Full Text Available Due to the rapid depletion of natural resources, the use of waste materials and by-products from different industries of building construction has been gaining increased attention. Geopolymer concrete based on Pozzolana is a new material that does not need the presence of Portland cement as a binder. The main focus of this research is to produce lightweight geopolymer concrete (LWGPC using artificial coarse lightweight aggregate which produced from locally available bentonite clays. In this investigation, the binder is low calcium fly ash (FA and the alkali activator is sodium hydroxide and sodium silicate in different molarities. The experimental tests including workability, fresh density, also, the compressive strength, splitting tensile strength, flexural strength, water absorption and ultrasonic pulse velocity at the age of 7, 28 and 56 days were studied. The oven dry density and thermal conductivity at 28 days age are investigated. The results show that it is possible to produce high strength lightweight geopolymer concrete successfully used as insulated structural lightweight concrete. The 28-day compressive strength, tensile strength, flexural strength, dry density, and thermal conductivity of the produced LWGPC are 35.8 MPa, 2.6MPa, 5.5 MPa, 1835kg/m3, and 0.9567 W/ (m. K, respectively.

  12. Hierarchical resilience with lightweight threads

    International Nuclear Information System (INIS)

    Wheeler, Kyle Bruce

    2011-01-01

    This paper proposes methodology for providing robustness and resilience for a highly threaded distributed- and shared-memory environment based on well-defined inputs and outputs to lightweight tasks. These inputs and outputs form a failure 'barrier', allowing tasks to be restarted or duplicated as necessary. These barriers must be expanded based on task behavior, such as communication between tasks, but do not prohibit any given behavior. One of the trends in high-performance computing codes seems to be a trend toward self-contained functions that mimic functional programming. Software designers are trending toward a model of software design where their core functions are specified in side-effect free or low-side-effect ways, wherein the inputs and outputs of the functions are well-defined. This provides the ability to copy the inputs to wherever they need to be - whether that's the other side of the PCI bus or the other side of the network - do work on that input using local memory, and then copy the outputs back (as needed). This design pattern is popular among new distributed threading environment designs. Such designs include the Barcelona STARS system, distributed OpenMP systems, the Habanero-C and Habanero-Java systems from Vivek Sarkar at Rice University, the HPX/ParalleX model from LSU, as well as our own Scalable Parallel Runtime effort (SPR) and the Trilinos stateless kernels. This design pattern is also shared by CUDA and several OpenMP extensions for GPU-type accelerators (e.g. the PGI OpenMP extensions).

  13. Alternating gender incongruity: a new neuropsychiatric syndrome providing insight into the dynamic plasticity of brain-sex.

    Science.gov (United States)

    Case, Laura K; Ramachandran, Vilayanur S

    2012-05-01

    , which we are currently exploring. Second, we base our hypotheses on ancient and modern associations between the left and right hemispheres and the male and female genders. By providing a case of sharp brain-sex shifts within individuals, we believe that the study of AGI could prove illuminating to scientific understanding of gender, body representation, and the nature of self. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Spongent: A lightweight hash function

    DEFF Research Database (Denmark)

    Bogdanov, Andrey; Knežević, Miroslav; Leander, Gregor

    2011-01-01

    This paper proposes spongent - a family of lightweight hash functions with hash sizes of 88 (for preimage resistance only), 128, 160, 224, and 256 bits based on a sponge construction instantiated with a present-type permutation, following the hermetic sponge strategy. Its smallest implementations...

  15. A Lightweight Protocol for Secure Video Streaming.

    Science.gov (United States)

    Venčkauskas, Algimantas; Morkevicius, Nerijus; Bagdonas, Kazimieras; Damaševičius, Robertas; Maskeliūnas, Rytis

    2018-05-14

    The Internet of Things (IoT) introduces many new challenges which cannot be solved using traditional cloud and host computing models. A new architecture known as fog computing is emerging to address these technological and security gaps. Traditional security paradigms focused on providing perimeter-based protections and client/server point to point protocols (e.g., Transport Layer Security (TLS)) are no longer the best choices for addressing new security challenges in fog computing end devices, where energy and computational resources are limited. In this paper, we present a lightweight secure streaming protocol for the fog computing "Fog Node-End Device" layer. This protocol is lightweight, connectionless, supports broadcast and multicast operations, and is able to provide data source authentication, data integrity, and confidentiality. The protocol is based on simple and energy efficient cryptographic methods, such as Hash Message Authentication Codes (HMAC) and symmetrical ciphers, and uses modified User Datagram Protocol (UDP) packets to embed authentication data into streaming data. Data redundancy could be added to improve reliability in lossy networks. The experimental results summarized in this paper confirm that the proposed method efficiently uses energy and computational resources and at the same time provides security properties on par with the Datagram TLS (DTLS) standard.

  16. Lightweight males of Podisus nigrispinus (Heteroptera: Pentatomidae neglect lightweight females due low reproductive fitness

    Directory of Open Access Journals (Sweden)

    A. I. A. Pereira

    Full Text Available Abstract Sexual choice by male stink bugs is important because females that experience food shortages lay fewer eggs with lower viability compared with well-fed females. In this study, we investigated whether Podisus nigrispinus (Dallas (Heteroptera: Pentatomidae males fed with a low-quality diet during its nymphal stage show selectivity for sexual partners resulting in high-quality progeny. Lightweight males and females were obtained from nymphs fed weekly with Tenebrio molitor L. (Coleoptera: Tenebrionidae pupae. By contrast, heavyweight males and females were fed three times a week and received an extra nutritional source: cotton leaves, Gossypium hirsutum L. (Malvaceae. Lightweight males preferred to mate with heavy females (77.78 ± 14.69%, whereas heavyweight males did not discriminated between light or heavyweight females. Females mated with lightweight males showed similar levels of reproduction to those mated with heavyweight males. The results provide an indication of the importance of male and female body weight for sexual selection in Asopinae stink bugs.

  17. Lightweight Space Tug body structure

    International Nuclear Information System (INIS)

    Lager, J.R.

    1976-01-01

    Lightweight honeycomb sandwich construction using a wide variety of metal and fibrous composite faceskins was used in the design of a typical Space Tug skirt structure. Relatively low magnitude combined loading of axial compression and torsion resulted in designs using ultrathin faceskins, light-weight honeycomb cores, and thin faceskin/core adhesive bond layers. Two of the designs with metal faceskins (aluminum and titanium) and four with fibrous composite faceskins (using combinations of fiberglass, boron, and graphite) were evaluated through the fabrication and structural test of a series of small development panels. The two most promising concepts with aluminum and graphite/epoxy faceskins, were further evaluated through the fabrication and structural test of larger compression and shear panels. All panels tested exceeded design ultimate load levels, thereby, verifying the structural integrity of the selected designs. Projected skirt structural weights for the graphite/epoxy and aluminum concepts fall within original weight guidelines established for the Space Tug vehicle

  18. Applications of Foamed Lightweight Concrete

    Directory of Open Access Journals (Sweden)

    Mohd Sari Kamarul Aini

    2017-01-01

    Full Text Available Application of foamed concrete is increasing at present due to high demand on foamed concrete structures with good mechanical and physical properties. This paper discusses on the use of basic raw materials, their characteristics, production process, and their application in foamed lightweight concrete with densities between 300 kg/m3 and 1800 kg/m3. It also discusses the factors that influence the strengths and weaknesses of foamed concrete based on studies that were conducted previously.

  19. Lightweight cryptography for constrained devices

    DEFF Research Database (Denmark)

    Alippi, Cesare; Bogdanov, Andrey; Regazzoni, Francesco

    2014-01-01

    Lightweight cryptography is a rapidly evolving research field that responds to the request for security in resource constrained devices. This need arises from crucial pervasive IT applications, such as those based on RFID tags where cost and energy constraints drastically limit the solution...... complexity, with the consequence that traditional cryptography solutions become too costly to be implemented. In this paper, we survey design strategies and techniques suitable for implementing security primitives in constrained devices....

  20. Plastic condoms.

    Science.gov (United States)

    1968-01-01

    Only simple equipment, simple technology and low initial capital investment are needed in their manufacture. The condoms can be made by people who were previously unskilled or only semi-skilled workers. Plastic condoms differ from those made of latex rubber in that the nature of the plastic film allows unlimited shelf-life. Also, the plastic has a higher degree of lubricity than latex rubber; if there is a demand for extra lubrication in a particular market, this can be provided. Because the plastic is inert, these condoms need not be packaged in hermetically sealed containers. All these attributes make it possible to put these condoms on the distributors' shelves in developing countries competitively with rubber condoms. The shape of the plastic condom is based on that of the lamb caecum, which has long been used as luxury-type condom. The plastic condom is made from plastic film (ethylene ethyl acrilate) of 0.001 inch (0.0254 mm.) thickness. In addition, a rubber ring is provided and sealed into the base of the condom for retention during coitus. The advantage of the plastic condom design and the equipment on which it is made is that production can be carried out either in labour-intensive economy or with varying degrees of mechanization and automation. The uniform, finished condom if made using previously untrained workers. Training of workers can be done in a matter of hours on the two machines which are needed to produce and test the condoms. The plastic film is provided on a double wound roll, and condom blanks are prepared by means of a heat-sealing die on the stamping machine. The rubber rings are united to the condom blanks on an assembly machine, which consists of a mandrel and heat-sealing equipment to seal the rubber ring to the base of the condom. Built into the assembly machine is a simple air-testing apparatus that can detect the smallest pinhole flaw in a condom. The manufacturing process is completed by unravelling the condom from the assembly

  1. Lightweight Ultrahigh Temperature CMC-Encased C/C Structure for Reentry and Hypersonic Applications, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Future reentry and hypersonic vehicles require advanced lightweight leading edge thermal protection systems that can provide the dual functionality of...

  2. Development of lightweight THUNDER with fiber composite layers

    Science.gov (United States)

    Yoon, Kwang J.; Shin, Sukjoon; Kim, Jusik; Park, Hoon C.; Kwak, Moon K.

    2000-06-01

    This paper is concerned with design, manufacturing and performance test of lightweight THUNDER using a top fiber composite layer with near-zero CTE, a PZT ceramic wafer and a bottom glass/epoxy layer with high CTE. The main point of this design is to replace the heavy metal layers of THUNDER by the lightweight fiber reinforced plastic layers without losing capabilities to generate high force and displacement. It is possible to save weight up to about 30 percent if we replace the metallic backing materials by the light fiber composite layer. We can also have design flexibility by selecting the fiber direction and the size of prepreg layers. In addition to the lightweight advantage and design flexibility, the proposed device can be manufactured without adhesive layers when we use epoxy resin prepreg system. Glass/epoxy prepregs, a ceramic wafer with electrode surfaces, and a graphite/epoxy prepreg were simply stacked and cured at an elevated temperature by following autoclave bagging process. It was found that the manufactured composite laminate device had a sufficient curvature after detaching form a flat mold. From experimental actuation tests, it was observed that the developed actuator could generate larger actuation displacement than THUNDER.

  3. Reinforced plastics and aerogels by nanocrystalline cellulose

    Energy Technology Data Exchange (ETDEWEB)

    Leung, Alfred C. W.; Lam, Edmond; Chong, Jonathan; Hrapovic, Sabahudin; Luong, John H. T., E-mail: john.luong@cnrc-nrc.gc.ca [National Research Council Canada (Canada)

    2013-05-15

    Nanocrystalline cellulose (NCC), a rigid rod-like nanoscale material, can be produced from cellulosic biomass in powder, liquid, or gel forms by acid and chemical hydrolysis. Owing to its unique and exceptional physicochemical properties, the incorporation of a small amount of NCC into plastic enhances the mechanical strength of the latter by several orders of magnitudes. Carbohydrate-based NCC poses no serious environmental concerns, providing further impetus for the development and applications of this green and renewable biomaterial to fabricate lightweight and biodegradable composites and aerogels. Surface functionalization of NCC remains the main focus of NCC research to tailor its properties for dispersion in hydrophilic or hydrophobic media. It is of uttermost importance to develop tools and protocols for imaging of NCC in a complex matrix and quantify its reinforcement effect.

  4. Lightweight armor system

    Science.gov (United States)

    Chu, Henry S; Langhorst, Benjamin R; Bakas, Michael P; Thinnes, Gary L

    2013-02-26

    The disclosure provides a shock absorbing layer comprised of one or more shock absorbing cells, where a shock absorbing cell is comprised of a cell interior volume containing a plurality of hydrogel particles and a free volume, and where the cell interior volume is surrounded by a containing layer. The containing layer has a permeability such that the hydrogel particles when swollen remain at least partially within the cell interior volume when subjected to a design shock pressure wave, allowing for force relaxation through hydrogel compression response. Additionally, the permeability allows for the flow of exuded free water, further dissipating wave energy. In an embodiment, a plurality of shock absorbing cells is combined with a penetration resistant material to mitigate the transmitted shock wave generated by an elastic precursor wave in the penetration resistant material.

  5. Advanced lightweight optics development for space applications

    International Nuclear Information System (INIS)

    Bilbro, James W.

    1998-01-01

    A considerable amount of effort over the past year has been devoted to exploring ultra-lightweight optics for two specific NASA programs, the Next Generation Space Telescope (NGST), and the High Throughput X-ray Spectrometer (HTXS). Experimental investigations have been undertaken in a variety of materials including glass, composites, nickel, beryllium, Carbon fiber reinforced Silicon Carbide (CSiC), Reaction Bonded Silicon Carbide, Chemical Vapor Deposited Silicon Carbide, and Silicon. Overall results of these investigations will be summarized, and specific details will be provided concerning the in-house development of ultra-lightweight nickel replication for both grazing incidence and normal incidence optics. This will include x-ray test results of the grazing incidence optic and cryogenic test results of the normal incidence optic. The status of two 1.5 meter diameter demonstration mirrors for NGST will also be presented. These two demonstrations are aimed at establishing the capability to manufacture and test mirrors that have an areal density of 15 kilograms per square meter. Efforts in thin membrane mirrors and Fresnel lenses will also be briefly discussed

  6. Properties of lightweight aggregate concrete prepared with PVC granules derived from scraped PVC pipes.

    Science.gov (United States)

    Kou, S C; Lee, G; Poon, C S; Lai, W L

    2009-02-01

    This paper aims to investigate the fresh and hardened properties of lightweight aggregate concretes that are prepared with the use of recycled plastic waste sourced from scraped PVC pipes to replace river sand as fine aggregates. A number of laboratory prepared concrete mixes were tested, in which river sand was partially replaced by PVC plastic waste granules in percentages of 0%, 5%, 15%, 30% and 45% by volume. Two major findings are identified. The positive side shows that the concrete prepared with a partial replacement by PVC was lighter (lower density), was more ductile (greater Poisson's ratios and reduced modulus of elasticity), and had lower drying shrinkage and higher resistance to chloride ion penetration. The negative side reveals that the workability, compressive strength and tensile splitting strength of the concretes were reduced. The results gathered would form a part of useful information for recycling PVC plastic waste in lightweight concrete mixes.

  7. HOKES/POKES : Light-weight resource sharing

    NARCIS (Netherlands)

    Bos, Herbert; Samwel, Bart

    2003-01-01

    In this paper, we explain mechanisms for providing embedded network processors and other low-level programming environments with light-weight support for safe resource sharing. The solution consists of a host part, known as HOKES, and a network processor part, known as POKES. As common operating

  8. Vibrations in a Multi-Storey Lightweight Building Structure

    DEFF Research Database (Denmark)

    Andersen, Lars Vabbersgaard; Kirkegaard, Poul Henning

    2013-01-01

    This paper provides a quantification of the changes in vibration level that can be expected in a lightweight multi-storey wooden building due to reduced connection stiffness or added nonstructural mass. Firstly, the impact of changes in the floor-to-wall connections is examined. Secondly, a study...

  9. Sequence analysis of the PIP5K locus in Eimeria maxima provides further evidence for eimerian genome plasticity and segmental organization.

    Science.gov (United States)

    Song, B K; Pan, M Z; Lau, Y L; Wan, K L

    2014-07-29

    Commercial flocks infected by Eimeria species parasites, including Eimeria maxima, have an increased risk of developing clinical or subclinical coccidiosis; an intestinal enteritis associated with increased mortality rates in poultry. Currently, infection control is largely based on chemotherapy or live vaccines; however, drug resistance is common and vaccines are relatively expensive. The development of new cost-effective intervention measures will benefit from unraveling the complex genetic mechanisms that underlie host-parasite interactions, including the identification and characterization of genes encoding proteins such as phosphatidylinositol 4-phosphate 5-kinase (PIP5K). We previously identified a PIP5K coding sequence within the E. maxima genome. In this study, we analyzed two bacterial artificial chromosome clones presenting a ~145-kb E. maxima (Weybridge strain) genomic region spanning the PIP5K gene locus. Sequence analysis revealed that ~95% of the simple sequence repeats detected were located within regions comparable to the previously described feature-rich segments of the Eimeria tenella genome. Comparative sequence analysis with the orthologous E. maxima (Houghton strain) region revealed a moderate level of conserved synteny. Unique segmental organizations and telomere-like repeats were also observed in both genomes. A number of incomplete transposable elements were detected and further scrutiny of these elements in both orthologous segments revealed interesting nesting events, which may play a role in facilitating genome plasticity in E. maxima. The current analysis provides more detailed information about the genome organization of E. maxima and may help to reveal genotypic differences that are important for expression of traits related to pathogenicity and virulence.

  10. Experimental research on reinforced lightweight plugging composites.

    Directory of Open Access Journals (Sweden)

    BEKBAEV Arstan Abaevich

    2017-08-01

    Full Text Available Practical aspects of the well construction show that the use of conventional cementing materials do not always provide the necessary level of quality of well casing when the requirements to resources conservation are enhanced. This is true for such complex geological conditions as the alternation of beds with different formation pressures, low fracturing pressure gradients, drilling with ERD tc. The main problems in well casing under these conditions are the losses of cement slurries, low cement top, low-quality formation isolation, and as the result of this – the emergence of cross-flows. The high quality of well casing will be provided only by means of safe contact between cement stone and limiting surfaces (casing and rock, therefore to use expansion materials for cementing is a well-recognized method. Thus, it is obvious that their application does not give positive results for intervals with a thick filter cake or intervals with cavities, i.e. where space for expansion is greater than the magnitude of the expansion. At the same time it is very challenging to create high-quality cement in formations with abnormally low formation pressure or low fracture gradient. The solution of this problem is the use of lightweight cements, which scarcely expand while hardening. This is due to the fact that lightweight cement slurries are generally obtained by increasing the content of grouting fluid in the solution, resulting in increase of the distance between the crystal hydrates – hardening products, that leads to decrease of crystallization pressure of expansion agents on the space frame of the cement stone]. Moreover, such works as secondary reservoir developing (perforation, well completion and fracturing operations create high dynamic load on the cement stone, which leads to its destruction. The stone can be completely destroyed, that often causes premature flooding of wells and incurring additional costs. In this regard, it is necessary to

  11. Plastic Surgery

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Plastic Surgery KidsHealth / For Teens / Plastic Surgery What's in ... her forehead lightened with a laser? What Is Plastic Surgery? Just because the name includes the word " ...

  12. Protect sensitive data with lightweight memory encryption

    Science.gov (United States)

    Zhou, Hongwei; Yuan, Jinhui; Xiao, Rui; Zhang, Kai; Sun, Jingyao

    2018-04-01

    Since current commercial processor is not able to deal with the data in the cipher text, the sensitive data have to be exposed in the memory. It leaves a window for the adversary. To protect the sensitive data, a direct idea is to encrypt the data when the processor does not access them. On the observation, we have developed a lightweight memory encryption, called LeMe, to protect the sensitive data in the application. LeMe marks the sensitive data in the memory with the page table entry, and encrypts the data in their free time. LeMe is built on the Linux with a 3.17.6 kernel, and provides four user interfaces as dynamic link library. Our evaluations show LeMe is effective to protect the sensitive data and incurs an acceptable performance overhead.

  13. Evaluation of a highway bridge constructed using high strength lightweight concrete bridge girders.

    Science.gov (United States)

    2011-04-01

    The use of high performance concretes to provide longer bridge spans has been limited due to the capacity of existing infrastructure to handle the load of the girders during transportation. The use of High Strength Lightweight Concrete (HSLW) can pro...

  14. Load-carrying capacity of lightly reinforced, prefabricated walls of lightweight aggregate concrete with open structure

    DEFF Research Database (Denmark)

    Goltermann, Per

    2009-01-01

    The paper presents and evaluates the results of a coordinated testing of prefabricated, lightly reinforced walls of lightweight aggregate concrete with open structure. The coordinated testing covers all wall productions in Denmark and will therefore provide a representative assessment...

  15. Efficient Lightweight AC-AC Power Control for Solar UAV, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — A highly efficient and lightweight dual bridge matrix power controller development is proposed that will provide high performance to a solar powered high altitude...

  16. Silicon Carbide Lightweight Optics With Hybrid Skins for Large Cryo Telescopes, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Optical Physics Company (OPC) proposes to manufacture new silicon carbide (SiC) foam-based optics that are composite, athermal and lightweight (FOCAL) that provide...

  17. Algorithms for Lightweight Key Exchange.

    Science.gov (United States)

    Alvarez, Rafael; Caballero-Gil, Cándido; Santonja, Juan; Zamora, Antonio

    2017-06-27

    Public-key cryptography is too slow for general purpose encryption, with most applications limiting its use as much as possible. Some secure protocols, especially those that enable forward secrecy, make a much heavier use of public-key cryptography, increasing the demand for lightweight cryptosystems that can be implemented in low powered or mobile devices. This performance requirements are even more significant in critical infrastructure and emergency scenarios where peer-to-peer networks are deployed for increased availability and resiliency. We benchmark several public-key key-exchange algorithms, determining those that are better for the requirements of critical infrastructure and emergency applications and propose a security framework based on these algorithms and study its application to decentralized node or sensor networks.

  18. Handbook of Plastic Welding

    DEFF Research Database (Denmark)

    Islam, Aminul

    The purpose of this document is to summarize the information about the laser welding of plastic. Laser welding is a matured process nevertheless laser welding of micro dimensional plastic parts is still a big challenge. This report collects the latest information about the laser welding of plastic...... materials and provides an extensive knowhow on the industrial plastic welding process. The objectives of the report include: - Provide the general knowhow of laser welding for the beginners - Summarize the state-of-the-art information on the laser welding of plastics - Find the technological limits in terms...... of design, materials and process - Find the best technology, process and machines adaptive to Sonion’s components - Provide the skills to Sonion’s Design Engineers for successful design of the of the plastic components suitable for the laser welding The ultimate goal of this report is to serve...

  19. ANALYSIS OF THE CHARACTERISTICS OF INTERNATIONAL STANDARD ALGORITHMS «LIGHTWEIGHT CRYPTOGRAPHY» – ISO/IEC 29192-3:2012

    Directory of Open Access Journals (Sweden)

    A. S. Poljakov

    2014-01-01

    Full Text Available The data on the characteristics of international standard algorithms «lightweight cryptography» while application in hardware implementation based on microchips of FPGA are provided. A compari-son of the characteristics of these algorithms with the characteristics of several widely-used standard encryption algorithms is made and possibilities of lightweight cryptography algorithms are evaluated.

  20. Thermal properties of light-weight concrete with waste polypropylene aggregate

    Science.gov (United States)

    Záleská, Martina; Pokorný, Jaroslav; Pavlíková, Milena; Pavlík, Zbyšek

    2017-07-01

    Thermal properties of a sustainable light-weight concrete incorporating high volume of waste polypropylene as partial substitution of natural aggregate were studied in the paper. Glass fiber reinforced polypropylene (GFPP), a by-product of PP tubes production, partially substituted fine natural silica aggregate in 10, 20, 30, 40, and 50 mass%. In order to quantify the effect of GFPP use on concrete properties, a reference concrete mix without plastic waste was studied as well. For the applied GFPP, bulk density, matrix density, and particle size distribution were measured. Specific attention was paid to thermal transport and storage properties of GFPP that were examined in dependence on compaction time. For the developed light-weight concrete, thermal properties were accessed using transient impulse technique, whereas the measurement was done in dependence on moisture content, from the dry state to fully water saturated state. Additionally, the investigated thermal properties were plotted as function of porosity. The tested light-weight concrete was found to be prospective construction material possessing improved thermal insulation function. Moreover, the reuse of waste plastics in concrete composition was beneficial both from the environmental and financial point of view considering plastics low biodegradability and safe disposal.

  1. LIGHTWEIGHT CONCRETES WITH FLY–ASH OF PRYDNIPROVSK THERMAL POWER STATION

    Directory of Open Access Journals (Sweden)

    M. I. Netesa

    2013-08-01

    Full Text Available Purpose. Determination of conformities to law of influence of expense of components of easy concretes, which turn out on the basis of local afterproducts of industry, on their basic properties under conditions of enhanceable efficiency of the use of cement. Methodology. Experimental studies on optimization of structures and properties of concrete were carried out with use of mathematical planning experiments methods. All experiments were carried out on orthogonal design with three variables. Cement, water and additives PLKP-2 consumption were taken as varied factors. Findings. Vast experimental studies on determination of rational compositions of concrete mixtures were conducted with the use as fillers of granulated slag from iron and steel plant named after Petrovskiy and Dnepr sand, as binding agent Krivoy Rog portland-cement II/B-Ш-400, as filler fly-ash of Pridneprovsk Thermal Power Station. Efficiency coefficient of cement use was adopted as basic criterion of concrete composition rationality, it is determined on the relation of the attained durability per unit weight of used cement. For greater efficiency coefficient of cement use regularity of rational grain composition of components previously obtained was adopted, it is provided at a ratio of a large fraction consumption to medium and small 52:23:25, and their sizes are approximately 100:10:1. Experimental studies with use of mathematical planning experiments method were carried out. By results of their processing isofields were constructed according to the strength and effectiveness of the use of cement ratio of the studied factors. Originality. By strength comparative tests of hardened concrete with various local secondary resources, modified with complex plasticizer PLKP-2 additive, it was found that lightweight concrete with the density of 1700…1800 kg/m3 and concrete compressive strength from 5 to 20 MPa on the basis of granulated slag from the iron and steel plant named after

  2. High Efficency Lightweight Radiators, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — XC Associates proposes to build on prior work to develop and characterize a very high efficiency, lightweight radiator constructed from high thermal conductivity...

  3. Lightweight Composite Materials for Heavy Duty Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Pruez, Jacky; Shoukry, Samir; Williams, Gergis; Shoukry, Mark

    2013-08-31

    The main objective of this project is to develop, analyze and validate data, methodologies and tools that support widespread applications of automotive lightweighting technologies. Two underlying principles are guiding the research efforts towards this objective: • Seamless integration between the lightweight materials selected for certain vehicle systems, cost-effective methods for their design and manufacturing, and practical means to enhance their durability while reducing their Life-Cycle-Costs (LCC). • Smooth migration of the experience and findings accumulated so far at WVU in the areas of designing with lightweight materials, innovative joining concepts and durability predictions, from applications to the area of weight savings for heavy vehicle systems and hydrogen storage tanks, to lightweighting applications of selected systems or assemblies in light–duty vehicles.

  4. Volume changes in unrestrained structural lightweight concrete.

    Science.gov (United States)

    1964-08-01

    In this study a comparator-type measuring system was developed to accurately determine volume change characteristics of one structural lightweight concrete. The specific properties studied were the coefficient of linear thermal expansion and unrestra...

  5. 3D-printed lightweight drones

    DEFF Research Database (Denmark)

    Geiger, Raphael

    2018-01-01

    New Materials within additive manufacturing offer new potentials for drone production - especially in lightweight design. Flying drones benefit significantly from this developments. In regards to quality assurance the technical challenge is to offer a complete quality control within production. T...

  6. Titanium Nanocomposite: Lightweight Multifunction Structural Material

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to research and develop lightweight metal matrix nanocomposites (MMnC) using a Titanium (Ti) metal matrix. Ti MMnC will crosscut the advancement of both...

  7. Caspase-9 mediates synaptic plasticity and memory deficits of Danish dementia knock-in mice: caspase-9 inhibition provides therapeutic protection

    Directory of Open Access Journals (Sweden)

    Tamayev Robert

    2012-12-01

    Full Text Available Abstract Background Mutations in either Aβ Precursor protein (APP or genes that regulate APP processing, such as BRI2/ITM2B and PSEN1/PSEN2, cause familial dementias. Although dementias due to APP/PSEN1/PSEN2 mutations are classified as familial Alzheimer disease (FAD and those due to mutations in BRI2/ITM2B as British and Danish dementias (FBD, FDD, data suggest that these diseases have a common pathogenesis involving toxic APP metabolites. It was previously shown that FAD mutations in APP and PSENs promote activation of caspases leading to the hypothesis that aberrant caspase activation could participate in AD pathogenesis. Results Here, we tested whether a similar mechanism applies to the Danish BRI2/ITM2B mutation. We have generated a genetically congruous mouse model of FDD, called FDDKI, which presents memory and synaptic plasticity deficits. We found that caspase-9 is activated in hippocampal synaptic fractions of FDDKI mice and inhibition of caspase-9 activity rescues both synaptic plasticity and memory deficits. Conclusion These data directly implicate caspase-9 in the pathogenesis of Danish dementia and suggest that reducing caspase-9 activity is a valid therapeutic approach to treating human dementias.

  8. The existing situation and challenges regarding the use of plastic carrier bags in Europe.

    Science.gov (United States)

    Kasidoni, Maria; Moustakas, Konstantinos; Malamis, Dimitris

    2015-05-01

    Since day one, retailers and consumers have favoured plastic carrier bags. However, owing to the numerous environmental disadvantages, lightweight plastic carrier bags have been drawing the attention of the European Union competent authorities. Therefore, many European Union member states have taken action so as to reduce the use of plastic carrier bags. Based on the existing legislation and voluntary initiatives for the reduction of lightweight plastic carrier bags, the challenges and achieved outcomes from the implemented policy options in the various European Union member states are discussed and commented regarding the forthcoming transposition of the 'Directive 94/62/EC on packaging and packaging waste to reduce the consumption of lightweight plastic carrier bags' into the European Union member states' national law. © The Author(s) 2015.

  9. Light-weight radioisotope heater impact tests

    International Nuclear Information System (INIS)

    Reimus, M.A.H.; Rinehart, G.H.; Herrera, A.

    1998-01-01

    The light-weight radioisotope heater unit (LWRHU) is a 238 PuO 2 -fueled heat source designed to provide one thermal watt in each of various locations on a spacecraft. Los Alamos National Laboratory designed, fabricated, and safety tested the LWRHU. The heat source consists of a hot-pressed 238 PuO 2 fuel pellet, a Pt-30Rh vented capsule, a pyrolytic graphite insulator, and a fineweave-pierced fabric graphite aeroshell assembly. To compare the performance of the LWRHUs fabricated for the Cassini mission with the performance of those fabricated for the Galileo mission, and to determine a failure threshold, two types of impact tests were conducted. A post-reentry impact test was performed on one of 180 flight-quality units produced for the Cassini mission and a series of sequential impact tests using simulant-fueled LWRHU capsules were conducted respectively. The results showed that deformation and fuel containment of the impacted Cassini LWRHU was similar to that of a previously tested Galileo LWRHU. Both units sustained minimal deformation of the aeroshell and fueled capsule; the fuel was entirely contained by the platinum capsule. Sequential impacting, in both end-on and side-on orientations, resulted in increased damage with each subsequent impact. Sequential impacting of the LWRHU appears to result in slightly greater damage than a single impact at the final impact velocity of 50 m/s

  10. Testnodes: a Lightweight node-testing infrastructure

    International Nuclear Information System (INIS)

    Fay, R; Bland, J

    2014-01-01

    A key aspect of ensuring optimum cluster reliability and productivity lies in keeping worker nodes in a healthy state. Testnodes is a lightweight node testing solution developed at Liverpool. While Nagios has been used locally for general monitoring of hosts and services, Testnodes is optimised to answer one question: is there any reason this node should not be accepting jobs? This tight focus enables Testnodes to inspect nodes frequently with minimal impact and provide a comprehensive and easily extended check with each inspection. On the server side, Testnodes, implemented in python, interoperates with the Torque batch server to control the nodes production status. Testnodes remotely and in parallel executes client-side test scripts and processes the return codes and output, adjusting the node's online/offline status accordingly to preserve the integrity of the overall batch system. Testnodes reports via log, email and Nagios, allowing a quick overview of node status to be reviewed and specific node issues to be identified and resolved quickly. This presentation will cover testnodes design and implementation, together with the results of its use in production at Liverpool, and future development plans.

  11. Lightweight autonomous chemical identification system (LACIS)

    Science.gov (United States)

    Lozos, George; Lin, Hai; Burch, Timothy

    2012-06-01

    Smiths Detection and Intelligent Optical Systems have developed prototypes for the Lightweight Autonomous Chemical Identification System (LACIS) for the US Department of Homeland Security. LACIS is to be a handheld detection system for Chemical Warfare Agents (CWAs) and Toxic Industrial Chemicals (TICs). LACIS is designed to have a low limit of detection and rapid response time for use by emergency responders and could allow determination of areas having dangerous concentration levels and if protective garments will be required. Procedures for protection of responders from hazardous materials incidents require the use of protective equipment until such time as the hazard can be assessed. Such accurate analysis can accelerate operations and increase effectiveness. LACIS is to be an improved point detector employing novel CBRNE detection modalities that includes a militaryproven ruggedized ion mobility spectrometer (IMS) with an array of electro-resistive sensors to extend the range of chemical threats detected in a single device. It uses a novel sensor data fusion and threat classification architecture to interpret the independent sensor responses and provide robust detection at low levels in complex backgrounds with minimal false alarms. The performance of LACIS prototypes have been characterized in independent third party laboratory tests at the Battelle Memorial Institute (BMI, Columbus, OH) and indoor and outdoor field tests at the Nevada National Security Site (NNSS). LACIS prototypes will be entering operational assessment by key government emergency response groups to determine its capabilities versus requirements.

  12. Mechanical Properties of Fiber Reinforced Lightweight Concrete Containing Surfactant

    Directory of Open Access Journals (Sweden)

    Yoo-Jae Kim

    2010-01-01

    Full Text Available Fiber reinforced aerated lightweight concrete (FALC was developed to reduce concrete's density and to improve its fire resistance, thermal conductivity, and energy absorption. Compression tests were performed to determine basic properties of FALC. The primary independent variables were the types and volume fraction of fibers, and the amount of air in the concrete. Polypropylene and carbon fibers were investigated at 0, 1, 2, 3, and 4% volume ratios. The lightweight aggregate used was made of expanded clay. A self-compaction agent was used to reduce the water-cement ratio and keep good workability. A surfactant was also added to introduce air into the concrete. This study provides basic information regarding the mechanical properties of FALC and compares FALC with fiber reinforced lightweight concrete. The properties investigated include the unit weight, uniaxial compressive strength, modulus of elasticity, and toughness index. Based on the properties, a stress-strain prediction model was proposed. It was demonstrated that the proposed model accurately predicts the stress-strain behavior of FALC.

  13. Broadband low-frequency sound isolation by lightweight adaptive metamaterials

    Science.gov (United States)

    Liao, Yunhong; Chen, Yangyang; Huang, Guoliang; Zhou, Xiaoming

    2018-03-01

    Blocking broadband low-frequency airborne noises is highly desirable in lots of engineering applications, while it is extremely difficult to be realized with lightweight materials and/or structures. Recently, a new class of lightweight adaptive metamaterials with hybrid shunting circuits has been proposed, demonstrating super broadband structure-borne bandgaps. In this study, we aim at examining their potentials in broadband sound isolation by establishing an analytical model that rigorously combines the piezoelectric dynamic couplings between adaptive metamaterials and acoustics. Sound transmission loss of the adaptive metamaterial is investigated with respect to both the frequency and angular spectrum to demonstrate their sound-insulation effects. We find that efficient sound isolation can indeed be pursued in the broadband bi-spectrum for not only the case of the small resonator's periodicity where only one mode relevant to the mass-spring resonance exists, but also for the large-periodicity scenario, so that the total weight can be even lighter, in which the multiple plate-resonator coupling modes appear. In the latter case, the negative spring stiffness provided by the piezoelectric stack has been utilized to suppress the resonance-induced high acoustic transmission. Such kinds of adaptive metamaterials could open a new approach for broadband noise isolation with extremely lightweight structures.

  14. A comparison of dose savings of lead and lightweight aprons for shielding of 99m-Technetium radiation

    International Nuclear Information System (INIS)

    Warren-Forward, H.; Cardew, P.; Smith, B.; Clack, L.; McWhirter, K.; Johnson, S.; Wessel, K.

    2007-01-01

    Nuclear medicine technologists (NMTs) have the highest effective doses of radiation among medical workers. With increase in the use of lightweight materials in diagnostic radiography, the aim was to compare the effectiveness of lead and lightweight aprons in shielding from 99m-Technetium ( 99m Tc) gamma rays. The doses received from a scattering phantom to the entrance, 9 cm depth and exit of a phantom were measured with LiF:Mg, Cu, P thermoluminescent dosemeters (TLDs). Doses and spectra were assessed without no shielding, with 0.5-mm lead and lightweight aprons. The lead and lightweight aprons decreased entrance surface doses by 76 and 59%, respectively. The spectral analysis showed that the lightweight apron provided better dose reduction at energies 99m Tc labelled radiopharmaceutical. (authors)

  15. Geopolymerization of lightweight aggregate waste

    Directory of Open Access Journals (Sweden)

    Labrincha, J. A.

    2008-09-01

    Full Text Available Geopolymerization is a viable way to process and re-use alumino-silicate industrial waste while producing highstrength, high chemical inertia materials that can effectively immobilize other industrial by-products, and even hazardous waste. In this study industrial waste from different stages of the manufacture of lightweight expanded clay aggregate was characterized for its possible transformation, via alkali activation, to geopolymers. The ultimate aim was to assess the possibility of using such geopolymers to develop thermal and acoustic insulation panels. The containment of hazardous materials is another important application for these new materials. Geopolymers were prepared for this study with different particles size distributions and activator concentrations. Their mechanical properties, composition and microstructure were characterized and a material with promising insulating properties was produced. A preliminary analysis was conducted of the salt formation observed in these geopolymers, the chief drawback to their use.La geopolimerización es una manera viable para procesar y agregar valor a los residuos industriales de alumino-silicato dando lugar a materiales con elevadas resistencias mecánmicas, alta inercia química y que permiten encapsular otros residuos, incluso peligrosos. Los residuos industriales que proceden de diversos tipos de arcillas para la fabricación de áridos ligeros se han caracterizado para la producción de geopolímeros mediante el proceso de ataque alcalino. Su incorporación en una matriz geopolimérica permite la posibilidad de desarrollo de paneles de aislamiento (térmico y acústico. Además, la inmovilización de materiales peligrosos es un logro adicional importante. Los geopolímeros se han producido con fórmulas diferentes y se han caracterizado sus propiedades mecánicas, composición y microestructura, para dar lugar a una composición interesante con propiedades aislantes. Se ha llevado a cabo

  16. Infinte Periodic Structure of Lightweight Elements

    DEFF Research Database (Denmark)

    Domadiya, Parthkumar Gandalal; Andersen, Lars Vabbersgaard; Sorokin, Sergey

    2013-01-01

    Lightweight wooden structures have become more popular as a sustainable, environmental- friendly and cost-effective alternative to concrete, steel and masonry buildings. However, there are certain drawbacks regarding noise and vibration due to the smaller weight and stiffness of wooden buildings....... Furthermore, lightweight building elements are typically periodic structures that behave as filters for sound propagation within certain frequency ranges (stop bands), thus only allowing transmission within the pass bands. Hence, traditional methods based on statistical energy analysis cannot be used...... for proper dynamic assessment of lightweight buildings. Instead, this paper discusses and compares the use of finite element analysis and a wave approach based on Floquet theory. The present analysis has focus on the effect of periodicity on vibration transmission within semi-infinite beam structures. Two...

  17. Application of Glass Fiber Waste Polypropylene Aggregate in Lightweight Concrete – thermal properties

    Science.gov (United States)

    Citek, D.; Rehacek, S.; Pavlik, Z.; Kolisko, J.; Dobias, D.; Pavlikova, M.

    2018-03-01

    Actual paper focus on thermal properties of a sustainable lightweight concrete incorporating high volume of waste polypropylene aggregate as partial substitution of natural aggregate. In presented experiments a glass fiber reinforced polypropylene (GFPP) which is a by-product of PP tubes production, partially substituted fine natural silica aggregate in 10, 20, 30, 40 and 50 mass %. Results were compared with a reference concrete mix without plastic waste in order to quantify the effect of GFPP use on concrete properties. Main material physical parameters were studied (bulk density, matrix density without air content, and particle size distribution). Especially a thermal transport and storage properties of GFPP were examined in dependence on compaction time. For the developed lightweight concrete, thermal properties were accessed using transient impulse technique, where the measurement was done in dependence on moisture content (from the fully water saturated state to dry state). It was found that the tested lightweight concrete should be prospective construction material possessing improved thermal insulation function and the reuse of waste plastics in concrete composition was beneficial both from the environmental and financial point of view.

  18. A MAC Mode for Lightweight Block Ciphers

    DEFF Research Database (Denmark)

    Luykx, Atul; Preneel, Bart; Tischhauser, Elmar Wolfgang

    2016-01-01

    Lightweight cryptography strives to protect communication in constrained environments without sacrificing security. However, security often conflicts with efficiency, shown by the fact that many new lightweight block cipher designs have block sizes as low as 64 or 32 bits. Such low block sizes lead...... no effect on the security bound, allowing an order of magnitude more data to be processed per key. Furthermore, LightMAC is incredibly simple, has almost no overhead over the block cipher, and is parallelizable. As a result, LightMAC not only offers compact authentication for resource-constrained platforms...

  19. Cases of Lightweight Structures for Polar Areas

    DEFF Research Database (Denmark)

    Pedreros, Jessica Fernandoy; Christ, Julian; Shepherd, Paul

    2017-01-01

    The paper focuses on what the authors call ‘Polar Lightweight Structures’. The first part presents a collection of lightweight structures (LWS) designed and built for Antarctic conditions, with the aim of demonstrating the diversity of approaches attempted by designers. The second part of the paper...... presents two studies where different computational methods were applied for the design of generic LWS based on the local conditions of two particular Polar locations; namely, the Arctic region and Glacier Union in the Antarctic plateau. Both studies were conducted independently with the aim...

  20. Environmental assessment of lightweight electric vehicles

    CERN Document Server

    Egede, Patricia

    2017-01-01

    This monograph adresses the challenge of the environmental assessment of leightweight electric vehicles. It poses the question whether the use of lightweight materials in electric vehicles can reduce the vehicles’ environmental impact and compares the environmental performance of a lightweight electric vehicle (LEV) to other types of vehicles. The topical approach focuses on methods from life cycle assessment (LCA), and the book concludes with a comprehensive concept on the environmental assessment of LEVs. The target audience primarily comprises LCA practitioners from research institutes and industry, but it may also be beneficial for graduate students specializing in the field of environmental assessment.

  1. Southern Regional Center for Lightweight Innovative Design

    Energy Technology Data Exchange (ETDEWEB)

    Horstemeyer, Mark F. [Mississippi State Univ., Mississippi State, MS (United States); Wang, Paul [Mississippi State Univ., Mississippi State, MS (United States)

    2011-12-27

    The three major objectives of this Phase III project are: To develop experimentally validated cradle-to-grave modeling and simulation tools to optimize automotive and truck components for lightweighting materials (aluminum, steel, and Mg alloys and polymer-based composites) with consideration of uncertainty to decrease weight and cost, yet increase the performance and safety in impact scenarios; To develop multiscale computational models that quantify microstructure-property relations by evaluating various length scales, from the atomic through component levels, for each step of the manufacturing process for vehicles; and To develop an integrated K-12 educational program to educate students on lightweighting designs and impact scenarios.

  2. Lightweight Ultrahigh Temperature CMC-Encased C/C Structure for Reentry and Hypersonic Applications, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The reentry spacecraft and hypersonic cruisers of the future will require advanced lightweight thermal protection systems that can provide the dual functionality of...

  3. Pavement evaluation using a portable lightweight deflectometer.

    Science.gov (United States)

    2012-12-01

    The use of Zorn ZFG-3000 portable Lightweight Deflectometer (LWD) in the in-situ : assessment of pavement quality was investigated in this research. A lower load and a : shorter load pulse duration are used in a LWD as compared to a Falling Weight : ...

  4. Compact, Lightweight Servo-Controllable Brakes

    Science.gov (United States)

    Lovchik, Christopher S.; Townsend, William; Guertin, Jeffrey; Matsuoka, Yoky

    2010-01-01

    Compact, lightweight servo-controllable brakes capable of high torques are being developed for incorporation into robot joints. A brake of this type is based partly on the capstan effect of tension elements. In a brake of the type under development, a controllable intermediate state of torque is reached through on/off switching at a high frequency.

  5. Individual differences in behavioural plasticities.

    Science.gov (United States)

    Stamps, Judy A

    2016-05-01

    Interest in individual differences in animal behavioural plasticities has surged in recent years, but research in this area has been hampered by semantic confusion as different investigators use the same terms (e.g. plasticity, flexibility, responsiveness) to refer to different phenomena. The first goal of this review is to suggest a framework for categorizing the many different types of behavioural plasticities, describe examples of each, and indicate why using reversibility as a criterion for categorizing behavioural plasticities is problematic. This framework is then used to address a number of timely questions about individual differences in behavioural plasticities. One set of questions concerns the experimental designs that can be used to study individual differences in various types of behavioural plasticities. Although within-individual designs are the default option for empirical studies of many types of behavioural plasticities, in some situations (e.g. when experience at an early age affects the behaviour expressed at subsequent ages), 'replicate individual' designs can provide useful insights into individual differences in behavioural plasticities. To date, researchers using within-individual and replicate individual designs have documented individual differences in all of the major categories of behavioural plasticities described herein. Another important question is whether and how different types of behavioural plasticities are related to one another. Currently there is empirical evidence that many behavioural plasticities [e.g. contextual plasticity, learning rates, IIV (intra-individual variability), endogenous plasticities, ontogenetic plasticities) can themselves vary as a function of experiences earlier in life, that is, many types of behavioural plasticity are themselves developmentally plastic. These findings support the assumption that differences among individuals in prior experiences may contribute to individual differences in behavioural

  6. Saint: a lightweight integration environment for model annotation.

    Science.gov (United States)

    Lister, Allyson L; Pocock, Matthew; Taschuk, Morgan; Wipat, Anil

    2009-11-15

    Saint is a web application which provides a lightweight annotation integration environment for quantitative biological models. The system enables modellers to rapidly mark up models with biological information derived from a range of data sources. Saint is freely available for use on the web at http://www.cisban.ac.uk/saint. The web application is implemented in Google Web Toolkit and Tomcat, with all major browsers supported. The Java source code is freely available for download at http://saint-annotate.sourceforge.net. The Saint web server requires an installation of libSBML and has been tested on Linux (32-bit Ubuntu 8.10 and 9.04).

  7. Vehicle Lightweighting: 40% and 45% Weight Savings Analysis: Technical Cost Modeling for Vehicle Lightweighting

    Energy Technology Data Exchange (ETDEWEB)

    Mascarin, Anthony [Idaho National Lab. (INL), Idaho Falls, ID (United States); Hannibal, Ted [Idaho National Lab. (INL), Idaho Falls, ID (United States); Raghunathan, Anand [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ivanic, Ziga [Idaho National Lab. (INL), Idaho Falls, ID (United States); Francfort, James [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-04-01

    The U.S. Department of Energy’s Vehicle Technologies Office, Materials area commissioned a study to model and assess manufacturing economics of alternative design and production strategies for a series of lightweight vehicle concepts. The strategic targets were a 40% and a 45% mass reduction relative to a standard North American midsize passenger sedan at an effective cost of $3.42 per pound (lb) saved. The baseline vehicle was an average of several available vehicles in this class. Mass and cost breakdowns from several sources were used, including original equipment manufacturers’ (OEMs’) input through U.S. Department of Energy’s Vehicle Technologies Office programs and public presentations, A2Mac1 LLC’s teardown information, Lotus Engineering Limited and FEV, Inc. breakdowns in their respective lightweighting studies, and IBIS Associates, Inc.’s decades of experience in automotive lightweighting and materials substitution analyses. Information on lightweighting strategies in this analysis came from these same sources and the ongoing U.S. Department of Energy-funded Vehma International of America, Inc. /Ford Motor Company Multi-Material Lightweight Prototype Vehicle Demonstration Project, the Aluminum Association Transportation Group, and many United States Council for Automotive Research’s/United States Automotive Materials Partnership LLC lightweight materials programs.

  8. Plastic, Fantastic? What We Make. Science and Technology Education in Philippine Society.

    Science.gov (United States)

    Philippines Univ., Quezon City. Inst. for Science and Mathematics Education Development.

    This module provides information about plastics, focusing on the uses of plastic bags in particular. Topic areas considered include: (1) making plastic bags; (2) transparency of plastic bags; (3) plastic bags and food odors; (4) food containers (before and since plastics); and (5) disposing of plastic bags and other plastic products. The text is…

  9. Plastic dosimeter

    International Nuclear Information System (INIS)

    Nagai, Shiro; Matsuda, Kohji.

    1988-01-01

    The report outlines major features and applications of plastic dosimeters. Some plastic dosimeters, including the CTA and PVC types, detect the response of the plastic material itself to radiations while others, such as pigment-added plastic dosimeters, contain additives as radiation detecting material. Most of these dosimeters make use of color centers produced in the dosimeter by radiations. The PMMA dosimeter is widely used in the field of radiation sterilization of food, feed and medical apparatus. The blue cellophane dosimeter is easy to handle if calibrated appropriately. The rad-color dosimeter serves to determine whether products have been irradiated appropriately. The CTA dosimeter has better damp proofing properties than the blue cellophane type. The pigment-added plastic dosimeter consists of a resin such as nylon, CTA or PVC that contains a dye. Some other plastic dosimeters are also described briefly. Though having many advantages, these plastic dosimeter have disadvantages as well. Some of their major disadvantages, including fading as well as large dependence on dose, temperature, humidity and anviroment, are discussed. (Nogami, K.)

  10. Design and Experimental Verification of Deployable/Inflatable Ultra-Lightweight Structures

    Science.gov (United States)

    Pai, P. Frank

    2004-01-01

    Because launch cost of a space structural system is often proportional to the launch volume and mass and there is no significant gravity in space, NASA's space exploration programs and various science missions have stimulated extensive use of ultra-lightweight deployable/inflatable structures. These structures are named here as Highly Flexible Structures (HFSs) because they are designed to undergo large displacements, rotations, and/or buckling without plastic deformation under normal operation conditions. Except recent applications to space structural systems, HFSs have been used in many mechanical systems, civil structures, aerospace vehicles, home appliances, and medical devices to satisfy space limitations, provide special mechanisms, and/or reduce structural weight. The extensive use of HFSs in today's structural engineering reveals the need of a design and analysis software and a database system with design guidelines for practicing engineers to perform computer-aided design and rapid prototyping of HFSs. Also to prepare engineering students for future structural engineering requires a new and easy-to- understand method of presenting the complex mathematics of the modeling and analysis of HFSs. However, because of the high flexibility of HFSs, many unique challenging problems in the modeling, design and analysis of HFSs need to be studied. The current state of research on HFSs needs advances in the following areas: (1) modeling of large rotations using appropriate strain measures, (2) modeling of cross-section warpings of structures, (3) how to account for both large rotations and cross- section warpings in 2D (two-dimensional) and 1D structural theories, (4) modeling of thickness thinning of membranes due to inflation pressure, pretension, and temperature change, (5) prediction of inflated shapes and wrinkles of inflatable structures, (6) development of efficient numerical methods for nonlinear static and dynamic analyses, and (7) filling the gap between

  11. Nacre-nanomimetics: Strong, Stiff, and Plastic.

    Science.gov (United States)

    De Luca, Francois; Menzel, Robert; Blaker, Jonny J; Birkbeck, John; Bismarck, Alexander; Shaffer, Milo S P

    2015-12-09

    The bricks and mortar in the classic structure of nacre have characteristic geometry, aspect ratios and relative proportions; these key parameters can be retained while scaling down the absolute length scale by more than 1 order of magnitude. The results shed light on fundamental scaling behavior and provide new opportunities for high performance, yet ductile, lightweight nanocomposites. Reproducing the toughening mechanisms of nacre at smaller length scales allows a greater volume of interface per unit volume while simultaneously increasing the intrinsic properties of the inorganic constituents. Layer-by-layer (LbL) assembly of poly(sodium 4-styrenesulfonate) (PSS) polyelectrolyte and well-defined [Mg2Al(OH)6]CO3.nH2O layered double hydroxide (LDH) platelets produces a dense, oriented, high inorganic content (∼90 wt %) nanostructure resembling natural nacre, but at a shorter length scale. The smaller building blocks enable the (self-) assembly of a higher quality nanostructure than conventional mimics, leading to improved mechanical properties, matching those of natural nacre, while allowing for substantial plastic deformation. Both strain hardening and crack deflection mechanisms were observed in situ by scanning electron microscopy (SEM) during nanoindentation. The best properties emerge from an ordered nanostructure, generated using regular platelets, with narrow size dispersion.

  12. Lightweight storage and overlay networks for fault tolerance.

    Energy Technology Data Exchange (ETDEWEB)

    Oldfield, Ron A.

    2010-01-01

    The next generation of capability-class, massively parallel processing (MPP) systems is expected to have hundreds of thousands to millions of processors, In such environments, it is critical to have fault-tolerance mechanisms, including checkpoint/restart, that scale with the size of applications and the percentage of the system on which the applications execute. For application-driven, periodic checkpoint operations, the state-of-the-art does not provide a scalable solution. For example, on today's massive-scale systems that execute applications which consume most of the memory of the employed compute nodes, checkpoint operations generate I/O that consumes nearly 80% of the total I/O usage. Motivated by this observation, this project aims to improve I/O performance for application-directed checkpoints through the use of lightweight storage architectures and overlay networks. Lightweight storage provide direct access to underlying storage devices. Overlay networks provide caching and processing capabilities in the compute-node fabric. The combination has potential to signifcantly reduce I/O overhead for large-scale applications. This report describes our combined efforts to model and understand overheads for application-directed checkpoints, as well as implementation and performance analysis of a checkpoint service that uses available compute nodes as a network cache for checkpoint operations.

  13. Research on carbon fiber–reinforced plastic bumper beam subjected to low-velocity frontal impact

    OpenAIRE

    Yefa Hu; Can Liu; Jinguang Zhang; Guoping Ding; Qiong Wu

    2015-01-01

    Lightweight and safety performance of automobiles are two important factors for automobile designs. In this article, a research on lightweight and crashworthiness of automotive bumper has been conducted. The carbon fiber–reinforced plastic bumper beam is considered to replace the traditional high-strength steel one. The low-velocity impact finite element simulations for the above two bumper beams are performed via LS-DYNA. Furthermore, the energy absorption capabilities and dynamic response c...

  14. PLASTIC SURGERY

    African Journals Online (AJOL)

    Department of Plastic and Reconstructive Surgery Sefako Makgatho Health Science University, ... We report on a pilot study on the use of a circumareolar excision and the use of .... and 1 gynecomastia patient) requested reduction in NAC size.

  15. Plastic Fishes

    CERN Multimedia

    Trettnak, Wolfgang

    2015-01-01

    In terms of weight, the plastic pollution in the world’s oceans is estimated to be around 300,000 tonnes. This plastic comes from both land-based and ocean-based sources. A lecture at CERN by chemist Wolfgang Trettnak addressed this issue and highlighted the role of art in raising people’s awareness. The slideshow below gives you a taste of the artworks by Wolfgang Trettnak and Margarita Cimadevila.

  16. New perspectives in plastic biodegradation.

    Science.gov (United States)

    Sivan, Alex

    2011-06-01

    During the past 50 years new plastic materials, in various applications, have gradually replaced the traditional metal, wood, leather materials. Ironically, the most preferred property of plastics--durability--exerts also the major environmental threat. Recycling has practically failed to provide a safe solution for disposal of plastic waste (only 5% out of 1 trillion plastic bags, annually produced in the US alone, are being recycled). Since the most utilized plastic is polyethylene (PE; ca. 140 million tons/year), any reduction in the accumulation of PE waste alone would have a major impact on the overall reduction of the plastic waste in the environment. Since PE is considered to be practically inert, efforts were made to isolate unique microorganisms capable of utilizing synthetic polymers. Recent data showed that biodegradation of plastic waste with selected microbial strains became a viable solution. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. The use of spent glauconite in lightweight aggregate production

    Directory of Open Access Journals (Sweden)

    Franus, Wojciech

    2011-08-01

    Full Text Available The presented work has shown an application of spent glauconite bed after purification of wastewater for production of lightweight expanded clay aggregates. Sewage, from which it was removed Zn ions, came from technological line (zincworks of Communication Equipment Factory „PZL” Świdnik. Spent glauconite bed was used as an additive in lightweight aggregate production which was obtained using plastic method by sintering, at temperature 1140 ºC and 1200 ºC, of spent glauconite amouts 10, 15, 20 and 25% wt. with clays from open-cast mine „Budy Mszczonowskie”. The presence of the mineral improves sinter texture, increases porosity and contributes to formation of glassy layer on the surface of the aggregates. Tests of zinc elution from lightweight of aggregate samples has shown very low mobility of zinc ions. Content of zinc in water extracts obtained from lightweight of aggregate is definitely lower than zinc concentration permitted for sewage discharge to water or soil, means that spent material is not offensive for the environment as it can be used as a high quality building product.

    El trabajo presentado ha demostrado una aplicación de agotado depósito de glauconita después de la purificación de aguas residuales para la producción de áridos ligeros de arcilla expandida. Las aguas residuales, de la que fueron eliminados los iones Zn, vinieron de la línea tecnológica del equipo de comunicación de la fábrica “PZL” Świdnik. Agotado depósito de glauconita se utiliza como aditivo en la producción de áridos ligeros que se obtuvo utilizando el método de plástico de la sinterización, a temperatura C. 1140 º y 1200 º C, de spent glauconita amouts10, 15, 20 y 25% en peso. con arcillas de la mina a cielo abierto “Budy Mszczonowskie”. La presencia de este mineral mejora la textura de sinterización, aumenta la porosidad y contribuye a la formación de la capa vítrea en la superficie de los agregados. Pruebas de

  18. Data on thermal conductivity, water vapour permeability and water absorption of a cementitious mortar containing end-of-waste plastic aggregates

    OpenAIRE

    Di Maio, Luciano; Coppola, Bartolomeo; Courard, Luc; Michel, Frédéric; Incarnato, Loredana; Scarfato, Paola

    2018-01-01

    The data presented in this article are related to the research article entitled “Hygro-thermal and durability properties of a lightweight mortar made with foamed plastic waste aggregates ” (Coppola et al., 2018). This article focuses the attention on thermal conductivity, water vapour permeability and water absorption of a lightweight cementitious mortar containing foamed end-of-waste plastic aggregates, produced via foam extrusion process. Thermal conductivity, water vapour permeability ...

  19. Portable and Lightweight Ramp Structure

    Science.gov (United States)

    2001-04-09

    long side of which is in abutting relationship with the 12 short side of the end of the ramp. Fastener receivers are equi- 13 spaced in duplicate...The modular sections are conveniently prefabricated 18 1 and provided in kit form to the number of sections corresponding 2 to the desired ramp

  20. UTILIZATION OF LIGHTWEIGHT MATERIALS MADE FROM COAL GASIFICATION SLAGS

    International Nuclear Information System (INIS)

    None

    1998-01-01

    The integrated-gasification combined-cycle (IGCC) process is an emerging technology that utilizes coal for power generation and production of chemical feedstocks. However, the process generates large amounts of solid waste, consisting of vitrified ash (slag) and some unconverted carbon. In previous projects, Praxis investigated the utilization of ''as-generated'' slags for a wide variety of applications in road construction, cement and concrete production, agricultural applications, and as a landfill material. From these studies, we found that it would be extremely difficult for ''as-generated'' slag to find large-scale acceptance in the marketplace even at no cost because the materials it could replace were abundantly available at very low cost. It was further determined that the unconverted carbon, or char, in the slag is detrimental to its utilization as sand or fine aggregate. It became apparent that a more promising approach would be to develop a variety of value-added products from slag that meet specific industry requirements. This approach was made feasible by the discovery that slag undergoes expansion and forms a lightweight material when subjected to controlled heating in a kiln at temperatures between 1400 and 1700 F. These results confirmed the potential for using expanded slag as a substitute for conventional lightweight aggregates (LWA). The technology to produce lightweight and ultra-lightweight aggregates (ULWA) from slag was subsequently developed by Praxis with funding from the Electric Power Research Institute (EPRI), Illinois Clean Coal Institute (ICCI), and internal resources. The major objectives of the subject project are to demonstrate the technical and economic viability of commercial production of LWA and ULWA from slag and to test the suitability of these aggregates for various applications. The project goals are to be accomplished in two phases: Phase I, comprising the production of LWA and ULWA from slag at the large pilot scale, and

  1. Southern Regional Center for Lightweight Innovative Design

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Paul T. [Mississippi State Univ., Mississippi State, MS (United States)

    2012-12-01

    The Southern Regional Center for Lightweight Innovative Design (SRCLID) has developed an experimentally validated cradle-to-grave modeling and simulation effort to optimize automotive components in order to decrease weight and cost, yet increase performance and safety in crash scenarios. In summary, the three major objectives of this project are accomplished: To develop experimentally validated cradle-to-grave modeling and simulation tools to optimize automotive and truck components for lightweighting materials (aluminum, steel, and Mg alloys and polymer-based composites) with consideration of uncertainty to decrease weight and cost, yet increase the performance and safety in impact scenarios; To develop multiscale computational models that quantify microstructure-property relations by evaluating various length scales, from the atomic through component levels, for each step of the manufacturing process for vehicles; and To develop an integrated K-12 educational program to educate students on lightweighting designs and impact scenarios. In this final report, we divided the content into two parts: the first part contains the development of building blocks for the project, including materials and process models, process-structure-property (PSP) relationship, and experimental validation capabilities; the second part presents the demonstration task for Mg front-end work associated with USAMP projects.

  2. Shock Response of Lightweight Adobe Masonry

    Science.gov (United States)

    Sauer, C.; Bagusat, F.; Heine, A.; Riedel, W.

    2018-04-01

    The behavior of a low density and low-strength building material under shock loading is investigated. The considered material is lightweight adobe masonry characterized by a density of 1.2 g/cm3 and a quasi-static uniaxial compressive strength of 2.8 MPa. Planar-plate-impact (PPI) tests with velocities in between 295 and 950 m/s are performed in order to obtain Hugoniot data and to derive parameters for an equation of state (EOS) that captures the occurring phenomenology of porous compaction and subsequent unloading. The resulting EOS description is validated by comparing the experimental free surface velocity time curves with those obtained by numerical simulations of the performed PPI tests. The non-linear compression behavior, including the pore compaction mechanism, constitutes a main ingredient for modelling the response of adobe to blast and high-velocity impact loading. We hence present a modeling approach for lightweight adobe which can be applied to such high rate loading scenarios in future studies. In general, this work shows that PPI tests on lightweight and low-strength geological materials can be used to extract Hugoniot data despite significant material inhomogeneity. Furthermore, we demonstrate that a homogenous material model is able to numerically describe such a material under shock compression and release with a reasonable accuracy.

  3. An Overview of the Effects of Alloying Elements on the Properties of Lightweight Fe-(15-35) Mn-(5-12) Al-(0.3-1.2) C Steel

    Science.gov (United States)

    Xing, Jia; Wei, Yinghui; Hou, Lifeng

    2018-04-01

    In this review, the influences of alloying elements on the phase constitution, density, and stacking fault energy of Fe-(15-35) Mn-(5-12) Al-(0.3-1.2) C lightweight steel are discussed. The mechanical properties of austenite single-phase and austenite-ferrite dual-phase Fe-Mn-Al-C steels processed by different procedures are also statistically analyzed. The austenite single-phase steel was found to possess superior strength and plasticity. Three reasonable explanations for the mechanism of plastic deformation are presented, namely, shear band-induced plasticity, microband-induced plasticity, and slip band refinement-induced plasticity.

  4. GREEN PLASTIC: A NEW PLASTIC FOR PACKAGING

    OpenAIRE

    Mr. Pankaj Kumar*, Sonia

    2016-01-01

    This paper gives a brief idea about a new type of plastic called as bio-plastic or green plastic. Plastic is used as a packaging material for various products, but this plastic is made up of non renewable raw materials. There are various disadvantages of using conventional plastic like littering, CO2 production, non-degradable in nature etc. To overcome these problems a new type of plastic is discovered called bio-plastic or green plastic. Bio-plastic is made from renewable resources and also...

  5. Lightweight, Miniature Inertial Measurement System

    Science.gov (United States)

    Tang, Liang; Crassidis, Agamemnon

    2012-01-01

    A miniature, lighter-weight, and highly accurate inertial navigation system (INS) is coupled with GPS receivers to provide stable and highly accurate positioning, attitude, and inertial measurements while being subjected to highly dynamic maneuvers. In contrast to conventional methods that use extensive, groundbased, real-time tracking and control units that are expensive, large, and require excessive amounts of power to operate, this method focuses on the development of an estimator that makes use of a low-cost, miniature accelerometer array fused with traditional measurement systems and GPS. Through the use of a position tracking estimation algorithm, onboard accelerometers are numerically integrated and transformed using attitude information to obtain an estimate of position in the inertial frame. Position and velocity estimates are subject to drift due to accelerometer sensor bias and high vibration over time, and so require the integration with GPS information using a Kalman filter to provide highly accurate and reliable inertial tracking estimations. The method implemented here uses the local gravitational field vector. Upon determining the location of the local gravitational field vector relative to two consecutive sensors, the orientation of the device may then be estimated, and the attitude determined. Improved attitude estimates further enhance the inertial position estimates. The device can be powered either by batteries, or by the power source onboard its target platforms. A DB9 port provides the I/O to external systems, and the device is designed to be mounted in a waterproof case for all-weather conditions.

  6. Effect of porosity on physical properties of lightweight cement composite with foamed glass aggregate

    Directory of Open Access Journals (Sweden)

    Kurpińska Marzena

    2017-01-01

    Full Text Available This paper reports on a study of physical properties of lightweight cement composite. We investigate the possibility of replacing traditional aggregate with Granulated Ash Aggregate (GAA and above all with Granulated Expanded Glass Aggregate (GEGA. For this purpose, 15 specimens of different percentage share of each aggregate in total aggregate volume were tested: 0%, 25%, 50%, 75% or 100% of foam glass aggregate (GEGA partially replaced by ash aggregate (GAA content in the cement composite. The water-cement ratio was constant and equal to w/c=0.5. Three grain sizes were analyzed: 2mm, 4mm (both GEGA and 8mm (GAA. Numerical simulations of concrete specimen behavior under static loading were conducted with the implementation of elastic plastic model of each component. The study shows a significant impact of grain type and size on physical properties of lightweight concrete. Due to lower density of foamed glass aggregate, specimens shows various apparent density and porosity, which affect concrete properties. Compressive strength of concrete decreases with the increase in foam glass aggregate content; however specimens show different workability and in consequence porosity of lightweight concrete.

  7. Calcined clay lightweight ceramics made with wood sawdust and sodium silicate

    Energy Technology Data Exchange (ETDEWEB)

    Santis, Bruno Carlos de; Rossignolo, Joao Adriano, E-mail: desantis.bruno@gmail.com [Universidade de Sao Paulo (USP), Pirassununga, SP (Brazil); Morelli, Marcio Raymundo [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil). Departamento de Engenharia de Materiais

    2016-11-15

    This paper aims to study the influence of including wood sawdust and sodium silicate in the production process of calcined clay lightweight ceramics. In the production process first, a sample used by a company that produces ceramic products in Brazil was collected. The sample was analysed by techniques of liquidity (LL) and plasticity (LP) limits, particle size analysis, specific mass, X-ray diffraction (XRD) and X ray fluorescence spectrometry (XRF). From the clay, specimens of pure clay and mixtures with wood sawdust (10%, 20% and 30% by mass) and sodium silicate were produced and fired at a temperature of 900 deg C. These specimens were submitted to tests of water absorption, porosity, specific mass and compressive strength. Results of this research indicate that the incorporation of wood sawdust and sodium silicate in the ceramic paste specimens can be useful to make calcined clay lightweight ceramics with special characteristics (low values of water absorption and specific mass and high values of compressive strength), which could be used to produce calcined clay lightweight aggregates to be used in structural concrete. (author)

  8. A novel lightweight Fizeau infrared interferometric imaging system

    Science.gov (United States)

    Hope, Douglas A.; Hart, Michael; Warner, Steve; Durney, Oli; Romeo, Robert

    2016-05-01

    Aperture synthesis imaging techniques using an interferometer provide a means to achieve imagery with spatial resolution equivalent to a conventional filled aperture telescope at a significantly reduced size, weight and cost, an important implication for air- and space-borne persistent observing platforms. These concepts have been realized in SIRII (Space-based IR-imaging interferometer), a new light-weight, compact SWIR and MWIR imaging interferometer designed for space-based surveillance. The sensor design is configured as a six-element Fizeau interferometer; it is scalable, light-weight, and uses structural components and main optics made of carbon fiber replicated polymer (CFRP) that are easy to fabricate and inexpensive. A three-element prototype of the SIRII imager has been constructed. The optics, detectors, and interferometric signal processing principles draw on experience developed in ground-based astronomical applications designed to yield the highest sensitivity and resolution with cost-effective optical solutions. SIRII is being designed for technical intelligence from geo-stationary orbit. It has an instantaneous 6 x 6 mrad FOV and the ability to rapidly scan a 6x6 deg FOV, with a minimal SNR. The interferometric design can be scaled to larger equivalent filled aperture, while minimizing weight and costs when compared to a filled aperture telescope with equivalent resolution. This scalability in SIRII allows it address a range of IR-imaging scenarios.

  9. Coating Thin Mirror Segments for Lightweight X-ray Optics

    Science.gov (United States)

    Chan, Kai-Wing; Sharpe, Marton V.; Zhang, William; Kolosc, Linette; Hong, Melinda; McClelland, Ryan; Hohl, Bruce R.; Saha, Timo; Mazzarellam, James

    2013-01-01

    Next generations lightweight, high resolution, high throughput optics for x-ray astronomy requires integration of very thin mirror segments into a lightweight telescope housing without distortion. Thin glass substrates with linear dimension of 200 mm and thickness as small as 0.4 mm can now be fabricated to a precision of a few arc-seconds for grazing incidence optics. Subsequent implementation requires a distortion-free deposition of metals such as iridium or platinum. These depositions, however, generally have high coating stresses that cause mirror distortion. In this paper, we discuss the coating stress on these thin glass mirrors and the effort to eliminate their induced distortion. It is shown that balancing the coating distortion either by coating films with tensile and compressive stresses, or on both sides of the mirrors is not sufficient. Heating the mirror in a moderately high temperature turns out to relax the coated films reasonably well to a precision of about a second of arc and therefore provide a practical solution to the coating problem.

  10. Lightweight Provenance Service for High-Performance Computing

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Dong; Chen, Yong; Carns, Philip; Jenkins, John; Ross, Robert

    2017-09-09

    Provenance describes detailed information about the history of a piece of data, containing the relationships among elements such as users, processes, jobs, and workflows that contribute to the existence of data. Provenance is key to supporting many data management functionalities that are increasingly important in operations such as identifying data sources, parameters, or assumptions behind a given result; auditing data usage; or understanding details about how inputs are transformed into outputs. Despite its importance, however, provenance support is largely underdeveloped in highly parallel architectures and systems. One major challenge is the demanding requirements of providing provenance service in situ. The need to remain lightweight and to be always on often conflicts with the need to be transparent and offer an accurate catalog of details regarding the applications and systems. To tackle this challenge, we introduce a lightweight provenance service, called LPS, for high-performance computing (HPC) systems. LPS leverages a kernel instrument mechanism to achieve transparency and introduces representative execution and flexible granularity to capture comprehensive provenance with controllable overhead. Extensive evaluations and use cases have confirmed its efficiency and usability. We believe that LPS can be integrated into current and future HPC systems to support a variety of data management needs.

  11. Check of hybrid structures and lightweight construction materials. Usage of 3D-CT

    Energy Technology Data Exchange (ETDEWEB)

    Szepanski, Kamil David [Hachtel Werkzeugbau GmbH und Co.KG, Aalen (Germany)

    2015-07-01

    Lightweight structures and modern methods of generating samples require in most cases non-destructive-testing to verify their state. They often must not be destroyed for initial testing as they are unique and irreplaceable. So computed tomography serves well as the sample is not being touched or manipulated for the analysis. Meanwhile in-situ testing of stable stress situations, for example pressure and tension is available and gives insight where only the measured data were before. This allows the identification of seeds for failure. The production process can be recorded also within the sample and not only its surface. We demonstrate detectable defects in carbon reinforced plastic parts, laser sintered metal parts and an example for optimizing the process of printing a plastic part for function.

  12. Check of hybrid structures and lightweight construction materials. Usage of 3D-CT

    International Nuclear Information System (INIS)

    Szepanski, Kamil David

    2015-01-01

    Lightweight structures and modern methods of generating samples require in most cases non-destructive-testing to verify their state. They often must not be destroyed for initial testing as they are unique and irreplaceable. So computed tomography serves well as the sample is not being touched or manipulated for the analysis. Meanwhile in-situ testing of stable stress situations, for example pressure and tension is available and gives insight where only the measured data were before. This allows the identification of seeds for failure. The production process can be recorded also within the sample and not only its surface. We demonstrate detectable defects in carbon reinforced plastic parts, laser sintered metal parts and an example for optimizing the process of printing a plastic part for function.

  13. Experimental study on microstructure characters of foamed lightweight soil

    Science.gov (United States)

    Qiu, Youqiang; Li, Yongliang; Li, Meixia; Liu, Yaofu; Zhang, Liujun

    2018-01-01

    In order to verify the microstructure of foamed lightweight soil and its characters of compressive strength, four foamed lightweight soil samples with different water-soild ratio were selected and the microstructure characters of these samples were scanned by electron microscope. At the same time, the characters of compressive strength of foamed lightweight soil were analyzed from the microstructure. The study results show that the water-soild ratio has a prominent effect on the microstructure and compressive strength of foamed lightweight soil, with the decrease of water-solid ratio, the amount and the perforation of pores would be reduced significantly, thus eventually forming a denser and fuller interior structure. Besides, the denser microstructure and solider pore-pore wall is benefit to greatly increase mechanical intensity of foamed lightweight soil. In addition, there are very few acicular ettringite crystals in the interior of foamed lightweight soil, its number is also reduced with the decrease in water-soild ratio.

  14. Design of ultra-lightweight concrete: towards monolithic concrete structures

    Directory of Open Access Journals (Sweden)

    Yu Qing Liang

    2014-04-01

    Full Text Available This study addresses the development of ultra-lightweight concrete. A moderate strength and an excellent thermal conductivity of the lightweight concrete are set as the design targets. The designed lightweight aggregates concrete is targeted to be used in monolithic concrete façade structure, performing as both load bearing element and thermal insulator. The developed lightweight concrete shows excellent thermal properties, with a low thermal conductivity of about 0.12 W/(m·K; and moderate mechanical properties, with 28-day compressive strengths of about 10-12 N/mm . This combination of values exceeds, to the researchers’ knowledge, the performance of all other lightweight building materials. Furthermore, the developed lightweight concrete possesses excellent durability properties.

  15. Properties Improvement of Cast Stone Produced Using Recycled Glass Waste and Lightweight Aggregates

    Directory of Open Access Journals (Sweden)

    Elham Abd AL-Majeed

    2018-01-01

    Full Text Available Cast stone (CS is a form of pre-cast concrete widely, used in architectural applications for decorating and building face in place of natural stone due its superior features. The present study was an attempt in using of local lightweight aggregate materials (LWAM as an alternative to percentage of coarse aggregate, and glass wastes as alternatives to percentages of fine aggregate in cast stone normal mixtures with white cement and plasticizer admixture. The CS products were cured after 24 hrs using of two different processes: water curing (at 23 C° for 3 days and steam curing (at 60 C° for 14 hrs. Then the products were characterized by tests of compressive strength, design, absorption, flexure strength and liner drying shrinkage. The addition of alternative materials was done by trial mixes (M0-M3 through 3 groups (A, B, and C according to standards. Group A: design of reference mixtures of CS with compressive strength of 46.3 MPa and the absorption of 6.19%, Group B: design of mixtures containing 50% LWA were 16% lighter than those of Group A with compressive strength of 43.6 MPa and 11% improvement in the absorption, Group C: design of mixtures containing (50 and 75% glass waste with compressive strength of (47.5-44.3 MPa and the absorption of (5.3-4.7%, respectively. The modified steam curing process (curing after 24 hrs casting done in this study could prove its effectiveness in the achievement of the required compressive strength in comparison with the normal process (direct curing after casting due to the effect of such new process in providing the more uniform distribution of the cement gel with good physical properties. Results from the flexural strength test could prove the achievement of the required levels (6.9 – 6.3 at 50 – 75% glass waste addition recorded in the standard.

  16. Magical Engineering Plastic

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Gwang Ung

    1988-01-15

    This book introduces engineering plastic about advantage of engineering plastic, plastic material from processing method, plastic shock, plastic until now, background of making of engineering plastic, wonderful engineering plastic science such as a high molecule and molecule, classification of high molecule, difference between metal and high molecule, heat and high molecule materials, and property of surface, engineering plastic of dream like from linseed oil to aramid, small dictionary of engineering plastic.

  17. Magical Engineering Plastic

    International Nuclear Information System (INIS)

    Kim, Gwang Ung

    1988-01-01

    This book introduces engineering plastic about advantage of engineering plastic, plastic material from processing method, plastic shock, plastic until now, background of making of engineering plastic, wonderful engineering plastic science such as a high molecule and molecule, classification of high molecule, difference between metal and high molecule, heat and high molecule materials, and property of surface, engineering plastic of dream like from linseed oil to aramid, small dictionary of engineering plastic.

  18. Lightweight and Energy Efficient Heat Pump, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Future Spacecraft from the JPL will require increasingly sophisticated thermal control technology. A need exists for efficient, lightweight Vapor Compression Cycle...

  19. Mixed plastics recycling technology

    CERN Document Server

    Hegberg, Bruce

    1995-01-01

    Presents an overview of mixed plastics recycling technology. In addition, it characterizes mixed plastics wastes and describes collection methods, costs, and markets for reprocessed plastics products.

  20. Pervasive plastic

    Science.gov (United States)

    2018-05-01

    Human manipulation of hydrocarbons — as fuel and raw materials for modern society — has changed our world and the indelible imprint we will leave in the rock record. Plastics alone have permeated our lives and every corner of our planet.

  1. Plastic fish

    CERN Multimedia

    Antonella Del Rosso

    2015-01-01

    In terms of weight, the plastic pollution in the world’s oceans is estimated to be around 300,000 tonnes. This plastic comes from both land-based and ocean-based sources. A lecture at CERN by chemist Wolfgang Trettnak addressed this issue and highlighted the role of art in raising people’s awareness.   Artwork by Wolfgang Trettnak. Packaging materials, consumer goods (shoes, kids’ toys, etc.), leftovers from fishing and aquaculture activities… our oceans and beaches are full of plastic litter. Most of the debris from beaches is plastic bottles. “PET bottles have high durability and stability,” explains Wolfgang Trettnak, a chemist by education and artist from Austria, who gave a lecture on this topic organised by the Staff Association at CERN on 26 May. “PET degrades very slowly and the estimated lifetime of a bottle is 450 years.” In addition to the beach litter accumulated from human use, rivers bring several ki...

  2. Plastic deformation

    NARCIS (Netherlands)

    Sitter, de L.U.

    1937-01-01

    § 1. Plastic deformation of solid matter under high confining pressures has been insufficiently studied. Jeffreys 1) devotes a few paragraphs to deformation of solid matter as a preface to his chapter on the isostasy problem. He distinguishes two properties of solid matter with regard to its

  3. Plastic photochromic eyewear: a status report

    Science.gov (United States)

    Crano, John C.; Elias, Richard C.

    1991-12-01

    An estimated 10 million pairs of photochromic prescription lenses were dispensed in the United States in 1989, essentially all based on a silver halide system suspended in an inorganic glass. A significant trend within the ophthalmic industry has been the growth of light-weight plastic lenses. In the United States market, the percentage of prescription eyewear made of plastic is now greater than 70%. With this increasing market penetration of plastic lenses, the desire for an acceptable plastic photochromic lens has also increased. As with any commercial product, in order to achieve consumer acceptance there exist several technical requirements for a plastic photochromic lens. These include the light transmission and color of the lens in both the unactivated and activated states, the speeds of darkening and fading, and the fatigue resistance or lifetime of the photochromic system. These requirements will be defined along with approaches to achieving them. The properties of the commercially available plastic photochromic lenses will be compared with the defined requirements.

  4. Toward Plastic Smart Windows: Optimization of Indium Tin Oxide Electrodes for the Synthesis of Electrochromic Devices on Polycarbonate Substrates.

    Science.gov (United States)

    Laurenti, Marco; Bianco, Stefano; Castellino, Micaela; Garino, Nadia; Virga, Alessandro; Pirri, Candido F; Mandracci, Pietro

    2016-03-01

    Plastic smart windows are becoming one of the key elements in view of the fabrication of inexpensive, lightweight electrochromic (EC) devices to be integrated in the new generation of high-energy-efficiency buildings and automotive applications. However, fabricating electrochromic devices on polymer substrates requires a reduction of process temperature, so in this work we focus on the development of a completely room-temperature deposition process aimed at the preparation of ITO-coated polycarbonate (PC) structures acting as transparent and conductive plastic supports. Without providing any substrate heating or surface activation pretreatments of the polymer, different deposition conditions are used for growing indium tin oxide (ITO) thin films by the radiofrequency magnetron sputtering technique. According to the characterization results, the set of optimal deposition parameters is selected to deposit ITO electrodes having high optical transmittance in the visible range (∼90%) together with low sheet resistance (∼8 ohm/sq). The as-prepared ITO/PC structures are then successfully tested as conductive supports for the fabrication of plastic smart windows. To this purpose, tungsten trioxide thin films are deposited by the reactive sputtering technique on the ITO/PC structures, and the resulting single electrode EC devices are characterized by chronoamperometric experiments and cyclic voltammetry. The fast switching response between colored and bleached states, together with the stability and reversibility of their electrochromic behavior after several cycling tests, are considered to be representative of the high quality of the EC film but especially of the ITO electrode. Indeed, even if no adhesion promoters, additional surface activation pretreatments, or substrate heating were used to promote the mechanical adhesion among the electrode and the PC surface, the observed EC response confirmed that the developed materials can be successfully employed for the

  5. Type Classes for Lightweight Substructural Types

    Directory of Open Access Journals (Sweden)

    Edward Gan

    2015-02-01

    Full Text Available Linear and substructural types are powerful tools, but adding them to standard functional programming languages often means introducing extra annotations and typing machinery. We propose a lightweight substructural type system design that recasts the structural rules of weakening and contraction as type classes; we demonstrate this design in a prototype language, Clamp. Clamp supports polymorphic substructural types as well as an expressive system of mutable references. At the same time, it adds little additional overhead to a standard Damas-Hindley-Milner type system enriched with type classes. We have established type safety for the core model and implemented a type checker with type inference in Haskell.

  6. Modal analysis for floors in lightweight buildings

    DEFF Research Database (Denmark)

    Sjökvist, Lars-Göran; Brunskog, Jonas

    2007-01-01

    of acoustical prediction methods for those houses. The calculation standard EN 12354 is under evaluation since it cannot include most of the wooden houses that are built. It is important during such a work to have a great understanding of the acoustical behaviour for the wooden houses. The floors in lightweight...... constructions usually consist of plates that are stiffened by beams and by the dividing walls. In this study the wave equation for a plate is expanded by Fourier series and an analytical solution in terms of the eigenmodes of the entire system is presented. The studied system consists of one lightweigt floor...

  7. Lightweight ozonizer for field and airborne use

    Science.gov (United States)

    Stone, E. J.; Caldwell, J. R.; de Waal, C.; Horvath, J. J.; Pearson, R., Jr.; Stedman, D. H.

    1982-12-01

    An efficient, lightweight apparatus for the production of ozone in flowing oxygen or air has been constructed and tested. The exciter is an automotive electronic ignition running from a 28-V dc power source. The discharge tube consists of coaxial conductive-coated flint glass tubing fitting into Teflon end pieces. A single such unit will produce 4% ozone in oxygen flowing at 0.2 l/min, or a maximum of 0.020 l of ozone per minute in a total flow of 1.0 l/min.

  8. Longbow: A Lightweight Remote Job Submission Tool

    Directory of Open Access Journals (Sweden)

    James Gebbie-Rayet

    2016-01-01

    Full Text Available We present Longbow, a lightweight console-based remote job submission tool and library. Longbow allows the user to quickly and simply run jobs on high performance computing facilities without leaving their familiar desktop environment. Not only does Longbow greatly simplify the management of compute- intensive jobs for experienced researchers, it also lowers the technical barriers surrounding high perfor-mance computation for the next generation of scientists and engineers. Longbow has already been used to remotely submit jobs in a number of projects and has the potential to redefine the manner in which high performance computers are used.

  9. A Light-Weight Instrumentation System Design

    International Nuclear Information System (INIS)

    Kidner, Ronald

    1999-01-01

    To meet challenging constraints on telemetry system weight and volume, a custom Light-Weight Instrumentation System was developed to collect vehicle environment and dynamics on a short-duration exo-atmospheric flight test vehicle. The total telemetry system, including electronics, sensors, batteries, and a 1 watt transmitter weighs about 1 kg. Over 80 channels of measurement, housekeeping, and telemetry system diagnostic data are transmitted at 128 kbps. The microcontroller-based design uses the automotive industry standard Controller Area Network to interface with and support in-flight control fimctions. Operational parameters are downloaded via a standard asynchronous serial communications intefiace. The basic design philosophy and functionality is described here

  10. Crushing and Fracture of Lightweight Structures

    DEFF Research Database (Denmark)

    Urban, Jesper

    2003-01-01

    and Latham (1968). Good agreement between the analytical models and the experiments is found. The crushing behaviour of two high speed ferries has been analysed with the numerical and analytical methods and the results are compared with the existing regulations for high speed craft (HSC). Several failure......The overall objective of the present study has been to develop rational analytical and numerical calculation models to quantify the consequences of collision accidents. The work has primarily been focused on high speed craft (HSC) built in lightweight materials such as aluminium and sandwich...

  11. The Micro-Instrumentation Package: A Solution to Lightweight Ballooning

    Science.gov (United States)

    Juneau, Jill

    This paper discusses the design and testing of an over the horizon (OTH) light weight telemetry and termination system that can be used for small ballooning payloads. Currently, the Columbia Scientific Balloon Facility (CSBF) provides telemetry for the science payload by integrating one of two types of support packages. The type of support package integrated depends on whether the flight will stay in range of line of sight (LOS) or will exceed LOS requiring the use of over the horizon (OTH) telemetry. The weights of these systems range from 100 pounds to 350 pounds depending upon the use of redundant systems, equipment for high data rates, and batteries and/or solar panels for power requirements. These weight values are not as significant for larger payloads but can be crippling for smaller payloads. In addition, these support package systems are fairly expensive, placing a high importance on recovery. A lightweight and inexpensive telemetry system could be beneficial for various reasons. First, it would allow scientists to fly lightweight payloads on large balloons reaching even higher altitudes. Second, scientists could fly lightweight payloads on less expensive balloons such as meteorological balloons. Depending on the payload, these flights could be fairly inexpensive and even disposable. Third, a compact telemetry system on any balloon will free up more room for the science portion of the payload. In response, a compact telemetry/termination system called the Micro-Instrumentation Package (MIP) was developed. The MIP provides uplink and downlink communications, an interface to the science, housekeeping information including global positioning system (GPS) position, and relays. Instead of a power-hungry microprocessor, the MIP's central consists of a microcontroller. Microcontrollers are lower power, easily programmed, and can be purchased for less than ten dollars. For uplink and downlink telemetry, the MIP uses an LOS serial transceiver and an Iridium unit

  12. Mix design and properties of fly ash waste lightweight aggregates in structural lightweight concrete

    Directory of Open Access Journals (Sweden)

    Manu S. Nadesan

    2017-12-01

    Full Text Available Concrete is one of the most widely used construction materials and has the ability to consume industrial wastes in high volume. As the demand for concrete is increasing, one of the effective ways to reduce the undesirable environmental impact of the concrete is by the use of waste and by-product materials as cement and aggregate substitutes in concrete. One such waste material is fly ash, which is produced in large quantities from thermal power plants as a by-product. A substantial amount of fly ash is left unused posing environmental and storage problems. The production of sintered lightweight aggregate with fly ash is an effective method to dispose of fly ash in large quantities. Due to lack of a proper mix design procedure, the production and application of lightweight aggregate in structural concrete are not much entertained. The absorption characteristic of lightweight aggregate is a major concern, while developing the mix proportioning of lightweight concretes. The present study is an attempt to establish a new mix design procedure for the development of sintered fly ash lightweight aggregate concretes, which is simple and more reliable than the existing procedures. Also, the proposed methodology has been validated by developing a spectrum of concretes having water cement ratios varying from 0.25 to 0.75. From the study, it is obvious that the development of 70 MPa concrete is possible by using cement alone without any additives. Also, it is ensured that all the concretes have densities less than 2000 kg/m3.

  13. Nigerian Journal of Plastic Surgery

    African Journals Online (AJOL)

    The Nigerian Journal of Plastic Surgery has its objectives in publishing original articles about developments in all areas related to plastic and reconstructive surgery as well as to trauma surgery. It also serves as a means of providing a forum for correspondence, information and discussion. It also accepts review articles that ...

  14. plastic waste recycling

    African Journals Online (AJOL)

    Dr Ahmed

    incinerators is increasing around the world. Discarded plastic products ... Agency (EPA) estimated that the amount of plastics throw away is. 50 % greater in the ... The waste plastics were identified using the Society of the Plastic. Industry (SPI) ...

  15. A comparison of performance of lightweight mirrors

    Science.gov (United States)

    Cho, Myung K.; Richard, Ralph M.; Hileman, Edward A.

    1990-01-01

    Four lightweight solid contoured back mirror shapes (a double arch, a single arch, a modified single arch, and a double concave mirror) and a cellular sandwich lightweight meniscus mirror, have been considered for the primary mirror of the Space Infrared Telescope Facility (SIRTF). A parametric design study using these shapes for the SIRTF 40 inch primary mirror with a focal ratio f/2 is presented. Evaluations of the optical performance and fundamental frequency analyses are performed to compare relative merits of each mirror configuration. Included in these are structural, optical, and frequency analyses for (1) different back contour shapes, (2) different number and location of the support points, and (3) two gravity orientations (ZENITH and HORIZON positions). The finite element program NASTRAN is used to obtain the structural deflections of the optical surface. For wavefront error analysis, FRINGE and PCFRINGE programs are used to evaluate the optical performance. A scaling law relating the optical and structural performance for various mirror contoured back shapes is developed.

  16. Elastic plastic fracture mechanics

    International Nuclear Information System (INIS)

    Simpson, L.A.

    1978-07-01

    The application of linear elastic fracture mechanics (LEFM) to crack stability in brittle structures is now well understood and widely applied. However, in many structural materials, crack propagation is accompanied by considerable crack-tip plasticity which invalidates the use of LEFM. Thus, present day research in fracture mechanics is aimed at developing parameters for predicting crack propagation under elastic-plastic conditions. These include critical crack-opening-displacement methods, the J integral and R-curve techniques. This report provides an introduction to these concepts and gives some examples of their applications. (author)

  17. Lightweight, fire-retardant, crashworthy aircraft seat cushioning

    Science.gov (United States)

    Haslim, Leonard A.; Mcdonough, Paul T.

    1991-01-01

    A two page discussion of non-aerospace seating applications and the design of NASA's safety seat cushioning (SSC) is presented. The SSC was designed for both safety and comfort in order to replace polyurethane cushioning which is flammable and produces lethal fumes upon combustion. The SSC is composed of advanced fabric reinforced composites and is lightweight, fire-retardent, and crashworthy. The seat design consists of central elliptical tubular spring supports made of fire-resistant and fatigue-durable composites surrounded by a fire-blocking sheath. The cushioning is made crashworthy by incorporating energy-absorbing, viscoelastic layers between the nested, elliptical-hoop springs. The design is intended to provide comfortable seating that meets aircraft-loading requirements without using the conventional polyurethane materials. The designs of an aircraft seat and structural components of the SSC are also presented.

  18. AEGIS: A Lightweight Firewall for Wireless Sensor Networks

    Science.gov (United States)

    Hossain, Mohammad Sajjad; Raghunathan, Vijay

    Firewalls are an essential component in today's networked computing systems (desktops, laptops, and servers) and provide effective protection against a variety of over-the-network security attacks. With the development of technologies such as IPv6 and 6LoWPAN that pave the way for Internet-connected embedded systems and sensor networks, these devices will soon be subject to (and need to be defended against) similar security threats. As a first step, this paper presents Aegis, a lightweight, rule-based firewall for networked embedded systems such as wireless sensor networks. Aegis is based on a semantically rich, yet simple, rule definition language. In addition, Aegis is highly efficient during operation, runs in a transparent manner from running applications, and is easy to maintain. Experimental results obtained using real sensor nodes and cycle-accurate simulations demonstrate that Aegis successfully performs gatekeeping of a sensor node's communication traffic in a flexible manner with minimal overheads.

  19. Optical Fibres Contactless Sensor for Dynamic Testing of Lightweight Structures

    Directory of Open Access Journals (Sweden)

    L. Bregant

    2008-01-01

    Full Text Available With dynamic testing, engineers describe activities focused on the identification of some properties of vibrating structures. This step requires for the measurements of excitations and responses signals, applying appropriate sensors directly on the test article. These instruments modify the system's mass and stiffness distributions and eventually the eigen-properties of the structure. These errors become unacceptable especially when testing lightweight structures. This paper shows the results of some tests performed on a small compressor with the purpose of identifying the blades’ natural frequencies and modes. It compares the acquisitions performed with standard accelerometers and two different contact-less systems using as exciters either a micro-hammer or a micro inertial shaker. The paper shows how the contact-less sensors provide good quality data and consistent results in the mode identification phase.

  20. Testosterone and BMD in elite male lightweight rowers

    DEFF Research Database (Denmark)

    Vinther, A; Kanstrup, I-L; Christiansen, E

    2008-01-01

    The purpose of the present study was to investigate if a relationship between BMD and testosterone levels could be identified in elite male lightweight rowers. Thirteen male lightweight national team rowers had their BMD measured in a DEXA scanner. Plasma concentrations of total testosterone (TT)...

  1. Uncertainty and Variation of Vibration in Lightweight Structures

    DEFF Research Database (Denmark)

    Dickow, Kristoffer Ahrens

    2012-01-01

    Multi-family dwellings and offices build from lightweight materials are becoming a cost efficient and environmentally friendly alternative to traditional heavy structures.......Multi-family dwellings and offices build from lightweight materials are becoming a cost efficient and environmentally friendly alternative to traditional heavy structures....

  2. Flexural Performance of Transparent Plastic Bar Reinforced Concrete

    Directory of Open Access Journals (Sweden)

    Byoungil Kim

    2018-02-01

    Full Text Available In this study, experiments were conducted to derive a mix design for improving the flexural performance of light transparent concrete, which is attracting much attention and interest as an interior and exterior material for buildings, so that it could be easily applied in the field as a non-structural element by securing a lightweight, workability, and economic efficiency through the improvement of the concrete mix design and the use of economical materials for promoting its practical use. It was found that the mixing of polyvinyl alcohol (PVA fiber was effective in improving the consistency by preventing the aggregate from floating due to the mixing of lightweight aggregate with a low specific gravity. The flexural performance test results showed that the load transfer factor (LTF from the concrete matrix to the fiber was highest in the test specimens without plastic bars, followed by those with 5 and 10 mm plastic bars, respectively.

  3. Plastic food packaging and health

    Directory of Open Access Journals (Sweden)

    Raika Durusoy

    2011-02-01

    Full Text Available Plastics have a wide usage in our daily lives. One of their uses is for food packaging and food containers. The aim of this review is to introduce different types of chemicals that can leach from food packaging plastics into foods and cause human exposure and to mention their effects on health. The types of plastics were reviewed under the 13 headings in Turkish Codex Alimentarius and plastics recycling symbols were provided to enable the recognition of the type of plastic when applicable. Chemicals used during the production and that can cause health risks are investigated under the heading of the relevant type of plastic. The most important chemicals from plastic food packaging that can cause toxicity are styrene, 1,3-butadiene, melamine, formaldehyde, acrylamide, di-2-ethylhexyl phthalate, di-2-ethylhexyl adipate, vinyl chloride and bisphenol A. These chemicals have endocrine disrupting, carcinogenic and/or development disrupting effects. These chemicals may leach into foods depending on the chemical properties of the plastic or food, temperature during packaging, processing and storage, exposure to UV and duration of storage. Contact with fatty/oily or acidic foods, heating of the food inside the container, or drinking hot drinks from plastic cups, use of old and scratched plastics and some detergents increase the risk of leaching. The use of plastic containers and packaging for food and beveradges should be avoided whenever possible and when necessary, less harmful types of plastic should be preferred. [TAF Prev Med Bull 2011; 10(1.000: 87-96

  4. Fe–Al–Mn–C lightweight structural alloys: a review on the microstructures and mechanical properties

    Directory of Open Access Journals (Sweden)

    Hansoo Kim, Dong-Woo Suh and Nack J Kim

    2013-01-01

    Full Text Available Adding a large amount of light elements such as aluminum to steels is not a new concept recalling that several Fe–Al–Mn–C alloys were patented in 1950s for replacement of nickel or chromium in corrosion resistance steels. However, the so-called lightweight steels or low-density steels were revisited recently, which is driven by demands from the industry where steel has served as a major structural material. Strengthening without loss of ductility has been a triumph in steel research, but lowering the density of steel by mixing with light elements will be another prospect that may support the competitiveness against emerging alternatives such as magnesium alloys. In this paper, we review recent studies on lightweight steels, emphasizing the concept of alloy design for microstructures and mechanical properties. The influence of alloying elements on the phase constituents, mechanical properties and the change of density is critically reviewed. Deformation mechanisms of various lightweight steels are discussed as well. This paper provides a reason why the success of lightweight steels is strongly dependent on scientific achievements even though alloy development is closely related to industrial applications. Finally, we summarize some of the main directions for future investigations necessary for vitalizing this field of interest.

  5. Alkali-silica reactivity of expanded glass granules in structure of lightweight concrete

    International Nuclear Information System (INIS)

    Bumanis, G; Bajare, D; Korjakins, A; Locs, J

    2013-01-01

    Main component in the lightweight concrete, which provides its properties, is aggregate. A lot of investigations on alkali silica reaction (ASR) between cement and lightweight aggregates have been done with their results published in the academic literature. Whereas expanded glass granules, which is relatively new product in the market of building materials, has not been a frequent research object. Therefore lightweight granules made from waste glass and eight types of cement with different chemical and mineralogical composition were examined in this research. Expanded glass granules used in this research is commercially available material produced by Penostek. Lightweight concrete mixtures were prepared by using commercial chemical additives to improve workability of concrete. The aim of the study is to identify effect of cement composition to the ASR reaction which occurs between expanded glass granules and binder. Expanded glass granules mechanical and physical properties were determined. In addition, properties of fresh and hardened concrete were determined. The ASR test was processed according to RILEM AAR-2 testing recommendation. Tests with scanning electron microscope and microstructural investigations were performed for expanded glass granules and hardened concrete specimens before and after exposing them in alkali solution

  6. Fe–Al–Mn–C lightweight structural alloys: a review on the microstructures and mechanical properties

    Science.gov (United States)

    Kim, Hansoo; Suh, Dong-Woo; Kim, Nack J

    2013-01-01

    Adding a large amount of light elements such as aluminum to steels is not a new concept recalling that several Fe–Al–Mn–C alloys were patented in 1950s for replacement of nickel or chromium in corrosion resistance steels. However, the so-called lightweight steels or low-density steels were revisited recently, which is driven by demands from the industry where steel has served as a major structural material. Strengthening without loss of ductility has been a triumph in steel research, but lowering the density of steel by mixing with light elements will be another prospect that may support the competitiveness against emerging alternatives such as magnesium alloys. In this paper, we review recent studies on lightweight steels, emphasizing the concept of alloy design for microstructures and mechanical properties. The influence of alloying elements on the phase constituents, mechanical properties and the change of density is critically reviewed. Deformation mechanisms of various lightweight steels are discussed as well. This paper provides a reason why the success of lightweight steels is strongly dependent on scientific achievements even though alloy development is closely related to industrial applications. Finally, we summarize some of the main directions for future investigations necessary for vitalizing this field of interest. PMID:27877553

  7. Fe-Al-Mn-C lightweight structural alloys: a review on the microstructures and mechanical properties.

    Science.gov (United States)

    Kim, Hansoo; Suh, Dong-Woo; Kim, Nack J

    2013-02-01

    Adding a large amount of light elements such as aluminum to steels is not a new concept recalling that several Fe-Al-Mn-C alloys were patented in 1950s for replacement of nickel or chromium in corrosion resistance steels. However, the so-called lightweight steels or low-density steels were revisited recently, which is driven by demands from the industry where steel has served as a major structural material. Strengthening without loss of ductility has been a triumph in steel research, but lowering the density of steel by mixing with light elements will be another prospect that may support the competitiveness against emerging alternatives such as magnesium alloys. In this paper, we review recent studies on lightweight steels, emphasizing the concept of alloy design for microstructures and mechanical properties. The influence of alloying elements on the phase constituents, mechanical properties and the change of density is critically reviewed. Deformation mechanisms of various lightweight steels are discussed as well. This paper provides a reason why the success of lightweight steels is strongly dependent on scientific achievements even though alloy development is closely related to industrial applications. Finally, we summarize some of the main directions for future investigations necessary for vitalizing this field of interest.

  8. Lightweight and Statistical Techniques for Petascale PetaScale Debugging

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Barton

    2014-06-30

    This project investigated novel techniques for debugging scientific applications on petascale architectures. In particular, we developed lightweight tools that narrow the problem space when bugs are encountered. We also developed techniques that either limit the number of tasks and the code regions to which a developer must apply a traditional debugger or that apply statistical techniques to provide direct suggestions of the location and type of error. We extend previous work on the Stack Trace Analysis Tool (STAT), that has already demonstrated scalability to over one hundred thousand MPI tasks. We also extended statistical techniques developed to isolate programming errors in widely used sequential or threaded applications in the Cooperative Bug Isolation (CBI) project to large scale parallel applications. Overall, our research substantially improved productivity on petascale platforms through a tool set for debugging that complements existing commercial tools. Previously, Office Of Science application developers relied either on primitive manual debugging techniques based on printf or they use tools, such as TotalView, that do not scale beyond a few thousand processors. However, bugs often arise at scale and substantial effort and computation cycles are wasted in either reproducing the problem in a smaller run that can be analyzed with the traditional tools or in repeated runs at scale that use the primitive techniques. New techniques that work at scale and automate the process of identifying the root cause of errors were needed. These techniques significantly reduced the time spent debugging petascale applications, thus leading to a greater overall amount of time for application scientists to pursue the scientific objectives for which the systems are purchased. We developed a new paradigm for debugging at scale: techniques that reduced the debugging scenario to a scale suitable for traditional debuggers, e.g., by narrowing the search for the root-cause analysis

  9. Process combinations for the manufacturing of metal-plastic hybrid parts

    International Nuclear Information System (INIS)

    Drossel, W-G; Lies, C; Albert, A; Haase, R; Müller, R; Scholz, P

    2016-01-01

    The usage of innovative lightweight materials and processing technologies gains importance in manifold industrial scopes. Especially for moving parts and mobility products the weight is decisively. The aerospace and automotive industries use light and high-strength materials to reduce weight and energy consumption and thereby improve the performance of their products. Composites with reinforced plastics are of particular importance. They offer a low density in combination with high specific stiffness and strength. A pure material substitution through reinforced plastics is still not economical. The approach of using hybrid metal-plastic structures with the principle of “using the right material at the right place” is a promising solution for the economical realization of lightweight structures with a high achievement potential. The article shows four innovative manufacturing possibilities for the realization of metal-plastic-hybrid parts. (paper)

  10. Lightweight High Efficiency Electric Motors for Space Applications

    Science.gov (United States)

    Robertson, Glen A.; Tyler, Tony R.; Piper, P. J.

    2011-01-01

    Lightweight high efficiency electric motors are needed across a wide range of space applications from - thrust vector actuator control for launch and flight applications to - general vehicle, base camp habitat and experiment control for various mechanisms to - robotics for various stationary and mobile space exploration missions. QM Power?s Parallel Path Magnetic Technology Motors have slowly proven themselves to be a leading motor technology in this area; winning a NASA Phase II for "Lightweight High Efficiency Electric Motors and Actuators for Low Temperature Mobility and Robotics Applications" a US Army Phase II SBIR for "Improved Robot Actuator Motors for Medical Applications", an NSF Phase II SBIR for "Novel Low-Cost Electric Motors for Variable Speed Applications" and a DOE SBIR Phase I for "High Efficiency Commercial Refrigeration Motors" Parallel Path Magnetic Technology obtains the benefits of using permanent magnets while minimizing the historical trade-offs/limitations found in conventional permanent magnet designs. The resulting devices are smaller, lower weight, lower cost and have higher efficiency than competitive permanent magnet and non-permanent magnet designs. QM Power?s motors have been extensively tested and successfully validated by multiple commercial and aerospace customers and partners as Boeing Research and Technology. Prototypes have been made between 0.1 and 10 HP. They are also in the process of scaling motors to over 100kW with their development partners. In this paper, Parallel Path Magnetic Technology Motors will be discussed; specifically addressing their higher efficiency, higher power density, lighter weight, smaller physical size, higher low end torque, wider power zone, cooler temperatures, and greater reliability with lower cost and significant environment benefit for the same peak output power compared to typically motors. A further discussion on the inherent redundancy of these motors for space applications will be provided.

  11. A lightweight communication library for distributed computing

    International Nuclear Information System (INIS)

    Groen, Derek; Rieder, Steven; Zwart, Simon Portegies; Grosso, Paola; Laat, Cees de

    2010-01-01

    We present MPWide, a platform-independent communication library for performing message passing between computers. Our library allows coupling of several local message passing interface (MPI) applications through a long-distance network and is specifically optimized for such communications. The implementation is deliberately kept lightweight and platform independent, and the library can be installed and used without administrative privileges. The only requirements are a C++ compiler and at least one open port to a wide-area network on each site. In this paper we present the library, describe the user interface, present performance tests and apply MPWide in a large-scale cosmological N-body simulation on a network of two computers, one in Amsterdam and the other in Tokyo.

  12. Lightweight, durable lead-acid batteries

    Science.gov (United States)

    Lara-Curzio, Edgar; An, Ke; Kiggans, Jr., James O; Dudney, Nancy J; Contescu, Cristian I; Baker, Frederick S; Armstrong, Beth L

    2013-05-21

    A lightweight, durable lead-acid battery is disclosed. Alternative electrode materials and configurations are used to reduce weight, to increase material utilization and to extend service life. The electrode can include a current collector having a buffer layer in contact with the current collector and an electrochemically active material in contact with the buffer layer. In one form, the buffer layer includes a carbide, and the current collector includes carbon fibers having the buffer layer. The buffer layer can include a carbide and/or a noble metal selected from of gold, silver, tantalum, platinum, palladium and rhodium. When the electrode is to be used in a lead-acid battery, the electrochemically active material is selected from metallic lead (for a negative electrode) or lead peroxide (for a positive electrode).

  13. Lightweight Active Object Retrieval with Weak Classifiers.

    Science.gov (United States)

    Czúni, László; Rashad, Metwally

    2018-03-07

    In the last few years, there has been a steadily growing interest in autonomous vehicles and robotic systems. While many of these agents are expected to have limited resources, these systems should be able to dynamically interact with other objects in their environment. We present an approach where lightweight sensory and processing techniques, requiring very limited memory and processing power, can be successfully applied to the task of object retrieval using sensors of different modalities. We use the Hough framework to fuse optical and orientation information of the different views of the objects. In the presented spatio-temporal perception technique, we apply active vision, where, based on the analysis of initial measurements, the direction of the next view is determined to increase the hit-rate of retrieval. The performance of the proposed methods is shown on three datasets loaded with heavy noise.

  14. Lightweight Active Object Retrieval with Weak Classifiers

    Directory of Open Access Journals (Sweden)

    László Czúni

    2018-03-01

    Full Text Available In the last few years, there has been a steadily growing interest in autonomous vehicles and robotic systems. While many of these agents are expected to have limited resources, these systems should be able to dynamically interact with other objects in their environment. We present an approach where lightweight sensory and processing techniques, requiring very limited memory and processing power, can be successfully applied to the task of object retrieval using sensors of different modalities. We use the Hough framework to fuse optical and orientation information of the different views of the objects. In the presented spatio-temporal perception technique, we apply active vision, where, based on the analysis of initial measurements, the direction of the next view is determined to increase the hit-rate of retrieval. The performance of the proposed methods is shown on three datasets loaded with heavy noise.

  15. Development of a lightweight fuel cell vehicle

    Science.gov (United States)

    Hwang, J. J.; Wang, D. Y.; Shih, N. C.

    This paper described the development of a fuel cell system and its integration into the lightweight vehicle known as the Mingdao hydrogen vehicle (MHV). The fuel cell system consists of a 5-kW proton exchange membrane fuel cell (PEMFC), a microcontroller and other supported components like a compressed hydrogen cylinder, blower, solenoid valve, pressure regulator, water pump, heat exchanger and sensors. The fuel cell not only propels the vehicle but also powers the supporting components. The MHV performs satisfactorily over a hundred-kilometer drive thus validating the concept of a fuel cell powered zero-emission vehicle. Measurements further show that the fuel cell system has an efficiency of over 30% at the power consumption for vehicle cruise, which is higher than that of a typical internal combustion engine. Tests to improve performance such as speed enhancement, acceleration and fuel efficiency will be conducted in the future work. Such tests will consist of hybridizing with a battery pack.

  16. Lightweight MIPv6 with IPSec Support

    Directory of Open Access Journals (Sweden)

    Antonio J. Jara

    2014-01-01

    Full Text Available Mobility management is a desired feature for the emerging Internet of Things (IoT. Mobility aware solutions increase the connectivity and enhance adaptability to changes of the location and infrastructure. IoT is enabling a new generation of dynamic ecosystems in environments such as smart cities and hospitals. Dynamic ecosystems require ubiquitous access to Internet, seamless handover, flexible roaming policies, and an interoperable mobility protocol with existing Internet infrastructure. These features are challenges for IoT devices, which are usually constrained devices with low memory, processing, communication and energy capabilities. This work presents an analysis of the requirements and desirable features for the mobility support in the IoT, and proposes an efficient solution for constrained environments based on Mobile IPv6 and IPSec. Compatibility with IPv6-existing protocols has been considered a major requirement in order to offer scalable and inter-domain solutions that were not limited to specific application domains in order to enable a new generation of application and services over Internet-enabled dynamic ecosystems, and security support based on IPSec has been also considered, since dynamic ecosystems present several challenges in terms of security and privacy. This work has, on the one hand, analysed suitability of Mobile IPv6 and IPSec for constrained devices, and on the other hand, analysed, designed, developed and evaluated a lightweight version of Mobile IPv6 and IPSec. The proposed solution of lightweight Mobile IPv6 with IPSec is aware of the requirements of the IoT and presents the best solution for dynamic ecosystems in terms of efficiency and security adapted to IoT-devices capabilities. This presents concerns in terms of higher overhead and memory requirements. But, it is proofed and concluded that even when higher memory is required and major overhead is presented, the integration of Mobile IPv6 and IPSec for

  17. Upgrading the Center for Lightweighting Automotive Materials and Processing - a GATE Center of Excellence at the University of Michigan-Dearborn

    Energy Technology Data Exchange (ETDEWEB)

    Mallick, P. K.

    2012-08-30

    accessible to outside users (5) provide support to graduate students for conducting research on lightweight automotive materials and structures (6) provide industry/university interaction through a graduate certificate program on automotive materials and technology idea exchange through focused seminars and symposia on automotive materials.

  18. Field Performance of Recycled Plastic Foundation for Pipeline

    Science.gov (United States)

    Kim, Seongkyum; Lee, Kwanho

    2015-01-01

    The incidence of failure of embedded pipelines has increased in Korea due to the increasing applied load and the improper compaction of bedding and backfill materials. To overcome these problems, a prefabricated lightweight plastic foundation using recycled plastic was developed for sewer pipelines. A small scale laboratory chamber test and two field tests were conducted to verify its construction workability and performance. From the small scale laboratory chamber test, the applied loads at 2.5% and 5.0% of deformation were 3.45 kgf/cm2 and 5.85 kgf/cm2 for Case S1, and 4.42 kgf/cm2 and 6.43 kgf/cm2 for Case S2, respectively. From the first field test, the vertical deformation of the recycled plastic foundation (Case A2) was very small. According to the analysis based on the PE pipe deformation at the connection (CN) and at the center (CT), the pipe deformation at each part for Case A1 was larger than that for Case A2, which adopted the recycled lightweight plastic foundation. From the second field test, the measured maximum settlements of Case B1 and Case B2 were 1.05 cm and 0.54 cm, respectively. The use of a plastic foundation can reduce the settlement of an embedded pipeline and be an alternative construction method.

  19. Field Performance of Recycled Plastic Foundation for Pipeline

    Directory of Open Access Journals (Sweden)

    Seongkyum Kim

    2015-05-01

    Full Text Available The incidence of failure of embedded pipelines has increased in Korea due to the increasing applied load and the improper compaction of bedding and backfill materials. To overcome these problems, a prefabricated lightweight plastic foundation using recycled plastic was developed for sewer pipelines. A small scale laboratory chamber test and two field tests were conducted to verify its construction workability and performance. From the small scale laboratory chamber test, the applied loads at 2.5% and 5.0% of deformation were 3.45 kgf/cm2 and 5.85 kgf/cm2 for Case S1, and 4.42 kgf/cm2 and 6.43 kgf/cm2 for Case S2, respectively. From the first field test, the vertical deformation of the recycled plastic foundation (Case A2 was very small. According to the analysis based on the PE pipe deformation at the connection (CN and at the center (CT, the pipe deformation at each part for Case A1 was larger than that for Case A2, which adopted the recycled lightweight plastic foundation. From the second field test, the measured maximum settlements of Case B1 and Case B2 were 1.05 cm and 0.54 cm, respectively. The use of a plastic foundation can reduce the settlement of an embedded pipeline and be an alternative construction method.

  20. Vehicle Lightweighting: Mass Reduction Spectrum Analysis and Process Cost Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Mascarin, Anthony [IBIS Associates, Inc., Waltham, MA (United States); Hannibal, Ted [IBIS Associates, Inc., Waltham, MA (United States); Raghunathan, Anand [Energetics Inc., Columbia, MD (United States); Ivanic, Ziga [Energetics Inc., Columbia, MD (United States); Clark, Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-03-01

    The U.S. Department of Energy’s Vehicle Technologies Office, Materials area commissioned a study to model and assess manufacturing economics of alternative design and production strategies for a series of lightweight vehicle concepts. In the first two phases of this effort examined combinations of strategies aimed at achieving strategic targets of 40% and a 45% mass reduction relative to a standard North American midsize passenger sedan at an effective cost of $3.42 per pound (lb) saved. These results have been reported in the Idaho National Laboratory report INL/EXT-14-33863 entitled Vehicle Lightweighting: 40% and 45% Weight Savings Analysis: Technical Cost Modeling for Vehicle Lightweighting published in March 2015. The data for these strategies were drawn from many sources, including Lotus Engineering Limited and FEV, Inc. lightweighting studies, U.S. Department of Energy-funded Vehma International of America, Inc./Ford Motor Company Multi-Material Lightweight Prototype Vehicle Demonstration Project, the Aluminum Association Transportation Group, many United States Council for Automotive Research’s/United States Automotive Materials Partnership LLC lightweight materials programs, and IBIS Associates, Inc.’s decades of experience in automotive lightweighting and materials substitution analyses.

  1. Vehicle Lightweighting: Mass Reduction Spectrum Analysis and Process Cost Modeling

    International Nuclear Information System (INIS)

    Mascarin, Anthony; Hannibal, Ted; Raghunathan, Anand; Ivanic, Ziga; Clark, Michael

    2016-01-01

    The U.S. Department of Energy's Vehicle Technologies Office, Materials area commissioned a study to model and assess manufacturing economics of alternative design and production strategies for a series of lightweight vehicle concepts. In the first two phases of this effort examined combinations of strategies aimed at achieving strategic targets of 40% and a 45% mass reduction relative to a standard North American midsize passenger sedan at an effective cost of $3.42 per pound (lb) saved. These results have been reported in the Idaho National Laboratory report INL/EXT-14-33863 entitled Vehicle Lightweighting: 40% and 45% Weight Savings Analysis: Technical Cost Modeling for Vehicle Lightweighting published in March 2015. The data for these strategies were drawn from many sources, including Lotus Engineering Limited and FEV, Inc. lightweighting studies, U.S. Department of Energy-funded Vehma International of America, Inc./Ford Motor Company Multi-Material Lightweight Prototype Vehicle Demonstration Project, the Aluminum Association Transportation Group, many United States Council for Automotive Research's/United States Automotive Materials Partnership LLC lightweight materials programs, and IBIS Associates, Inc.'s decades of experience in automotive lightweighting and materials substitution analyses.

  2. Carbody structural lightweighting based on implicit parameterized model

    Science.gov (United States)

    Chen, Xin; Ma, Fangwu; Wang, Dengfeng; Xie, Chen

    2014-05-01

    Most of recent research on carbody lightweighting has focused on substitute material and new processing technologies rather than structures. However, new materials and processing techniques inevitably lead to higher costs. Also, material substitution and processing lightweighting have to be realized through body structural profiles and locations. In the huge conventional workload of lightweight optimization, model modifications involve heavy manual work, and it always leads to a large number of iteration calculations. As a new technique in carbody lightweighting, the implicit parameterization is used to optimize the carbody structure to improve the materials utilization rate in this paper. The implicit parameterized structural modeling enables the use of automatic modification and rapid multidisciplinary design optimization (MDO) in carbody structure, which is impossible in the traditional structure finite element method (FEM) without parameterization. The structural SFE parameterized model is built in accordance with the car structural FE model in concept development stage, and it is validated by some structural performance data. The validated SFE structural parameterized model can be used to generate rapidly and automatically FE model and evaluate different design variables group in the integrated MDO loop. The lightweighting result of body-in-white (BIW) after the optimization rounds reveals that the implicit parameterized model makes automatic MDO feasible and can significantly improve the computational efficiency of carbody structural lightweighting. This paper proposes the integrated method of implicit parameterized model and MDO, which has the obvious practical advantage and industrial significance in the carbody structural lightweighting design.

  3. Lightweight Phase-Change Material For Solar Power

    Science.gov (United States)

    Stark, Philip

    1993-01-01

    Lightweight panels containing phase-change materials developed for use as heat-storage elements of compact, lightweight, advanced solar dynamic power system. During high insolation, heat stored in panels via latent heat of fusion of phase-change material; during low insolation, heat withdrawn from panels. Storage elements consist mainly of porous carbon-fiber structures imbued with germanium. Developed for use aboard space station in orbit around Earth, also adapted to lightweight, compact, portable solar-power systems for use on Earth.

  4. Enabling lightweight designs by a new laser based approach for joining aluminum to steel

    Science.gov (United States)

    Brockmann, Rüdiger; Kaufmann, Sebastian; Kirchhoff, Marc; Candel-Ruiz, Antonio; Müllerschön, Oliver; Havrilla, David

    2015-03-01

    As sustainability is an essential requirement, lightweight design becomes more and more important, especially for mobility. Reduced weight ensures more efficient vehicles and enables better environmental impact. Besides the design, new materials and material combinations are one major trend to achieve the required weight savings. The use of Carbon Fiber Reinforced Plastics (abbr. CFRP) is widely discussed, but so far high volume applications are rarely to be found. This is mainly due to the fact that parts made of CFRP are much more expensive than conventional parts. Furthermore, the proper technologies for high volume production are not yet ready. Another material with a large potential for lightweight design is aluminum. In comparison to CFRP, aluminum alloys are generally more affordable. As aluminum is a metallic material, production technologies for high volume standard cutting or joining applications are already developed. In addition, bending and deep-drawing can be applied. In automotive engineering, hybrid structures such as combining high-strength steels with lightweight aluminum alloys retain significant weight reduction but also have an advantage over monolithic aluminum - enhanced behavior in case of crash. Therefore, since the use of steel for applications requiring high mechanical properties is unavoidable, methods for joining aluminum with steel parts have to be further developed. Former studies showed that the use of a laser beam can be a possibility to join aluminum to steel parts. In this sense, the laser welding process represents a major challenge, since both materials have different thermal expansion coefficients and properties related to the behavior in corrosive media. Additionally, brittle intermetallic phases are formed during welding. A promising approach to welding aluminum to steel is based on the use of Laser Metal Deposition (abbr. LMD) with deposit materials in the form of powders. Within the present work, the advantages of this

  5. Design and manufacture of a lightweight piezo-composite curved actuator

    Science.gov (United States)

    Yoon, K. Joon; Shin, Seokjun; Park, Hoon C.; Goo, Nam Seo

    2002-02-01

    In this paper we are concerned with the design, manufacture and performance test of a lightweight piezo-composite curved actuator (called LIPCA) using a top carbon fiber composite layer with near-zero coefficient of thermal expansion (CTE), a middle PZT ceramic wafer, and a bottom glass/epoxy layer with a high CTE. The main point of the design for LIPCA is to replace the heavy metal layers of THUNDERTM by lightweight fiber reinforced plastic layers without losing the capabilities for generating high force and large displacement. It is possible to save up to about 40% of the weight if we replace the metallic backing material by the light fiber composite layer. We can also have design flexibility by selecting the fiber direction and the size of prepreg layers. In addition to the lightweight advantage and design flexibility, the proposed device can be manufactured without adhesive layers when we use an epoxy resin prepreg system. Glass/epoxy prepregs, a ceramic wafer with electrode surfaces, and a carbon prepreg were simply stacked and cured at an elevated temperature (177 °C) after following an autoclave bagging process. We found that the manufactured composite laminate device had a sufficient curvature after being detached from a flat mould. An analysis method using the classical lamination theory is presented to predict the curvature of LIPCA after curing at an elevated temperature. The predicted curvatures are in quite good agreement with the experimental values. In order to investigate the merits of LIPCA, performance tests of both LIPCA and THUNDERTM have been conducted under the same boundary conditions. From the experimental actuation tests, it was observed that the developed actuator could generate larger actuation displacement than THUNDERTM.

  6. Plastic scintillator

    International Nuclear Information System (INIS)

    Andreeshchev, E.A.; Kilin, S.F.; Kavyrzina, K.A.

    1978-01-01

    A plastic scintillator for ionizing radiation detectors with high time resolution is suggested. To decrease the scintillation pulse width and to maintain a high light yield, the 4 1 , 4 5 -dibromo-2 1 , 2 5 , 5 1 , 5 5 -tetramethyl-n-quinquiphenyl (Br 2 Me 4 Ph) in combination with n-terphenyl (Ph 3 ) or 2, 5-diphenyloxadiazol-1, 3, 4 (PPD) is used as a luminescent addition. Taking into consideration the results of a special study, it is shown, that the following ratio of ingradients is the optimum one: 3-4 mass% Ph 3 or 4-7 mas% PPD + 2-5 mass% Br 2 Me 4 Ph + + polymeric base. The suggested scintillator on the basis of polystyrene has the light yield of 0.23-0.26 arbitrary units and the scintillation pulse duration at half-height is 0.74-0.84 ns

  7. Arabidopsis thaliana population analysis reveals high plasticity of the genomic region spanning MSH2, AT3G18530 and AT3G18535 genes and provides evidence for NAHR-driven recurrent CNV events occurring in this location.

    Science.gov (United States)

    Zmienko, Agnieszka; Samelak-Czajka, Anna; Kozlowski, Piotr; Szymanska, Maja; Figlerowicz, Marek

    2016-11-08

    Intraspecies copy number variations (CNVs), defined as unbalanced structural variations of specific genomic loci, ≥1 kb in size, are present in the genomes of animals and plants. A growing number of examples indicate that CNVs may have functional significance and contribute to phenotypic diversity. In the model plant Arabidopsis thaliana at least several hundred protein-coding genes might display CNV; however, locus-specific genotyping studies in this plant have not been conducted. We analyzed the natural CNVs in the region overlapping MSH2 gene that encodes the DNA mismatch repair protein, and AT3G18530 and AT3G18535 genes that encode poorly characterized proteins. By applying multiplex ligation-dependent probe amplification and droplet digital PCR we genotyped those genes in 189 A. thaliana accessions. We found that AT3G18530 and AT3G18535 were duplicated (2-14 times) in 20 and deleted in 101 accessions. MSH2 was duplicated in 12 accessions (up to 12-14 copies) but never deleted. In all but one case, the MSH2 duplications were associated with those of AT3G18530 and AT3G18535. Considering the structure of the CNVs, we distinguished 5 genotypes for this region, determined their frequency and geographical distribution. We defined the CNV breakpoints in 35 accessions with AT3G18530 and AT3G18535 deletions and tandem duplications and showed that they were reciprocal events, resulting from non-allelic homologous recombination between 99 %-identical sequences flanking these genes. The widespread geographical distribution of the deletions supported by the SNP and linkage disequilibrium analyses of the genomic sequence confirmed the recurrent nature of this CNV. We characterized in detail for the first time the complex multiallelic CNV in Arabidopsis genome. The region encoding MSH2, AT3G18530 and AT3G18535 genes shows enormous variation of copy numbers among natural ecotypes, being a remarkable example of high Arabidopsis genome plasticity. We provided the molecular

  8. Nano-Ceramic Coated Plastics

    Science.gov (United States)

    Cho, Junghyun

    2013-01-01

    Plastic products, due to their durability, safety, and low manufacturing cost, are now rapidly replacing cookware items traditionally made of glass and ceramics. Despite this trend, some still prefer relatively expensive and more fragile ceramic/glassware because plastics can deteriorate over time after exposure to foods, which can generate odors, bad appearance, and/or color change. Nano-ceramic coatings can eliminate these drawbacks while still retaining the advantages of the plastic, since the coating only alters the surface of the plastic. The surface coating adds functionality to the plastics such as self-cleaning and disinfectant capabilities that result from a photocatalytic effect of certain ceramic systems. These ceramic coatings can also provide non-stick surfaces and higher temperature capabilities for the base plastics without resorting to ceramic or glass materials. Titanium dioxide (TiO2) and zinc oxide (ZnO) are the candidates for a nano-ceramic coating to deposit on the plastics or plastic films used in cookware and kitchenware. Both are wide-bandgap semiconductors (3.0 to 3.2 eV for TiO2 and 3.2 to 3.3 eV for ZnO), so they exhibit a photocatalytic property under ultraviolet (UV) light. This will lead to decomposition of organic compounds. Decomposed products can be easily washed off by water, so the use of detergents will be minimal. High-crystalline film with large surface area for the reaction is essential to guarantee good photocatalytic performance of these oxides. Low-temperature processing (nano-ceramic coatings (TiO2, ZnO) on plastic materials (silicone, Teflon, PET, etc.) that can possess both photocatalytic oxide properties and flexible plastic properties. Processing cost is low and it does not require any expensive equipment investment. Processing can be scalable to current manufacturing infrastructure.

  9. Toxicological Threats of Plastic

    Science.gov (United States)

    Plastics pose both physical (e.g., entanglement, gastrointestinal blockage, reef destruction) and chemical threats (e.g., bioaccumulation of the chemical ingredients of plastic or toxic chemicals sorbed to plastics) to wildlife and the marine ecosystem.

  10. Lightweight landscape enhancing design through minimal mass structures

    CERN Document Server

    Spinelli, Luigi; Monticelli, Carol; Pedrali, Paolo

    2016-01-01

    This book explains how lightweight materials and structures can be deployed in buildings to meet high environmental and aesthetic standards and emphasizes how the concept of lightness in building technology and design dovetails with the desire to enhance landscape. The first part of the book, on lightweight construction, aims to foster the use of membranes within the specific climatic context and in particular considers how lightweight materials and innovative technologies can enrich the quality of temporary spaces. The second part focuses exclusively on landscape, presenting novel approaches in the search for visual lightness and the quest to improve urban spaces. Particular attention is paid to the Italian experience, where the traditional appreciation of brick and stone has limited the scope for use of lightweight structures and membrane materials, often relegating them to a secondary or inappropriate role. The reader will come to appreciate how this attitude demeans a very advanced productive sector and n...

  11. Lightweight cordierite–mullite refractories with low coefficients of ...

    Indian Academy of Sciences (India)

    of thermal conductivity and high mechanical properties ... compositions and microstructures of lightweight refractories were measured by X-ray .... of matrices were determined by calibration with EDAX ZAF .... Guzman I Ya 2003 Glass Ceram.

  12. Ultra-Lightweight Large Aperture Support Structures, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Ultra-lightweight membranes may prove to be very attractive for large aperture systems, but their value will be fully realized only if they are mated with equally...

  13. Ontology learning from interpretations in lightweight description logics

    CSIR Research Space (South Africa)

    Klarman, S

    2015-08-01

    Full Text Available International Conference on Inductive Logic programming (ILP), Kyoto, Japan, 20-22 August 2015 Ontology Learning from Interpretations in Lightweight Description Logics Szymon Klarman1 and Katarina Britz2 1 Department of Computer Science, Brunel...

  14. A Stepped Frequency CW SAR for Lightweight UAV Operation

    National Research Council Canada - National Science Library

    Morrison, Keith

    2005-01-01

    A stepped-frequency continuous wave (SF-CW) synthetic aperture radar (SAR), with frequency-agile waveforms and real-time intelligent signal processing algorithms, is proposed for operation from a lightweight UAV platform...

  15. Durability of lightweight concrete : Phase I : concrete temperature study.

    Science.gov (United States)

    1968-08-01

    This report describes a study conducted to determine the temperature gradient throughout the depth of a six inch concrete bridge deck. The bridge deck selected for study was constructed using lightweight concrete for the center spans and sand and gra...

  16. Lightweight geopolymer composites as structural elements with improved insulation capacity

    Directory of Open Access Journals (Sweden)

    Kakali Glikeria

    2018-01-01

    Full Text Available This study concerns the development of lightweight fly ash based geopolymers which can be applied as alternatives to the traditional lightweight concrete. Different kinds of expanded polystyrene were used as lightweight agents. The results showed that lightweight geopolymers were successfully prepared, exhibiting compressive strength and density in the range 7.70 – 29.57 MPa and 0.97 – 1.57 g/cm3, respectively. The product containing 3% w/w of commercial expanded polystyrene possesses low thermal conductivity (0.16 W/mK combined with sufficient mechanical strengths (11 MPa, excellent stability and fire resistance while its water absorption is comparable to that of conventional construction materials (cement mortars, concrete.

  17. Feasibility Study on Manufacturing Lightweight Aggregates from Water Purification Sludge

    Science.gov (United States)

    Peng, Ching-Fang; Chen, How-Ji

    2018-02-01

    This study mainly discussed the feasibility of manufacturing lightweight aggregates from water purification sludge in Taiwan. They were analysed for the physical and chemical composition before the sintering test for lightweight aggregates in a laboratory. Then the physical and mechanical properties of the synthesized aggregates were assessed. The result showed that the chemical composition of sludge in the water purification plants was within the appropriate range for manufacturing lightweight aggregate as proposed in the literature. The sintering test demonstrated that the particle density of aggregates from the ten types of water purification sludge were mostly less than 1.8 g/cm3. In addition, the dry unit weight, the organic impurity, the ignition loss, and other characteristics of synthesized aggregates met the requirement of CNS standards, while its water absorption and crushing strength also fulfilled the general commercial specifications. Therefore, reclamation of water purification sludge for production of lightweight aggregate is indeed feasible.

  18. Plastic footwear for leprosy.

    Science.gov (United States)

    Antia, N H

    1990-03-01

    The anaesthetic foot in leprosy poses the most major problem in the rehabilitation of its patients. Various attempts have been made to produce protective footwear such as the microcellular rubber-car-tyre sandals. Unfortunately these attempts have had little success on a large scale because of the inability to produce them in large numbers and the stigma attached to such unusual footwear. While such footwear may be superior to the 'tennis' shoe in protecting the foot from injury by the penetration of sharp objects, it fails to distribute the weight-bearing forces which is the major cause of plantar damage and ulceration in the anaesthetic foot. This can be achieved by providing rigidity to the sole, as demonstrated by the healing of ulcers in plaster of paris casts or the rigid wooden clog. A new type of moulded plastic footwear has been evolved in conjunction with the plastic footwear industry which provides footwear that can be mass produced at a low price and which overcomes the stigma of leprosy. Controlled rigidity is provided by the incorporation of a spring steel shank between the sponge insole and the hard wearing plastic sole. Trials have demonstrated both the acceptability of the footwear and its protective effects as well as its hard wearing properties.

  19. Lightweight concrete with Algerian limestone dust: Part I: Study on 30% replacement to normal aggregate at early age

    Directory of Open Access Journals (Sweden)

    S. Kitouni

    2013-12-01

    Full Text Available The mechanical characteristics of the lightweight aggregate concretes (LWAC strongly depend on the proportions of aggregates in the formulation. In particular, because of their strong porosity, the lightweight aggregates are much more deformable than the cementations matrix and their influence on concrete strength is complex. This paper focuses on studying the physical performance of concrete formulated with substitution of 30% of coarse aggregates by limestone dust. In this article an attempt is made to provide information on the elastic properties of lightweight concrete (LWC from tests carried out under uniaxial compression conditions. The results of Young modulus, Poisson's ratio, and compressive and flexural tensile strength tests on concrete are presented. The concretes obtained present good mechanical performances reaching 34.99 MPa compressive strength, 6.39 MPa flexural tensile strength and in front of 36 MPa Young modulus.

  20. Lightweight SIP/SDP compression scheme (LSSCS)

    Science.gov (United States)

    Wu, Jian J.; Demetrescu, Cristian

    2001-10-01

    In UMTS new IP based services with tight delay constraints will be deployed over the W-CDMA air interface such as IP multimedia and interactive services. To integrate the wireline and wireless IP services, 3GPP standard forum adopted the Session Initiation Protocol (SIP) as the call control protocol for the UMTS Release 5, which will implement next generation, all IP networks for real-time QoS services. In the current form the SIP protocol is not suitable for wireless transmission due to its large message size which will need either a big radio pipe for transmission or it will take far much longer to transmit than the current GSM Call Control (CC) message sequence. In this paper we present a novel compression algorithm called Lightweight SIP/SDP Compression Scheme (LSSCS), which acts at the SIP application layer and therefore removes the information redundancy before it is sent to the network and transport layer. A binary octet-aligned header is added to the compressed SIP/SDP message before sending it to the network layer. The receiver uses this binary header as well as the pre-cached information to regenerate the original SIP/SDP message. The key features of the LSSCS compression scheme are presented in this paper along with implementation examples. It is shown that this compression algorithm makes SIP transmission efficient over the radio interface without losing the SIP generality and flexibility.

  1. Chlorinated drinking water for lightweight laying hens

    Directory of Open Access Journals (Sweden)

    A.F. Schneider

    Full Text Available ABSTRACT The study aimed to evaluate the effect of different levels of chlorine in drinking water of laying hens on zootechnical performance, eggs shell quality, hemogasometry levels and calcium content in tibia. 144 Hy-Line laying hens, 61 weeks old, were used distributed in 24 metabolism cages. They were subjected to water diets, for a period of 28 days, using sodium hypochlorite as a chlorine source in order to obtain the following concentrations: 5ppm (control, 20ppm, 50ppm, and 100ppm. Their performance was evaluated through water consumption, feed intake, egg production and weight, egg mass, feed conversion. Shell quality was measured by specific gravity. At the end of the experiment, arterial blood was collected for blood gas level assessment and a poultry of each replicate was sacrificed to obtain tibia and calcium content measurement. There was a water consumption reduction from 20ppm of chlorine and feed intake reduction in poultry receiving water with 100ppm of chlorine. The regression analysis showed that the higher the level of chlorine in water, the higher the reduction in consumption. There were no differences in egg production and weight, egg mass, feed conversion, specific gravity, tibia calcium content, and hemogasometry levels (hydrogenionic potential, carbon dioxide partial pressure, oxygen partial pressure, sodium, potassium, chloride, bicarbonate, carbon dioxide total concentration, anion gap and oxygen saturation. The use of levels above 5ppm of chlorine is not recommended in the water of lightweight laying hens.

  2. Lightweight Solar Power for Small Satellites

    Science.gov (United States)

    Nabors, Sammy A.

    2015-01-01

    The innovation targets small satellites or CubeSats for which conventional deployable arrays are not feasible due to their size, weight and complexity. This novel solar cell array includes a thin and flexible photovoltaic cell applied to an inflatable structure to create a high surface area array for collecting solar energy in a lightweight, simple and deployable structure. The inflatable array, with its high functional surface area, eliminates the need and the mechanisms required to point the system toward the sun. The power density achievable in these small arrays is similar to that of conventional high-power deployable/pointable arrays used on large satellites or space vehicles. Although inflatable solar arrays have been previously considered by others, the arrays involved the use of traditional rigid solar cells. Researchers are currently working with thin film photovoltaics from various suppliers so that the NASA innovation is not limited to any particular solar cell technology. NASA has built prototypes and tested functionality before and after inflation. As shown in the current-voltage currents below, deployment does not damage the cell performance.

  3. Warm Hydroforming of Lightweight Metal Sheets

    International Nuclear Information System (INIS)

    Aginagalde, A.; Orus, A.; Esnaola, J. A.; Torca, I.; Galdos, L.; Garcia, C.

    2007-01-01

    Hydroforming is well known in steel applications for automotive industry, where complicated shapes can be get with high strength to weight ratios. Nevertheless, the poor formability of light alloys at room temperature has limited the application of hydroforming technology for aluminum and magnesium parts. Increasing the temperature of these materials allows substantially greater elongation without fracture. Warm forming strategy is applied in conventional processes, such as rolling and forging, in order to get complex shapes, but still rare in hydroforming technology. This is the technical base of this research project: the development of the hydroforming process at warm working temperatures. The main tasks of the initial phases of the research were the material characterization, and the heated fluid and tooling system design and set up for warm hydroforming of lightweight alloys. Once these goals were accomplished the present paper shows the obtained results. The uniaxial tensile deformation of 5754H111, 6082-T6, 6082-O and AZ31B at the temperature range of 25 deg. C - 250 deg. C is presented as the output of the material characterization task. Both the system features and the results obtained for a bulge test geometry carried out with a warm hydroforming system are also presented. The selected alloys show an improvement in formability at the studied temperature range under both uniaxial and biaxial state of stress

  4. Abstracting audit data for lightweight intrusion detection

    KAUST Repository

    Wang, Wei

    2010-01-01

    High speed of processing massive audit data is crucial for an anomaly Intrusion Detection System (IDS) to achieve real-time performance during the detection. Abstracting audit data is a potential solution to improve the efficiency of data processing. In this work, we propose two strategies of data abstraction in order to build a lightweight detection model. The first strategy is exemplar extraction and the second is attribute abstraction. Two clustering algorithms, Affinity Propagation (AP) as well as traditional k-means, are employed to extract the exemplars, and Principal Component Analysis (PCA) is employed to abstract important attributes (a.k.a. features) from the audit data. Real HTTP traffic data collected in our institute as well as KDD 1999 data are used to validate the two strategies of data abstraction. The extensive test results show that the process of exemplar extraction significantly improves the detection efficiency and has a better detection performance than PCA in data abstraction. © 2010 Springer-Verlag.

  5. Experimental Study on Fatigue Performance of Foamed Lightweight Soil

    Science.gov (United States)

    Qiu, Youqiang; Yang, Ping; Li, Yongliang; Zhang, Liujun

    2017-12-01

    In order to study fatigue performance of foamed lightweight soil and forecast its fatigue life in the supporting project, on the base of preliminary tests, beam fatigue tests on foamed lightweight soil is conducted by using UTM-100 test system. Based on Weibull distribution and lognormal distribution, using the mathematical statistics method, fatigue equations of foamed lightweight soil are obtained. At the same time, according to the traffic load on real road surface of the supporting project, fatigue life of formed lightweight soil is analyzed and compared with the cumulative equivalent axle loads during the design period of the pavement. The results show that even the fatigue life of foamed lightweight soil has discrete property, the linear relationship between logarithmic fatigue life and stress ratio still performs well. Especially, the fatigue life of Weibull distribution is more close to that derived from the lognormal distribution, in the instance of 50% guarantee ratio. In addition, the results demonstrated that foamed lightweight soil as subgrade filler has good anti-fatigue performance, which can be further adopted by other projects in the similar research domain.

  6. Analytical design model for a piezo-composite unimorph actuator and its verification using lightweight piezo-composite curved actuators

    Science.gov (United States)

    Yoon, K. J.; Park, K. H.; Lee, S. K.; Goo, N. S.; Park, H. C.

    2004-06-01

    This paper describes an analytical design model for a layered piezo-composite unimorph actuator and its numerical and experimental verification using a LIPCA (lightweight piezo-composite curved actuator) that is lighter than other conventional piezo-composite type actuators. The LIPCA is composed of top fiber composite layers with high modulus and low CTE (coefficient of thermal expansion), a middle PZT ceramic wafer, and base layers with low modulus and high CTE. The advantages of the LIPCA design are to replace the heavy metal layer of THUNDER by lightweight fiber-reinforced plastic layers without compromising the generation of high force and large displacement and to have design flexibility by selecting the fiber direction and the number of prepreg layers. In addition to the lightweight advantage and design flexibility, the proposed device can be manufactured without adhesive layers when we use a resin prepreg system. A piezo-actuation model for a laminate with piezo-electric material layers and fiber composite layers is proposed to predict the curvature and residual stress of the LIPCA. To predict the actuation displacement of the LIPCA with curvature, a finite element analysis method using the proposed piezo-actuation model is introduced. The predicted deformations are in good agreement with the experimental ones.

  7. 49 CFR 192.321 - Installation of plastic pipe.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Installation of plastic pipe. 192.321 Section 192... Transmission Lines and Mains § 192.321 Installation of plastic pipe. (a) Plastic pipe must be installed below ground level except as provided by paragraphs (g) and (h) of this section. (b) Plastic pipe that is...

  8. Introduction to Computational Plasticity

    International Nuclear Information System (INIS)

    Hartley, P

    2006-01-01

    The focus of the book on computational plasticity embodies techniques of relevance not only to academic researchers, but also of interest to industrialists engaged in the production of components using bulk or sheet forming processes. Of particular interest is the guidance on how to create modules for use with the commercial system Abaqus for specific types of material behaviour. The book is in two parts, the first of which contains six chapters, starting with microplasticity, but predominantly on continuum plasticity. The first chapter on microplasticty gives a brief description of the grain structure of metals and the existence of slip systems within the grains. This provides an introduction to the concept of incompressibility during plastic deformation, the nature of plastic yield and the importance of the critically resolved shear stress on the slip planes (Schmid's law). Some knowledge of the notation commonly used to describe slip systems is assumed, which will be familiar to students of metallurgy, but anyone with a more general engineering background may need to undertake additional reading to understand the various descriptions. Chapter two introduces one of several yield criteria, that normally attributed to von Mises (though historians of mechanics might argue over who was first to develop the theory of yielding associated with strain energy density), and its two or three-dimensional representation as a yield surface. The expansion of the yield surface during plastic deformation, its translation due to kinematic hardening and the Bauschinger effect in reversed loading are described with a direct link to the material stress-strain curve. The assumption, that the increment of strain is normal to the yield surface, the normality principle, is introduced. Uniaxial loading of an elastic-plastic material is used as an example in which to develop expressions to describe increments in stress and strain. The full presentation of numerous expressions, tensors and

  9. Argobots: A Lightweight Low-Level Threading and Tasking Framework

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Sangmin; Amer, Abdelhalim; Balaji, Pavan; Bordage, Cyril; Bosilca, George; Brooks, Alex; Carns, Philip; Castello, Adrian; Genet, Damien; Herault, Thomas; Iwasaki, Shintaro; Jindal, Prateek; Kale, Laxmikant V.; Krishnamoorthy, Sriram; Lifflander, Jonathan; Lu, Huiwei; Meneses, Esteban; Snir, Marc; Sun, Yanhua; Taura, Kenjiro; Beckman, Pete

    2018-03-01

    In the past few decades, a number of user-level threading and tasking models have been proposed in the literature to address the shortcomings of OS-level threads, primarily with respect to cost and flexibility. Current state-of-the-art user-level threading and tasking models, however, either are too specific to applications or architectures or are not as powerful or flexible. In this paper, we present Argobots, a lightweight, low-level threading and tasking framework that is designed as a portable and performant substrate for high-level programming models or runtime systems. Argobots offers a carefully designed execution model that balances generality of functionality with providing a rich set of controls to allow specialization by end users or high-level programming models. We describe the design, implementation, and performance characterization of Argobots and present integrations with three high-level models: OpenMP, MPI, and colocated I/O services. Evaluations show that (1) Argobots, while providing richer capabilities, is competitive with existing simpler generic threading runtimes; (2) our OpenMP runtime offers more efficient interoperability capabilities than production OpenMP runtimes do; (3) when MPI interoperates with Argobots instead of Pthreads, it enjoys reduced synchronization costs and better latency-hiding capabilities; and (4) I/O services with Argobots reduce interference with colocated applications while achieving performance competitive with that of a Pthreads approach.

  10. Innovative lightweight substrate for stable optical benches and mirrors

    Science.gov (United States)

    Rugi Grond, E.; Herren, A.; Mérillat, S.; Fermé, J. J.

    2017-11-01

    High precision space optics, such as spectrometers, relay optics, and filters, require ultra stable, lightweight platforms. These equipped platforms have on one side to survive the launch loads, on the other side they have to maintain their stability also under the varying thermal loads occurring in space. Typically such platforms have their equipment (prisms, etalons, beam expanders, etc.) mounted by means of classical bonding, hydro-catalytic bonding or optical contacting. Therefore such an optical bench requires to provide an excellent flatness, minimal roughness and is usually made of the same material as the equipment it carries (glass, glass ceramics). For space systems, mass is a big penalty, therefore such optical platforms are in most cases light weighted by means of machining features (i.e. pockets). Besides of being not extremely mass efficient, such pockets reduce the load carrying capability of the base material significantly. The challenge for Oerlikon Space, in this context, was to develop, qualify and deliver such optical benches, providing a substantial mass reduction compared to actual light weighted systems, while maintaining most of the full load carrying capacity of the base material. Additionally such a substrate can find an attractive application for mirror substrates. The results of the first development and of the first test results will be presented.

  11. Plasticity modeling & computation

    CERN Document Server

    Borja, Ronaldo I

    2013-01-01

    There have been many excellent books written on the subject of plastic deformation in solids, but rarely can one find a textbook on this subject. “Plasticity Modeling & Computation” is a textbook written specifically for students who want to learn the theoretical, mathematical, and computational aspects of inelastic deformation in solids. It adopts a simple narrative style that is not mathematically overbearing, and has been written to emulate a professor giving a lecture on this subject inside a classroom. Each section is written to provide a balance between the relevant equations and the explanations behind them. Where relevant, sections end with one or more exercises designed to reinforce the understanding of the “lecture.” Color figures enhance the presentation and make the book very pleasant to read. For professors planning to use this textbook for their classes, the contents are sufficient for Parts A and B that can be taught in sequence over a period of two semesters or quarters.

  12. Effect of presaturation and seawater on strength and durability of lightweight concrete

    International Nuclear Information System (INIS)

    Haque, M.N.

    2009-01-01

    The internal curing is provided, usually, by the use of some proprietary fine aggregates which provide sufficient water from within to promote the ongoing hydration of cement and hence result in a relatively high performance concrete. Two concretes, one total lightweight concrete (TLWC) and the second sand lightweight concrete (SLWC) of 28 day cube strength of approximately 40 MPa (5800 psi) were designed. A total of six mixes were cast out of these two concretes, 4-TLWC's and 2-SLWC's. The variation in the mixes was due to moisture condition of the aggregates and the use of seawater in mixing and curing of the concretes. The effect of these variations on the cube compressive strength, water permeability, sulphate and chloride content, depth of carbonation and shrinkage of these six concretes was studied. The presaturation of the lightweight aggregates (LWA's used do not seem to have improved the compressive strength, and water permeability of these concretes. The drying shrinkage strains of the concrete using pre saturated aggregates decreased considerably. The application of seawater in making and curing these LWC's increased the compressive strength by about 15%. (author)

  13. From macro- to microplastics - Analysis of EU regulation along the life cycle of plastic bags

    DEFF Research Database (Denmark)

    Steensgaard, Ida M; Syberg, Kristian; Rist, Sinja

    2017-01-01

    Plastic pollution and its environmental effects has received global attention the recent years. However, limited attention has so far been directed towards how plastics are regulated in a life cycle perspective and how regulatory gaps can be addressed in order to limit and prevent environmental...... exposure and hazards of macro- and microplastics. In this paper, we map European regulation taking outset in the life cycle perspective of plastic carrier bags: from plastic bag production to when it enters the environment. Relevant regulatory frameworks, directives and authorities along the life cycle...... are identified and their role in regulation of plastics is discussed. Most important regulations were identified as: the EU chemical Regulation, the Packaging and Packaging Waste Directive including the amending Directive regarding regulation of the consumption of lightweight plastic carrier bags, the Waste...

  14. A lightweight, biological structure with tailored stiffness: The feather vane.

    Science.gov (United States)

    Sullivan, Tarah N; Pissarenko, Andreï; Herrera, Steven A; Kisailus, David; Lubarda, Vlado A; Meyers, Marc A

    2016-09-01

    The flying feathers of birds are keratinous appendages designed for maximum performance with a minimum weight penalty. Thus, their design contains ingenious combinations of components that optimize lift, stiffness, aerodynamics, and damage resistance. This design involves two main parts: a central shaft that prescribes stiffness and lateral vanes which allows for the capture of air. Within the feather vane, barbs branch from the shaft and barbules branch from barbs, forming a flat surface which ensures lift. Microhooks at the end of barbules hold barbs tightly together, providing the close-knit, unified structure of the feather vane and enabling a repair of the structure through the reattachment of un-hooked junctions. Both the shaft and barbs are lightweight biological structures constructed of keratin using the common motif of a solid shell and cellular interior. The cellular core increases the resistance to buckling with little added weight. Here we analyze the detailed structure of the feather barb and, for the first time, explain its flexural stiffness in terms of the mechanics of asymmetric foam-filled beams subjected to bending. The results are correlated and validated with finite element modeling. We compare the flexure of single barbs as well as arrays of barbs and find that the interlocking adherence of barbs to one another enables a more robust structure due to minimized barb rotation during deflection. Thus, the flexure behavior of the feather vane can be tailored by the adhesive hooking between barbs, creating a system that mitigates damage. A simplified three-dimensional physical model for this interlocking mechanism is constructed by additive manufacturing. The exceptional architecture of the feather vane will motivate the design of bioinspired structures with tailored and unique properties ranging from adhesives to aerospace materials. Despite its importance to bird flight, literature characterizing the feather vane is extremely limited. The feather

  15. Recycling of Plastic

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Fruergaard, Thilde

    2011-01-01

    Plastic is produced from fossil oil. Plastic is used for many different products. Some plastic products like, for example, wrapping foil, bags and disposable containers for food and beverage have very short lifetimes and thus constitute a major fraction of most waste. Other plastic products like...

  16. Challenges and Alternatives to Plastics Recycling in the Automotive Sector

    Directory of Open Access Journals (Sweden)

    Lindsay Miller

    2014-08-01

    Full Text Available Plastics are increasingly a preferred material choice in designing and developing complex, consumer products, such as automobiles, because they are mouldable, lightweight, and are often perceived to be highly recyclable materials. However, actually recycling the heterogeneous plastics used in such durable items is challenging, and presents very different scenarios to how simple products, such as water bottles, are recovered via curbside or container recycling initiatives. While the technology exists to recycle plastics, their feasibility to do so from high level consumer or industrial applications is bounded by technological and economical restraints. Obstacles include the lack of market for recyclates, and the lack of cost efficient recovery infrastructures or processes. Furthermore, there is a knowledge gap between manufacturers, consumers, and end-of-life facility operators. For these reasons, end-of-life plastics are more likely to end up down-cycled, or as shredder residue and then landfilled. This paper reviews these challenges and several alternatives to recycling plastics in order to broaden the mindset surrounding plastics recycling to improve their sustainability. The paper focuses on the automotive sector for examples, but discussion can be applied to a wide range of plastic components from similarly complex products.

  17. Challenges and Alternatives to Plastics Recycling in the Automotive Sector

    Science.gov (United States)

    Miller, Lindsay; Soulliere, Katie; Sawyer-Beaulieu, Susan; Tseng, Simon; Tam, Edwin

    2014-01-01

    Plastics are increasingly a preferred material choice in designing and developing complex, consumer products, such as automobiles, because they are mouldable, lightweight, and are often perceived to be highly recyclable materials. However, actually recycling the heterogeneous plastics used in such durable items is challenging, and presents very different scenarios to how simple products, such as water bottles, are recovered via curbside or container recycling initiatives. While the technology exists to recycle plastics, their feasibility to do so from high level consumer or industrial applications is bounded by technological and economical restraints. Obstacles include the lack of market for recyclates, and the lack of cost efficient recovery infrastructures or processes. Furthermore, there is a knowledge gap between manufacturers, consumers, and end-of-life facility operators. For these reasons, end-of-life plastics are more likely to end up down-cycled, or as shredder residue and then landfilled. This paper reviews these challenges and several alternatives to recycling plastics in order to broaden the mindset surrounding plastics recycling to improve their sustainability. The paper focuses on the automotive sector for examples, but discussion can be applied to a wide range of plastic components from similarly complex products. PMID:28788167

  18. Towards a Certified Lightweight Array Bound Checker for Java Bytecode

    Science.gov (United States)

    Pichardie, David

    2009-01-01

    Dynamic array bound checks are crucial elements for the security of a Java Virtual Machines. These dynamic checks are however expensive and several static analysis techniques have been proposed to eliminate explicit bounds checks. Such analyses require advanced numerical and symbolic manipulations that 1) penalize bytecode loading or dynamic compilation, 2) complexify the trusted computing base. Following the Foundational Proof Carrying Code methodology, our goal is to provide a lightweight bytecode verifier for eliminating array bound checks that is both efficient and trustable. In this work, we define a generic relational program analysis for an imperative, stackoriented byte code language with procedures, arrays and global variables and instantiate it with a relational abstract domain as polyhedra. The analysis has automatic inference of loop invariants and method pre-/post-conditions, and efficient checking of analysis results by a simple checker. Invariants, which can be large, can be specialized for proving a safety policy using an automatic pruning technique which reduces their size. The result of the analysis can be checked efficiently by annotating the program with parts of the invariant together with certificates of polyhedral inclusions. The resulting checker is sufficiently simple to be entirely certified within the Coq proof assistant for a simple fragment of the Java bytecode language. During the talk, we will also report on our ongoing effort to scale this approach for the full sequential JVM.

  19. ARC Cache: A solution for lightweight Grid sites in ATLAS

    CERN Document Server

    Garonne, Vincent; The ATLAS collaboration

    2016-01-01

    Many Grid sites have the need to reduce operational manpower, and running a storage element consumes a large amount of effort. In addition, setting up a new Grid site including a storage element involves a steep learning curve and large investment of time. For these reasons so-called storage-less sites are becoming more popular as a way to provide Grid computing resources with less operational overhead. ARC CE is a widely-used and mature Grid middleware which was designed from the start to be used on sites with no persistent storage element. Instead, it maintains a local self-managing cache of data which retains popular data for future jobs. As the cache is simply an area on a local posix shared filesystem with no external-facing service, it requires no extra maintenance. The cache can be scaled up as required by increasing the size of the filesystem or adding new filesystems. This paper describes how ARC CE and its cache are an ideal solution for lightweight Grid sites in the ATLAS experiment, and the integr...

  20. Argobots: A Lightweight Low-Level Threading and Tasking Framework

    International Nuclear Information System (INIS)

    Seo, Sangmin; Amer, Abdelhalim; Balaji, Pavan; Bordage, Cyril; Bosilca, George

    2017-01-01

    In the past few decades, a number of user-level threading and tasking models have been proposed in the literature to address the shortcomings of OS-level threads, primarily with respect to cost and flexibility. Current state-of-the-art user-level threading and tasking models, however, are either too specific to applications or architectures or are not as powerful or flexible. In this article, we present Argobots, a lightweight, low-level threading and tasking framework that is designed as a portable and performant substrate for high-level programming models or runtime systems. Argobots offers a carefully designed execution model that balances generality of functionality with providing a rich set of controls to allow specialization by the user or high-level programming model. Here, we describe the design, implementation, and optimization of Argobots and present integrations with three example high-level models: OpenMP, MPI, and co-located I/O service. Evaluations show that (1) Argobots outperforms existing generic threading runtimes; (2) our OpenMP runtime offers more efficient interoperability capabilities than production OpenMP runtimes do; (3) when MPI interoperates with Argobots instead of Pthreads, it enjoys reduced synchronization costs and better latency hiding capabilities; and (4) I/O service with Argobots reduces interference with co-located applications, achieving performance competitive with that of the Pthreads version.

  1. Mechanical, Thermal and Functional Properties of Green Lightweight Foamcrete

    Directory of Open Access Journals (Sweden)

    Md Azree Othuman Mydin

    2012-09-01

    Full Text Available In recent times, the construction industry has revealed noteworthy attention in the use of lightweight foamcrete as a building material due to its many favourable characteristics such as lighter weight, easy to fabricate, durable and cost effective. Foamcrete is a material consisting of Portland cement paste or cement filler matrix (mortar with a homogeneous pore structure created by introducing air in the form of small bubbles. With a proper control in dosage of foam and methods of production, a wide range of densities (400 – 1600 kg/m 3 of foamcrete can be produced thus providing flexibility for application such as structural elements, partition, insulating materials and filling grades. Foamcrete has so far been applied primarily as a filler material in civil engineering works. However, its good thermal and acoustic performance indicates its strong potential as a material in building construction. The focus of this paper is to classify literature on foamcrete in terms of its mechanical, thermal and functional properties.

  2. Abstracting massive data for lightweight intrusion detection in computer networks

    KAUST Repository

    Wang, Wei

    2016-10-15

    Anomaly intrusion detection in big data environments calls for lightweight models that are able to achieve real-time performance during detection. Abstracting audit data provides a solution to improve the efficiency of data processing in intrusion detection. Data abstraction refers to abstract or extract the most relevant information from the massive dataset. In this work, we propose three strategies of data abstraction, namely, exemplar extraction, attribute selection and attribute abstraction. We first propose an effective method called exemplar extraction to extract representative subsets from the original massive data prior to building the detection models. Two clustering algorithms, Affinity Propagation (AP) and traditional . k-means, are employed to find the exemplars from the audit data. . k-Nearest Neighbor (k-NN), Principal Component Analysis (PCA) and one-class Support Vector Machine (SVM) are used for the detection. We then employ another two strategies, attribute selection and attribute extraction, to abstract audit data for anomaly intrusion detection. Two http streams collected from a real computing environment as well as the KDD\\'99 benchmark data set are used to validate these three strategies of data abstraction. The comprehensive experimental results show that while all the three strategies improve the detection efficiency, the AP-based exemplar extraction achieves the best performance of data abstraction.

  3. A Lightweight Anonymous Authentication Protocol with Perfect Forward Secrecy for Wireless Sensor Networks.

    Science.gov (United States)

    Xiong, Ling; Peng, Daiyuan; Peng, Tu; Liang, Hongbin; Liu, Zhicai

    2017-11-21

    Due to their frequent use in unattended and hostile deployment environments, the security in wireless sensor networks (WSNs) has attracted much interest in the past two decades. However, it remains a challenge to design a lightweight authentication protocol for WSNs because the designers are confronted with a series of desirable security requirements, e.g., user anonymity, perfect forward secrecy, resistance to de-synchronization attack. Recently, the authors presented two authentication schemes that attempt to provide user anonymity and to resist various known attacks. Unfortunately, in this work we shall show that user anonymity of the two schemes is achieved at the price of an impractical search operation-the gateway node may search for every possible value. Besides this defect, they are also prone to smart card loss attacks and have no provision for perfect forward secrecy. As our main contribution, a lightweight anonymous authentication scheme with perfect forward secrecy is designed, and what we believe the most interesting feature is that user anonymity, perfect forward secrecy, and resistance to de-synchronization attack can be achieved at the same time. As far as we know, it is extremely difficult to meet these security features simultaneously only using the lightweight operations, such as symmetric encryption/decryption and hash functions.

  4. Biopolymer Doped with Titanium Dioxide Superhydrophobic Photocatalysis as Self-Clean Coating for Lightweight Composite

    Directory of Open Access Journals (Sweden)

    Anika Zafiah M. Rus

    2013-01-01

    Full Text Available The development of a lightweight composite (LC based on Portland cement concrete with waste lightweight aggregate (WLA additive was carried out to improve the sustainability and environmental impact and to offer potential cost savings without sacrificing strength. Treatment of the surface of the LC exposed to environmental attack by coating with biopolymer based on waste cooking oil doped with titanium dioxide photocatalysis (TOP with superhydrophilic property was found to affect the mechanical properties of the LC in a systematic way. The results of compressive strength showed that the composite achieved the minimum required strength for lightweight construction materials of 17.2 MPa. Scratch resistance measurements showed that the highest percentages loading of superhydrophilic particles (up to 2.5% of biomonomer weight for LC's surface coating gave the highest scratch resistance while the uncoated sample showed the least resistances. Scanning electron microscope (SEM pictures revealed the difference between the surface roughness for LC with and without TOP coating. TOP is also formulated to provide self-cleaning LC surfaces based on two principal ways: (1 the development by coating the LC with a photocatalytic superhydrophilic, (2 if such a superhydrophilic is illuminated by light, the grease, dirt, and organic contaminants will be decomposed and can easily be swept away by rain.

  5. A Lightweight Anonymous Authentication Protocol with Perfect Forward Secrecy for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Ling Xiong

    2017-11-01

    Full Text Available Due to their frequent use in unattended and hostile deployment environments, the security in wireless sensor networks (WSNs has attracted much interest in the past two decades. However, it remains a challenge to design a lightweight authentication protocol for WSNs because the designers are confronted with a series of desirable security requirements, e.g., user anonymity, perfect forward secrecy, resistance to de-synchronization attack. Recently, the authors presented two authentication schemes that attempt to provide user anonymity and to resist various known attacks. Unfortunately, in this work we shall show that user anonymity of the two schemes is achieved at the price of an impractical search operation—the gateway node may search for every possible value. Besides this defect, they are also prone to smart card loss attacks and have no provision for perfect forward secrecy. As our main contribution, a lightweight anonymous authentication scheme with perfect forward secrecy is designed, and what we believe the most interesting feature is that user anonymity, perfect forward secrecy, and resistance to de-synchronization attack can be achieved at the same time. As far as we know, it is extremely difficult to meet these security features simultaneously only using the lightweight operations, such as symmetric encryption/decryption and hash functions.

  6. Production of lightweight refractory material by hydrothermal process

    International Nuclear Information System (INIS)

    Sulejmani, Ramiz B.

    2002-01-01

    Many different processes of production of lightweight refractories are well known over the World. Traditional production of lightweight refractories is by addition of combustibles or by a special frothing process. This work is concerned with hydrothermal of lightweight refractories from rice husk ash. The rice husk ash, used in present investigations were from Kocani region, R. Macedonia. The chemical analysis of the rice husk ash shows that it contains 91,8 - 93,7% SiO 2 and some alkaline and alkaline earth oxides. Microscopic and X - ray diffraction examinations of the rice husk ash have shown that it is composed of cristobalite, tridimite and amorphous silica. The composition of the mixture for lightweight refractory brick production is 93,4% rice husk ash and 6,6% Ca(OH) 2 . The mixtures were well mixed, moistened and pressed at 5 - 10 MPa. The hydrothermal reactions between calcium hydroxide and rice husk ash over the temperature range 80 - 160 o C were investigated. The period of autoclave treatment was from 2 to 72 h. After the hydrothermal treatment of the samples, the mineralogical composition, bulk density, density, cold crushing strength, porosity, refractoriness and thermal expansion were examined. Analysing the properties of the obtained samples it can be concluded that from rice husk ash and calcium hydroxide under hydrothermal condition it is possible to obtain lightweight acid refractory material with high quality.(Author)

  7. Modeling of the plastic flow kinematics in the forming process of the lightweight flange corrugation

    Directory of Open Access Journals (Sweden)

    I. V. Fomenko

    2012-01-01

    Full Text Available The determination of the forming maximum possibilities of the flange corrugation by stretching with a free movement of the billets end in the rigid sectional matrices detachable by the flexible filler.

  8. Intentional Planning to Provide Technology to Students

    Science.gov (United States)

    Flagg-Williams, Joan B.; Rey, Janice M.

    2016-01-01

    Mobile technology plays a prominent role in teaching and learning. To address this vital component of teacher preparation, the education department of a small college provided the freshman class with iPads. iPads were selected because they are common in public schools, lightweight, portable, touch-screen controlled and have an abundance of…

  9. Permeation barrier for lightweight liquid hydrogen tanks

    Energy Technology Data Exchange (ETDEWEB)

    Schultheiss, D.

    2007-04-16

    For the future usage of hydrogen as an automotive fuel, its on-board storage is crucial. One approach is the storage of liquid hydrogen (LH2, 20 K) in double-walled, vacuum insulated tanks. The introduction of carbon fiber reinforced plastics (CFRP) as structural material enables a high potential of reducing the weight in comparison to the state-of-the-art stainless steel tanks. The generally high permeability of hydrogen through plastics, however, can lead to long-term degradation of the insulating vacuum. The derived objective of this dissertation was to find and apply an adequate permeation barrier (liner) on CFRP. The investigated liners were either foils adhered on CFRP specimens or coatings deposited on CFRP specimens. The coatings were produced by means of thermal spraying, metal plating or physical vapor deposition (PVD). The materials of the liners included Al, Au, Cu, Ni and Sn as well as stainless steel and diamond-like carbon. The produced liners were tested for their permeation behavior, thermal shock resistance and adherence to the CFRP substrate. Additionally, SEM micrographs were used to characterize and qualify the liners. The foils, although being a good permeation barrier, adhered weakly to the substrate. Furthermore, leak-free joining of foil segments is a challenge still to be solved. The metal plating liners exhibited the best properties. For instance, no permeation could be detected through a 50 {mu}m thick Cu coating within the accuracy of the measuring apparatus. This corresponds to a reduction of the permeation gas flow by more than factor 7400 compared to uncoated CFRP. In addition, the metal platings revealed a high adherence and thermal shock resistance. The coatings produced by means of thermal spraying and PVD did not show a sufficient permeation barrier effect. After having investigated the specimens, a 170 liter CFRP tank was fully coated with 50 {mu}m Cu by means of metal plating. (orig.)

  10. Lightweight acoustic treatments for aerospace applications

    Science.gov (United States)

    Naify, Christina Jeanne

    2011-12-01

    Increase in the use of composites for aerospace applications has the benefit of decreased structural weight, but at the cost of decreased acoustic performance. Stiff, lightweight structures (such as composites) are traditionally not ideal for acoustic insulation applications because of high transmission loss at low frequencies. A need has thus arisen for effective sound insulation materials for aerospace and automotive applications with low weight addition. Current approaches, such as the addition of mass law dominated materials (foams) also perform poorly when scaled to small thickness and low density. In this dissertation, methods which reduce sound transmission without adding significant weight are investigated. The methods presented are intended to be integrated into currently used lightweight structures such as honeycomb sandwich panels and to cover a wide range of frequencies. Layering gasses of differing acoustic impedances on a panel substantially reduced the amount of sound energy transmitted through the panel with respect to the panel alone or an equivalent-thickness single species gas layer. The additional transmission loss derives from successive impedance mismatches at the interfaces between gas layers and the resulting inefficient energy transfer. Attachment of additional gas layers increased the transmission loss (TL) by as much as 17 dB at high (>1 kHz) frequencies. The location and ordering of the gasses with respect to the panel were important factors in determining the magnitude of the total TL. Theoretical analysis using a transfer matrix method was used to calculate the frequency dependence of sound transmission for the different configurations tested. The method accurately predicted the relative increases in TL observed with the addition of different gas layer configurations. To address low-frequency sound insulation, membrane-type locally resonant acoustic materials (LRAM) were fabricated, characterized, and analyzed to understand their

  11. Durability of Geopolymer Lightweight Concrete Infilled LECA in Seawater Exposure

    Science.gov (United States)

    Razak, R. A.; Abdullah, M. M. A. B.; Yahya, Z.; Hamid, M. S. A.

    2017-11-01

    This paper describes a development of lightweight concrete using lightweight expanded clay aggregate (LECA) in fly ash (FA) based geopolymer immersed in seawater. The objective of this research is to compare the performance of geopolymer concrete (GPC) with ordinary Portland cement (OPC) concrete infilled lightweight expanded clay aggregate (LECA) in seawater exposure. Geopolymer concrete is produced by using alkaline activator to activate the raw material, FA. The highest compressive strength of this study is 42.0 MPa at 28 days and 49.8 MPa at 60 days. The density for this concrete is in the range of 1580 kg/m3 to 1660 kg/m3. The result for water absorption is in the range of 6.82% to 14.72%. However, the test results of weight loss is in the range between 0.30% to 0.43%.

  12. Light-weight Mutual Authentication with Non-repudiation

    Directory of Open Access Journals (Sweden)

    V. Clupek

    2018-04-01

    Full Text Available In this paper, we focused on a problem of authentication on low-cost devices. We have proposed a new light-weight protocol for mutual authentication of communication entities with non-repudiation of realized events. The protocol is simple and suitable for implementation on low-cost devices. Non-repudiation of realized events is achieved by involving a Trusted Third Party (TTP to the communication. The proposed protocol uses only an appropriate lightweight hash function and pre-shared secret data. Security of the proposed protocol was verified by the BAN (Burrows-Abadi-Needham logic.

  13. A Review on the Use of Agriculture Waste Material as Lightweight Aggregate for Reinforced Concrete Structural Members

    Directory of Open Access Journals (Sweden)

    Kim Hung Mo

    2014-01-01

    Full Text Available The agriculture industry is one of the main industries in the Southeast Asia region due to its favourable conditions for plantations. In fact, Southeast Asia region is the world’s largest producer of palm oil and coconut. Nevertheless, vast plantation of these agriculture products leads to equally large amount of waste materials emanating from these industries. Previously, researchers have attempted to utilize the resulting waste materials such as oil palm shell, palm oil clinker, and coconut shell from these industries as lightweight aggregate to produce structural grade lightweight aggregate concrete. In order to promote the concept of using such concrete for actual structural applications, this paper reviews the use of such agriculture-based lightweight aggregate concrete in reinforced concrete structural members such as beam and slab, which were carried out by researchers in the past. The behaviour of the structural members under flexural, shear, and torsional load was also summarized. It is hoped that the knowledge attained from the paper will provide design engineers with better idea and proper application of design criteria for structural members using such agriculture waste as lightweight aggregate.

  14. Strength properties of cement slurries with lightweights applied in oil and gas wells

    International Nuclear Information System (INIS)

    Bubnov, A S; Drilling Mud and Cement Slurry (Russian Federation))" data-affiliation=" (Head of Laboratory Drilling Mud and Cement Slurry (Russian Federation))" >Boyko, I A; Drilling Mud and Cement Slurry (Russian Federation))" data-affiliation=" (PhD, Engineer, Laboratory Drilling Mud and Cement Slurry (Russian Federation))" >Khorev, V S

    2015-01-01

    The article is focused on the cement stone strength properties resulted from lightweight cement slurries that meet GOST-1581-96 (state Standards) requirements. Exfoliated vermiculite, hollow aluminosilicate microspheres (HAMs), diatomite and perlite were used as lightweighting additives

  15. Benthic plastic debris in marine and fresh water environments.

    Science.gov (United States)

    Corcoran, Patricia L

    2015-08-01

    This review provides a discussion of the published literature concerning benthic plastic debris in ocean, sea, lake, estuary and river bottoms throughout the world. Although numerous investigations of shoreline, surface and near-surface plastic debris provide important information on plastic types, distribution, accumulation, and degradation, studies of submerged plastic debris have been sporadic in the past and have become more prominent only recently. The distribution of benthic debris is controlled mainly by combinations of urban proximity and its association with fishing-related activities, geomorphology, hydrological conditions, and river input. High density plastics, biofouled products, polymers with mineral fillers or adsorbed minerals, and plastic-metal composites all have the potential to sink. Once deposited on the bottoms of water basins and channels, plastics are shielded from UV light, thus slowing the degradation process significantly. Investigations of the interactions between benthic plastic debris and bottom-dwelling organisms will help shed light on the potential dangers of submerged plastic litter.

  16. Wood-plastic combination

    International Nuclear Information System (INIS)

    Schaudy, R.

    1978-02-01

    A review on wood-plastic combinations is given including the production (wood and plastic component, radiation hardening, curing), the obtained properties, present applications and prospects for the future of these materials. (author)

  17. DESIGNERS’ KNOWLEDGE IN PLASTICS

    DEFF Research Database (Denmark)

    Eriksen, Kaare

    2013-01-01

    The Industrial designers’ knowledge in plastics materials and manufacturing principles of polymer products is very important for the innovative strength of the industry, according to a group of Danish plastics manufacturers, design students and practicing industrial designers. These three groups ...

  18. River plastic emissions to the world's oceans

    Science.gov (United States)

    Lebreton, Laurent C. M.; van der Zwet, Joost; Damsteeg, Jan-Willem; Slat, Boyan; Andrady, Anthony; Reisser, Julia

    2017-06-01

    Plastics in the marine environment have become a major concern because of their persistence at sea, and adverse consequences to marine life and potentially human health. Implementing mitigation strategies requires an understanding and quantification of marine plastic sources, taking spatial and temporal variability into account. Here we present a global model of plastic inputs from rivers into oceans based on waste management, population density and hydrological information. Our model is calibrated against measurements available in the literature. We estimate that between 1.15 and 2.41 million tonnes of plastic waste currently enters the ocean every year from rivers, with over 74% of emissions occurring between May and October. The top 20 polluting rivers, mostly located in Asia, account for 67% of the global total. The findings of this study provide baseline data for ocean plastic mass balance exercises, and assist in prioritizing future plastic debris monitoring and mitigation strategies.

  19. Lightweight Stacks of Direct Methanol Fuel Cells

    Science.gov (United States)

    Narayanan, Sekharipuram; Valdez, Thomas

    2004-01-01

    An improved design concept for direct methanol fuel cells makes it possible to construct fuel-cell stacks that can weigh as little as one-third as much as do conventional bipolar fuel-cell stacks of equal power. The structural-support components of the improved cells and stacks can be made of relatively inexpensive plastics. Moreover, in comparison with conventional bipolar fuel-cell stacks, the improved fuel-cell stacks can be assembled, disassembled, and diagnosed for malfunctions more easily. These improvements are expected to bring portable direct methanol fuel cells and stacks closer to commercialization. In a conventional bipolar fuel-cell stack, the cells are interspersed with bipolar plates (also called biplates), which are structural components that serve to interconnect the cells and distribute the reactants (methanol and air). The cells and biplates are sandwiched between metal end plates. Usually, the stack is held together under pressure by tie rods that clamp the end plates. The bipolar stack configuration offers the advantage of very low internal electrical resistance. However, when the power output of a stack is only a few watts, the very low internal resistance of a bipolar stack is not absolutely necessary for keeping the internal power loss acceptably low.

  20. Experimental study on the effect of volcanic residue on the performance of recycled lightweight aggregate concrete

    Science.gov (United States)

    Xiao, Li-guang; Li, Ji-heng; Liu, Qing-shun

    2017-08-01

    Recycled lightweight aggregate concrete prepared with waste brick recycled light aggregate has high water absorption, large apparent density and poor frost resistance. The technical measures of regen-erating lightweight aggregate concrete with modified waste bricks from volcanic slag are put forward. The effects of volcanic slag on the properties of waste lightweight aggregate concrete were studied. The experi-mental results show that volcanic slag can significantly reduce the apparent density of recycled lightweight aggregate concrete and improve its frost resistance.

  1. Three-legged platform in a plastic limit state

    Energy Technology Data Exchange (ETDEWEB)

    Lagoni, P

    1990-06-01

    This document provides structural description, formulars and a sample analysis of a platform supported by three piles and subject to loads that causes plastic deformation of the foundation (plastic limit state analysis). (au)

  2. Technological developments for ultra-lightweight, large aperture, deployable mirror for space telescopes

    Science.gov (United States)

    Zuccaro Marchi, Alessandro; D'Amato, Francesco; Gallieni, Daniele; Biasi, Roberto; Molina, Marco; Duò, Fabrizio; Ruder, Nikolaus; Salinari, Piero; Lisi, Franco; Riccardi, Armando; Gambicorti, Lisa; Simonetti, Francesca; Pereira do Carmo, Joao Pedro N.

    2017-11-01

    The increasing interest on space telescopes for scientific applications leads to implement the manufacturing technology of the most critical element, i.e. the primary mirror: being more suitable a large aperture, it must be lightweight and deployable. The presented topic was originally addressed to a spaceborne DIAL (Differential Absorption LIDAR) mission operating at 935.5 nm for the measurement of water vapour profile in atmosphere, whose results were presented at ICSO 2006 and 2008. Aim of this paper is to present the latest developments on the main issues related to the fabrication of a breadboard, covering two project critical areas identified during the preliminary studies: the design and performances of the long-stroke actuators used to implement the mirror active control and the mirror survivability to launch via Electrostatic Locking (EL) between mirror and backplane. The described work is developed under the ESA/ESTEC contract No. 22321/09/NL/RA. The lightweight mirror is structured as a central sector surrounded by petals, all of them actively controlled to reach the specified shape after initial deployment and then maintained within specs for the entire mission duration. The presented study concerns: a) testing the Carbon Fiber Reinforced Plastic (CFRP) backplane manufacturing and EL techniques, with production of suitable specimens; b) actuator design optimisation; c) design of the deployment mechanism including a high precision latch; d) the fabrication of thin mirrors mock-ups to validate the fabrication procedure for the large shells. The current activity aims to the construction of an optical breadboard capable of demonstrating the achievement of all these coupled critical aspects: optical quality of the thin shell mirror surface, actuators performances and back-plane - EL subsystem functionality.

  3. Transient Thermal Response of Lightweight Cementitious Composites Made with Polyurethane Foam Waste

    Science.gov (United States)

    Kismi, M.; Poullain, P.; Mounanga, P.

    2012-07-01

    The development of low-cost lightweight aggregate (LWA) mortars and concretes presents many advantages, especially in terms of lightness and thermal insulation performances of structures. Low-cost LWA mainly comes from the recovery of vegetal or plastic wastes. This article focuses on the characterization of the thermal conductivity of innovative lightweight cementitious composites made with fine particles of rigid polyurethane (PU) foam waste. Five mortars were prepared with various mass substitution rates of cement with PU-foam particles. Their thermal conductivity was measured with two transient methods: the heating-film method and the hot-disk method. The incorporation of PU-foam particles causes a reduction of up to 18 % of the mortar density, accompanied by a significant improvement of the thermal insulating performance. The effect of segregation on the thermal properties of LWA mortars due to the differences of density among the cementitious matrix, sand, and LWA has also been quantified. The application of the hot-disk method reveals a gradient of thermal conductivity along the thickness of the specimens, which could be explained by a non-uniform repartition of fine PU-foam particles and mineral aggregates within the mortars. The results show a spatial variation of the thermal conductivity of the LWA mortars, ranging from 9 % to 19 %. However, this variation remains close to or even lower than that observed on a normal weight aggregate mortar. Finally, a self-consistent approach is proposed to estimate the thermal conductivity of PU-foam cement-based composites.

  4. A lightweight portable, walk-in trap for catching vultures

    African Journals Online (AJOL)

    Two holes are drilled through the tubing and the piece of wood is attached to the tubing using 8.7 cm screws (Figure. 3). The location of the latch on the ... lightweight, walk-in trap, with door (shaded area) open, small black square shows location of gate latch. Figure 3. Close-up of gate latch. (photograph: David R. Barber).

  5. Design of Light-Weight High-Entropy Alloys

    Directory of Open Access Journals (Sweden)

    Rui Feng

    2016-09-01

    Full Text Available High-entropy alloys (HEAs are a new class of solid-solution alloys that have attracted worldwide attention for their outstanding properties. Owing to the demand from transportation and defense industries, light-weight HEAs have also garnered widespread interest from scientists for use as potential structural materials. Great efforts have been made to study the phase-formation rules of HEAs to accelerate and refine the discovery process. In this paper, many proposed solid-solution phase-formation rules are assessed, based on a series of known and newly-designed light-weight HEAs. The results indicate that these empirical rules work for most compositions but also fail for several alloys. Light-weight HEAs often involve the additions of Al and/or Ti in great amounts, resulting in large negative enthalpies for forming solid-solution phases and/or intermetallic compounds. Accordingly, these empirical rules need to be modified with the new experimental data. In contrast, CALPHAD (acronym of the calculation of phase diagrams method is demonstrated to be an effective approach to predict the phase formation in HEAs as a function of composition and temperature. Future perspectives on the design of light-weight HEAs are discussed in light of CALPHAD modeling and physical metallurgy principles.

  6. LETOS -- A Lightweight Execution Tool for Operational Semantics

    NARCIS (Netherlands)

    Hartel, Pieter H.

    A lightweight tool is proposed to aid in the development of operational semantics. To use LETOS an operational semantics must be expressed in its meta-language, which itself is a superset of Miranda. The LETOS compiler is smaller than comparable tools, yet LETOS is powerful enough to support

  7. Lightweight aluminum shock absorbers; Leichtbau-Stossdaempfer aus Aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Kusche, R. [Serienentwicklung, ThyssenKrupp Bilstein GmbH, Ennepetal (Germany)

    2004-12-01

    One way in which the automotive industry is striving to reduce costs and environmental impact is by continuously lowering the fuel consumption of vehicles. To achieve this objective, lightweight materials are increasingly being used in automotive design. Increasing demands are also being made on shock absorber suppliers to reduce weight. (orig.)

  8. Developments in Emission Measurements Using Lightweight Sensors and Samplers.

    Science.gov (United States)

    Lightweight emission measurement systems making use of miniaturized sensors and samplers have been developed for portable and aerial sampling for an array of pollutants. Shoebox-sized systems called “Kolibri”, weighing 3-5 kg, have been deployed on NASA-flown unmanned...

  9. Performance of Lightweight Natural-Fiber Reinforced Concrete

    Directory of Open Access Journals (Sweden)

    Hardjasaputra Harianto

    2017-01-01

    Full Text Available Concrete, the most common construction material, has negligible tension capacity. However, a reinforcement material such as natural fibers, can be used to improve the tensile properties of concrete. This paper presents experiments conducted on Super Lightweight Concrete mixed with coconut fibers (SLNFRC. Coconut fibers are regarded as one of the toughest natural fibers to strengthen concrete. Coconut fiber reinforced composites have been considered as a sustainable construction material because the fibers are derived from waste. These wastes, which are available in large quantities in Asia, have to be extracted from the husk of coconut fruits and must pass a mechanical process before being added to a concrete mixture. The Super Lightweight Concrete was made by mixing concrete paste with foam agent that can reduce the overall weight of concrete up to 60% with compressive strength up to 6 MPa. The Super Lightweight Concrete is intended to be used for non-structural walls, as alternative conventional construction materials such as brick walls. The influence of coconut fibers content in increasing the flexural tensile strength of Super Lightweight Concrete was studied in this research. The fiber content studied include 0%, 0.1%, 0.175%, and 0.25% by weight of cement content. Sixteen specimens of SLNFRC mini beams of 60 mm x 60 mm x 300 mm were tested to failure to investigate their flexural strengths. The optimum percent fibers yielding higher tensile strength was found to be 0.175%

  10. data sets Simulations in articulating light-weight PRS

    NARCIS (Netherlands)

    Van den Berg, Bert

    2008-01-01

    The data sets are output of 3 different steps in the development a simulations of a PRS as described in chapter 3.3: Simulations in articulating light-weight PRS A case for Pedagogy-oriented and Rating-based Hybrid Recommendation Strategies Rob Nadolski, Bert van den Berg, Adriana Berlanga, Hans

  11. Influence of site curing on bond properties of reinforced lightweight ...

    African Journals Online (AJOL)

    ... the requirements for structural lightweight concrete. The developed compressive strength and pull-out strength under both site curing conditions were relatively lower than full water curing condition but still were higher than minimum requirement as per standard. Journal of Civil Engineering Research and Practice Vol.

  12. Reducing CO2 Emissions through Lightweight Design and Manufacturing

    Science.gov (United States)

    Carruth, Mark A.; Allwood, Julian M.; Milford, Rachel L.

    2011-05-01

    To meet targeted 50% reductions in industrial CO2 emissions by 2050, demand for steel and aluminium must be cut. Many steel and aluminium products include redundant material, and the manufacturing routes to produce them use more material than is necessary. Lightweight design and optimized manufacturing processes offer a means of demand reduction, whilst creating products to perform the same service as existing ones. This paper examines two strategies for demand reduction: lightweight product design; and minimizing yield losses through the product supply chain. Possible mass savings are estimated for specific case-studies on metal-intensive products, such as I-beams and food cans. These estimates are then extrapolated to other sectors to produce a global estimate for possible demand reductions. Results show that lightweight product design may offer potential mass savings of up to 30% for some products, whilst yield in the production of others could be improved by over 20%. If these two strategies could be combined for all products, global demand for steel and aluminium would be reduced by nearly 50%. The impact of demand reduction on CO2 emissions is presented, and barriers to the adoption of new, lightweight technologies are discussed.

  13. Robustness of Modal Parameter Estimation Methods Applied to Lightweight Structures

    DEFF Research Database (Denmark)

    Dickow, Kristoffer Ahrens; Kirkegaard, Poul Henning; Andersen, Lars Vabbersgaard

    2013-01-01

    On-going research is concerned with the losses that occur at junctions in lightweight building structures. Recently the authors have investigated the underlying uncertainties related to both measurement, material and craftsmanship of timber junctions by means of repeated modal testing on a number...

  14. Accuracy of Dynamic and Acoustic Analysis of Lightweight Panel Structures

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Dickow, Kristoffer Ahrens; Andersen, Lars Vabbersgaard

    2012-01-01

    in such buildings is important. In the lowfrequency range, prediction of sound and vibration in building structures may be achieved by finite-element analysis (FEA). The aim of this paper is to compare the two commercial codes ABAQUS and ANSYS for FEA of an acoustic-structural coupling in a timber lightweight panel...

  15. Study of the strength characteristics of protein-based lightweight ...

    African Journals Online (AJOL)

    Compressive strength test was carried out on the protein-based lightweight foamed concrete produced with cement partially replaced by rice husk ash to ascertain its strength characteristics. Standard concrete cubes of 150 x 150 x 150 mm were produced using ordinary Portland cement (OPC), fine aggregate, aqueous ...

  16. APE: Authenticated Permutation-Based Encryption for Lightweight Cryptography

    DEFF Research Database (Denmark)

    Andreeva, Elena; Bilgin, Begül; Bogdanov, Andrey

    2015-01-01

    The domain of lightweight cryptography focuses on cryptographic algorithms for extremely constrained devices. It is very costly to avoid nonce reuse in such environments, because this requires either a hardware source of randomness, or non-volatile memory to store a counter. At the same time, a lot...

  17. Metal-bending brake facilitates lightweight, close-tolerance fabrication

    Science.gov (United States)

    Ercoline, A. L.; Wilton, K. B.

    1964-01-01

    A lightweight, metal bending brake ensures very accurate bends. Features of the brake that adapt it for making complex reverse bends to close tolerances are a pronounced relief or cutaway of the underside of the bodyplate combined with modification in the leaf design and its suspension.

  18. STRENGTH OF NANOMODIFIED HIGH-STRENGTH LIGHTWEIGHT CONCRETES

    Directory of Open Access Journals (Sweden)

    NOZEMTСEV Alexandr Sergeevich

    2013-02-01

    Full Text Available The paper presents the results of research aimed at development of nanomodified high-strength lightweight concrete for construction. The developed concretes are of low average density and high ultimate compressive strength. It is shown that to produce this type of concrete one need to use hollow glass and aluminosilicate microspheres. To increase the durability of adhesion between cement stone and fine filler the authors offer to use complex nanodimensinal modifier based on iron hydroxide sol and silica sol as a surface nanomodifier for hollow microspheres. It is hypothesized that the proposed modifier has complex effect on the activity of the cement hydration and, at the same time increases bond strength between filler and cement-mineral matrix. The compositions for energy-efficient nanomodified high-strength lightweight concrete which density is 1300…1500 kg/m³ and compressive strength is 40…65 MPa have been developed. The approaches to the design of high-strength lightweight concrete with density of less than 2000 kg/m³ are formulated. It is noted that the proposed concretes possess dense homogeneous structure and moderate mobility. Thus, they allow processing by vibration during production. The economic and practical implications for realization of high-strength lightweight concrete in industrial production have been justified.

  19. Lightweighting Impacts on Fuel Economy, Cost, and Component Losses

    Energy Technology Data Exchange (ETDEWEB)

    Brooker, A. D.; Ward, J.; Wang, L.

    2013-01-01

    The Future Automotive Systems Technology Simulator (FASTSim) is the U.S. Department of Energy's high-level vehicle powertrain model developed at the National Renewable Energy Laboratory. It uses a time versus speed drive cycle to estimate the powertrain forces required to meet the cycle. It simulates the major vehicle powertrain components and their losses. It includes a cost model based on component sizing and fuel prices. FASTSim simulated different levels of lightweighting for four different powertrains: a conventional gasoline engine vehicle, a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), and a battery electric vehicle (EV). Weight reductions impacted the conventional vehicle's efficiency more than the HEV, PHEV and EV. Although lightweighting impacted the advanced vehicles' efficiency less, it reduced component cost and overall costs more. The PHEV and EV are less cost effective than the conventional vehicle and HEV using current battery costs. Assuming the DOE's battery cost target of $100/kWh, however, the PHEV attained similar cost and lightweighting benefits. Generally, lightweighting was cost effective when it costs less than $6/kg of mass eliminated.

  20. FY2013 Lightweight Materials R&D Annual Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2014-02-01

    As part of the U.S. Department of Energy’s (DOE’s) Vehicle Technologies Program (VTO), the Lightweight Materials (LM) activity focuses on the development and validation of advanced materials and manufacturing technologies to significantly reduce light and heavy duty vehicle weight without compromising other attributes such as safety, performance, recyclability, and cost.

  1. Closing the innovation cycle in lightweighting compressor pistons technolog

    NARCIS (Netherlands)

    Wentzel, C.; Eijk, A.; Groenewegen, G.; Bergsma, O.

    2016-01-01

    What started out as an exercise in exploring the weight reduction potential of those allegedly “heavy recip crossheads”, turned out to be a fast leap towards implementation of a new hybrid material concept for very lightweight pistons. This was enabled by a next phase in the EFRC R&D group research

  2. Closing the innovation cycle in lightweighting compressor pistons technology

    NARCIS (Netherlands)

    Wentzel, C.M.; Eijk, A.; Groenewegen, G.; Bergsma, O.K.

    2016-01-01

    What started out as an exercise in exploring the weight reduction potential of those allegedly “heavy recip crossheads”, turned out to be a fast leap towards implementation of a new hybrid material concept for very lightweight pistons. This was enabled by a next phase in the EFRC R&D group

  3. FY2010 Annual Progress Report for Lightweighting Materials

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2011-01-15

    The Lightweight Materials activity (LM) within the Vehicle Technologies Program focuses on the development and validation of advanced materials and manufacturing technologies to significantly reduce light and heavy duty vehicle weight without compromising other attributes such as safety, performance, recyclability, and cost.

  4. Development of lightweight mortars targeted on the high strength, low density and low permeability

    NARCIS (Netherlands)

    Spiesz, P.R.; Yu, Q.; Brouwers, H.J.H.; Uzoegbo, H.C.; Schmidt, W.

    2013-01-01

    This article presents a mix design methodology for the development of cement-based lightweight mortars. Expanded-glass lightweight aggregates were used in this study as the lightweight material. The mix design was developed applying the packing theory using the modified Andreasen and Andersen model

  5. Lightweight panel study 2012: Perceptions and usage by North American wood products manufacturers

    Science.gov (United States)

    Urs Buehlmann; Matt Bumgardner; Karl D. Forth

    2012-01-01

    Lightweight panels (panels made of two thin panels on the outside and a lightweight material in the core) can offer enhanced performance, reduced material use, and new design opportunities over traditional types of panels. Opportunities exist for the adoption of lightweight panels by the secondary wood industry in North America, as 62 percent of respondents to a recent...

  6. From macro- to microplastics - Analysis of EU regulation along the life cycle of plastic bags.

    Science.gov (United States)

    Steensgaard, Ida M; Syberg, Kristian; Rist, Sinja; Hartmann, Nanna B; Boldrin, Alessio; Hansen, Steffen Foss

    2017-05-01

    Plastic pollution and its environmental effects has received global attention the recent years. However, limited attention has so far been directed towards how plastics are regulated in a life cycle perspective and how regulatory gaps can be addressed in order to limit and prevent environmental exposure and hazards of macro- and microplastics. In this paper, we map European regulation taking outset in the life cycle perspective of plastic carrier bags: from plastic bag production to when it enters the environment. Relevant regulatory frameworks, directives and authorities along the life cycle are identified and their role in regulation of plastics is discussed. Most important regulations were identified as: the EU chemical Regulation, the Packaging and Packaging Waste Directive including the amending Directive regarding regulation of the consumption of lightweight plastic carrier bags, the Waste Framework Directive and the Directive on the Landfill of Waste. The main gaps identified relate to lack of clear definitions of categories of polymers, unambitious recycling rates and lack of consideration of macro- and microplastics in key pieces of legislation. We recommend that polymers are categorized according to whether they are polymers with the same monomer constituents (homopolymers) or with different monomer constituents (copolymers) and that polymers are no longer exempt from registration and evaluation under REACH. Plastics should furthermore have the same high level of monitoring and reporting requirements as hazardous waste involving stricter requirements to labelling, recordkeeping, monitoring and control over the whole lifecycle. Finally, we recommend that more ambitious recycle and recovery targets are set across the EU. Regulation of the consumption of lightweight plastic carrier bags should also apply to heavyweight plastic carrier bags. Last, the Marine and Water Framework Directives should specifically address plastic waste affecting water quality

  7. Avalanches and plastic flow in crystal plasticity: an overview

    Science.gov (United States)

    Papanikolaou, Stefanos; Cui, Yinan; Ghoniem, Nasr

    2018-01-01

    Crystal plasticity is mediated through dislocations, which form knotted configurations in a complex energy landscape. Once they disentangle and move, they may also be impeded by permanent obstacles with finite energy barriers or frustrating long-range interactions. The outcome of such complexity is the emergence of dislocation avalanches as the basic mechanism of plastic flow in solids at the nanoscale. While the deformation behavior of bulk materials appears smooth, a predictive model should clearly be based upon the character of these dislocation avalanches and their associated strain bursts. We provide here a comprehensive overview of experimental observations, theoretical models and computational approaches that have been developed to unravel the multiple aspects of dislocation avalanche physics and the phenomena leading to strain bursts in crystal plasticity.

  8. Avian Feathers: An Examination of Lightweight Resilience and Bioinspired Designs

    Science.gov (United States)

    Sullivan, Tarah Naoe

    In bird flight, the majority of the wing surface consists of highly refined and hierarchically organized beta-keratinous feathers. Thus, flight feathers contain ingenious combinations of components that optimize lift, stiffness, aerodynamics, and damage resistance. Their design involves two main parts: a central shaft which prescribes stiffness and lateral vanes that allow for the capture of air. Within the feather vane, barbs branch from the shaft and barbules branch from barbs, forming a flat surface and ensuring lift. Microhooks at the end of barbules hold barbs tightly together, providing a close-knit, unified structure and enabling repair of the vane through the reattachment of un-hooked junctions. In this dissertation, unique aspects of feather architecture are explored to uncover principles translatable to the design of modern aerospace materials and structures. Specifically, understudied aspects of the feather's lightweight yet resilient properties are investigated. This research has revealed several novel characteristics of the feather. Allometric scaling relationships are developed linking the geometry of a bird's wing components to its flight characteristics and total mass. Barbule spacing within the feather vane is found to be 8-16 microm for birds ranging from 0.02-11 kg. Additionally, it is discovered that strength is recovered with the shape recovery property of feathers, and a mechanism for this phenomenon is proposed. Barbule adhesion within the vane is found to prevent barbs from twisting in flexure, maintaining the vane's stiffness, and the extent to which unzipping these connections affects the feather's ability to capture air is related to barb shape. Directional permeability of the feather vane is experimentally confirmed and related to the intricate microstructure of barbules. Lastly, the exceptional architecture of the feather motivated the design of novel bioinspired structures with tailored and unique properties. The avian feather serves

  9. Development of in-situ radon sensor using plastic scintillator

    International Nuclear Information System (INIS)

    Shitashima, Kiminori

    2009-01-01

    Underwater in-situ radon measurement is important scientific priority for oceanography, especially for survey and monitoring of submarine groundwater discharge (SDG). The high sensitivity and lightweight underwater in-situ radon sensor using NaI(Tl) doped plastic scintillator was developed for application to SDG research. Because NaI(Tl) doped plastic scintillator contacts seawater directly, the plastic scintillator can expect high sensitivity in comparison with NaI(Tl) crystal sealed in a container. In order to improve condensation efficiency of scintillation, the plastic scintillator was processed in funnel form and coated by light-resistant paint. This sensor consists of plastic scintillator, photomultiplier tube, preamplifier unit, high-voltage power supply, data logger and lithium-ion battery, and all parts are stored in a pressure housing (200φx300L). The newly developed underwater in-situ radon sensor was tested at hydrothermal area (underwater hot springs) that the hydrothermal fluid containing high concentration of radon is discharged into seawater. The sensor was operated by a diver, and sensitivity tests and mapping survey for estimation of radon diffusion were carried out. The signals of the radon sensor ranged from 20 to 65 mV, and these signals corresponded with radon concentration of 2 to 12 becquerels per liter. The sensor was able to detect radon to 20 m above the hydrothermal point (seafloor). Since the sensor is small and light-weight, measurement, monitoring and mapping can perform automatically by installing the sensor to an AUV (autonomous underwater vehicle). Furthermore, underwater in-situ radon sensor is expected an application to earthquake prediction and volcanic activity monitoring as well as oceanography and hydrology. (author)

  10. Bibliometric trend analyses of plastic surgery research

    NARCIS (Netherlands)

    Loonen, M.P.J.

    2007-01-01

    The present thesis was designed to evaluate the qualitative and quantitative aspects of plastic surgery research by means of a bibliometric citation analysis of plastic surgical presentations and publications. Citations to such published work provides an indication of the impact and the relevance of

  11. TIDE: Lightweight Device Composition for Enhancing Tabletop Environments with Smartphone Applications

    DEFF Research Database (Denmark)

    Sicard, Leo; Tabard, Aurelien; Ramos, Juan David Hincapie

    2013-01-01

    platforms have to be re-developed. At the same time, smartphones are pervasive computers that users carry around and with a large pool of applications. This paper presents TIDE, a lightweight device composition middleware to bring existing smartphone applica- tions onto the tabletop. Through TIDE......, applications running on the smartphone are displayed on the tabletop computer, and users can interact with them through the tabletop’s interactive surface. TIDE contributes to the areas of device compo- sition and tabletops by providing an OS-level middleware that is transparent to the smartphone applications...

  12. Effects of Wastes from the Brewing Industry in Lightweight Aggregates Manufactured with Clay for Green Roofs

    Science.gov (United States)

    Farías, Romina D.; Martínez García, Carmen; Cotes Palomino, Teresa; Martínez Arellano, Myriam

    2017-01-01

    This study investigates the effects of sieved wastes generated from the brewing industry on lightweight aggregates manufactured with clay. Sludge from a wastewater treatment plant, bagasse and diatomaceous earth were used to obtain the samples. These wastes are usually dumped in landfills, but the current increase in restrictions on dumping and interest in improving the environment make our proposal for gaining value from these wastes a significant contribution. Laboratory tests show that the new aggregate has low bulk density and increased water absorption and porosity. The thermographic camera results provide evidence that new aggregates have significant insulating properties and are suitable for use on green roofs. PMID:28772892

  13. Developments in the synthesis, processing and applications of light-weight metallic materials

    International Nuclear Information System (INIS)

    Mazhar, A.A.; Froes, F.H.; Trindade, B.

    2003-01-01

    The low-density metallic materials aluminium, magnesium and titanium are important in many segments of the world economy, ranging from aerospace to sports equipment. The importance of cost is strongly dependant on the industry being considered: in the construction and automobile industries, cost is extremely important, while in the aerospace and medical industries, performance is emphasized over cost. The paper provides an overview of the synthesis, processing, microstructures, mechanical properties and applications of these lightweight materials and discusses the importance of cost-effective processing. (author)

  14. Effects of Wastes from the Brewing Industry in Lightweight Aggregates Manufactured with Clay for Green Roofs

    Directory of Open Access Journals (Sweden)

    Romina D. Farías

    2017-05-01

    Full Text Available This study investigates the effects of sieved wastes generated from the brewing industry on lightweight aggregates manufactured with clay. Sludge from a wastewater treatment plant, bagasse and diatomaceous earth were used to obtain the samples. These wastes are usually dumped in landfills, but the current increase in restrictions on dumping and interest in improving the environment make our proposal for gaining value from these wastes a significant contribution. Laboratory tests show that the new aggregate has low bulk density and increased water absorption and porosity. The thermographic camera results provide evidence that new aggregates have significant insulating properties and are suitable for use on green roofs.

  15. Medium-scale carbon nanotube thin-film integrated circuits on flexible plastic substrates.

    Science.gov (United States)

    Cao, Qing; Kim, Hoon-sik; Pimparkar, Ninad; Kulkarni, Jaydeep P; Wang, Congjun; Shim, Moonsub; Roy, Kaushik; Alam, Muhammad A; Rogers, John A

    2008-07-24

    The ability to form integrated circuits on flexible sheets of plastic enables attributes (for example conformal and flexible formats and lightweight and shock resistant construction) in electronic devices that are difficult or impossible to achieve with technologies that use semiconductor wafers or glass plates as substrates. Organic small-molecule and polymer-based materials represent the most widely explored types of semiconductors for such flexible circuitry. Although these materials and those that use films or nanostructures of inorganics have promise for certain applications, existing demonstrations of them in circuits on plastic indicate modest performance characteristics that might restrict the application possibilities. Here we report implementations of a comparatively high-performance carbon-based semiconductor consisting of sub-monolayer, random networks of single-walled carbon nanotubes to yield small- to medium-scale integrated digital circuits, composed of up to nearly 100 transistors on plastic substrates. Transistors in these integrated circuits have excellent properties: mobilities as high as 80 cm(2) V(-1) s(-1), subthreshold slopes as low as 140 m V dec(-1), operating voltages less than 5 V together with deterministic control over the threshold voltages, on/off ratios as high as 10(5), switching speeds in the kilohertz range even for coarse (approximately 100-microm) device geometries, and good mechanical flexibility-all with levels of uniformity and reproducibility that enable high-yield fabrication of integrated circuits. Theoretical calculations, in contexts ranging from heterogeneous percolative transport through the networks to compact models for the transistors to circuit level simulations, provide quantitative and predictive understanding of these systems. Taken together, these results suggest that sub-monolayer films of single-walled carbon nanotubes are attractive materials for flexible integrated circuits, with many potential areas of

  16. Plastic value chains

    DEFF Research Database (Denmark)

    Baxter, John; Wahlstrom, Margareta; Zu Castell-Rüdenhausen, Malin

    2014-01-01

    Optimizing plastic value chains is regarded as an important measure in order to increase recycling of plastics in an efficient way. This can also lead to improved awareness of the hazardous substances contained in plastic waste, and how to avoid that these substances are recycled. As an example......, plastics from WEEE is chosen as a Nordic case study. The project aims to propose a number of improvements for this value chain together with representatives from Nordic stakeholders. Based on the experiences made, a guide for other plastic value chains shall be developed....

  17. Biodegradability of Plastics

    Directory of Open Access Journals (Sweden)

    Yutaka Tokiwa

    2009-08-01

    Full Text Available Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical properties (melting point, glass transition temperature, crystallinity, storage modulus etc.. In this review, microbial and enzymatic biodegradation of plastics and some factors that affect their biodegradability are discussed.

  18. Biodegradability of plastics.

    Science.gov (United States)

    Tokiwa, Yutaka; Calabia, Buenaventurada P; Ugwu, Charles U; Aiba, Seiichi

    2009-08-26

    Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical properties (melting point, glass transition temperature, crystallinity, storage modulus etc.). In this review, microbial and enzymatic biodegradation of plastics and some factors that affect their biodegradability are discussed.

  19. Plastic solidification of radioactive wastes

    International Nuclear Information System (INIS)

    Moriyama, Noboru

    1981-01-01

    Over 20 years have elapsed after the start of nuclear power development, and the nuclear power generation in Japan now exceeds the level of 10,000 MW. In order to meet the energy demands, the problem of the treatment and disposal of radioactive wastes produced in nuclear power stations must be solved. The purpose of the plastic solidification of such wastes is to immobilize the contained radionuclides, same as other solidification methods, to provide the first barrier against their move into the environment. The following matters are described: the nuclear power generation in Japan, the radioactive wastes from LWR plants, the position of plastic solidification, the status of plastic solidification in overseas countries and in Japan, the solidification process for radioactive wastes with polyethylene, and the properties of solidified products, and the leachability of radionuclides in asphalt solids. (J.P.N.)

  20. Challenges in plastics recycling

    DEFF Research Database (Denmark)

    Pivnenko, Kostyantyn; Jakobsen, L. G.; Eriksen, Marie Kampmann

    2015-01-01

    Recycling of waste plastics still remains a challenging area in the waste management sector. The current and potential goals proposed on EU or regional levels are difficult to achieve, and even to partially fullfil them the improvements in collection and sorting should be considerable. A study...... was undertaken to investigate the factors affecting quality in plastics recycling. The preliminary results showed factors primarily influencing quality of plastics recycling to be polymer cross contamination, presence of additives, non-polymer impurities, and polymer degradation. Deprivation of plastics quality......, with respect to recycling, has been shown to happen throughout the plastics value chain, but steps where improvements may happen have been preliminary identified. Example of Cr in plastic samples analysed showed potential spreading and accumulation of chemicals ending up in the waste plastics. In order...

  1. An investigation on the use of shredded waste PET bottles as aggregate in lightweight concrete

    International Nuclear Information System (INIS)

    Akcaoezoglu, Semiha; Atis, Cengiz Duran; Akcaoezoglu, Kubilay

    2010-01-01

    In this work, the utilization of shredded waste Poly-ethylene Terephthalate (PET) bottle granules as a lightweight aggregate in mortar was investigated. Investigation was carried out on two groups of mortar samples, one made with only PET aggregates and, second made with PET and sand aggregates together. Additionally, blast-furnace slag was also used as the replacement of cement on mass basis at the replacement ratio of 50% to reduce the amount of cement used and provide savings. The water-binder (w/b) ratio and PET-binder (PET/b) ratio used in the mixtures were 0.45 and 0.50, respectively. The size of shredded PET granules used in the preparation of mortar mixtures were between 0 and 4 mm. The results of the laboratory study and testing carried out showed that mortar containing only PET aggregate, mortar containing PET and sand aggregate, and mortars modified with slag as cement replacement can be drop into structural lightweight concrete category in terms of unit weight and strength properties. Therefore, it was concluded that there is a potential for the use of shredded waste PET granules as aggregate in the production of structural lightweight concrete. The use of shredded waste PET granules due to its low unit weight reduces the unit weight of concrete which results in a reduction in the death weight of a structural concrete member of a building. Reduction in the death weight of a building will help to reduce the seismic risk of the building since the earthquake forces linearly dependant on the dead-weight. Furthermore, it was also concluded that the use of industrial wastes such as PET granules and blast-furnace slag in concrete provides some advantages, i.e., reduction in the use of natural resources, disposal of wastes, prevention of environmental pollution, and energy saving.

  2. An investigation on the use of shredded waste PET bottles as aggregate in lightweight concrete.

    Science.gov (United States)

    Akçaözoğlu, Semiha; Atiş, Cengiz Duran; Akçaözoğlu, Kubilay

    2010-02-01

    In this work, the utilization of shredded waste Poly-ethylene Terephthalate (PET) bottle granules as a lightweight aggregate in mortar was investigated. Investigation was carried out on two groups of mortar samples, one made with only PET aggregates and, second made with PET and sand aggregates together. Additionally, blast-furnace slag was also used as the replacement of cement on mass basis at the replacement ratio of 50% to reduce the amount of cement used and provide savings. The water-binder (w/b) ratio and PET-binder (PET/b) ratio used in the mixtures were 0.45 and 0.50, respectively. The size of shredded PET granules used in the preparation of mortar mixtures were between 0 and 4 mm. The results of the laboratory study and testing carried out showed that mortar containing only PET aggregate, mortar containing PET and sand aggregate, and mortars modified with slag as cement replacement can be drop into structural lightweight concrete category in terms of unit weight and strength properties. Therefore, it was concluded that there is a potential for the use of shredded waste PET granules as aggregate in the production of structural lightweight concrete. The use of shredded waste PET granules due to its low unit weight reduces the unit weight of concrete which results in a reduction in the death weight of a structural concrete member of a building. Reduction in the death weight of a building will help to reduce the seismic risk of the building since the earthquake forces linearly dependent on the dead-weight. Furthermore, it was also concluded that the use of industrial wastes such as PET granules and blast-furnace slag in concrete provides some advantages, i.e., reduction in the use of natural resources, disposal of wastes, prevention of environmental pollution, and energy saving.

  3. Cold surface treatments on fiber-reinforced plastics by pulsed laser

    OpenAIRE

    Gebauer, Jana; Franke, Volker; Klotzbach, Udo; Beyer, Eckhard

    2017-01-01

    The importance of lightweight materials increases in all aspects of manufacturing, e.g. automotive, sports equipment and aerospace [1]. Making fiber reinforced plastics suitable for use in mass production new technologies have to be developed to overcome existing challenges e.g. shorter cycle times or more efficient resource usage. Innovative laser systems are used for a full range of treatments for all materials, like structuring, drilling, joining and cutting [2] - [4]. This paper presents ...

  4. Process combinations for the manufacturing of metal-plastic hybrid parts

    OpenAIRE

    Drossel, Welf-Guntram; Lies, Carsten; Albert, André; Haase, Rico; Müller, Roland; Scholz, Peter

    2016-01-01

    The usage of innovative lightweight materials and processing technologies gains importance in manifold industrial scopes. Especially for moving parts and mobility products the weight is decisively. The aerospace and automotive industries use light and high-strength materials to reduce weight and energy consumption and thereby improve the performance of their products. Composites with reinforced plastics are of particular importance. They offer a low density in combination with high specific s...

  5. Precise Alignment and Permanent Mounting of Thin and Lightweight X-ray Segments

    Science.gov (United States)

    Biskach, Michael P.; Chan, Kai-Wing; Hong, Melinda N.; Mazzarella, James R.; McClelland, Ryan S.; Norman, Michael J.; Saha, Timo T.; Zhang, William W.

    2012-01-01

    To provide observations to support current research efforts in high energy astrophysics. future X-ray telescope designs must provide matching or better angular resolution while significantly increasing the total collecting area. In such a design the permanent mounting of thin and lightweight segments is critical to the overall performance of the complete X-ray optic assembly. The thin and lightweight segments used in the assemhly of the modules are desigued to maintain and/or exceed the resolution of existing X-ray telescopes while providing a substantial increase in collecting area. Such thin and delicate X-ray segments are easily distorted and yet must be aligned to the arcsecond level and retain accurate alignment for many years. The Next Generation X-ray Optic (NGXO) group at NASA Goddard Space Flight Center has designed, assembled. and implemented new hardware and procedures mth the short term goal of aligning three pairs of X-ray segments in a technology demonstration module while maintaining 10 arcsec alignment through environmental testing as part of the eventual design and construction of a full sized module capable of housing hundreds of X-ray segments. The recent attempts at multiple segment pair alignment and permanent mounting is described along with an overview of the procedure used. A look into what the next year mll bring for the alignment and permanent segment mounting effort illustrates some of the challenges left to overcome before an attempt to populate a full sized module can begin.

  6. Use of recycled plastics in concrete: A critical review.

    Science.gov (United States)

    Gu, Lei; Ozbakkaloglu, Togay

    2016-05-01

    Plastics have become an essential part of our modern lifestyle, and the global plastic production has increased immensely during the past 50years. This has contributed greatly to the production of plastic-related waste. Reuse of waste and recycled plastic materials in concrete mix as an environmental friendly construction material has drawn attention of researchers in recent times, and a large number of studies reporting the behavior of concrete containing waste and recycled plastic materials have been published. This paper summarizes the current published literature until 2015, discussing the material properties and recycling methods of plastic and the influence of plastic materials on the properties of concrete. To provide a comprehensive review, a total of 84 studies were considered, and they were classified into sub categories based on whether they dealt with concrete containing plastic aggregates or plastic fibers. Furthermore, the morphology of concrete containing plastic materials is described in this paper to explain the influence of plastic aggregates and plastic fibers on the properties of concrete. The properties of concretes containing virgin plastic materials were also reviewed to establish their similarities and differences with concrete containing recycled plastics. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Liquid crystal displays with plastic substrates

    Science.gov (United States)

    Lueder, Ernst H.

    1998-04-01

    Plastic substrates for the cells of displays exhibit only 1/6 of the weight of glass substrates; they are virtually unbreakable; their flexibility allows the designer to give them a shape suppressing reflections, to realize a display board on a curved surface or meeting the requirements for an appealing styling; displays with plastics are thinner which provides a wider viewing angle. These features render them attractive for displays in portable systems such as mobile phones, pagers, smart cards, personal digital assistants (PDAs) and portable computers. Reflective displays are especially attractive as they don't need a back light. The most important requirements are the protection of plastics against gas permeation and chemical agents, the prevention of layers on plastics to crack or peel off when the plastic is bent and the development of low temperature thin film processes because the plastics, as a rule, only tolerate temperatures below 150 degrees Celsius. Bistable reflective FLC- and PSCT-displays with plastic substrates will be introduced. Special sputtered SiO2-orientation layers preserve the displayed information even if pressure or torsion is applied. MIM-addressed PDLC-displays require additional Al- or Ti-layers which provide the necessary ductility. Sputtered or PECVD-generated TFTs can be fabricated on plastics at temperatures below 150 degrees Celsius.

  8. 49 CFR 192.123 - Design limitations for plastic pipe.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Design limitations for plastic pipe. 192.123... Design limitations for plastic pipe. (a) Except as provided in paragraph (e) and paragraph (f) of this section, the design pressure may not exceed a gauge pressure of 100 psig (689 kPa) for plastic pipe used...

  9. Fiber breakage phenomena in long fiber reinforced plastic preparation

    International Nuclear Information System (INIS)

    Huang, Chao-Tsai; Tseng, Huan-Chang; Chang, Rong-Yeu; Vlcek, Jiri

    2015-01-01

    Due to the high demand of smart green, the lightweight technologies have become the driving force for the development of automotives and other industries in recent years. Among those technologies, using short and long fiber-reinforced plastics (FRP) to replace some metal components can reduce the weight of an automotive significantly. However, the microstructures of fibers inside plastic matrix are too complicated to manage and control during the injection molding through the screw, the runner, the gate, and then into the cavity. This study focuses on the fiber breakage phenomena during the screw plastification. Results show that fiber breakage is strongly dependent on screw design and operation. When the screw geometry changes, the fiber breakage could be larger even with lower compression ratio. (paper)

  10. Our plastic age.

    Science.gov (United States)

    Thompson, Richard C; Swan, Shanna H; Moore, Charles J; vom Saal, Frederick S

    2009-07-27

    Within the last few decades, plastics have revolutionized our daily lives. Globally we use in excess of 260 million tonnes of plastic per annum, accounting for approximately 8 per cent of world oil production. In this Theme Issue of Philosophical Transactions of the Royal Society, we describe current and future trends in usage, together with the many benefits that plastics bring to society. At the same time, we examine the environmental consequences resulting from the accumulation of waste plastic, the effects of plastic debris on wildlife and concerns for human health that arise from the production, usage and disposal of plastics. Finally, we consider some possible solutions to these problems together with the research and policy priorities necessary for their implementation.

  11. Our plastic age

    Science.gov (United States)

    Thompson, Richard C.; Swan, Shanna H.; Moore, Charles J.; vom Saal, Frederick S.

    2009-01-01

    Within the last few decades, plastics have revolutionized our daily lives. Globally we use in excess of 260 million tonnes of plastic per annum, accounting for approximately 8 per cent of world oil production. In this Theme Issue of Philosophical Transactions of the Royal Society, we describe current and future trends in usage, together with the many benefits that plastics bring to society. At the same time, we examine the environmental consequences resulting from the accumulation of waste plastic, the effects of plastic debris on wildlife and concerns for human health that arise from the production, usage and disposal of plastics. Finally, we consider some possible solutions to these problems together with the research and policy priorities necessary for their implementation. PMID:19528049

  12. Adaptive Backstepping Control of Lightweight Tower Wind Turbine

    DEFF Research Database (Denmark)

    Galeazzi, Roberto; Borup, Kasper Trolle; Niemann, Hans Henrik

    2015-01-01

    the angular deflection of the tower with respect to the vertical axis in response to variations in wind speed. The controller is shown to guarantee asymptotic tracking of the reference trajectory. The performance of the control system is evaluated through deterministic and stochastic simulations including......This paper investigates the feasibility of operating a wind turbine with lightweight tower in the full load region exploiting an adaptive nonlinear controller that allows the turbine to dynamically lean against the wind while maintaining nominal power output. The use of lightweight structures...... for towers and foundations would greatly reduce the construction cost of the wind turbine, however extra features ought be included in the control system architecture to avoid tower collapse. An adaptive backstepping collective pitch controller is proposed for tower point tracking control, i.e. to modify...

  13. Hot stamping advanced manufacturing technology of lightweight car body

    CERN Document Server

    Hu, Ping; He, Bin

    2017-01-01

    This book summarizes the advanced manufacturing technology of original innovations in hot stamping of lightweight car body. A detailed description of the technical system and basic knowledge of sheet metal forming is given, which helps readers quickly understand the relevant knowledge in the field. Emphasis has been placed on the independently developed hot stamping process and equipment, which help describe the theoretical and experimental research on key problems involving stress field, thermal field and phase transformation field in hot stamping process. Also, a description of the formability at elevated temperature and the numerical simulation algorithms for high strength steel hot stamping is given in combination with the experiments. Finally, the book presents some application cases of hot stamping technology such as the lightweight car body design using hot stamping components and gradient hardness components, and the cooling design of the stamping tool. This book is intended for researchers, engineers...

  14. Computational imaging using lightweight diffractive-refractive optics

    KAUST Repository

    Peng, Yifan

    2015-11-23

    Diffractive optical elements (DOE) show great promise for imaging optics that are thinner and more lightweight than conventional refractive lenses while preserving their light efficiency. Unfortunately, severe spectral dispersion currently limits the use of DOEs in consumer-level lens design. In this article, we jointly design lightweight diffractive-refractive optics and post-processing algorithms to enable imaging under white light illumination. Using the Fresnel lens as a general platform, we show three phase-plate designs, including a super-thin stacked plate design, a diffractive-refractive-hybrid lens, and a phase coded-aperture lens. Combined with cross-channel deconvolution algorithm, both spherical and chromatic aberrations are corrected. Experimental results indicate that using our computational imaging approach, diffractive-refractive optics is an alternative candidate to build light efficient and thin optics for white light imaging.

  15. Computational imaging using lightweight diffractive-refractive optics

    KAUST Repository

    Peng, Yifan; Fu, Qiang; Amata, Hadi; Su, Shuochen; Heide, Felix; Heidrich, Wolfgang

    2015-01-01

    Diffractive optical elements (DOE) show great promise for imaging optics that are thinner and more lightweight than conventional refractive lenses while preserving their light efficiency. Unfortunately, severe spectral dispersion currently limits the use of DOEs in consumer-level lens design. In this article, we jointly design lightweight diffractive-refractive optics and post-processing algorithms to enable imaging under white light illumination. Using the Fresnel lens as a general platform, we show three phase-plate designs, including a super-thin stacked plate design, a diffractive-refractive-hybrid lens, and a phase coded-aperture lens. Combined with cross-channel deconvolution algorithm, both spherical and chromatic aberrations are corrected. Experimental results indicate that using our computational imaging approach, diffractive-refractive optics is an alternative candidate to build light efficient and thin optics for white light imaging.

  16. Experimental Validation of a Dynamic Model for Lightweight Robots

    Directory of Open Access Journals (Sweden)

    Alessandro Gasparetto

    2013-03-01

    Full Text Available Nowadays, one of the main topics in robotics research is dynamic performance improvement by means of a lightening of the overall system structure. The effective motion and control of these lightweight robotic systems occurs with the use of suitable motion planning and control process. In order to do so, model-based approaches can be adopted by exploiting accurate dynamic models that take into account the inertial and elastic terms that are usually neglected in a heavy rigid link configuration. In this paper, an effective method for modelling spatial lightweight industrial robots based on an Equivalent Rigid Link System approach is considered from an experimental validation perspective. A dynamic simulator implementing the formulation is used and an experimental test-bench is set-up. Experimental tests are carried out with a benchmark L-shape mechanism.

  17. Light-weight analyzer for odor recognition

    Energy Technology Data Exchange (ETDEWEB)

    Vass, Arpad A; Wise, Marcus B

    2014-05-20

    The invention provides a light weight analyzer, e.g., detector, capable of locating clandestine graves. The detector utilizes the very specific and unique chemicals identified in the database of human decompositional odor. This detector, based on specific chemical compounds found relevant to human decomposition, is the next step forward in clandestine grave detection and will take the guess-work out of current methods using canines and ground-penetrating radar, which have historically been unreliable. The detector is self contained, portable and built for field use. Both visual and auditory cues are provided to the operator.

  18. Lightweight methodology to improve web accessibility

    CSIR Research Space (South Africa)

    Greeff, M

    2009-10-01

    Full Text Available to improve score. Colour Contrast Fujitsu ColorSelector [9] Each colour combination has to be selected manually. Didn’t identify colour contrast problems that were highlighted by the other two tools. JuicyStudio Colour Contrast Analyser Firefox..., but this is not tested by AccessKeys AccessColor. However, AccessKeys AccessColor provides a link to the specific line in the code where the problem occurs. This is not provided by JuicyStudio Colour Contrast Analyser. According to these two tools, many colour...

  19. Views of college students on plastic surgery.

    Science.gov (United States)

    Ahmad, Muhammad; Mohmand, Humayun; Ahmad, Nabila

    2013-06-01

    Various studies have been conducted in many countries to determine the perception/awareness about plastic surgery. The present study assessed the views of college students about plastic surgery. A questionnaire consisted of nine questions regarding the basic knowledge about plastic surgery was randomly distributed among college students. The students were given 20 minutes to fill out the forms. A total of 250 male and 250 female college students were randomly included in the study. The mean age of the male students was 21.1 years as compared to 20.7 years of female students. The top five conditions named were related to hair (89.8%) followed by face scars (88%). The most common procedure named by the students was liposuction (88.2%) followed by hair transplantation. 80.2% of the students opted not to be a plastic surgeon if given an opportunity to select the profession. 33.8% of the students had seen some kinds of plastic surgery operation. Only 5.6% of the students (3.4% male and 2.2% female) had seen some kinds of plastic surgery procedure. 68% of male students and 48% of female students wished to have a plastic surgery procedure sometime in their lives. Majority of the students (88%) got the information from the internet. The second most common source was magazines (85.2%). Majority of the students (53.4%) had an idea of an invisible scar as a result of having a plastic surgery procedure. Only 22% thought to have no scar. Late Michael Jackson was at the top of the list of celebrities having a plastic surgery procedure (97.8%) followed by Nawaz Shariff (92.4%). Despite the rapid growth of plastic surgery in the last two decades, a large portion of population remains unaware of the spatiality. It is essential to institute programs to educate healthcare consumers and providers about the plastic surgery.

  20. Plastic Pollution from Ships

    OpenAIRE

    Čulin, Jelena; Bielić, Toni

    2016-01-01

    The environmental impact of shipping on marine environment includes discharge of garbage. Plastic litter is of particular concern due to abundance, resistance to degradation and detrimental effect on marine biota. According to recently published studies, a further research is required to assess human health risk. Monitoring data indicate that despite banning plastic disposal at sea, shipping is still a source of plastic pollution. Some of the measures to combat the problem are discussed.

  1. ENVIRONMENTAL ISSUE-PLASTIC

    OpenAIRE

    Sunita Shakle

    2017-01-01

    Polythene is the most common plastic, the annual global production is approximately 60 million tones, and its primary use is in packing. Plastic bags pollute soil and waters and kill thousands of marine generalize plastic bags are not biodegradable they clog water ways, spoil the land scape and end up in landfills. Where they may take 1000 year or more to break down into ever smaller particals that continue to pollution the soil and water.

  2. Our plastic age

    OpenAIRE

    Thompson, Richard C.; Swan, Shanna H.; Moore, Charles J.; vom Saal, Frederick S.

    2009-01-01

    Within the last few decades, plastics have revolutionized our daily lives. Globally we use in excess of 260 million tonnes of plastic per annum, accounting for approximately 8 per cent of world oil production. In this Theme Issue of Philosophical Transactions of the Royal Society, we describe current and future trends in usage, together with the many benefits that plastics bring to society. At the same time, we examine the environmental consequences resulting from the accumulation of waste pl...

  3. Performance of Lightweight Natural-Fiber Reinforced Concrete

    OpenAIRE

    Hardjasaputra Harianto; Ng Gino; Urgessa Girum; Lesmana Gabriella; Sidharta Steven

    2017-01-01

    Concrete, the most common construction material, has negligible tension capacity. However, a reinforcement material such as natural fibers, can be used to improve the tensile properties of concrete. This paper presents experiments conducted on Super Lightweight Concrete mixed with coconut fibers (SLNFRC). Coconut fibers are regarded as one of the toughest natural fibers to strengthen concrete. Coconut fiber reinforced composites have been considered as a sustainable construction material beca...

  4. 3D-printing of lightweight cellular composites.

    Science.gov (United States)

    Compton, Brett G; Lewis, Jennifer A

    2014-09-10

    A new epoxy-based ink is reported, which enables 3D printing of lightweight cellular composites with controlled alignment of multiscale, high-aspectratio fiber reinforcement to create hierarchical structures inspired by balsa wood. Young's modulus values up to 10 times higher than existing commercially available 3D-printed polymers are attainable, while comparable strength values are maintained. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Lightweight, high-opacity Bible paper by fiber loading

    Science.gov (United States)

    Klaus Doelle; Oliver Heise; John H. Klungness; Said M. AbuBakr

    2000-01-01

    This paper has been prepared in order to discuss Fiber Loading™ for lightweight, high-opacity bible paper. Incorporating fillers within pulp fibers has been subject to research since 1960 (Green et al. 1962, Scallan et al. 1985, Allen et al. 1992). Fiber Loading™ is a method for manufacturing precipitated calcium carbonate (PCC) directly within the pulp processing...

  6. Lightweight, Durable Army Antennas Using Carbon Nanotube Technology

    Science.gov (United States)

    2013-01-01

    may be adjusted by collecting the sheet on a revolving substrate conveyor belt (e.g., Teflon belt ), as shown in figure 15 (12). SEM images of the... designated by other authorized documents. Citation of manufacturer’s or trade names does not constitute an official endorsement or approval of the use...CNT) materials to produce lightweight, flexible, and durable alternatives to existing and future Army antenna designs is explored through fabrication

  7. Tailored Buckling Microlattices as Reusable Light-Weight Shock Absorbers.

    Science.gov (United States)

    Frenzel, Tobias; Findeisen, Claudio; Kadic, Muamer; Gumbsch, Peter; Wegener, Martin

    2016-07-01

    Structures and materials absorbing mechanical (shock) energy commonly exploit either viscoelasticity or destructive modifications. Based on a class of uniaxial light-weight geometrically nonlinear mechanical microlattices and using buckling of inner elements, either a sequence of snap-ins followed by irreversible hysteretic - yet repeatable - self-recovery or multistability is achieved, enabling programmable behavior. Proof-of-principle experiments on three-dimensional polymer microstructures are presented. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Static, Lightweight Includes Resolution for PHP

    NARCIS (Netherlands)

    M.A. Hills (Mark); P. Klint (Paul); J.J. Vinju (Jurgen)

    2014-01-01

    htmlabstractDynamic languages include a number of features that are challenging to model properly in static analysis tools. In PHP, one of these features is the include expression, where an arbitrary expression provides the path of the file to include at runtime. In this paper we present two

  9. Linked Metadata - lightweight semantics for data integration (Invited)

    Science.gov (United States)

    Hendler, J. A.

    2013-12-01

    fly integration may prefer to do more traditional data queries and then convert and link the 'views' returned at retrieval time, providing another means of using the linked data infrastructure without having to convert whole datasets to triples to provide linking. Web companies have been taking advantage of 'lightweight' semantic metadata for search quality and optimization (cf. schema.org), linking networks within and without web sites (cf. Facebook's Open Graph Protocol), and in doing various kinds of advertisement and user modeling across datasets. Scientific metadata, on the other hand, has traditionally been geared at being largescale and highly descriptive, and scientific ontologies have been aimed at high expressivity, essentially providing complex reasoning services rather than the less expressive vocabularies needed for data discovery and simple mappings that can allow humans (or more complex systems) when full scale integration is needed. Although this work is just the beginning for providing integration, as the community creates more and more datasets, discovery of these data resources on the Web becomes a crucial starting place. Simple descriptors, that can be combined with textual fields and/or common community vocabularies, can be a great starting place on bringing scientific data into the Web of Data that is growing in other communities. References: [1] Pouchard, Line C., et al. "A Linked Science investigation: enhancing climate change data discovery with semantic technologies." Earth science informatics 6.3 (2013): 175-185.

  10. Plasticity: modeling & computation

    National Research Council Canada - National Science Library

    Borja, Ronaldo Israel

    2013-01-01

    .... "Plasticity Modeling & Computation" is a textbook written specifically for students who want to learn the theoretical, mathematical, and computational aspects of inelastic deformation in solids...

  11. Synaptic Plasticity and Nociception

    Institute of Scientific and Technical Information of China (English)

    ChenJianguo

    2004-01-01

    Synaptic plasticity is one of the fields that progresses rapidly and has a lot of success in neuroscience. The two major types of synaptie plasticity: long-term potentiation ( LTP and long-term depression (LTD are thought to be the cellular mochanisms of learning and memory. Recently, accumulating evidence suggests that, besides serving as a cellular model for learning and memory, the synaptic plasticity involves in other physiological or pathophysiological processes, such as the perception of pain and the regulation of cardiovascular system. This minireview will focus on the relationship between synaptic plasticity and nociception.

  12. Plastics and health risks.

    Science.gov (United States)

    Halden, Rolf U

    2010-01-01

    By 2010, the worldwide annual production of plastics will surpass 300 million tons. Plastics are indispensable materials in modern society, and many products manufactured from plastics are a boon to public health (e.g., disposable syringes, intravenous bags). However, plastics also pose health risks. Of principal concern are endocrine-disrupting properties, as triggered for example by bisphenol A and di-(2-ethylhexyl) phthalate (DEHP). Opinions on the safety of plastics vary widely, and despite more than five decades of research, scientific consensus on product safety is still elusive. This literature review summarizes information from more than 120 peer-reviewed publications on health effects of plastics and plasticizers in lab animals and humans. It examines problematic exposures of susceptible populations and also briefly summarizes adverse environmental impacts from plastic pollution. Ongoing efforts to steer human society toward resource conservation and sustainable consumption are discussed, including the concept of the 5 Rs--i.e., reduce, reuse, recycle, rethink, restrain--for minimizing pre- and postnatal exposures to potentially harmful components of plastics.

  13. Nanoparticles from Degradation of Biodegradable Plastic Mulch

    Science.gov (United States)

    Flury, Markus; Sintim, Henry; Bary, Andy; English, Marie; Schaefer, Sean

    2017-04-01

    Plastic mulch films are commonly used in crop production. They provide multiple benefits, including control of weeds and insects, increase of soil and air temperature, reduction of evaporation, and prevention of soil erosion. The use of plastic mulch film in agriculture has great potential to increase food production and security. Plastic mulch films must be retrieved and disposed after usage. Biodegradable plastic mulch films, who can be tilled into the soil after usage offer great benefits as alternative to conventional polyethylene plastic. However, it has to be shown that the degradation of these mulches is complete and no micro- and nanoparticles are released during degradation. We conducted a field experiment with biodegradable mulches and tested mulch degradation. Mulch was removed from the field after the growing season and composted to facilitate degradation. We found that micro- and nanoparticles were released during degradation of the mulch films in compost. This raises concerns about degradation in soils as well.

  14. The Development of Lightweight Commercial Vehicle Wheels Using Microalloying Steel

    Science.gov (United States)

    Lu, Hongzhou; Zhang, Lilong; Wang, Jiegong; Xuan, Zhaozhi; Liu, Xiandong; Guo, Aimin; Wang, Wenjun; Lu, Guimin

    Lightweight wheels can reduce weight about 100kg for commercial vehicles, and it can save energy and reduce emission, what's more, it can enhance the profits for logistics companies. The development of lightweight commercial vehicle wheels is achieved by the development of new steel for rim, the process optimization of flash butt welding, and structure optimization by finite element methods. Niobium micro-alloying technology can improve hole expansion rate, weldability and fatigue performance of wheel steel, and based on Niobium micro-alloying technology, a special wheel steel has been studied whose microstructure are Ferrite and Bainite, with high formability and high fatigue performance, and stable mechanical properties. The content of Nb in this new steel is 0.025% and the hole expansion rate is ≥ 100%. At the same time, welding parameters including electric upsetting time, upset allowance, upsetting pressure and flash allowance are optimized, and by CAE analysis, an optimized structure has been attained. As a results, the weight of 22.5in×8.25in wheel is up to 31.5kg, which is most lightweight comparing the same size wheels. And its functions including bending fatigue performance and radial fatigue performance meet the application requirements of truck makers and logistics companies.

  15. Impact of lightweight and conventional jackhammers on the operator.

    Science.gov (United States)

    Campbell-Kyureghyan, Naira; Singh, Gurjeet; Otieno, Wilkistar; Cooper, Karen

    2012-01-01

    Jackhammer manufacturers have recently developed lightweight (45-60 lbs) jackhammers intended to reduce the required lifting and pushing forces during operation. However, the vibration characteristics of the lightweight jackhammers and their effect on muscle activity are currently unknown. The objective of this study was to compare the measured vibration and muscle activity between: (i) conventional (90 lb) and light weight (60 lb) jackhammers, (ii) different pavement type/thickness combinations, and (iii) pneumatic and hydraulic jackhammers. Five jackhammers were tested on 4 and 6 inch thick asphalt and concrete pavements by four experienced operators. Analysis of the results revealed that both weight classes averaged 9.7 m/s(2) at the 20 Hz weighted 1/3 octave band frequency, and the TLV of daily exposure for either weight class of jackhammer was less than 1.5 hours/per day. There was an approximately 33% difference in vibration measured on the hand of the operators due to pavement thickness, 30% due pavement type, and no difference due to power source. Conventional jackhammers overall produced higher muscle activity than lightweight jackhammers. Although selection of the correct jackhammer for the job involves many factors including pavement type and thickness, the results of this research can be used to assist in selecting the appropriate jackhammer.

  16. Ceramic/polymer functionally graded material (FGM) lightweight armor system

    Energy Technology Data Exchange (ETDEWEB)

    Petrovic, J.J.; McClellan, K.J.

    1998-12-31

    This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Functionally graded material is an enabling technology for lightweight body armor improvements. The objective was to demonstrate the ability to produce functionally graded ceramic-polymer and ceramic-metal lightweight armor materials. This objective involved two aspects. The first and key aspect was the development of graded-porosity boron-carbide ceramic microstructures. The second aspect was the development of techniques for liquid infiltration of lightweight metals and polymers into the graded-porosity ceramic. The authors were successful in synthesizing boron-carbide ceramic microstructures with graded porosity. These graded-porosity boron-carbide hot-pressed pieces were then successfully liquid-infiltrated in vacuum with molten aluminum at 1,300 C, and with liquid polymers at room temperature. Thus, they were able to demonstrate the feasibility of producing boron carbide-aluminum and boron carbide-polymer functionally graded materials.

  17. Advantages and challenges of dissimilar materials in automotive lightweight construction

    Science.gov (United States)

    Weberpals, Jan-Philipp; Schmidt, Philipp A.; Böhm, Daniel; Müller, Steffen

    2015-03-01

    The core of future automotive lightweight materials is the joining technology of various material mixes. The type of joining will be essential, particularly in electrified propulsion systems, especially as an improved electrical energy transmission leads to a higher total efficiency of the vehicle. The most evident parts to start the optimization process are the traction battery, the electrical performance modules and the engines. Consequently aluminum plays a very central role for lightweight construction applications. However, the physical-technical requirements of components often require the combination with other materials. Thus the joining of mixed material connections is an essential key technology for many of the current developments, for example in the areas E-Mobility, solar energy and lightweight construction. Due to these advantages mixed material joints are already established in the automotive industry and laser beam remote welding is now a focus technology for mixed material connections. The secret of the laser welding process with mixed materials lies within the different areas of the melting phase diagram depending on the mixing ratio and the cooling down rate. According to that areas with unwanted, prim, intermetallic phases arise in the fusion zone. Therefore, laser welding of mixed material connections can currently only be used with additional filler in the automotive industry.

  18. The utilization of stone ash on cellular lightweight concrete

    Science.gov (United States)

    Karolina, R.; Sianipar, Y. G. C.

    2018-02-01

    Lightweight concrete brick is a brick which made of cement, sand, water, and foam as the basic composition. This brick are divided into 2, based on the foam used such as AAC (Autoclave Aerated Concrete) that use aluminium paste and CLC(Cellular Lightweight Concrete) that use foaming agent from BASF as its foaming material. In this trial, the lightweight brick that are ging to be use are the CLC with foaming agent as its foaming material with the mixture of stone ash that are produced by the Stone Crusher with spesific gravity 2666 kg/m3 as their partly sand substitution . In this research, the stone ash variant that are used are 10%, 15%, and 20% from the amount of sand that planned before. After casting, the result of the 10% will receive a reduction of compressive strength while an increasing in absorption as 25.07% and 39.005% and the 15% variant will recieve a reduction of compressive strength as much as 65.8% and a reduction of absorption as much as 17.441% and the 20% variant will recieve a reduction of compressive strength as much as 67.4% while an increasing of absorption as much as 17.956%.

  19. Lightweight S-Box Architecture for Secure Internet of Things

    Directory of Open Access Journals (Sweden)

    A. Prathiba

    2018-01-01

    Full Text Available Lightweight cryptographic solutions are required to guarantee the security of Internet of Things (IoT pervasiveness. Cryptographic primitives mandate a non-linear operation. The design of a lightweight, secure, non-linear 4 × 4 substitution box (S-box suited to Internet of Things (IoT applications is proposed in this work. The structure of the 4 × 4 S-box is devised in the finite fields GF (24 and GF ((222. The finite field S-box is realized by multiplicative inversion followed by an affine transformation. The multiplicative inverse architecture employs Euclidean algorithm for inversion in the composite field GF ((222. The affine transformation is carried out in the field GF (24. The isomorphic mapping between the fields GF (24 and GF ((222 is based on the primitive element in the higher order field GF (24. The recommended finite field S-box architecture is combinational and enables sub-pipelining. The linear and differential cryptanalysis validates that the proposed S-box is within the maximal security bound. It is observed that there is 86.5% lesser gate count for the realization of sub field operations in the composite field GF ((222 compared to the GF (24 field. In the PRESENT lightweight cipher structure with the basic loop architecture, the proposed S-box demonstrates 5% reduction in the gate equivalent area over the look-up-table-based S-box with TSMC 180 nm technology.

  20. Lightweight Steel Solutions for Automotive Industry

    International Nuclear Information System (INIS)

    Lee, Hong Woo; Kim, Gyosung; Park, Sung Ho

    2010-01-01

    Recently, improvement in fuel efficiency and safety has become the biggest issue in worldwide automotive industry. Although the regulation of environment and safety has been tightened up more and more, the majority of vehicle bodies are still manufactured from stamped steel components. This means that the optimized steel solutions enable to demonstrate its ability to reduce body weight with high crashworthiness performance instead of expensive light weight materials such as Al, Mg and composites. To provide the innovative steel solutions for automotive industry, POSCO has developed AHSS and its application technologies, which is directly connected to EVI activities. EVI is a technical cooperation program with customer covering all stages of new car project from design to mass production. Integrated light weight solutions through new forming technologies such as TWB, hydroforming and HPF are continuously developed and provided for EVI activities. This paper will discuss the detailed status of these technologies especially light weight steel solutions based on innovative technologies.

  1. SLIMarray: Lightweight software for microarray facility management

    Directory of Open Access Journals (Sweden)

    Marzolf Bruz

    2006-10-01

    Full Text Available Abstract Background Microarray core facilities are commonplace in biological research organizations, and need systems for accurately tracking various logistical aspects of their operation. Although these different needs could be handled separately, an integrated management system provides benefits in organization, automation and reduction in errors. Results We present SLIMarray (System for Lab Information Management of Microarrays, an open source, modular database web application capable of managing microarray inventories, sample processing and usage charges. The software allows modular configuration and is well suited for further development, providing users the flexibility to adapt it to their needs. SLIMarray Lite, a version of the software that is especially easy to install and run, is also available. Conclusion SLIMarray addresses the previously unmet need for free and open source software for managing the logistics of a microarray core facility.

  2. Lightweight Combat Vehicle S and T Campaign

    Science.gov (United States)

    2014-10-06

    reducing half- shaft torque requirement, keeping each motor centrally located between each wheel set and providing high drive efficiency. Design ...that could be applied to these components are: 1. Redesign and change the hub, road arm, and spindle away from a solid forged design to hollow cross...X Drivetrain  Topology for gear design o Composite construction (steel teeth pressed onto Al or Mg hub)  Drill axial holes in shafts for

  3. Molding apparatus. [for thermosetting plastic compositions

    Science.gov (United States)

    Heier, W. C. (Inventor)

    1974-01-01

    Apparatus for compression molding of thermosetting plastics compositions including interfitting hollow male and female components is reported. The components are adapted to be compressed to form a rocket nozzle in a cavity. A thermal jacket is provided exteriorly adjacent to the female component for circulating a thermal transfer fluid to effect curing of a thermosetting plastics material being molded. Each of the male and female components is provided with suitable inlets and outlets for circulating a thermal transfer fluid.

  4. Integrating Hebbian and homeostatic plasticity: introduction.

    Science.gov (United States)

    Fox, Kevin; Stryker, Michael

    2017-03-05

    Hebbian plasticity is widely considered to be the mechanism by which information can be coded and retained in neurons in the brain. Homeostatic plasticity moves the neuron back towards its original state following a perturbation, including perturbations produced by Hebbian plasticity. How then does homeostatic plasticity avoid erasing the Hebbian coded information? To understand how plasticity works in the brain, and therefore to understand learning, memory, sensory adaptation, development and recovery from injury, requires development of a theory of plasticity that integrates both forms of plasticity into a whole. In April 2016, a group of computational and experimental neuroscientists met in London at a discussion meeting hosted by the Royal Society to identify the critical questions in the field and to frame the research agenda for the next steps. Here, we provide a brief introduction to the papers arising from the meeting and highlight some of the themes to have emerged from the discussions.This article is part of the themed issue 'Integrating Hebbian and homeostatic plasticity'. © 2017 The Author(s).

  5. Lightweight concrete with Algerian limestone dust. Part II: study on 50% and 100% replacement to normal aggregate at timely age

    Directory of Open Access Journals (Sweden)

    S. Kitouni

    2015-12-01

    Full Text Available Abstract A control lightweight concrete (LWC mixture made with 50% and 100% of limestone as a replacement of coarse aggregates in weight was prepared. Limestone is used for economical and environmental concern. The concrete samples were cured at 65% relative humidity at 20 ºC. The compressive and flexural tensile strengths, elastic modulus and Poisson's ratio of hardened concrete were measured. Laboratory compressive and tensile strength tests results showed that LWC can be produced by the use of limestone. The aim of this study is twofold: one is to design a lightweight concrete with the use of limestone that will provide an advantage of reduction in dead weight of a structure; and second is to obtain a more economical LWC mixture with the use of limestone.

  6. Linking plastic ingestion research with marine wildlife conservation.

    Science.gov (United States)

    Avery-Gomm, Stephanie; Borrelle, Stephanie B; Provencher, Jennifer F

    2018-05-16

    Plastic is an increasingly pervasive marine pollutant. Concomitantly, the number of studies documenting plastic ingestion in wildlife is accelerating. Many of these studies aim to provide a baseline against which future levels of plastic ingestion can be compared, and are motivated by an underlying interest in the conservation of their study species and ecosystems. Although this research has helped to raise the profile of plastic as a pollutant of emerging concern, there is a disconnect between research examining plastic pollution and wildlife conservation. We present ideas to further discussion about how plastic ingestion research could benefit wildlife conservation by prioritising studies that elucidates the significance of plastic pollution as a population-level threat, identifies vulnerable populations, and evaluates strategies for mitigating impacts. The benefit of plastic ingestion research to marine wildlife can be improved by establishing a clearer understanding of how discoveries will be integrated into conservation and policy actions. Copyright © 2018. Published by Elsevier B.V.

  7. Plastic debris in great skua (Stercorarius skua) pellets corresponds to seabird prey species.

    Science.gov (United States)

    Hammer, S; Nager, R G; Johnson, P C D; Furness, R W; Provencher, J F

    2016-02-15

    Plastic is a common item in marine environments. Studies assessing seabird ingestion of plastics have focused on species that ingest plastics mistaken for prey items. Few studies have examined a scavenger and predatory species that are likely to ingest plastics indirectly through their prey items, such as the great skua (Stercorarius skua). We examined 1034 regurgitated pellets from a great skua colony in the Faroe Islands for plastics and found approximately 6% contained plastics. Pellets containing remains of Northern fulmars (Fulmarus glacialis) had the highest prevalence of plastic. Our findings support previous work showing that Northern fulmars have higher loads of plastics than other sympatric species. This study demonstrates that marine plastic debris is transferred from surface feeding seabird species to predatory great skuas. Examination of plastic ingestion in species that do not ingest plastics directly can provide insights into how plastic particles transfer vertically within the food web. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Reconnaissance survey for lightweight and carbon tetrachloride extractable hydrocarbons in the central and eastern basins of Lake Erie: September 1978

    Energy Technology Data Exchange (ETDEWEB)

    Zapotosky, J.E.; White, W.S.

    1980-10-01

    A reconnaissance survey of the central and eastern basins of Lake Erie (22,240 km/sup 2/) was conducted from September 17 to 27, 1978. The survey provided baseline information on natural gas and oil losses from geologic formations, prior to any potential development of natural gas resources beneath the United States portion of the Lake. Lightweight hydrocarbons indicative of natural gas (methane, ethane, propane, isobutane, and n-butane) are introduced into the waters of Lake Erie by escape from geologic formations and by biological/photochemical processes. The geochemical exploration technique of hydrocarbon sniffing provided enough data to reveal significant distribution patterns, approximate concentrations, and potential sources. Twelve sites with elevated lightweight hydrocarbon concentrations had a composition similar to natural gas. In one area of natural gas input, data analysis suggested a potential negative effect of natural gas on phytoplanktonic metabolism (i.e., ethylene concentration). Samples taken for liquid hydrocarbon analysis (carbon tetrachloride extractable hydrocarbons) correlated best with biologically derived lightweight hydrocarbons.

  9. Advanced computational simulation for design and manufacturing of lightweight material components for automotive applications

    Energy Technology Data Exchange (ETDEWEB)

    Simunovic, S.; Aramayo, G.A.; Zacharia, T. [Oak Ridge National Lab., TN (United States); Toridis, T.G. [George Washington Univ., Washington, DC (United States); Bandak, F.; Ragland, C.L. [Dept. of Transportation, Washington, DC (United States)

    1997-04-01

    Computational vehicle models for the analysis of lightweight material performance in automobiles have been developed through collaboration between Oak Ridge National Laboratory, the National Highway Transportation Safety Administration, and George Washington University. The vehicle models have been verified against experimental data obtained from vehicle collisions. The crashed vehicles were analyzed, and the main impact energy dissipation mechanisms were identified and characterized. Important structural parts were extracted and digitized and directly compared with simulation results. High-performance computing played a key role in the model development because it allowed for rapid computational simulations and model modifications. The deformation of the computational model shows a very good agreement with the experiments. This report documents the modifications made to the computational model and relates them to the observations and findings on the test vehicle. Procedural guidelines are also provided that the authors believe need to be followed to create realistic models of passenger vehicles that could be used to evaluate the performance of lightweight materials in automotive structural components.

  10. Lightweight genome viewer: portable software for browsing genomics data in its chromosomal context.

    Science.gov (United States)

    Faith, Jeremiah J; Olson, Andrew J; Gardner, Timothy S; Sachidanandam, Ravi

    2007-09-18

    Lightweight genome viewer (lwgv) is a web-based tool for visualization of sequence annotations in their chromosomal context. It performs most of the functions of larger genome browsers, while relying on standard flat-file formats and bypassing the database needs of most visualization tools. Visualization as an aide to discovery requires display of novel data in conjunction with static annotations in their chromosomal context. With database-based systems, displaying dynamic results requires temporary tables that need to be tracked for removal. lwgv simplifies the visualization of user-generated results on a local computer. The dynamic results of these analyses are written to transient files, which can import static content from a more permanent file. lwgv is currently used in many different applications, from whole genome browsers to single-gene RNAi design visualization, demonstrating its applicability in a large variety of contexts and scales. lwgv provides a lightweight alternative to large genome browsers for visualizing biological annotations and dynamic analyses in their chromosomal context. It is particularly suited for applications ranging from short sequences to medium-sized genomes when the creation and maintenance of a large software and database infrastructure is not necessary or desired.

  11. Lightweight genome viewer: portable software for browsing genomics data in its chromosomal context

    Directory of Open Access Journals (Sweden)

    Gardner Timothy S

    2007-09-01

    Full Text Available Abstract Background Lightweight genome viewer (lwgv is a web-based tool for visualization of sequence annotations in their chromosomal context. It performs most of the functions of larger genome browsers, while relying on standard flat-file formats and bypassing the database needs of most visualization tools. Visualization as an aide to discovery requires display of novel data in conjunction with static annotations in their chromosomal context. With database-based systems, displaying dynamic results requires temporary tables that need to be tracked for removal. Results lwgv simplifies the visualization of user-generated results on a local computer. The dynamic results of these analyses are written to transient files, which can import static content from a more permanent file. lwgv is currently used in many different applications, from whole genome browsers to single-gene RNAi design visualization, demonstrating its applicability in a large variety of contexts and scales. Conclusion lwgv provides a lightweight alternative to large genome browsers for visualizing biological annotations and dynamic analyses in their chromosomal context. It is particularly suited for applications ranging from short sequences to medium-sized genomes when the creation and maintenance of a large software and database infrastructure is not necessary or desired.

  12. State-of-the-Art Report on Fiber-Reinforced Lightweight Aggregate Concrete Masonry

    Directory of Open Access Journals (Sweden)

    Saul Rico

    2017-01-01

    Full Text Available Masonry construction is the most widely used building method in the world. Concrete masonry is relatively low in cost due to the vast availability of aggregates used within the production process. These aggregate materials are not always reliable for structural use. One of the principal issues associated with masonry is the brittleness of the unit. When subject to seismic loads, the brittleness of the masonry magnifies. In regions with high seismic activity and unspecified building codes or standards, masonry housing has developed into a death trap for countless individuals. A common approach concerning the issue associated with the brittle characteristic of masonry is addition of steel reinforcement. However, this can be expensive, highly dependent on skillfulness of labor, and particularly dependent on the quality of available steel. A proposed solution presented in this investigation consists of introducing steel fibers to the lightweight aggregate concrete masonry mix. Previous investigations in the field of lightweight aggregate fiber-reinforced concrete have shown an increase in flexural strength, toughness, and ductility. The outcome of this research project provides invaluable data for the production of a ductile masonry unit capable of withstanding seismic loads for prolonged periods.

  13. GATE Center of Excellence at UAB in Lightweight Materials for Automotive Applications

    Energy Technology Data Exchange (ETDEWEB)

    None

    2011-07-31

    This report summarizes the accomplishments of the UAB GATE Center of Excellence in Lightweight Materials for Automotive Applications. The first Phase of the UAB DOE GATE center spanned the period 2005-2011. The UAB GATE goals coordinated with the overall goals of DOE's FreedomCAR and Vehicles Technologies initiative and DOE GATE program. The FCVT goals are: (1) Development and validation of advanced materials and manufacturing technologies to significantly reduce automotive vehicle body and chassis weight without compromising other attributes such as safety, performance, recyclability, and cost; (2) To provide a new generation of engineers and scientists with knowledge and skills in advanced automotive technologies. The UAB GATE focused on both the FCVT and GATE goals in the following manner: (1) Train and produce graduates in lightweight automotive materials technologies; (2) Structure the engineering curricula to produce specialists in the automotive area; (3) Leverage automotive related industry in the State of Alabama; (4) Expose minority students to advanced technologies early in their career; (5) Develop innovative virtual classroom capabilities tied to real manufacturing operations; and (6) Integrate synergistic, multi-departmental activities to produce new product and manufacturing technologies for more damage tolerant, cost-effective, and lighter automotive structures.

  14. Lightweight monitoring and control system for coal mine safety using REST style.

    Science.gov (United States)

    Cheng, Bo; Cheng, Xin; Chen, Junliang

    2015-01-01

    The complex environment of a coal mine requires the underground environment, devices and miners to be constantly monitored to ensure safe coal production. However, existing coal mines do not meet these coverage requirements because blind spots occur when using a wired network. In this paper, we develop a Web-based, lightweight remote monitoring and control platform using a wireless sensor network (WSN) with the REST style to collect temperature, humidity and methane concentration data in a coal mine using sensor nodes. This platform also collects information on personnel positions inside the mine. We implement a RESTful application programming interface (API) that provides access to underground sensors and instruments through the Web such that underground coal mine physical devices can be easily interfaced to remote monitoring and control applications. We also implement three different scenarios for Web-based, lightweight remote monitoring and control of coal mine safety and measure and analyze the system performance. Finally, we present the conclusions from this study and discuss future work. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  15. Lightweight Data Aggregation Scheme against Internal Attackers in Smart Grid Using Elliptic Curve Cryptography

    Directory of Open Access Journals (Sweden)

    Debiao He

    2017-01-01

    Full Text Available Recent advances of Internet and microelectronics technologies have led to the concept of smart grid which has been a widespread concern for industry, governments, and academia. The openness of communications in the smart grid environment makes the system vulnerable to different types of attacks. The implementation of secure communication and the protection of consumers’ privacy have become challenging issues. The data aggregation scheme is an important technique for preserving consumers’ privacy because it can stop the leakage of a specific consumer’s data. To satisfy the security requirements of practical applications, a lot of data aggregation schemes were presented over the last several years. However, most of them suffer from security weaknesses or have poor performances. To reduce computation cost and achieve better security, we construct a lightweight data aggregation scheme against internal attackers in the smart grid environment using Elliptic Curve Cryptography (ECC. Security analysis of our proposed approach shows that it is provably secure and can provide confidentiality, authentication, and integrity. Performance analysis of the proposed scheme demonstrates that both computation and communication costs of the proposed scheme are much lower than the three previous schemes. As a result of these aforementioned benefits, the proposed lightweight data aggregation scheme is more practical for deployment in the smart grid environment.

  16. Temperature dependence of plastic scintillators

    Science.gov (United States)

    Peralta, L.

    2018-03-01

    Plastic scintillator detectors have been studied as dosimeters, since they provide a cost-effective alternative to conventional ionization chambers. Several articles have reported undesired response dependencies on beam energy and temperature, which provides the motivation to determine appropriate correction factors. In this work, we studied the light yield temperature dependency of four plastic scintillators, BCF-10, BCF-60, BC-404, RP-200A and two clear fibers, BCF-98 and SK-80. Measurements were made using a 50 kVp X-ray beam to produce the scintillation and/or radioluminescence signal. The 0 to 40 °C temperature range was scanned for each scintillator, and temperature coefficients were obtained.

  17. Recrystallization induced plasticity in austenite and ferrite

    International Nuclear Information System (INIS)

    Huang Mingxin; Pineau, André; Bouaziz, Olivier; Vu, Trong-Dai

    2012-01-01

    Highlights: ► Plasticity can be induced by recrystallization in austenite and ferrite. ► Strain rate is proportional to recrystallization kinetics. ► Overall atomic flux selects a preferential direction may be the origin. - Abstract: New experimental evidences are provided to demonstrate that plastic strain can be induced by recrystallization in austenite and ferrite under an applied stress much smaller than their yield stresses. Such Recrystallization Induced Plasticity (RIP) phenomenon occurs because the overall atomic flux during recrystallization follows a preferential direction imposed by the applied stress.

  18. Multiaxis, Lightweight, Computer-Controlled Exercise System

    Science.gov (United States)

    Haynes, Leonard; Bachrach, Benjamin; Harvey, William

    2006-01-01

    The multipurpose, multiaxial, isokinetic dynamometer (MMID) is a computer-controlled system of exercise machinery that can serve as a means for quantitatively assessing a subject s muscle coordination, range of motion, strength, and overall physical condition with respect to a wide variety of forces, motions, and exercise regimens. The MMID is easily reconfigurable and compactly stowable and, in comparison with prior computer-controlled exercise systems, it weighs less, costs less, and offers more capabilities. Whereas a typical prior isokinetic exercise machine is limited to operation in only one plane, the MMID can operate along any path. In addition, the MMID is not limited to the isokinetic (constant-speed) mode of operation. The MMID provides for control and/or measurement of position, force, and/or speed of exertion in as many as six degrees of freedom simultaneously; hence, it can accommodate more complex, more nearly natural combinations of motions and, in so doing, offers greater capabilities for physical conditioning and evaluation. The MMID (see figure) includes as many as eight active modules, each of which can be anchored to a floor, wall, ceiling, or other fixed object. A cable is payed out from a reel in each module to a bar or other suitable object that is gripped and manipulated by the subject. The reel is driven by a DC brushless motor or other suitable electric motor via a gear reduction unit. The motor can be made to function as either a driver or an electromagnetic brake, depending on the required nature of the interaction with the subject. The module includes a force and a displacement sensor for real-time monitoring of the tension in and displacement of the cable, respectively. In response to commands from a control computer, the motor can be operated to generate a required tension in the cable, to displace the cable a required distance, or to reel the cable in or out at a required speed. The computer can be programmed, either locally or via

  19. IPTV Service Framework Based on Secure Authentication and Lightweight Content Encryption for Screen-Migration in Cloud Computing

    Directory of Open Access Journals (Sweden)

    Aymen Abdullah Alsaffar

    2015-01-01

    Full Text Available These days, the advancing of smart devices (e.g. smart phones, tablets, PC, etc. capabilities and the increase of internet bandwidth enables IPTV service provider to extend their services to smart mobile devices. User can just receive their IPTV service using any smart devices by accessing the internet via wireless network from anywhere anytime in the world which is convenience for users. However, wireless network communication has well a known critical security threats and vulnerabilities to user smart devices and IPTV service such as user identity theft, reply attack, MIM attack, and so forth. A secure authentication for user devices and multimedia protection mechanism is necessary to protect both user devices and IPTV services. As result, we proposed framework of IPTV service based on secure authentication mechanism and lightweight content encryption method for screen-migration in Cloud computing. We used cryptographic nonce combined with user ID and password to authenticate user device in any mobile terminal they passes by. In addition we used Lightweight content encryption to protect and reduce the content decode overload at mobile terminals. Our proposed authentication mechanism reduces the computational processing by 30% comparing to other authentication mechanism and our lightweight content encryption reduces encryption delay to 0.259 second.

  20. Cryogenic Piezo Actuators for Lightweight, Large Aperture, Deployable Membrane Mirrors, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Single crystal piezoelectric actuators are proposed to enable large stroke, high precision, shape control for cryogenic lightweight deployable membrane mirror...

  1. Lightweight Thermally Stable Multi-Meter Aperture Submillimeter Reflectors, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Future astrophysics missions will require lightweight, thermally stable, submillimeter reflectors in sizes of 4m and greater. To date, graphite fiber reinforced...

  2. Direct electroplating of plastic for advanced electrical applications

    DEFF Research Database (Denmark)

    Islam, Aminul; Hansen, Hans Nørgaard; Tang, Peter Torben

    2017-01-01

    Electrodeposition or electroplating is predominantly applied to metallic components. Electroplating of plastics is possible in some cases where an initial electroless plating layer of nickel or copper is made to provide a conductive surface on the plastic part. This paper proposes a method...... for direct electroplating of plastic eliminating the need for slow and expensive processes like electroless metal deposition, PVD coating, painting with conductive inks etc. The results obtained from the test demonstrate the potential of direct electroplating of plastic to enhance the electrical conductivity...... and the use of electroplated plastics for advanced applications like Moulded Interconnect Devices (MIDs)....

  3. CRUX: A compliant robotic upper-extremity exosuit for lightweight, portable, multi-joint muscular augmentation.

    Science.gov (United States)

    Lessard, Steven; Pansodtee, Pattawong; Robbins, Ash; Baltaxe-Admony, Leya Breanna; Trombadore, James M; Teodorescu, Mircea; Agogino, Adrian; Kurniawan, Sri

    2017-07-01

    Wearable robots can potentially offer their users enhanced stability and strength. These augmentations are ideally designed to actuate harmoniously with the user's movements and provide extra force as needed. The creation of such robots, however, is particularly challenging due to the underlying complexity of the human body. In this paper, we present a compliant, robotic exosuit for upper extremities called CRUX. This exosuit, inspired by tensegrity models of the human arm, features a lightweight (1.3 kg), flexible multi-joint design for portable augmentation. We also illustrate how CRUX maintains the full range of motion of the upper-extremities for its users while providing multi-DoF strength amplification to the major muscles of the arm, as evident by tracking the heart rate of an individual exercising said arm. Exosuits such as CRUX may be useful in physical therapy and in extreme environments where users are expected to exert their bodies to the fullest extent.

  4. Mobile, portable lightweight wireless video recording solutions for homeland security, defense, and law enforcement applications

    Science.gov (United States)

    Sandy, Matt; Goldburt, Tim; Carapezza, Edward M.

    2015-05-01

    It is desirable for executive officers of law enforcement agencies and other executive officers in homeland security and defense, as well as first responders, to have some basic information about the latest trend on mobile, portable lightweight wireless video recording solutions available on the market. This paper reviews and discusses a number of studies on the use and effectiveness of wireless video recording solutions. It provides insights into the features of wearable video recording devices that offer excellent applications for the category of security agencies listed in this paper. It also provides answers to key questions such as: how to determine the type of video recording solutions most suitable for the needs of your agency, the essential features to look for when selecting a device for your video needs, and the privacy issues involved with wearable video recording devices.

  5. A Lightweight Continuous Authentication Protocol for the Internet of Things

    Science.gov (United States)

    Chuang, Yo-Hsuan; Yang, Cheng-Ying; Tang, Ssu-Wei

    2018-01-01

    Modern societies are moving toward an information-oriented environment. To gather and utilize information around people’s modern life, tiny devices with all kinds of sensing devices and various sizes of gateways need to be deployed and connected with each other through the Internet or proxy-based wireless sensor networks (WSNs). Within this kind of Internet of Things (IoT) environment, how to authenticate each other between two communicating devices is a fundamental security issue. As a lot of IoT devices are powered by batteries and they need to transmit sensed data periodically, it is necessary for IoT devices to adopt a lightweight authentication protocol to reduce their energy consumption when a device wants to authenticate and transmit data to its targeted peer. In this paper, a lightweight continuous authentication protocol for sensing devices and gateway devices in general IoT environments is introduced. The concept of valid authentication time period is proposed to enhance robustness of authentication between IoT devices. To construct the proposed lightweight continuous authentication protocol, token technique and dynamic features of IoT devices are adopted in order to reach the design goals: the reduction of time consumption for consecutive authentications and energy saving for authenticating devices through by reducing the computation complexity during session establishment of continuous authentication. Security analysis is conducted to evaluate security strength of the proposed protocol. In addition, performance analysis has shown the proposed protocol is a strong competitor among existing protocols for device-to-device authentication in IoT environments. PMID:29621168

  6. A Lightweight Continuous Authentication Protocol for the Internet of Things

    Directory of Open Access Journals (Sweden)

    Yo-Hsuan Chuang

    2018-04-01

    Full Text Available Modern societies are moving toward an information-oriented environment. To gather and utilize information around people’s modern life, tiny devices with all kinds of sensing devices and various sizes of gateways need to be deployed and connected with each other through the Internet or proxy-based wireless sensor networks (WSNs. Within this kind of Internet of Things (IoT environment, how to authenticate each other between two communicating devices is a fundamental security issue. As a lot of IoT devices are powered by batteries and they need to transmit sensed data periodically, it is necessary for IoT devices to adopt a lightweight authentication protocol to reduce their energy consumption when a device wants to authenticate and transmit data to its targeted peer. In this paper, a lightweight continuous authentication protocol for sensing devices and gateway devices in general IoT environments is introduced. The concept of valid authentication time period is proposed to enhance robustness of authentication between IoT devices. To construct the proposed lightweight continuous authentication protocol, token technique and dynamic features of IoT devices are adopted in order to reach the design goals: the reduction of time consumption for consecutive authentications and energy saving for authenticating devices through by reducing the computation complexity during session establishment of continuous authentication. Security analysis is conducted to evaluate security strength of the proposed protocol. In addition, performance analysis has shown the proposed protocol is a strong competitor among existing protocols for device-to-device authentication in IoT environments.

  7. Mechanical properties of geopolymer lightweight brick with styrofoam pellet

    Science.gov (United States)

    Abdullah, Mohd Mustafa Al Bakri; Tahir, Muhammad Faheem Mohd; Kadir, Aeslina Abdul; Hussin, Kamarudin; Samson, W. Saiful Iskandar W.

    2017-09-01

    The utilization of fly ash in brick as partial replacement of cement is gaining immense importance today, mainly on account of the improvement in the long-term durability of brick combined with ecological benefits. In this research, the lightweight brick was produced by using fly ash (class F) as a main material to replace Ordinary Portland Cement (OPC) in the composition of brick. Class F Fly Ash was mixed with an alkaline activator solution (a mixture of sodium silicate and NaOH), and styrofoam pellet was added to the geopolymer mixture to produce lightweight brick. The brick was prepared in two methods that is wet method and dry method due to different brick composition which is dry method for composition with sand and wet method for composition without sand. The bricks were cured in room temperature at 7 aging days. After 7 days, the compressive strength, water absorption, and density of the brick were investigated, where the optimum ratio for the best bricks has been determined from the lightweight density and has compressive strength more than minimum standard requirement. The best bricks are further produce for curing at 60°C in oven at 28 aging days. Those bricks also were characterized using optical microscope to measure the distribution of styrofoam in brick structure. From the result obtained, the brick that cured at 60°C in oven at 28 aging days has high strength compare to brick that cured in room temperature and at 7 day cured. The water absorption is decreasing as the curing temperature and aging days increased whereas density is increasing.

  8. A Lightweight Continuous Authentication Protocol for the Internet of Things.

    Science.gov (United States)

    Chuang, Yo-Hsuan; Lo, Nai-Wei; Yang, Cheng-Ying; Tang, Ssu-Wei

    2018-04-05

    Modern societies are moving toward an information-oriented environment. To gather and utilize information around people's modern life, tiny devices with all kinds of sensing devices and various sizes of gateways need to be deployed and connected with each other through the Internet or proxy-based wireless sensor networks (WSNs). Within this kind of Internet of Things (IoT) environment, how to authenticate each other between two communicating devices is a fundamental security issue. As a lot of IoT devices are powered by batteries and they need to transmit sensed data periodically, it is necessary for IoT devices to adopt a lightweight authentication protocol to reduce their energy consumption when a device wants to authenticate and transmit data to its targeted peer. In this paper, a lightweight continuous authentication protocol for sensing devices and gateway devices in general IoT environments is introduced. The concept of valid authentication time period is proposed to enhance robustness of authentication between IoT devices. To construct the proposed lightweight continuous authentication protocol, token technique and dynamic features of IoT devices are adopted in order to reach the design goals: the reduction of time consumption for consecutive authentications and energy saving for authenticating devices through by reducing the computation complexity during session establishment of continuous authentication. Security analysis is conducted to evaluate security strength of the proposed protocol. In addition, performance analysis has shown the proposed protocol is a strong competitor among existing protocols for device-to-device authentication in IoT environments.

  9. Light-weight spherical mirrors for Cherenkov detectors

    CERN Document Server

    Cisbani, E; Colilli, S; Crateri, R; Cusanno, F; De Leo, R; Fratoni, R; Frullani, S; Garibaldi, F; Giuliani, F; Gricia, M; Iodice, M; Iommi, R; Lagamba, L; Lucentini, M; Mostarda, A; Nappi, E; Pierangeli, L; Santavenere, F; Urciuoli, G M; Vernin, P

    2003-01-01

    Light-weight spherical mirrors have been appositely designed and built for the gas threshold Cherenkov detectors of the two Hall A spectrometers. The mirrors are made of a 1 mm thick aluminized plexiglass sheet, reinforced by a rigid backing consisting of a phenolic honeycomb sandwiched between two carbon fiber mats epoxy glued. The produced mirrors have a thickness equivalent to 0.55% of radiation length, and an optical slope error of about 5.5 mrad. These characteristics make these mirrors suitable for the implementation in Cherenkov threshold detectors. Ways to improve the mirror features are also discussed in view of their possible employment in RICH detectors.

  10. A Lightweight Loudspeaker for Aircraft Communications and Active Noise Control

    Science.gov (United States)

    Warnaka, Glenn E.; Kleinle, Mark; Tsangaris, Parry; Oslac, Michael J.; Moskow, Harry J.

    1992-01-01

    A series of new, lightweight loudspeakers for use on commercial aircraft has been developed. The loudspeakers use NdFeB magnets and aluminum alloy frames to reduce the weight. The NdFeB magnet is virtually encapsulated by steel in the new speaker designs. Active noise reduction using internal loudspeakers was demonstrated to be effective in 1983. A weight, space, and cost efficient method for creating the active sound attenuating fields is to use the existing cabin loudspeakers for both communication and sound attenuation. This will require some additional loudspeaker design considerations.

  11. Lightweight energetic particle detector EPONA and its performance on Giotto

    Energy Technology Data Exchange (ETDEWEB)

    McKenna-Lawlor, S.; Kirsch, E.; Thompson, A.; O' Sullivan, D.; Wenzel, K.-P.

    1987-06-01

    A lightweight energetic particle detector system (EPONA/EPA) is described which was designed to operate in those novel environmental conditions (i) characterised by the varying solar aspect angles and temperatures pertaining during the cruise phase of the Giotto spacecraft and (ii) during the dust bombardment characterising closest approach (approx. 600 km) to the nucleus of comet Halley. Representative data, illustrating the functioning of EPONA during both the Giotto cruise phase and at comet encounter, are represented. The instrument has a wide range of applications to other space experiments where reliable plasma diagnostics are required.

  12. Lightweight approach to model traceability in a CASE tool

    Science.gov (United States)

    Vileiniskis, Tomas; Skersys, Tomas; Pavalkis, Saulius; Butleris, Rimantas; Butkiene, Rita

    2017-07-01

    A term "model-driven" is not at all a new buzzword within the ranks of system development community. Nevertheless, the ever increasing complexity of model-driven approaches keeps fueling all kinds of discussions around this paradigm and pushes researchers forward to research and develop new and more effective ways to system development. With the increasing complexity, model traceability, and model management as a whole, becomes indispensable activities of model-driven system development process. The main goal of this paper is to present a conceptual design and implementation of a practical lightweight approach to model traceability in a CASE tool.

  13. Vascular plasticity in cerebrovascular disorders

    DEFF Research Database (Denmark)

    Edvinsson, Lars I H; Povlsen, Gro Klitgaard

    2011-01-01

    Cerebral ischemia remains a major cause of morbidity and mortality with little advancement in subacute treatment options. This review aims to cover and discuss novel insight obtained during the last decade into plastic changes in the vasoconstrictor receptor profiles of cerebral arteries and micr......Cerebral ischemia remains a major cause of morbidity and mortality with little advancement in subacute treatment options. This review aims to cover and discuss novel insight obtained during the last decade into plastic changes in the vasoconstrictor receptor profiles of cerebral arteries...... therapeutic target for prevention of vasoconstrictor receptor upregulation after stroke. Together, those findings provide new perspectives on the pathophysiology of ischemic stroke and point toward a novel way of reducing vasoconstriction, neuronal cell death, and thus neurologic deficits after stroke....

  14. Research on carbon fiber–reinforced plastic bumper beam subjected to low-velocity frontal impact

    Directory of Open Access Journals (Sweden)

    Yefa Hu

    2015-06-01

    Full Text Available Lightweight and safety performance of automobiles are two important factors for automobile designs. In this article, a research on lightweight and crashworthiness of automotive bumper has been conducted. The carbon fiber–reinforced plastic bumper beam is considered to replace the traditional high-strength steel one. The low-velocity impact finite element simulations for the above two bumper beams are performed via LS-DYNA. Furthermore, the energy absorption capabilities and dynamic response characteristics of the carbon fiber–reinforced plastic bumper beam are investigated and compared with the steel one. The results show that the carbon fiber–reinforced plastic bumper beam is of the better energy absorption capabilities and dynamic response characteristics than those of the steel one; the weight has decreased remarkably close to 50%. Meanwhile, the effect of lay-up and wall thickness on the crashworthiness of the carbon fiber–reinforced plastic bumper beam under low-velocity impact is also studied in this article to select appropriate design schemes.

  15. Medicare Provider Data - Hospice Providers

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Hospice Utilization and Payment Public Use File provides information on services provided to Medicare beneficiaries by hospice providers. The Hospice PUF...

  16. Stem cell plasticity.

    Science.gov (United States)

    Lakshmipathy, Uma; Verfaillie, Catherine

    2005-01-01

    The central dogma in stem cell biology has been that cells isolated from a particular tissue can renew and differentiate into lineages of the tissue it resides in. Several studies have challenged this idea by demonstrating that tissue specific cell have considerable plasticity and can cross-lineage restriction boundary and give rise to cell types of other lineages. However, the lack of a clear definition for plasticity has led to confusion with several reports failing to demonstrate that a single cell can indeed differentiate into multiple lineages at significant levels. Further, differences between results obtained in different labs has cast doubt on some results and several studies still await independent confirmation. In this review, we critically evaluate studies that report stem cell plasticity using three rigid criteria to define stem cell plasticity; differentiation of a single cell into multiple cell lineages, functionality of differentiated cells in vitro and in vivo, robust and persistent engraft of transplanted cells.

  17. Plastics and environment

    International Nuclear Information System (INIS)

    Avenas, P.

    1996-01-01

    Synthetic organic polymers, such as plastics, PVC, polyamides etc are considered less ecological than natural materials such as wood. Other artificial materials such as metals, glass or biodegradable plastics have also a better image than petroleum products. This short paper demonstrates that the manufacturing or the transport of every material uses energy and that the complete energy balance sheet of a plastic bottle, for instance, is more favourable than the one of a glass bottle. Plastic materials are also easily valorized and recycled and part of the energy spent during manufacturing can be recovered during incineration for district heating. During the life-cycle of such a synthetic material, the same petroleum quantity can be used twice which leads to less negative effects on the environment. Finally, the paper focusses on the problem of biodegradable materials which are not degradable when buried under several meters of wastes and which are a nuisance to recycling. (J.S.)

  18. Plastics: Friend or foe?

    Directory of Open Access Journals (Sweden)

    O P Gupta

    2018-01-01

    Full Text Available Plastics has been playing a very significant role in our life. Being light weight, inexpensive and heving good insulating properties it is being used in all aspects of life, from clothes to contact lenses and from mobile phones to automobiles as well as in medical equipments, However it is not biodegradable, and while degrading to fragments it gets converted in to microplastics and nanoplastics The plastic waste is being recognized as an environmental hazard, since these micr- and nanoplastics find way from landfills to water and foods, It is said that we are not only using, but we are eating, drinking and even braething the plastics. These microplastics in body release certain hazardous chemicals and found to be disrupting functions of certain endocrine organs. Whether the rising prevalence of Diabetes, thyroid disorders or infirtility etc., are realated to the plastics?

  19. Recycling of plastics

    Energy Technology Data Exchange (ETDEWEB)

    Kaminsky, W; Menzel, J; Sinn, H

    1976-01-01

    Considering the shortage of raw materials and environmental pollution, the recycling of plastic waste is a very important topic. Pilot plants for research in Funabashi Japan, Franklin (Ohio) U.S.A., and the R 80-process of Krauss Maffei, W. Germany, have demonstrated the possibility of reclaiming plastics from refuse. Old tires and waste from the plastic producing and manufacturing industries are readily available. The pyrolysis of plastic yields gaseous and liquid products, and the exploitation of this cracking reaction has been demonstrated by pilot plants in Japan and Great Britain. Further laboratory scale experiments are taking place in W. Germany. In continuous fluidized beds and in molten salts, polyethylene, polypropylene, polyvinylchloride, polystyrene and rubber are pyrolysed and better than 98 percent conversion is obtained. Up to 40 percent of the feed can be obtained as aromatic compounds, and a pilot plant is under construction. As a first step PVC-containing material can be almost quantitatively dehydrochlorinated.

  20. A Plastic Menagerie

    Science.gov (United States)

    Hadley, Mary Jane

    2010-01-01

    Bobble heads had become quite popular, depicting all sorts of sports figures, animals, and even presidents. In this article, the author describes how her fourth graders made bobble head sculptures out of empty plastic drink bottles. (Contains 1 online resource.)

  1. Art and Plastic Surgery.

    Science.gov (United States)

    Fernandes, Julio Wilson; Metka, Susanne

    2016-04-01

    The roots of science and art of plastic surgery are very antique. Anatomy, drawing, painting, and sculpting have been very important to the surgery and medicine development over the centuries. Artistic skills besides shape, volume, and lines perception can be a practical aid to the plastic surgeons' daily work. An overview about the interactions between art and plastic surgery is presented, with a few applications to rhinoplasty, cleft lip, and other reconstructive plastic surgeries. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

  2. Pregnancy and the Plastic Surgery Resident.

    Science.gov (United States)

    Garza, Rebecca M; Weston, Jane S; Furnas, Heather J

    2017-01-01

    Combining pregnancy with plastic surgery residency has historically been difficult. Two decades ago, 36 percent of plastic surgery program directors surveyed actively discouraged pregnancy among residents, and 33 percent of women plastic surgeons suffered from infertility. Most alarmingly, 26 percent of plastic surgery trainees had had an elective abortion during residency. With increasing numbers of women training in plastic surgery, this historical lack of support for pregnancy deserves further attention. To explore the current accommodations made for the pregnant plastic surgery resident, an electronic survey was sent to 88 plastic surgery program directors in the United States. Fifty-four responded, for a response rate of 61.36 percent. On average, a director trained a total of 7.91 women among 17.28 residents trained over 8.19 years. Of the women residents, 1.43 were pregnant during a director's tenure, with 1.35 of those residents taking maternity leave. An average 1.75 male residents took paternity leave. Approximately one-third of programs had a formal maternity/paternity leave policy (36.54 percent) which, in most cases, was limited to defining allowed weeks of leave, time required to fulfill program requirements, and remuneration during leave. This survey of plastic surgery directors is a first step in defining the challenges training programs face in supporting the pregnant resident. Directors provided comments describing their challenges accommodating an absent resident in a small program and complying with the American Board of Plastic Surgery's required weeks of training per year. A discussion of these challenges is followed by suggested solutions.

  3. DEVELOPMENT OF PLASTIC SURGERY.

    Science.gov (United States)

    Pećanac, Marija Đ

    2015-01-01

    Plastic surgery is a medical specialty dealing with corrections of defects, improvements in appearance and restoration of lost function. Ancient times. The first recorded account of reconstructive plastic surgery was found in ancient Indian Sanskrit texts, which described reconstructive surgeries of the nose and ears. In ancient Greece and Rome, many medicine men performed simple plastic cosmetic surgeries to repair damaged parts of the body caused by war mutilation, punishment or humiliation. In the Middle Ages, the development of all medical braches, including plastic surgery was hindered. New age. The interest in surgical reconstruction of mutilated body parts was renewed in the XVIII century by a great number of enthusiastic and charismatic surgeons, who mastered surgical disciplines and became true artists that created new forms. Modern era. In the XX century, plastic surgery developed as a modern branch in medicine including many types of reconstructive surgery, hand, head and neck surgery, microsurgery and replantation, treatment of burns and their sequelae, and esthetic surgery. Contemporary and future plastic surgery will continue to evolve and improve with regenerative medicine and tissue engineering resulting in a lot of benefits to be gained by patients in reconstruction after body trauma, oncology amputation, and for congenital disfigurement and dysfunction.

  4. Recycling of packing plastics

    International Nuclear Information System (INIS)

    Gintenreiter-Koegl, S.

    2001-05-01

    The ordinance on the avoidance of packaging waste was a serious intervention in the public and private waste management in Austria. Above all the high expenses for an overall packaging waste collection and the recycling of packaging plastics were criticized. The landfill ordinance comes into force in 2004 and this means another major change in the Austrian waste management system. In the course of this change the overall collection and the recycling and recovery of waste streams, especially of the high caloric plastics waste, have to be discussed again. The goal of this work was on the one hand to develop and adapt the hydrocracking process for the recovery of mixed plastics waste and to show a possible application in Austria. On the other hand the work shows the technical, ecological and economical conditions for packaging plastics recycling and recovery in order to find optimum applications for the processes and to examine their contribution to a sustainable development. A hydrocracking test plant for the processing of mixed plastic wastes was built and had been running for about three years. The tests were carried out successfully and the suitability of the technology for the recovery of packaging plastics could be shown. Results show at least a 35 % yield of fuel. The hydrocracking technology is quite common in the oil industries and therefore an integration on a refinery site is suggested. (author)

  5. Optical fabrication of lightweighted 3D printed mirrors

    Science.gov (United States)

    Herzog, Harrison; Segal, Jacob; Smith, Jeremy; Bates, Richard; Calis, Jacob; De La Torre, Alyssa; Kim, Dae Wook; Mici, Joni; Mireles, Jorge; Stubbs, David M.; Wicker, Ryan

    2015-09-01

    Direct Metal Laser Sintering (DMLS) and Electron Beam Melting (EBM) 3D printing technologies were utilized to create lightweight, optical grade mirrors out of AlSi10Mg aluminum and Ti6Al4V titanium alloys at the University of Arizona in Tucson. The mirror prototypes were polished to meet the λ/20 RMS and λ/4 P-V surface figure requirements. The intent of this project was to design topologically optimized mirrors that had a high specific stiffness and low surface displacement. Two models were designed using Altair Inspire software, and the mirrors had to endure the polishing process with the necessary stiffness to eliminate print-through. Mitigating porosity of the 3D printed mirror blanks was a challenge in the face of reconciling new printing technologies with traditional optical polishing methods. The prototypes underwent Hot Isostatic Press (HIP) and heat treatment to improve density, eliminate porosity, and relieve internal stresses. Metal 3D printing allows for nearly unlimited topological constraints on design and virtually eliminates the need for a machine shop when creating an optical quality mirror. This research can lead to an increase in mirror mounting support complexity in the manufacturing of lightweight mirrors and improve overall process efficiency. The project aspired to have many future applications of light weighted 3D printed mirrors, such as spaceflight. This paper covers the design/fab/polish/test of 3D printed mirrors, thermal/structural finite element analysis, and results.

  6. Sustainability assessment of a lightweight biomimetic ceiling structure

    International Nuclear Information System (INIS)

    Antony, Florian; Speck, Thomas; Speck, Olga; Grießhammer, Rainer

    2014-01-01

    An intensive and continuous debate centres on the question of whether biomimetics has a specific potential to contribute to sustainability. In the context of a case study, the objective of this paper is to contribute to this debate by presenting the first systematic approach to assess the sustainability of a complex biomimetic product. The object of inquiry is a lecture hall's ribbed slab. Based on criteria suggested by the Association of German Engineers (VDI), it has been verified that the slab has been correctly defined as biomimetic. Moreover, a systematic comparative product sustainability assessment has been carefully carried out. For purposes of comparison, estimated static calculations have been performed for conceivable current state-of-the-art lightweight ceiling structures. Alternative options are a hollow article slab and a pre-stressed flat slab. Besides a detailed benefit analysis and a discussion of social effects, their costs have also been compared. A particularly detailed life cycle assessment on the respective environmental impacts has also been performed. Results show that the biomimetic ribbed slab built in the 1960s is able to keep up with the current state-of-the-art lightweight solutions in terms of sustainability. These promising results encourage a systematic search for a broad range of sustainable biomimetic solutions. (paper)

  7. Apply lightweight recognition algorithms in optical music recognition

    Science.gov (United States)

    Pham, Viet-Khoi; Nguyen, Hai-Dang; Nguyen-Khac, Tung-Anh; Tran, Minh-Triet

    2015-02-01

    The problems of digitalization and transformation of musical scores into machine-readable format are necessary to be solved since they help people to enjoy music, to learn music, to conserve music sheets, and even to assist music composers. However, the results of existing methods still require improvements for higher accuracy. Therefore, the authors propose lightweight algorithms for Optical Music Recognition to help people to recognize and automatically play musical scores. In our proposal, after removing staff lines and extracting symbols, each music symbol is represented as a grid of identical M ∗ N cells, and the features are extracted and classified with multiple lightweight SVM classifiers. Through experiments, the authors find that the size of 10 ∗ 12 cells yields the highest precision value. Experimental results on the dataset consisting of 4929 music symbols taken from 18 modern music sheets in the Synthetic Score Database show that our proposed method is able to classify printed musical scores with accuracy up to 99.56%.

  8. Mechanically Strong Lightweight Materials for Aerospace Applications (x-aerogels)

    Science.gov (United States)

    Leventis, Nicholas

    2005-01-01

    The X-Aerogel is a new NASA-developed strong lightweight material made by reacting the mesoporous surfaces of 3-D networks of inorganic nanoparticles with polymeric crosslinkers. Since the relative amount of the crosslinker and the backbone are comparable, X-Aerogels can be viewed either as aerogels modified by templated accumulation of polymer on the skeletal nanoparticles, or as nanoporous polymers made by templated casting of polymeric precursors on a nanostructured framework. The most striking feature of X-Aerogels is that for a nominal 3-fold increase in density (still a ultralightweight material), the mechanical strength can be up to 300 times higher than the strength of the underlying native aerogel. Thus, X-Aerogels combine a multiple of the specific compressive strength of steel, with the thermal conductivity of styrofoam. XAerogels have been demonstrated with several polymers such as polyurethanes/polyureas, epoxies and polyolefins, while crosslinking of approximately 35 different oxide aerogels yields a wide variety of dimensionally stable, porous lightweight materials with interesting structural, magnetic and optical properties. X-Aerogels are evaluated for cryogenic rocket fuel storage tanks and for Advanced EVA suits, where they will play the dual role of the thermal insulator/structural material. Along the same lines, major impact is also expected by the use of X-Aerogels in structural components/thermal protection for small satellites, spacecrafts, planetary vehicles and habitats.

  9. A Lightweight Structure Redesign Method Based on Selective Laser Melting

    Directory of Open Access Journals (Sweden)

    Li Tang

    2016-11-01

    Full Text Available The purpose of this paper is to present a new design method of lightweight parts fabricated by selective laser melting (SLM based on the “Skin-Frame” and to explore the influence of fabrication defects on SLM parts with different sizes. Some standard lattice parts were designed according to the Chinese GB/T 1452-2005 standard and manufactured by SLM. Then these samples were tested in an MTS Insight 30 compression testing machine to study the trends of the yield process with different structure sizes. A set of standard cylinder samples were also designed according to the Chinese GB/T 228-2010 standard. These samples, which were made of iron-nickel alloy (IN718, were also processed by SLM, and then tested in the universal material testing machine INSTRON 1346 to obtain their tensile strength. Furthermore, a lightweight redesigned method was researched. Then some common parts such as a stopper and connecting plate were redesigned using this method. These redesigned parts were fabricated and some application tests have already been performed. The compression testing results show that when the minimum structure size is larger than 1.5 mm, the mechanical characteristics will hardly be affected by process defects. The cylinder parts were fractured by the universal material testing machine at about 1069.6 MPa. These redesigned parts worked well in application tests, with both the weight and fabrication time of these parts reduced more than 20%.

  10. Lightweight structure design for wind energy by integrating nanostructured materials

    International Nuclear Information System (INIS)

    Li, Ying; Lu, Jian

    2014-01-01

    Highlights: • Integrate high-strength nano-materials into lightweight design. • Lightweight design scheme for wind turbine tower application. • Expand the bending formulae for tapered tubular structures with varying thickness. • We rewrite the Secant Formula for a tapered beam under eccentric compression. - Abstract: Wind power develops very fast nowadays with high expectation. Although at the mean time, the use of taller towers, however, smacks head-on into the issue of transportability. The engineering base and computational tools have to be developed to match machine size and volume. Consequently the research on the light weight structures of tower is carrying out in the main countries which are actively developing wind energy. This paper reports a new design scheme of light weight structure for wind turbine tower. This design scheme is based on the integration of the nanostructured materials produced by the Surface Mechanical Attrition Treatment (SMAT) process. The objective of this study is to accomplish the weight reduction by optimizing the wall thickness of the tapered tubular structure. The basic methods include the identification of the critical zones and the distribution of the high strength materials according to different necessities. The equivalent strength or stiffness design method and the high strength material properties after SMAT process are combined together. Bending and buckling are two main kinds of static loads concerned in consideration. The study results reveal that there is still enough margin for weight reduction in the traditional wind turbine tower design

  11. LSOT: A Lightweight Self-Organized Trust Model in VANETs

    Directory of Open Access Journals (Sweden)

    Zhiquan Liu

    2016-01-01

    Full Text Available With the advances in automobile industry and wireless communication technology, Vehicular Ad hoc Networks (VANETs have attracted the attention of a large number of researchers. Trust management plays an important role in VANETs. However, it is still at the preliminary stage and the existing trust models cannot entirely conform to the characteristics of VANETs. This work proposes a novel Lightweight Self-Organized Trust (LSOT model which contains trust certificate-based and recommendation-based trust evaluations. Both the supernodes and trusted third parties are not needed in our model. In addition, we comprehensively consider three factor weights to ease the collusion attack in trust certificate-based trust evaluation, and we utilize the testing interaction method to build and maintain the trust network and propose a maximum local trust (MLT algorithm to identify trustworthy recommenders in recommendation-based trust evaluation. Furthermore, a fully distributed VANET scenario is deployed based on the famous Advogato dataset and a series of simulations and analysis are conducted. The results illustrate that our LSOT model significantly outperforms the excellent experience-based trust (EBT and Lightweight Cross-domain Trust (LCT models in terms of evaluation performance and robustness against the collusion attack.

  12. Performance of lightweight large C/SiC mirror

    Science.gov (United States)

    Yui, Yukari Y.; Goto, Ken; Kaneda, Hidehiro; Katayama, Haruyoshi; Kotani, Masaki; Miyamoto, Masashi; Naitoh, Masataka; Nakagawa, Takao; Saruwatari, Hideki; Suganuma, Masahiro; Sugita, Hiroyuki; Tange, Yoshio; Utsunomiya, Shin; Yamamoto, Yasuji; Yamawaki, Toshihiko

    2017-11-01

    Very lightweight mirror will be required in the near future for both astronomical and earth science/observation missions. Silicon carbide is becoming one of the major materials applied especially to large and/or light space-borne optics, such as Herschel, GAIA, and SPICA. On the other hand, the technology of highly accurate optical measurement of large telescopes, especially in visible wavelength or cryogenic circumstances is also indispensable to realize such space-borne telescopes and hence the successful missions. We have manufactured a very lightweight Φ=800mm mirror made of carbon reinforced silicon carbide composite that can be used to evaluate the homogeneity of the mirror substrate and to master and establish the ground testing method and techniques by assembling it as the primary mirror into an optical system. All other parts of the optics model are also made of the same material as the primary mirror. The composite material was assumed to be homogeneous from the mechanical tests of samples cut out from the various areas of the 800mm mirror green-body and the cryogenic optical measurement of the mirror surface deformation of a 160mm sample mirror that is also made from the same green-body as the 800mm mirror. The circumstance and condition of the optical testing facility has been confirmed to be capable for the highly precise optical measurements of large optical systems of horizontal light axis configuration. Stitching measurement method and the algorithm for analysis of the measurement is also under study.

  13. Prospects for microbiological solutions to environmental pollution with plastics.

    Science.gov (United States)

    Krueger, Martin C; Harms, Hauke; Schlosser, Dietmar

    2015-11-01

    Synthetic polymers, commonly named plastics, are among the most widespread anthropogenic pollutants of marine, limnic and terrestrial ecosystems. Disruptive effects of plastics are known to threaten wildlife and exert effects on natural food webs, but signs for and knowledge on plastic biodegradation are limited. Microorganisms are the most promising candidates for an eventual bioremediation of environmental plastics. Laboratory studies have reported various effects of microorganisms on many types of polymers, usually by enzymatic hydrolysis or oxidation. However, most common plastics have proved to be highly recalcitrant even under conditions known to favour microbial degradation. Knowledge on environmental degradation is yet scarcer. With this review, we provide a comprehensive overview of the current knowledge on microbiological degradation of several of the most common plastic types. Furthermore, we illustrate the analytical challenges concerning the evaluation of plastic biodegradation as well as constraints likely standing against the evolution of effective biodegradation pathways.

  14. Multifunctional Structures for High-Energy Lightweight Load-Bearing Storage

    Science.gov (United States)

    Loyselle, Patricia L.

    2018-01-01

    This is a pull-up banner of the Multifunctional Structures for High-Energy Lightweight Load-bearing Storage (M-SHELLS) technology that will be on display at the SciTech Conference in January 2018. Efforts in Multifunctional Structures for High Energy Load-Bearing Storage (M-Shells) are pushing the boundaries of development for hybrid electric propulsion for future commercial aeronautical transport. The M-Shells hybrid material would serve as the power/energy storage of the vehicle and provide structural integrity, freeing up usable volume and mass typically occupied by bulky batteries. The ultimate goal is to demonstrate a system-level mass savings with a multifunctional structure with energy storage.

  15. The Hydrological Performance of Lightweight Green Roofs Made From Recycled Waste Materials As the Drainage Layer

    Directory of Open Access Journals (Sweden)

    Afizah Asman Nurul Shahadahtul

    2017-01-01

    Full Text Available Green roofs can be used for promoting infiltration and provide temporary storage spaces. Hence, in urban stormwater structural design, the investigation of the hydrological performance investigation is often required. Thus, this paper presents the results of a hydrological investigation in term of peak flow reduction and green roof’s weight using 0, 2, and 6% slope for three specimens drainage layer in green roofs. Three types of recycled waste are selected for each test bed which is rubber crumbs, palm oil shell, and polyfoam. Another test bed without a drainage layer as a control. The result indicates that rubber crumbs can be used as a stormwater control and runoff reduction while ensuring a good drainage and aeration of the substrate and roofs. From the results obtained shows that rubber crumbs are suitable as a drainage layer and a proposed slope of 6% are suitable for lightweight green roofs.

  16. Towards a Light-weight Bag-of-tasks Grid Architecture

    Directory of Open Access Journals (Sweden)

    I. Bašičević

    2015-06-01

    Full Text Available The paper presents the application of SIP protocol in the context of bag-of-tasks grid architecture. The SIP protocol has been used in the realization of the execution management service. The main idea is the use of stateful SIP proxy as a request broker. The paper provides a description of the concept, and the prototype system that has been built, as well as the calculation of estimated performance level and its relation to maximum RTT of grid system. The main advantage of this light-weight grid architecture is the reuse of a mature infrastructure. A short overview of some approaches to the mathematical modeling of computer grids is included.

  17. Advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) Small Spacecraft System

    Science.gov (United States)

    Lockett, Tiffany Russell; Martinez, Armando; Boyd, Darren; SanSouice, Michael; Farmer, Brandon; Schneider, Todd; Laue, Greg; Fabisinski, Leo; Johnson, Les; Carr, John A.

    2015-01-01

    This paper describes recent advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) currently being developed at NASA's Marshall Space Flight Center. The LISA-T array comprises a launch stowed, orbit deployed structure on which thin-film photovoltaic (PV) and antenna devices are embedded. The system provides significant electrical power generation at low weights, high stowage efficiency, and without the need for solar tracking. Leveraging high-volume terrestrial-market PVs also gives the potential for lower array costs. LISA-T is addressing the power starvation epidemic currently seen by many small-scale satellites while also enabling the application of deployable antenna arrays. Herein, an overview of the system and its applications are presented alongside sub-system development progress and environmental testing plans.

  18. A lightweight low-frequency sound insulation membrane-type acoustic metamaterial

    Science.gov (United States)

    Lu, Kuan; Wu, Jiu Hui; Guan, Dong; Gao, Nansha; Jing, Li

    2016-02-01

    A novel membrane-type acoustic metamaterial with a high sound transmission loss (STL) at low frequencies (⩽500Hz) was designed and the mechanisms were investigated by using negative mass density theory. This metamaterial's structure is like a sandwich with a thin (thickness=0.25mm) lightweight flexible rubber material within two layers of honeycomb cell plates. Negative mass density was demonstrated at frequencies below the first natural frequency, which results in the excellent low-frequency sound insulation. The effects of different structural parameters of the membrane on the sound-proofed performance at low frequencies were investigated by using finite element method (FEM). The numerical results show that, the STL can be modulated to higher value by changing the structural parameters, such as the membrane surface density, the unite cell film shape, and the membrane tension. The acoustic metamaterial proposed in this study could provide a potential application in the low-frequency noise insulation.

  19. PERFORMANCE EVALUATION OF A LIGHT-WEIGHT MULTI-ECHO LIDAR FOR UNMANNED ROTORCRAFT APPLICATIONS

    Directory of Open Access Journals (Sweden)

    G. Conte

    2013-08-01

    Full Text Available The paper presents a light-weight and low-cost airborne terrain mapping system. The developed Airborne LiDAR Scanner (ALS system consists of a high-precision GNSS receiver, an inertial measurement unit and a magnetic compass which are used to complement a LiDAR sensor in order to compute a digital surface model. Evaluation of the accuracy of the generated surface model is presented. Additionally, a comparison is provided between the surface model generated from the developed ALS system and a model generated using a commercial photogrammetric software. Finally, the multi-echo capability of the used LiDAR sensor is evaluated in areas covered with dense vegetation. The ALS system and camera systems were mounted on-board an industrial unmanned helicopter of around 100 kilograms maximum take-off weight. Presented results are based on real flight-test data.

  20. A Lightweight Authentication and Key Management Scheme for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Danyang Qin

    2016-01-01

    Full Text Available Security problem is one of the most popular research fields in wireless sensor networks for both the application requirement and the resource-constrained essence. An effective and lightweight Authentication and Key Management Scheme (AKMS is proposed in this paper to solve the problem of malicious nodes occurring in the process of networking and to offer a high level of security with low cost. For the condition that the mobile sensor nodes need to be authenticated, the keys in AKMS will be dynamically generated and adopted for security protection. Even when the keys are being compromised or captured, the attackers can neither use the previous keys nor misuse the authenticated nodes to cheat. Simulation results show that the proposed scheme provides more efficient security with less energy consumption for wireless sensor networks especially with mobile sensors.

  1. Lightweight object oriented structure analysis: tools for building tools to analyze molecular dynamics simulations.

    Science.gov (United States)

    Romo, Tod D; Leioatts, Nicholas; Grossfield, Alan

    2014-12-15

    LOOS (Lightweight Object Oriented Structure-analysis) is a C++ library designed to facilitate making novel tools for analyzing molecular dynamics simulations by abstracting out the repetitive tasks, allowing developers to focus on the scientifically relevant part of the problem. LOOS supports input using the native file formats of most common biomolecular simulation packages, including CHARMM, NAMD, Amber, Tinker, and Gromacs. A dynamic atom selection language based on the C expression syntax is included and is easily accessible to the tool-writer. In addition, LOOS is bundled with over 140 prebuilt tools, including suites of tools for analyzing simulation convergence, three-dimensional histograms, and elastic network models. Through modern C++ design, LOOS is both simple to develop with (requiring knowledge of only four core classes and a few utility functions) and is easily extensible. A python interface to the core classes is also provided, further facilitating tool development. © 2014 Wiley Periodicals, Inc.

  2. Social web applications in the city: a lightweight infrastructure for urban computing

    DEFF Research Database (Denmark)

    Hansen, Frank Allan; Grønbæk, Kaj

    2008-01-01

    In this paper, we describe an infrastructure for browsing and multimedia blogging of Web-based information anchored with physical places in an urban environment. The infrastructure is generic in the sense that it may use any means such as GPS, RFID or 2D-barcodes as ubiquitous links anchors...... to anchor Web-based information, blogs, and services in the physical environment. The infrastructure is inspired from earlier work on open hypermedia, in the sense that the anchoring and blogging functionality can be integrated to augment arbitrary Web sites providing information that is relevant to places...... or objects in the physical world. The blog and anchor functionality is implemented as a set of Web services running on a server external to the content server. Experiences and design issues from three cases are discussed, which use Semacode-based physical anchoring to support lightweight urban Web...

  3. 46 CFR 170.200 - Estimated lightweight vertical center of gravity.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Estimated lightweight vertical center of gravity. 170... Centers of Gravity § 170.200 Estimated lightweight vertical center of gravity. (a) Each tank vessel that... calculations required by §§ 170.170 and 172.065, the vertical center of gravity of a tank vessel in the...

  4. Acoustic performance and microstructural analysis of bio-based lightweight concrete containing miscanthus

    NARCIS (Netherlands)

    Chen, Yuxuan; Yu, Q. L.; Brouwers, H. J.H.

    2017-01-01

    Miscanthus Giganteus (i.e. Elephant Grass) is a cost-effective and extensively available ecological resource in many agricultural regions. This article aims at a fundamental research on a bio-based lightweight concrete using miscanthus as aggregate, i.e. miscanthus lightweight concrete (MLC), with

  5. Development of a self-compacting gypsum-based lightweight composite

    NARCIS (Netherlands)

    Yu, Q.; Brouwers, H.J.H.

    2012-01-01

    This article addresses experiments and theories of a self-compacting gypsum-based lightweight composite (SGLC). A ß-hemihydrate is used as binder and lightweight aggregate (LWA, 0–2 mm in different size ranges) is used as aggregate into this composite. The mix of the new composite is designed based

  6. New technologies for the actuation and controls of large aperture lightweight quality mirrors

    Science.gov (United States)

    Lih, S. S.; Yang, E. H.; Gullapalli, S. N.; Flood, R.

    2003-01-01

    This paper presents a set of candidate components: MEMS based large stroke (>100 microns) ultra lightweight (0.01 gm) discrete inch worm actuator technology, and a distributed actuator technology, in the context of a novel lightweight active flexure-hinged substrate concept that uses the nanolaminate face sheet.

  7. Some aspects to improve sound insulation prediction models for lightweight elements

    NARCIS (Netherlands)

    Gerretsen, E.

    2007-01-01

    The best approach to include lightweight building elements in prediction models for airborne and impact sound insulation between rooms, as in EN 12354, is not yet completely clear. Two aspects are at least of importance, i.e. to derive the sound reduction index R for lightweight elements for

  8. Properties and shaping of lightweight ceramics based on phosphate-bonded hollow silica microspheres

    NARCIS (Netherlands)

    With, de G.; Verweij, H.

    1986-01-01

    The values for the Young's modulus, strength, fracture toughness and thermal conductivity of lightweight ceramics based on phosphate-bonded hollow silica microspheres are reported as a function of the processing conditions. They are compared with the relevant data for other lightweight ceramic

  9. A Conservative Formulation for Plasticity

    Science.gov (United States)

    1992-01-01

    concepts that apply to a broad class of macroscopic models: plastic deformation and plastic flow rule. CONSERVATIVE PLASTICITY 469 3a. Plastic Defrrnation...temperature. We illustrate these concepts with a model that has been used to describe high strain-rate plastic flow in metals [11, 31, 32]. In the case...JOURDREN, AND P. VEYSSEYRE. Un Modele ttyperelastique- Plastique Euldrien Applicable aux Grandes Dtformations: Que/ques R~sultats 1-D. preprint, 1991. 2. P

  10. A process chain for integrating piezoelectric transducers into aluminum die castings to generate smart lightweight structures

    Directory of Open Access Journals (Sweden)

    Stefan Stein

    al., [7]. The modules are made of low temperature cofired ceramic (LTCC tapes with an embedded lead zirconate titanate (PZT plate and are manufactured in multilayer technique. For joining conducting copper (Cu wires with the electrode structure of the LPM, a novel laser drop on demand wire bonding method (LDB is applied, which is based on the melting of a spherical CuSn12 braze preform with a liquidus temperature Tliquid of 989.9 °C (Deutsches Kupfer-Institut Düsseldorf, [8] providing sufficient thermal stability for a subsequent casting process. Keywords: Active noise reduction, Laser assisted wire bonding, Smart structures, Piezoelectric transducers, Die casting, Lightweight design

  11. EFFECTS OF LIGHTWEIGHT MULLITE-SILICA RICH GLASS COMPOSITE AGGREGATES ON PROPERTIES OF CASTABLES

    Directory of Open Access Journals (Sweden)

    Li Y.

    2013-09-01

    Full Text Available Mullite-silica rich glass (MSRG composite is a material which is more efficient than chamotte for refractory utilization of clay. The effects of lightweight MSRG composite aggregate on the properties of refractory castables were studied by XRD, SEM and EDS, etc. Comparing with a common lightweight chamotte aggregate, it was found that the hot modulus of rupture, refractoriness under load and thermal shock resistance of the castable with lightweight MSRG aggregate were higher than those of the castable with a common lightweight chamotte aggregate because MSRG did not contain silica crystalline phases and contained a liquid phase with very high viscosity at high temperature. The castables with lightweight chamotte aggregate have higher thermal expansion because of existence of cristobalite and quartz, and have lower thermal conductivity because of higher porosity.

  12. Sustainable fibre materials for replacing plastics in 3D-forming applications

    OpenAIRE

    Jacobsen, Eirik Ulsaker

    2017-01-01

    Plastic is a very broad family of materials that may provide a wide array of mechanical properties depending on the plastic or production method in question. This is why many industries have chosen plastic as their material of choice for the production of anything from plastic bags to underground piping. There is, however, a prominent issue concerning the heavy environmental impact of plastic. This is both due to the processing of crude oil and lack of biodegradability which in turn impact na...

  13. Influence of uncoated and coated plastic waste coarse aggregates to concrete compressive strength

    OpenAIRE

    Purnomo Heru; Pamudji Gandjar; Satim Madsuri

    2017-01-01

    The use of plastic waste as coarse aggregates in concrete is part of efforts to reduce environmental pollution. In one hand the use of plastic as aggregates can provide lighter weight of the concrete than concrete using natural aggregates, but on the other hand bond between plastic coarse aggregates and hard matrix give low concrete compressive strength. Improvement of the bond between plastic coarse aggregate and hard matrix through a sand coating to plastic coarse aggregate whole surface is...

  14. Recycling of plastic: accounting of greenhouse gases and global warming contributions

    DEFF Research Database (Denmark)

    Astrup, Thomas; Fruergaard, Thilde; Christensen, Thomas Højlund

    2009-01-01

    Major greenhouse gas (GHG) emissions related to plastic waste recycling were evaluated with respect to three management alternatives: recycling of clean, single-type plastic, recycling of mixed/contaminated plastic, and use of plastic waste as fuel in industrial processes. Source-separated plasti...... to a mixture of different plastic types and/or contamination, the plastic should be used for energy utilization. Recycling of plastic waste for substitution of other materials such as wood provided no savings with respect to global warming....

  15. High Strength Lightweight Concrete Made with Ternary Mixtures of Cement-Fly Ash-Silica Fume and Scoria as Aggregate

    OpenAIRE

    YAŞAR, Ergül; ATIŞ, Cengiz Duran; KILIÇ, Alaettin

    2014-01-01

    This paper presents part of the results of an ongoing laboratory study carried out to design a structural lightweight high strength concrete (SLWHSC) made with and without ternary mixtures of cement-fly ash-silica fume. In the mixtures, lightweight basaltic-pumice (scoria) aggregate was used. A concrete mixture made with lightweight scoria, and another lightweight scoria concrete mixture incorporating 20% fly ash and 10% silica fume as a cement replacement, were prepared. Two normal...

  16. Energy reduction through voltage scaling and lightweight checking

    Science.gov (United States)

    Kadric, Edin

    As the semiconductor roadmap reaches smaller feature sizes and the end of Dennard Scaling, design goals change, and managing the power envelope often dominates delay minimization. Voltage scaling remains a powerful tool to reduce energy. We find that it results in about 60% geomean energy reduction on top of other common low-energy optimizations with 22nm CMOS technology. However, when voltage is reduced, it becomes easier for noise and particle strikes to upset a node, potentially causing Silent Data Corruption (SDC). The 60% energy reduction, therefore, comes with a significant drop in reliability. Duplication with checking and triple-modular redundancy are traditional approaches used to combat transient errors, but spending 2--3x the energy for redundant computation can diminish or reverse the benefits of voltage scaling. As an alternative, we explore the opportunity to use checking operations that are cheaper than the base computation they are guarding. We devise a classification system for applications and their lightweight checking characteristics. In particular, we identify and evaluate the effectiveness of lightweight checks in a broad set of common tasks in scientific computing and signal processing. We find that the lightweight checks cost only a fraction of the base computation (0-25%) and allow us to recover the reliability losses from voltage scaling. Overall, we show about 50% net energy reduction without compromising reliability compared to operation at the nominal voltage. We use FPGAs (Field-Programmable Gate Arrays) in our work, although the same ideas can be applied to different systems. On top of voltage scaling, we explore other common low-energy techniques for FPGAs: transmission gates, gate boosting, power gating, low-leakage (high-Vth) processes, and dual-V dd architectures. We do not scale voltage for memories, so lower voltages help us reduce logic and interconnect energy, but not memory energy. At lower voltages, memories become dominant

  17. The plasticity of clays

    Science.gov (United States)

    Group, F.F.

    1905-01-01

    (1) Sand injures plasticity little at first because the grains are suspended in a plastic mass. It is only when grains are abundant enough to come in contact with their neighbors, that the effect becomes serious, and then both strength and amount of possible flow are injured. (2) Certain rare organic colloids increase the plasticity by rendering the water viscous. (3) Fineness also tends to increase plasticity. (4) Plane surfaces (plates) increase the amount of possible flow. They also give a chance for lubrication by thinner films, thus increasing the friction of film, and the strength of the whole mass. The action of plates is thus twofold ; but fineness may be carried to such an extent as to break up plate-like grains into angular fragments. The beneficial effects of plates are also decreased by the fact that each is so closely surrounded by others in the mass. (5) Molecular attraction is twofold in increasing plasticity. As the attraction increases, the coherence and strength of the mass increase, and the amount of possible deformation before crumbling also increases. Fineness increases this action by requiring more water. Colloids and crystalloids in solution may also increase the attraction. It is thus seen to be more active than any other single factor.

  18. Plastics control paraffin buildup

    Energy Technology Data Exchange (ETDEWEB)

    1965-06-01

    Paraffin buildup in producing oil wells has been virtually eliminated by the use of plastic-coated sucker rods. The payout of the plasticing process is generally reached in less than a year, and the paraffin buildup may be inhibited for 10 yr or longer. Most of the plants applying plastic coatings to sucker rods are now fully automated, though a few still offer the hand-sprayed coating that some operators prefer. The several steps involved are described. The ideal plastic for the job is resistant to chemicals at high and low temperatures, flexible, has good adhesion, abrasion resistance, impact resistance, and a smooth glossy finish. The phenol aldehyde and epoxy resins presently offered by the industry fulfill these specifications very well; the multicoating and multibaking techniques improve their performance. Due to wide variations in the severity of the paraffin problem from one oil field to another, there is no general rule to estimate the possible savings from using plastic-coated sucker rods. The process, however, does appear to do a remarkable job in controlling paraffin buildup wherever it is a problem in producing oil by pump.

  19. Electrical resistivity and rheological properties of sensing bentonite drilling muds modified with lightweight polymer

    Directory of Open Access Journals (Sweden)

    Ahmed S. Mohammed

    2018-03-01

    Full Text Available In this study, the electrical resistivity and rheological properties of a water-based bentonite clay drilling mud modified with the lightweight polymer (guar gum under various temperature were investigated. Based on the experimental and analytical study, the electrical resistivity was identified as the sensing property of the bentonite drilling mud so that the changes in the properties can be monitored in real-time during the construction. The bentonite contents in the drilling muds were varied up to 8% by the weight of water and temperature was varied from 25 °C to 85 °C. The guar gum content (GG% was varied between 0% and 1% by the weight of the drilling mud to modify the rheological properties and enhance the sensing electrical resistivity of the drilling mud. The guar gum and bentonite clay were characterized using thermal gravimetric analysis (TGA. The total weight loss at 800 °C for the bentonite decreased from 12.96% to 0.7%, about 95% reduction, when the bentonite was mixed with 1% of guar gum. The results also showed that 1% guar gum decreased the electrical resistivity of the drilling mud from 50% to 90% based on the bentonite content and the temperature of the drilling mud. The guar gum modification increased the yield point (YP and plastic viscosity (PV by 58% to 230% and 44% to 77% respectively based on the bentonite content and temperature of the drilling mud. The rheological properties of the drilling muds have been correlated to the electrical resistivity of the drilling mud using nonlinear power and hyperbolic relationships. The model predictions agreed well with the experimental results. Hence the performance of the bentonite drilling muds with and without guar gum can be characterized based on the electrical resistivity which can be monitored real-time in the field. Keywords: Bentonite, Polymer (Guar gum, Electrical resistivity, Rheological properties, Temperature, Modeling

  20. Fifty Years of Innovation in Plastic Surgery

    Directory of Open Access Journals (Sweden)

    Richard M Kwasnicki

    2016-03-01

    Full Text Available BackgroundInnovation has molded the current landscape of plastic surgery. However, documentation of this process only exists scattered throughout the literature as individual articles. The few attempts made to profile innovation in plastic surgery have been narrative, and therefore qualitative and inherently biased. Through the implementation of a novel innovation metric, this work aims to identify and characterise the most prevalent innovations in plastic surgery over the last 50 years.MethodsPatents and publications related to plastic surgery (1960 to 2010 were retrieved from patent and MEDLINE databases, respectively. The most active patent codes were identified and grouped into technology areas, which were subsequently plotted graphically against publication data. Expert-derived technologies outside of the top performing patents areas were additionally explored.ResultsBetween 1960 and 2010, 4,651 patents and 43,118 publications related to plastic surgery were identified. The most active patent codes were grouped under reconstructive prostheses, implants, instruments, non-invasive techniques, and tissue engineering. Of these areas and other expert-derived technologies, those currently undergoing growth include surgical instruments, implants, non-invasive practices, transplantation and breast surgery. Innovations related to microvascular surgery, liposuction, tissue engineering, lasers and prostheses have all plateaued.ConclusionsThe application of a novel metric for evaluating innovation quantitatively outlines the natural history of technologies fundamental to the evolution of plastic surgery. Analysis of current innovation trends provides some insight into which technology domains are the most active.

  1. Introducing the International Confederation of Plastic Surgery Societies: ICOPLAST.

    Science.gov (United States)

    Rakhorst, Hinne A; Badran, Hassan; Clarke, Howard M; Cooter, Rodney; Evans, Gregory R D; Kirschbaum, Julio Daniel; Koh, Kyung Suk; Lazier, Carol; Murphy, Robert X; Nakatsuka, Takashi; Piccolo, Nelson Sarto; Perks, Graeme

    2017-09-01

    This article describes the formation of the International Confederation of Plastic Surgery Societies (ICOPLAST) as a novel, transparent, dynamic, and proactive confederation of national plastic surgery societies. ICOPLAST aspires to provide a voice for the entire international community of plastic surgeons. ICOPLAST has been designed to benefit the patient, plastic surgery as a profession, and each individual plastic surgeon. Its principal objective is to enhance international communication, education, and advocacy processes to ultimately improve patient outcomes for plastic surgery patients globally. The new ICOPLAST's focus is to add true value for patients. ICOPLAST's evolution, philosophy, governance, and bylaws are explained and all societies worldwide are encouraged and cordially invited to join. An open and warm invitation is provided. Additional information is found at www.ICOPLAST.org.

  2. Interhemispheric plasticity in humans.

    Science.gov (United States)

    Hortobágyi, Tibor; Richardson, Sarah Pirio; Lomarev, Mikhael; Shamim, Ejaz; Meunier, Sabine; Russman, Heike; Dang, Nguyet; Hallett, Mark

    2011-07-01

    Chronic unimanual motor practice increases the motor output not only in the trained but also in the nonexercised homologous muscle in the opposite limb. We examined the hypothesis that adaptations in motor cortical excitability of the nontrained primary motor cortex (iM1) and in interhemispheric inhibition from the trained to the nontrained M1 mediate this interlimb cross education. Healthy, young volunteers (n=12) performed 1000 submaximal voluntary contractions (MVC) of the right first dorsal interosseus (FDI) at 80% MVC during 20 sessions. Trained FDI's MVC increased 49.9%, and the untrained FDI's MVC increased 28.1%. Although corticospinal excitability in iM1, measured with transcranial magnetic stimulation (TMS) before and after every fifth session, increased 6% at rest, these changes, as those in intracortical inhibition and facilitation, did not correlate with cross education. When weak and strong TMS of iM1 were delivered on a background of a weak and strong muscle contraction, respectively, of the right FDI, excitability of iM1 increased dramatically after 20 sessions. Interhemispheric inhibition decreased 8.9% acutely within sessions and 30.9% chronically during 20 sessions and these chronic reductions progressively became more strongly associated with cross education. There were no changes in force or TMS measures in the trained group's left abductor minimi digiti and there were no changes in the nonexercising control group (n=8). The findings provide the first evidence for plasticity of interhemispheric connections to mediate cross education produced by a simple motor task.

  3. A PRECISE POSITION AND ATTITUDE DETERMINATION SYSTEM FOR LIGHTWEIGHT UNMANNED AERIAL VEHICLES

    Directory of Open Access Journals (Sweden)

    C. Eling

    2013-08-01

    Full Text Available In many unmanned aerial vehicle (UAV applications a direct georeferencing is required. The reason can be that the UAV flies autonomous and must be navigated precisely, or that the UAV performs a remote sensing operation, where the position of the camera has to be known at the moment of the recording. In our application, a project called Mapping on Demand, we are motivated by both of these reasons. The goal of this project is to develop a lightweight autonomously flying UAV that is able to identify and measure inaccessible three-dimensional objects by use of visual information. Due to payload and space limitations, precise position and attitude determination of micro- and mini-sized UAVs is very challenging. The limitations do not only affect the onboard computing capacity, but they are also noticeable when choosing the georeferencing sensors. In this article, we will present a new developed onboard direct georeferencing system which is real-time capable, applicable for lightweight UAVs and provides very precise results (position accuracy σ σ < 0.5 deg. In this system GPS, inertial sensors, magnetic field sensors, a barometer as well as stereo video cameras are used as georeferencing sensors. We will describe the hardware development and will go into details of the implemented software. In this context especially the RTK-GPS software and the concept of the attitude determination by use of inertial sensors, magnetic field sensors as well as an onboard GPS baseline will be highlighted. Finally, results of first field tests as well as an outlook on further developments will conclude this contribution.

  4. Real-Time Single-Frequency GPS/MEMS-IMU Attitude Determination of Lightweight UAVs

    Science.gov (United States)

    Eling, Christian; Klingbeil, Lasse; Kuhlmann, Heiner

    2015-01-01

    In this paper, a newly-developed direct georeferencing system for the guidance, navigation and control of lightweight unmanned aerial vehicles (UAVs), having a weight limit of 5 kg and a size limit of 1.5 m, and for UAV-based surveying and remote sensing applications is presented. The system is intended to provide highly accurate positions and attitudes (better than 5 cm and 0.5∘) in real time, using lightweight components. The main focus of this paper is on the attitude determination with the system. This attitude determination is based on an onboard single-frequency GPS baseline, MEMS (micro-electro-mechanical systems) inertial sensor readings, magnetic field observations and a 3D position measurement. All of this information is integrated in a sixteen-state error space Kalman filter. Special attention in the algorithm development is paid to the carrier phase ambiguity resolution of the single-frequency GPS baseline observations. We aim at a reliable and instantaneous ambiguity resolution, since the system is used in urban areas, where frequent losses of the GPS signal lock occur and the GPS measurement conditions are challenging. Flight tests and a comparison to a navigation-grade inertial navigation system illustrate the performance of the developed system in dynamic situations. Evaluations show that the accuracies of the system are 0.05∘ for the roll and the pitch angle and 0.2∘ for the yaw angle. The ambiguities of the single-frequency GPS baseline can be resolved instantaneously in more than 90% of the cases. PMID:26501281

  5. Lightweight Design and Welding Manufacturing of a Hydrogen Fuel Cell Powered Car’s Chassis

    Directory of Open Access Journals (Sweden)

    Evangelos Ch. Tsirogiannis

    2018-05-01

    Full Text Available The development of the chassis for the hydrogen fuel cell powered car has been involved in the designing and manufacturing aspects, while taking into consideration the mass, strength, stiffness, centre of gravity (COG, and manufacturing cost requirements. Towards this direction, a chassis design is proposed employing a space frame structure and constructed by an aluminium alloy with great strength. The structural design has been derived through the lightweight engineering approaches in conjunction with the part consolidation, Design for Assembly (DFA and Design for Manufacture methods. Moreover, it has been performed in compliance with the safety regulations of the Shell Eco Marathon racing competition. The material’s principal characteristics are the great strength, the low mass, as well as the great workability, machinability, and weldability. Following the national and global environmental issues, the recyclable characteristics of the aluminium alloy are an extra asset. Furthermore, the existence of aluminium alloy manufacturers around the fabricating area provides low cost supply and fast delivery benefits. The integration of the fuel cell powered vehicle is obtained through the designing and the manufacturing processes of the chassis and the parts fitted on the chassis. The manufacturing procedures are described thoroughly; mainly consisting of the cutting and welding processes and the assembling of the parts that are fitted on the chassis. Additionally, the proper welding parameters for the custom chassis design are investigated and are selected after deductive reasoning. The quality control of the weld joints is conducted by non-destructive methods (NDT ensuring the required structural properties of the welds. A combination of the selected material, the specific type of the chassis, and the manufacturing processes lead to construction simplicity in a low manufacturing cost by using the existing laboratory equipment. Furthermore, the

  6. Preparation of lightweight concretes with sewage sludge ash and their properties

    International Nuclear Information System (INIS)

    Lee, Hwa Young

    2010-01-01

    Sewage sludge results from the accumulation of solids from the unit processes of chemical coagulation, flocculation and sedimentation during wastewater treatment. Rapid urbanization in many areas of the world has resulted in a drastic increase of sewage sludge. More than two million tons of sewage sludge resulted from the treatment of urban sewage is produced annually in Korea. The majority of sewage sludge is disposed of conventionally by the landfill or ocean disposal method, both of which create severe environmental pollution. However, increasingly stringent environmental regulations and scarcity of landfill sites have posed disposal problems of sludge. Incineration is a viable alternative providing a means of sludge stabilization resulting in a reduced volume of sterile, odorless and practically inert residue. Accordingly, the development of environment friendly treatment technique of SSA (sewage sludge ash) inevitably produced during incineration of sewage sludge may be urgently required. For this aim, an attempt to manufacture the lightweight concrete has been made using sewage sludge ash and the physical properties have been determined in terms of specific gravity, compressive strength and thermal conductivity. As a result, the density of specimen prepared with SSA was ranged from 0.6 to 1.4g/ cm 3 and the compressive strength was ranged from 20 to 40kg/ cm 2 . As far as the thermal conductivity of specimen was concerned, it was ranged from 0.3 to 0.6 W/ mK depending on material composition which was far less than that of concrete. It was concluded that the lightweight concretes prepared with SSA could be applicable to building or construction materials such as insulation board and sound absorption material. (author)

  7. Modification of Lightweight Aggregates’ Microstructure by Used Motor Oil Addition

    Science.gov (United States)

    Franus, Małgorzata; Jozefaciuk, Grzegorz; Bandura, Lidia; Lamorski, Krzysztof; Hajnos, Mieczysław; Franus, Wojciech

    2016-01-01

    An admixture of lightweight aggregate substrates (beidellitic clay containing 10 wt % of natural clinoptilolite or Na-P1 zeolite) with used motor oil (1 wt %–8 wt %) caused marked changes in the aggregates’ microstructure, measured by a combination of mercury porosimetry (MIP), microtomography (MT), and scanning electron microscopy. Maximum porosity was produced at low (1%–2%) oil concentrations and it dropped at higher concentrations, opposite to the aggregates’ bulk density. Average pore radii, measured by MIP, decreased with an increasing oil concentration, whereas larger (MT) pore sizes tended to increase. Fractal dimension, derived from MIP data, changed similarly to the MIP pore radius, while that derived from MT remained unaltered. Solid phase density, measured by helium pycnometry, initially dropped slightly and then increased with the amount of oil added, which was most probably connected to changes in the formation of extremely small closed pores that were not available for He atoms. PMID:28773964

  8. Modification of Lightweight Aggregates’ Microstructure by Used Motor Oil Addition

    Directory of Open Access Journals (Sweden)

    Małgorzata Franus

    2016-10-01

    Full Text Available An admixture of lightweight aggregate substrates (beidellitic clay containing 10 wt % of natural clinoptilolite or Na-P1 zeolite with used motor oil (1 wt %–8 wt % caused marked changes in the aggregates’ microstructure, measured by a combination of mercury porosimetry (MIP, microtomography (MT, and scanning electron microscopy. Maximum porosity was produced at low (1%–2% oil concentrations and it dropped at higher concentrations, opposite to the aggregates’ bulk density. Average pore radii, measured by MIP, decreased with an increasing oil concentration, whereas larger (MT pore sizes tended to increase. Fractal dimension, derived from MIP data, changed similarly to the MIP pore radius, while that derived from MT remained unaltered. Solid phase density, measured by helium pycnometry, initially dropped slightly and then increased with the amount of oil added, which was most probably connected to changes in the formation of extremely small closed pores that were not available for He atoms.

  9. A lightweight target-tracking scheme using wireless sensor network

    International Nuclear Information System (INIS)

    Kuang, Xing-hong; Shao, Hui-he; Feng, Rui

    2008-01-01

    This paper describes a lightweight target-tracking scheme using wireless sensor network, where randomly distributed sensor nodes take responsibility for tracking the moving target based on the acoustic sensing signal. At every localization interval, a backoff timer algorithm is performed to elect the leader node and determine the transmission order of the localization nodes. An adaptive active region size algorithm based on the node density is proposed to select the optimal nodes taking part in localization. An improved particle filter algorithm performed by the leader node estimates the target state based on the selected nodes' acoustic energy measurements. Some refinements such as optimal linear combination algorithm, residual resampling algorithm, Markov chain Monte Carlo method are introduced in the scheme to improve the tracking performance. Simulation results validate the efficiency of the proposed tracking scheme

  10. Development of lightweight radiators for lunar based power systems

    International Nuclear Information System (INIS)

    Juhasz, A.J.; Bloomfield, H.S.

    1994-05-01

    This report discusses application of a new lightweight carbon-carbon (C-C) space radiator technology developed under the NASA Civil-Space Technology Initiative (CSTI) High Capacity Power Program to a 20 kWe lunar based power system. This system comprises a nuclear (SP-100 derivative) heat source, a Closed Brayton Cycle (CBC) power conversion unit with heat rejection by means of a plane radiator. The new radiator concept is based on a C-C composite heat pipe with integrally woven fins and a thin walled metallic liner for containment of the working fluid. Using measured areal specific mass values (1.5 kg/m2) for flat plate radiators, comparative CBC power system mass and performance calculations show significant advantages if conventional heat pipes for space radiators are replaced by the new C-C heat pipe technology

  11. A Lightweight, User-controlled System For The Home

    Directory of Open Access Journals (Sweden)

    Lynne Baillie

    2006-01-01

    Full Text Available This paper explores how we designed, with input from some elderly persons, a multi-agent user-controlled network for the home. The system was designed to support the elderly in living longer at home with minimal support. We describe how our work attempts to tackle issues such as privacy, control of personal space, and enjoyment within the home. As the number of elderly individuals’ increases, a certain amount of information gathering or support may be required to assist the elderly in their homes. However, we strongly believe that we should preserve people’s privacy in their homes and ensure that any artifact we propose is seen as enjoyable, aesthetically pleasing and, most importantly, not stigmatizing. We describe in this paper how a lightweight setup, using a multimodal mobile robot, a PDA, and an interactive television, can assist the elderly in the home in an enjoyable and unobtrusive way.

  12. Flight experience with lightweight, low-power miniaturized instrumentation systems

    Science.gov (United States)

    Hamory, Philip J.; Murray, James E.

    1992-01-01

    Engineers at the NASA Dryden Flight Research Facility (NASA-Dryden) have conducted two flight research programs with lightweight, low-power miniaturized instrumentation systems built around commercial data loggers. One program quantified the performance of a radio-controlled model airplane. The other program was a laminar boundary-layer transition experiment on a manned sailplane. The purpose of this paper is to report NASA-Dryden personnel's flight experience with the miniaturized instrumentation systems used on these two programs. The paper will describe the data loggers, the sensors, and the hardware and software developed to complete the systems. The paper also describes how the systems were used and covers the challenges encountered to make them work. Examples of raw data and derived results will be shown as well. Finally, future plans for these systems will be discussed.

  13. Image Encryption Using a Lightweight Stream Encryption Algorithm

    Directory of Open Access Journals (Sweden)

    Saeed Bahrami

    2012-01-01

    Full Text Available Security of the multimedia data including image and video is one of the basic requirements for the telecommunications and computer networks. In this paper, we consider a simple and lightweight stream encryption algorithm for image encryption, and a series of tests are performed to confirm suitability of the described encryption algorithm. These tests include visual test, histogram analysis, information entropy, encryption quality, correlation analysis, differential analysis, and performance analysis. Based on this analysis, it can be concluded that the present algorithm in comparison to A5/1 and W7 stream ciphers has the same security level, is better in terms of the speed of performance, and is used for real-time applications.

  14. Design of Lightweight e Attendance Prototype Using Raspberry Pi

    International Nuclear Information System (INIS)

    Mohd Dzul Aiman Aslan; Mohamad Safuan Sulaiman; Saaidi Ismail; Mohd Fauzi Haris; Nurbahyah Hamdan; Abdul Muin Abd Rahman

    2014-01-01

    E-Attendance is a system that has been extensively used to record attendance in most of the official ceremony of Nuclear Malaysia. Currently, a computer is used as the client to record the input from the proximity card. However, further study on Raspberry Pi, the single board computer that use system on a chip (SoC) in the current market, discover that it is capable of delivering a simple light task of the e-attendance. With a compact memory and in linux environment, a prototype for lightweight e-attendance is being developed. This prototype of Raspberry Pi is believe to have potential in computer based system of Nuclear Technology such as access control, monitoring system and even robotic assistance. This paper will discuss the design of the prototype that resemble e-attendance to improve the robustness of the system. (author)

  15. Thermal conductivity of newspaper sandwiched aerated lightweight concrete panel

    Energy Technology Data Exchange (ETDEWEB)

    Ng, Soon-Ching; Low, Kaw-Sai [Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Jalan Genting Kelang, Setapak, 53300 Kuala Lumpur, Wilayah Persekutuan (Malaysia)

    2010-12-15

    Investigation on the thermal conductivity of newspaper sandwiched aerated lightweight concrete (ALC) panels is the main purpose of this study. Various densities of ALC panels ranging from 1700, 1400 and 1100 kg/m{sup 3} with three different aerial intensities of newspaper sandwiched were produced. Investigation was limited to the effect of aerial intensity of newspaper sandwiched and the effect of density of ALC on thermal conductivity. It is found that the thermal conductivity of newspaper sandwiched ALC panels reduced remarkably compared to control ALC panels. The reduction was recorded at 18.0%, 21.8% and 20.7% correspond to densities of 1700, 1400 and 1100 kg/m{sup 3} with just a mere 0.05 g/cm{sup 2} aerial intensity of newspaper sandwiched. Newspaper sandwiched has a significant impact on the performance of thermal conductivity of ALC panels based on regression analysis. (author)

  16. Lightweight design of a vertical articulated robot using topology optimization

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Seong Ki; Hong, Jung Ki; Jang, Gang Won [Sejong Univ., Seoul (Korea, Republic of); Kim, Tae Hyun; Park, Jin Kyun; Kim, Sang Hyun [Hyundai Heavy Industries Co., Ltd., Daejeon (Korea, Republic of)

    2012-12-15

    Topology optimization is applied for the lightweight design of three main parts of a vertical articulated robot: a base frame, a lower and a upper frame. Design domains for optimization are set as large solid regions that completely embrace the original parts, which are discretized by using three dimensional solid elements. Design variables are parameterized one to one to the material properties of each element by using the SIMP method. The objective of optimization is set as the multi objective form combining the natural frequencies and mean compliances of a structure for which load steps of interest are selected from the multibody dynamics analysis of a robot. The obtained results of topology optimization are post processed to designs favorable to manufacturability for casting process. The final optimized results are 11.0% (base frame), 12.0% (lower frame) and 10.0% (upper frame) lighter with similar or even higher static and dynamic stiffnesses than the original models.

  17. An Ultra-Lightweight Encryption Scheme in Underwater Acoustic Networks

    Directory of Open Access Journals (Sweden)

    Chunyan Peng

    2016-01-01

    Full Text Available We tackle a fundamental security problem in underwater acoustic networks (UANs. The S-box in the existing block encryption algorithm is more energy consuming and unsuitable for resources-constrained UANs. In this paper, instead of S-box, we present a lightweight, 8-round iteration block cipher algorithm for UANs communication based on chaotic theory and increase the key space by changing the number of iteration round. We further propose secure network architecture of UANs. By analysis, our algorithm can resist brute-force searches and adversarial attacks. Simulation results show that, compared with traditional AES-128 and PRESENT algorithms, our cryptographic algorithm can make a good trade-off between security and overhead, has better energy efficiency, and applies to UANs.

  18. Applications of lightweight composite materials in pulsed rotating electrical generators

    International Nuclear Information System (INIS)

    Walls, W.A.; Maifold, S.M.

    1987-01-01

    Present rotating electrical pulse power generators are limited in energy storage capability, specific energy, and peak power density by the use of iron-magnetic circuits. This paper discusses lightweight and compact iron-core homopolar generators (HPGs) which have attained specific energies of 6 kJ/kg and have the potential to achieve 8 kJ/kg in the near future. Prototype iron based pulsed alternators are the favored choice for high power to mass ratio applications and have estimated peak ratings of 180 kW/kg. In terms of total energy storage capability, these machines are limited to several hundred MJ due to the availability of large steel forgings for rotors and basic design considerations including rotor dynamics, allowable rotor tip speeds, and present high speed current collection technology

  19. A Lightweight Anti-Phishing Technique for Mobile Phone

    Directory of Open Access Journals (Sweden)

    Abdul Abiodun Orunsolu

    2017-12-01

    Full Text Available Mobile phones have become an essential device for accessing the web. This is due to the advantages of portability, lower cost and ease. However, the adoption of mobile phones for online activities is now being challenged by myriads of cybercrimes. One of such crimes is phishing attack. In this work, a lightweight anti-phishing technique is proposed to combat phishing attacks on mobile devices. This is necessary because these mobile platforms have increased the attack surface for phishers while diminishing the effectiveness of existing countermeasures. The proposed approach uses a number of URL behavior to determine the status of a website based on frequency analysis of extracted phishing features from PhishTank. To increase the detection power of unknown pattern, a machine learning algorithm called Support Vector Machine is adopted. The results indicated that the approach is very efficient against phishing sites with negligible false negatives.

  20. Programmable Ultra-Lightweight System Adaptable Radio Satellite Base Station

    Science.gov (United States)

    Varnavas, Kosta; Sims, Herb

    2015-01-01

    With the explosion of the CubeSat, small sat, and nanosat markets, the need for a robust, highly capable, yet affordable satellite base station, capable of telemetry capture and relay, is significant. The Programmable Ultra-Lightweight System Adaptable Radio (PULSAR) is NASA Marshall Space Flight Center's (MSFC's) software-defined digital radio, developed with previous Technology Investment Programs and Technology Transfer Office resources. The current PULSAR will have achieved a Technology Readiness Level-6 by the end of FY 2014. The extensibility of the PULSAR will allow it to be adapted to perform the tasks of a mobile base station capable of commanding, receiving, and processing satellite, rover, or planetary probe data streams with an appropriate antenna.

  1. Vibration Transmission in a Multi-Storey Lightweight Building

    DEFF Research Database (Denmark)

    Niu, Bin; Andersen, Lars Vabbersgaard; Kiel, Nikolaj

    2012-01-01

    This paper develops a parametric modelling and analysis approach to investigate the vibration transmission in lightweight buildings. The main focus of the research is to investigate the influence of geometry and configuration of the building on the vibration transmission. A building with a single...... including floor panels, external and internal wall panels, which are considered as beam-stiffened double-leaf panels. As a view to reduce the modelling and analysis cost, the panels are homogenized into equivalent composite shells with two isotropic skin layers and one orthotropic core layer. The material...... configurations of the building. Some observations can be drawn from the numerical examples: •Several frequency gaps are observed from the frequency response curve. A quite low response is obtained in these gaps due to the absence of structural Eigen modes. •The flanking transmission may play a significant role...

  2. Nanocrystalline Aluminum Truss Cores for Lightweight Sandwich Structures

    Science.gov (United States)

    Schaedler, Tobias A.; Chan, Lisa J.; Clough, Eric C.; Stilke, Morgan A.; Hundley, Jacob M.; Masur, Lawrence J.

    2017-12-01

    Substitution of conventional honeycomb composite sandwich structures with lighter alternatives has the potential to reduce the mass of future vehicles. Here we demonstrate nanocrystalline aluminum-manganese truss cores that achieve 2-4 times higher strength than aluminum alloy 5056 honeycombs of the same density. The scalable fabrication approach starts with additive manufacturing of polymer templates, followed by electrodeposition of nanocrystalline Al-Mn alloy, removal of the polymer, and facesheet integration. This facilitates curved and net-shaped sandwich structures, as well as co-curing of the facesheets, which eliminates the need for extra adhesive. The nanocrystalline Al-Mn alloy thin-film material exhibits high strength and ductility and can be converted into a three-dimensional hollow truss structure with this approach. Ultra-lightweight sandwich structures are of interest for a range of applications in aerospace, such as fairings, wings, and flaps, as well as for the automotive and sports industries.

  3. Method of preparing light-weight plugging mud

    Energy Technology Data Exchange (ETDEWEB)

    Gorskiy, V F; Melnichuk, A N; Vernikovskiy, A N

    1982-01-01

    A method is proposed for preparing a light-weight plugging mud which includes mixing Portland cement on an aqueous suspension of palygorskite. It is distinguished by the fact that in order to improve the quality of the mud and strength of the cement stone with simultaneous decrease in the gas permeability, before mixing the Portland cement, the aqueous suspension of palygorskite is dispersed to stabilization of viscosity, and after mixing the Portland cement, the obtained cement-clay mixture is exposed to additional dispersion under pressure. The ratio of the ingredients is the following (% by mass): Portland cement 32.0-61.0; palygorskite 1.2-2.9; water--the rest.

  4. Lightweight link dimensioning using sFlow sampling

    DEFF Research Database (Denmark)

    de Oliviera Schmidt, Ricardo; Sadre, Ramin; Sperotto, Anna

    2013-01-01

    not be trivial in high-speed links. Aiming scalability, operators often deploy packet sampling on monitoring, but little is known how it affects link dimensioning. In this paper we assess the feasibility of lightweight link dimensioning using sFlow, which is a widely-deployed traffic monitoring tool. We...... implement sFlow sampling algorithm and use a previously proposed and validated dimensioning formula that needs traffic variance. We validate our approach using packet captures from real networks. Results show that the proposed procedure is successful for a range of sampling rates and that, due to randomness...... of sampling algorithm, the error introduced by scaling the traffic variance yields more conservative results that cope with short-term traffic fluctuations....

  5. Light-weight reference-based compression of FASTQ data.

    Science.gov (United States)

    Zhang, Yongpeng; Li, Linsen; Yang, Yanli; Yang, Xiao; He, Shan; Zhu, Zexuan

    2015-06-09

    The exponential growth of next generation sequencing (NGS) data has posed big challenges to data storage, management and archive. Data compression is one of the effective solutions, where reference-based compression strategies can typically achieve superior compression ratios compared to the ones not relying on any reference. This paper presents a lossless light-weight reference-based compression algorithm namely LW-FQZip to compress FASTQ data. The three components of any given input, i.e., metadata, short reads and quality score strings, are first parsed into three data streams in which the redundancy information are identified and eliminated independently. Particularly, well-designed incremental and run-length-limited encoding schemes are utilized to compress the metadata and quality score streams, respectively. To handle the short reads, LW-FQZip uses a novel light-weight mapping model to fast map them against external reference sequence(s) and produce concise alignment results for storage. The three processed data streams are then packed together with some general purpose compression algorithms like LZMA. LW-FQZip was evaluated on eight real-world NGS data sets and achieved compression ratios in the range of 0.111-0.201. This is comparable or superior to other state-of-the-art lossless NGS data compression algorithms. LW-FQZip is a program that enables efficient lossless FASTQ data compression. It contributes to the state of art applications for NGS data storage and transmission. LW-FQZip is freely available online at: http://csse.szu.edu.cn/staff/zhuzx/LWFQZip.

  6. Investigation into Plastic Cards

    Directory of Open Access Journals (Sweden)

    Neringa Stašelytė

    2015-03-01

    Full Text Available The article examines the strength of laminating plastic cards at different lamination temperatures. For investigation purposes, two types of plastic substrate and films have been used. Laminate strength has been tested (CMYK to establish the impact of colours on the strength of laminate. The paper compares inks supplied by two different producers. The colour characteristics of CIE L*a*b* space before and after the lamination process have been found. According to lamination strength and characteristics of the colours, the most suitable inks, temperature and films have been chosen.

  7. Joining by plastic deformation

    DEFF Research Database (Denmark)

    Mori, Ken-ichiro; Bay, Niels; Fratini, Livan

    2013-01-01

    As the scale and complexity of products such as aircraft and cars increase, demand for new functional processes to join mechanical parts grows. The use of plastic deformation for joining parts potentially offers improved accuracy, reliability and environmental safety as well as creating opportuni......As the scale and complexity of products such as aircraft and cars increase, demand for new functional processes to join mechanical parts grows. The use of plastic deformation for joining parts potentially offers improved accuracy, reliability and environmental safety as well as creating...

  8. Conserved role of unc-79 in ethanol responses in lightweight mutant mice.

    Directory of Open Access Journals (Sweden)

    David J Speca

    2010-08-01

    Full Text Available The mechanisms by which ethanol and inhaled anesthetics influence the nervous system are poorly understood. Here we describe the positional cloning and characterization of a new mouse mutation isolated in an N-ethyl-N-nitrosourea (ENU forward mutagenesis screen for animals with enhanced locomotor activity. This allele, Lightweight (Lwt, disrupts the homolog of the Caenorhabditis elegans (C. elegans unc-79 gene. While Lwt/Lwt homozygotes are perinatal lethal, Lightweight heterozygotes are dramatically hypersensitive to acute ethanol exposure. Experiments in C. elegans demonstrate a conserved hypersensitivity to ethanol in unc-79 mutants and extend this observation to the related unc-80 mutant and nca-1;nca-2 double mutants. Lightweight heterozygotes also exhibit an altered response to the anesthetic isoflurane, reminiscent of unc-79 invertebrate mutant phenotypes. Consistent with our initial mapping results, Lightweight heterozygotes are mildly hyperactive when exposed to a novel environment and are smaller than wild-type animals. In addition, Lightweight heterozygotes exhibit increased food consumption yet have a leaner body composition. Interestingly, Lightweight heterozygotes voluntarily consume more ethanol than wild-type littermates. The acute hypersensitivity to and increased voluntary consumption of ethanol observed in Lightweight heterozygous mice in combination with the observed hypersensitivity to ethanol in C. elegans unc-79, unc-80, and nca-1;nca-2 double mutants suggests a novel conserved pathway that might influence alcohol-related behaviors in humans.

  9. Plastic flashtube chambers

    International Nuclear Information System (INIS)

    Frisken, W.R.

    1977-01-01

    A brief discussion is given of the use and operation of plastic flashtube chambers. Gas leaks, electric pulsing, the glow discharge, and readout methods are considered. Three distinct problems with high rate applications deal with resolving time, dead time, and polarization/neutralization of the chamber

  10. Plastic Surgery: Tackling Misconceptions

    African Journals Online (AJOL)

    will succeed. First impressions tend to last, and if young people's first impression of plastic surgeons is that they spend much of their time doing cosmetic surgery then this is a first impression that might be long ... Res 2014;4 Suppl S3:169‑70. Access this article online. Quick Response Code: Website: www.amhsr.org. DOI:.

  11. Biobased Plastics 2012

    NARCIS (Netherlands)

    Bolck, C.H.; Ravenstijn, J.; Molenveld, K.; Harmsen, P.F.H.

    2011-01-01

    Dit boek geeft inzicht in de huidige op de markt verkrijgbare biobased plastics en de te verwachten ontwikkelingen. Er wordt gekeken naar zowel thermoplastische als thermohardende materialen. Het boek biedt inzicht in de productie, verwerking en eigenschappen van de verschillende types. Daarnaast

  12. New plastic recycling technology

    Science.gov (United States)

    Greater than 60% of the total plastic content of municipal solid waste is comprised of polyolefins (high-density, low-density, and linear polyethylene and polypropylene. Polyethylene (PE) is the largest-volume component but presents a challenge due to the absence of low-energy de...

  13. Reliability of Plastic Slabs

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    1989-01-01

    In the paper it is shown how upper and lower bounds for the reliability of plastic slabs can be determined. For the fundamental case it is shown that optimal bounds of a deterministic and a stochastic analysis are obtained on the basis of the same failure mechanisms and the same stress fields....

  14. Plasticity in the Drosophila larval visual System

    Directory of Open Access Journals (Sweden)

    Abud J Farca-Luna

    2013-07-01

    Full Text Available The remarkable ability of the nervous system to modify its structure and function is mostly experience and activity modulated. The molecular basis of neuronal plasticity has been studied in higher behavioral processes, such as learning and memory formation. However, neuronal plasticity is not restricted to higher brain functions, but may provide a basic feature of adaptation of all neural circuits. The fruit fly Drosophila melanogaster provides a powerful genetic model to gain insight into the molecular basis of nervous system development and function. The nervous system of the larvae is again a magnitude simpler than its adult counter part, allowing the genetic assessment of a number of individual genetically identifiable neurons. We review here recent progress on the genetic basis of neuronal plasticity in developing and functioning neural circuits focusing on the simple visual system of the Drosophila larva.

  15. On fracture in finite strain gradient plasticity

    DEFF Research Database (Denmark)

    Martínez Pañeda, Emilio; Niordson, Christian Frithiof

    2016-01-01

    In this work a general framework for damage and fracture assessment including the effect of strain gradients is provided. Both mechanism-based and phenomenological strain gradient plasticity (SGP) theories are implemented numerically using finite deformation theory and crack tip fields are invest......In this work a general framework for damage and fracture assessment including the effect of strain gradients is provided. Both mechanism-based and phenomenological strain gradient plasticity (SGP) theories are implemented numerically using finite deformation theory and crack tip fields...... are investigated. Differences and similarities between the two approaches within continuum SGP modeling are highlighted and discussed. Local strain hardening promoted by geometrically necessary dislocations (GNDs) in the vicinity of the crack leads to much higher stresses, relative to classical plasticity...... in the multiple parameter version of the phenomenological SGP theory. Since this also dominates the mechanics of indentation testing, results suggest that length parameters characteristic of mode I fracture should be inferred from nanoindentation....

  16. Plastic loads of pipe bends under combined pressure and out-of-plane bending

    International Nuclear Information System (INIS)

    Lee, Kuk Hee; Kim, Yun Jae; Park, Chi Yong; Lee, Sung Ho; Kim, Tae Ryong

    2007-01-01

    Based on three-Dimensional (3-D) FE limit analyses, this paper provides plastic limit and TES(Twice- Elastic-Slope) loads for pipe bends under combined pressure and out-of-plane bending. The plastic limit loads are determined from FE limit analyses based on elastic.perfectly-plastic materials using the small geometry change option, and the FE limit analyses using the large geometry change option provide TES plastic loads. A wide range of parameters related to the bend geometry is considered. Based on the FE results, closed-form approximations of plastic limit and TES plastic load solutions for pipe bends under out-of-plane bending are proposed

  17. Plastic Surgery Response in Natural Disasters.

    Science.gov (United States)

    Chung, Susan; Zimmerman, Amanda; Gaviria, Andres; Dayicioglu, Deniz

    2015-06-01

    Disasters cause untold damage and are often unpredictable; however, with proper preparation, these events can be better managed. The initial response has the greatest impact on the overall success of the relief effort. A well-trained multidisciplinary network of providers is necessary to ensure coordinated care for the victims of these mass casualty disasters. As members of this network of providers, plastic surgeons have the ability to efficiently address injuries sustained in mass casualty disasters and are a valuable member of the relief effort. The skill set of plastic surgeons includes techniques that can address injuries sustained in large-scale emergencies, such as the management of soft-tissue injury, tissue viability, facial fractures, and extremity salvage. An approach to disaster relief, the types of disasters encountered, the management of injuries related to mass casualty disasters, the role of plastic surgeons in the relief effort, and resource management are discussed. In order to improve preparedness in future mass casualty disasters, plastic surgeons should receive training during residency regarding the utilization of plastic surgery knowledge in the disaster setting.

  18. Neuron-glia metabolic coupling and plasticity.

    Science.gov (United States)

    Magistretti, Pierre J

    2006-06-01

    The coupling between synaptic activity and glucose utilization (neurometabolic coupling) is a central physiological principle of brain function that has provided the basis for 2-deoxyglucose-based functional imaging with positron emission tomography (PET). Astrocytes play a central role in neurometabolic coupling, and the basic mechanism involves glutamate-stimulated aerobic glycolysis; the sodium-coupled reuptake of glutamate by astrocytes and the ensuing activation of the Na-K-ATPase triggers glucose uptake and processing via glycolysis, resulting in the release of lactate from astrocytes. Lactate can then contribute to the activity-dependent fuelling of the neuronal energy demands associated with synaptic transmission. An operational model, the 'astrocyte-neuron lactate shuttle', is supported experimentally by a large body of evidence, which provides a molecular and cellular basis for interpreting data obtained from functional brain imaging studies. In addition, this neuron-glia metabolic coupling undergoes plastic adaptations in parallel with adaptive mechanisms that characterize synaptic plasticity. Thus, distinct subregions of the hippocampus are metabolically active at different time points during spatial learning tasks, suggesting that a type of metabolic plasticity, involving by definition neuron-glia coupling, occurs during learning. In addition, marked variations in the expression of genes involved in glial glycogen metabolism are observed during the sleep-wake cycle, with in particular a marked induction of expression of the gene encoding for protein targeting to glycogen (PTG) following sleep deprivation. These data suggest that glial metabolic plasticity is likely to be concomitant with synaptic plasticity.

  19. Literature Review of Shear Performance of Light-weight Steel Framing Wall Panels

    Science.gov (United States)

    Zhang, Zhuangnan; Liu, Shen; Liu, Hong

    2018-03-01

    In this paper, a comprehensive review of light-weight steel framing wall panels was carried out. The structure and force characteristics of light-weight steel framing wall panels were introduced. The testing and theoretical research results on the shear behaviour of light-weight steel framing wall panels were summarized in the domestic and foreign. And combined with the existing standards in China, the author's views and ideas are put forward to the problems in the research field of this kind of structural system.

  20. Mechanical and Physical Properties of Hydrophobized Lightweight Aggregate Concrete with Sewage Sludge.

    Science.gov (United States)

    Suchorab, Zbigniew; Barnat-Hunek, Danuta; Franus, Małgorzata; Łagód, Grzegorz

    2016-04-27

    This article is focused on lightweight aggregate-concrete modified by municipal sewage sludge and lightweight aggregate-concrete obtained from light aggregates. The article presents laboratory examinations of material physical parameters. Water absorptivity of the examined material was decreased by the admixture of water emulsion of reactive polysiloxanes. Water transport properties were determined using Time Domain Reflectometry, an indirect technique for moisture detection in porous media. Together with basic physical parameters, the heat conductivity coefficient λ was determined for both types of lightweight aggregate-concrete. Analysis of moisture and heat properties of the examined materials confirmed the usefulness of light aggregates supplemented with sewage sludge for prospective production.

  1. Plasticity characteristic obtained by indentation

    International Nuclear Information System (INIS)

    Mil'man, Yu.V.; Chugunova, S.I.; Goncharova, I.V.

    2011-01-01

    Methods for determination plasticity characteristic δH in the measurement of hardness and nanohardness are considered. Parameter δH characterizes the plasticity of a material by the part of plastic deformation in the total elastic-plastic deformation. The value of δH is defined for metals with different types of crystal lattice, covalent and partially covalent crystals, intermetallics, metallic glasses and quasicrystals. It is discussed the dependence of the plasticity characteristic δH on structural factors and temperature. Parameter δH allows to analyze and compare the plasticity of materials which are brittle at standard mechanical tests. The combination of hardness H, as the strength characteristic, and the plasticity characteristic δH makes possible the better characterization of mechanical behavior of materials than only the hardness H. The examples of plasticity characteristic δH application are represented.

  2. Production of Methane and Water from Crew Plastic Waste

    Science.gov (United States)

    Captain, Janine; Santiago, Eddie; Parrish, Clyde; Strayer, Richard F.; Garland, Jay L.

    2008-01-01

    Recycling is a technology that will be key to creating a self sustaining lunar outpost. The plastics used for food packaging provide a source of material that could be recycled to produce water and methane. The recycling of these plastics will require some additional resources that will affect the initial estimate of starting materials that will have to be transported from earth, mainly oxygen, energy and mass. These requirements will vary depending on the recycling conditions. The degredation products of these plastics will vary under different atmospheric conditions. An estimate of the the production rate of methane and water using typical ISRU processes along with the plastic recycling will be presented.

  3. Nondestructive evaluation of reinforced plastics by a radiometric measurement technique

    International Nuclear Information System (INIS)

    Entine, Gerald; Afshari, Sia; Verlinden, Matt

    1990-01-01

    The demand for new high-performance plastics has greatly increased with advances in the performance characteristics of sophisticated reinforced engineering resins. However, conventional methods for the evaluation of the glass and filler contents of reinforced plastics are destructive, labor intensive, and time consuming. We have developed a new instrument, to address this problem, which provides for the rapid, accurate, and nondestructive measurement of glass or filler content in reinforced plastics. This instrument utilizes radiation transmission and scattering techniques for analytical measurement of glass, graphite and other fillers used in reinforced plastics. (author)

  4. Plastic pollutants in water environment

    OpenAIRE

    Mrowiec Bożena

    2017-01-01

    Nowadays, wide applications of plastics result in plastic waste being present in the water environment in a wide variety of sizes. Plastic wastes are in water mainly as microplastics (the size range of 1 nm to < 5 mm). Microplastics have been recognized as an emerging threat, as well as ecotoxicological and ecological risk for water ecosystems. In this review are presented some of the physicochemical properties of plastic materials that determine their toxic effect on the aquatic environment....

  5. Social Media and the Plastic Surgery Patient.

    Science.gov (United States)

    Sorice, Sarah C; Li, Alexander Y; Gilstrap, Jarom; Canales, Francisco L; Furnas, Heather J

    2017-11-01

    Many plastic surgeons use social media as a marketing tool to attract and retain patients, but information about how patients use social media and their preferred types of plastic surgery posts have been lacking. To investigate patients' preferred social media networks and the type of posts they wished to see, a cross-sectional study was conducted in a single aesthetic practice of two plastic surgeons by surveying 100 consecutive patients. The age of the patients averaged 44.4 years (range, 17 to 78 years). Facebook had the greatest patient use and engagement, with YouTube second in use, and Instagram second in number of engaged users. Over half used Pinterest, but with little daily engagement. Only one-fourth used Snapchat, but the percentage of users who were highly engaged was second only to Facebook. The least popular network was Twitter, with the fewest patient users and least engagement. Social media played a minor role compared with the practice's Web site in both influencing patients to choose the practice and providing information on the day of the appointment. Patients most wanted to see posts on a plastic surgeon's social media platform related to practice information, before-and-after photographs, and contests. Articles about plastic surgery held the least interest. Among five types of Web site content, patients expressed most interest in before-and-after photographs. This study is the first to articulate the plastic surgery patient perspective regarding social media. The findings aim to help plastic surgeons maximize their influence on their target audience.

  6. "Oriental anthropometry" in plastic surgery

    Directory of Open Access Journals (Sweden)

    Senna-Fernandes Vasco

    2008-01-01

    Full Text Available Background : According to Chinese medicine, the acupuncture-points′ (acupoints locations are proportionally and symmetrically distributed in well-defined compartment zones on the human body surface Oriental Anthropometry" (OA. Acupoints, if considered as aesthetic-loci, might be useful as reference guides in plastic surgery (PS. Aim: This study aimed to use aesthetic-loci as anatomical reference in surgical marking of Aesthetic Plastic Surgery. Method: This was an observational study based on aesthetic surgeries performed in private clinic. This study was based on 106 cases, comprising of 102 women and 4 men, with ages varying from 07 to 73 years, and with heights of between 1.34 m and 1.80 m. Patients were submitted to aesthetic surgical planning by relating aesthetic-loci to conventional surgical marking, including breast surgeries, abdominoplasty, rhytidoplasty, blepharoplasty, and hair implant. The aesthetic-surgical-outcome (ASO of the patients was assessed by a team of plastic surgeons (who were not involved in the surgical procedures over a follow-up period of one year by using a numeric-rating-scale in percentage (% terms. A four-point-verbal-rating-scale was used to record the patients′ opinion of therapeutic-satisfaction (TS. Results: ASO was 75.3 ± 9.4% and TS indicated that most patients (58.5% obtained "good" results. Of the remainder, 38.7% found the results "excellent", and 2.8% found them "fair". Discussion and Conclusion : The data suggested that the use of aesthetic-loci may be a useful tool for PS as an anatomical reference for surgical marking. However, further investigation is required to assess the efficacy of the OA by providing the patients more reliable balance and harmony in facial and body contours surgeries.

  7. Plastic Deformation Characteristics Of AZ31 Magnesium Alloy Sheets At Elevated Temperature

    International Nuclear Information System (INIS)

    Park, Jingee; Lee, Jongshin; You, Bongsun; Choi, Seogou; Kim, Youngsuk

    2007-01-01

    Using lightweight materials is the emerging need in order to reduce the vehicle's energy consumption and pollutant emissions. Being a lightweight material, magnesium alloys are increasingly employed in the fabrication of automotive and electronic parts. Presently, magnesium alloys used in automotive and electronic parts are mainly processed by die casting. The die casting technology allows the manufacturing of parts with complex geometry. However, the mechanical properties of these parts often do not meet the requirements concerning the mechanical properties (e.g. endurance strength and ductility). A promising alternative can be forming process. The parts manufactured by forming could have fine-grained structure without porosity and improved mechanical properties such as endurance strength and ductility. Because magnesium alloy has low formability resulted form its small slip system at room temperature it is usually formed at elevated temperature. Due to a rapid increase of usage of magnesium sheets in automotive and electronic industry it is necessary to assure database for sheet metal formability and plastic yielding properties in order to optimize its usage. Especially, plastic yielding criterion is a critical property to predict plastic deformation of sheet metal parts in optimizing process using CAE simulation. Von-Mises yield criterion generally well predicts plastic deformation of steel sheets and Hill'1979 yield criterion predicts plastic deformation of aluminum sheets. In this study, using biaxial tensile test machine yield loci of AZ31 magnesium alloy sheet were obtained at elevated temperature. The yield loci ensured experimentally were compared with the theoretical predictions based on the Von-Mises, Hill, Logan-Hosford, and Barlat model

  8. Multimodal network design for sustainable household plastic recycling

    NARCIS (Netherlands)

    Bing Xiaoyun, Xiaoyun; Groot, J.J.; Bloemhof, J.M.; Vorst, van der J.G.A.J.

    2013-01-01

    Purpose – This research studies a plastic recycling system from a reverse logistics angle and investigates the potential benefits of a multimodality strategy to the network design of plastic recycling. This research aims to quantify the impact of multimodality on the network, to provide decision

  9. Novel Architecture for a Long-Life, Lightweight Venus Lander

    International Nuclear Information System (INIS)

    Bugby, D.; Seghi, S.; Kroliczek, E.; Pauken, M.

    2009-01-01

    This paper describes a novel concept for an extended lifetime, lightweight Venus lander. Historically, to operate in the 480 deg. C, 90 atm, corrosive, mostly CO 2 Venus surface environment, previous landers have relied on thick Ti spherical outer shells and thick layers of internal insulation. But even the most resilient of these landers operated for only about 2 hours before succumbing to the environment. The goal on this project is to develop an architecture that extends lander lifetime to 20-25 hours and also reduces mass compared to the Pioneer Venus mission architecture. The idea for reducing mass is to: (a) contain the science instruments within a spherical high strength lightweight polymer matrix composite (PMC) tank; (b) surround the PMC tank with an annular shell of high performance insulation pre-pressurized to a level that (after landing) will exceed the external Venus surface pressure; and (c) surround the insulation with a thin Ti outer shell that contains only a net internal pressure, eliminating buckling overdesign mass. The combination of the PMC inner tank and thin Ti outer shell is lighter than a single thick Ti outer shell. The idea for extending lifetime is to add the following three features: (i) an expendable water supply that is placed within the insulation or is contained in an additional vessel within the PMC tank; (ii) a thin spherical evaporator shell placed within the insulation a short radial distance from the outer shell; and (iii) a thin heat-intercepting liquid cooled shield placed inboard of the evaporator shell. These features lower the temperature of the insulation below what it would have been with the insulation alone, reducing the internal heat leak and lengthening lifetime. The use of phase change materials (PCMs) inside the PMC tank is also analyzed as a lifetime-extending design option. The paper describes: (1) analytical modeling to demonstrate reduced mass and extended life; (2) thermal conductivity testing of high

  10. Ultra-Lightweight Self-Deployable SMP Nanocomposite Sandwich for Habitat Applications, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Space deployable and rigidizable structures that are ultra-lightweight, and have gas barrier property, space durability, and high impact resistance are desirable to...

  11. Self Deployable Ultra-Lightweight Modular Unit for Habitat Structural Applications, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Space deployable and rigidizable structures which are ultra-lightweight, and have high rigidity, space durability, and high impact resistance are desirable to...

  12. Lightweight Hybrid Ablator Incorporating Aerogel-Filled Open-Cell Foam Structural Insulator, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — In previous work for NASA and DoD, Ultramet developed lightweight open-cell foam insulators composed of a carbon or ceramic structural foam skeleton filled with a...

  13. Ultra-Lightweight High Efficiency Nanostructured Materials and Coatings for Deep Space Mission Environments, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — NanoSonic has developed a nanostructured spray self-assembly manufacturing method that has resulted in ultra-lightweight ( 1000%), and multi-layer, high efficiency...

  14. Innovative, Lightweight Thoraeus RubberTM for MMOD and Space Radiation Shielding, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NanoSonic offers an innovative manufacturing process to yield ultra-lightweight radiation shielding nanocomposites by exploiting the concept of the Thoraeus filter...

  15. Ultra-Lightweight Nanocomposite Foams and Sandwich Structures for Space Structures Applications, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Space structures that are ultra-lightweight, and have gas barrier property, space durability, radiation resistance and high impact resistance are desirable to...

  16. Ultra-Lightweight Nanocomposite Foams and Sandwich Structures for Space Structures Applications, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Space structures that are ultra-lightweight, and have gas barrier property, space durability, radiation resistance, EMI shielding, and high impact resistance are...

  17. Lightweight Metal Rubber Wire and Cable for Space Power Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this NASA STTR program is to produce ultra-lightweight electrical wire and cable harnesses to reduce the liftoff weight of future space flight...

  18. Data Base for Light-Weight Automotive Diesel Power Plants. Volume 2: Discussion and Results.

    Science.gov (United States)

    1979-12-01

    The effects on fuel economy, emissions, passenger car safety and other variables due to the installation of light-weight Diesel powerplants were studied. Experimental data was obtained on naturally aspirated and turbocharged Diesel engines installed ...

  19. Data Base for Light-Weight Automotive Diesel Power Plants: Volume 1. Executive Summary.

    Science.gov (United States)

    1979-12-01

    The effects on fuel economy, emissions, passenger car safety and other variables due to the installation of light-weight Diesel powerplants were studied. Experimental data was obtained on naturally aspirated and turbocharged Diesel engines installed ...

  20. Data Base for Light-Weight Automotive Diesel Power Plants : Volume 3. Miscellaneous Data.

    Science.gov (United States)

    1979-12-01

    The effects of fuel economy, emissions, passenger car safety and other variables due to the installation of light-weight Diesel powerplants were studied. Experimental data was obtained on naturally aspirated and turbocharged Diesel engines installed ...

  1. Ultra-Lightweight, High Efficiency Silicon-Carbide (SIC) Based Power Electronic Converters, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business of Innovation Research Phase I proposal seeks to investigate and prove the feasibility of developing highly efficient, ultra-lightweight SiC...

  2. A New Ultra-lightweight Authentication Protocol for Low Cost RFID Tags

    Directory of Open Access Journals (Sweden)

    Xin Wang

    2013-05-01

    Full Text Available The Radio Frequency Identification (RFID system has been widely used in almost every aspects of the society. At present, the problem of security and privacy become a key factor of severely blocking the widespread of its usage. However, due to restraints on RFID tag’s manufacturing cost, the traditional methods of encryption are not good candidate to defend the security of wireless communication channel between reader and tag. Designing lightweight or ultra-lightweight RFID authentication protocol has become a hot research topic recently. This paper proposes a new ultra-lightweight RFID authentication protocol with high robustness and execution efficiency. The proposed protocol requires only simple bit-wise operations, it has the characteristics of low storage requirement and communication cost. At the same time, through elaborate mechanism design, avoid the vulnerability of the existing ultra-lightweight authentication protocols.

  3. Precision Membrane Optical Shell (PMOS) Technology for Lightweight LIDAR Apertures, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Precision membrane optical shell (PMOS) technology is an innovative combination of 1) ultra lightweight optically smooth membrane thin films, 2) advanced mold based...

  4. Multi-component lightweight gearwheels with deep-drawn wheel body for automotive applications

    Science.gov (United States)

    Benkert, Tim; Hiller, Maria; Volk, Wolfram

    2017-09-01

    Multi-component gearwheels offer great lightweight opportunities for automotive applications. An assembly of a gear ring and a wheel body joined by press fit replaces the monolithic gearwheel. To save weight, the wheel body uses lightweight design. This lightweight design influences the assembled gearwheel’s mechanical properties like stiffness, weight and torque capacity. Further, the wheel body material influences the mentioned properties as well. In this paper, the effects of the lightweight wheel body manufactured by deep-drawing on the mechanical properties of the assembled gearwheel are investigated. Three different wheel body designs are examined regarding their stiffness and weight compared to a reference gearwheel. Using the best design, the influence of five materials with increasing yield strength on the maximum torque the gearwheel can transmit is studied. All research is done virtually using Abaqus 6.12-3.

  5. A Compact, Light-weight, Reliable and Highly Efficient Heat Pump for, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — RTI proposes to develop an efficient, reliable, compact and lightweight heat pump for space applications. The proposed effort is expected to lead to (at the end of...

  6. Development of lightweight concrete mixes for construction industry at the state of Arkansas

    Science.gov (United States)

    Almansouri, Mohammed Abdulwahab

    As the construction industry evolved, the need for more durable, long lasting infrastructure increased. Therefore, more efforts have been put to find new methods to improve the properties of the concrete to prolong the service life of the structural elements. One of these methods is the use of lightweight aggregate as an internal curing agent to help reducing self-desiccation and shrinkage. This research studied the effects of using locally available lightweight aggregate (expanded clay), as a partial replacement of normal weight aggregate in the concrete matrix. The concrete mixtures contained lightweight aggregate with a replacement percentage of 12.5, 25, 37.5, and 50 percent by volume. Fresh properties as well as compressive strength, modulus of rupture, and drying shrinkage were measured. While was effective in reducing drying shrinkage, the use of lightweight aggregate resulted in slightly reducing both the compressive strength and modulus of rupture.

  7. Lightweight Design of an HTS Coil for the VASIMR Experiment, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — In this Phase II SBIR contract Tai-Yang Research Company of Tennessee proposes to design, fabricate, and test an ultra-lightweight High Temperature Superconducting...

  8. High Efficiency Advanced Lightweight Fuel Cell (HEAL-FC), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Infinity's High Efficiency Advanced Lightweight Fuel Cell (HEAL FC) is an improved version of its current fuel cell technology developed for space applications. The...

  9. Lightweight Ultrahigh Temperature CMC-Lined C/C Combustion Chambers, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA and DoD are seeking high-performance, lightweight liquid rocket combustion chambers with future performance goals that cannot be achieved using state-of-the-art...

  10. Lightweight Tactical Client: A Capability-Based Approach to Command Post Computing

    Science.gov (United States)

    2015-12-01

    bundles these capabilities together is proposed: a lightweight tactical client. In order to avoid miscommunication in the future, it is... solutions and almost definitely rules out most terminal-based thin clients. UNCLASSIFIED Approved for public release

  11. Lightweight and Compace Multifunction Computer-Controlled Strength and Aerobic Training Device, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — TDA Research proposes to develop a computer-controlled lightweight and compact device for aerobic and resistive training (DART) to counteract muscular atrophy and...

  12. Human Factors Evaluation of the Modular Lightweight Load-Carrying Equipment (MOLLE) System

    National Research Council Canada - National Science Library

    Sampson, James

    2001-01-01

    .... The FEA was used in drafting a new user requirements document and initiating the development of a modular load-carrying system which ultimately became known as the Modular Lightweight Load-carrying Equipment (MOLLE...

  13. Silicon Carbide Lightweight Optics With Hybrid Skins for Large Cryo Telescopes, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Optical Physics Company (OPC) has developed new silicon carbide (SiC) foam-based optics with hybrid skins that are composite, athermal and lightweight (FOCAL) that...

  14. Transgenerational plasticity is adaptive in the wild.

    Science.gov (United States)

    Galloway, Laura F; Etterson, Julie R

    2007-11-16

    Plants exhibit adaptive responses to light, but it is not known whether parental plants transmit environmental cues that elicit adaptive responses in offspring. We show that offspring life history (annual versus biennial) is influenced by the maternal light environment (understory versus light gap). This transgenerational plasticity is adaptive when offspring are grown in their maternal light environment, where seeds typically disperse. Projections of population growth show that plants that are appropriately cued for their light environment through maternal effects have 3.4 times greater fitness than otherwise. Transgenerational plasticity has evolved in response to natural variation in light and provides a flexible mechanism by which sedentary organisms cope with heterogeneous environments.

  15. The neurophysiologist perspective into MS plasticity

    Directory of Open Access Journals (Sweden)

    Elise eHoudayer

    2015-09-01

    Full Text Available Multiple sclerosis (MS is a frequent, highly debilitating inflammatory demyelinating disease, starting to manifest in early adulthood and presenting a wide variety of symptoms which are often resistant to pharmacological treatments. Cortical dysfunctions have been demonstrated to be key components of MS condition, and plasticity of the corticospinal motor system is highly involved in major MS symptoms, such as fatigue, spasticity or pain. Cortical dysfunction in MS can be studied with neurophysiological tools such as electroencephalography (EEG and related techniques (evoked potentials – EPs or transcranial magnetic stimulation (TMS. These techniques are now widely used to provide essential elements of MS diagnosis and can also be used to modulate plasticity. Indeed the recent development of non-invasive brain stimulation (NIBS techniques able to induce cortical plasticity, such as repetitive TMS or transcranial direct current stimulation (tDCS, has brought promising results as add-on treatments.In this review we will focus on the use of these tools (EEG, TMS to study plasticity in MS and on the major techniques used to modulate plasticity in MS.

  16. The Neurophysiologist Perspective into MS Plasticity.

    Science.gov (United States)

    Houdayer, Elise; Comi, Giancarlo; Leocani, Letizia

    2015-01-01

    Multiple sclerosis (MS) is a frequent, highly debilitating inflammatory demyelinating disease, starting to manifest in early adulthood and presenting a wide variety of symptoms, which are often resistant to pharmacological treatments. Cortical dysfunctions have been demonstrated to be key components of MS condition, and plasticity of the corticospinal motor system is highly involved in major MS symptoms, such as fatigue, spasticity, or pain. Cortical dysfunction in MS can be studied with neurophysiological tools, such as electroencephalography (EEG) and related techniques (evoked potentials) or transcranial magnetic stimulation (TMS). These techniques are now widely used to provide essential elements of MS diagnosis and can also be used to modulate plasticity. Indeed, the recent development of non-invasive brain stimulation techniques able to induce cortical plasticity, such as repetitive TMS or transcranial direct current stimulation, has brought promising results as add-on treatments. In this review, we will focus on the use of these tools (EEG and TMS) to study plasticity in MS and on the major techniques used to modulate plasticity in MS.

  17. Sub-nanosecond plastic scintillators

    International Nuclear Information System (INIS)

    Lyons, P.B.; Caldwell, S.E.; Hocker, L.P.; Crandall, D.G.; Zagarino, P.A.; Cheng, J.; Tirsell, G.; Hurlbut, C.R.

    1977-01-01

    Quenched plastic scintillators have been developed that yield much faster short decay components and greatly reduced long decay components compared to conventional plastic scintillators. The plastics are produced through the addition of selected quench agents to NE111 plastic scintillator that result in reduced total light output. Eight different agents have been studied. Benzophenone and piperidine are two of the most effective quench agents. Data are presented both for short and long decay components. The plastics are expected to make significant contributions in areas of plasma diagnostics

  18. Sub-nanosecond plastic scintillators

    International Nuclear Information System (INIS)

    Lyons, P.B.; Caldwell, S.E.; Hocker, L.P.; Crandall, D.G.; Zagarino, P.A.; Cheng, J.; Tirsell, G.; Hurlbut, C.R.

    1976-01-01

    Quenched plastic scintillators have been developed that yield much faster short decay components and greatly reduced long decay components compared to conventional plastic scintillators. The plastics are produced through the addition of selected quench agents to NE111 plastic scintillator that result in reduced total light output. Eight different agents have been studied. Benzophenone and piperidine are two of the most effective quench agents. Data are presented both for short and long decay components. The plastics are expected to make significant contributions in areas of plasma diagnostics

  19. Efficient and anonymous two-factor user authentication in wireless sensor networks: achieving user anonymity with lightweight sensor computation.

    Science.gov (United States)

    Nam, Junghyun; Choo, Kim-Kwang Raymond; Han, Sangchul; Kim, Moonseong; Paik, Juryon; Won, Dongho

    2015-01-01

    A smart-card-based user authentication scheme for wireless sensor networks (hereafter referred to as a SCA-WSN scheme) is designed to ensure that only users who possess both a smart card and the corresponding password are allowed to gain access to sensor data and their transmissions. Despite many research efforts in recent years, it remains a challenging task to design an efficient SCA-WSN scheme that achieves user anonymity. The majority of published SCA-WSN schemes use only lightweight cryptographic techniques (rather than public-key cryptographic techniques) for the sake of efficiency, and have been demonstrated to suffer from the inability to provide user anonymity. Some schemes employ elliptic curve cryptography for better security but require sensors with strict resource constraints to perform computationally expensive scalar-point multiplications; despite the increased computational requirements, these schemes do not provide user anonymity. In this paper, we present a new SCA-WSN scheme that not only achieves user anonymity but also is efficient in terms of the computation loads for sensors. Our scheme employs elliptic curve cryptography but restricts its use only to anonymous user-to-gateway authentication, thereby allowing sensors to perform only lightweight cryptographic operations. Our scheme also enjoys provable security in a formal model extended from the widely accepted Bellare-Pointcheval-Rogaway (2000) model to capture the user anonymity property and various SCA-WSN specific attacks (e.g., stolen smart card attacks, node capture attacks, privileged insider attacks, and stolen verifier attacks).

  20. Circuit design on plastic foils

    CERN Document Server

    Raiteri, Daniele; Roermund, Arthur H M

    2015-01-01

    This book illustrates a variety of circuit designs on plastic foils and provides all the information needed to undertake successful designs in large-area electronics.  The authors demonstrate architectural, circuit, layout, and device solutions and explain the reasons and the creative process behind each. Readers will learn how to keep under control large-area technologies and achieve robust, reliable circuit designs that can face the challenges imposed by low-cost low-temperature high-throughput manufacturing.   • Discusses implications of problems associated with large-area electronics and compares them to standard silicon; • Provides the basis for understanding physics and modeling of disordered material; • Includes guidelines to quickly setup the basic CAD tools enabling efficient and reliable designs; • Illustrates practical solutions to cope with hard/soft faults, variability, mismatch, aging and bias stress at architecture, circuit, layout, and device levels.