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Sample records for stripper harvested high

  1. Picker versus stripper harvesters on the High Plains of Texas

    Science.gov (United States)

    A break even analysis based on NPV was conducted to compare picker-based and stripper-based harvest systems with and without field cleaners. Under no conditions analyzed was the NPV of a stripper system without a field cleaner greater than a stripper system with a field cleaner. Break even curves re...

  2. Comparison of a wire belt conveyor and cross auger conveyor for conveying burr cotton on a stripper harvester

    Science.gov (United States)

    Cotton fiber quality begins to degrade naturally with the opening of the boll, and mechanical harvesting processes are perceived to exacerbate fiber degradation. Previous research indicates that stripper-harvested cotton generally has lower fiber quality including on average lower micronaire, length...

  3. Waste rice seed in conventional and stripper-head harvested fields in California: Implications for wintering waterfowl

    Science.gov (United States)

    Fleskes, Joseph P.; Halstead, Brian J.; Casazza, Michael L.; Coates, Peter S.; Kohl, Jeffrey D.; Skalos, Daniel A.

    2012-01-01

    Waste rice seed is an important food for wintering waterfowl and current estimates of its availability are needed to determine the carrying capacity of rice fields and guide habitat conservation. We used a line-intercept method to estimate mass-density of rice seed remaining after harvest during 2010 in the Sacramento Valley (SACV) of California and compared results with estimates from previous studies in the SACV and Mississippi Alluvial Valley (MAV). Posterior mean (95% credible interval) estimates of total waste rice seed mass-density for the SACV in 2010 were 388 (336–449) kg/ha in conventionally harvested fields and 245 (198–307) kg/ha in stripper-head harvested fields; the 2010 mass-density is nearly identical to the mid-1980s estimate for conventionally harvested fields but 36% lower than the mid-1990s estimate for stripped fields. About 18% of SACV fields were stripper-head harvested in 2010 vs. 9–15% in the mid-1990s and 0% in the mid-1980s; but due to a 50% increase in planted rice area, total mass of waste rice seed in SACV remaining after harvest in 2010 was 43% greater than in the mid-1980s. However, total mass of seed-eating waterfowl also increased 82%, and the ratio of waste rice seed to seed-eating waterfowl mass was 21% smaller in 2010 than in the mid-1980s. Mass-densities of waste rice remaining after harvest in SACV fields are within the range reported for MAV fields. However, because there is a lag between harvest and waterfowl use in the MAV but not in the SACV, seed loss is greater in the MAV and estimated waste seed mass-density available to wintering waterfowl in SACV fields is about 5–30 times recent MAV estimates. Waste rice seed remains an abundant food source for waterfowl wintering in the SACV, but increased use of stripper-head harvesters would reduce this food. To provide accurate data on carrying capacities of rice fields necessary for conservation planning, trends in planted rice area, harvest method, and postharvest field

  4. Liquid-film stripper for high-intensity heavy-ion beams

    International Nuclear Information System (INIS)

    Leemann, B.T.; Merrill, P.; Syversrud, H.K.; Wada, R.; Yourd, R.B.

    1981-03-01

    Electron strippers are widely used in heavy ion accelerators such as tandem Van de Graaff generators and heavy ion linacs. The SuperHILAC at Lawrence Berkeley Laboratory, employs a fluorocarbon oil vapor stripper at 113 keV/A for its high intensity injector ABEL, while after acceleration to 1.199 MeV/A a 35 μg/cm 2 carbon foil stripper is used. At present, the lifetime of these foils is about 1 hour for an 40 Ar beam of approx. 1 μA average particle current. With higher intensity high mass (100 less than or equal to A less than or equal to 238) beams available from ABEL injector the lifetime is expected to drop drastically and might be as low as one minute. A different approach to solve the stripper foil lifetime problem uses a thin free standing oil film spun from the edge of a sharp-edged rotating disc touching the surface of an oil reservoir. Areas of about 10 cm 2 with areal densities down to 20 μg/cm 2 have been reported. The work described here is based on the same concept, and produces a constantly regenerated, stable, free standing oil film of appropriate thickness for use at the SuperHILAC

  5. All fiber cladding mode stripper with uniform heat distribution and high cladding light loss manufactured by CO2 laser ablation

    Science.gov (United States)

    Jebali, M. A.; Basso, E. T.

    2018-02-01

    Cladding mode strippers are primarily used at the end of a fiber laser cavity to remove high-power excess cladding light without inducing core loss and beam quality degradation. Conventional manufacturing methods of cladding mode strippers include acid etching, abrasive blasting or laser ablation. Manufacturing of cladding mode strippers using laser ablation consist of removing parts of the cladding by fused silica ablation with a controlled penetration and shape. We present and characterize an optimized cladding mode stripper design that increases the cladding light loss with a minimal device length and manufacturing time. This design reduces the localized heat generation by improving the heat distribution along the device. We demonstrate a cladding mode stripper written on a 400um fiber with cladding light loss of 20dB, with less than 0.02dB loss in the core and minimal heating of the fiber and coating. The manufacturing process of the designed component is fully automated and takes less than 3 minutes with a very high throughput yield.

  6. Robust cladding light stripper for high-power fiber lasers using soft metals.

    Science.gov (United States)

    Babazadeh, Amin; Nasirabad, Reza Rezaei; Norouzey, Ahmad; Hejaz, Kamran; Poozesh, Reza; Heidariazar, Amir; Golshan, Ali Hamedani; Roohforouz, Ali; Jafari, S Naser Tabatabaei; Lafouti, Majid

    2014-04-20

    In this paper we present a novel method to reliably strip the unwanted cladding light in high-power fiber lasers. Soft metals are utilized to fabricate a high-power cladding light stripper (CLS). The capability of indium (In), aluminum (Al), tin (Sn), and gold (Au) in extracting unwanted cladding light is examined. The experiments show that these metals have the right features for stripping the unwanted light out of the cladding. We also find that the metal-cladding contact area is of great importance because it determines the attenuation and the thermal load on the CLS. These metals are examined in different forms to optimize the contact area to have the highest possible attenuation and avoid localized heating. The results show that sheets of indium are very effective in stripping unwanted cladding light.

  7. Kilowatt-level cladding light stripper for high-power fiber laser.

    Science.gov (United States)

    Yan, Ping; Sun, Junyi; Huang, Yusheng; Li, Dan; Wang, Xuejiao; Xiao, Qirong; Gong, Mali

    2017-03-01

    We designed and fabricated a high-power cladding light stripper (CLS) by combining a fiber-etched CLS with a cascaded polymer-recoated CLS. The etched fiber reorganizes the numerical aperture (NA) distribution of the cladding light, leading to an increase in the leakage power and a flatter distribution of the leakage proportion in the cascaded polymer-recoated fiber. The index distribution of the cascaded polymer-recoated fiber is carefully designed to ensure an even leakage of cladding light. More stages near the index of 1.451 are included to disperse the heat. The CLS is capable of working consistently under 1187 W of cladding light with an attenuation of 26.59 dB, and the highest local temperature is less than 35°C.

  8. Development of stripper films made of high strength, long life carbon nitride

    International Nuclear Information System (INIS)

    Oyaizu, Mitsuhiro; Sugai, Isamu; Yoshida, Koji; Haruyama, Yoichi.

    1994-01-01

    The heavy ion accelerators such as tandem type van de Graaff, linear accelerators, cyclotrons and so on raise the acceleration efficiency usually by producing multivalent ions by making the charge conversion of heavy ions using carbon thin films. However, when the electrons of large atomic number ions of low energy, high intensity current are stripped, the conventional carbon thin films on the market or home made were very short in their life, and have become the cause of remarkably lowering the acceleration efficiency. The concrete objectives of the development are the use of the charge conversion of unstable nuclear ions in the E arena accelerator for JHP of the future project of Institute of Nuclear Study and the manufacture of the carbon films which are used for the charge conversion of the H beam of high energy, but at the time of exchanging the films, there is the problem of the radiation exposure of large amount, therefore, the development of high reliability, long life stripper films has been strongly demanded. The experiment was carried out by controlled carbon arc discharge process using both AC and DC and the ion beam sputtering process using reactive nitrogen gas. The results are reported. (K.I.)

  9. CO2 laser-fabricated cladding light strippers for high-power fiber lasers and amplifiers.

    Science.gov (United States)

    Boyd, Keiron; Simakov, Nikita; Hemming, Alexander; Daniel, Jae; Swain, Robert; Mies, Eric; Rees, Simon; Andrew Clarkson, W; Haub, John

    2016-04-10

    We present and characterize a simple CO2 laser processing technique for the fabrication of compact all-glass optical fiber cladding light strippers. We investigate the cladding light loss as a function of radiation angle of incidence and demonstrate devices in a 400 μm diameter fiber with cladding losses of greater than 20 dB for a 7 cm device length. The core losses are also measured giving a loss of cladding light stripping of a 300 W laser diode with minimal heating of the fiber coating and packaging adhesives.

  10. A new gas stripper system for BARC-TIFR Pelletron Accelerator facility: installation and preliminary results

    International Nuclear Information System (INIS)

    Sharma, S.C.; Ninawe, N.G.; Yadav, M.L.; Ekambaram, M.; Ramjilal; Matkar, U.V.; Ansari, Q.N.; Lokare, R.N.; Ramlal; Gupta, A.K.; Bhagwat, P.V.; Pillay, R.G.

    2009-01-01

    The gas-stripper plays a key role in stripping the heavy and molecular ion beams in a tandem accelerator. Efficiency of gas stripper depends on its supporting vacuum pumps. A new recirculating turbo molecular pump-based gas stripper has been installed in the high voltage terminal of Pelletron Accelerator. Re-circulating the stripper gas reduces the flow of gas into the accelerating tubes reducing the transmission losses. Preliminary results obtained using the new gas stripper system are discussed. (author)

  11. Heat suppression of the fiber coating on a cladding light stripper in high-power fiber laser.

    Science.gov (United States)

    Yan, Ming-Jian; Wang, Zheng; Meng, Ling-Qiang; Yin, Lu; Han, Zhi-Gang; Shen, Hua; Wang, Hai-Lin; Zhu, Ri-Hong

    2018-01-20

    We present a theoretical model for the thermal effect of the fiber coating on a high-power cladding light stripper, which is fabricated by chemical etching. For the input and output of the fiber coating, a novel segmented corrosion method and increasing attenuation method are proposed for heat suppression, respectively. The relationship between the attenuation and temperature rise of the fiber coating at the output is experimentally demonstrated. The temperature distribution of the fiber coating at the input as well as the return light power caused by scattering are measured for the etched fiber with different surface roughness values. The results suggest that the rise in temperature is primarily caused by the scattering light propagating into the coating. Finally, an attenuation of 27 dB is achieved. At a room temperature of 23°C and input pump power of 438 W, the highest temperature of the input fiber coating decreases from 39.5°C to 27.9°C by segmented corrosion, and the temperature rise of the output fiber coating is close to 0.

  12. Development of a rotating graphite carbon disk stripper

    Science.gov (United States)

    Hasebe, Hiroo; Okuno, Hiroki; Tatami, Atsushi; Tachibana, Masamitsu; Murakami, Mutsuaki; Kuboki, Hironori; Imao, Hiroshi; Fukunishi, Nobuhisa; Kase, Masayuki; Kamigaito, Osamu

    2018-05-01

    Highly oriented graphite carbon sheets (GCSs) were successfully used as disk strippers. An irradiation test conducted in 2015 showed that GCS strippers have the longest lifetime and exhibit improved stripping and transmission efficiencies. The problem of disk deformation in previously used Be-disk was solved even with higher beam intensity.

  13. Development of stripper options for FRIB

    Energy Technology Data Exchange (ETDEWEB)

    Marti, F.; Hershcovitch, A.; Momozaki, Y.; Nolen, J.; Reed, C.; Thieberger, P.

    2010-09-12

    The US Department of Energy Facility for Rare Isotope Beams (FRIB) at Michigan State University includes a heavy ion superconducting linac capable of accelerating all ions up to uranium with energies higher than 200 MeV/u and beam power up to 400 kW. To achieve these goals with present ion source performance it is necessary to accelerate simultaneously two charge states of uranium from the ion source in the first section of the linac. At an energy of approximately 16.5 MeV/u it is planned to strip the uranium beam to reduce the voltage needed in the rest of the linac to achieve the final energy. Up to five different charge states are planned to be accelerated simultaneously after the stripper. The design of the stripper is a challenging problem due to the high power deposited (approximately 0.7 kW) in the stripper media by the beam in a small spot. To assure success of the project we have established a research and development program that includes several options: carbon or diamond foils, liquid lithium films, gas strippers and plasma strippers. We present in this paper the status of the different options.

  14. P-type diamond stripper foils for tandem ion accelerators

    International Nuclear Information System (INIS)

    Phelps, A.W.; Koba, R.

    1989-01-01

    The authors are developing a stripper foil composed of a p-type diamond membrane. This diamond stripper foil should have a significantly longer lifetime than any conventional stripper foil material. To be useful for stripper foils, the boron-doped blue diamond films must be thinner than 0.8 μm and pore-free. Two methods are compared for their ability to achieve a high nucleation areal density on a W substrate. Some W substrates were first coated with think layer of boron (≤20 nm) in order to enhance nucleation. Other W substrates were scratched with submicron diamond particles. A schematic diagram of the stripper foil is shown. Stripper foils were created by etching away the central area of W substrates. The diamond membrane was then supported by an annulus of W. Tungsten was selected as a ring-support material because of its high electrical and thermal conductivity, relatively low thermal expansion, and proven suitability as a substrate for diamond CVD. Warping or fracture of the diamond film after substrate etch-back was investigated

  15. Simulation of ion beam scattering in a gas stripper

    Energy Technology Data Exchange (ETDEWEB)

    Maxeiner, Sascha, E-mail: maxeiner@phys.ethz.ch; Suter, Martin; Christl, Marcus; Synal, Hans-Arno

    2015-10-15

    Ion beam scattering in the gas stripper of an accelerator mass spectrometer (AMS) enlarges the beam phase space and broadens its energy distribution. As the size of the injected beam depends on the acceleration voltage through phase space compression, the stripper becomes a limiting factor of the overall system transmission especially for low energy AMS system in the sub MV region. The spatial beam broadening and collisions with the accelerator tube walls are a possible source for machine background and energy loss fluctuations influence the mass resolution and thus isotope separation. To investigate the physical processes responsible for these effects, a computer simulation approach was chosen. Monte Carlo simulation methods are applied to simulate elastic two body scattering processes in screened Coulomb potentials in a (gas) stripper and formulas are derived to correctly determine random collision parameters and free path lengths for arbitrary (and non-homogeneous) gas densities. A simple parametric form for the underlying scattering cross sections is discussed which features important scaling behaviors. An implementation of the simulation was able to correctly model the data gained with the TANDY AMS system at ETH Zurich. The experiment covered transmission measurements of uranium ions in helium and beam profile measurements after the ion beam passed through the He-stripper. Beam profiles measured up to very high stripper densities could be understood in full system simulations including the relevant ion optics. The presented model therefore simulates the fundamental physics of the interaction between an ion beam and a gas stripper reliably. It provides a powerful and flexible tool for optimizing existing AMS stripper geometries and for designing new, state of the art low energy AMS systems.

  16. Energy harvesting in high voltage measuring techniques

    International Nuclear Information System (INIS)

    Żyłka, Pawel; Doliński, Marcin

    2016-01-01

    The paper discusses selected problems related to application of energy harvesting (that is, generating electricity from surplus energy present in the environment) to supply autonomous ultra-low-power measurement systems applicable in high voltage engineering. As a practical example of such implementation a laboratory model of a remote temperature sensor is presented, which is self-powered by heat generated in a current-carrying busbar in HV- switchgear. Presented system exploits a thermoelectric harvester based on a passively cooled Peltier module supplying micro-power low-voltage dc-dc converter driving energy-efficient temperature sensor, microcontroller and a fibre-optic transmitter. Performance of the model in laboratory simulated conditions are presented and discussed. (paper)

  17. Energy harvesting from high-rise buildings by a piezoelectric harvester device

    International Nuclear Information System (INIS)

    Xie, X.D.; Wang, Q.; Wang, S.J.

    2015-01-01

    A novel piezoelectric technology of harvesting energy from high-rise buildings is developed. While being used to harness vibration energy of a building, the technology is also helpful to dissipate vibration of the building by the designed piezoelectric harvester as a tuned mass damper. The piezoelectric harvester device is made of two groups of series piezoelectric generators connected by a shared shaft. The shaft is driven by a linking rod hinged on a proof mass on the tip of a cantilever fixed on the roof of the building. The influences of some practical considerations, such as the mass ratio of the proof mass to the main structure, the ratios of the length and flexural rigidity of the cantilever to those of the main structure, on the root mean square (RMS) of the generated electric power and the energy harvesting efficiency of the piezoelectric harvester device are discussed. The research provides a new method for an efficient and practical energy harvesting from high-rise buildings by piezoelectric harvesters. - Highlights: • A new piezoelectric technology in energy harvesting from high-rise buildings is introduced. • A new mathematics model to calculate the energy harvested by the piezoelectric device is developed. • A novel efficient design of the piezoelectric harvester device in provided. • An electric power up to 432 MW under a seismic excitation at a frequency of 30 rad/s is achieved.

  18. Fabrication of versatile cladding light strippers and fiber end-caps with CO2 laser radiation

    Science.gov (United States)

    Steinke, M.; Theeg, T.; Wysmolek, M.; Ottenhues, C.; Pulzer, T.; Neumann, J.; Kracht, D.

    2018-02-01

    We report on novel fabrication schemes of versatile cladding light strippers and end-caps via CO2 laser radiation. We integrated cladding light strippers in SMA-like connectors for reliable and stable fiber-coupling of high-power laser diodes. Moreover, the application of cladding light strippers in typical fiber geometries for high-power fiber lasers was evaluated. In addition, we also developed processes to fuse end-caps to fiber end faces via CO2 laser radiation and inscribe the fibers with cladding light strippers near the end-cap. Corresponding results indicate the great potential of such devices as a monolithic and low-cost alternative to SMA connectors.

  19. High School Harvest: Combining Food Service Training and Institutional Procurement

    Science.gov (United States)

    Conner, David; Estrin, Hans; Becot, Florence

    2014-01-01

    This article discusses High School Harvest (HSH), an Extension educator-led project in five Vermont schools to provide students with job training and food system education and to provide lightly processed produce to school lunch programs. One hundred and twenty-one students participated, logging 8,752 hours growing, harvesting, and processing…

  20. High relative humidity pre-harvest reduces post-harvest proliferation of Salmonella in tomatoes.

    Science.gov (United States)

    Devleesschauwer, Brecht; Marvasi, Massimiliano; Giurcanu, Mihai C; Hochmuth, George J; Speybroeck, Niko; Havelaar, Arie H; Teplitski, Max

    2017-09-01

    Outbreaks of human illness caused by enteric pathogens such as Salmonella are increasingly linked to the consumption of fruits and vegetables. Knowledge on the factors affecting Salmonella proliferation on fresh produce therefore becomes increasingly important to safeguard public health. Previous experiments showed a limited impact of pre-harvest production practices on Salmonella proliferation on tomatoes, but suggested a significant effect of harvest time. We explored the data from two previously published and one unpublished experiment using regression trees, which allowed overcoming the interpretational difficulties of classical statistical models with higher order interactions. We assessed the effect of harvest time by explicitly modeling the climatic conditions at harvest time and by performing confirmatory laboratory experiments. Across all datasets, regression trees confirmed the dominant effect of harvest time on Salmonella proliferation, with humidity-related factors emerging as the most important underlying climatic factors. High relative humidity the week prior to harvest was consistently associated with lower Salmonella proliferation. A controlled lab experiment confirmed that tomatoes containing their native epimicrobiota supported significantly lower Salmonella proliferation when incubated at higher humidity prior to inoculation. The complex interactions between environmental conditions and the native microbiota of the tomato crop remain to be fully understood. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. High-efficiency integrated piezoelectric energy harvesting systems

    Science.gov (United States)

    Hande, Abhiman; Shah, Pradeep

    2010-04-01

    This paper describes hierarchically architectured development of an energy harvesting (EH) system that consists of micro and/or macro-scale harvesters matched to multiple components of remote wireless sensor and communication nodes. The micro-scale harvesters consist of thin-film MEMS piezoelectric cantilever arrays and power generation modules in IC-like form to allow efficient EH from vibrations. The design uses new high conversion efficiency thin-film processes combined with novel cantilever structures tuned to multiple resonant frequencies as broadband arrays. The macro-scale harvesters are used to power the collector nodes that have higher power specifications. These bulk harvesters can be integrated with efficient adaptive power management circuits that match transducer impedance and maximize power harvested from multiple scavenging sources with very low intrinsic power consumption. Texas MicroPower, Inc. is developing process based on a composition that has the highest reported energy density as compared to other commercially available bulk PZT-based sensor/actuator ceramic materials and extending it to thin-film materials and miniature conversion transducer structures. The multiform factor harvesters can be deployed for several military and commercial applications such as underground unattended sensors, sensors in oil rigs, structural health monitoring, supply chain management, and battlefield applications such as sensors on soldier apparel, equipment, and wearable electronics.

  2. Production of thin carbon stripper foils using heated-substrates in a cathodic arc deposition system

    International Nuclear Information System (INIS)

    Merchant, A.R.; Lobanov, N.; Elliman, R.G.; Ophel, T.R.; Rode, A.; Weisser, D.C.; Turkentine, R.B.

    1998-01-01

    The lifetime of carbon stripper foil can have a marked impact on the successful running of a beam line. Standard techniques for production of carbon stripper foils include evaporation of carbon (ec) and laser-pulsed ablation (Ipa). Recent work by a using Ipa has been successful in substantially increasing the lifetime of a very thin foil. The suspected mechanism for the increased lifetime of the foil is that the amorphous carbon foil is density-matched to that of graphite (around 2.26g/cc). In this work, we attempt to reproduce this result by producing carbon stripper foils with a mass-density similar to graphite using a cathodic arc deposition system. The cathodic arc is well known for the production of tetrahedral amorphous carbon: a high density, high stress form of carbon with over 90% sp 3 -like bonds; to reduce the density of the carbon and promote more graphitic structure, a high bias was initially attempted but this proved unsuccessful. Another method is to use a heated-substrate holder to reduce compressive stress within the deposited film. The performance of the density-matched carbon stripper foils and the implications for future production of high-quality carbon stripper foils in our laboratory will be discussed. (authors)

  3. Effect of thickness of foil strippers in transmission of beams through 15 UD pelletron accelerator at IUAC

    International Nuclear Information System (INIS)

    Ojha, S.; Pankaj Kumar; Gargari, S.; Joshi, R.; Abhilash; Kabiraj, D.; Chopra, S.

    2009-01-01

    15 UD Pelletron accelerator at IUAC, New Delhi is equipped with a foil stripper and a gas stripper at high voltage terminal. Besides these, we have foil stripper assemblies at High Energy Dead Section (HEDS) of Pelletron and after analyser magnet. Incoming negative ion looses electrons when they pass through the strippers at terminal and becomes positively charged. The next foil stripper at HEDS increases the positive charge state of ion by removing more electrons which helps in delivering beams at higher energy. Typical thickness of carbon foils loaded in the foil stripper assembly in the terminal is around 4 microgram per square centimetre (4 μg/cm 2 ). Thicker foils were installed in the terminal assembly to study the effect of thickness of foil on charge state distribution and transmission of ion beams. Charge state distribution of ions produced out of molecular beam was also studied. In this paper we present and discuss the results and observations with thicker foils on ion as well as molecular beams. (author)

  4. A metamaterial electromagnetic energy rectifying surface with high harvesting efficiency

    Directory of Open Access Journals (Sweden)

    Xin Duan

    2016-12-01

    Full Text Available A novel metamaterial rectifying surface (MRS for electromagnetic energy capture and rectification with high harvesting efficiency is presented. It is fabricated on a three-layer printed circuit board, which comprises an array of periodic metamaterial particles in the shape of mirrored split rings, a metal ground, and integrated rectifiers employing Schottky diodes. Perfect impedance matching is engineered at two interfaces, i.e. one between free space and the surface, and the other between the metamaterial particles and the rectifiers, which are connected through optimally positioned vias. Therefore, the incident electromagnetic power is captured with almost no reflection by the metamaterial particles, then channeled maximally to the rectifiers, and finally converted to direct current efficiently. Moreover, the rectifiers are behind the metal ground, avoiding the disturbance of high power incident electromagnetic waves. Such a MRS working at 2.45 GHz is designed, manufactured and measured, achieving a harvesting efficiency up to 66.9% under an incident power density of 5 mW/cm2, compared with a simulated efficiency of 72.9%. This high harvesting efficiency makes the proposed MRS an effective receiving device in practical microwave power transmission applications.

  5. A metamaterial electromagnetic energy rectifying surface with high harvesting efficiency

    Science.gov (United States)

    Duan, Xin; Chen, Xing; Zhou, Lin

    2016-12-01

    A novel metamaterial rectifying surface (MRS) for electromagnetic energy capture and rectification with high harvesting efficiency is presented. It is fabricated on a three-layer printed circuit board, which comprises an array of periodic metamaterial particles in the shape of mirrored split rings, a metal ground, and integrated rectifiers employing Schottky diodes. Perfect impedance matching is engineered at two interfaces, i.e. one between free space and the surface, and the other between the metamaterial particles and the rectifiers, which are connected through optimally positioned vias. Therefore, the incident electromagnetic power is captured with almost no reflection by the metamaterial particles, then channeled maximally to the rectifiers, and finally converted to direct current efficiently. Moreover, the rectifiers are behind the metal ground, avoiding the disturbance of high power incident electromagnetic waves. Such a MRS working at 2.45 GHz is designed, manufactured and measured, achieving a harvesting efficiency up to 66.9% under an incident power density of 5 mW/cm2, compared with a simulated efficiency of 72.9%. This high harvesting efficiency makes the proposed MRS an effective receiving device in practical microwave power transmission applications.

  6. Conceptual design of a chickpea harvesting header

    Directory of Open Access Journals (Sweden)

    H. Golpira

    2013-07-01

    Full Text Available Interest in the development of stripper headers is growing owing to the excessive losses of combine harvesters and costs of manually harvesting for chickpeas. The design of a new concept can enhance the mechanized process for chickpea harvesting. A modified stripper platform was designed, in which passive fingers with V-shape slots removes the pods from the anchored plant. The floating platform was accompanied by a reel to complete the harvesting header. Black-box modeling was used to redesign the functional operators of the header followed by an investigation of the system behavior. Physical models of the platform and reel were modified to determine the crucial variables of the header arrangement during field trials. The slot width was fixed at 40 mm, finger length at 40 mm, keyhole diameter at 10 mm and entrance width at 6 mm; the batted reel at peripheral diameter of 700 mm and speed at 50 rpm. A tractor-mounted experimental harvester was built to evaluate the work quality of the stripper header. The performance of the prototype was tested with respect to losses and results confirmed the efficiency of the modified stripper header for chickpea harvesting. Furthermore, the header with a 1.4 m working width produced the spot work rates of 0.42 ha h-1.

  7. Simulation studies of gas and plasma-based charge strippers

    Energy Technology Data Exchange (ETDEWEB)

    Haas, Oliver Sebastian [Institut fuer Theorie Elektromagnetischer Felder, Technische Univ. Darmstadt (Germany); Boine-Frankenheim, Oliver [Institut fuer Theorie Elektromagnetischer Felder, Technische Univ. Darmstadt (Germany); GSI Helmholtz Centre for Heavy Ion Research, Darmstadt (Germany)

    2016-07-01

    Charge stripping of heavy ion beams at high intensities is a major challenge in current and future facilities with high intensity heavy ion beams. Conventional stripping techniques are limited in their applicability, e.g. solid carbon foils suffer from short lifetimes at high intensities and gas strippers usually achieve only low charge states. One possible alternative is the use of a plasma as a stripping medium. The presented work focuses on theoretical studies of the interaction of an heavy ion beam with a plasma and accompanying effects in possible charge strippers. The main interest in the presented studies is the final charge state distribution of the ion beam. Different models for solving the corresponding rate equations were developed, taking into account ionization, recombination, energy loss and straggling processes. Sophisticated models, e.g. for ionization cross sections, as well as limits and applicability of simplified models are discussed. Quantitative results are presented in form an overview of the charge state distributions of different - conventional and novel - charge stripping media. Furthermore comparisons are done with charge state distributions of available experimental data. Typical practically relevant target conditions are discussed as well as deterioration of beam quality.

  8. NONPROCESS SOLVENT USE IN THE FURNITURE REFINISHING AND REPAIR INDUSTRY: EVALUATION OF ALTERNATIVE CHEMICAL STRIPPERS

    Science.gov (United States)

    The report gives results of an evaluation of the feasibility of using alternatives to high volatile organic compound/hazardous air pollutant (VOC/HAP) solvent-based, chemical strippers that are currently used in the furniture repair and refinishing industry to remove both traditi...

  9. ADVANCED TECHNOLOGIES FOR STRIPPER GAS WELL ENHANCEMENT

    International Nuclear Information System (INIS)

    Charles M. Boyer II; Ronald J. MacDonald P.G.

    2001-01-01

    As part of Task 1 in Advanced Technologies for Stripper Gas Well Enhancement, Schlumberger-Holditch Reservoir Technologies (H-RT) has joined with two Appalachian Basin producers, Great Lakes Energy Partners, LLC, and Belden and Blake Corporation to develop methodologies for identification and enhancement of stripper wells with economic upside potential. These industry partners have provided us with data for more than 700 wells in northwestern Pennsylvania. Phase 1 goals of this project are to develop and validate methodologies that can quickly and cost-effectively identify wells with enhancement potential. We are currently in the final stages of developing and testing our new Microsoft(trademark) Access/Excel based software. We will be processing this well data and identifying potential candidate wells that can be used in Phase 2 to validate these methodologies. Preparation of the final technical report is underway

  10. ADVANCED TECHNOLOGIES FOR STRIPPER GAS WELL ENHANCEMENT

    International Nuclear Information System (INIS)

    Charles M. Boyer II; Ronald J. MacDonald P.G.

    2001-01-01

    As part of Task 1 in Advanced Technologies for Stripper Gas Well Enhancement, Schlumberger-Holditch Reservoir Technologies (H-RT) has joined with two Appalachian Basin producers, Great Lakes Energy Partners, LLC, and Belden and Blake Corporation to develop methodologies for identification and enhancement of stripper wells with economic upside potential. These industry partners have provided us with data for more than 700 wells in northwestern Pennsylvania. Phase 1 goals of this project are to develop and validate methodologies that can quickly and cost-effectively identify wells with enhancement potential. We have continued to enhance and streamline our software, and we are testing the final stages of our new Microsoft(trademark) Access/Excel based software. We are continuing to process this well data and are identifying potential candidate wells that can be used in Phase 2 to validate the new methodologies. In addition, preparation of the final technical report is underway

  11. Consortium for Petroleum & Natural Gas Stripper Wells

    Energy Technology Data Exchange (ETDEWEB)

    Morrison, Joel [Pennsylvania State Univ., University Park, PA (United States)

    2011-12-01

    The United States has more oil and gas wells than any other country. As of December 31, 2004, there were more than half a million producing oil wells in the United States. That is more than three times the combined total for the next three leaders: China, Canada, and Russia. The Stripper Well Consortium (SWC) is a partnership that includes domestic oil and gas producers, service and supply companies, trade associations, academia, the Department of Energy’s Strategic Center for Natural Gas and Oil (SCNGO) at the National Energy Technology Laboratory (NETL), and the New York State Energy Research and Development Authority (NYSERDA). The Consortium was established in 2000. This report serves as a final technical report for the SWC activities conducted over the May 1, 2004 to December 1, 2011 timeframe. During this timeframe, the SWC worked with 173 members in 29 states and three international countries, to focus on the development of new technologies to benefit the U.S. stripper well industry. SWC worked with NETL to develop a nationwide request-for-proposal (RFP) process to solicit proposals from the U.S. stripper well industry to develop and/or deploy new technologies that would assist small producers in improving the production performance of their stripper well operations. SWC conducted eight rounds of funding. A total of 132 proposals were received. The proposals were compiled and distributed to an industry-driven SWC executive council and program sponsors for review. Applicants were required to make a formal technical presentation to the SWC membership, executive council, and program sponsors. After reviewing the proposals and listening to the presentations, the executive council made their funding recommendations to program sponsors. A total of 64 projects were selected for funding, of which 59 were fully completed. Penn State then worked with grant awardees to issue a subcontract for their approved work. SWC organized and hosted a total of 14 meetings

  12. Harvesting Robots for High-value Crops: State-of-the-art Review and Challenges Ahead

    NARCIS (Netherlands)

    Bac, C.W.; Henten, van E.; Hemming, J.; Edan, Y.

    2014-01-01

    This review article analyzes state-of-the-art and future perspectives for harvesting robots in high-value crops. The objectives were to characterize the crop environment relevant for robotic harvesting, to perform a literature review on the state-of-the-art of harvesting robots using quantitative

  13. What You Should Know about Using Paint Strippers

    Science.gov (United States)

    ... is readily absorbed through the skin and may cause health problems. Adverse health effects in the developing fetus have been noted in laboratory animals exposed to some of the chemicals in paint strippers. Therefore, women of child-bearing age who work with or use paint strippers on a regular ...

  14. Harvester development for new high yielding SRC crops and markets

    International Nuclear Information System (INIS)

    2005-12-01

    Details are given of a project to develop a harvesting system that can produce fuel economically in a single pass to a required specification at a cost that is profitable for the grower while minimising the cost of the product. The project objectives listed include the development of a harvester drive chain and feeding systems to allow harvesting of the higher yielding crops now produced in the UK, determination of the most economic harvesting cycle for SRC crops, and production of fuels suitable for co-firing with coal in pulverised fuel systems or for gasification. The work programme and project conclusions are discussed

  15. Harvester development for new high yielding SRC crops and markets

    Energy Technology Data Exchange (ETDEWEB)

    Paulson, Mark

    2005-07-01

    This report describes the development of harvesting equipment for short rotation cultivation (SRC) crops produced in the UK that can produce fuel to a required specification in a single pass at a cost that is profitable for the grower while minimising the cost of the product. Details are given of the manufacture and installation of new components for large crop harvesting, and production of fuel suitable for co-firing in a coal combustion system using pulverised fuel and fuel suitable for gasification. The development of the drive chain to cope with the higher yielding crops, field tests on SRC crops, and determination of the most economic harvesting system are discussed along with the remanufacture of the chipping drum, and production of market chip samples. Harvesting guidance and an economic analysis of harvesting systems are presented.

  16. Harvester development for new high yielding SRC crops and markets

    International Nuclear Information System (INIS)

    Paulson, Mark

    2005-01-01

    This report describes the development of harvesting equipment for short rotation cultivation (SRC) crops produced in the UK that can produce fuel to a required specification in a single pass at a cost that is profitable for the grower while minimising the cost of the product. Details are given of the manufacture and installation of new components for large crop harvesting, and production of fuel suitable for co-firing in a coal combustion system using pulverised fuel and fuel suitable for gasification. The development of the drive chain to cope with the higher yielding crops, field tests on SRC crops, and determination of the most economic harvesting system are discussed along with the remanufacture of the chipping drum, and production of market chip samples. Harvesting guidance and an economic analysis of harvesting systems are presented

  17. ADVANCED TECHNOLOGIES FOR STRIPPER GAS WELL ENHANCEMENT

    International Nuclear Information System (INIS)

    Charles M. Boyer II; Ronald J. MacDonald P.G.

    2002-01-01

    As part of Task 1 in Advanced Technologies for Stripper Gas Well Enhancement, Schlumberger-Holditch Reservoir Technologies (H-RT) has joined with two Appalachian Basin producers, Great Lakes Energy Partners, LLC, and Belden and Blake Corporation to develop methodologies for identification and enhancement of stripper wells with economic upside potential. These industry partners have provided us with data for more than 700 wells in northwestern Pennsylvania. Phase 1 goals of this project are to develop and validate methodologies that can quickly and cost-effectively identify wells with enhancement potential. We have continued to enhance and streamline our software, and we are testing the final stages of our new Microsoft(trademark) Access/Excel based software. We are continuing to process the information and are identifying potential candidate wells that can be used in Phase 2 to validate the new methodologies. In addition, preparation of the final technical report is underway. During this quarter, we have presented our project and discussed the software to numerous Petroleum Technology Transfer Council (PTTC) workshops located in various regions of the United States

  18. Performance Evaluation of Hap-Free Paint Strippers vs. Methylene-Chloride-Based Strippers for Removing Army Chemical Agent Resistant Coatings (CARC)

    National Research Council Canada - National Science Library

    Kelley, John; Considine, Thomas

    2006-01-01

    ...). The purpose of this effort is to investigate HAP-free alternative chemical paint strippers as potential replacements for the methylene-chloride- based chemical strippers currently used in both processes...

  19. High Power Density, Lightweight Thermoelectric Metamaterials for Energy Harvesting

    Data.gov (United States)

    National Aeronautics and Space Administration — Thermoelectric energy harvesting utilizes materials that generate an electrical current when subjected to a temperature gradient, or simply, a hot and cold source of...

  20. ADVANCED STRIPPER GAS PRODUCED WATER REMEDIATION

    International Nuclear Information System (INIS)

    Ray W. Sheldon

    2001-01-01

    Natural gas and oil production from stripper wells also produces water contaminated with hydrocarbons, and in most locations, salts and trace elements. The hydrocarbons are not generally present in concentrations that allow the operator to economically recover these liquids. Produced liquids, (stripper gas water) which are predominantly water, present the operator with two options; purify the water to acceptable levels of contaminates, or pay for the disposal of the water. The project scope involves testing SynCoal as a sorbent to reduce the levels of contamination in stripper gas well produced water to a level that the water can be put to a productive use. Produced water is to be filtered with SynCoal, a processed sub-bituminous coal. It is expected that the surface area of and in the SynCoal would sorb the hydrocarbons and other contaminates and the effluent would be usable for agricultural purposes. Test plan anticipates using two well locations described as being disparate in the level and type of contaminates present. The loading capacity and the rate of loading for the sorbent should be quantified in field testing situations which include unregulated and widely varying liquid flow rates. This will require significant flexibility in the initial stages of the investigation. The scope of work outlined below serves as the guidelines for the testing of SynCoal carbon product as a sorbent to remove hydrocarbons and other contaminants from the produced waters of natural gas wells. A maximum ratio of 1 lb carbon to 100 lbs water treated is the initial basis for economic design. While the levels of contaminants directly impact this ratio, the ultimate economics will be dictated by the filter servicing requirements. This experimental program is intended to identify those treatment parameters that yield the best technological practice for a given set of operating conditions. The goal of this research is to determine appropriate guidelines for field trials by accurately

  1. High Frequency Supercapacitors for Piezo-based Energy Harvesting

    Science.gov (United States)

    Ervin, Matthew; Pereira, Carlos; Miller, John; Outlaw, Ronald; Rastegar, Jay; Murray, Richard

    2013-03-01

    Energy harvesting is being investigated as an alternative to batteries for powering munition guidance and fuzing functions during flight. A piezoelectric system that generates energy from the oscillation of a mass on a spring (set in motion by the launch acceleration) is being developed. Original designs stored this energy in an electrolytic capacitor for use during flight. Here we replace the electrolytic capacitor with a smaller, lighter, and potentially more reliable electrochemical double layer capacitor (aka, supercapacitor). The potential problems with using supercapacitors in this application are that the piezoelectric output greatly exceeds the supercapacitor electrolyte breakdown voltage, and the frequency greatly exceeds the operating frequency of commercial supercapacitors. Here we have investigated the use of ultrafast vertically oriented graphene array-based supercapacitors for storing the energy in this application. We find that the electrolyte breakdown is not a serious limitation as it is either kinetically limited by the relatively high frequency of the piezoelectric output, or it is overcome by the self-healing nature of supercapacitors. We also find that these supercapacitors have sufficient dynamic response to efficiently store the generated energy.

  2. Modeling and experiment to threshing unit of stripper combine ...

    African Journals Online (AJOL)

    Modeling and experiment to threshing unit of stripper combine. ... were conducted with the different feed rates and drum rotator speeds for the rice stripped mixtures. ... and damage as well as for threshing unit design and process optimization.

  3. High-efficiency passive full wave rectification for electromagnetic harvesters

    Science.gov (United States)

    Yilmaz, Mehmet; Tunkar, Bassam A.; Park, Sangtak; Elrayes, Karim; Mahmoud, Mohamed A. E.; Abdel-Rahman, Eihab; Yavuz, Mustafa

    2014-10-01

    We compare the performance of four types of full-wave bridge rectifiers designed for electromagnetic energy harvesters based on silicon diodes, Schottky diodes, passive MOSFETs, and active MOSFETs. Simulation and experimental results show that MOSFET-type rectifiers are more efficient than diode-type rectifiers, reaching voltage and power efficiency of 99% for ideal voltage source with input amplitudes larger than 800 mV. Since active MOSFETs require extra components and an external DC power supply, we conclude that passive MOSFETs are superior for micro-power energy harvesting systems. We demonstrate passive MOSFET rectifiers implemented using discrete, off-shelf components and show that they outperform all electromagnetic harvester rectifiers hitherto reported obtaining a power efficiency of 95%. Furthermore, we show that passive MOSFET rectifiers do not affect the center frequency, harvesting bandwidth, or optimal resistance of electromagnetic harvesters. We demonstrate a complete power management module by adding a capacitor to the rectifier output terminal. We found that this configuration changed the optimal resistive load from 40 Ω to 55 Ω and decreased output power efficiency to 86%.

  4. Intense heavy ion beam-induced effects in carbon-based stripper foils

    Energy Technology Data Exchange (ETDEWEB)

    Kupka, Katharina

    2016-08-15

    Amorphous carbon or carbon-based stripper foils are commonly applied in accelerator technology for electron stripping of ions. At the planned facility for antiproton and ion research (FAIR) at the Helmholtzzentrum fuer Schwerionenforschung (GSI), Darmstadt, thin carbon stripper foils provide an option for directly delivering ions of intermediate charge states to the heavy ion synchrotron, SIS 18, in order to mitigate space charge limitations during high-intensity operation. In case of desired high end-energies in the synchrotron, a second stripping process by a thicker carbon foil provides ions of higher charge states for injection into the SIS18. High beam intensities and a pulsed beam structure as foreseen at FAIR pose new challenges to the stripper foils which experience enhanced degradation by radiation damage, thermal effects, and stress waves. In order to ensure reliable accelerator operation, radiation-hard stripper foils are required. This thesis aims to a better understanding of processes leading to degradation of carbon-based thin foils. Special focus is placed on ion-beam induced structure and physical property changes and on the influence of different beam parameters. Irradiation experiments were performed at the M3-beamline of the universal linear accelerator (UNILAC) at GSI, using swift heavy ion beams with different pulse lengths and repetition rates. Tested carbon foils were standard amorphous carbon stripper foils produced by the GSI target laboratory, as well as commercial amorphous and diamond-like carbon foils and buckypaper foils. Microstructural changes were investigated with various methods such as optical microscopy, scanning electron microscopy (SEM), profilometry and chromatic aberration measurements. For the investigation of structural changes X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, high resolution transmission electron microscopy (HRTEM), in-situ Fourier-transform infrared spectroscopy (FTIR) and small angle X

  5. Intense heavy ion beam-induced effects in carbon-based stripper foils

    International Nuclear Information System (INIS)

    Kupka, Katharina

    2016-08-01

    Amorphous carbon or carbon-based stripper foils are commonly applied in accelerator technology for electron stripping of ions. At the planned facility for antiproton and ion research (FAIR) at the Helmholtzzentrum fuer Schwerionenforschung (GSI), Darmstadt, thin carbon stripper foils provide an option for directly delivering ions of intermediate charge states to the heavy ion synchrotron, SIS 18, in order to mitigate space charge limitations during high-intensity operation. In case of desired high end-energies in the synchrotron, a second stripping process by a thicker carbon foil provides ions of higher charge states for injection into the SIS18. High beam intensities and a pulsed beam structure as foreseen at FAIR pose new challenges to the stripper foils which experience enhanced degradation by radiation damage, thermal effects, and stress waves. In order to ensure reliable accelerator operation, radiation-hard stripper foils are required. This thesis aims to a better understanding of processes leading to degradation of carbon-based thin foils. Special focus is placed on ion-beam induced structure and physical property changes and on the influence of different beam parameters. Irradiation experiments were performed at the M3-beamline of the universal linear accelerator (UNILAC) at GSI, using swift heavy ion beams with different pulse lengths and repetition rates. Tested carbon foils were standard amorphous carbon stripper foils produced by the GSI target laboratory, as well as commercial amorphous and diamond-like carbon foils and buckypaper foils. Microstructural changes were investigated with various methods such as optical microscopy, scanning electron microscopy (SEM), profilometry and chromatic aberration measurements. For the investigation of structural changes X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, high resolution transmission electron microscopy (HRTEM), in-situ Fourier-transform infrared spectroscopy (FTIR) and small angle X

  6. Intense heavy ion beam-induced temperature effects in carbon-based stripper foils

    International Nuclear Information System (INIS)

    Kupka, K.; Tomut, M.; Simon, P.; Hubert, C.; Romanenko, A.; Lommel, B.; Trautmann, C.

    2015-01-01

    At the future FAIR facility, reliably working solid carbon stripper foils are desired for providing intermediate charge states to SIS18. With the expected high beam intensities, the foils experience enhanced degradation and limited lifetime due to severe radiation damage, stress waves, and thermal effects. This work presents systematic measurements of the temperature of different carbon-based stripper foils (amorphous, diamond-like, and carbon-nanotube based) exposed to 4.8 MeV/u U, Bi, and Au beams of different pulse intensities. Thermal and spectroscopic analyses were performed by means of infrared thermography and Fourier transform infrared spectroscopy. The resulting temperature depends on the foil thickness and strongly increases with increasing pulse intensity and repetition rate. (author)

  7. Nonlinear vibration analysis of the high-efficiency compressive-mode piezoelectric energy harvester

    Science.gov (United States)

    Yang, Zhengbao; Zu, Jean

    2015-04-01

    Power source is critical to achieve independent and autonomous operations of electronic mobile devices. The vibration-based energy harvesting is extensively studied recently, and recognized as a promising technology to realize inexhaustible power supply for small-scale electronics. Among various approaches, the piezoelectric energy harvesting has gained the most attention due to its high conversion efficiency and simple configurations. However, most of piezoelectric energy harvesters (PEHs) to date are based on bending-beam structures and can only generate limited power with a narrow working bandwidth. The insufficient electric output has greatly impeded their practical applications. In this paper, we present an innovative lead zirconate titanate (PZT) energy harvester, named high-efficiency compressive-mode piezoelectric energy harvester (HC-PEH), to enhance the performance of energy harvesters. A theoretical model was developed analytically, and solved numerically to study the nonlinear characteristics of the HC-PEH. The results estimated by the developed model agree well with the experimental data from the fabricated prototype. The HC-PEH shows strong nonlinear responses, favorable working bandwidth and superior power output. Under a weak excitation of 0.3 g (g = 9.8 m/s2), a maximum power output 30 mW is generated at 22 Hz, which is about ten times better than current energy harvesters. The HC-PEH demonstrates the capability of generating enough power for most of wireless sensors.

  8. Harvest season, high polluted season in East China

    International Nuclear Information System (INIS)

    Huang Xin; Song Yu; Li Mengmeng; Li Jianfeng; Zhu Tong

    2012-01-01

    East China, a major agricultural zone with a dense population, suffers from severe air pollution during June, the agricultural harvest season, every year. Crop burning emits tremendous amounts of combustion products into the atmosphere, not only rapidly degrading the local air quality but also affecting the tropospheric chemistry, threatening public health and affecting climate change. Recently, in mid-June 2012, crop fires left a thick pall of haze over East China. We evaluated the PM 10 , PM 2.5 (particulates less than 10 and 2.5 μm in aerodynamic diameter) and BC (black carbon) emissions by analyzing detailed census data and moderate resolution imaging spectroradiometer (MODIS) remote sensing images and then simulated the consequent pollution using meteorological and dispersion models. The results show that the crop fires sweeping from the south to the north are responsible for the intensive air pollution during harvest season. It is necessary for scientists and governments to pay more attention to this issue. (letter)

  9. Tests of prototype salt stripper system for IFR fuel cycle

    International Nuclear Information System (INIS)

    Carls, E.L.; Blaskovitz, R.J.; Johnson, T.R.; Ogata, T.

    1993-01-01

    One of the waste treatment steps for the on-site reprocessing of spent fuel from the Integral Fast Reactor fuel cycles is stripping of the electrolyte salt used in the electrorefining process. This involves the chemical reduction of the actinides and rare earth chlorides forming metals which then dissolve in a cadmium pool. To develop the equipment for this step, a prototype salt stripper system has been installed in an engineering scale argon-filled glovebox. Pumping trails were successful in transferring 90 kg of LiCl-KCl salt containing uranium and rare earth metal chlorides at 500 degree C from an electrorefiner to the stripper vessel at a pumping rate of about 5 L/min. The freeze seal solder connectors which were used to join sections of the pump and transfer line performed well. Stripping tests have commenced employing an inverted cup charging device to introduce a Cd-15 wt % Li alloy reductant to the stripper vessel

  10. High altitude species, high profits: can the trade in wild harvested Fritillaria cirrhosa (Liliaceae) be sustained?

    Science.gov (United States)

    Cunningham, A B; Brinckmann, J A; Pei, S-J; Luo, P; Schippmann, U; Long, X; Bi, Y-F

    2018-05-08

    in 2013, China exported over 44 tonnes of F. cirrhosa bulbs to Taiwan and 26.7 tonnes to the Republic of Korea. Extensive commercial use and limited wild stocks result in a high price (2,000 - 3,800 CNY per kg (around US$ 303 -560 per kg in 2017)) for F. cirrhosa bulbs. Prices of cultivated Fritillaria bulbs are much lower (600 - 680 CNY per kg in 2017) than wild harvested bulbs. But due to very specific growth requirements of F. cirrhosa, cultivation is not yet able to meet total demand. The consequence is continued exploitation of wild stocks. At the same time, however, an increasing proportion of the demand is met by cultivation of alternative Fritillaria species that are easier to grow than F. cirrhosa. The air-dry mass of F. cirrhosa bulbs varies between 0.0917 - 0.1116g per bulb. This represents 8960 - 10900 bulbs/kg or 8.9 - 10.9 million bulbs per tonne. Current demand therefore represents billions of bulbs per year. Demand for F. cirrhosa bulbs, particularly from China, makes this species one of the most intensively harvested alpine Himalayan medicinal bulbs. Although F. cirrhosa is listed as a Class III protected species in China, billions of these tiny, wild harvested bulbs are sold per year. Due to demand exceeding supply, the price of F. cirrhosa bulbs has increased dramatically. Between 2002 and 2017, for example, the price of wild harvested F. cirrhosa bulbs increased over nine-fold, from the equivalent of US$60 in 2002 to US$560 per kg in 2017. To date, cultivation has been unable to meet the entire market demand for F. cirrhosa bulbs, although other Fritillaria species are successfully cultivated on a larger scale. Copyright © 2018. Published by Elsevier B.V.

  11. Hybrid-type long-lived carbon stripper foils

    International Nuclear Information System (INIS)

    Sugai, Isao; Kato, Hajime

    1989-01-01

    A new method for the preparation of hybrid-type long-lived carbon stripper foils was developed. The new procedure is based on a modification of our controlled dc arc-discharge method. The carbon foils are of the multilayer type and the layers are composed of carbon particles emitted from the electrodes in the ac arc-discharge and from the cathode in the dc arc-discharge. With this simple and powerful method long lived carbon stripper foils can be prepared with higher reliability and reproducibility than with the previous procedure. (orig.)

  12. Low-head air stripper treats oil tanker ballast water

    International Nuclear Information System (INIS)

    Goldman, M.

    1992-01-01

    Prototype tests conducted during the winter of 1989/90 have successfully demonstrated an economical design for air stripping volatile hydrocarbons from oily tanker ballast water. The prototype air stripper, developed for Alyeska's Ballast Water Treatment (BWT) facility in Valdez, Alaska, ran continuously for three months with an average removal of 88% of the incoming volatile organics. Initially designed to remove oil and grease compounds from tanker ballast water, the BWT system has been upgraded to a three-step process to comply with new, stringent regulations. The BWT biological oxidation process enhances the growth of bacteria present in the incoming ballast water through nutrient addition, aeration, and recirculation within a complete-mixed bioreactor. The average removal of BETX is over 95%, however, occassional upsets required the placement of a polishing air stripper downstream of the aeration tanks. Packed-tower air stripping was investigated but deemed economically unfeasible for a facility that would only occasionally be used. Twelve feet of excess gravity head in the existing BWT hydraulic gradeline were employed to drive the air stripper feed. This limited the stripper packing depth to 8 feet and imposed constraints on the design of the inlet water and air distributors. Water distribution, air flow, temperature effects, and fouling from constituents in the ballast water were investigated. The prototype was operated under water and air flow conditions similar to those specified for the full-scale unit, and at a range of test conditions above and below the normal design conditions

  13. Radiation lifetimes and failure mechanisms of carbon stripper foils

    International Nuclear Information System (INIS)

    Auble, R.L.

    1981-01-01

    Measurements of lifetimes of thin carbon foils under heavy-ion irradiation are compiled and recent advances in stripper foil technology are reviewed. The impact of recent foil lifetime improvements, many by more than an order of magnitude, on heavy-ion electrostatic accelerators is discussed. Foil inhomogeneities, particularly those caused by sputtering are suggested to be a prime factor in usable foil lifetimes

  14. Impedance Based Characterization of a High-Coupled Screen Printed PZT Thick Film Unimorph Energy Harvester

    DEFF Research Database (Denmark)

    Lei, Anders; Xu, R.; Borregaard, L. M.

    2014-01-01

    The single degree of freedom mass-spring-damper system is the most common approach for deriving a full electromechanical model for the piezoelectric vibration energy harvester. In this paper, we revisit this standard electromechanical model by focusing on the impedance of the piezoelectric device...... parameters which, by means of the piezoelectric impedance expression, all can be determined accurately by electrical measurements. It is shown how four of five lumped parameters can be determined from a single impedance measurement scan, considerably reducing the characterization effort. The remaining...... parameter is determined from shaker measurements, and a highly accurate agreement is found between model and measurements on a unimorph MEMS-based screen printed PZT harvester. With a high coupling term K-2 Q similar or equal to 7, the harvester exhibits two optimum load points. The peak power performance...

  15. Petrol contaminated groundwater treatment with air-stripper in Balassagyarmat, Hungary

    International Nuclear Information System (INIS)

    Szabo, Peter; Bernath, Balazs

    2005-01-01

    extracted contaminated groundwater was conducted to the top of the tower and sprinkled into the air- stripper. A ventilator was connected to the bottom of the stripper, which blew the air with high pressure against the water stream. During the operation 4 544 m 3 groundwater was pumped out, cleaned, drained and 110 l of free phase hydrocarbon was skimmed

  16. U^{28+}-intensity record applying a H_{2}-gas stripper cell

    Directory of Open Access Journals (Sweden)

    Winfried Barth

    2015-04-01

    Full Text Available To meet the Facility for Antiproton and Ion Research science requirements higher beam intensity has to be achieved in the present GSI-accelerator complex. For this an advanced upgrade program for the UNILAC is ongoing. Stripping is a key technology for all heavy ion accelerators. For this an extensive research and development program was carried out to optimize for high brilliance heavy ion operation. After upgrade of the supersonic N_{2}-gas jet (2007, implementation of high current foil stripping (2011 and preliminary investigation of H_{2}-gas jet operation (2012, recently (2014 a new H_{2}-gas cell using a pulsed gas regime synchronized with arrival of the beam pulse has been developed. An obviously enhanced stripper gas density as well as a simultaneously reduced gas load for the pumping system result in an increased stripping efficiency, while the beam emittance remains the same. A new record intensity (7.8 emA for ^{238}U^{28+} beams at 1.4  MeV/u has been achieved applying the pulsed high density H_{2} stripper target to a high intensity ^{238}U^{4+} beam from the VARIS ion source with a newly developed extraction system. The experimental results are presented in detail.

  17. Impedance Matching Antenna-Integrated High-Efficiency Energy Harvesting Circuit

    Science.gov (United States)

    Shinki, Yuharu; Shibata, Kyohei; Mansour, Mohamed

    2017-01-01

    This paper describes the design of a high-efficiency energy harvesting circuit with an integrated antenna. The circuit is composed of series resonance and boost rectifier circuits for converting radio frequency power into boosted direct current (DC) voltage. The measured output DC voltage is 5.67 V for an input of 100 mV at 900 MHz. Antenna input impedance matching is optimized for greater efficiency and miniaturization. The measured efficiency of this antenna-integrated energy harvester is 60% for −4.85 dBm input power and a load resistance equal to 20 kΩ at 905 MHz. PMID:28763043

  18. Vibration-based energy harvesting with piezoelectrets having high d{sub 31} activity

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, X. [Institute for Telecommunications Technology, Technische Universität Darmstadt, Merckstr. 25, 64283 Darmstadt (Germany); School of Physics Science and Engineering, Tongji University, Siping Road 1239, Shanghai 200092 (China); Pondrom, P. [Institute for Telecommunications Technology, Technische Universität Darmstadt, Merckstr. 25, 64283 Darmstadt (Germany); System Reliability and Machine Acoustics SzM, Technische Universität Darmstadt, Magdalenenstr. 4, 64289 Darmstadt (Germany); Wu, L. [School of Physics Science and Engineering, Tongji University, Siping Road 1239, Shanghai 200092 (China); Sessler, G. M., E-mail: g.sessler@nt.tu-darmstadt.de [Institute for Telecommunications Technology, Technische Universität Darmstadt, Merckstr. 25, 64283 Darmstadt (Germany)

    2016-05-09

    Sandwiched fluoroethylene propylene films with charged, parallel-tunnel voids between the layers, which exhibit high d{sub 31} piezoelectric activity, were designed. Stripes of such piezoelectrets were exposed to mechanical stress in length direction by a seismic mass excited to vibrations. Due to the piezoelectricity of the films, a current in a terminating resistor is generated. The harvested power across the resistor amounts to about 0.2 mW for a seismic mass of 2 g and an acceleration of 1 g. In comparison with other piezoelectret or with poly(vinylidene fluoride) harvesters, the generated power referred to equal acceleration and force, is significantly larger.

  19. Impedance Matching Antenna-Integrated High-Efficiency Energy Harvesting Circuit

    Directory of Open Access Journals (Sweden)

    Yuharu Shinki

    2017-08-01

    Full Text Available This paper describes the design of a high-efficiency energy harvesting circuit with an integrated antenna. The circuit is composed of series resonance and boost rectifier circuits for converting radio frequency power into boosted direct current (DC voltage. The measured output DC voltage is 5.67 V for an input of 100 mV at 900 MHz. Antenna input impedance matching is optimized for greater efficiency and miniaturization. The measured efficiency of this antenna-integrated energy harvester is 60% for −4.85 dBm input power and a load resistance equal to 20 kΩ at 905 MHz.

  20. Impedance Matching Antenna-Integrated High-Efficiency Energy Harvesting Circuit.

    Science.gov (United States)

    Shinki, Yuharu; Shibata, Kyohei; Mansour, Mohamed; Kanaya, Haruichi

    2017-08-01

    This paper describes the design of a high-efficiency energy harvesting circuit with an integrated antenna. The circuit is composed of series resonance and boost rectifier circuits for converting radio frequency power into boosted direct current (DC) voltage. The measured output DC voltage is 5.67 V for an input of 100 mV at 900 MHz. Antenna input impedance matching is optimized for greater efficiency and miniaturization. The measured efficiency of this antenna-integrated energy harvester is 60% for -4.85 dBm input power and a load resistance equal to 20 kΩ at 905 MHz.

  1. Highly transparent triboelectric nanogenerator for harvesting water-related energy reinforced by antireflection coating

    Science.gov (United States)

    Liang, Qijie; Yan, Xiaoqin; Gu, Yousong; Zhang, Kui; Liang, Mengyuan; Lu, Shengnan; Zheng, Xin; Zhang, Yue

    2015-03-01

    Water-related energy is an inexhaustible and renewable energy resource in our environment, which has huge amount of energy and is not largely dictated by daytime and sunlight. The transparent characteristic plays a key role in practical applications for some devices designed for harvesting water-related energy. In this paper, a highly transparent triboelectric nanogenerator (T-TENG) was designed to harvest the electrostatic energy from flowing water. The instantaneous output power density of the T-TENG is 11.56 mW/m2. Moreover, with the PTFE film acting as an antireflection coating, the maximum transmittance of the fabricated T-TENG is 87.4%, which is larger than that of individual glass substrate. The T-TENG can be integrated with silicon-based solar cell, building glass and car glass, which demonstrates its potential applications for harvesting waste water energy in our living environment and on smart home system and smart car system.

  2. Robust piezoelectric composites for energy harvesting in high-strain environments

    NARCIS (Netherlands)

    Ende, D.A. van der; Groen, W.A.; Zwaag, S. van der

    2013-01-01

    High-strain environments, such as are found in automobile tires, provide deformation energy that can be harvested using piezoelectric materials, for instance, for powering electronics such as wireless sensors. Despite numerous efforts, none of the present devices easily satisfy the stringent

  3. Phytoremediation of high phosphorus soil by annual ryegrass and common bermudagrass harvest

    Science.gov (United States)

    Removal of soil phosphorus (P) in crop harvest is a remediation option for soils high in P. This four-year field-plot study determined P uptake by annual ryegrass (ARG, Lolium multiflorum Lam.) and common bermudagrass (CB, Cynodon dactylon (L.) Pers.) from Ruston soil (fine-loamy, siliceous, thermic...

  4. Novel Semiconducting Polymers for Highly Efficient Solar Energy Harvesting

    Science.gov (United States)

    2014-03-11

    we have developed an effective approach to enhance PCE and achieved an unprecedented high PCE value around 9.4%. S SS S X O O S SO OS S X S S X...Address: 128.135.225.61 Language: English (en-us,en;q=0.7,zh-cn;q=0.3) User Agent: Mozilla/5.0 (Windows NT 5.1; rv:27.0) Gecko/20100101 Firefox /27.0 Http

  5. Image Harvest: an open-source platform for high-throughput plant image processing and analysis.

    Science.gov (United States)

    Knecht, Avi C; Campbell, Malachy T; Caprez, Adam; Swanson, David R; Walia, Harkamal

    2016-05-01

    High-throughput plant phenotyping is an effective approach to bridge the genotype-to-phenotype gap in crops. Phenomics experiments typically result in large-scale image datasets, which are not amenable for processing on desktop computers, thus creating a bottleneck in the image-analysis pipeline. Here, we present an open-source, flexible image-analysis framework, called Image Harvest (IH), for processing images originating from high-throughput plant phenotyping platforms. Image Harvest is developed to perform parallel processing on computing grids and provides an integrated feature for metadata extraction from large-scale file organization. Moreover, the integration of IH with the Open Science Grid provides academic researchers with the computational resources required for processing large image datasets at no cost. Image Harvest also offers functionalities to extract digital traits from images to interpret plant architecture-related characteristics. To demonstrate the applications of these digital traits, a rice (Oryza sativa) diversity panel was phenotyped and genome-wide association mapping was performed using digital traits that are used to describe different plant ideotypes. Three major quantitative trait loci were identified on rice chromosomes 4 and 6, which co-localize with quantitative trait loci known to regulate agronomically important traits in rice. Image Harvest is an open-source software for high-throughput image processing that requires a minimal learning curve for plant biologists to analyzephenomics datasets. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  6. Image Harvest: an open-source platform for high-throughput plant image processing and analysis

    Science.gov (United States)

    Knecht, Avi C.; Campbell, Malachy T.; Caprez, Adam; Swanson, David R.; Walia, Harkamal

    2016-01-01

    High-throughput plant phenotyping is an effective approach to bridge the genotype-to-phenotype gap in crops. Phenomics experiments typically result in large-scale image datasets, which are not amenable for processing on desktop computers, thus creating a bottleneck in the image-analysis pipeline. Here, we present an open-source, flexible image-analysis framework, called Image Harvest (IH), for processing images originating from high-throughput plant phenotyping platforms. Image Harvest is developed to perform parallel processing on computing grids and provides an integrated feature for metadata extraction from large-scale file organization. Moreover, the integration of IH with the Open Science Grid provides academic researchers with the computational resources required for processing large image datasets at no cost. Image Harvest also offers functionalities to extract digital traits from images to interpret plant architecture-related characteristics. To demonstrate the applications of these digital traits, a rice (Oryza sativa) diversity panel was phenotyped and genome-wide association mapping was performed using digital traits that are used to describe different plant ideotypes. Three major quantitative trait loci were identified on rice chromosomes 4 and 6, which co-localize with quantitative trait loci known to regulate agronomically important traits in rice. Image Harvest is an open-source software for high-throughput image processing that requires a minimal learning curve for plant biologists to analyzephenomics datasets. PMID:27141917

  7. Magnetostrictive clad steel plates for high-performance vibration energy harvesting

    Science.gov (United States)

    Yang, Zhenjun; Nakajima, Kenya; Onodera, Ryuichi; Tayama, Tsuyoki; Chiba, Daiki; Narita, Fumio

    2018-02-01

    Energy harvesting technology is becoming increasingly important with the appearance of the Internet of things. In this study, a magnetostrictive clad steel plate for harvesting vibration energy was proposed. It comprises a cold-rolled FeCo alloy and cold-rolled steel joined together by thermal diffusion bonding. The performances of the magnetostrictive FeCo clad steel plate and conventional FeCo plate cantilevers were compared under bending vibration; the results indicated that the clad steel plate construct exhibits high voltage and power output compared to a single-plate construct. Finite element analysis of the cantilevers under bending provided insights into the magnetic features of a clad steel plate, which is crucial for its high performance. For comparison, the experimental results of a commercial piezoelectric bimorph cantilever were also reported. In addition, the cold-rolled FeCo and Ni alloys were joined by thermal diffusion bonding, which exhibited outstanding energy harvesting performance. The larger the plate volume, the more the energy generated. The results of this study indicated not only a promising application for the magnetostrictive FeCo clad steel plate as an efficient energy harvester, related to small vibrations, but also the notable feasibility for the formation of integrated units to support high-power trains, automobiles, and electric vehicles.

  8. Design of a new terminal gas stripper system

    International Nuclear Information System (INIS)

    Alvarez, Daniela E.; Amodei, Aldo J.; Bonino, Adrian G.; Bustos, Gustavo R.; Giannico, Matias A.; Serdeiro, Guillermo A.; Pomar, Cayetano

    2002-01-01

    A new terminal gas stripper, for the electrostatic FN tandem accelerator of the AMS system at the Nuclear Regulatory Authority in Argentina, is being designed at present. Most of the vacuum, electrical and electronic components are already available. The remote control of the system is being developed at LABI (Eng. Faculty, Buenos Aires University, Argentina). In order to construct the vacuum chamber, a collaboration with the LNLS (Campinas Univ, Sao Paulo, Brazil) is under consideration. The status of the project is presented. (author)

  9. Treatment of H0 and H- beams spilled at the stripper foil at full energy charge-exchange injection scheme

    International Nuclear Information System (INIS)

    Yamane, Isao

    1991-01-01

    The charge-exchange injection into a synchrotron to generate high-intensity pulsed proton beams for a spallation neutron source is reviewed while focusing on the treatment of H 0 and H - beams spilled at the stripper foil. After charge-exchange injection is briefly outlined, scattering by foil atoms and causes to spill H 0 and H - beams are described. These spilled beams can amount to several μA and should be carefully treated. It is then shown that a direct H - injection system needs to be considerably long and requires a very long straight section. Because of its simplicity, two-step H 0 injection has very wide applicability to various types of rings. However, it has a problem of emittance growth due to angular divergence in the stripper magnet and an ionoptical mismatch at the stripper foil. These problems are discussed, including a new proposal for a measure to remedy this problem. The laser photoionization injection is also briefly mentioned. (author)

  10. High temperature energy harvesters utilizing ALN/3C-SiC composite diaphragms

    Science.gov (United States)

    Lai, Yun-Ju; Li, Wei-Chang; Felmetsger, Valery V.; Senesky, Debbie G.; Pisano, Albert P.

    2014-06-01

    Microelectromechanical systems (MEMS) energy harvesting devices aiming at powering wireless sensor systems for structural health monitoring in harsh environments are presented. For harsh environment wireless sensor systems, sensor modules are required to operate at elevated temperatures (> 250°C) with capabilities to resist harsh chemical conditions, thereby the use of battery-based power sources becomes challenging and not economically efficient if considering the required maintenance efforts. To address this issue, energy harvesting technology is proposed to replace batteries and provide a sustainable power source for the sensor systems towards autonomous harsh environment wireless sensor networks. In particular, this work demonstrates a micromachined aluminum nitride/cubic silicon carbide (AlN/3C-SiC) composite diaphragm energy harvester, which enables high temperature energy harvesting from ambient pulsed pressure sources. The fabricated device yields an output power density of 87 μW/cm2 under 1.48-psi pressure pulses at 1 kHz while connected to a 14.6-kΩ load resistor. The effects of pulse profile on output voltage have been studied, showing that the output voltage can be maximized by optimizing the diaphragm resonance frequency based on specific pulse characteristics. In addition, temperature dependence of the diaphragm resonance frequency over the range of 20°C to 600°C has been investigated and the device operation at temperatures as high as 600°C has been verified.

  11. RELIABILITY TESTING OF AN ON-HARVESTER COTTON WEIGHT MEASUREMENT SYSTEM

    Science.gov (United States)

    A system for weighing seed cotton onboard stripper harvesters was developed and installed on several producer owned and operated machines. The weight measurement system provides critical information to producers when in the process of calibrating yield monitors or conducting on-farm research. The ...

  12. A High-Efficiency Wind Energy Harvester for Autonomous Embedded Systems.

    Science.gov (United States)

    Brunelli, Davide

    2016-03-04

    Energy harvesting is currently a hot research topic, mainly as a consequence of the increasing attractiveness of computing and sensing solutions based on small, low-power distributed embedded systems. Harvesting may enable systems to operate in a deploy-and-forget mode, particularly when power grid is absent and the use of rechargeable batteries is unattractive due to their limited lifetime and maintenance requirements. This paper focuses on wind flow as an energy source feasible to meet the energy needs of a small autonomous embedded system. In particular the contribution is on the electrical converter and system integration. We characterize the micro-wind turbine, we define a detailed model of its behaviour, and then we focused on a highly efficient circuit to convert wind energy into electrical energy. The optimized design features an overall volume smaller than 64 cm³. The core of the harvester is a high efficiency buck-boost converter which performs an optimal power point tracking. Experimental results show that the wind generator boosts efficiency over a wide range of operating conditions.

  13. A High-Efficiency Wind Energy Harvester for Autonomous Embedded Systems

    Science.gov (United States)

    Brunelli, Davide

    2016-01-01

    Energy harvesting is currently a hot research topic, mainly as a consequence of the increasing attractiveness of computing and sensing solutions based on small, low-power distributed embedded systems. Harvesting may enable systems to operate in a deploy-and-forget mode, particularly when power grid is absent and the use of rechargeable batteries is unattractive due to their limited lifetime and maintenance requirements. This paper focuses on wind flow as an energy source feasible to meet the energy needs of a small autonomous embedded system. In particular the contribution is on the electrical converter and system integration. We characterize the micro-wind turbine, we define a detailed model of its behaviour, and then we focused on a highly efficient circuit to convert wind energy into electrical energy. The optimized design features an overall volume smaller than 64 cm3. The core of the harvester is a high efficiency buck-boost converter which performs an optimal power point tracking. Experimental results show that the wind generator boosts efficiency over a wide range of operating conditions. PMID:26959018

  14. A High-Efficiency Wind Energy Harvester for Autonomous Embedded Systems

    Directory of Open Access Journals (Sweden)

    Davide Brunelli

    2016-03-01

    Full Text Available Energy harvesting is currently a hot research topic, mainly as a consequence of the increasing attractiveness of computing and sensing solutions based on small, low-power distributed embedded systems. Harvesting may enable systems to operate in a deploy-and-forget mode, particularly when power grid is absent and the use of rechargeable batteries is unattractive due to their limited lifetime and maintenance requirements. This paper focuses on wind flow as an energy source feasible to meet the energy needs of a small autonomous embedded system. In particular the contribution is on the electrical converter and system integration. We characterize the micro-wind turbine, we define a detailed model of its behaviour, and then we focused on a highly efficient circuit to convert wind energy into electrical energy. The optimized design features an overall volume smaller than 64 cm3. The core of the harvester is a high efficiency buck-boost converter which performs an optimal power point tracking. Experimental results show that the wind generator boosts efficiency over a wide range of operating conditions.

  15. Homogeneity analysis of high yield manufacturing process of mems-based pzt thick film vibrational energy harvesters

    DEFF Research Database (Denmark)

    Lei, Anders; Xu, Ruichao; Pedersen, C.M.

    2011-01-01

    This work presents a high yield wafer scale fabrication of MEMS-based unimorph silicon/PZT thick film vibrational energy harvesters aimed towards vibration sources with peak frequencies in the range of a few hundred Hz. By combining KOH etching with mechanical front side protection, SOI wafer...... to accurately define the thickness of the silicon part of the harvester and a silicon compatible PZT thick film screen-printing technique, we are able to fabricate energy harvesters on wafer scale with a yield higher than 90%. The characterization of the fabricated harvesters is focused towards the full wafer....../mass-production aspect; hence the analysis of uniformity in harvested power and resonant frequency....

  16. The stripper design and test at HIRFL-CSR

    International Nuclear Information System (INIS)

    Zhang Hongbin; Xiao Guoqing; Yuan Youjin; Xu Hushan; Li Zhankui; Lu Ziwei; Mao Ruishi; Zhao Tiecheng

    2010-01-01

    Charge stripping is employed to produce multi-charged ions for injecting the cooling storage ring. After penetrating through the carbon foil, the widened distribution of ion charge states poses a limit to the ion injection. Therefore, the carbon foil plays a key role in the charge stripping injection. In this paper,four strippers for Heavy Ion Research Facility at Lanzhou (HIRFL) and Cooling Storage Ring (CSR) are introduced. The charge state distribution of the stripped ions is measured and the stripping efficiency of the foils is investigated. The experimental results are consistent with the theoretical values. (authors)

  17. Highly efficient integrated rectifier and voltage boosting circuits for energy harvesting applications

    Directory of Open Access Journals (Sweden)

    D. Maurath

    2008-05-01

    Full Text Available This paper presents novel circuit concepts for integrated rectifiers and voltage converting interfaces for energy harvesting micro-generators. In the context of energy harvesting, usually only small voltages are supplied by vibration-driven generators. Therefore, rectification with minimum voltage losses and low reverse currents is an important issue. This is realized by novel integrated rectifiers which were fabricated and are presented in this article. Additionally, there is a crucial need for dynamic load adaptation as well as voltage up-conversion. A circuit concept is presented, which is able to obtain both requirements. This generator interface adapts its input impedance for an optimal energy transfer efficiency. Furthermore, this generator interface provides implicit voltage up-conversion, whereas the generator output energy is stored on a buffer, which is connected to the output of the voltage converting interface. As simulations express, this fully integrated converter is able to boost ac-voltages greater than |0.35 V| to an output dc-voltage of 2.0 V–2.5 V. Thereby, high harvesting efficiencies above 80% are possible within the entire operational range.

  18. Proper Estimation of the Energy Consumption in A Carbon Dioxide-MEA Stripper

    DEFF Research Database (Denmark)

    Madeddu, Claudio; Errico, Massimiliano; Baratti, Roberto

    In the field of CCS, the chemical absorption/desorption using amines represents one of the most easily implemented process for the reduction of the carbon dioxide generated by combustion plants. The high energy consumption in the solvent regeneration section represents the major concern for its...... fully industrial application. In the design of a carbon dioxide-MEA stripper, once the process targets are fixed, the estimation of the reboiler duty represents a crucial point for what concerns the quantification of the energy requirement. Furthermore, the vapor flow produced in the reboiler influences...... in simultaneous multicomponent material transfer, energy transfer and chemical reactions, is fundamental for an accurate design of the system. In this work the solvent regeneration section of a pilot-plant post-combustion CO2 capture facility was modeled using a rate-based approach, focusing on some key...

  19. Highly Adaptive Solid-Liquid Interfacing Triboelectric Nanogenerator for Harvesting Diverse Water Wave Energy.

    Science.gov (United States)

    Zhao, Xue Jiao; Kuang, Shuang Yang; Wang, Zhong Lin; Zhu, Guang

    2018-05-22

    Harvesting water wave energy presents a significantly practical route to energy supply for self-powered wireless sensing networks. Here we report a networked integrated triboelectric nanogenerator (NI-TENG) as a highly adaptive means of harvesting energy from interfacing interactions with various types of water waves. Having an arrayed networking structure, the NI-TENG can accommodate diverse water wave motions and generate stable electric output regardless of how random the water wave is. Nanoscaled surface morphology consisting of dense nanowire arrays is the key for obtaining high electric output. A NI-TENG having an area of 100 × 70 mm 2 can produce a stable short-circuit current of 13.5 μA and corresponding electric power of 1.03 mW at a water wave height of 12 cm. This merit promises practical applications of the NI-TENG in real circumstances, where water waves are highly variable and unpredictable. After energy storage, the generated electric energy can drive wireless sensing by autonomously transmitting data at a period less than 1 min. This work proposes a viable solution for powering individual standalone nodes in a wireless sensor network. Potential applications include but are not limited to long-term environment monitoring, marine surveillance, and off-shore navigation.

  20. Tritium stripping by a catalytic exchange stripper

    International Nuclear Information System (INIS)

    Heung, L.K.; Gibson, G.W.; Ortman, M.S.

    1991-01-01

    A catalytic exchange process for stripping elemental tritium from gas streams has been demonstrated. The process uses a catalyzed isotopic exchange reaction between tritium in the gas phase and protium or deuterium in the solid phase on alumina. The reaction is catalyzed by platinum deposited on the alumina. The process has been tested with both tritium and deuterium. Decontamination factors (ration of inlet and outlet tritium concentrations) as high as 1000 have been achieved, depending on inlet concentration. The test results and some demonstrated applications are presented

  1. Techno-Economic Analysis of a Secondary Air Stripper Process

    Energy Technology Data Exchange (ETDEWEB)

    Heberle, J.R. [Electric Power Research Inst. (EPRI), Palo Alto, CA (United States); Nikolic, Heather [Center for Applied Energy Research, University of Kentucky, Lexington, KY (United States); Thompson, Jesse [Center for Applied Energy Research, University of Kentucky, Lexington, KY (United States); Liu, Kunlei [Center for Applied Energy Research, University of Kentucky, Lexington, KY (United States); Pinkerton, Lora L. [WorleyParsons, Reading, PA (United States); Brubaker, David [WorleyParsons, Reading, PA (United States); Simpson, James C. [WorleyParsons, Reading, PA (United States); Wu, Song [Mitsubishi Hitachi Power Systems America, Inc, Basking Ridge, NJ (United States); Bhown, Abhoyjit S. [Electric Power Research Inst. (EPRI), Palo Alto, CA (United States)

    2017-08-22

    We present results of an initial techno-economic assessment on a post-combustion CO2 capture process developed by the Center for Applied Energy Research (CAER) at the University of Kentucky using Mitsubishi Hitachi Power Systems’ H3-1 aqueous amine solvent. The analysis is based on data collected at a 0.7 MWe pilot unit combined with laboratory data and process simulations. The process adds a secondary air stripper to a conventional solvent process, which increases the cyclic loading of the solvent in two ways. First, air strips additional CO2 from the solvent downstream of the conventional steam-heated thermal stripper. This extra stripping of CO2 reduces the lean loading entering the absorber. Second, the CO2-enriched air is then sent to the boiler for use as secondary air. This recycling of CO2 results in a higher concentration of CO2 in the flue gas sent to the absorber, and hence a higher rich loading of the solvent exiting the absorber. A process model was incorporated into a full-scale supercritical pulverized coal power plant model to determine the plant performance and heat and mass balances. The performance and heat and mass balance data were used to size equipment and develop cost estimates for capital and operating costs. Lifecycle costs were considered through a levelized cost of electricity (LCOE) assessment based on the capital cost estimate and modeled performance. The results of the simulations show that the CAER process yields a regeneration energy of 3.12 GJ/t CO2, a $53.05/t CO2 capture cost, and LCOE of $174.59/MWh. This compares to the U.S. Department of Energy’s projected costs (Case 10) of regeneration energy of 3.58 GJ/t CO2 , a $61.31/t CO2 capture cost, and LCOE of $189.59/MWh. For H3-1, the CAER process results in a regeneration energy of 2.62 GJ/tCO2 with a stripper pressure of 5.2 bar, a capture cost of $46.93/t CO2, and an LCOE of $164.33/MWh.

  2. Two-dimensional thermal simulations of aluminum and carbon ion strippers for experiments at SPIRAL2 using the highest beam intensities

    International Nuclear Information System (INIS)

    Tahir, N.A.; Kim, V.; Lamour, E.; Lomonosov, I.V.; Piriz, A.R.; Rozet, J.P.; Stöhlker, Th.; Sultanov, V.; Vernhet, D.

    2012-01-01

    In this paper we report on two-dimensional numerical simulations of heating of a rotating, wheel shaped target impacted by the full intensity of the ion beam that will be delivered by the SPIRAL2 facility at Caen, France. The purpose of this work is to study heating of solid targets that will be used to strip the fast ions of SPIRAL2 to the required high charge state for the FISIC (Fast Ion–Slow Ion Collision) experiments. Strippers of aluminum with different emissivities and of carbon are exposed to high beam current of different ion species as oxygen, neon and argon. These studies show that carbon, due to its much higher sublimation temperature and much higher emissivity, is more favorable compared to aluminum. For the highest beam intensities, an aluminum stripper does not survive. However, problem of the induced thermal stresses and long term material fatigue needs to be investigated before a final conclusion can be drawn.

  3. Carbon stripper foils held in place with carbon fibers

    International Nuclear Information System (INIS)

    Jolivet, Connie S.; Miller, Shawn A.; Stoner, John O.; Ladd, Peter

    2008-01-01

    The Spallation Neutron Source (SNS) currently under construction at Oak Ridge National Laboratory, Oak Ridge, Tennessee, is planned to initially utilize carbon stripper foils having areal densities approximately 260 μg/cm 2 . The projected design requires that each foil be supported by only one fixed edge. For stability of the foil, additional support is to be provided by carbon fibers. The feasibility of manufacturing and shipping such mounted carbon foils produced by arc evaporation was studied using two prototypes. Production of the foils is described. Fibers were chosen for satisfactory mechanical strength consistent with minimal interference with the SNS beam. Mounting of the fibers, and packaging of the assemblies for shipping are described. Ten completed assemblies were shipped to SNS for further testing. Preliminary evaluation of the survivability of the foils in the SNS foil changer is described

  4. Charge state distributions for heavy ions in carbon stripper foils

    International Nuclear Information System (INIS)

    McMahan, M.A.; Lebed, R.F.; Feinberg, B.

    1989-03-01

    We have extended the database of measured charge state distributions available in the literature through measurements at the SuperHILAC using carbon stripper foils in the energy range 1.2--8.5 MeV/u. Modifying a semi-empirical model to include the effect of electronic shells, we are able to correctly predict the mean charge state to within 1/2 a charge state for 6≤Z≤92 and energies from 30 keV/u to 16 MeV/u. We have determined parameters for the widths of the distributions for each electronic shell. For distributions lying across a shell boundary, we join the two Gaussians of different widths to get an asymmetric distribution. 18 refs., 4 figs., 2 tabs

  5. High-power density miniscale power generation and energy harvesting systems

    Energy Technology Data Exchange (ETDEWEB)

    Lyshevski, Sergey Edward [Department of Electrical and Microelectronics Engineering, Rochester Institute of Technology, Rochester, NY 14623-5603 (United States)

    2011-01-15

    This paper reports design, analysis, evaluations and characterization of miniscale self-sustained power generation systems. Our ultimate objective is to guarantee highly-efficient mechanical-to-electrical energy conversion, ensure premier wind- or hydro-energy harvesting capabilities, enable electric machinery and power electronics solutions, stabilize output voltage, etc. By performing the advanced scalable power generation system design, we enable miniscale energy sources and energy harvesting technologies. The proposed systems integrate: (1) turbine which rotates a radial- or axial-topology permanent-magnet synchronous generator at variable angular velocity depending on flow rate, speed and load, and, (2) power electronic module with controllable rectifier, soft-switching converter and energy storage stages. These scalable energy systems can be utilized as miniscale auxiliary and self-sustained power units in various applications, such as, aerospace, automotive, biotechnology, biomedical, and marine. The proposed systems uniquely suit various submersible and harsh environment applications. Due to operation in dynamic rapidly-changing envelopes (variable speed, load changes, etc.), sound solutions are researched, proposed and verified. We focus on enabling system organizations utilizing advanced developments for various components, such as generators, converters, and energy storage. Basic, applied and experimental findings are reported. The prototypes of integrated power generation systems were tested, characterized and evaluated. It is documented that high-power density, high efficiency, robustness and other enabling capabilities are achieved. The results and solutions are scalable from micro ({proportional_to}100 {mu}W) to medium ({proportional_to}100 kW) and heavy-duty (sub-megawatt) auxiliary and power systems. (author)

  6. High-power density miniscale power generation and energy harvesting systems

    International Nuclear Information System (INIS)

    Lyshevski, Sergey Edward

    2011-01-01

    This paper reports design, analysis, evaluations and characterization of miniscale self-sustained power generation systems. Our ultimate objective is to guarantee highly-efficient mechanical-to-electrical energy conversion, ensure premier wind- or hydro-energy harvesting capabilities, enable electric machinery and power electronics solutions, stabilize output voltage, etc. By performing the advanced scalable power generation system design, we enable miniscale energy sources and energy harvesting technologies. The proposed systems integrate: (1) turbine which rotates a radial- or axial-topology permanent-magnet synchronous generator at variable angular velocity depending on flow rate, speed and load, and, (2) power electronic module with controllable rectifier, soft-switching converter and energy storage stages. These scalable energy systems can be utilized as miniscale auxiliary and self-sustained power units in various applications, such as, aerospace, automotive, biotechnology, biomedical, and marine. The proposed systems uniquely suit various submersible and harsh environment applications. Due to operation in dynamic rapidly-changing envelopes (variable speed, load changes, etc.), sound solutions are researched, proposed and verified. We focus on enabling system organizations utilizing advanced developments for various components, such as generators, converters, and energy storage. Basic, applied and experimental findings are reported. The prototypes of integrated power generation systems were tested, characterized and evaluated. It is documented that high-power density, high efficiency, robustness and other enabling capabilities are achieved. The results and solutions are scalable from micro (∼100 μW) to medium (∼100 kW) and heavy-duty (sub-megawatt) auxiliary and power systems.

  7. Image processing for stripper harvested cotton trash content measurement a progress report

    Science.gov (United States)

    This study was initiated to provide the basis for obtaining on-line information as to the levels of the various types of gin trash. The objective is to provide the ginner with knowledge of the quantity of the various trash components in the raw uncleaned seed cotton. This information is currently no...

  8. A portable high-efficiency electromagnetic energy harvesting system using supercapacitors for renewable energy applications in railroads

    International Nuclear Information System (INIS)

    Zhang, Xingtian; Zhang, Zutao; Pan, Hongye; Salman, Waleed; Yuan, Yanping; Liu, Yujie

    2016-01-01

    Graphical abstract: In this study, we develop a portable high-efficiency electromagnetic energy harvesting system with supercapacitors that converts the energy of track vibrations into electricity. The generated electricity is stored in the supercapacitors and used in remote areas for safety facilities or in standby power supplies for rail-side equipment. The proposed system consists of a mechanical transmission and a rectifier. Acting as the energy input and transmission, Gears and a rack amplify the small vibrations of the track, and one-way bearings enhance efficiency by transforming bidirectional motion to unidirectional rotation. Supercapacitors are used in the energy harvesting system for the first time. The supercapacitors permit the storage of energy from rapidly changing transient currents and a steady power supply for external loads. The proposed system is demonstrated through dynamic simulations, which show the rapid response of the system. An efficiency of 55.5% is demonstrated in bench tests, verifying that the proposed electromagnetic energy harvesting system is effective and practical in renewable energy applications for railroads. - Highlights: • A frequently ignored source of energy, railroad track vibrations, is harvested. • A novel conversion mechanism is designed to maximize efficiency. • Supercapacitors are included in the electromagnetic energy harvesting system. • A portable design is proposed for wider application. - Abstract: As the demand for alternative sources of energy has increased, harvesting abundant environmental energy such as vibration energy including track vibrations in railway systems has attracted greater attention. In this study, we develop a portable high-efficiency electromagnetic energy harvesting system with supercapacitors that converts the energy of track vibrations into electricity. The generated electricity is stored in the supercapacitors and used in remote areas for safety facilities or in standby power

  9. Stabilising high energy orbit oscillations by the utilisation of centrifugal effects for rotating-tyre-induced energy harvesting

    Science.gov (United States)

    Zhang, Yunshun; Zheng, Rencheng; Nakano, Kimihiko; Cartmell, Matthew P.

    2018-04-01

    Nonlinear energy harvesters are frequently considered in preference to linear devices because they can potentially overcome the narrow frequency bandwidth limitations inherent to linear variants; however, the possibility of variable harvesting efficiency is raised for the nonlinear case. This paper proposes a rotational energy harvester which may be fitted into an automobile tyre, with the advantage that it may broaden the rotating frequency bandwidth and simultaneously stabilise high-energy orbit oscillations. By consideration of the centrifugal effects due to rotation, the overall restoring force will potentially be increased for a cantilever implemented within the harvester, and this manifests as an increase in its equivalent elastic stiffness. In addition, this study reveals that the initial potential well barriers become as shallow as those for a bistable system. When the rotational frequency increases beyond an identifiable boundary frequency, the system transforms into one with a potential barrier of a typical monostable system. On this basis, the inter-well motion of the bistable system can provide sufficient kinetic energy so that the cantilever maintains its high-energy orbit oscillation for monostable hardening behaviour. Furthermore, in a vehicle drive experiment, it has been shown that the effective rotating frequency bandwidth can be widened from 15 km/h-25 km/h to 10 km/h-40 km/h. In addition, it is confirmed that the centrifugal effects can improve the harvester performance, producing a mean power of 61 μW at a driving speed of 40 km/h, and this is achieved by stabilising the high-energy orbit oscillations of the rotational harvester.

  10. Comparison of different options for harvest of a therapeutic protein product from high cell density yeast fermentation broth.

    Science.gov (United States)

    Wang, Alice; Lewus, Rachael; Rathore, Anurag S

    2006-05-05

    Recovery of therapeutic protein from high cell density yeast fermentations at commercial scale is a challenging task. In this study, we investigate and compare three different harvest approaches, namely centrifugation followed by depth filtration, centrifugation followed by filter-aid enhanced depth filtration, and microfiltration. This is achieved by presenting a case study involving recovery of a therapeutic protein from Pichia pastoris fermentation broth. The focus of this study is on performance of the depth filtration and the microfiltration steps. The experimental data has been fitted to the conventional models for cake filtration to evaluate specific cake resistance and cake compressibility. In the case of microfiltration, the experimental data agrees well with flux predicted by shear induced diffusion model. It is shown that, under optimal conditions, all three options can deliver the desired product recovery ( >80%), harvest time ( making a final decision on a harvesting approach.

  11. Investigating Forest Harvest Effects on DOC Concentration and Quality: An In Situ, High Resolution Approach to Quantifying DOC Export Dynamics

    Science.gov (United States)

    Jollymore, A. J.; Johnson, M. S.; Hawthorne, I.

    2013-12-01

    Justification: Forest harvest effects on water quality can signal alterations in hydrologic and ecologic processes incurred as a result of forest harvest activities. Organic matter (OM), specifically dissolved organic carbon (DOC), plays a number of important roles mediating UV-light penetration, redox reactivity and microbial activity within aquatic ecosystems. Quantification of DOC is typically pursued via grab sampling followed by chemical or spectrophotometric analysis, limiting the temporal resolution obtained as well as the accuracy of export calculations. The advent of field-deployable sensors capable of measuring DOC concentration and certain quality characteristics in situ provides the ability to observe dynamics at temporal scales necessary for accurate calculation of DOC flux, as well as the observation of dynamic changes in DOC quality on timescales impossible to observe through grab sampling. Methods: This study utilizes a field deployable UV-Vis spectrophotometer (spectro::lyzer, s::can, Austria) to investigate how forest harvest affects DOC export. The sensor was installed at an existing hydrologic monitoring site at the outlet of a headwater stream draining a small (91 hectare) second growth Douglasfir-dominated catchment near Campbell River on Vancouver Island, British Columbia. Measurement began late in 2009, prior to forest harvest and associated activities such as road building (which commenced in October 2010 and ended in early 2011), and continues to present. During this time - encompassing the pre, during and post-harvest conditions - the absorbance spectrum of stream water from 200 to 750 nm was measured. DOC concentration and spectroscopic indices related to DOC quality (including SUVA, which relates to the concentration of aromatic carbon, and spectral slope) were subsequently calculated for each spectra obtained at 30-minute intervals. Results and conclusions: High frequency measurements of DOC show that overall export of OM increased in

  12. High-resolution AFM topographs of Rubrivivax gelatinosus light-harvesting complex LH2

    Science.gov (United States)

    Scheuring, Simon; Reiss-Husson, Francoise; Engel, Andreas; Rigaud, Jean-Louis; Ranck, Jean-Luc

    2001-01-01

    Light-harvesting complexes 2 (LH2) are the accessory antenna proteins in the bacterial photosynthetic apparatus and are built up of αβ-heterodimers containing three bacteriochlorophylls and one carotenoid each. We have used atomic force microscopy (AFM) to investigate reconstituted LH2 from Rubrivivax gelatinosus, which has a C-terminal hydrophobic extension of 21 amino acids on the α-subunit. High-resolution topographs revealed a nonameric organization of the regularly packed cylindrical complexes incorporated into the membrane in both orientations. Native LH2 showed one surface which protruded by ∼6 Å and one that protruded by ∼14 Å from the membrane. Topographs of samples reconstituted with thermolysin-digested LH2 revealed a height reduction of the strongly protruding surface to ∼9 Å, and a change of its surface appearance. These results suggested that the α-subunit of R.gelatinosus comprises a single transmembrane helix and an extrinsic C-terminus, and allowed the periplasmic surface to be assigned. Occasionally, large rings (∼120 Å diameter) surrounded by LH2 rings were observed. Their diameter and appearance suggest the large rings to be LH1 complexes. PMID:11406579

  13. A distribution-free multi-factorial profiler for harvesting information from high-density screenings.

    Science.gov (United States)

    Besseris, George J

    2013-01-01

    Data screening is an indispensable phase in initiating the scientific discovery process. Fractional factorial designs offer quick and economical options for engineering highly-dense structured datasets. Maximum information content is harvested when a selected fractional factorial scheme is driven to saturation while data gathering is suppressed to no replication. A novel multi-factorial profiler is presented that allows screening of saturated-unreplicated designs by decomposing the examined response to its constituent contributions. Partial effects are sliced off systematically from the investigated response to form individual contrasts using simple robust measures. By isolating each time the disturbance attributed solely to a single controlling factor, the Wilcoxon-Mann-Whitney rank stochastics are employed to assign significance. We demonstrate that the proposed profiler possesses its own self-checking mechanism for detecting a potential influence due to fluctuations attributed to the remaining unexplainable error. Main benefits of the method are: 1) easy to grasp, 2) well-explained test-power properties, 3) distribution-free, 4) sparsity-free, 5) calibration-free, 6) simulation-free, 7) easy to implement, and 8) expanded usability to any type and size of multi-factorial screening designs. The method is elucidated with a benchmarked profiling effort for a water filtration process.

  14. Anoxic oscillating MBR for photosynthetic bacteria harvesting and high salinity wastewater treatment.

    Science.gov (United States)

    Qin, Lei; Liu, Qiuhua; Meng, Qin; Fan, Zheng; He, Jinzhe; Liu, Tao; Shen, Chong; Zhang, Guoliang

    2017-01-01

    In this study, photosynthetic bacteria (PSB) were first harvested by MBR with pendulum type oscillation (PTO) hollow fiber module in succession and on a large scale. Based on unique properties of PSB, PSB/MBR was successfully applied for high-salinity wastewater treatment. Compared with control PSB-MBR (CMBR), PSB/PTO-MBR exhibited more excellent organics removal, which was mainly attributed to much higher biomass production for utilization. Meanwhile, the influence of light irradiation and aeration on activity of PSB was investigated in detail. Results showed that PTO-MBR with 12h light irradiation proved to be a promising and economical alternative. The cycle of dark/light and anoxic had a positive effect on PSB cultivating. Moreover, PTO-MBR exhibited much higher flux than CMBR even if large amounts of biomass existed, which demonstrated that the strong shear stress on interface of liquid-membrane played important roles on membrane fouling reduction. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. A distribution-free multi-factorial profiler for harvesting information from high-density screenings.

    Directory of Open Access Journals (Sweden)

    George J Besseris

    Full Text Available Data screening is an indispensable phase in initiating the scientific discovery process. Fractional factorial designs offer quick and economical options for engineering highly-dense structured datasets. Maximum information content is harvested when a selected fractional factorial scheme is driven to saturation while data gathering is suppressed to no replication. A novel multi-factorial profiler is presented that allows screening of saturated-unreplicated designs by decomposing the examined response to its constituent contributions. Partial effects are sliced off systematically from the investigated response to form individual contrasts using simple robust measures. By isolating each time the disturbance attributed solely to a single controlling factor, the Wilcoxon-Mann-Whitney rank stochastics are employed to assign significance. We demonstrate that the proposed profiler possesses its own self-checking mechanism for detecting a potential influence due to fluctuations attributed to the remaining unexplainable error. Main benefits of the method are: 1 easy to grasp, 2 well-explained test-power properties, 3 distribution-free, 4 sparsity-free, 5 calibration-free, 6 simulation-free, 7 easy to implement, and 8 expanded usability to any type and size of multi-factorial screening designs. The method is elucidated with a benchmarked profiling effort for a water filtration process.

  16. Wind energy harvesting with a piezoelectric harvester

    International Nuclear Information System (INIS)

    Wu, Nan; Wang, Quan; Xie, Xiangdong

    2013-01-01

    An energy harvester comprising a cantilever attached to piezoelectric patches and a proof mass is developed for wind energy harvesting, from a cross wind-induced vibration of the cantilever, by the electromechanical coupling effect of piezoelectric materials. The vibration of the cantilever under the cross wind is induced by the air pressure owing to a vortex shedding phenomenon that occurs on the leeward side of the cantilever. To describe the energy harvesting process, a theoretical model considering the cross wind-induced vibration on the piezoelectric coupled cantilever energy harvester is developed, to calculate the charge and the voltage from the harvester. The influences of the length and location of the piezoelectric patches as well as the proof mass on the generated electric power are investigated. Results show that the total generated electric power can be as high as 2 W when the resonant frequency of the cantilever harvester is close to the vortex shedding frequency. Moreover, a value of total generated electric power up to 1.02 W can be practically realized for a cross wind with a variable wind velocity of 9–10 m s −1 by a harvester with a length of 1.2 m. This research facilitates an effective and compact wind energy harvesting device. (paper)

  17. Highly efficient green light harvesting from Mg doped ZnO nanoparticles: Structural and optical studies

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Sarla, E-mail: mail2sarlasharma@gmail.com [Department of Physics, University of Rajasthan, Jaipur 302055 (India); Vyas, Rishi [Department of Physics, Malaviya National Institute of Technology, Jaipur 302017 (India); Sharma, Neha [Department of Physics, University of Rajasthan, Jaipur 302055 (India); Singh, Vidyadhar [Okinawa Institute of Science and Technology, Graduate University, Okinawa 9040495 (Japan); Singh, Arvind [Department of Physics, Institute of Chemical Technology, Mumbai 400 019 (India); Kataria, Vanjula; Gupta, Bipin Kumar [National Physical Laboratory (CSIR), New Delhi 110012 (India); Vijay, Y.K. [Department of Physics, University of Rajasthan, Jaipur 302055 (India)

    2013-03-05

    Graphical abstract: Demonstration of highly efficient green light emission harvesting from Mg doped ZnO nanoparticles were synthesized via facile wet chemical route with an average particle size ∼15 nm. The resulted nanoparticles exhibit intense green emission peaking at 530 nm upon 325 nm excitation. The photoluminescence (PL) intensity of visible emission depends upon the doping concentration of Mg. The PL intensity was found maximum up to 4% doping of Mg and beyond it exhibits a decrees in emission. The obtained highly luminescent green emission of ZnO nanoparticle would be an ultimate choice for next generation optoelectronics device materials. Highlights: ► Zn{sub 1−x}Mg{sub x}O nanoparticles were prepared by mechanochemical processing. ► High blue emission intensity was observed contrary to previous reports. ► Blue emission is suggested to be originating from the high density of defects. ► Defect density in as-milled condition is very high resulting in high emission. ► Mg promoted non-radiative recombination and lowered intensities. -- Abstract: Highly efficient green light emission was observed from Mg doped ZnO nanoparticles synthesized via facile wet chemical route with an average particle size ∼15 nm. The XRD analysis confirmed the growth of wurtzite phase of ZnO nanoparticles. Moreover, the optical properties of these nanoparticles were investigated by different spectroscopic techniques. The resulted nanoparticles exhibit intense green emission peaking at 530 nm (2.34 eV) upon 325 nm (3.81 eV) excitation. The photoluminescence (PL) intensity of visible emission depends upon the doping concentration of Mg. The PL intensity was found maximum up to 4% doping of Mg, and beyond it exhibits a decrees in emission. Furthermore, by varying the band gap from 3.50 to 3.61 eV, the PL spectra showed a near band edge (NBE) emission at wavelength around 370 nm (3.35 eV) and a broad deep level emission in the visible region. The obtained highly

  18. Preparation and investigation of diamond-like carbon stripper foils by filtered cathodic vacuum arc

    International Nuclear Information System (INIS)

    Fan, Qiwen; Du, Yinghui; Zhang, Rong; Xu, Guoji

    2013-01-01

    Thin diamond-like carbon (DLC) stripper foils ∼5μg/cm 2 in thickness were produced and evaluated as heavy-ion strippers for the Beijing HI-13 Tandem Accelerator. The DLC layers ∼4μg/cm 2 in thickness were produced by the filtered cathodic vacuum arc technology onto glass slides coated with betaine–saccharose as releasing agent, which were previously covered with evaporated carbon layers ∼1μg/cm 2 in thickness by the controlled ac arc-discharge method. Irradiation lifetimes of the DLC stripper foils were tested using the heavy-ion beams at the terminal of the Beijing HI-13 Tandem Accelerator, and compared with those of the standard carbon stripper foils made by the combined dc and ac arc-discharge method. The measurements indicate that the DLC stripper foils outlast the standard combined dc and ac arc-discharge carbon stripper foils by a factor of at least 13 and 4 for the 197 Au − (∼9MeV, ∼1μA) and 63 Cu − (∼9MeV, ∼1μA) ion beams, respectively. The structure and properties of the DLC foils deposited onto silicon substrates by the filtered cathodic vacuum arc technology were also evaluated and analyzed by scanning electron microscopy, Raman spectroscopy and X-ray photoelectron spectroscopy. The scanning electron microscopy images show that the DLC foils contain hardly droplets through the double 90° filters. The X-ray photoelectron spectrum indicates that sp 3 bonds of the DLC foils exceed 70%. The integral intensity ratio of the D peak to the G peak (I D /I G ) measured by the Raman spectroscopy is 0.78

  19. Flexible Semitransparent Energy Harvester with High Pressure Sensitivity and Power Density Based on Laterally Aligned PZT Single-Crystal Nanowires.

    Science.gov (United States)

    Zhao, Quan-Liang; He, Guang-Ping; Di, Jie-Jian; Song, Wei-Li; Hou, Zhi-Ling; Tan, Pei-Pei; Wang, Da-Wei; Cao, Mao-Sheng

    2017-07-26

    A flexible semitransparent energy harvester is assembled based on laterally aligned Pb(Zr 0.52 Ti 0.48 )O 3 (PZT) single-crystal nanowires (NWs). Such a harvester presents the highest open-circuit voltage and a stable area power density of up to 10 V and 0.27 μW/cm 2 , respectively. A high pressure sensitivity of 0.14 V/kPa is obtained in the dynamic pressure sensing, much larger than the values reported in other energy harvesters based on piezoelectric single-crystal NWs. Furthermore, theoretical and finite element analyses also confirm that the piezoelectric voltage constant g 33 of PZT NWs is competitive to the lead-based bulk single crystals and ceramics, and the enhanced pressure sensitivity and power density are substantially linked to the flexible structure with laterally aligned PZT NWs. The energy harvester in this work holds great potential in flexible and transparent sensing and self-powered systems.

  20. A new method for making long-lived carbon stripper foils

    International Nuclear Information System (INIS)

    Sugai, Isao; Ishii, Sabro; Hattori, Toshiyuki; Muto, Hideshi; Takahashi, Yohsuke; Kato, Hajime; Yamazaki, Kuniaki.

    1989-01-01

    We have developed a new method for preparation of long-lived carbon stripper foils, based on the modification of our 'controlled DC arc-discharge method'. The carbon foils consist of multi-layers, and carbon particles in each layer are emitted from the electrode in AC arc-discharge or from the cathode electrode in DC arc-discharge. The lifetimes of the carbon foils made by the new method are equal to or longer than those prepared by the controlled DC arc-discharge method. The new method is simple and powerful to make long-lived carbon stripper foils with higher reliability and reproducibility than the previous method. (author)

  1. Analysis of fruit and oil quantity and quality distribution in high-density olive trees in order to improve the mechanical harvesting process

    Energy Technology Data Exchange (ETDEWEB)

    Castillo-Ruiz, F. J.; Jiménez-Jiménez, F.; Blanco-Roldán, G.L.; Sola-Guirado, R. R.; Agüera-Vega, J.; Castro-Garcia, S.

    2015-07-01

    Olive fruit production and oil quality distribution with respect to canopy distribution are important criteria for selection and improvement of mechanical harvesting methods. Tests were performed in a high-density olive orchard (Olea europea L., cv. Arbequina) in southern Spain. Fruit distribution, fruit properties and oil parameters were measured by taken separate samples for each canopy location and tree. Results showed a high percentage of fruits and oil located in the middle-outer and upper canopy, representing more than 60% of total production. The position of these fruits along with their higher weight per fruit, maturity index and polyphenol content make them the target for all mechanical harvesting systems. The fruits from the lower canopy represented close to 30% of fruit and oil production, however, the mechanical harvesting of these fruits is inefficient for mechanical harvesting systems. Whether these fruits cannot be properly harvested, enhance tree training to raise their position is recommended. Fruits located inside the canopy are not a target location for mechanical harvesting systems as they were a small percentage of the total fruit (<10%). Significant differences were found for polyphenol content with respect to canopy height, although this was not the case with acidity. In addition, the ripening index did not influence polyphenol content and acidity values within the canopy. Fruit production, properties and oil quality varied depending on fruit canopy position. Thus harvesting systems may be targeted at maximize harvesting efficiency including an adequate tree training system adapted to the harvesting system. (Author)

  2. Analysis of fruit and oil quantity and quality distribution in high-density olive trees in order to improve the mechanical harvesting process

    Directory of Open Access Journals (Sweden)

    Francisco J. Castillo-Ruiz

    2015-06-01

    Full Text Available Olive fruit production and oil quality distribution with respect to canopy distribution are important criteria for selection and improvement of mechanical harvesting methods. Tests were performed in a high-density olive orchard (Olea europea L., cv. Arbequina in southern Spain. Fruit distribution, fruit properties and oil parameters were measured by taken separate samples for each canopy location and tree. Results showed a high percentage of fruits and oil located in the middle-outer and upper canopy, representing more than 60% of total production. The position of these fruits along with their higher weight per fruit, maturity index and polyphenol content make them the target for all mechanical harvesting systems. The fruits from the lower canopy represented close to 30% of fruit and oil production, however, the mechanical harvesting of these fruits is inefficient for mechanical harvesting systems. Whether these fruits cannot be properly harvested, enhance tree training to raise their position is recommended. Fruits located inside the canopy are not a target location for mechanical harvesting systems as they were a small percentage of the total fruit (<10%. Significant differences were found for polyphenol content with respect to canopy height, although this was not the case with acidity. In addition, the ripening index did not influence polyphenol content and acidity values within the canopy. Fruit production, properties and oil quality varied depending on fruit canopy position. Thus harvesting systems may be targeted at maximize harvesting efficiency including an adequate tree training system adapted to the harvesting system.

  3. Stripper, shut-in and orphan wells in joint operations

    International Nuclear Information System (INIS)

    Nixon, R.

    1999-01-01

    Low productivity wells, stripper wells, can be an excellent source of income to independent operators or small companies, but a serious financial burden for larger companies. Shut-in wells, for most companies, are either waiting on a market and production facilities, or represent deferred abandonment liabilities. Orphan wells also reflect financial distress. The firm, Cord Oil and Gas Management Ltd., was formed in 1986 to specifically assist oil and gas companies, sophisticated investors and financial institutions with the management, enhancement and disposition of non-core or low productivity assets. This type of production, depending on the number of wells and cumulative production, can be the life blood of a small organization or a serious drain on the administrative personnel and financial resources of larger organizations. Philosophically, industry and/or government needs to manage the eventuality of abandonments by establishing financial criteria. Some suggestions for industry include: (1) establish provisions within joint operating agreements to set aside an abandonment and environmental cleanup fund; (2) minimize the inventory of abandonment candidates by an ongoing program of reclamation; (3) offset abandonment costs with salvage value of tangible equipment under AFE approval; and (4) voluntarily restrict transfer abandonment liabilities with producing assets on a selective basis. Some suggestions for governments include: (1) fund the orphan well by a deposit for every well drilled; (2) restrict the transfer of liabilities for abandoned and inactive wells by ensuring that the transferee is financially capable; and (3) access the chain of title to ensure non-operators remain responsible for the proportionate shares of abandonment and cleanup costs

  4. Harvested wood products and carbon sink in a young beech high forest

    Directory of Open Access Journals (Sweden)

    Pilli R

    2008-03-01

    Full Text Available According to art. 3.4 of the Kyoto Protocol (KP, Italy has elected forest management as additional human-induced activity to attain the goal of reduction in greenhouse gas emissions. The whole forest area not subjected to afforestation, reforestation or deforestation processes since 1990 will be considered as managed forest. In order to analyse different management strategies, the Carbon-Pro Project, involving 9 partners of the European CADSES area, considered a young beech high forest (ex-coppice, defined as "transitory silvicultural system" as a common case study for the Pre-alps region. Using data collected with forest plans during the period 1983 - 2005, aboveground and belowground forest carbon stock and sink of a specific forest compartment were estimated by the Carbon Stock Method proposed by the IPCC Guidelines. In order to apply this approach 41 trees were cut and a species-specific allometric equation was developed. Considering the aboveground tree biomass, the carbon sink amounts to 1.99 and 1.84 Mg C ha-1 y-1 for the period 1983 - 1994 and 1994 - 2005 respectively. Adding the belowground tree biomass, the estimated sink amounts to 2.59 and 2.39 Mg C ha-1 y-1 for each period. Taking the harvested wood products (firewood, the total carbon sequestration during the second period is 0.16 Mg C ha-1 y-1. The case study highlights the possible rules for the different management strategies. In effect, the utilisation of the entire increase in aboveground biomass as firewood gives an energy substitution effect but, according to the Marrakesh Accords, it cannot be accounted for the KP. On the other hand, an accumulation strategy gives the maximum possible carbon absorption and retention.

  5. Seed Nutrition and Quality, Seed Coat Boron and Lignin Are Influenced by Delayed Harvest in Exotically-Derived Soybean Breeding Lines under High Heat.

    Science.gov (United States)

    Bellaloui, Nacer; Smith, James R; Mengistu, Alemu

    2017-01-01

    The timing of harvest is a major factor affecting seed quality in soybean, particularly in Midsouthern USA, when rain during harvest period is not uncommon. The objective of this research was to evaluate the effects of time of harvest on soybean seed quality (seed composition, germination, seed coat boron, and lignin) in high germinability (HG) breeding lines (50% exotic) developed under high heat. The hypothesis was that seeds of HG lines possess physiological and genetic traits for a better seed quality at harvest maturity and delayed harvest. A 2-year field experiment was conducted under irrigated conditions. Results showed that, at harvest maturity, the exotic HG lines had higher seed protein, oleic acid, sugars, seed coat boron, and seed coat lignin, but lower seed oil compared with the non-exotic checks (Control), confirming our hypothesis. At 28 days after harvest maturity (delayed harvest), the content of seed protein, oleic acid, sugars, seed coat boron, and seed coat lignin were higher in some of the HG lines compared with the checks, indicating a possible involvement of these seed constituents, especially seed coat boron and seed coat lignin, in maintaining seed coat integrity and protecting seed coat against physical damage. Highly significant positive correlations were found between germination and seed protein, oleic acid, sugars, and seed coat boron and seed coat lignin. Highly significant negative correlation was found between germination and oil, linoleic acid, seed coat wrinkling, shattering, and hard seed. Yields of some HG lines were competitive with checks. This research demonstrated that time of harvesting is an important factor influencing seed protein and oil production. Also, since high oleic acid is desirable for oxidative stability, shelf-life and biodiesel properties, using HG lines could positively influence these important traits. This result should suggest to breeders of some of the advantages of selecting for high seed coat boron and

  6. A convenient way to double the capacity of a NEC type foil stripper

    International Nuclear Information System (INIS)

    Chapman, K.R.

    1988-01-01

    A convenient method is described to increase the capacity of a NEC type terminal stripper. This renders the necessity for tank entry to renew foils less frequent. This is especially useful when the use of heavy ion beams renders foil lifetimes very short. (orig.)

  7. Influence and efficiency of catalytic stripper in organic carbon removal from laboratory generated soot aerosols

    Science.gov (United States)

    A catalytic stripper (CS) is a device used to remove the semi-volatile, typically organic carbon, fraction by passing raw or diluted exhaust over an oxidation catalyst heated to 300˚C. The oxidation catalyst used in this study is a commercially available diesel oxidation ca...

  8. 30 CFR 210.155 - What reports must I submit for Federal onshore stripper oil properties?

    Science.gov (United States)

    2010-07-01

    ... Minerals Management Service, P.O. Box 25165, MS 392B2, Denver, Colorado 80217-0165; or (ii) Special courier... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What reports must I submit for Federal onshore stripper oil properties? 210.155 Section 210.155 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT...

  9. Safety evaluation of the ITP filter/stripper test runs and quiet time runs using simulant solution. Revision 3

    International Nuclear Information System (INIS)

    Gupta, M.K.

    1994-06-01

    The purpose is to provide the technical bases for the evaluation of Unreviewed Safety Question for the In-Tank Precipitation (ITP) Filter/Stripper Test Runs (Ref. 7) and Quiet Time Runs Program (described in Section 3.6). The Filter/Stripper Test Runs and Quiet Time Runs program involves a 12,000 gallon feed tank containing an agitator, a 4,000 gallon flush tank, a variable speed pump, associated piping and controls, and equipment within both the Filter and the Stripper Building

  10. High pressure near infrared study of the mutated light-harvesting complex LH2

    Directory of Open Access Journals (Sweden)

    Braun P.

    2005-01-01

    Full Text Available The pressure sensitivities of the near infrared spectra of the light-harvesting (LH2 complex and a mutant complex with a simplified BChl-B850 binding pocket were compared. In the mutant an abrupt change in the spectral properties occurred at 250 MPa, which was not observed with the native sample. Increased disorder due to collapse of the chromophore pocket is suggested.

  11. Optimization Design of an Inductive Energy Harvesting Device for Wireless Power Supply System Overhead High-Voltage Power Lines

    Directory of Open Access Journals (Sweden)

    Wei Wang

    2016-03-01

    Full Text Available Overhead high voltage power line (HVPL online monitoring equipment is playing an increasingly important role in smart grids, but the power supply is an obstacle to such systems’ stable and safe operation, so in this work a hybrid wireless power supply system, integrated with inductive energy harvesting and wireless power transmitting, is proposed. The energy harvesting device extracts energy from the HVPL and transfers that from the power line to monitoring equipment on transmission towers by transmitting and receiving coils, which are in a magnetically coupled resonant configuration. In this paper, the optimization design of online energy harvesting devices is analyzed emphatically by taking both HVPL insulation distance and wireless power supply efficiency into account. It is found that essential parameters contributing to more extracted energy include large core inner radius, core radial thickness, core height and small core gap within the threshold constraints. In addition, there is an optimal secondary coil turn that can maximize extracted energy when other parameters remain fixed. A simple and flexible control strategy is then introduced to limit power fluctuations caused by current variations. The optimization methods are finally verified experimentally.

  12. Vibro-Shock Dynamics Analysis of a Tandem Low Frequency Resonator—High Frequency Piezoelectric Energy Harvester

    Directory of Open Access Journals (Sweden)

    Darius Žižys

    2017-04-01

    Full Text Available Frequency up-conversion is a promising technique for energy harvesting in low frequency environments. In this approach, abundantly available environmental motion energy is absorbed by a Low Frequency Resonator (LFR which transfers it to a high frequency Piezoelectric Vibration Energy Harvester (PVEH via impact or magnetic coupling. As a result, a decaying alternating output signal is produced, that can later be collected using a battery or be transferred directly to the electric load. The paper reports an impact-coupled frequency up-converting tandem setup with different LFR to PVEH natural frequency ratios and varying contact point location along the length of the harvester. RMS power output of different frequency up-converting tandems with optimal resistive values was found from the transient analysis revealing a strong relation between power output and LFR-PVEH natural frequency ratio as well as impact point location. Simulations revealed that higher power output is obtained from a higher natural frequency ratio between LFR and PVEH, an increase of power output by one order of magnitude for a doubled natural frequency ratio and up to 150% difference in power output from different impact point locations. The theoretical results were experimentally verified.

  13. A utility piezoelectric energy harvester with low frequency and high-output voltage: Theoretical model, experimental verification and energy storage

    Directory of Open Access Journals (Sweden)

    Guangyi Zhang

    2016-09-01

    Full Text Available In this paper, a utility piezoelectric energy harvester with low frequency and high-output voltage is presented. Firstly, the harvester’s three theoretical models are presented, namely the static model, the quasi static model and the dynamic vibration model. By analyzing the influence of the mass ratio of the mass block to the beam on output characteristics of the harvester, we compare the quasi static model and the dynamic vibration model and then define their applicable ranges. Secondly, simulation and experiments are done to verify the models, using the harvester with PZT-5H piezoelectric material, which are proved to be consistent with each other. The experimental results show that the output open-circuit voltage and the output power can reach up to 86.36V and 27.5mW respectively. The experiments are conducted when this harvester system is excited by the first modal frequency (58.90Hz with the acceleration 10m/s2. In this low frequency vibration case, it is easy to capture the energy in the daily environment. In addition, LTC 3588-1 chip (Linear Technology Corporation is used as the medium energy circuit to transfer charges from the PZT-5H electrode to the 0.22F 5V super capacitor and ML621 rechargeable button battery. For this super-capacitor, it takes about 100min for the capacitor voltage to rise from 0V to 3.6V. For this button battery, it takes about 200min to increase the battery voltage from 2.5V to 3.48V.

  14. High-performance piezoelectric thick film based energy harvesting micro-generators for MEMS

    DEFF Research Database (Denmark)

    Zawada, Tomasz; Hansen, Karsten; Lou-Moeller, Rasmus

    2010-01-01

    and are transformed by the energy harvesting micro-generator into usable electrical signal. The micro-generator comprises a silicon cantilever with integrated InSensor® TF2100 PZT thick film deposited using screen-printing. The output power versus frequency and electrical load has been investigated. Furthermore......, devices based on modified, pressure treated thick film materials have been tested and compared with the commercial InSensor® TF2100 PZT thick films. It has been found that the structures based on the pressure treated materials exhibit superior properties in terms of energy output....

  15. Evaluation of Over-The-Row Harvester Damage in a Super-High-Density Olive Orchard Using On-Board Sensing Techniques

    Directory of Open Access Journals (Sweden)

    Manuel Pérez-Ruiz

    2018-04-01

    Full Text Available New super-high-density (SHD olive orchards designed for mechanical harvesting using over-the-row harvesters are becoming increasingly common around the world. Some studies regarding olive SHD harvesting have focused on the effective removal of the olive fruits; however, the energy applied to the canopy by the harvesting machine that can result in fruit damage, structural damage or extra stress on the trees has been little studied. Using conventional analyses, this study investigates the effects of different nominal speeds and beating frequencies on the removal efficiency and the potential for fruit damage, and it uses remote sensing to determine changes in the plant structures of two varieties of olive trees (‘Manzanilla Cacereña’ and ‘Manzanilla de Sevilla’ planted in SHD orchards harvested by an over-the-row harvester. ‘Manzanilla de Sevilla’ fruit was the least tolerant to damage, and for this variety, harvesting at the highest nominal speed led to the greatest percentage of fruits with cuts. Different vibration patterns were applied to the olive trees and were evaluated using triaxial accelerometers. The use of two light detection and ranging (LiDAR sensing devices allowed us to evaluate structural changes in the studied olive trees. Before- and after-harvest measurements revealed significant differences in the LiDAR data analysis, particularly at the highest nominal speed. The results of this work show that the operating conditions of the harvester are key to minimising fruit damage and that a rapid estimate of the damage produced by an over-the-row harvester with contactless sensing could provide useful information for automatically adjusting the machine parameters in individual olive groves in the future.

  16. The development of a cryopump for stripper gas pumping in a 30 MV tandem Van de Graaff

    International Nuclear Information System (INIS)

    Halliday, B.S.

    1980-04-01

    The development of a cryopump is described for a 30 MV tandem Van de Graaf accelerator to control the vacuum pressure in the beam tube at the centre terminal when a gas stripper is in use. The system has been fully assembled and has been mechanically tested, the cryo pumps have been cooled to 18 0 K and the insulation tested electrically to +- 20 kV between the pump elements and the biased stripper canal. (UK)

  17. Thermoelectric Energy Harvesting Using Phase Change Materials (PCMs) in High Temperature Environments in Aircraft

    Science.gov (United States)

    Elefsiniotis, A.; Becker, Th.; Schmid, U.

    2014-06-01

    Wireless, energy-autonomous structural health-monitoring systems in aircraft have the potential of reducing total maintenance costs. Thermoelectric energy harvesting, which seems the best choice for creating truly autonomous health monitoring sensors, is the principle behind converting waste heat to useful electrical energy through the use of thermoelectric generators. To enhance the temperature difference across the two sides of a thermoelectric generator, i.e. increasing heat flux and energy production, a phase change material acting as thermal mass is attached on one side of the thermoelectric generators while the other side is placed on the aircraft structure. The application area under investigation for this paper is the pylon aft fairing, located near the engine of an aircraft, with temperatures reaching on the inside up to 350 °C. Given these harsh operational conditions, the performance of a device, containing erythritol as a phase change material, is evaluated. The harvested energy reaching values up to 81.4 J can be regulated by a power management module capable of storing the excess energy and recovering it from the medium powering a sensor node and a wireless transceiver.

  18. Nanofluidic crystal: a facile, high-efficiency and high-power-density scaling up scheme for energy harvesting based on nanofluidic reverse electrodialysis

    International Nuclear Information System (INIS)

    Ouyang Wei; Wang Wei; Zhang Haixia; Wu Wengang; Li Zhihong

    2013-01-01

    The great advances in nanotechnology call for advances in miniaturized power sources for micro/nano-scale systems. Nanofluidic channels have received great attention as promising high-power-density substitutes for ion exchange membranes for use in energy harvesting from ambient ionic concentration gradient, namely reverse electrodialysis. This paper proposes the nanofluidic crystal (NFC), of packed nanoparticles in micro-meter-sized confined space, as a facile, high-efficiency and high-power-density scaling-up scheme for energy harvesting by nanofluidic reverse electrodialysis (NRED). Obtained from the self-assembly of nanoparticles in a micropore, the NFC forms an ion-selective network with enormous nanochannels due to electrical double-layer overlap in the nanoparticle interstices. As a proof-of-concept demonstration, a maximum efficiency of 42.3 ± 1.84%, a maximum power density of 2.82 ± 0.22 W m −2 , and a maximum output power of 1.17 ± 0.09 nW/unit (nearly three orders of magnitude of amplification compared to other NREDs) were achieved in our prototype cell, which was prepared within 30 min. The current NFC-based prototype cell can be parallelized and cascaded to achieve the desired output power and open circuit voltage. This NFC-based scaling-up scheme for energy harvesting based on NRED is promising for the building of self-powered micro/nano-scale systems. (paper)

  19. Surface treatment of glass substrates for the preparation of long-lived carbon stripper foils

    International Nuclear Information System (INIS)

    Takeuchi, Suehiro; Takekoshi, Eiko

    1981-02-01

    Glass substrates having uniformly distributed microscopic grains on the surfaces are useful to make long-lived carbon stripper foils for heavy ions. A method of surface treatment of glass substrates to form the surface structure is described. This method consists of precipitation of glass components, such as soda, onto the surfaces in a hot and humid atmosphere and a fogging treatment of forming microscopic grains of the precipitated substances. Some results of studies on the treatment conditions are also presented. (author)

  20. LOW COST METHODOLOGIES TO ANALYZE AND CORRECT ABNORMAL PRODUCTION DECLINE IN STRIPPER GAS WELLS

    International Nuclear Information System (INIS)

    Jerry James; Gene Huck; Tim Knobloch

    2001-01-01

    A study group of 376 Clinton Sand wells in Ohio provided data to determine the historic frequency of the problem of abnormal production declines in stripper gas wells and the causes of the abnormal production decline. Analysis of the historic frequency of the problem indicates over 70% of the wells experienced abnormal production decline. The most frequently occurring causes of abnormal production declines were determined to be fluid accumulation (46%), gas gathering restrictions (24%), and mechanical failures (23%). Data collection forms and decision trees were developed to cost-effectively diagnose the abnormal production declines and suggest corrective action. The decision trees and data collection sheets were incorporated into a procedure guide to provide stripper gas well operators with a methodology to analyze and correct abnormal production declines. The systematic methodologies and techniques developed should increase the efficiency of problem well assessment and implementation of solutions for stripper gas wells. This eight quarterly technical progress report provides a summary of the deliverables completed to date, including the results of the remediations, the procedure guide, and the technology transfer. Due to the successful results of the study to date and the efficiency of the methodology development, two to three additional wells will be selected for remediation for inclusion into the study. The results of the additional remediations will be included in the final report

  1. Harvest Regulations and Implementation Uncertainty in Small Game Harvest Management

    Directory of Open Access Journals (Sweden)

    Pål F. Moa

    2017-09-01

    Full Text Available A main challenge in harvest management is to set policies that maximize the probability that management goals are met. While the management cycle includes multiple sources of uncertainty, only some of these has received considerable attention. Currently, there is a large gap in our knowledge about implemention of harvest regulations, and to which extent indirect control methods such as harvest regulations are actually able to regulate harvest in accordance with intended management objectives. In this perspective article, we first summarize and discuss hunting regulations currently used in management of grouse species (Tetraonidae in Europe and North America. Management models suggested for grouse are most often based on proportional harvest or threshold harvest principles. These models are all built on theoretical principles for sustainable harvesting, and provide in the end an estimate on a total allowable catch. However, implementation uncertainty is rarely examined in empirical or theoretical harvest studies, and few general findings have been reported. Nevertheless, circumstantial evidence suggest that many of the most popular regulations are acting depensatory so that harvest bag sizes is more limited in years (or areas where game density is high, contrary to general recommendations. A better understanding of the implementation uncertainty related to harvest regulations is crucial in order to establish sustainable management systems. We suggest that scenario tools like Management System Evaluation (MSE should be more frequently used to examine robustness of currently applied harvest regulations to such implementation uncertainty until more empirical evidence is available.

  2. Consortium for Petroleum & Natural Gas Stripper Wells PART 3 OF 3

    Energy Technology Data Exchange (ETDEWEB)

    Morrison, Joel [Pennsylvania State Univ., University Park, PA (United States)

    2011-12-01

    The United States has more oil and gas wells than any other country. As of December 31, 2004, there were more than half a million producing oil wells in the United States. That is more than three times the combined total for the next three leaders: China, Canada, and Russia. The Stripper Well Consortium (SWC) is a partnership that includes domestic oil and gas producers, service and supply companies, trade associations, academia, the Department of Energy’s Strategic Center for Natural Gas and Oil (SCNGO) at the National Energy Technology Laboratory (NETL), and the New York State Energy Research and Development Authority (NYSERDA). The Consortium was established in 2000. This report serves as a final technical report for the SWC activities conducted over the May 1, 2004 to December 1, 2011 timeframe. During this timeframe, the SWC worked with 173 members in 29 states and three international countries, to focus on the development of new technologies to benefit the U.S. stripper well industry. SWC worked with NETL to develop a nationwide request-for-proposal (RFP) process to solicit proposals from the U.S. stripper well industry to develop and/or deploy new technologies that would assist small producers in improving the production performance of their stripper well operations. SWC conducted eight rounds of funding. A total of 132 proposals were received. The proposals were compiled and distributed to an industrydriven SWC executive council and program sponsors for review. Applicants were required to make a formal technical presentation to the SWC membership, executive council, and program sponsors. After reviewing the proposals and listening to the presentations, the executive council made their funding recommendations to program sponsors. A total of 64 projects were selected for funding, of which 59 were fully completed. Penn State then worked with grant awardees to issue a subcontract for their approved work. SWC organized and hosted a total of 14 meetings

  3. Consortium for Petroleum & Natural Gas Stripper Wells PART 2 OF 3

    Energy Technology Data Exchange (ETDEWEB)

    Morrison, Joel [Pennsylvania State Univ., University Park, PA (United States)

    2011-12-01

    The United States has more oil and gas wells than any other country. As of December 31, 2004, there were more than half a million producing oil wells in the United States. That is more than three times the combined total for the next three leaders: China, Canada, and Russia. The Stripper Well Consortium (SWC) is a partnership that includes domestic oil and gas producers, service and supply companies, trade associations, academia, the Department of Energy’s Strategic Center for Natural Gas and Oil (SCNGO) at the National Energy Technology Laboratory (NETL), and the New York State Energy Research and Development Authority (NYSERDA). The Consortium was established in 2000. This report serves as a final technical report for the SWC activities conducted over the May 1, 2004 to December 1, 2011 timeframe. During this timeframe, the SWC worked with 173 members in 29 states and three international countries, to focus on the development of new technologies to benefit the U.S. stripper well industry. SWC worked with NETL to develop a nationwide request-for-proposal (RFP) process to solicit proposals from the U.S. stripper well industry to develop and/or deploy new technologies that would assist small producers in improving the production performance of their stripper well operations. SWC conducted eight rounds of funding. A total of 132 proposals were received. The proposals were compiled and distributed to an industrydriven SWC executive council and program sponsors for review. Applicants were required to make a formal technical presentation to the SWC membership, executive council, and program sponsors. After reviewing the proposals and listening to the presentations, the executive council made their funding recommendations to program sponsors. A total of 64 projects were selected for funding, of which 59 were fully completed. Penn State then worked with grant awardees to issue a subcontract for their approved work. SWC organized and hosted a total of 14 meetings

  4. Broadband Light-Harvesting Molecular Triads with High FRET Efficiency Based on the Coumarin-Rhodamine-BODIPY Platform.

    Science.gov (United States)

    He, Longwei; Zhu, Sasa; Liu, Yong; Xie, Yinan; Xu, Qiuyan; Wei, Haipeng; Lin, Weiying

    2015-08-17

    Broadband capturing and FRET-based light-harvesting molecular triads, CRBs, based on the coumarin-rhodamine-BODIPY platform were rationally designed and synthesized. The absorption band of CRBs starts from blue-green to yellow-orange regions (330-610 nm), covering the strong radiation scope of sunlight. The peripheral coumarin and BODIPY chromophore energy could transfer to the central acceptor rhodamine by a one-step direct way. The energy of the coumarin moiety could also transfer to the BODIPY unit, subsequently transferring to the rhodamine core by two-step sequential ways. Both the efficiencies of the coumarin moiety and the BODIPY unit to the rhodamine core in CRBs, determined by two different ways, are very high. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. High-aspect ratio micro- and nanostructures enabled by photo-electrochemical etching for sensing and energy harvesting applications

    Science.gov (United States)

    Alhalaili, Badriyah; Dryden, Daniel M.; Vidu, Ruxandra; Ghandiparsi, Soroush; Cansizoglu, Hilal; Gao, Yang; Saif Islam, M.

    2018-03-01

    Photo-electrochemical (PEC) etching can produce high-aspect ratio features, such as pillars and holes, with high anisotropy and selectivity, while avoiding the surface and sidewall damage caused by traditional deep reactive ion etching (DRIE) or inductively coupled plasma (ICP) RIE. Plasma-based techniques lead to the formation of dangling bonds, surface traps, carrier leakage paths, and recombination centers. In pursuit of effective PEC etching, we demonstrate an optical system using long wavelength (λ = 975 nm) infra-red (IR) illumination from a high-power laser (1-10 W) to control the PEC etching process in n-type silicon. The silicon wafer surface was patterned with notches through a lithography process and KOH etching. Then, PEC etching was introduced by illuminating the backside of the silicon wafer to enhance depth, resulting in high-aspect ratio structures. The effect of the PEC etching process was optimized by varying light intensities and electrolyte concentrations. This work was focused on determining and optimizing this PEC etching technique on silicon, with the goal of expanding the method to a variety of materials including GaN and SiC that are used in designing optoelectronic and electronic devices, sensors and energy harvesting devices.

  6. Harvest timing and techniques to optimize fiber quality in the Texas High Plains

    Science.gov (United States)

    Production conditions typical to the Texas High Plains region can produce cotton crops with high short fiber and nep content, both of which have a detrimental impact on ring spinning performance. Since Texas now produces nearly 50% of the US cotton crop annually, it is critical that research focuses...

  7. High-performance Sonitopia (Sonic Utopia): Hyper intelligent Material-based Architectural Systems for Acoustic Energy Harvesting

    Science.gov (United States)

    Heidari, F.; Mahdavinejad, M.

    2017-08-01

    The rate of energy consumption in all over the world, based on reliable statistics of international institutions such as the International Energy Agency (IEA) shows significant increase in energy demand in recent years. Periodical recorded data shows a continuous increasing trend in energy consumption especially in developed countries as well as recently emerged developing economies such as China and India. While air pollution and water contamination as results of high consumption of fossil energy resources might be consider as menace to civic ideals such as livability, conviviality and people-oriented cities. In other hand, automobile dependency, cars oriented design and other noisy activities in urban spaces consider as threats to urban life. Thus contemporary urban design and planning concentrates on rethinking about ecology of sound, reorganizing the soundscape of neighborhoods, redesigning the sonic order of urban space. It seems that contemporary architecture and planning trends through soundscape mapping look for sonitopia (Sonic + Utopia) This paper is to propose some interactive hyper intelligent material-based architectural systems for acoustic energy harvesting. The proposed architectural design system may be result in high-performance architecture and planning strategies for future cities. The ultimate aim of research is to develop a comprehensive system for acoustic energy harvesting which cover the aim of noise reduction as well as being in harmony with architectural design. The research methodology is based on a literature review as well as experimental and quasi-experimental strategies according the paradigm of designedly ways of doing and knowing. While architectural design has solution-focused essence in problem-solving process, the proposed systems had better be hyper intelligent rather than predefined procedures. Therefore, the steps of the inference mechanism of the research include: 1- understanding sonic energy and noise potentials as energy

  8. Evidence of a high density population of harvested leopards in a montane environment.

    Science.gov (United States)

    Chase Grey, Julia N; Kent, Vivien T; Hill, Russell A

    2013-01-01

    Populations of large carnivores can persist in mountainous environments following extensive land use change and the conversion of suitable habitat for agriculture and human habitation in lower lying areas of their range. The significance of these populations is poorly understood, however, and little attention has focussed on why certain mountainous areas can hold high densities of large carnivores and what the conservation implications of such populations might be. Here we use the leopard (Panthera pardus) population in the western Soutpansberg Mountains, South Africa, as a model system and show that montane habitats can support high numbers of leopards. Spatially explicit capture-recapture (SECR) analysis recorded the highest density of leopards reported outside of state-protected areas in sub-Saharan Africa. This density represents a temporally high local abundance of leopards and we explore the explanations for this alongside some of the potential conservation implications.

  9. Evidence of a high density population of harvested leopards in a montane environment.

    Directory of Open Access Journals (Sweden)

    Julia N Chase Grey

    Full Text Available Populations of large carnivores can persist in mountainous environments following extensive land use change and the conversion of suitable habitat for agriculture and human habitation in lower lying areas of their range. The significance of these populations is poorly understood, however, and little attention has focussed on why certain mountainous areas can hold high densities of large carnivores and what the conservation implications of such populations might be. Here we use the leopard (Panthera pardus population in the western Soutpansberg Mountains, South Africa, as a model system and show that montane habitats can support high numbers of leopards. Spatially explicit capture-recapture (SECR analysis recorded the highest density of leopards reported outside of state-protected areas in sub-Saharan Africa. This density represents a temporally high local abundance of leopards and we explore the explanations for this alongside some of the potential conservation implications.

  10. Design of broadband multilayer dichroic coating for a high-efficiency solar energy harvesting system.

    Science.gov (United States)

    Jiachen, Wang; Lee, Sang Bae; Lee, Kwanil

    2015-05-20

    We report on the design and performance of a broadband dichroic coating for a solar energy conversion system. As a spectral beam splitter, the coating facilitates a hybrid system that combines a photovoltaic cell with a thermal collector. When positioned at a 45° angle with respect to incident light, the coating provides high reflectance in the 40-1100 nm and high transmission in the 1200-2000 nm ranges for a photovoltaic cell and a thermal collector, respectively. Numerical simulations show that our design leads to a sharp transition between the reflection and transmission bands, low ripples in both bands, and slight polarization dependence.

  11. Illustrating harvest effects on site microclimate in a high-elevation forest stand.

    Science.gov (United States)

    W.B. Fowler; T.D. Anderson

    1987-01-01

    Three-dimensional contour surfaces were drawn for physiologically active radiation (PAR) and air and soil temperatures from measurements taken at a high-elevation site (1450 m) near the crest of the Cascade Range in central Washington. Measurements in a clearcut were compared with measurements from an adjacent uncut stand. Data for 31 days in July and August 1985...

  12. Scalable high-performance algorithm for the simulation of exciton-dynamics. Application to the light harvesting complex II in the presence of resonant vibrational modes

    DEFF Research Database (Denmark)

    Kreisbeck, Christoph; Kramer, Tobias; Aspuru-Guzik, Alán

    2014-01-01

    high-performance many-core platforms using the Open Compute Language (OpenCL). For the light-harvesting complex II (LHC II) found in spinach, the HEOM results deviate from predictions of approximate theories and clarify the time-scale of the transfer-process. We investigate the impact of resonantly...

  13. Rotating-Sleeve Triboelectric-Electromagnetic Hybrid Nanogenerator for High Efficiency of Harvesting Mechanical Energy.

    Science.gov (United States)

    Cao, Ran; Zhou, Tao; Wang, Bin; Yin, Yingying; Yuan, Zuqing; Li, Congju; Wang, Zhong Lin

    2017-08-22

    Currently, a triboelectric nanogenerator (TENG) and an electromagnetic generator (EMG) have been hybridized to effectively scavenge mechanical energy. However, one critical issue of the hybrid device is the limited output power due to the mismatched output impedance between the two generators. In this work, impedance matching between the TENG and EMG is achieved facilely through commercial transformers, and we put forward a highly integrated hybrid device. The rotating-sleeve triboelectric-electromagnetic hybrid nanogenerator (RSHG) is designed by simulating the structure of a common EMG, which ensures a high efficiency in transferring ambient mechanical energy into electric power. The RSHG presents an excellent performance with a short-circuit current of 1 mA and open-circuit voltage of 48 V at a rotation speed of 250 rpm. Systematic measurements demonstrate that the hybrid nanogenerator can deliver the largest output power of 13 mW at a loading resistance of 8 kΩ. Moreover, it is demonstrated that a wind-driven RSHG can light dozens of light-emitting diodes and power an electric watch. The distinctive structure and high output performance promise the practical application of this rotating-sleeve structured hybrid nanogenerator for large-scale energy conversion.

  14. High salinity relay as a post-harvest processing method for reducing Vibrio vulnificus levels in oysters (Crassostrea virginica).

    Science.gov (United States)

    Audemard, Corinne; Kator, Howard I; Reece, Kimberly S

    2018-08-20

    High salinity relay of Eastern oysters (Crassostrea virginica) was evaluated as a post-harvest processing (PHP) method for reducing Vibrio vulnificus. This approach relies on the exposure of oysters to natural high salinity waters and preserves a live product compared to previously approved PHPs. Although results of prior studies evaluating high salinity relay as a means to decrease V. vulnificus levels were promising, validation of this method as a PHP following approved guidelines is required. This study was designed to provide data for validation of this method following Food and Drug Administration (FDA) PHP validation guidelines. During each of 3 relay experiments, oysters cultured from 3 different Chesapeake Bay sites of contrasting salinities (10-21 psu) were relayed without acclimation to high salinity waters (31-33 psu) for up to 28 days. Densities of V. vulnificus and densities of total and pathogenic Vibrio parahaemolyticus (as tdh positive strains) were measured using an MPN-quantitative PCR approach. Overall, 9 lots of oysters were relayed with 6 exhibiting initial V. vulnificus >10,000/g. As recommended by the FDA PHP validation guidelines, these lots reached both the 3.52 log reduction and the levels ranged from 2 to 61% after 28 days of relay. Although the identification of the factors implicated in oyster mortality will require further examination, this study strongly supports the validation of high salinity relay as an effective PHP method to reduce levels of V. vulnificus in oysters to endpoint levels approved for human consumption. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Non-contact image processing for gin trash sensors in stripper harvested cotton with burr and fine trash correction

    Science.gov (United States)

    This study was initiated to provide the basis for obtaining online information as to the levels of the various types of gin trash. The objective is to provide the ginner with knowledge of the quantity of the various trash components in the raw uncleaned seed cotton. This information is currently not...

  16. Combine Harvester Simulator

    DEFF Research Database (Denmark)

    Vilmann, Ole; Sørlie, James Arnold

    1999-01-01

    A simulator for training pilots in the operation of a modern high-tech combine harvester is presented. The new simulator application is based on DMI´s well-known DMS maritime simulator architecture. Two major challenges have been encountered in the development of the simulator: 1) interfacing the...

  17. Plataformas de colheita e colheita manual com trilha mecânica sobre a qualidade de sementes de arroz ( Oryza sativa, L. Harvest header and manual harvest with mechanical strip on rice ( Oryza sativa, L. seeds quality

    Directory of Open Access Journals (Sweden)

    Daniel Fernandez Franco

    1999-06-01

    Full Text Available Durante a colheita do arroz irrigado ocorrem perdas e danos físicos e fisiológicos às sementes. No final da década de oitenta, surgiram as plataformas recolhedoras, que retiram ou arrancam o grão ao invés de cortar a panícula, porém, pouco se conhece a respeito dos danos físicos e fisiológicos que este sistema de plataforma pode causar às sementes. Este trabalho teve por objetivo avaliar os danos mecânicos causados às sementes dos cultivares de arroz BR-IRGA 409 e BR-IRGA 410, por três formas de colheita: (a colheita manual e trilha mecânica; (b colheita com plataforma de corte; (c colheita com plataforma recolhedora. Quando a colheita foi mecânica, realizou-se a coleta das amostras diretamente no graneleiro. O delineamento experimental foi blocos ao acaso, com seis repetições. Os resultados demonstraram que as sementes de arroz irrigado dos cultivares estudados não apresentaram diferenças significativas em suas qualidades físicas e fisiológicas, quando colhidas com plataforma de corte e com a plataforma recolhedora. Estes dois métodos de colheita, porém, apresentaram danos significativamente maiores quando comparados à colheita manual e trilha mecânica.During irrigated rice harvesting occur losses and physical and phisiological seed damage. Late 80's, appeared the strippers headers that strip the grain, instead of cutting the spike. However, little is know about physical and phisiological seed damage by harvest header. The objective of this work was to evaluate the mechanical damage caused to BR-IRGA 409 and BR-IRGA 410 rice cultivars by three harvesting methods: (a manual harvesting and mechanical strip; (b cutterbar harvesting and; (c stripper header harvesting. Samples were collected directly in the grain tank when the harvest was mechanical. The experimental design was randomized blocks with six replications. Results demonstrated that the rice seeds of the studied variety didn't showed significant differences in

  18. Treatability test of a stacked-tray air stripper for VOC in water

    Energy Technology Data Exchange (ETDEWEB)

    Pico, T., LLNL

    1998-04-01

    A common strategy for hydraulic containment and mass removal at VOC contaminated sites is `pump and treat (P&T)`. In P&T operations, contaminated ground water is pumped from wells, treated above ground, and discharged. Many P&T remediation systems at VOC sites rely on air stripping technology because VOCs are easily transferred to the vapor phase. In stacked-tray air strippers, contaminated water is aerated while it flows down through a series of trays. System operations at LLNL are strictly regulated by the California and federal Environmental Protection Agencies (Cal/EPA and EPA), the Bay Area Air Quality Management District (BAAQMD), the California Regional Water Quality Control Board (RWQCB) and the Department of Toxic Substances Control (DTSC). These agencies set discharge limits, require performance monitoring, and assess penalties for non-compliance. National laboratories are also subject to scrutiny by the public and other government agencies. This extensive oversight makes it necessary to accurately predict field treatment performance at new extraction locations to ensure compliance with all requirements prior to facility activation. This paper presents treatability test results for a stacked- tray air stripper conducted at LLNL and compares them to the vendor`s modeling software results.

  19. Stripper foil failure modes and cures at the Oak Ridge Spallation Neutron Source

    Directory of Open Access Journals (Sweden)

    M. A. Plum

    2011-03-01

    Full Text Available The Oak Ridge Spallation Neutron Source comprises a 1 GeV, 1.5 MW linear accelerator followed by an accumulator ring and a liquid mercury target. To manage the beam loss caused by the H^{0} excited states created during the H^{-} charge-exchange injection into the accumulator ring, the stripper foil is located inside one of the chicane dipoles. This has some interesting consequences that were not fully appreciated until the beam power reached about 840 kW. One consequence was sudden failure of the stripper foil system due to convoy electrons stripped from the incoming H^{-} beam, which circled around to strike the foil bracket and cause bracket failure. Another consequence is that convoy electrons can reflect back up from the electron catcher and strike the foil and bracket. An additional contributor to foil system failure is vacuum breakdown due to the charge developed on the foil by secondary electron emission. In this paper we detail these and other interesting failure mechanisms and describe the improvements we have made to mitigate them.

  20. A high-efficiency low-voltage CMOS rectifier for harvesting energy in implantable devices.

    Science.gov (United States)

    Hashemi, S Saeid; Sawan, Mohamad; Savaria, Yvon

    2012-08-01

    We present, in this paper, a new full-wave CMOS rectifier dedicated for wirelessly-powered low-voltage biomedical implants. It uses bootstrapped capacitors to reduce the effective threshold voltage of selected MOS switches. It achieves a significant increase in its overall power efficiency and low voltage-drop. Therefore, the rectifier is good for applications with low-voltage power supplies and large load current. The rectifier topology does not require complex circuit design. The highest voltages available in the circuit are used to drive the gates of selected transistors in order to reduce leakage current and to lower their channel on-resistance, while having high transconductance. The proposed rectifier was fabricated using the standard TSMC 0.18 μm CMOS process. When connected to a sinusoidal source of 3.3 V peak amplitude, it allows improving the overall power efficiency by 11% compared to the best recently published results given by a gate cross-coupled-based structure.

  1. From Digital Commons to OCLC: A Tailored Approach for Harvesting and Transforming ETD Metadata into High-Quality Records

    Directory of Open Access Journals (Sweden)

    Marielle Veve

    2016-07-01

    Full Text Available The library literature contains many examples of automated and semi-automated approaches to harvest electronic theses and dissertations (ETD metadata from institutional repositories (IR to the Online Computer Library Center (OCLC. However, most of these approaches could not be implemented with the institutional repository software Digital Commons because of various reasons including proprietary schema incompatibilities and high level programming expertise requirements our institution did not want to pursue. Only one semi-automated approach was found in the library literature which met our requirements for implementation, and even though it catered to the particular needs of the DSpace IR, it could be implemented to other IR software if further customizations were applied. The following paper presents an extension of this semi-automated approach originally created by Deng and Reese, but customized and adapted to address the particular needs of the Digital Commons community and updated to integrate the latest Resource Description & Access (RDA content standards for ETDs. Advantages and disadvantages of this workflow are discussed and presented as well.

  2. Nerium oleander indirect leaf photosynthesis and light harvesting reductions after clipping injury or Spodoptera eridania herbivory: high sensitivity to injury.

    Science.gov (United States)

    Delaney, Kevin J

    2012-04-01

    Variable indirect photosynthetic rate (P(n)) responses occur on injured leaves after insect herbivory. It is important to understand factors that influence indirect P(n) reductions after injury. The current study examines the relationship between gas exchange and chlorophyll a fluorescence parameters with injury intensity (% single leaf tissue removal) from clipping or Spodoptera eridania Stoll (Noctuidae) herbivory on Nerium oleander L. (Apocynaceae). Two experiments showed intercellular [CO(2)] increases but P(n) and stomatal conductance reductions with increasing injury intensity, suggesting non-stomatal P(n) limitation. Also, P(n) recovery was incomplete at 3d post-injury. This is the first report of a negative exponential P(n) impairment function with leaf injury intensity to suggest high N. oleander leaf sensitivity to indirect P(n) impairment. Negative linear functions occurred between most other gas exchange and chlorophyll a fluorescence parameters with injury intensity. The degree of light harvesting impairment increased with injury intensity via lower (1) photochemical efficiency indicated lower energy transfer efficiency from reaction centers to PSII, (2) photochemical quenching indicated reaction center closure, and (3) electron transport rates indicated less energy traveling through PSII. Future studies can examine additional mechanisms (mesophyll conductance, carbon fixation, and cardenolide induction) to cause N. oleander indirect leaf P(n) reductions after injury. Published by Elsevier Ireland Ltd.

  3. Microalgae harvesting techniques: A review.

    Science.gov (United States)

    Singh, Gulab; Patidar, S K

    2018-07-01

    Microalgae with wide range of commercial applications have attracted a lot of attention of the researchers in the last few decades. However, microalgae utilization is not economically sustainable due to high cost of harvesting. A wide range of solid - liquid separation techniques are available for microalgae harvesting. The techniques include coagulation and flocculation, flotation, centrifugation and filtration or a combination of various techniques. Despite the importance of harvesting to the economics and energy balance, there is no universal harvesting technique for microalgae. Therefore, this review focuses on assessing technical, economical and application potential of various harvesting techniques so as to allow selection of an appropriate technology for cost effectively harvesting of microalgae from their culture medium. Various harvesting and concentrating techniques of microalgae were reviewed to suggest order of suitability of the techniques for four main microalgae applications i.e biofuel, human and animal food, high valued products, and water quality restoration. For deciding the order of suitability, a comparative analysis of various harvesting techniques based on the six common criterions (i.e biomass quality, cost, biomass quantity, processing time, species specific and toxicity) has been done. Based on the order of various techniques vis-a-vis various criteria and preferred order of criteria for various applications, order of suitability of harvesting techniques for various applications has been decided. Among various harvesting techniques, coagulation and flocculation, centrifugation and filtration were found to be most suitable for considered applications. These techniques may be used alone or in combination for increasing the harvesting efficiency. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Tandem accelerator transmission and life measurement of 50 keV/amu Au ions using stripper foil made by INS

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, Satoshi; Takahashi, Tsutomu; Shima, Kunihiro [Tsukuba Univ., Ibaraki (Japan). Tandem Accelerator Center; Sugai, Isamu; Oyaizu, Mitsuhiro

    1996-12-01

    The role of stripper foil is the charge exchange of ions. The thickness for attaining equilibrium in charge exchange becomes thinner as ions become lower speed and heavier. Accordingly, for the stripper foil, thin foil thickness is demanded in addition to the demand of long life. The stripper foil made by INS, University of Tokyo, is recognized as its long life. In the 12 UD PELETRON tandem accelerator in University of Tsukuba, in order to meet the demand of users to use heavy ions, the use of long life stripper foil has become urgent necessity. Therefore, as for the foil made by INS, the life by Au ion irradiation and the Au ion transmission were measured four times. As to the features of the test of this time, irradiation was carried out under the severe condition for the foil of low speed Au ions, and the change of beam transmission with time lapse was observed in addition to the life. The method of measurement is explained. The preparation of foils and the determination of their thickness are reported. As the results, the lifetime of the foils made by INS and the thickness dependence and time dependence or dose dependence of the transmission of low speed, heavy Au-197 ions are described. (K.I.)

  5. 75 FR 61624 - Promotion of Development, Reduction of Royalty Rates for Stripper Well and Heavy Oil Properties

    Science.gov (United States)

    2010-10-06

    ...-241A.00] RIN 1004-AE04 Promotion of Development, Reduction of Royalty Rates for Stripper Well and Heavy... economy, productivity, competition, jobs, the environment, public health or safety, or State, local, or..., investment, productivity, innovation, or the ability of U.S.-based enterprises to compete with foreign-based...

  6. Energy harvesting for microsystems

    Energy Technology Data Exchange (ETDEWEB)

    Ruichao Xu

    2012-05-15

    The purpose of this project is to design and fabricate piezoelectric energy harvesters based on integration of Pb(ZrxTi1-x)O3 (PZT) thick film technology and silicon microtechnology. The fabrication processes are carried out in close collaboration with Meggitt Sensing Systems (MSS) who has the unique expertise to screen print piezoelectric thick film layers, thus all screen printing steps are done by MSS while the silicon micromachining is carried out at Danchip facility at DTU. The presented energy harvesters are all based on using piezoelectric thick film operating in the 31-mode to generate power when strained. Three archetypes of the numerous fabricated energy harvesters will be presented in detail, they represent three major milestones in this project. The first energy harvester archetype has an unimorph cantilever beam, which consists of a 20 {mu}m silicon layer and 10-30 {mu}m screen printed PZT layer, anchored on a silicon frame at one end and attached to a silicon proof mass at the other. Electrodes will cover both side of the PZT layer, so the harvested energy can be collected electrically. The second archetype has a bimorph cantilever beam, which consists of two 15-35 {mu}m PZT layers, anchored on a silicon frame at the one end and attached to a silicon proof mass at the other. Electrodes are deposited below, between and above the two PZT layers. The root mean square (RMS) power output measured on this type of harvesters is as high as 37.1{mu}W at 1 g. The third archetype is similar to the first one, the screen printed PZT layer is replaced by a lead free piezoelectric material, (KxNa1-x)NbO3 (KNN). Some of the major challenges encountered during the development processes are bad adhesion, fragile structures and short circuiting through the PZT layer. All of which have being fully or partially solved in this project. The final energy harvesters are designed to be used in an energy harvester powered wireless sensing system. (Author)

  7. Experimental verificatio of load resistance switching for global stabilization of high-energy response of a nonlinear wideband electromagnetic vibration energy harvester

    International Nuclear Information System (INIS)

    Sato, T; Masuda, A; Sanada, T

    2015-01-01

    This paper presents an experimental verification of a self-excitation control of a resonance- type vibration energy harvester with a Duffing-type nonlinearity which is designed to perform effectively in a wide frequency range. For the conventional linear vibration energy harvester, the performance of the power generation at the resonance frequency and the bandwidth of the resonance peak are trade-off. The resonance frequency band can be expanded by introducing a Duffing-type nonlinear oscillator in order to enable the harvester to generate larger electric power in a wider frequency range. However, since such nonlinear oscillator can have multiple stable steady-state solutions in the resonance band, it is difficult for the nonlinear harvester to maintain the high performance of the power generation constantly. The principle of self-excitation and entrainment has been utilized to provide the global stability to the highest-energy solution by destabilizing other unexpected lower-energy solutions by introducing a switching circuit of the load resistance between positive and the negative values depending on the response amplitude of the oscillator. It has been experimentally validated that this control law imparts the self-excitation capability to the oscillator to show an entrainment into the highest-energy solution. (paper)

  8. Modelling Accumulator Stripper Foil Heating for ESSNUSB Facility

    CERN Document Server

    Martini, Michel

    2015-01-01

    It is proposed to use the 2.0 GeV, 5 MW proton linac, 2.86 ms long pulses at 14 Hz of the European Spallation Source [1], [2] being built in Lund, Sweden to deliver, alternately with the spallation neutron production a very intense neutrino beam to enable the discovery of leptonic CP violation. To this end the linac would be upgraded to supply, in addition to the 2.86 ms long proton pulses at 14 Hz, four 0.72 ms H short pulses at 70 Hz for neutrino production. Because of the high current required in the pulsed neutrino horn, the length of the pulses used for neutrino production will need to be compressed to a few s with the aid of an accumulator ring. Charge exchange injection of an H- beam from the linac will be used, the linac delivering 1.1E15 H- per pulse. This paper is about stripping foil heating considerations, emphasizing the detailed evaluation of the foil temperature over the multiple ring re-fills

  9. Highly efficient energy transfer from a carbonyl carotenoid to chlorophyll a in the main light harvesting complex of Chromera velia.

    Science.gov (United States)

    Durchan, Milan; Keşan, Gürkan; Slouf, Václav; Fuciman, Marcel; Staleva, Hristina; Tichý, Josef; Litvín, Radek; Bína, David; Vácha, František; Polívka, Tomáš

    2014-10-01

    We report on energy transfer pathways in the main light-harvesting complex of photosynthetic relative of apicomplexan parasites, Chromera velia. This complex, denoted CLH, belongs to the family of FCP proteins and contains chlorophyll (Chl) a, violaxanthin, and the so far unidentified carbonyl carotenoid related to isofucoxanthin. The overall carotenoid-to-Chl-a energy transfer exhibits efficiency over 90% which is the largest among the FCP-like proteins studied so far. Three spectroscopically different isofucoxanthin-like molecules were identified in CLH, each having slightly different energy transfer efficiency that increases from isofucoxanthin-like molecules absorbing in the blue part of the spectrum to those absorbing in the reddest part of spectrum. Part of the energy transfer from carotenoids proceeds via the ultrafast S2 channel of both the violaxanthin and isofucoxanthin-like carotenoid, but major energy transfer pathway proceeds via the S1/ICT state of the isofucoxanthin-like carotenoid. Two S1/ICT-mediated channels characterized by time constants of ~0.5 and ~4ps were found. For the isofucoxanthin-like carotenoid excited at 480nm the slower channel dominates, while those excited at 540nm employs predominantly the fast 0.5ps channel. Comparing these data with the excited-state properties of the isofucoxanthin-like carotenoid in solution we conclude that, contrary to other members of the FCP family employing carbonyl carotenoids, CLH complex suppresses the charge transfer character of the S1/ICT state of the isofucoxanthin-like carotenoid to achieve the high carotenoid-to-Chl-a energy transfer efficiency. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. SELECTION AND TREATMENT OF STRIPPER GAS WELLS FOR PRODUCTION ENHANCEMENT, MOCANE-LAVERNE FIELD, OKLAHOMA

    Energy Technology Data Exchange (ETDEWEB)

    Scott Reeves; Buckley Walsh

    2003-08-01

    In 1996, Advanced Resources International (ARI) began performing R&D targeted at enhancing production and reserves from natural gas fields. The impetus for the effort was a series of field R&D projects in the early-to-mid 1990's, in eastern coalbed methane and gas shales plays, where well remediation and production enhancement had been successfully demonstrated. As a first step in the R&D effort, an assessment was made of the potential for restimulation to provide meaningful reserve additions to the U.S. gas resource base, and what technologies were needed to do so. That work concluded that: (1) A significant resource base did exist via restimulation (multiples of Tcf). (2) The greatest opportunities existed in non-conventional plays where completion practices were (relatively) complex and technology advancement was rapid. (3) Accurate candidate selection is the greatest single factor that contributes to a successful restimulation program. With these findings, a field-oriented program targeted at tight sand formations was initiated to develop and demonstrate successful candidate recognition technology. In that program, which concluded in 2001, nine wells were restimulated in the Green River, Piceance and East Texas basins, which in total added 2.9 Bcf of reserves at an average cost of $0.26/Mcf. In addition, it was found that in complex and heterogeneous reservoirs (such as tight sand formations), candidate selection procedures should involve a combination of fundamental engineering and advanced pattern recognition approaches, and that simple statistical methods for identifying candidate wells are not effective. In mid-2000, the U.S. Department of Energy (DOE) awarded ARI an R&D contract to determine if the methods employed in that project could also be applied to stripper gas wells. In addition, the ability of those approaches to identify more general production enhancement opportunities (beyond only restimulation), such as via artificial lift and compression

  11. Highly efficient energy transfer from a carbonyl carotenoid to chlorophyll a in the main light harvesting complex of Chromera velia

    Czech Academy of Sciences Publication Activity Database

    Durchan, Milan; Kesan, G.; Šlouf, M.; Fuciman, M.; Staleva, H.; Tichý, Josef; Litvín, Radek; Bína, David; Vácha, František; Polívka, Tomáš

    2014-01-01

    Roč. 1837, č. 10 (2014), s. 1748-1755 ISSN 0005-2728 R&D Projects: GA ČR(CZ) GAP205/11/1164; GA ČR GBP501/12/G055 Institutional support: RVO:60077344 Keywords : Energy transfer * Light-harvesting * Carbonyl carotenoids Subject RIV: BO - Biophysics Impact factor: 5.353, year: 2014

  12. Investigations on KONUS beam dynamics using the pre-stripper drift tube linac at GSI

    Science.gov (United States)

    Xiao, C.; Du, X. N.; Groening, L.

    2018-04-01

    Interdigital H-mode (IH) drift tube linacs (DTLs) based on KONUS beam dynamics are very sensitive to the rf-phases and voltages at the gaps between tubes. In order to design these DTLs, a deep understanding of the underlying longitudinal beam dynamics is mandatory. The report presents tracking simulations along an IH-DTL using the PARTRAN and BEAMPATH codes together with MATHCAD and CST. Simulation results illustrate that the beam dynamics design of the pre-stripper IH-DTL at GSI is sensitive to slight deviations of rf-phase and gap voltages with impact to the mean beam energy at the DTL exit. Applying the existing geometrical design, rf-voltages, and rf-phases of the DTL were re-adjusted. In simulations this re-optimized design can provide for more than 90% of transmission of an intense 15 emA beam keeping the reduction of beam brilliance below 25%.

  13. High Harvest Yield, High Expansion, and Phenotype Stability of CD146 Mesenchymal Stromal Cells from Whole Primitive Human Umbilical Cord Tissue

    Directory of Open Access Journals (Sweden)

    Rebecca C. Schugar

    2009-01-01

    Full Text Available Human umbilical cord blood is an excellent primitive source of noncontroversial stem cells for treatment of hematologic disorders; meanwhile, new stem cell candidates in the umbilical cord (UC tissue could provide therapeutic cells for nonhematologic disorders. We show novel in situ characterization to identify and localize a panel of some markers expressed by mesenchymal stromal cells (MSCs; CD44, CD105, CD73, CD90 and CD146 in the UC. We describe enzymatic isolation and purification methods of different UC cell populations that do not require manual separation of the vessels and stroma of the coiled, helical-like UC tissue. Unique quantitation of in situ cell frequency and stromal cell counts upon harvest illustrate the potential to obtain high numerical yields with these methods. UC stromal cells can differentiate to the osteogenic and chondrogenic lineages and, under specific culturing conditions, they exhibit high expandability with unique long-term stability of their phenotype. The remarkable stability of the phenotype represents a novel finding for human MSCs, from any source, and supports the use of these cells as highly accessible stromal cells for both basic studies and potentially therapeutic applications such as allogeneic clinical use for musculoskeletal disorders.

  14. Harvesting the free fibular graft: A modified approach

    Directory of Open Access Journals (Sweden)

    Amitava Narayan Mukherjee

    2011-01-01

    Full Text Available Background: The conventional technique of free non-vascularized fibular grafting is attended with some amount of morbidity and a long scar. We report a technique with little interference to the surrounding soft tissues to harvest more than one-third of whole length fibula. Patients and Methods: Thirty four patients of average age 23.5 years (range 8 to 51 years having various pathologies like simple bone cysts (n=9, fibrous dysplasias (n=6, giant cell tumors (n=7, fracture non-union (n=10 and aneurysmal bone cysts (n=2 were taken up for the study. The fibula were harvested by two separate incisions, 1 cm each at proximal and distal extent of proposed donor site for taking out of graft after elevating the periosteum circumferentially using a periosteum stripper. Compression bandage and above knee plaster immobilization was applied to reduce the dead space collection . Results: The mean followup is 34 months. The patients were evaluated clinicoradiology. Thirty three patients showed good results. One patient had fair result due to delayed wound healing from hematoma which was treated surgically. Conclusion: The approach of harvesting fibula suggested by author reduces donor site morbidity and is safer than conventional approach.

  15. Subtle spectral effects accompanying the assembly of bacteriochlorophylls into cyclic light harvesting complexes revealed by high-resolution fluorescence spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Rätsep, Margus, E-mail: margus.ratsep@ut.ee; Pajusalu, Mihkel, E-mail: mihkel.pajusalu@ut.ee; Linnanto, Juha Matti, E-mail: juha.matti.linnanto@ut.ee [Institute of Physics, University of Tartu, Riia 142, 51014 Tartu (Estonia); Freiberg, Arvi, E-mail: arvi.freiberg@ut.ee [Institute of Physics, University of Tartu, Riia 142, 51014 Tartu, Estonia and Institute of Molecular and Cell Biology, University of Tartu, Riia 23, 51010 Tartu (Estonia)

    2014-10-21

    We have observed that an assembly of the bacteriochloropyll a molecules into B850 and B875 groups of cyclic bacterial light-harvesting complexes LH2 and LH1, respectively, results an almost total loss of the intra-molecular vibronic structure in the fluorescence spectrum, and simultaneously, an essential enhancement of its phonon sideband due to electron-phonon coupling. While the suppression of the vibronic coupling in delocalized (excitonic) molecular systems is predictable, as also confirmed by our model calculations, a boost of the electron-phonon coupling is rather unexpected. The latter phenomenon is explained by exciton self-trapping, promoted by mixing the molecular exciton states with charge transfer states between the adjacent chromophores in the tightly packed B850 and B875 arrangements. Similar, although less dramatic trends were noted for the light-harvesting complexes containing chlorophyll pigments.

  16. ESTABLISHMENT OF AN INDUSTRY-DRIVEN CONSORTIUM FOCUSED ON IMPROVING THE PRODUCTION PERFORMANCE OF DOMESTIC STRIPPER WELLS

    International Nuclear Information System (INIS)

    Joel L. Morrison

    2001-01-01

    The Pennsylvania State University, under contract to the US Department of Energy, National Energy Technology Laboratory will establish, promote, and manage a national industry-driven Stripper Well Consortium (SWC) that will be focused on improving the production performance of domestic petroleum and/or natural gas stripper wells. the consortium creates a partnership with the US petroleum and natural gas industries and trade associations, state funding agencies, academia, and the National Energy Technology Laboratory. This report serves as the third quarterly technical progress report for the SWC. During this reporting period the SWC entered into a co-funding arrangement with the New York State Energy Development Authority (NYSERDA) to provide an additional$100,000 in co-funding for stripper well production-orientated projects.The SWC hosted its first meeting in which members proposed research projects to the SWC membership. The meeting was held on April 9-10, 2001 in State College, Pennsylvania. Twenty three proposals were submitted to the SWC for funding consideration. Investigators of the proposed projects provided the SWC membership with a 20 minute (15 minute technical discussion, 5 minute question and answer session) presentation. Of the 23 proposals, the Executive Council approved$921,000 in funding for 13 projects. Penn State then immediately started the process of issuing subcontracts to the various projects approved for funding

  17. ESTABLISHMENT OF AN INDUSTRY-DRIVEN CONSORTIUM FOCUSED ON IMPROVING THE PRODUCTION PERFORMANCE OF DOMESTIC STRIPPER WELLS

    Energy Technology Data Exchange (ETDEWEB)

    Joel L. Morrison

    2001-09-12

    The Pennsylvania State University, under contract to the US Department of Energy, National Energy Technology Laboratory will establish, promote, and manage a national industry-driven Stripper Well Consortium (SWC) that will be focused on improving the production performance of domestic petroleum and/or natural gas stripper wells. the consortium creates a partnership with the US petroleum and natural gas industries and trade associations, state funding agencies, academia, and the National Energy Technology Laboratory. This report serves as the third quarterly technical progress report for the SWC. During this reporting period the SWC entered into a co-funding arrangement with the New York State Energy Development Authority (NYSERDA) to provide an additional $100,000 in co-funding for stripper well production-orientated projects.The SWC hosted its first meeting in which members proposed research projects to the SWC membership. The meeting was held on April 9-10, 2001 in State College, Pennsylvania. Twenty three proposals were submitted to the SWC for funding consideration. Investigators of the proposed projects provided the SWC membership with a 20 minute (15 minute technical discussion, 5 minute question and answer session) presentation. Of the 23 proposals, the Executive Council approved $921,000 in funding for 13 projects. Penn State then immediately started the process of issuing subcontracts to the various projects approved for funding.

  18. Development of a High-performance Fluorpolymer Electret Mixed with Nano-particles and Its Application to Vibration Energy Harvesting

    International Nuclear Information System (INIS)

    Suzuki, M; Takahashi, T; Aoyagi, S

    2014-01-01

    We have been developing small power generation device of capacitance-type to be converted to electrical energy vibration energy using an electret. In this Study, dielectric nanoparticles were mixed with an electret made of fluorocarbon polymer. As a result, implanted charge density of the electret was successfully enhanced thanks to the mixing of particles. A small sized vibration energy harvester (VEH) was fabricated using the fluorocarbon mixed with dielectric nano-particles. As a result of applying vibration (20 Hz, 0.65 G) to the fabricated VEH, The maximum generated power of approximately 50 μW was obtained

  19. Highly durable piezo-electric energy harvester by a super toughened and flexible nanocomposite: effect of laponite nano-clay in poly(vinylidene fluoride)

    Science.gov (United States)

    Rahman, Wahida; Ghosh, Sujoy Kumar; Ranjan Middya, Tapas; Mandal, Dipankar

    2017-09-01

    A highly durable piezoelectric energy harvester is introduced by integrating the toughness and flexibility of a non-electrically poled, laponite nano-clay mineral-induced γ-phase (up to 98%) in a poly(vinylidene-fluoride) (PVDF) matrix by a simple solvent evaporation technique. Owing to a superior electromechanical coupling effect, PVDF/laponite nanocomposites retain excellent biomechanical energy harvesting capabilities under external vibration (as high as 6 V output voltage and 70 nA output current under a compressive force of 300 N) and charge storage properties under an external high electric field (maximum 0.8~ \\text{J} \\text{c}{{\\text{m}}-3} of discharged energy density at a breakdown strength of 302 MV m-1). As a proof of concept, the fabricated nanogenerator (NG) possesses a high output power density (~6.3 mW m-2) that directly drives several consumer electronics without using any storage system or batteries. It paves the way for potential applicability in next generation electronics, particularly as a self-powered device and to configure sustainable internet of things (IoT) sensor networks.

  20. Wideband Electrostatic Vibration Energy Harvester (e-VEH) Having a Low Start-Up Voltage Employing a High-Voltage Integrated Interface

    International Nuclear Information System (INIS)

    Dudka, A; Galayko, D; Basset, P; Cottone, F; Blokhina, E

    2013-01-01

    This paper reports on an electrostatic Vibration Energy Harvester (e-VEH) system, for which the energy conversion process is initiated with a low bias voltage and is compatible with wideband stochastic external vibrations. The system employs the auto-synchronous conditioning circuit topology with the use of a novel dedicated integrated low-power high-voltage switch that is needed to connect the charge pump and flyback – two main parts of the used conditioning circuit. The proposed switch is designed and implemented in AMS035HV CMOS technology. Thanks to the proposed switch device, which is driven with a low-voltage ground-referenced logic, the e-VEH system may operate within a large voltage range, from a pre-charge low voltage up to several tens volts. With such a high-voltage e-VEH operation, it is possible to obtain a strong mechanical coupling and a high rate of vibration energy conversion. The used transducer/resonator device is fabricated with a batch-processed MEMS technology. When excited with stochastic vibrations having an acceleration level of 0.8 g rms distributed in the band 110–170 Hz, up to 0.75 μW of net electrical power has been harvested with our system. This work presents an important milestone in the challenge of designing a fully integrated smart conditioning interface for the capacitive e-VEHs

  1. Harvesting Triplet Excitons with Exciplex Thermally Activated Delayed Fluorescence Emitters toward High Performance Heterostructured Organic Light-Emitting Field Effect Transistors.

    Science.gov (United States)

    Song, Li; Hu, Yongsheng; Liu, Zheqin; Lv, Ying; Guo, Xiaoyang; Liu, Xingyuan

    2017-01-25

    The utilization of triplet excitons plays a key role in obtaining high emission efficiency for organic electroluminescent devices. However, to date, only phosphorescent materials have been implemented to harvest the triplet excitons in the organic light-emitting field effect transistors (OLEFETs). In this work, we report the first incorporation of exciplex thermally activated delayed fluorescence (TADF) emitters in heterostructured OLEFETs to harvest the triplet excitons. By developing a new kind of exciplex TADF emitter constituted by m-MTDATA (4,4',4″-tris(N-3-methylphenyl-N-phenylamino)triphenylamine) as the donor and OXD-7 (1,3-bis[2-(4-tert-butylphenyl)-1,3,4-oxadiazo-5-yl]benzene) as the acceptor, an exciton utilization efficiency of 74.3% for the devices was achieved. It is found that the injection barrier between hole transport layer and emission layer as well as the ratio between donor and acceptor would influence the external quantum efficiency (EQE) significantly. Devices with a maximum EQE of 3.76% which is far exceeding the reported results for devices with conventional fluorescent emitters were successfully demonstrated. Moreover, the EQE at high brightness even outperformed the result for organic light-emitting diode based on the same emitter. Our results demonstrate that the exciplex TADF emitters can be promising candidates to develop OLEFETs with high performance.

  2. Highly porous hydroxyapatite with and without local harvested bone in sinus floor augmentation: a histometric study in pigs.

    Science.gov (United States)

    Möller, Björn; Acil, Yahya; Birkenfeld, Falk; Behrens, Eleonore; Terheyden, Hendrik; Wiltfang, Jörg

    2014-07-01

    Sinus floor augmentation with autologous bone is an accepted treatment option in dental implantology. In this study, an entirely synthetic, nano-structured, hydroxyapatite-based bone substitute material (SBSM, NanoBone(®); Artoss, Rostock, Germany) was supplemented with a mixture of locally harvested bone to enhance osteogenesis. Bilateral sinus augmentation procedures were performed in eight domestic pigs using the lateral window technique. On the right side (control), 2.6 ml of SBSM was used, and on the left side (test), 2.6 ml of SBSM with additional 15% (390 μl) autologous bone was used. At the time of augmentation, a titanium implant (ITI(®)) was inserted from a laterocaudal direction. After 3 months, the sites of augmentation were removed and examined in non-decalcified sections by microradiography and fluorescence microscopy of sequentially labelled specimens and histometry. On both sides, a significant amount of newly formed bone was observed. However, a statistically significant difference in the bone-implant contact was observed in the control group (median, 28.9%) compared with the test side with the additional autologous bone (median, 40.6%) (P = 0.01). Different bone density was achieved from the coronal to apical surfaces (medians, 54.6%, 9.6%, and 27.5%) compared with the test side (medians, 55.2%, 40.6%, and 44.2%). The median of augmentation height was 8.6 mm on the control side and 11.5 mm on the test side (P = 0.01). Bone apposition was observed in both groups after 15 days. The SBSM shows acceptable results in sinus floor augmentation. The additional use of locally harvested autologous bone enhances bone density and osseointegration of the implants. © 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

  3. Porn star/stripper/escort: economic and sexual dynamics in a sex work career.

    Science.gov (United States)

    Escoffier, Jeffrey

    2007-01-01

    This article explores the career dynamics of performers in the gay male pornography industry, by focusing on a common career path- from porn star to stripper to escort. Between 1995 and 2005, most men performing in gay porn films, unlike contract actresses in the straight porn industry, have been unable to earn enough income to work exclusively as performers in front of the camera. The industry's constant search for new faces and fresh performers creates what sociologist Paul Cressey has called "the retrogressive dynamic": The longer a person works in a sexual occupation, the less one is paid, and the lower the status of the work venue. In the porn industry, one aspect of this process is referred to as "overexposure," during which the performer experiences a diminishing "fantasy potential" as fans lose erotic interest in the porn star who has appeared too frequently in too many movies. Performers attempt to confront the retrogressive dynamic by limiting the number of adult films in which they appear in a year, diversifying their sexual repertoire, or shifting into other roles within the industry (behind the camera, marketing, production, etc.). One common option is to pursue work in economically complementary forms of sex work such as stripping and escorting.

  4. Amine Solvent Regeneration for CO2 Capture Using Geothermal Energy with Advanced Stripper Configurations

    International Nuclear Information System (INIS)

    Van Wagener, D.H.; Rochelle, G.T.; Gupta, A.; Bryant, S.L.

    2014-01-01

    Absorption/stripping using alkanol-amine solvents for removing CO 2 from the flue gas of coal-fired power plants requires a substantial amount of energy. Typical designs anticipate the use of steam extraction between the Intermediate Pressure (IP) and Low Pressure (LP) turbines to provide heat for the re-boiler. Geothermal energy in the form of hot brine offers an alternative to this large parasitic load on the power generation cycle. We investigate the requirements (number and spacing of extraction/injection well pairs) to provide heat at 150 deg. C for a pilot scale (60 MWe) and a full scale (900 MWe) capture process for thirty years. The calculations are based on properties of a geopressured/geothermal aquifer near the Texas Gulf Coast. In the vicinity of a large coal-fired power plant in South Texas, this aquifer lies between 3 050 and 3 350 m (10 000 and 11 000 ft) below the surface. We present a novel design of the stripper/regenerator process based on heat exchange with the brine, discharging the brine at 100 deg. C. The results indicate that the overall process is feasible and that costs are of similar magnitude to standard designs. (authors)

  5. Post-harvest physiology

    Science.gov (United States)

    Weather and management constraints, as well as the intended use of the harvested forage, all influence the forage harvest system selected by the producer. Generally, maximum retention of dry matter from harvested forage crops is achieved at moistures intermediate between the standing fresh crop and ...

  6. Stress-anneal-induced magnetic anisotropy in highly textured Fe-Ga and Fe-Al magnetostrictive strips for bending-mode vibrational energy harvesters

    Directory of Open Access Journals (Sweden)

    Jung Jin Park

    2016-05-01

    Full Text Available Magnetostrictive Fe-Ga and Fe-Al alloys are promising materials for use in bending-mode vibrational energy harvesters. For this study, 50.8 mm × 5.0 mm × 0.5 mm strips of Fe-Ga and Fe-Al were cut from 0.50-mm thick rolled sheet. An atmospheric anneal was used to develop a Goss texture through an abnormal grain growth process. The anneal lead to large (011 grains that covered over 90% of sample surface area. The resulting highly-textured Fe-Ga and Fe-Al strips exhibited saturation magnetostriction values (λsat =  λ∥ − λ⊥ of ∼280 ppm and ∼130 ppm, respectively. To maximize 90° rotation of magnetic moments during bending of the strips, we employed compressive stress annealing (SA. Samples were heated to 500°C, and a 100-150 MPa compressive stress was applied while at 500°C for 30 minutes and while being cooled. The effectiveness of the SA on magnetic moment rotation was inferred by comparing post-SA magnetostriction with the maximum possible yield of rotated magnetic moments, which is achieved when λ∥ = λsat and λ⊥ = 0. The uniformity of the SA along the sample length and the impact of the SA on sensing/energy harvesting performance were then assessed by comparing pre- and post-SA bending-stress-induced changes in magnetization at five different locations along the samples. The SA process with a 150 MPa compressive load improved Fe-Ga actuation along the sample length from 170 to 225 ppm (from ∼60% to within ∼80% of λsat. The corresponding sensing/energy harvesting performance improved by as much as a factor of eight in the best sample, however the improvement was not at all uniform along the sample length. The SA process with a 100 MPa compressive load improved Fe-Al actuation along the sample length from 60 to 73 ppm (from ∼46% to ∼56% of λsat, indicating only a marginally effective SA and suggesting the need for modification of the SA protocol. In spite of this, the SA was effective at improving the sensing

  7. Stress-anneal-induced magnetic anisotropy in highly textured Fe-Ga and Fe-Al magnetostrictive strips for bending-mode vibrational energy harvesters

    Science.gov (United States)

    Park, Jung Jin; Na, Suok-Min; Raghunath, Ganesh; Flatau, Alison B.

    2016-05-01

    Magnetostrictive Fe-Ga and Fe-Al alloys are promising materials for use in bending-mode vibrational energy harvesters. For this study, 50.8 mm × 5.0 mm × 0.5 mm strips of Fe-Ga and Fe-Al were cut from 0.50-mm thick rolled sheet. An atmospheric anneal was used to develop a Goss texture through an abnormal grain growth process. The anneal lead to large (011) grains that covered over 90% of sample surface area. The resulting highly-textured Fe-Ga and Fe-Al strips exhibited saturation magnetostriction values (λsat = λ∥ - λ⊥) of ˜280 ppm and ˜130 ppm, respectively. To maximize 90° rotation of magnetic moments during bending of the strips, we employed compressive stress annealing (SA). Samples were heated to 500°C, and a 100-150 MPa compressive stress was applied while at 500°C for 30 minutes and while being cooled. The effectiveness of the SA on magnetic moment rotation was inferred by comparing post-SA magnetostriction with the maximum possible yield of rotated magnetic moments, which is achieved when λ∥ = λsat and λ⊥ = 0. The uniformity of the SA along the sample length and the impact of the SA on sensing/energy harvesting performance were then assessed by comparing pre- and post-SA bending-stress-induced changes in magnetization at five different locations along the samples. The SA process with a 150 MPa compressive load improved Fe-Ga actuation along the sample length from 170 to 225 ppm (from ˜60% to within ˜80% of λsat). The corresponding sensing/energy harvesting performance improved by as much as a factor of eight in the best sample, however the improvement was not at all uniform along the sample length. The SA process with a 100 MPa compressive load improved Fe-Al actuation along the sample length from 60 to 73 ppm (from ˜46% to ˜56% of λsat, indicating only a marginally effective SA and suggesting the need for modification of the SA protocol. In spite of this, the SA was effective at improving the sensing/energy harvesting

  8. Flexible one-structure arched triboelectric nanogenerator based on common electrode for high efficiency energy harvesting and self-powered motion sensing

    Science.gov (United States)

    Chen, Xi; He, Jian; Song, Linlin; Zhang, Zengxing; Tian, Zhumei; Wen, Tao; Zhai, Cong; Chen, Yi; Cho, Jundong; Chou, Xiujian; Xue, Chenyang

    2018-04-01

    Triboelectric nanogenerators are widely used because of low cost, simple manufacturing process and high output performance. In this work, a flexible one-structure arched triboelectric nanogenerator (FOAT), based on common electrode to combine the single-electrode mode and contact-separation, was designed using silicone rubber, epoxy resin and flexible electrode. The peak-to-peak short circuit current of 18μ A and the peak-to-peak open circuit voltage of 570V can be obtained from the FOAT with the size of 5×7 cm2 under the frequency of 3Hz and the pressure of 300N. The peak-to-peak short circuit current of FOAT is increased by 29% and 80%, and the peak-to-peak open circuit voltage is increased by 33% and 54% compared with single-electrode mode and contact-separation mode, respectively. FOAT realizes the combination of two generation modes, which improves the output performance of triboelectric nanogenerator (TENG). 62 light-emitting-diodes (LEDs) can be completely lit up and 2.2μ F capacitor can be easily charged to 1.2V in 9s. When the FOAT is placed at different parts of the human body, the human motion energy can be harvested and be the sensing signal for motion monitoring sensor. Based on the above characteristics, FOAT exhibits great potential in illumination, power supplies for wearable electronic devices and self-powered motion monitoring sensor via harvesting the energy of human motion.

  9. Microelectronic circuit design for energy harvesting systems

    CERN Document Server

    Di Paolo Emilio, Maurizio

    2017-01-01

    This book describes the design of microelectronic circuits for energy harvesting, broadband energy conversion, new methods and technologies for energy conversion. The author also discusses the design of power management circuits and the implementation of voltage regulators. Coverage includes advanced methods in low and high power electronics, as well as principles of micro-scale design based on piezoelectric, electromagnetic and thermoelectric technologies with control and conditioning circuit design. Provides a single-source reference to energy harvesting and its applications; Serves as a practical guide to microelectronics design for energy harvesting, with application to mobile power supplies; Enables readers to develop energy harvesting systems for wearable/mobile electronics.

  10. Electric fields, electron production, and electron motion at the stripper foil in the Los Alamos Proton Storage Ring

    International Nuclear Information System (INIS)

    Plum, M.

    1995-01-01

    The beam instability at the Los Alamos Proton Storage Ring (PSR) most likely involves coupled oscillations between electrons and protons. For this instability to occur, there must be a strong source of electrons. Investigation of the various sources of electrons in the PSR had begun. Copious electron production is expected in the injection section because this section contains the stripper foil. This foil is mounted near the center of the beam pipe, and both circulating and injected protons pass through it, thus allowing ample opportunity for electron production. This paper discusses various mechanisms for electron production, beam-induced electric fields, and electron motion in the vicinity of the foil

  11. EDITORIAL Solar harvest Solar harvest

    Science.gov (United States)

    Demming, Anna

    2010-12-01

    The first observations of the photoelectric effect date back to the early 19th century from work by Alexandre Edmond Becquerel, Heinrich Hertz, Wilhelm Hallwachs and J J Thomson. The theory behind the phenomena was clarified in a seminal paper by Einstein in 1905 and became an archetypical feature of the wave-particle description of light. A different manifestation of quantised electron excitation, whereby electrons are not emitted but excited into the valence band of the material, is what we call the photoconductive effect. As well as providing an extension to theories in fundamental physics, the phenomenon has spawned a field with enormous ramifications in the energy industry through the development of solar cells. Among advances in photovoltaic technology has been the development of organic photovoltaic technology. These devices have many benefits over their inorganic counterparts, such as light-weight, flexible material properties, as well as versatile materials' synthesis and low-cost large-scale production—all highly advantageous for manufacturing. The first organic photovoltaic systems were reported over 50 years ago [1], but the potential of the field has escalated in recent years in terms of efficiency, largely through band offsetting. Since then, great progress has been made in studies for optimising the efficiency of organic solar cells, such as the work by researchers in Germany and the Netherlands, where investigations were made into the percentage composition and annealing effects on composites of poly(3-hexylthiophene) (P3HT) and the fullerene derivative [6,6]-phenyl-C61 butyric acid methyl ester (PCBM) [2]. Hybrid devices that aim to exploit the advantages of both inorganic and organic constituents have also proven promising. One example of this is the work reported by researchers in Tunisia and France on a systematic study for optimising the composition morphology of TiO2 nanoparticles in poly(N-vinylcarbazole) (PVK), which also led to insights

  12. Status report No. 8: State uses of Exxon and Stripper Well oil overcharge funds

    International Nuclear Information System (INIS)

    Gonzales, H.; Claytor, C.P.

    1991-07-01

    From March of 1986 through early January, 1991 (when the report surveying began) state governments received $3.423 billion in funds obtained by the federal government through two major cases, based on price overcharges committed by numerous oil companies during the period of price controls, between 1973 and 1981. Furthermore, about another $1 billion may still be collected from oil companies, with roughly 1/2 to be distributed to the states (and the other 1/2 to the federal government), over the next 5 to 10 years. The role of state governments is to allocate the funds, within the specific case guidelines, to new or existing energy programs, in a way which is designed to benefit (or provide restitution to) the class or classes of purchasers who bore the burden of the overcharges. This report incorporates information collected by NCLC through telephone surveys conducted from January through March 1991. The information we collected on the status and state uses of both Exxon and Stripper Well funds is contained in the state-by-state narrative summary selection and in a series of tables at the end of the report. Each of the quarterly reports tracks final state decisions allocating use of these funds. The terms ''allocated'' and ''designated'' are used interchangeably throughout the document to mean that final state decisions have been made regarding these funds. Tracking state allocations about these funds is the only practical way for us to provide an overview of the actual status of state processes or decisions which have occurred with regard to this money. 9 tabs

  13. Felling and skidding productivity and harvesting cost in southern pine forests

    Science.gov (United States)

    R.A. Kluender; B.J. Stokes

    1996-01-01

    Sixteen stands were harvested at various levels of basal area removed (intensity). Chainsaw felling productivity was more sensitive to stem diameter than harvest intensity. Skidding productivity was highest when removing large trees at high intensity. Harvesting cost was more sensitive to stem size than harvest intensity, although harvest intensity was a very important...

  14. Harvesting of microalgae by bio-flocculation

    NARCIS (Netherlands)

    Salim, S.; Bosma, R.; Vermuë, M.H.; Wijffels, R.H.

    2011-01-01

    The high-energy input for harvesting biomass makes current commercial microalgal biodiesel production economically unfeasible. A novel harvesting method is presented as a cost and energy efficient alternative: the bio-flocculation by using one flocculating microalga to concentrate the

  15. Applying new technologies to transform blueberry harvesting

    Science.gov (United States)

    The growth of the blueberry industry in the past three decades has been remarkable. However, labor shortage for hand harvesting, increasingly high labor costs, and low harvest efficiencies are becoming bottlenecks for sustainable development of the fresh market blueberry production. In this study ...

  16. Fog Harvesting with Harps.

    Science.gov (United States)

    Shi, Weiwei; Anderson, Mark J; Tulkoff, Joshua B; Kennedy, Brook S; Boreyko, Jonathan B

    2018-04-11

    Fog harvesting is a useful technique for obtaining fresh water in arid climates. The wire meshes currently utilized for fog harvesting suffer from dual constraints: coarse meshes cannot efficiently capture microscopic fog droplets, whereas fine meshes suffer from clogging issues. Here, we design and fabricate fog harvesters comprising an array of vertical wires, which we call "fog harps". Under controlled laboratory conditions, the fog-harvesting rates for fog harps with three different wire diameters were compared to conventional meshes of equivalent dimensions. As expected for the mesh structures, the mid-sized wires exhibited the largest fog collection rate, with a drop-off in performance for the fine or coarse meshes. In contrast, the fog-harvesting rate continually increased with decreasing wire diameter for the fog harps due to efficient droplet shedding that prevented clogging. This resulted in a 3-fold enhancement in the fog-harvesting rate for the harp design compared to an equivalent mesh.

  17. Safety evaluation of the ITP filter/stripper test runs and quiet time runs using simulant solution

    International Nuclear Information System (INIS)

    Gupta, M.K.

    1993-10-01

    In-Tank Precipitation is a process for removing radioactivity from the salt stored in the Waste Management Tank Farm at Savannah River. The process involves precipitation of cesium and potassium with sodium tetraphenylborate (STPB) and adsorption of strontium and actinides on insoluble sodium titanate (ST) particles. The purpose of this report is to provide the technical bases for the evaluation of Unreviewed Safety Question for the In-Tank Precipitation (ITP) Filter/Stripper Test Runs and Quiet Time Runs Program. The primary objective of the filter-stripper test runs and quiet time runs program is to ensure that the facility will fulfill its design basis function prior to the introduction of radioactive feed. Risks associated with the program are identified and include hazards, both personnel and environmental, associated with handling the chemical simulants; the presence of flammable materials; the potential for damage to the permanenet ITP and Tank Farm facilities. The risks, potential accident scenarios, and safeguards either in place or planned are discussed at length

  18. Safety evaluation of the ITP filter/stripper test runs and quiet time runs using simulant solution

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, M.K.

    1993-10-01

    In-Tank Precipitation is a process for removing radioactivity from the salt stored in the Waste Management Tank Farm at Savannah River. The process involves precipitation of cesium and potassium with sodium tetraphenylborate (STPB) and adsorption of strontium and actinides on insoluble sodium titanate (ST) particles. The purpose of this report is to provide the technical bases for the evaluation of Unreviewed Safety Question for the In-Tank Precipitation (ITP) Filter/Stripper Test Runs and Quiet Time Runs Program. The primary objective of the filter-stripper test runs and quiet time runs program is to ensure that the facility will fulfill its design basis function prior to the introduction of radioactive feed. Risks associated with the program are identified and include hazards, both personnel and environmental, associated with handling the chemical simulants; the presence of flammable materials; the potential for damage to the permanenet ITP and Tank Farm facilities. The risks, potential accident scenarios, and safeguards either in place or planned are discussed at length.

  19. Emittance measurements at the new UNILAC-pre-stripper using a pepper-pot with a PC-controlled CCD-camera

    CERN Document Server

    Dolinska, M E; Forck, P; Hoffmann, T; Liakin, D; Peters, A; Strehl, P

    2000-01-01

    The complex mathematical algorithms and procedures to extract emittance data from intensity distributions measured with a single shot pepper-pot device are described. First results of mathematical evaluation from the commissioning of the new GSI pre-stripper linac structures are presented.

  20. Measurements of oleic acid among individual kernels harvested from test plots of purified runner and spanish high oleic seed

    Science.gov (United States)

    Normal oleic peanuts are often found within commercial lots of high oleic peanuts when sampling among individual kernels. Kernels not meeting high oleic threshold could be true contamination with normal oleic peanuts introduced via poor handling, or kernels not meeting threshold could be immature a...

  1. 1970 Oregon timber harvest.

    Science.gov (United States)

    Brian R. Wall

    1971-01-01

    The 1970 Oregon timber harvest of 7.98 billion board feet was the lowest recorded since the recession year of 1961 when 7.41 billion board feet of timber was produced. The 1970 log production figure was 12.8 percent below the 1969 harvest, the second consecutive year of declining production in Oregon.

  2. Effect of harvest date and stalk section on selected strength ...

    African Journals Online (AJOL)

    Background: The time required to harvest plant crops is important to the plant properties. It is affected by design of the harvest equipment and the desire for high-quality products with low energy usage. Materials and Methods: Strength characteristics of Origanum onites L., an important medicinal aromatic plant, harvested on ...

  3. Maple Sugar Harvesting/Wild Rice Harvesting.

    Science.gov (United States)

    Minneapolis Public Schools, MN.

    Comprised of two separate booklets, this resource unit assists elementary teachers in explaining how the Ojibwe people harvest maple sugar and wild rice. The first booklet explains the procedure of tapping the maple trees for sap, preparation for boiling the sap, and the three forms the sugar is made into (granulated, "molded," and…

  4. Electromagnetic energy harvester for harvesting acoustic energy

    Indian Academy of Sciences (India)

    Farid U Khan

    Acoustics; energy harvesting; electromagnetic; Helmholtz resonator; sound pressure level; suspended coil. ... WSNs, which are supposed to operate for longer period of time. However ... several ambient energies such as wind, thermal, vibration, and solar are ..... textile plants in Northern India with specific reference to noise.

  5. Energy Harvesting From Low Frequency Applications Using Piezoelectric Materials

    Energy Technology Data Exchange (ETDEWEB)

    Li, Huidong; Tian, Chuan; Deng, Zhiqun

    2014-11-06

    This paper reviewed the state of research on piezoelectric energy harvesters. Various types of harvester configurations, piezoelectric materials, and techniques used to improve the mechanical-to-electrical energy conversion efficiency were discussed. Most of the piezoelectric energy harvesters studied today have focused on scavenging mechanical energy from vibration sources due to their abundance in both natural and industrial environments. Cantilever beams have been the most studied structure for piezoelectric energy harvester to date because of the high responsiveness to small vibrations.

  6. Organic Diode Rectifiers Based on a High-Performance Conjugated Polymer for a Near-Field Energy-Harvesting Circuit.

    Science.gov (United States)

    Higgins, Stuart G; Agostinelli, Tiziano; Markham, Steve; Whiteman, Robert; Sirringhaus, Henning

    2017-12-01

    Organic diodes manufactured on a plastic substrate capable of rectifying a high-frequency radio-frequency identification signal (13.56 MHz), with sufficient power to operate an interactive smart tag, are reported. A high-performance conjugated semiconductor (an indacenodithiophene-benzothiadiazole copolymer) is combined with a carefully optimized architecture to satisfy the electrical requirements for an organic-semiconductor-based logic chip. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Triboelectric effect in energy harvesting

    Science.gov (United States)

    Logothetis, I.; Vassiliadis, S.; Siores, E.

    2017-10-01

    With the development of wearable technology, much research has been undertaken in the field of flexible and stretchable electronics for use in interactive attire. The challenging problem wearable technology faces is the ability to provide energy whilst keeping the endproduct comfortable, light, ergonomic and nonintrusive. Energy harvesting, or energy scavenging as it is also known, is the process by which ambient energy is captured and converted into electric energy. The triboelectric effect converts mechanical energy into electrical energy based on the coupling effect of triboelectrification and electrostatic induction and is utilized as the basis for triboelectric generators (TEG). TEG’s are promising for energy harvesting due their high output power and efficiency in conjunction with simple and economical production. Due to the wide availability of materials and ease of integration, in order to produce the triboelectric effect such functional materials are effective for wearable energy harvesting systems. Flexible TEG’s can be built and embedded into attire, although a thorough understanding of the underlying principle of how TEG’s operate needs to be comprehended for the development and in incorporation in smart technical textiles. This paper presents results associated with TEG’S and discusses their suitability for energy harvesting in textiles structures.

  8. High-temperature controlled atmosphere for post-harvest control of Indian meal moth (Lepidoptera: Pyralidae) on preserved flowers.

    Science.gov (United States)

    Sauer, Jodi A; Shelton, Mark D

    2002-10-01

    High carbon dioxide atmospheres combined with high temperature were effective for controlling Indian meal moth, Plodia interpunctella (Hübner) pupae. Pupae were exposed to atmospheres of 60, 80, or 98% carbon dioxide (CO2) in nitrogen (N2), or 60 or 80% CO2 in air at temperatures of 26.7 degrees C or 32.2 degrees C and 60% RH. Controlled atmosphere treatments at 32.2 degrees C controlled pupae faster than the same treatments at the lower temperature. At both temperatures high CO2 concentration treatments combined with nitrogen killed pupae faster than high CO2 concentration treatments combined with air. Exposure to 80% carbon dioxide mixed with nitrogen was the most effective treatment causing 100% mortality in 12 h at 32.2 degrees C and 93.3% mortality in 18 h at 26.6 degrees C. High-temperature controlled atmosphere treatments had no adverse effects on quality of two preserved floral products, Limonium sinuatum (L.) and Gypsophila elegans (Bieb.), tested for 12, 18, and 24 h according to industry standards.

  9. Bundling harvester; Nippukorjausharvesteri

    Energy Technology Data Exchange (ETDEWEB)

    Koponen, K. [Eko-Log Oy, Kuopio (Finland)

    1996-12-31

    The staring point of the project was to design and construct, by taking the silvicultural point of view into account, a harvesting and processing system especially for energy-wood, containing manually driven bundling harvester, automatizing of the harvester, and automatized loading. The equipment forms an ideal method for entrepreneur`s-line harvesting. The target is to apply the system also for owner`s-line harvesting. The profitability of the system promotes the utilization of the system in both cases. The objectives of the project were: to construct a test equipment and prototypes for all the project stages, to carry out terrain and strain tests in order to examine the usability and durability, as well as the capacity of the machine, to test the applicability of the Eko-Log system in simultaneous harvesting of energy and pulp woods, and to start the marketing and manufacturing of the products. The basic problems of the construction of the bundling harvester have been solved using terrain-tests. The prototype machine has been shown to be operable. Loading of the bundles to form sufficiently economically transportable loads has been studied, and simultaneously, the branch-biomass has been tried to be utilized without loosing the profitability of transportation. The results have been promising, and will promote the profitable utilization of wood-energy

  10. Bundling harvester; Nippukorjausharvesteri

    Energy Technology Data Exchange (ETDEWEB)

    Koponen, K [Eko-Log Oy, Kuopio (Finland)

    1997-12-31

    The staring point of the project was to design and construct, by taking the silvicultural point of view into account, a harvesting and processing system especially for energy-wood, containing manually driven bundling harvester, automatizing of the harvester, and automatized loading. The equipment forms an ideal method for entrepreneur`s-line harvesting. The target is to apply the system also for owner`s-line harvesting. The profitability of the system promotes the utilization of the system in both cases. The objectives of the project were: to construct a test equipment and prototypes for all the project stages, to carry out terrain and strain tests in order to examine the usability and durability, as well as the capacity of the machine, to test the applicability of the Eko-Log system in simultaneous harvesting of energy and pulp woods, and to start the marketing and manufacturing of the products. The basic problems of the construction of the bundling harvester have been solved using terrain-tests. The prototype machine has been shown to be operable. Loading of the bundles to form sufficiently economically transportable loads has been studied, and simultaneously, the branch-biomass has been tried to be utilized without loosing the profitability of transportation. The results have been promising, and will promote the profitable utilization of wood-energy

  11. High yielding tropical energy crops for bioenergy production: Effects of plant components, harvest years and locations on biomass composition.

    Science.gov (United States)

    Surendra, K C; Ogoshi, Richard; Zaleski, Halina M; Hashimoto, Andrew G; Khanal, Samir Kumar

    2018-03-01

    The composition of lignocellulosic feedstock, which depends on crop type, crop management, locations and plant parts, significantly affects the conversion efficiency of biomass into biofuels and biobased products. Thus, this study examined the composition of different parts of two high yielding tropical energy crops, Energycane and Napier grass, collected across three locations and years. Significantly higher fiber content was found in the leaves of Energycane than stems, while fiber content was significantly higher in the stems than the leaves of Napier grass. Similarly, fiber content was higher in Napier grass than Energycane. Due to significant differences in biomass composition between the plant parts within a crop type, neither biological conversion, including anaerobic digestion, nor thermochemical pretreatment alone is likely to efficiently convert biomass components into biofuels and biobased products. However, combination of anaerobic digestion with thermochemical conversion technologies could efficiently utilize biomass components in generating biofuels and biobased products. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. A facile strategy for the fabrication of a bioinspired hydrophilic-superhydrophobic patterned surface for highly efficient fog-harvesting

    KAUST Repository

    Wang, Yuchao

    2015-08-10

    Fog water collection represents a meaningful effort in the places where regular water sources, including surface water and ground water, are scarce. Inspired by the amazing fog water collection capability of Stenocara beetles in the Namib Desert and based on the recent work in biomimetic water collection, this work reported a facile, easy-to-operate, and low-cost method for the fabrication of hydrophilic-superhydrophobic patterned hybrid surface toward highly efficient fog water collection. The essence of the method is incorporating a (super)hydrophobically modified metal-based gauze onto the surface of a hydrophilic polystyrene (PS) flat sheet by a simple lab oven-based thermal pressing procedure. The produced hybrid patterned surfaces consisted of PS patches sitting within the holes of the metal gauzes. The method allows for an easy control over the pattern dimension (e.g., patch size) by varying gauze mesh size and thermal pressing temperature, which is then translated to an easy optimization of the ultimate fog water collection efficiency. Given the low-cost and wide availability of both PS and metal gauze, this method has a great potential for scaling-up. The results showed that the hydrophilic-superhydrophobic patterned hybrid surfaces with a similar pattern size to Stenocara beetles’s back pattern produced significantly higher fog collection efficiency than the uniformly (super)hydrophilic or (super)hydrophobic surfaces. This work contributes to general effort in fabricating wettability patterned surfaces and to atmospheric water collection for direct portal use.

  13. Highly efficient capture and harvest of circulating tumor cells on a microfluidic chip integrated with herringbone and micropost arrays.

    Science.gov (United States)

    Xue, Peng; Wu, Yafeng; Guo, Jinhong; Kang, Yuejun

    2015-04-01

    Circulating tumor cells (CTCs), which are derived from primary tumor site and transported to distant organs, are considered as the major cause of metastasis. So far, various techniques have been applied for CTC isolation and enumeration. However, there exists great demand to improve the sensitivity of CTC capture, and it remains challenging to elute the cells efficiently from device for further biomolecular and cellular analyses. In this study, we fabricate a dual functional chip integrated with herringbone structure and micropost array to achieve CTC capture and elution through EpCAM-based immunoreaction. Hep3B tumor cell line is selected as the model of CTCs for processing using this device. The results demonstrate that the capture limit of Hep3B cells can reach up to 10 cells (per mL of sample volume) with capture efficiency of 80% on average. Moreover, the elution rate of the captured Hep3B cells can reach up to 69.4% on average for cell number ranging from 1 to 100. These results demonstrate that this device exhibits dual functions with considerably high capture rate and elution rate, indicating its promising capability for cancer diagnosis and therapeutics.

  14. High efficiency light harvesting by carotenoids in the LH2 complex from photosynthetic bacteria: unique adaptation to growth under low-light conditions.

    Science.gov (United States)

    Magdaong, Nikki M; LaFountain, Amy M; Greco, Jordan A; Gardiner, Alastair T; Carey, Anne-Marie; Cogdell, Richard J; Gibson, George N; Birge, Robert R; Frank, Harry A

    2014-09-25

    Rhodopin, rhodopinal, and their glucoside derivatives are carotenoids that accumulate in different amounts in the photosynthetic bacterium, Rhodoblastus (Rbl.) acidophilus strain 7050, depending on the intensity of the light under which the organism is grown. The different growth conditions also have a profound effect on the spectra of the bacteriochlorophyll (BChl) pigments that assemble in the major LH2 light-harvesting pigment-protein complex. Under high-light conditions the well-characterized B800-850 LH2 complex is formed and accumulates rhodopin and rhodopin glucoside as the primary carotenoids. Under low-light conditions, a variant LH2, denoted B800-820, is formed, and rhodopinal and rhodopinal glucoside are the most abundant carotenoids. The present investigation compares and contrasts the spectral properties and dynamics of the excited states of rhodopin and rhodopinal in solution. In addition, the systematic differences in pigment composition and structure of the chromophores in the LH2 complexes provide an opportunity to explore the effect of these factors on the rate and efficiency of carotenoid-to-BChl energy transfer. It is found that the enzymatic conversion of rhodopin to rhodopinal by Rbl. acidophilus 7050 grown under low-light conditions results in nearly 100% carotenoid-to-BChl energy transfer efficiency in the LH2 complex. This comparative analysis provides insight into how photosynthetic systems are able to adapt and survive under challenging environmental conditions.

  15. Energy harvesting for microsystems

    DEFF Research Database (Denmark)

    Xu, Ruichao

    The purpose of this project is to design and fabricate piezoelectric energy harvesters based on integration of Pb(ZrxTi1-x)O3 (PZT) thick film technology and silicon microtechnology. The fabrication processes are carried out in close collaboration with Meggitt Sensing Systems (MSS) who has...... the unique expertise to screen print piezoelectric thick film layers, thus all screen printing steps are done by MSS while the silicon micromachining is carried out at Danchip facility at DTU. The presented energy harvesters are all based on using piezoelectric thick film operating in the 31-mode to generate...... power when strained. Three archetypes of the numerous fabricated energy harvesters will be presented in detail, they represent three major milestones in this project. The first energy harvester archetype has an unimorph cantilever beam, which consists of a 20 µm silicon layer and 10-30 µm screen printed...

  16. African Urban Harvest

    International Development Research Centre (IDRC) Digital Library (Canada)

    Urban Harvest, a system-wide initiative of the Consultative Group on Agricultural ...... and urban old, using criteria of population density, land availability, and the prevalence of crop ...... Contact between milk and containers or the environment;.

  17. Energy harvesting water vehicle

    KAUST Repository

    Singh, Devendra

    2018-01-01

    An efficient energy harvesting (EEH) water vehicle is disclosed. The base of the EEH water vehicle is fabricated with rolling cylindrical drums that can rotate freely in the same direction of the water medium. The drums reduce the drag

  18. RF power harvesting: a review on designing methodologies and applications

    Science.gov (United States)

    Tran, Le-Giang; Cha, Hyouk-Kyu; Park, Woo-Tae

    2017-12-01

    Wireless power transmission was conceptualized nearly a century ago. Certain achievements made to date have made power harvesting a reality, capable of providing alternative sources of energy. This review provides a summ ary of radio frequency (RF) power harvesting technologies in order to serve as a guide for the design of RF energy harvesting units. Since energy harvesting circuits are designed to operate with relatively small voltages and currents, they rely on state-of-the-art electrical technology for obtaining high efficiency. Thus, comprehensive analysis and discussions of various designs and their tradeoffs are included. Finally, recent applications of RF power harvesting are outlined.

  19. ECRIS sources for highly charged ions

    International Nuclear Information System (INIS)

    Geller, R.

    1991-01-01

    The so-called Philips ionization gauge ion sources (PIGIS) were used until quite recently in heavy ion accelerators so multiply charged ions could only be obtained by incorporating a stripper to remove electrons. Electron cyclotron resonance ion sources (ECRIS) now dominate as they produce more highly charged ions. (orig.)

  20. Performance Assessment of Hazardous Air Pollutant (HAP)Free Chemical Paint Strippers on Military Coatings for Validation to Federal Specification TT-R-2918A

    Science.gov (United States)

    2016-03-01

    ARL-TN-0742 ● MAR 2016 US Army Research Laboratory Performance Assessment of Hazardous Air Pollutant (HAP)–Free Chemical Paint...the originator. ARL-TN-0742 ● MAR 2016 US Army Research Laboratory Performance Assessment of Hazardous Air Pollutant (HAP...COVERED (From - To) 1–30 April 2014 4. TITLE AND SUBTITLE Performance Assessment of Hazardous Air Pollutant (HAP)–Free Chemical Paint Strippers

  1. Water harvest via dewing.

    Science.gov (United States)

    Lee, Anna; Moon, Myoung-Woon; Lim, Hyuneui; Kim, Wan-Doo; Kim, Ho-Young

    2012-07-10

    Harvesting water from humid air via dewing can provide a viable solution to a water shortage problem where liquid-phase water is not available. Here we experimentally quantify the effects of wettability and geometry of the condensation substrate on the water harvest efficiency. Uniformly hydrophilic surfaces are found to exhibit higher rates of water condensation and collection than surfaces with lower wettability. This is in contrast to a fog basking method where the most efficient surface consists of hydrophilic islands surrounded by hydrophobic background. A thin drainage path in the lower portion of the condensation substrate is revealed to greatly enhance the water collection efficiency. The optimal surface conditions found in this work can be used to design a practical device that harvests water as its biological counterpart, a green tree frog, Litoria caerulea , does during the dry season in tropical northern Australia.

  2. Hybrid energy harvesting using active thermal backplane

    Science.gov (United States)

    Kim, Hyun-Wook; Lee, Dong-Gun

    2016-04-01

    In this study, we demonstrate the concept of a new hybrid energy harvesting system by combing solar cells with magneto-thermoelectric generator (MTG, i.e., thermal energy harvesting). The silicon solar cell can easily reach high temperature under normal operating conditions. Thus the heated solar cell becomes rapidly less efficient as the temperature of solar cell rises. To increase the efficiency of the solar cell, air or water-based cooling system is used. To surpass conventional cooling devices requiring additional power as well as large working space for air/water collectors, we develop a new technology of pairing an active thermal backplane (ATB) to solar cell. The ATB design is based on MTG technology utilizing the physics of the 2nd order phase transition of active ferromagnetic materials. The MTG is cost-effective conversion of thermal energy to electrical energy and is fundamentally different from Seebeck TEG devices. The ATB (MTG) is in addition to being an energy conversion system, a very good conveyor of heat through both conduction and convection. Therefore, the ATB can provide dual-mode for the proposed hybrid energy harvesting. One is active convective and conductive cooling for heated solar cell. Another is active thermal energy harvesting from heat of solar cell. These novel hybrid energy harvesting device have potentially simultaneous energy conversion capability of solar and thermal energy into electricity. The results presented can be used for better understanding of hybrid energy harvesting system that can be integrated into commercial applications.

  3. Harvesting soil with potatoes

    DEFF Research Database (Denmark)

    Egelyng, Henrik

    2017-01-01

    Norwegian authorities demand soil leaving potato packing plants to be deposited as waste. Depositing soil from potato processing plants is associated with significant cost for Norwegian producers. Therefore CYCLE investigated potato soil harvesting from an innovation and socio-economic perspective....

  4. Designing A General Deep Web Harvester by Harvestability Factor

    NARCIS (Netherlands)

    Khelghati, Mohammadreza; van Keulen, Maurice; Hiemstra, Djoerd

    2014-01-01

    To make deep web data accessible, harvesters have a crucial role. Targeting different domains and websites enhances the need of a general-purpose harvester which can be applied to different settings and situations. To develop such a harvester, a large number of issues should be addressed. To have

  5. Magnetic Nanocomposite Cilia Energy Harvester

    KAUST Repository

    Khan, Mohammed Asadullah; Alfadhel, Ahmed; Kosel, Jü rgen

    2016-01-01

    An energy harvester capable of converting low frequency vibrations into electrical energy is presented. The operating principle, fabrication process and output characteristics at different frequencies are discussed. The harvester is realized

  6. Determination of Optimal Harvest Time of Chuchung Variety Green Rice(®) (Oryza sativa L.) with High Contents of GABA, γ-Oryzanol, and α-Tocopherol.

    Science.gov (United States)

    Kim, Hoon; Kim, Oui-Woung; Ha, Ae Wha; Park, Soojin

    2016-06-01

    In our previous study, an early-maturing variety of rice (Oryza sativa L.), Jinbu can have feature with unique green color, various phytochemicals as well as nutritive components by the optimal early harvesting, called Green Rice(®) (GR). The aims of the present field experiments were to evaluate the changes in the weight of 1,000 kernels, yield, and contents of proximate and bioactive compounds in Chuchung, a mid-late maturing variety, during the pre-harvest maturation of rough rice and to research the appropriate harvest time and potent bioactivity of Chuchung GR. The weights of 1,000 kernels of Chuchung GR dramatically increased until 27 days after heading (DAH). The yields of Chuchung GR declined after 27 DAH and significantly declined to 0.0% after 45 DAH. The caloric value and total mineral contents were higher in the GR than in the full ripe stage, the brown rice (BR). In the GR, the contents of bioactive compounds, such as γ-aminobutyric acid, γ-oryzanol, and α-tocopherol, were much higher (P<0.05) than those in the BR, specifically during 24~27 DAH. Therefore, bioactive Chuchung GR can be produced with a reasonable yield at 24~27 DAH and it could be useful for applications in various nutritive and functional food products.

  7. Determination of Optimal Harvest Time of Chuchung Variety Green Rice® (Oryza sativa L.) with High Contents of GABA, γ-Oryzanol, and α-Tocopherol

    Science.gov (United States)

    Kim, Hoon; Kim, Oui-Woung; Ha, Ae Wha; Park, Soojin

    2016-01-01

    In our previous study, an early-maturing variety of rice (Oryza sativa L.), Jinbu can have feature with unique green color, various phytochemicals as well as nutritive components by the optimal early harvesting, called Green Rice® (GR). The aims of the present field experiments were to evaluate the changes in the weight of 1,000 kernels, yield, and contents of proximate and bioactive compounds in Chuchung, a mid-late maturing variety, during the pre-harvest maturation of rough rice and to research the appropriate harvest time and potent bioactivity of Chuchung GR. The weights of 1,000 kernels of Chuchung GR dramatically increased until 27 days after heading (DAH). The yields of Chuchung GR declined after 27 DAH and significantly declined to 0.0% after 45 DAH. The caloric value and total mineral contents were higher in the GR than in the full ripe stage, the brown rice (BR). In the GR, the contents of bioactive compounds, such as γ-aminobutyric acid, γ-oryzanol, and α-tocopherol, were much higher (P<0.05) than those in the BR, specifically during 24~27 DAH. Therefore, bioactive Chuchung GR can be produced with a reasonable yield at 24~27 DAH and it could be useful for applications in various nutritive and functional food products. PMID:27390725

  8. Helical Piezoelectric Energy Harvester and Its Application to Energy Harvesting Garments

    Directory of Open Access Journals (Sweden)

    Minsung Kim

    2017-04-01

    Full Text Available In this paper, we propose a helical piezoelectric energy harvester, examine its application to clothes in the form of an energy harvesting garment, and analyze its design and characteristics. The helical harvester is composed of an elastic core and a polymer piezoelectric strap twining the core. The fabricated harvester is highly elastic and can be stretched up to 158% of its initial length. Following the experiments using three different designs, the maximum output power is measured as 1.42 mW at a 3 MΩ load resistance and 1 Hz motional frequency. The proposed helical harvesters are applied at four positions of stretchable tight-fitting sportswear, namely shoulder, arm joint, knee, and hip. The maximum output voltage is measured as more than 20 V from the harvester at the knee position during intended body motions. In addition, electric power is also generated from this energy harvesting garment during daily human motions, which is about 3.9 V at the elbow, 3.1 V at the knee, and 4.4 V at the knee during push-up, walking, and squatting motions, respectively.

  9. Piezoelectric energy harvesting

    Energy Technology Data Exchange (ETDEWEB)

    Howells, Christopher A [Power Technology Branch, US Army, CERDEC, C2D, Ft. Belvoir, VA 22060-5816 (United States)

    2009-07-15

    Piezoelectric materials can be used to convert oscillatory mechanical energy into electrical energy. This technology, together with innovative mechanical coupling designs, can form the basis for harvesting energy from mechanical motion. Piezoelectric energy can be harvested to convert walking motion from the human body into electrical power. Recently four proof-of-concept Heel Strike Units were developed where each unit is essentially a small electric generator that utilizes piezoelectric elements to convert mechanical motion into electrical power in the form factor of the heel of a boot. The results of the testing and evaluation and the performance of this small electric generator are presented. The generator's conversion of mechanical motion into electrical power, the processes it goes through to produce useable power and commercial applications of the Heel Strike electric generator are discussed. (author)

  10. Piezoelectric energy harvesting

    International Nuclear Information System (INIS)

    Howells, Christopher A

    2009-01-01

    Piezoelectric materials can be used to convert oscillatory mechanical energy into electrical energy. This technology, together with innovative mechanical coupling designs, can form the basis for harvesting energy from mechanical motion. Piezoelectric energy can be harvested to convert walking motion from the human body into electrical power. Recently four proof-of-concept Heel Strike Units were developed where each unit is essentially a small electric generator that utilizes piezoelectric elements to convert mechanical motion into electrical power in the form factor of the heel of a boot. The results of the testing and evaluation and the performance of this small electric generator are presented. The generator's conversion of mechanical motion into electrical power, the processes it goes through to produce useable power and commercial applications of the Heel Strike electric generator are discussed.

  11. Restoration of harvested peatlands

    International Nuclear Information System (INIS)

    Saarmets, Tiit

    1999-01-01

    A short analysis of the main topics of the IPS Symposium Peatland Restoration and Reclamation, Duluth, Minnesota, USA, 1998 is given. It has been single-mindedly recommended in Estonia so far that harvested peatland surfaces should be levelled and outflows shut. But following these recommendations will lead to an unfounded formation of marshy areas with a very low growth of plants. The reclamation of harvested peatlands for agricultural purposes is expensive and there is no commercial need for agricultural land in today's Estonia now. In the author's opinion the foreflows and intermediate ditches should be left open which would favour the growth of the brushwood to grow later into the forest of commercial value. (author)

  12. Piezoelectric Energy Harvesting Solutions

    Science.gov (United States)

    Caliò, Renato; Rongala, Udaya Bhaskar; Camboni, Domenico; Milazzo, Mario; Stefanini, Cesare; de Petris, Gianluca; Oddo, Calogero Maria

    2014-01-01

    This paper reviews the state of the art in piezoelectric energy harvesting. It presents the basics of piezoelectricity and discusses materials choice. The work places emphasis on material operating modes and device configurations, from resonant to non-resonant devices and also to rotational solutions. The reviewed literature is compared based on power density and bandwidth. Lastly, the question of power conversion is addressed by reviewing various circuit solutions. PMID:24618725

  13. Harvesting contaminants from liquid

    Science.gov (United States)

    Simpson, John T.; Hunter, Scott R.

    2016-05-31

    Disclosed are examples of apparatuses for evaporative purification of a contaminated liquid. In each example, there is a vessel for storing the contaminated fluid. The vessel includes a surface coated with a layer of superhydrophobic material and the surface is at least partially in contact with the contaminated liquid. The contaminants do not adhere to the surface as the purified liquid evaporates, thus allowing the contaminants to be harvested.

  14. A Galloping Energy Harvester with Attached Flow

    Science.gov (United States)

    Denissenko, Petr; Khovanov, Igor; Tucker-Harvey, Sam

    2017-11-01

    Aeroelastic energy harvesters are a promising technology for the operation of wireless sensors and microelectromechanical systems, as well as providing the possibility of harvesting wind energy in applications were conventional wind turbines are ineffective, such as in highly turbulent flows, or unreliable, such as in harsh environmental conditions. The development of aeroelastic energy harvesters to date has focused on the flutter of airfoils, the galloping of prismatic structures, and the vortex induced vibrations. We present a novel type of galloping energy harvester with the flow becoming attached when the oscillation amplitude is high enough. With the flow attached, the harvester blade acts closer to an aerofoil than a bluff body, which results in a higher efficiency. The dynamics of a prototype device has been characterised experimentally with the use of a motion tracking system. The flow structure in the vicinity of the device has been studied using smoke visualisation and PIV measurements. A lumped parameter mathematical model has been developed and related to the experimental results.

  15. Terra Harvest software architecture

    Science.gov (United States)

    Humeniuk, Dave; Klawon, Kevin

    2012-06-01

    Under the Terra Harvest Program, the DIA has the objective of developing a universal Controller for the Unattended Ground Sensor (UGS) community. The mission is to define, implement, and thoroughly document an open architecture that universally supports UGS missions, integrating disparate systems, peripherals, etc. The Controller's inherent interoperability with numerous systems enables the integration of both legacy and future UGS System (UGSS) components, while the design's open architecture supports rapid third-party development to ensure operational readiness. The successful accomplishment of these objectives by the program's Phase 3b contractors is demonstrated via integration of the companies' respective plug-'n'-play contributions that include controllers, various peripherals, such as sensors, cameras, etc., and their associated software drivers. In order to independently validate the Terra Harvest architecture, L-3 Nova Engineering, along with its partner, the University of Dayton Research Institute, is developing the Terra Harvest Open Source Environment (THOSE), a Java Virtual Machine (JVM) running on an embedded Linux Operating System. The Use Cases on which the software is developed support the full range of UGS operational scenarios such as remote sensor triggering, image capture, and data exfiltration. The Team is additionally developing an ARM microprocessor-based evaluation platform that is both energy-efficient and operationally flexible. The paper describes the overall THOSE architecture, as well as the design decisions for some of the key software components. Development process for THOSE is discussed as well.

  16. Harvesting budworm-damaged stands for fuel

    Energy Technology Data Exchange (ETDEWEB)

    Henley, S.G. (York, Sunbury, Charlotte Wood Products Marketing Board, (Canada))

    1985-01-01

    This project was initiated to demonstrate the economics and logistics of harvesting budworm-damaged stands for use as fuel. Dead spruce and balsam fir were to be harvested from small private woodlots in southwestern New Brunswick, using an integrated, full-tree harvesting system to produce wood chip fuel and other forest products. The overall objectives of the study are listed. The harvesting equipment and the selection of sites are discussed. The most efficient methods of finding candidate woodlots was found to be by advertising and word of mouth. Contact was made with 85 woodlot owners, and 45 woodlots were visited and evaluated for their suitability. A further 150 management plans were screened and rejected for various reasons. Only 2 woodlots were initially recognized as potential sites; however, after showing some interest, the owners decided not to participate. The reasons for the rejection of the various woodlots are listed. The fact that a number of owners were against clearcutting, and, in some cases, against any cutting, and that others showed no interest in the study, is attributed to the high percentage of white-collar workers owning woodlots. Other strategies for harvesting dead or scrap wood are suggested. 1 ref., 1 tab.

  17. Energy harvesting from hydraulic pressure fluctuations

    International Nuclear Information System (INIS)

    Cunefare, K A; Skow, E A; Erturk, A; Savor, J; Verma, N; Cacan, M R

    2013-01-01

    State-of-the-art hydraulic hose and piping systems employ integral sensor nodes for structural health monitoring to avoid catastrophic failures. Energy harvesting in hydraulic systems could enable self-powered wireless sensor nodes for applications such as energy-autonomous structural health monitoring and prognosis. Hydraulic systems inherently have a high energy intensity associated with the mean pressure and flow. Accompanying the mean pressure is the dynamic pressure ripple, which is caused by the action of pumps and actuators. Pressure ripple is a deterministic source with a periodic time-domain behavior conducive to energy harvesting. An energy harvester prototype was designed for generating low-power electricity from pressure ripples. The prototype employed an axially-poled off-the-shelf piezoelectric stack. A housing isolated the stack from the hydraulic fluid while maintaining a mechanical coupling allowing for dynamic-pressure-induced deflection of the stack. The prototype exhibited an off-resonance energy harvesting problem since the fundamental resonance of the piezoelectric stack was much higher than the frequency content of the pressure ripple. The prototype was designed to provide a suitable power output for powering sensors with a maximum output of 1.2 mW. This work also presents electromechanical model simulations and experimental characterization of the piezoelectric power output from the pressure ripple in terms of the force transmitted into the harvester. (paper)

  18. NUTRIENT BALANCE IN WATER HARVESTING SOILS

    Directory of Open Access Journals (Sweden)

    Díaz, F

    2005-05-01

    Full Text Available Dryland farming on Fuerteventura and Lanzarote (Canary Islands, Spain, which has an annual rainfall of less than 150 mm/year, has been based traditionally on water harvesting techniques (known locally as “gavias”. Periods of high productivity alternate with those of very low yield. The systems are sustainable in that they reduce erosive processes, contribute to soil and soil-water conservation and are largely responsible for maintaining the soil’s farming potential. In this paper we present the chemical fertility status and nutrient balance of soils in five “gavia” systems. The results are compared with those obtained in adjacent soils where this water harvesting technique is not used. The main crops are wheat, barley, maize, lentils and chick-peas. Since neither organic nor inorganic fertilisers are used, nutrients are derived mainly from sediments carried by runoff water. Nutrients are lost mainly through crop harvesting and harvest residues. The soils where water harvesting is used have lower salt and sodium in the exchange complex, are higher in carbon, nitrogen, copper and zinc and have similar phosphorous and potassium content. It is concluded that the systems improve the soil’s natural fertility and also that natural renovation of nutrients occurs thanks to the surface deposits of sediments, which mix with the arable layer. The system helps ensure adequate fertility levels, habitual in arid regions, thus allowing dryland farming to be carried out.

  19. Evaluation of mechanical harvesting in viticulture

    Directory of Open Access Journals (Sweden)

    Pavel Zemánek

    2005-01-01

    Full Text Available Harvesting by mashine was in CZ tested at bygones century (70th. Tests rekord were bad (high share of leaf, detritus of concrete column, losses of berries.Lasting fall of worker in agriculture and vehement growth floricultural surfaces – vineyard (somewhere 19.000 hectare, requires complex rationalization and mechanization of all works stages which needs needlework. Harvisting in viniculture needs perhaps 30% of all working time (200–250 o‘clock on 1 hectare. Incidence thereof begun most of bigger producers in our country with mechanical harvisting. Technical performance of this machines turn up. There are not available data about costs and their work quality.The benefit deal with classification of mechanical harvesting (juice adhering, berries lost, damage of vineyard transaction by the help of semi-trailer and self-propelled harvesters.

  20. Nonmonotonic energy harvesting efficiency in biased exciton chains

    NARCIS (Netherlands)

    Vlaming, S.M.; Malyshev, V.A.; Knoester, J.

    2007-01-01

    We theoretically study the efficiency of energy harvesting in linear exciton chains with an energy bias, where the initial excitation is taking place at the high-energy end of the chain and the energy is harvested (trapped) at the other end. The efficiency is characterized by means of the average

  1. Techno-economic evaluation of microalgae harvesting and dewatering systems

    NARCIS (Netherlands)

    Fasaei, F.; Bitter, J.H.; Slegers, P.M.; Boxtel, van A.J.B.

    2018-01-01

    Microalgal biomass is processed into products by two main process steps: 1) harvesting and dewatering; and 2) extraction, fractionation and conversion. The performance of unit operations for harvesting and dewatering is often expressed in qualitative terms, like “high energy consumption” and “low in

  2. Differential fat harvesting

    Directory of Open Access Journals (Sweden)

    Sebastian Torres Farr

    2014-12-01

    Full Text Available Aim: Volume replacement with fillers is regularly performed with the use of diverse volumetric materials to correct different structures around the face, depending on the volume enhancement required and the thickness of the soft tissue envelope. Differential fat harvesting and posterior grafting is performed to place the correct fat parcel size for each target area, expanding the potential applications of fat. Methods: Sixty patients consecutively recruited on a first come basis undergone a facial fat grafting procedure, in private practice setting between March 2012 and October 2013. Fat grafting quantity and quality was predicted for each case. Differential harvesting was performed, with 2 fat parcels size. Processing was performed through washing. Fat infiltration was carried out through small cannulas or needles depending on the treated area. Outcomes were analysed both by the physicians and the patients at 7 days, 1 month, 3 months and 6 months through a perceived satisfaction questionnaire. Parameters considered were downtime or discomfort, skin benefits, volume restoration, reabsorption rate estimated and overall improvement. Results: Full facial differential fat grafting procedure lasted an average of 1.5-2.5 h. Average downtime was 3-4 days. Follow-up was performed to a minimum of 6 months. Both patient and physician overall satisfaction rates were mostly excellent. Adverse events like lumps or irregularities were not encountered. Conclusion: Differential fat harvesting and posterior grafting is a valid alternative, to expand the repertoire of fat use, allow a more homogeneous effect, reduce the potential complications, speed up the process, improve graft survival, and to enhance overall aesthetic outcome.

  3. Nanostructured piezoelectric energy harvesters

    CERN Document Server

    Briscoe, Joe

    2014-01-01

    This book covers a range of devices that use piezoelectricity to convert mechanical deformation into electrical energy and relates their output capabilities to a range of potential applications. Starting with a description of the fundamental principles and properties of piezo- and ferroelectric materials, where applications of bulk materials are well established, the book shows how nanostructures of these materials are being developed for energy harvesting applications. The authors show how a nanostructured device can be produced, and put in context some of the approaches that are being invest

  4. Micro energy harvesting

    CERN Document Server

    Briand, Danick; Roundy, Shad

    2015-01-01

    With its inclusion of the fundamentals, systems and applications, this reference provides readers with the basics of micro energy conversion along with expert knowledge on system electronics and real-life microdevices. The authors address different aspects of energy harvesting at the micro scale with a focus on miniaturized and microfabricated devices. Along the way they provide an overview of the field by compiling knowledge on the design, materials development, device realization and aspects of system integration, covering emerging technologies, as well as applications in power management, e

  5. Harvesting Atlantic Cod under Climate Variability

    Science.gov (United States)

    Oremus, K. L.

    2016-12-01

    Previous literature links the growth of a fishery to climate variability. This study uses an age-structured bioeconomic model to compare optimal harvest in the Gulf of Maine Atlantic cod fishery under a variable climate versus a static climate. The optimal harvest path depends on the relationship between fishery growth and the interest rate, with higher interest rates dictating greater harvests now at the cost of long-term stock sustainability. Given the time horizon of a single generation of fishermen under assumptions of a static climate, the model finds that the economically optimal management strategy is to harvest the entire stock in the short term and allow the fishery to collapse. However, if the biological growth of the fishery is assumed to vary with climate conditions, such as the North Atlantic Oscillation, there will always be pulses of high growth in the stock. During some of these high-growth years, the growth of the stock and its economic yield can exceed the growth rate of the economy even under high interest rates. This implies that it is not economically optimal to exhaust the New England cod fishery if NAO is included in the biological growth function. This finding may have theoretical implications for the management of other renewable yet exhaustible resources whose growth rates are subject to climate variability.

  6. Thermoelectrics and its energy harvesting

    National Research Council Canada - National Science Library

    Rowe, David Michael

    2012-01-01

    .... It details the latest techniques for the preparation of thermoelectric materials employed in energy harvesting, together with advances in the thermoelectric characterisation of nanoscale material...

  7. MEMS-based thick film PZT vibrational energy harvester

    DEFF Research Database (Denmark)

    Lei, Anders; Xu, Ruichao; Thyssen, Anders

    2011-01-01

    We present a MEMS-based unimorph silicon/PZT thick film vibrational energy harvester with an integrated proof mass. We have developed a process that allows fabrication of high performance silicon based energy harvesters with a yield higher than 90%. The process comprises a KOH etch using a mechan......We present a MEMS-based unimorph silicon/PZT thick film vibrational energy harvester with an integrated proof mass. We have developed a process that allows fabrication of high performance silicon based energy harvesters with a yield higher than 90%. The process comprises a KOH etch using...... a mechanical front side protection of an SOI wafer with screen printed PZT thick film. The fabricated harvester device produces 14.0 μW with an optimal resistive load of 100 kΩ from 1g (g=9.81 m s-2) input acceleration at its resonant frequency of 235 Hz....

  8. Selection of common bean inbred lines with tolerance to high moisture at harvest Seleção de linhagens de feijão com tolerância a alta umidade no momento da colheita

    Directory of Open Access Journals (Sweden)

    Lidiane Kely de Lima

    2013-04-01

    Full Text Available The occurrence of precipitation / rain in harvest bean causes damage to the product and reduces the yield. The main alternative to mitigate this problem is to obtain cultivars presenting low germination of beans in the pods under conditions of high moisture. The purpose of this study was to verify if there is genetic variability among the common bean inbred lines that are in the phase of recommendation for the South of Minas Gerais, Brazil in regard to tolerance to moisture after harvest, and identify traits that may be routinely used in selection of tolerant lines to these conditions. Ninety-five lines in the phase of recommendation by the Genetic Breeding Program from UFLA were used. After harvest, a sample of plants from each plot was removed for assessments of seed germination in the pods in a moist chamber and water absorption by pod and seed. Eight days after harvest, another sample was removed to assess seed appearance using a scoring scale. The data were submitted to analysis of variance and estimates of the Pearson phenotypic correlations were obtained among traits. Lines differ in relation to tolerance to moisture at the time of harvest, with those of higher tolerance having lighter colored seeds. The main difficulty in selection of common bean lines for tolerance to high moisture at harvest is the repeatability of the environmental conditions among crop seasons. The alternative is assessing the amount of water absorbed by pods.A ocorrência de precipitação / chuva na colheita do feijão comum provoca danos ao produto e reduz o rendimento. A principal alternativa para mitigar este problema é a obtenção de cultivares com baixa germinação de grãos nas vagens em condições de alta umidade. Neste trabalho, objetivou-se vrificar se há variabilidade genética entre as linhagens do feijoeiro que estão em fase de recomendação para o Sul de Minas Gerais quanto à tolerância à umidade após a colheita e identificar caracteres que

  9. Stand, Harvest, and Equipment Interactions in Simulated Harvesting Prescriptions

    Science.gov (United States)

    Jingxin Wang; W. Dale Greene; Bryce J. Stokes

    1998-01-01

    We evaluated potential interactions of stand type, harvesting method, and equipment in an experiment using interactive simulation. We examined three felling methods (chain saw, feller-buncher, harvester) and two extraction methods (grapple skidder and forwarder) performing clearcuts, sheltenvood cuts, and single-tree selection cuts in both an uneven-aged natural stand...

  10. Protocol and Practice in the Adaptive Management of Waterfowl Harvests

    Directory of Open Access Journals (Sweden)

    Fred Johnson

    1999-06-01

    Full Text Available Waterfowl harvest management in North America, for all its success, historically has had several shortcomings, including a lack of well-defined objectives, a failure to account for uncertain management outcomes, and inefficient use of harvest regulations to understand the effects of management. To address these and other concerns, the U.S. Fish and Wildlife Service began implementation of adaptive harvest management in 1995. Harvest policies are now developed using a Markov decision process in which there is an explicit accounting for uncontrolled environmental variation, partial controllability of harvest, and structural uncertainty in waterfowl population dynamics. Current policies are passively adaptive, in the sense that any reduction in structural uncertainty is an unplanned by-product of the regulatory process. A generalization of the Markov decision process permits the calculation of optimal actively adaptive policies, but it is not yet clear how state-specific harvest actions differ between passive and active approaches. The Markov decision process also provides managers the ability to explore optimal levels of aggregation or "management scale" for regulating harvests in a system that exhibits high temporal, spatial, and organizational variability. Progress in institutionalizing adaptive harvest management has been remarkable, but some managers still perceive the process as a panacea, while failing to appreciate the challenges presented by this more explicit and methodical approach to harvest regulation. Technical hurdles include the need to develop better linkages between population processes and the dynamics of landscapes, and to model the dynamics of structural uncertainty in a more comprehensive fashion. From an institutional perspective, agreement on how to value and allocate harvests continues to be elusive, and there is some evidence that waterfowl managers have overestimated the importance of achievement-oriented factors in

  11. Energy harvesting water vehicle

    KAUST Repository

    Singh, Devendra

    2018-01-04

    An efficient energy harvesting (EEH) water vehicle is disclosed. The base of the EEH water vehicle is fabricated with rolling cylindrical drums that can rotate freely in the same direction of the water medium. The drums reduce the drag at the vehicle-water interface. This reduction in drag corresponds to an increase in speed and/or greater fuel efficiency. The mechanical energy of the rolling cylindrical drums is also transformed into electrical energy using an electricity producing device, such as a dynamo or an alternator. Thus, the efficiency of the vehicle is enhanced in two parallel modes: from the reduction in drag at the vehicle-water interface, and from capturing power from the rotational motion of the drums.

  12. Power harvesting in helicopter rotorblades

    NARCIS (Netherlands)

    de Jong, Pieter; de Boer, Andries; Loendersloot, Richard; van der Hoogt, Peter

    2010-01-01

    Current power harvesting research has focused on bending beams and determining power output under a given excitation. For the European CleanSky – Green Rotor Craft project a tool is being developed which optimizes the piezoelectric material and placement thereof for power harvesting. It focuses on

  13. Analytical model for nonlinear piezoelectric energy harvesting devices

    International Nuclear Information System (INIS)

    Neiss, S; Goldschmidtboeing, F; M Kroener; Woias, P

    2014-01-01

    In this work we propose analytical expressions for the jump-up and jump-down point of a nonlinear piezoelectric energy harvester. In addition, analytical expressions for the maximum power output at optimal resistive load and the 3 dB-bandwidth are derived. So far, only numerical models have been used to describe the physics of a piezoelectric energy harvester. However, this approach is not suitable to quickly evaluate different geometrical designs or piezoelectric materials in the harvester design process. In addition, the analytical expressions could be used to predict the jump-frequencies of a harvester during operation. In combination with a tuning mechanism, this would allow the design of an efficient control algorithm to ensure that the harvester is always working on the oscillator's high energy attractor. (paper)

  14. A Novel Ropes-DrivenWideband Piezoelectric Vibration Energy Harvester

    Directory of Open Access Journals (Sweden)

    Jinhui Zhang

    2016-12-01

    Full Text Available This paper presents a novel piezoelectric vibration energy harvester (PVEH in which a high-frequency generating beam (HFGB is driven by an array of low-frequency driving beams (LFDBs using ropes. Two mechanisms based on frequency upconversion and multimodal harvesting work together to broaden the frequency bandwidth of the proposed vibration energy harvester (VEH. The experimental results show that the output power of generating beam (GB remains unchanged with the increasing number of driving beams (DBs, compared with the traditional arrays of beams vibration energy harvester (AB-VEH, and the output power and bandwidth behavior can be adjusted by parameters such as acceleration, rope margin, and stiffness of LFDBs, which shows the potential to achieve unlimited wideband vibration energy-harvesting for a variable environment.

  15. Timber harvesting patterns for major states in the central, northern, and mid-Atlantic hardwood regions

    Science.gov (United States)

    William G. Luppold; Matthew S. Bumgardner

    2018-01-01

    Timber harvesting is a major disturbance agent influencing the composition and structure of eastern hardwood forests. To better understand timber harvesting practices, we examined roundwood harvesting patterns in 13 eastern states in the Central, Mid-Atlantic, and Northern regions that contained high proportional volumes of hardwood in their forest inventories. Nearly...

  16. Radio Frequency Energy Harvesting Sources

    Directory of Open Access Journals (Sweden)

    Action NECHIBVUTE

    2017-12-01

    Full Text Available This radio frequency (RF energy harvesting is an emerging technology and research area that promises to produce energy to run low-power wireless devices. The great interest that has recently been paid to RF harvesting is predominantly driven by the great progress in both wireless communication systems and broadcasting technologies that have availed a lot of freely propagating ambient RF energy. The principle aim of an RF energy harvesting system is to convert the received ambient RF energy into usable DC power. This paper presents a state of the art concise review of RF energy harvesting sources for low power applications, and also discusses open research questions and future research directions on ambient RF energy harvesting.

  17. Timber harvest as the predominant disturbance regime in northeastern U.S. forests: Effects of harvest intensification

    Science.gov (United States)

    Brown, Michelle L.; Canham, Charles D.; Murphy, Lora; Donovan, Therese M.

    2018-01-01

    Harvesting is the leading cause of adult tree mortality in forests of the northeastern United States. While current rates of timber harvest are generally sustainable, there is considerable pressure to increase the contribution of forest biomass to meet renewable energy goals. We estimated current harvest regimes for different forest types and regions across the U.S. states of New York, Vermont, New Hampshire, and Maine using data from the U.S. Forest Inventory and Analysis Program. We implemented the harvest regimes in SORTIE‐ND, an individual‐based model of forest dynamics, and simulated the effects of current harvest regimes and five additional harvest scenarios that varied by harvest frequency and intensity over 150 yr. The best statistical model for the harvest regime described the annual probability of harvest as a function of forest type/region, total plot basal area, and distance to the nearest improved road. Forests were predicted to increase in adult aboveground biomass in all harvest scenarios in all forest type and region combinations. The magnitude of the increase, however, varied dramatically—increasing from 3% to 120% above current landscape averages as harvest frequency and intensity decreased. The variation can be largely explained by the disproportionately high harvest rates estimated for Maine as compared with the rest of the region. Despite steady biomass accumulation across the landscape, stands that exhibited old‐growth characteristics (defined as ≥300 metric tons of biomass/hectare) were rare (8% or less of stands). Intensified harvest regimes had little effect on species composition due to widespread partial harvesting in all scenarios, resulting in dominance by late‐successional species over time. Our analyses indicate that forest biomass can represent a sustainable, if small, component of renewable energy portfolios in the region, although there are tradeoffs between carbon sequestration in forest biomass and sustainable

  18. Piezoelectric energy harvesting through shear mode operation

    International Nuclear Information System (INIS)

    Malakooti, Mohammad H; Sodano, Henry A

    2015-01-01

    Piezoelectric materials are excellent candidates for use in energy harvesting applications due to their high electromechanical coupling properties that enable them to convert input mechanical energy into useful electric power. The electromechanical coupling coefficient of the piezoelectric material is one of the most significant parameters affecting energy conversion and is dependent on the piezoelectric mode of operation. In most piezoceramics, the d 15 piezoelectric shear coefficient is the highest coefficient compared to the commonly used axial and transverse modes that utilize the d 33 and the d 31 piezoelectric strain coefficients. However, complicated electroding methods and challenges in evaluating the performance of energy harvesting devices operating in the shear mode have slowed research in this area. The shear deformation of a piezoelectric layer can be induced in a vibrating sandwich beam with a piezoelectric core. Here, a model based on Timoshenko beam theory is developed to predict the electric power output from a cantilever piezoelectric sandwich beam under base excitations. It is shown that the energy harvester operating in the shear mode is able to generate ∼50% more power compared to the transverse mode for a numerical case study. Reduced models of both shear and transverse energy harvesters are obtained to determine the optimal load resistance in the system and perform an efficiency comparison between two models with fixed and adaptive resistances. (paper)

  19. Harvesting a short rotation forest

    Energy Technology Data Exchange (ETDEWEB)

    Perttu, K L [ed.

    1984-12-01

    Willow and Sallow, considered of great interest for Swedish conditions, present new problems in harvesting. Traditional logging techniques offer few elements of equipment or methods. Light whips may be comminuted to a bulk product, easy to handle, difficult to store, requiring a hot logging system - and requiring a heavy, powerful harvester. Aggregating the material introduces an intermediate wood-fuel unit, suitable for storing, transport and infeed into any comminuter. If the harvester produced billets it would require less energy for its operation and it may be used for other purposes such as pre-commercial thinning or row thinning during the growing season. A few groups of designers have worked on analyses of requirements and possible solutions. Test rigs for severing and bundling were built and evaluated. Public funding was made available for design work on harvesters. Five groups were selected to produce layout designs of large and small harvesters. An evaluation procedure was performed, leading to selection of two concepts, slightly reworked from their original shapes. One is a large self-propelled front-sutting harvester, the other is a harvesting unit to be mounted on a suitable farm tractor. With 3 refs.

  20. High-concentrate diets based on forages harvested at different maturity stages affect ruminal synthesis of B vitamins in lactating dairy cows.

    Science.gov (United States)

    Castagnino, D S; Kammes, K L; Allen, M S; Gervais, R; Chouinard, P Y; Girard, C L

    2017-04-01

    Effects of plant maturity on apparent ruminal synthesis and post-ruminal supply of B vitamins were evaluated in two feeding trials. Diets containing alfalfa (Trial 1) or orchardgrass (Trial 2) silages harvested either (1) early cut, less mature (EC) or (2) late cut, more mature (LC) as the sole forage were offered to ruminally and duodenally cannulated lactating Holstein cows in crossover design experiments. In Trial 1, conducted with 16 cows (569±43 kg of empty BW (ruminal content removed) and 43.7±8.6 kg/day of 3.5% fat-corrected milk yield; mean±SD) in two 17-day treatment periods, both diets provided ~22% forage NDF and 27% total NDF, and the forage-to-concentrate ratios were 53 : 47 and 42 : 58 for EC and LC, respectively. In Trial 2, conducted with 13 cows (588±55 kg of empty BW and 43.7±7.7 kg/day of 3.5% fat-corrected milk yield; mean±SD) in two 18-day treatment periods, both diets provided ~25% forage NDF and 31% total NDF; the forage-to-concentrate ratios were 58 : 42 and 46 : 54 for EC and LC, respectively. Thiamin, riboflavin, niacin, vitamin B6, folates and vitamin B12 were measured in feed and duodenal content. Apparent ruminal synthesis was calculated as the duodenal flow minus the intake. Diets based on EC alfalfa decreased the amounts of thiamin, niacin and folates reaching the duodenum, whereas diets based on EC orchardgrass increased riboflavin duodenal flow. Daily apparent ruminal synthesis of thiamin, riboflavin, niacin and vitamin B6 were correlated negatively with their intake, suggesting a microbial regulation of their concentration in the rumen. Vitamin B12 apparent ruminal synthesis was correlated negatively with total volatile fatty acids concentration, but positively with ruminal pH and microbial N duodenal flow.

  1. A bountiful spring harvest

    CERN Multimedia

    2013-01-01

    Although we recently put the clocks forward and spring has officially begun, the view from my window looks more autumnal – befitting of the season of mists and mellow fruitfulness, rather than that of sowing seeds for the future. Which, in a way is appropriate. With the LHC paused, we are reaping a kind of harvest in the form of recognition for our efforts.   Two weeks ago, I was in Edinburgh, on behalf of everyone at CERN, to collect the Edinburgh medal, which we shared with Peter Higgs. I particularly like the citation for this honour: “The Edinburgh Medal is awarded each year to men and women of science and technology whose professional achievements are judged to have made a significant contribution to the understanding and well-being of humanity.” I like this, because it underlines a fact that needs to be shouted louder – that fundamental science does more than build the sum of human knowledge, it is also the foundation of human well-being. A few d...

  2. Preliminary design of a coffee harvester

    Directory of Open Access Journals (Sweden)

    Raphael Magalhães Gomes Moreira

    2016-10-01

    Full Text Available Design of an agricultural machine is a highly complex process due to interactions between the operator, machine, and environment. Mountain coffee plantations constitute an economic sector that requires huge investments for the development of agricultural machinery to improve the harvesting and post-harvesting processes and to overcome the scarcity of work forces in the fields. The aim of this study was to develop a preliminary design for a virtual prototype of a coffee fruit harvester. In this study, a project methodology was applied and adapted for the development of the following steps: project planning, informational design, conceptual design, and preliminary design. The construction of a morphological matrix made it possible to obtain a list of different mechanisms with specific functions. The union between these mechanisms resulted in variants, which were weighed to attribute scores for each selected criterion. From each designated proposal, two variants with the best scores were selected and this permitted the preparation of the preliminary design of both variants. The archetype was divided in two parts, namely the hydraulically articulated arms and the harvesting system that consisted of the vibration mechanism and the detachment mechanism. The proposed innovation involves the use of parallel rods, which were fixed in a plane and rectangular metal sheet. In this step, dimensions including a maximum length of 4.7 m, a minimum length of 3.3 m, and a total height of 2.15 m were identified based on the functioning of the harvester in relation to the coupling point of the tractor.

  3. Mechanical harvesting of pumpkin seeds

    OpenAIRE

    Sito, Stjepan; Ivančan, Stjepan; Barković, Edi; Mucalo, Ana

    2009-01-01

    One of the key problems in production technology of pumpkin seed for oil production is mechanized harvesting and losses of seed during mechanical harvesting. The losses of pumpkin seed during mechanical harvesting at peripheral velocity of 1.57 m/s (optimally adjusted machine) were 4.4% for Gleisdorf species, 5.2% for Slovenska species and 7.8% for pumpkin with husk. The higher average losses of pumpkin seed with husk were caused by tight connection of seed and pumpkin fruit.

  4. Performance of a piezoelectric energy harvester in actual rain

    International Nuclear Information System (INIS)

    Wong, Voon-Kean; Ho, Jee-Hou; Chai, Ai-Bao

    2017-01-01

    When raindrops impact on the surface of a piezoelectric beam, strain energy produced by the impinging raindrop will be converted to harvestable electrical energy by the piezoelectric layers in a cantilever beam. The novelty of this study is to investigate the performance of the harvester in actual rain and provide practical insights on implementation. The influences of rain parameters such as rain rate, rainfall depth, raindrop count, and drop size distribution (DSD) are discussed in this study. The raindrops accumulated on the surface of the piezoelectric beam will form a water layer. It is described using added mass coefficient in this study. In an actual rain experiment, a piezoelectric beam with surface area of 0.0018 m 2 is able to produce 2076 μJ of energy over a duration of 301 min. The energy generation of a raindrop impact piezoelectric energy harvester is highly dependent on the rain rate. Due to the inconsistency of the energy generation, the piezoelectric energy harvester would require an integration of suitable energy storage device for continuous operation. Nevertheless, this work shows the feasibility of harvesting raindrop energy using a piezoelectric beam. - Highlights: • The performance of a piezoelectric rain energy harvester is tested in actual rain. • The energy generation is highly dependent on the rain rate. • Practical insights on the implementation of the harvester are discussed. • A total energy of 2076 μJ is generated over a duration of 301 min.

  5. Controlling Light Harvesting with Light

    NARCIS (Netherlands)

    Gwizdala, M.S.; Berera, R.; Kirilovsky, D.; van Grondelle, R.; Kruger, T.P.J.

    2016-01-01

    When exposed to intense sunlight, all organisms performing oxygenic photosynthesis implement various photoprotective strategies to prevent potentially lethal photodamage. The rapidly responding photoprotective mechanisms, occurring in the light-harvesting pigment-protein antennae, take effect within

  6. Magnetic Nanocomposite Cilia Energy Harvester

    KAUST Repository

    Khan, Mohammed Asadullah

    2016-02-11

    An energy harvester capable of converting low frequency vibrations into electrical energy is presented. The operating principle, fabrication process and output characteristics at different frequencies are discussed. The harvester is realized by fabricating an array of polydimethylsiloxane (PDMS) - iron nanowire nanocomposite cilia on a planar coil array. Each coil element consists of 14 turns and occupies an area of 600 μm x 600μm. The cilia are arranged in a 12x5 array and each cilium is 250 μm wide and 2 mm long. The magnetic characteristics of the fabricated cilia indicate that the nanowires are well aligned inside of the nanocomposite, increasing the efficiency of energy harvesting. The energy harvester occupies an area of 66.96 mm2 and produces an output r.m.s voltage of 206.47μV, when excited by a 40 Hz vibration of 1 mm amplitude.

  7. Energy harvesting on highway bridges.

    Science.gov (United States)

    2011-01-01

    A concept for harvesting energy from the traffic-induced loadings on a highway bridge using piezoelectric : materials to generate electricity was explored through the prototype stage. A total of sixteen lead-zirconate : titanate (PZT) Type 5A piezoel...

  8. Harvester operator learnig efficiency analysis

    OpenAIRE

    Malovrh, Špela; Košir, Boštjan; Krč, Janez

    2004-01-01

    The article considers the possibilities of training future harvester operators. The course of learning with a simulator is described and analysed on the first such example in Slovenia. The times of individual processes are measured in two candidates. The paper describes the operation of a learning simulator for work on the harvester Timberjack 1270 D and the proceedings of aone-week course. A comparison between candidates regarding the consumption oftime and number of damages to the virtual m...

  9. Charge state distribution of ^{86}Kr in hydrogen and helium gas charge strippers at 2.7  MeV/nucleon

    Directory of Open Access Journals (Sweden)

    H. Kuboki

    2014-12-01

    Full Text Available The charge state distributions of krypton (^{86}Kr with an energy of 2.7  MeV/nucleon were measured using hydrogen (H_{2} and helium (He gas charge strippers. A differential pumping system was constructed to confine H_{2} and He gases to a thickness sufficient for the charge state distributions to attain equilibrium. The mean charge states of ^{86}Kr in H_{2} and He gases attained equilibrium at 25.1 and 23.2, respectively, whereas the mean charge state in N_{2} gas at equilibrium was estimated to be less than 20. The charge distributions are successfully reproduced by the cross sections of ionization and electron capture processes optimized by a fitting procedure.

  10. Harvesting of Dunaliella salina by membrane filtration at pilot scale

    KAUST Repository

    Monte, Joana

    2017-09-02

    The microalgae Dunaliella salina is industrially produced due to its high content in carotenoids induced by low nitrogen and high salinity conditions. D. salina with low carotenoids content also produces other added value compounds, however its recovery have hardly been studied. This work aims to examine the potential of pre-concentrating D. salina by membrane processing prior to a final harvesting step by low-shear centrifugation. The aim is to minimize the overall energy expenditure and reduce capital costs, while assuring a minimal loss of cell integrity. This task is challenging, considering the sensitivity of D. salina to shear. Harvesting of D. salina by ultrafiltration allowed reaching a final concentration factor of 5.9, with an average permeate flux of 31 L/(m2 h). The Total Cost of Ownership and energy consumption for harvesting are respectively 52% and 45% lower when applying a two-step approach with pre-concentration (ultrafiltration) compared to only harvesting by centrifugation.

  11. Harvesting of Dunaliella salina by membrane filtration at pilot scale

    KAUST Repository

    Monte, Joana; Sá , Marta; Galinha, Clá udia F.; Costa, Luí s; Hoekstra, Herre; Brazinha, Carla; Crespo, Joã o G.

    2017-01-01

    The microalgae Dunaliella salina is industrially produced due to its high content in carotenoids induced by low nitrogen and high salinity conditions. D. salina with low carotenoids content also produces other added value compounds, however its recovery have hardly been studied. This work aims to examine the potential of pre-concentrating D. salina by membrane processing prior to a final harvesting step by low-shear centrifugation. The aim is to minimize the overall energy expenditure and reduce capital costs, while assuring a minimal loss of cell integrity. This task is challenging, considering the sensitivity of D. salina to shear. Harvesting of D. salina by ultrafiltration allowed reaching a final concentration factor of 5.9, with an average permeate flux of 31 L/(m2 h). The Total Cost of Ownership and energy consumption for harvesting are respectively 52% and 45% lower when applying a two-step approach with pre-concentration (ultrafiltration) compared to only harvesting by centrifugation.

  12. Performance evaluation of prototype mechanical cassava harvester ...

    African Journals Online (AJOL)

    Large-scale cassava harvesting, especially during the dry season, is a major constraint to its industrial demand and commercial production. Manual harvesting is slow and ... Results from field trials showed prototype harvesters weighing 268 – 310 kg can achieve optimum performance on ridged landforms. When harvested ...

  13. Still special? Harvesting procedures for industrial hemp

    Directory of Open Access Journals (Sweden)

    Hans-Jörg Gusovius

    2016-01-01

    Full Text Available A multitude of different harvesting procedures is available after the re-approval of hemp growing in Germany about 20 years ago. Established, but as well recent machine developments enable the supply of raw materials for further processing or as food and feed materials. The necessary specialization level results in high but, compared to other established crops, not exceeding procedural costs. In this study, harvesting procedures and technologies are analyzed that are currently used under Northern European cultivation conditions. However, technological enhancements are still needed in order to improve the competitiveness of fibre hemp in the crop rotation as well as of hemp-based semi-finished and finished products.

  14. Risk Analysis Approach to Rainwater Harvesting Systems

    Directory of Open Access Journals (Sweden)

    Nadia Ursino

    2016-08-01

    Full Text Available Urban rainwater reuse preserves water resources and promotes sustainable development in rapidly growing urban areas. The efficiency of a large number of urban water reuse systems, operating under different climate and demand conditions, is evaluated here on the base of a new risk analysis approach. Results obtained by probability analysis (PA indicate that maximum efficiency in low demanding scenarios is above 0.5 and a threshold, distinguishing low from high demanding scenarios, indicates that in low demanding scenarios no significant improvement in performance may be attained by increasing the storage capacity of rainwater harvesting tanks. Threshold behaviour is displayed when tank storage capacity is designed to match both the average collected volume and the average reuse volume. The low demand limit cannot be achieved under climate and operating conditions characterized by a disproportion between harvesting and demand volume.

  15. The start of the harvest

    CERN Multimedia

    2011-01-01

    The first major particle physics summer conference has just started this week in Grenoble. After the Quark-Matter conference, the Europhysics Conference on High-Energy Physics marks the start of a promising harvest for the LHC experiments.   For the first time, the collaborations will be presenting their latest results based on all luminosity taken until end of June, which will provide more precise measurements in many areas. Thanks to the excellent performance of the LHC, the experiments have already accumulated a substantial quantity of data allowing them to push back the known limits and refine measurements in many fields ranging from b physics to the search for the Higgs boson and for dark matter. At the time of writing, the LHC collaborations are about to present these new results in an energy range which has never previously been explored. I have congratulated all the teams involved in getting the LHC into operation in record time with great efficiency. Today I would like to acknowledge the...

  16. Centralised urban stormwater harvesting for potable reuse.

    Science.gov (United States)

    McArdle, P; Gleeson, J; Hammond, T; Heslop, E; Holden, R; Kuczera, G

    2011-01-01

    Urban impervious areas provide a guaranteed source of runoff, especially in cities with high rainfall - this represents a source of water with low sensitivity to unfavourable climate change. Whilst the potential to reuse stormwater has long been recognised, its quality has largely limited usage to non-potable applications requiring the use of a third-pipe network, a prohibitively expensive option in established urban areas. Given recent advances in membrane filtration, this study investigates the potential of harvesting and treating stormwater to a potable standard to enable use of the potable distribution network. A case study based on the Throsby Creek catchment in Newcastle explores the issue. The high seasonally uniform rainfall provides insight into the maximum potential of such an option. Multicriterion optimisation was used to identify Pareto optimal solutions for harvesting, storing and treating stormwater. It is shown that harvesting and treating stormwater from a 13 km² catchment can produce yields ranging from 8.5 to 14.2 ML/day at costs ranging from AU$2.60/kL to AU$2.89/kL, which may become viable as the cost of traditional supply continues to grow. However, there are significant social impacts to deal with including alienation of public land for storage and community acceptance of treated stormwater.

  17. A high charge state heavy ion beam source for HIF

    International Nuclear Information System (INIS)

    Eylon, S.; Henestroza, E.

    1995-04-01

    A high current low emittance high charge state heavy ion beam source is being developed. This is designed to deliver HIF (heavy ion fusion) driver accelerator scale beam. Using high-charge-state beam in a driver accelerator for HIF may increase the acceleration efficiency, leading to a reduction in the driver accelerator size and cost. The proposed source system which consists of the gas beam electron stripper followed by a high charge state beam separator, can be added to existing single charge state, low emittance, high brightness ion sources and injectors. We shall report on the source physics design using 2D beam envelope simulations and experimental feasibility studies' results using a neutral gas stripper and a beam separator at the exit of the LBL 2 MV injector

  18. heteroHarvest: Harvesting Information from Heterogeneous Sources

    DEFF Research Database (Denmark)

    Qureshi, Pir Abdul Rasool; Memon, Nasrullah; Wiil, Uffe Kock

    2011-01-01

    The abundance of information regarding any topic makes the Internet a very good resource. Even though searching the Internet is very easy, what remains difficult is to automate the process of information extraction from the available online information due to the lack of structure and the diversity...... in the sharing methods. Most of the times, information is stored in different proprietary formats, complying with different standards and protocols which makes tasks like data mining and information harvesting very difficult. In this paper, an information harvesting tool (heteroHarvest) is presented...... with objectives to address these problems by filtering the useful information and then normalizing the information in a singular non hypertext format. Finally we describe the results of experimental evaluation. The results are found promising with an overall error rate equal to 6.5% across heterogeneous formats....

  19. A Hip Implant Energy Harvester

    Science.gov (United States)

    Pancharoen, K.; Zhu, D.; Beeby, S. P.

    2014-11-01

    This paper presents a kinetic energy harvester designed to be embedded in a hip implant which aims to operate at a low frequency associated with body motion of patients. The prototype is designed based on the constrained volume available in a hip prosthesis and the challenge is to harvest energy from low frequency movements (< 1 Hz) which is an average frequency during free walking of a patient. The concept of magnetic-force-driven energy harvesting is applied to this prototype considering the hip movements during routine activities of patients. The magnetic field within the harvester was simulated using COMSOL. The simulated resonant frequency was around 30 Hz and the voltage induced in a coil was predicted to be 47.8 mV. A prototype of the energy harvester was fabricated and tested. A maximum open circuit voltage of 39.43 mV was obtained and the resonant frequency of 28 Hz was observed. Moreover, the power output of 0.96 μW was achieved with an optimum resistive load of 250Ω.

  20. A Hip Implant Energy Harvester

    International Nuclear Information System (INIS)

    Pancharoen, K; Zhu, D; Beeby, S P

    2014-01-01

    This paper presents a kinetic energy harvester designed to be embedded in a hip implant which aims to operate at a low frequency associated with body motion of patients. The prototype is designed based on the constrained volume available in a hip prosthesis and the challenge is to harvest energy from low frequency movements (< 1 Hz) which is an average frequency during free walking of a patient. The concept of magnetic-force-driven energy harvesting is applied to this prototype considering the hip movements during routine activities of patients. The magnetic field within the harvester was simulated using COMSOL. The simulated resonant frequency was around 30 Hz and the voltage induced in a coil was predicted to be 47.8 mV. A prototype of the energy harvester was fabricated and tested. A maximum open circuit voltage of 39.43 mV was obtained and the resonant frequency of 28 Hz was observed. Moreover, the power output of 0.96 μW was achieved with an optimum resistive load of 250Ω

  1. Hybrid Nanogenerator for Concurrently Harvesting Biomechanical and Biochemical Energy

    KAUST Repository

    Hansen, Benjamin J.

    2010-07-27

    Harvesting energy from multiple sources available in our personal and daily environments is highly desirable, not only for powering personal electronics, but also for future implantable sensor-transmitter devices for biomedical and healthcare applications. Here we present a hybrid energy scavenging device for potential in vivo applications. The hybrid device consists of a piezoelectric poly(vinylidene fluoride) nanofiber nanogenerator for harvesting mechanical energy, such as from breathing or from the beat of a heart, and a flexible enzymatic biofuel cell for harvesting the biochemical (glucose/O2) energy in biofluid, which are two types of energy available in vivo. The two energy harvesting approaches can work simultaneously or individually, thereby boosting output and lifetime. Using the hybrid device, we demonstrate a "self-powered" nanosystem by powering a ZnO nanowire UV light sensor. © 2010 American Chemical Society.

  2. Designs for thermal harvesting with nonlinear coordinate transformation

    Science.gov (United States)

    Ji, Qingxiang; Fang, Guodong; Liang, Jun

    2018-04-01

    In this paper a thermal concentrating design method was proposed based on the concept of generating function without knowing the needed coordinate transformation beforehand. The thermal harvesting performance was quantitatively characterized by heat concentrating efficiency and external temperature perturbation. Nonlinear transformations of different forms were employed to design high order thermal concentrators, and corresponding harvesting performances were investigated by numerical simulations. The numerical results shows that the form of coordinate transformation directly influences the distributions of heat flows inside the concentrator, consequently, influences the thermal harvesting behaviors significantly. The concentrating performance can be actively controlled and optimized by changing the form of coordinate transformations. The analysis in this paper offers a beneficial method to flexibly tune the harvesting performance of the thermal concentrator according to the requirements of practical applications.

  3. Effect of harvest date on the nutritional quality and antioxidant capacity in 'Hass' avocado during storage.

    Science.gov (United States)

    Wang, Meng; Zheng, Yusheng; Khuong, Toan; Lovatt, Carol J

    2012-11-15

    The effect of harvest date on nutritional compounds and antioxidant activity (AOC) in avocado (Persea americana Mill. cv Hass) fruit during storage was determined. The fruits were harvested at seven different dates and ripened at 25 °C following 21 or 35 days of cold storage. The results indicated that the phenolic and glutathione contents were increased and the ascorbic acid content was not significantly different in early harvested fruit (January to March), and the phenolic, ascorbic acid and glutathione contents were increased slightly and then decreased on late harvested fruit (April to June). Similar trends were observed in the changes of AOC. Furthermore, AOC in early harvested fruit after storage for 35 days was much higher than that in late harvested fruit after storage for 21 days. Therefore, avocado can be harvested earlier for economic benefits according to the market and can keep high nutritional value for human health benefits. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Mechanization in firewood harvesting in southern Italy

    Directory of Open Access Journals (Sweden)

    2005-01-01

    Full Text Available The aim of this research was to survey current mechanization level of coppice harvesting in Southern Italy. The cooperation of the General Direction of the National Forest Service (NFS has been a basic tool of survey. A questionnaire compiled on purpose was sent to each Forest Station (hereinafter referred to as CS in the following regions: Basilicata, Campania and Calabria. A high percentage (80% of the CSs did fulfill the questionnaire. The answers highlight that: i the main assortment currently produced is firewood; ii the level of harvesting mechanization is rather low, equipment being quite obsolete: indeed, the most widely used machineries are farm tractors partly adapted to forest harvesting and equipped with cages or back winch; iii the use of animals for hauling (mules and oxen, the latter in Calabria is still quite frequent, while forest tractors, polyethylene chutes and cable cranes are almost absent; iv the use of individual protection (DPI and machinery protection devices (DPM is on average quite low.

  5. Performance Limits of Communication with Energy Harvesting

    KAUST Repository

    Znaidi, Mohamed Ridha

    2016-04-01

    In energy harvesting communications, the transmitters have to adapt transmission to the availability of energy harvested during communication. The performance of the transmission depends on the channel conditions which vary randomly due to mobility and environmental changes. During this work, we consider the problem of power allocation taking into account the energy arrivals over time and the quality of channel state information (CSI) available at the transmitter, in order to maximize the throughput. Differently from previous work, the CSI at the transmitter is not perfect and may include estimation errors. We solve this problem with respect to the energy harvesting constraints. Assuming a perfect knowledge of the CSI at the receiver, we determine the optimal power policy for different models of the energy arrival process (offline and online model). Indeed, we obtain the power allocation scheme when the transmitter has either perfect CSI or no CSI. We also investigate of utmost interest the case of fading channels with imperfect CSI. Moreover, a study of the asymptotic behavior of the communication system is proposed. Specifically, we analyze of the average throughput in a system where the average recharge rate goes asymptotically to zero and when it is very high.

  6. THE BEHAVIORAL PROFILE OF HARVESTER OPERATORS

    Directory of Open Access Journals (Sweden)

    Millana Burger Pagnussat

    Full Text Available ABSTRACT This study aims to characterize the behavioral profile of harvester operators, with the goal of assisting forest managers in selecting and training new teams of employees. A forest company located in central-western Brazil was examined from a sample of 20 harvester operators that did not have experience carrying out the functions of their industry. A behavioral profile evaluation tool was used, consisting of a management system that creates a profile based on behavioral competencies; it was initially used to develop a profile of a high-performing harvester operator; or rather, a reference profile. Next, the behavioral profile of the operators were grouped into distinct classes and compared with the reference profile to identify traits that could positively or negatively affect an operators' performance. An optimal profile had the following qualities: attentive to details, meets deadlines and follows rules, technically-oriented, patient with repetitive tasks, the ability to avoid conflicts, and being an introvert. An improper profile included aspects such as aggressiveness, being argumentative, being persuasive, explosive, and tense at work. The behavioral profile evaluation tool can support the process of choosing forest machine operators; however, it is important to also consider skills and work experience.

  7. Experimental study of energy harvesting in UHF band

    International Nuclear Information System (INIS)

    Bernacki, Ł; Gozdur, R; Salamon, N

    2016-01-01

    A huge progress of down-sizing technology together with trend of decreasing power consumption and, on the other hand, increasing efficiency of electronics give the opportunity to design and to implement the energy harvesters as main power sources. This paper refers to the energy that can be harvested from electromagnetic field in the unlicensed frequency bands. The paper contains description of the most popular techniques and transducers that can be applied in energy harvesting domain. The overview of current research and commercial solutions was performed for bands in ultra-high frequency range, which are unlicensed and where transmission is not limited by administrative arrangements. During the experiments with Powercast’s receiver, the same bands as sources of electromagnetic field were taken into account. This power source is used for conducting radio-communication process and excess energy could be used for powering the extra electronic circuits. The paper presents elaborated prototype of energy harvesting system and the measurements of power harvested in ultra-high frequency range. The evaluation of RF energy harvesters for powering ultra-low power (ULP) electronic devices was performed based on survey and results of the experiments. (paper)

  8. Pen harvester for powering a pulse rate sensor

    International Nuclear Information System (INIS)

    Bedekar, Vishwas; Oliver, Josiah; Priya, Shashank

    2009-01-01

    Rapid developments in the area of micro-sensors for various applications such as structural health monitoring, bio-chemical sensors and pressure sensors have increased the demand for portable, low cost, high efficiency energy harvesting devices. In this paper, we describe the scheme for powering a pulse rate sensor with a vibration energy harvester integrated inside a pen commonly carried by humans in the pocket close to the heart. Electromagnetic energy harvesting was selected in order to achieve high power at lower frequencies. The prototype pen harvester was found to generate 3 mW at 5 Hz and 1 mW at 3.5 Hz operating under displacement amplitude of 16 mm (corresponding to an acceleration of approximately 1.14 g rms at 5 Hz and 0.56 g rms at 3.5 Hz, respectively). A comprehensive mathematical modelling and simulations were performed in order to optimize the performance of the vibration energy harvester. The integrated pen harvester prototype was found to generate continuous power of 0.46-0.66 mW under normal human actions such as jogging and jumping which is enough for a small scale pulse rate sensor.

  9. Computer Vision for Timber Harvesting

    DEFF Research Database (Denmark)

    Dahl, Anders Lindbjerg

    The goal of this thesis is to investigate computer vision methods for timber harvesting operations. The background for developing computer vision for timber harvesting is to document origin of timber and to collect qualitative and quantitative parameters concerning the timber for efficient harvest...... segments. The purpose of image segmentation is to make the basis for more advanced computer vision methods like object recognition and classification. Our second method concerns image classification and we present a method where we classify small timber samples to tree species based on Active Appearance...... to the development of the logTracker system the described methods have a general applicability making them useful for many other computer vision problems....

  10. Cantilever piezoelectric energy harvester with multiple cavities

    International Nuclear Information System (INIS)

    S Srinivasulu Raju; M Umapathy; G Uma

    2015-01-01

    Energy harvesting employing piezoelectric materials in mechanical structures such as cantilever beams, plates, diaphragms, etc, has been an emerging area of research in recent years. The research in this area is also focused on structural tailoring to improve the harvested power from the energy harvesters. Towards this aim, this paper presents a method for improving the harvested power from a cantilever piezoelectric energy harvester by introducing multiple rectangular cavities. A generalized model for a piezoelectric energy harvester with multiple rectangular cavities at a single section and two sections is developed. A method is suggested to optimize the thickness of the cavities and the number of cavities required to generate a higher output voltage for a given cantilever beam structure. The performance of the optimized energy harvesters is evaluated analytically and through experimentation. The simulation and experimental results show that the performance of the energy harvester can be increased with multiple cavities compared to the harvester with a single cavity. (paper)

  11. Biogeography of photosynthetic light-harvesting genes in marine phytoplankton.

    Directory of Open Access Journals (Sweden)

    Thomas S Bibby

    Full Text Available BACKGROUND: Photosynthetic light-harvesting proteins are the mechanism by which energy enters the marine ecosystem. The dominant prokaryotic photoautotrophs are the cyanobacterial genera Prochlorococcus and Synechococcus that are defined by two distinct light-harvesting systems, chlorophyll-bound protein complexes or phycobilin-bound protein complexes, respectively. Here, we use the Global Ocean Sampling (GOS Project as a unique and powerful tool to analyze the environmental diversity of photosynthetic light-harvesting genes in relation to available metadata including geographical location and physical and chemical environmental parameters. METHODS: All light-harvesting gene fragments and their metadata were obtained from the GOS database, aligned using ClustalX and classified phylogenetically. Each sequence has a name indicative of its geographic location; subsequent biogeographical analysis was performed by correlating light-harvesting gene budgets for each GOS station with surface chlorophyll concentration. CONCLUSION/SIGNIFICANCE: Using the GOS data, we have mapped the biogeography of light-harvesting genes in marine cyanobacteria on ocean-basin scales and show that an environmental gradient exists in which chlorophyll concentration is correlated to diversity of light-harvesting systems. Three functionally distinct types of light-harvesting genes are defined: (1 the phycobilisome (PBS genes of Synechococcus; (2 the pcb genes of Prochlorococcus; and (3 the iron-stress-induced (isiA genes present in some marine Synechococcus. At low chlorophyll concentrations, where nutrients are limited, the Pcb-type light-harvesting system shows greater genetic diversity; whereas at high chlorophyll concentrations, where nutrients are abundant, the PBS-type light-harvesting system shows higher genetic diversity. We interpret this as an environmental selection of specific photosynthetic strategy. Importantly, the unique light-harvesting system isiA is found

  12. Harvest of table olives by mechanical harvesting equipment

    Directory of Open Access Journals (Sweden)

    Filippo Gambella

    2013-09-01

    Full Text Available In this work, we have evaluated the performance, of an electric comb equipped with five undulated fingers used for mechanized the harvesting of table olives. The first aim of the work was to test three different types of coating materials used for covering the fingers: Silicon (S, Vulcanized rubber (VR and Natural rubber (NR. The diameter of the coating materials tested were 7mm (D1, 14 mm (D2, 19 mm (D3 in order to evaluate the damage of different working conditions on the intact olives. During harvesting, silicon at 7mm and 14mm resulted in the largest percentage of undamaged the fruit (67% and 65%, natural rubber 63% and vulcanized rubber at the 54%. The second aim was to evaluate the combination, in terms of the best performance, of the machines used for mechanized harvesting of table olives. Several factors have been examined: undulating fingers variation thickness, different rotational speeds and different coating materials used to reduce the impact damage on olives. From the tests on olive tree we have determined that while plastic materials (S and (NR appear to have a positive role in harvest quality, the vibration transmitted to the operator’s hand is great from 6.48 m/s2 for S to 6.31 m/ s2 for NR and 2.92 m/s2 for VR, respect to the materials used.

  13. Pine Harvest Impact on Soil Structure of a Dystric Cambisol (Humic

    Directory of Open Access Journals (Sweden)

    Adriano da Costa

    2016-01-01

    Full Text Available ABSTRACT Traffic of heavy machinery at harvest and log extraction causes structural degradation of the soil, but studies on the effects of forest harvesting on soils with high organic matter content and exchangeable Al are scarce. The objective of this study was to evaluate the effect of mechanized forest harvesting operations on a Dystric Cambisol (Humic with high organic matter (more 50 g kg1 content and exchangeable Al (more 6,0 cmolc kg-1, reforested with Pinus taeda L. The evaluated harvesting system were the whole-tree, in which the feller-buncher cuts and lays the trees down in bundles; the skidder drags the tree bundles up near a road; and the harvester delimbs and cuts the trees into short logs, stacking them on the roadside to be loaded onto trucks. The areas were evaluated for soil conditions at pre-harvest, prior to harvest, and at post-harvest, consisting of areas of low disturbance, high disturbance, forest residues and log yards. The effects of compaction after forest harvesting are observed by the decrease in total porosity (especially biopores and macropores, soil saturated hydraulic conductivity, and stability of aggregates. After forest harvesting, soil compaction was observed in all evaluated situations, but with different depths depending on operation type and the intensity of traffic carried in each area.

  14. Do biomass harvesting guidelines influence herpetofauna following harvests of logging residues for renewable energy?.

    Science.gov (United States)

    Fritts, Sarah; Moorman, Christopher; Grodsky, Steven; Hazel, Dennis; Homyack, Jessica; Farrell, Chris; Castleberry, Steven

    2016-04-01

    were weak or absent. The lack of consistent community or population responses suggests the addition of a woody biomass harvest to a clearcut in pine plantations does not impact herpetofauna use of Coastal Plain loblolly plantations in the southeastern United States. We recommend additional research to examine relationships between woody biomass harvesting and rarer species or amphibians with high desiccation risk, particularly in other regions and harvesting systems.

  15. Modelling piezoelectric energy harvesting potential in an educational building

    International Nuclear Information System (INIS)

    Li, Xiaofeng; Strezov, Vladimir

    2014-01-01

    Highlights: • Energy harvesting potential of commercialized piezoelectric tiles is analyzed. • The parameters which will affect the energy harvesting efficiency are determined. • The potential could cover 0.5% of the total energy usage of the library building. • A simplified evaluation indicator is proposed to test the considered paving area. - Abstract: In this paper, potential application of a commercial piezoelectric energy harvester in a central hub building at Macquarie University in Sydney, Australia is examined and discussed. Optimization of the piezoelectric tile deployment is presented according to the frequency of pedestrian mobility and a model is developed where 3.1% of the total floor area with the highest pedestrian mobility is paved with piezoelectric tiles. The modelling results indicate that the total annual energy harvesting potential for the proposed optimized tile pavement model is estimated at 1.1 MW h/year. This potential energy generation may be further increased to 9.9 MW h/year with a possible improvement in piezoelectric energy conversion efficiency integrated into the system. This energy harvesting potential would be sufficient to meet close to 0.5% of the annual energy needs of the building. The study confirms that locating high traffic areas is critical for optimization of the energy harvesting efficiency, as well as the orientation of the tile pavement significantly affects the total amount of the harvested energy. A Density Flow evaluation is recommended in this study to qualitatively evaluate the piezoelectric power harvesting potential of the considered area based on the number of pedestrian crossings per unit time

  16. Energy harvesting from low frequency applications using piezoelectric materials

    International Nuclear Information System (INIS)

    Li, Huidong; Tian, Chuan; Deng, Z. Daniel

    2014-01-01

    In an effort to eliminate the replacement of the batteries of electronic devices that are difficult or impractical to service once deployed, harvesting energy from mechanical vibrations or impacts using piezoelectric materials has been researched over the last several decades. However, a majority of these applications have very low input frequencies. This presents a challenge for the researchers to optimize the energy output of piezoelectric energy harvesters, due to the relatively high elastic moduli of piezoelectric materials used to date. This paper reviews the current state of research on piezoelectric energy harvesting devices for low frequency (0–100 Hz) applications and the methods that have been developed to improve the power outputs of the piezoelectric energy harvesters. Various key aspects that contribute to the overall performance of a piezoelectric energy harvester are discussed, including geometries of the piezoelectric element, types of piezoelectric material used, techniques employed to match the resonance frequency of the piezoelectric element to input frequency of the host structure, and electronic circuits specifically designed for energy harvesters

  17. The role of energy losses in photosynthetic light harvesting

    Science.gov (United States)

    Krüger, T. P. J.; van Grondelle, R.

    2017-07-01

    Photosynthesis operates at the bottom of the food chain to convert the energy of light into carbohydrates at a remarkable global rate of about 130 TW. Nonetheless, the overall photosynthetic process has a conversion efficiency of a few percent at best, significantly less than bottom-up photovoltaic cells. The primary photosynthetic steps, consisting of light harvesting and charge separation, are often presented as having near-unity quantum efficiency but this holds only true under ideal conditions. In this review, we discuss the importance of energy loss mechanisms to establish robustness in photosynthetic light harvesting. Thermal energy dissipation of light-harvesting complexes (LHCs) in different environments is investigated and the relationships and contrasts between concentration quenching of high pigment concentrations, photoprotection (non-photochemical quenching), quenching due to protein aggregation, and fluorescence blinking are discussed. The role of charge-transfer states in light harvesting and energy dissipation is highlighted and the importance of controlled protein structural disorder to switch the light-harvesting antennae between effective light harvesters and efficient energy quenchers is underscored. The main LHC of plants, LHCII, is used as a prime example.

  18. The role of energy losses in photosynthetic light harvesting

    International Nuclear Information System (INIS)

    Krüger, T P J; Van Grondelle, R

    2017-01-01

    Photosynthesis operates at the bottom of the food chain to convert the energy of light into carbohydrates at a remarkable global rate of about 130 TW. Nonetheless, the overall photosynthetic process has a conversion efficiency of a few percent at best, significantly less than bottom-up photovoltaic cells. The primary photosynthetic steps, consisting of light harvesting and charge separation, are often presented as having near-unity quantum efficiency but this holds only true under ideal conditions. In this review, we discuss the importance of energy loss mechanisms to establish robustness in photosynthetic light harvesting. Thermal energy dissipation of light-harvesting complexes (LHCs) in different environments is investigated and the relationships and contrasts between concentration quenching of high pigment concentrations, photoprotection (non-photochemical quenching), quenching due to protein aggregation, and fluorescence blinking are discussed. The role of charge-transfer states in light harvesting and energy dissipation is highlighted and the importance of controlled protein structural disorder to switch the light-harvesting antennae between effective light harvesters and efficient energy quenchers is underscored. The main LHC of plants, LHCII, is used as a prime example. (topical review)

  19. A Shoe-Embedded Piezoelectric Energy Harvester for Wearable Sensors

    Directory of Open Access Journals (Sweden)

    Jingjing Zhao

    2014-07-01

    Full Text Available Harvesting mechanical energy from human motion is an attractive approach for obtaining clean and sustainable electric energy to power wearable sensors, which are widely used for health monitoring, activity recognition, gait analysis and so on. This paper studies a piezoelectric energy harvester for the parasitic mechanical energy in shoes originated from human motion. The harvester is based on a specially designed sandwich structure with a thin thickness, which makes it readily compatible with a shoe. Besides, consideration is given to both high performance and excellent durability. The harvester provides an average output power of 1 mW during a walk at a frequency of roughly 1 Hz. Furthermore, a direct current (DC power supply is built through integrating the harvester with a power management circuit. The DC power supply is tested by driving a simulated wireless transmitter, which can be activated once every 2–3 steps with an active period lasting 5 ms and a mean power of 50 mW. This work demonstrates the feasibility of applying piezoelectric energy harvesters to power wearable sensors.

  20. The highly efficient photocatalytic and light harvesting property of Ag-TiO2 with negative nano-holes structure inspired from cicada wings.

    Science.gov (United States)

    Zada, Imran; Zhang, Wang; Zheng, Wangshu; Zhu, Yuying; Zhang, Zhijian; Zhang, Jianzhong; Imtiaz, Muhammad; Abbas, Waseem; Zhang, Di

    2017-12-08

    The negative replica of biomorphic TiO 2 with nano-holes structure has been effectively fabricated directly from nano-nipple arrays structure of cicada wings by using a simple, low-cost and highly effective sol-gel ultrasonic method. The nano-holes array structure was well maintained after calcination in air at 500 °C. The Ag nanoparticles (10 nm-25 nm) were homogeneously decorated on the surface and to the side wall of nano-holes structure. It was observed that the biomorphic Ag-TiO 2 showed remarkable photocatalytic activity by degradation of methyl blue (MB) under UV-vis light irradiation. The biomorphic Ag-TiO 2 with nano-holes structure showed superior photocatalytic activity compared to the biomorphic TiO 2 and commercial Degussa P25. This high-performance photocatalytic activity of the biomorphic Ag-TiO 2 may be attributed to the nano-holes structure, localized surface plasmon resonance (LSPR) property of the Ag nanoparticles, and enhanced electron-hole separation. Moreover, the biomorphic Ag-TiO 2 showed more absorption capability in the visible wavelength range. This work provides a new insight to design such a structure which may lead to a range of novel applications.

  1. Post-harvest loss reduction

    NARCIS (Netherlands)

    Gogh, van Bart; Boerrigter, Henry; Noordam, Maryvon; Ruben, Ruerd; Timmermans, Toine

    2017-01-01

    This paper was written by experts from Wageningen University & Research (WUR), representing their combined expertise on food chains, post-harvest technology, sustainability, food security, economics, and food safety. The paper was drafted at the request of the Dutch Ministry of Economic Affairs

  2. Fluid flow nozzle energy harvesters

    Science.gov (United States)

    Sherrit, Stewart; Lee, Hyeong Jae; Walkemeyer, Phillip; Winn, Tyler; Tosi, Luis Phillipe; Colonius, Tim

    2015-04-01

    Power generation schemes that could be used downhole in an oil well to produce about 1 Watt average power with long-life (decades) are actively being developed. A variety of proposed energy harvesting schemes could be used to extract energy from this environment but each of these has their own limitations that limit their practical use. Since vibrating piezoelectric structures are solid state and can be driven below their fatigue limit, harvesters based on these structures are capable of operating for very long lifetimes (decades); thereby, possibly overcoming a principle limitation of existing technology based on rotating turbo-machinery. An initial survey [1] identified that spline nozzle configurations can be used to excite a vibrating piezoelectric structure in such a way as to convert the abundant flow energy into useful amounts of electrical power. This paper presents current flow energy harvesting designs and experimental results of specific spline nozzle/ bimorph design configurations which have generated suitable power per nozzle at or above well production analogous flow rates. Theoretical models for non-dimensional analysis and constitutive electromechanical model are also presented in this paper to optimize the flow harvesting system.

  3. Harvesting Cultural Knowledge.

    Science.gov (United States)

    Keating, Joseph F.

    1997-01-01

    Describes a year-long course called Outdoor Science taught at an American Indian reservation high school that demonstrates to students the connection between traditional tribal knowledge and western science to spark student interest in science. Presents a list that contains references on the subject of ethnobotany. Includes specific references for…

  4. Carbon Transfers and Emissions Following Harvest and Pile Burning in Coastal Douglas-fir Forests Determined from Analysis of High-Resolution UAV Imagery and Point Clouds and from Field Surveys.

    Science.gov (United States)

    Trofymow, J. A.; Gougeon, F.; Kelley, J. W.

    2017-12-01

    Forest carbon (C) models require knowledge on C transfers due to intense disturbances such as fire, harvest, and slash burning. In such events, live trees die and C transferred to detritus or exported as round wood. With burning, live and detrital C is lost as emissions. Burning can be incomplete, leaving wood, charred and scattered or in unburnt rings and piles. For harvests, all round wood volume is routinely measured, while dispersed and piled residue volumes are typically assessed in field surveys, scaled to a block. Recently, geospatial methods have been used to determine, for an entire block, piled residues using LiDAR or image point clouds (PC) and dispersed residues by analysis of high-resolution imagery. Second-growth Douglas-fir forests on eastern Vancouver Island were examined, 4 blocks at Oyster River (OR) and 2 at Northwest Bay (NB). OR blocks were cut winter 2011, piled spring 2011, field survey, aerial RGB imagery and LiDAR PC acquired fall 2011, piles burned, burn residues surveyed, and post-burn aerial RGB imagery acquired 2012. NB blocks were cut fall 2014, piled spring 2015, field survey, UAV RGB imagery and image PC acquired summer 2015, piles burned and burn residues surveyed spring 2016, and post-burn UAV RGB imagery and PC acquired fall 2016. Volume to biomass conversion used survey species proportions and wood density. At OR, round wood was 261.7 SE 13.1, firewood 1.7 SE 0.3, and dispersed residue by survey, 13.8 SE 3.6 tonnes dry mass (t dm) ha-1. Piled residues were 8.2 SE 0.9 from pile surveys vs. 25.0 SE 5.9 t dm ha-1 from LiDAR PC bulk pile volumes and packing ratios. Post-burn, piles lost 5.8 SE 0.5 from survey of burn residues vs. 18.2 SE 4.7 t dm ha-1 from pile volume changes using 2011 LiDAR PC and 2012 imagery. The percentage of initial merchantable biomass exported as round & fire wood, remaining as dispersed & piled residue, and lost to burning was, respectively, 92.5%, 5.5% and 2% using only field methods vs. 87%, 7% and 6% from

  5. High-resolution mapping of time since disturbance and forest carbon flux from remote sensing and inventory data to assess harvest, fire, and beetle disturbance legacies in the Pacific Northwest

    Directory of Open Access Journals (Sweden)

    H. Gu

    2016-11-01

    Full Text Available Accurate assessment of forest carbon storage and uptake is central to policymaking aimed at mitigating climate change and understanding the role forests play in the global carbon cycle. Disturbances have highly diverse impacts on forest carbon dynamics, making them a challenge to quantify and report. Time since disturbance is a key intermediate determinant that aids the assessment of disturbance-driven carbon emissions and removals legacies. We propose a new methodology of quantifying time since disturbance and carbon flux across forested landscapes in the Pacific Northwest (PNW at a fine scale (30 m by combining remote sensing (RS-based disturbance year, disturbance type, and above-ground biomass with forest inventory data. When a recent disturbance is detected, time since disturbance can be directly determined by combining three RS-derived disturbance products, or time since the last stand clearing can be inferred from a RS-derived 30 m biomass map and field inventory-derived species-specific biomass accumulation curves. Net ecosystem productivity (NEP is further mapped based on carbon stock and flux trajectories derived from the Carnegie-Ames-Stanford Approach (CASA model in our prior work that described how NEP changes with time following harvest, fire, or bark beetle disturbances of varying severity. Uncertainties from biomass map and forest inventory data were propagated by probabilistic sampling to provide a statistical distribution of stand age and NEP for each forest pixel. We mapped mean, standard deviation, and statistical distribution of stand age and NEP at 30 m in the PNW region. Our map indicated a net ecosystem productivity of 5.9 Tg C yr−1 for forestlands circa 2010 in the study area, with net uptake in relatively mature (> 24 years old forests (13.6 Tg C yr−1 overwhelming net negative NEP from tracts that had recent harvests (−6.4 Tg C yr−1, fires (−0.5 Tg C yr−1, and bark beetle

  6. Spring harvest of corn stover

    Energy Technology Data Exchange (ETDEWEB)

    Lizotte, P.L. [Laval Univ., Quebec City, PQ (Canada). Dept. des sols et de genie agroalimentaire; Savoie, P. [Agriculture and Agri-Food Canada, Quebec City, PQ (Canada)

    2010-07-01

    Corn stover is typically left behind in the field after grain harvest. Although part of the stover should remain in the field for soil organic matter renewal and erosion protection, half of the stover could be removed sustainably. This represents about one million t dry matter (DM) of stover per year in the province of Quebec. Stover harvested in the fall is very wet. While there are applications for wet stover, the available markets currently require a dry product. Preliminary measurements have shown that stover left in the field throughout the winter becomes very dry, and a considerable amount would still be harvestable in the spring. In the spring of 2009, corn stover was harvested at 2 sites, each subdivided into 2 parcels. The first parcel was cut and raked in the fall of 2008 (fall parcel), while the second parcel was cut and raked in spring 2009. Fibre from both parcels was baled in the spring 2009. At the first site, a large square baler was used in late April to produce bales measuring 0.8 m x 0.9 m x 1.8 m. On the second site a round baler was used in late May to produce bales of 1.2 m in width by 1.45 m in diameter. On the second site, a small square baler was also used to produce bales of 0.35 m x 0.45 m x 0.60 m (spring cutting only). With the large square baler, an average of 3.9 t DM/ha was harvested equally on the fall parcel and the spring parcel, representing a 48 per cent recovery of biomass based on stover yields.

  7. Nyala and Bushbuck II: A Harvesting Model.

    Science.gov (United States)

    Fay, Temple H.; Greeff, Johanna C.

    1999-01-01

    Adds a cropping or harvesting term to the animal overpopulation model developed in Part I of this article. Investigates various harvesting strategies that might suggest a solution to the overpopulation problem without actually culling any animals. (ASK)

  8. Electrodynamic energy harvester for electrical transformer's ...

    Indian Academy of Sciences (India)

    Electrical transformer; electrodynamic; energy harvester; self-powered ...... Kennedy S P and Gordner T 2013 Hot spot studies for sheet wound transformer wind- ... and Lambert F 2011 Powering low-cost utility sensors using energy harvesting.

  9. Performance Limits of Communication with Energy Harvesting

    KAUST Repository

    Znaidi, Mohamed Ridha

    2016-01-01

    In energy harvesting communications, the transmitters have to adapt transmission to the availability of energy harvested during communication. The performance of the transmission depends on the channel conditions which vary randomly due to mobility

  10. Electronically droplet energy harvesting using piezoelectric cantilevers

    KAUST Repository

    Al Ahmad, Mahmoud Al; Jabbour, Ghassan E.

    2012-01-01

    A report is presented on free falling droplet energy harvesting using piezoelectric cantilevers. The harvester incorporates a multimorph clamped-free cantilever which is composed of five layers of lead zirconate titanate piezoelectric thick films

  11. Derriçadora portátil na colheita total e seletiva de frutos do cafeeiro Portable harvester in the total and selective harvesting of coffee fruits

    Directory of Open Access Journals (Sweden)

    Cristiano Márcio Alves de Souza

    2006-11-01

    Full Text Available O objetivo deste trabalho foi avaliar o desempenho de derriçadoras portáteis durante a colheita seletiva e total dos frutos, em dois sistemas de colheita. Foram determinados a carga pendente da planta, a capacidade de derriça, o índice de desfolha, a eficiência de derriça, o índice de frutos verdes no produto, o nível de ruído e o consumo horário e específico de combustível. O sistema de colheita, utilizando-se duas derriçadoras portáteis, simultaneamente na mesma fileira de cafeeiros, apresentou melhor desempenho. A colheita seletiva foi muito influenciada pela porcentagem de frutos maduros e carga pendente do cafeeiro.The objective of this work was to evaluate the performance of a portable coffee harvester to mountain areas. Two procedures were tested: harvesting all fruits in only one operation, and the selective harvesting. Coffee yield, harvesting capacity, index of leaves taken during harvesting process, harvesting efficiency, noise level and fuel consumption were measured. The harvesting system with two portable harvester presented better performance than with only one machine. Selective harvesting was highly influenced by the percentage of ripen fruits and by coffee yield.

  12. Energy harvesting devices for harvesting energy from terahertz electromagnetic radiation

    Science.gov (United States)

    Novack, Steven D.; Kotter, Dale K.; Pinhero, Patrick J.

    2012-10-09

    Methods, devices and systems for harvesting energy from electromagnetic radiation are provided including harvesting energy from electromagnetic radiation. In one embodiment, a device includes a substrate and one or more resonance elements disposed in or on the substrate. The resonance elements are configured to have a resonant frequency, for example, in at least one of the infrared, near-infrared and visible light spectra. A layer of conductive material may be disposed over a portion of the substrate to form a ground plane. An optical resonance gap or stand-off layer may be formed between the resonance elements and the ground plane. The optical resonance gap extends a distance between the resonance elements and the layer of conductive material approximately one-quarter wavelength of a wavelength of the at least one resonance element's resonant frequency. At least one energy transfer element may be associated with the at least one resonance element.

  13. Waste energy harvesting mechanical and thermal energies

    CERN Document Server

    Ling Bing, Kong; Hng, Huey Hoon; Boey, Freddy; Zhang, Tianshu

    2014-01-01

    Waste Energy Harvesting overviews the latest progress in waste energy harvesting technologies, with specific focusing on waste thermal mechanical energies. Thermal energy harvesting technologies include thermoelectric effect, storage through phase change materials and pyroelectric effect. Waste mechanical energy harvesting technologies include piezoelectric (ferroelectric) effect with ferroelectric materials and nanogenerators. The book aims to strengthen the syllabus in energy, materials and physics and is well suitable for students and professionals in the fields.

  14. Automated visual fruit detection for harvest estimation and robotic harvesting

    OpenAIRE

    Puttemans, Steven; Vanbrabant, Yasmin; Tits, Laurent; Goedemé, Toon

    2016-01-01

    Fully automated detection and localisation of fruit in orchards is a key component in creating automated robotic harvesting systems, a dream of many farmers around the world to cope with large production and personnel costs. In recent years a lot of research on this topic has been performed, using basic computer vision techniques, like colour based segmentation, as a suggested solution. When not using standard RGB cameras, research tends to resort to other sensors, like hyper spectral or 3D. ...

  15. Harvesting systems for the northern forest hardwoods

    Science.gov (United States)

    Chris B. LeDoux

    2011-01-01

    This monograph is a summary of research results and environmental compliance measures for timber harvesting operations. Data are presented from the Northern Research Station's forest inventory and analysis of 20 states in the northern forest hardwoods. Harvesting systems available in the region today are summarized. Equations for estimating harvesting costs are...

  16. Approaches to automated protein crystal harvesting

    Energy Technology Data Exchange (ETDEWEB)

    Deller, Marc C., E-mail: mdeller@scripps.edu; Rupp, Bernhard, E-mail: mdeller@scripps.edu

    2014-01-28

    Approaches to automated and robot-assisted harvesting of protein crystals are critically reviewed. While no true turn-key solutions for automation of protein crystal harvesting are currently available, systems incorporating advanced robotics and micro-electromechanical systems represent exciting developments with the potential to revolutionize the way in which protein crystals are harvested.

  17. A knee-mounted biomechanical energy harvester with enhanced efficiency and safety

    Science.gov (United States)

    Chen, Chao; Chau, Li Yin; Liao, Wei-Hsin

    2017-06-01

    Energy harvesting is becoming a major limiting issue for many portable devices. When undertaking any activity, the human body generates a significant amount of biomechanical energy, which can be collected by means of a portable energy harvester. This energy provides a method of powering portable devices such as prosthetic limbs. In this paper, a knee-mounted energy harvester with enhanced efficiency and safety is proposed and developed to convert mechanical energy into electricity during human motion. This device can change the bi-directional knee input into uni-directional rotation for an electromagnetic generator using a specially designed transmission system. Without the constraint of induced impact on the human body, this device can harvest biomechanical energy from both knee flexion and extension, improving the harvesting efficiency over previous single-direction energy harvesters. It can also provide protection from device malfunction, and increase the safety of current biomechanical energy harvesters. A highly compact and light prototype is developed taking into account human kinematics. The biomechanical energy harvesting system is also modeled and analyzed. The prototype is tested under different conditions including walking, running and climbing stairs, to evaluate the energy harvesting performance and effect on the human gait. The experimental results show that the prototype can harvest an average power of 3.6 W at 1.5 m s-1 walking speed, which is promising for portable electronic devices.

  18. Influence of harvest time on the composition and quality of Rosinjola cultivar virgin olive oils

    Directory of Open Access Journals (Sweden)

    Olivera Koprivnjak

    2012-01-01

    Full Text Available The aim of this investigation was to determine the influence of Rosinjola cultivar fruits harvest time on oil content in olive pastes and on composition and quality of obtained oils. In the late harvest time the higher value of oil in the dry matter of olive paste was determined than in the early harvest time, but the late harvest negatively affected oil quality parameters. The proportion of oleic acid decreased slightly in the late harvest time and linoleic acid increased. The ratio of oleic/linoleic acid, total phenols and ortho-diphenols, as well as bitterness index and antioxidant capacity decreased in the oil obtained from black fruit. Late harvest time influenced the decrease in chlorophyll and carotenoid content and color parameter values (a*, b* and C in obtained oils, but lightness (L* increased. The concentration of volatiles responsible for positive odour of Rosinjola oils decreased, except for aldehydes which increased slightly. Sensory score of oil obtained from the late harvest time decreased, as well as intensities of sensory characteristics olive fruity, apple, green grass, bitter and pungent, while the intensities of characteristics sweet and ripe fruits increased. Oils obtained in the early harvest time were described as harmonious and astringent with pronounced green odour notes, and oils obtained in the late harvest time as overripe and without freshness. The obtained results are important for optimal harvest time determination and understanding the potential of Rosinjola cultivar for production of high quality virgin olive oil with targeted and specific characteristics.

  19. Population Modeling Approach to Optimize Crop Harvest Strategy. The Case of Field Tomato.

    Science.gov (United States)

    Tran, Dinh T; Hertog, Maarten L A T M; Tran, Thi L H; Quyen, Nguyen T; Van de Poel, Bram; Mata, Clara I; Nicolaï, Bart M

    2017-01-01

    In this study, the aim is to develop a population model based approach to optimize fruit harvesting strategies with regard to fruit quality and its derived economic value. This approach was applied to the case of tomato fruit harvesting under Vietnamese conditions. Fruit growth and development of tomato (cv. "Savior") was monitored in terms of fruit size and color during both the Vietnamese winter and summer growing seasons. A kinetic tomato fruit growth model was applied to quantify biological fruit-to-fruit variation in terms of their physiological maturation. This model was successfully calibrated. Finally, the model was extended to translate the fruit-to-fruit variation at harvest into the economic value of the harvested crop. It can be concluded that a model based approach to the optimization of harvest date and harvest frequency with regard to economic value of the crop as such is feasible. This approach allows growers to optimize their harvesting strategy by harvesting the crop at more uniform maturity stages meeting the stringent retail demands for homogeneous high quality product. The total farm profit would still depend on the impact a change in harvesting strategy might have on related expenditures. This model based harvest optimisation approach can be easily transferred to other fruit and vegetable crops improving homogeneity of the postharvest product streams.

  20. Toward a semi-mechanical harvesting platform system for harvesting blueberries with fresh-market quality

    Science.gov (United States)

    Major concerns related to harvesting blueberries for fresh market with over-the-row (OTR) harvesters are that the quality of the fruit harvested with OTR machines is generally low and ground loss is excessive. Machine-harvested blueberries have more internal bruise and usually soften rapidly in col...

  1. Comparison of wood harvesting methods in the Republic of Karelia

    Energy Technology Data Exchange (ETDEWEB)

    Syunev, V.; Sokolov, A.; Konovalov, A.; Katarov, V.; Seliverstov, A.; Gerasimov, Y.; Karvinen, S. email: sari.karvinen@metla.fi; Vaelkky, E.

    2009-07-01

    Impacts of cut-to-length, tree-length and full-tree harvesting technology on direct operating costs, productivity, forest environment, ergonomics and work safety, as well as on wood quality were studied in 2007 and 2008 in 15 harvesting companies in the Republic of Karelia, Russia. Productivity varied within a relatively wide range from 20 to 150 m3 per shift. Fully mechanized full-tree harvesting provided the maximum productivity. The professional skills and experience of harvesting machine operators had a significant impact on the productivity. Direct operating costs had insignificant differences - the average costs were 250 RUB/m3. In the traditional Russian tree-length and full-tree harvesting, real harvesting costs were higher than in the cut-to-length technology, due to additional work at the central processing yard. All the technologies demonstrated an almost identical impact on the lower layers of soil, when applied on sandy or sandy loam soils. Porosity was reduced by 9-10%. On clay loams, the tree-length technology resulted in significant topsoil compaction but, at the same time, formed almost no track. The studied full-tree technology was only acceptable in harvesting sites where no undergrowth preservation was required. Partially mechanized cut-to-length technology ensured high undergrowth preservation. In thinnings the tree-length and the fully mechanized cut-to-length technology resulted in less damage to the remaining trees compared to the other technologies. The best working conditions in terms of ergonomics and occupational safety were provided by the chain consisting of a harvester and a forwarder. It was closely followed by the chain 'feller buncher and wheeled skidder'. Traditional tree-length harvesting with cable skidders demonstrated the worst results in terms of ergonomics, work severity and occupational safety. Fully mechanized cut-to-length technology provided with the best results in the preservation of wood quality The quality

  2. An Inductorless Self-Controlled Rectifier for Piezoelectric Energy Harvesting.

    Science.gov (United States)

    Lu, Shaohua; Boussaid, Farid

    2015-11-19

    This paper presents a high-efficiency inductorless self-controlled rectifier for piezoelectric energy harvesting. High efficiency is achieved by discharging the piezoelectric device (PD) capacitance each time the current produced by the PD changes polarity. This is achieved automatically without the use of delay lines, thereby making the proposed circuit compatible with any type of PD. In addition, the proposed rectifier alleviates the need for an inductor, making it suitable for on-chip integration. Reported experimental results show that the proposed rectifier can harvest up to 3.9 times more energy than a full wave bridge rectifier.

  3. An Inductorless Self-Controlled Rectifier for Piezoelectric Energy Harvesting

    Directory of Open Access Journals (Sweden)

    Shaohua Lu

    2015-11-01

    Full Text Available This paper presents a high-efficiency inductorless self-controlled rectifier for piezoelectric energy harvesting. High efficiency is achieved by discharging the piezoelectric device (PD capacitance each time the current produced by the PD changes polarity. This is achieved automatically without the use of delay lines, thereby making the proposed circuit compatible with any type of PD. In addition, the proposed rectifier alleviates the need for an inductor, making it suitable for on-chip integration. Reported experimental results show that the proposed rectifier can harvest up to 3.9 times more energy than a full wave bridge rectifier.

  4. Effects of harvesting on spatial and temporal diversity of carbon stocks in a boreal forest landscape.

    Science.gov (United States)

    Ter-Mikaelian, Michael T; Colombo, Stephen J; Chen, Jiaxin

    2013-10-01

    Carbon stocks in managed forests of Ontario, Canada, and in harvested wood products originated from these forests were estimated for 2010-2100. Simulations included four future forest harvesting scenarios based on historical harvesting levels (low, average, high, and maximum available) and a no-harvest scenario. In four harvesting scenarios, forest carbon stocks in Ontario's managed forest were estimated to range from 6202 to 6227 Mt C (millions of tons of carbon) in 2010, and from 6121 to 6428 Mt C by 2100. Inclusion of carbon stored in harvested wood products in use and in landfills changed the projected range in 2100 to 6710-6742 Mt C. For the no-harvest scenario, forest carbon stocks were projected to change from 6246 Mt C in 2010 to 6680 Mt C in 2100. Spatial variation in projected forest carbon stocks was strongly related to changes in forest age (r = 0.603), but had weak correlation with harvesting rates. For all managed forests in Ontario combined, projected carbon stocks in combined forest and harvested wood products converged to within 2% difference by 2100. The results suggest that harvesting in the boreal forest, if applied within limits of sustainable forest management, will eventually have a relatively small effect on long-term combined forest and wood products carbon stocks. However, there was a large time lag to approach carbon equality, with more than 90 years with a net reduction in stored carbon in harvested forests plus wood products compared to nonharvested boreal forest which also has low rates of natural disturbance. The eventual near equivalency of carbon stocks in nonharvested forest and forest that is harvested and protected from natural disturbance reflects both the accumulation of carbon in harvested wood products and the relatively young age at which boreal forest stands undergo natural succession in the absence of disturbance.

  5. Harvesting NASA's Common Metadata Repository

    Science.gov (United States)

    Shum, D.; Mitchell, A. E.; Durbin, C.; Norton, J.

    2017-12-01

    As part of NASA's Earth Observing System Data and Information System (EOSDIS), the Common Metadata Repository (CMR) stores metadata for over 30,000 datasets from both NASA and international providers along with over 300M granules. This metadata enables sub-second discovery and facilitates data access. While the CMR offers a robust temporal, spatial and keyword search functionality to the general public and international community, it is sometimes more desirable for international partners to harvest the CMR metadata and merge the CMR metadata into a partner's existing metadata repository. This poster will focus on best practices to follow when harvesting CMR metadata to ensure that any changes made to the CMR can also be updated in a partner's own repository. Additionally, since each partner has distinct metadata formats they are able to consume, the best practices will also include guidance on retrieving the metadata in the desired metadata format using CMR's Unified Metadata Model translation software.

  6. Forage Harvest and Transport Costs

    Energy Technology Data Exchange (ETDEWEB)

    Butler, J.; Downing, M.; Turhollow, A.

    1998-12-01

    An engineering-economic approach is used to calculate harvest, in-field transport, and over-the-road transport costs for hay as bales and modules, silage, and crop residues as bales and modules. Costs included are equipment depreciation interest; fuel, lube, and oil; repairs; insurance, housing, and taxes; and labor. Field preparation, pest control, fertilizer, land, and overhead are excluded from the costs calculated Equipment is constrained by power available, throughput or carrying capacity, and field speed.

  7. Energy-harvesting shock absorber with a mechanical motion rectifier

    Science.gov (United States)

    Li, Zhongjie; Zuo, Lei; Kuang, Jian; Luhrs, George

    2013-02-01

    Energy-harvesting shock absorbers are able to recover the energy otherwise dissipated in the suspension vibration while simultaneously suppressing the vibration induced by road roughness. They can work as a controllable damper as well as an energy generator. An innovative design of regenerative shock absorbers is proposed in this paper, with the advantage of significantly improving the energy harvesting efficiency and reducing the impact forces caused by oscillation. The key component is a unique motion mechanism, which we called ‘mechanical motion rectifier (MMR)’, to convert the oscillatory vibration into unidirectional rotation of the generator. An implementation of a MMR-based harvester with high compactness is introduced and prototyped. A dynamic model is created to analyze the general properties of the motion rectifier by making an analogy between mechanical systems and electrical circuits. The model is capable of analyzing electrical and mechanical components at the same time. Both simulation and experiments are carried out to verify the modeling and the advantages. The prototype achieved over 60% efficiency at high frequency, much better than conventional regenerative shock absorbers in oscillatory motion. Furthermore, road tests are done to demonstrate the feasibility of the MMR shock absorber, in which more than 15 Watts of electricity is harvested while driving at 15 mph on a smooth paved road. The MMR-based design can also be used for other applications of vibration energy harvesting, such as from tall buildings or long bridges.

  8. Energy-harvesting shock absorber with a mechanical motion rectifier

    International Nuclear Information System (INIS)

    Li, Zhongjie; Zuo, Lei; Kuang, Jian; Luhrs, George

    2013-01-01

    Energy-harvesting shock absorbers are able to recover the energy otherwise dissipated in the suspension vibration while simultaneously suppressing the vibration induced by road roughness. They can work as a controllable damper as well as an energy generator. An innovative design of regenerative shock absorbers is proposed in this paper, with the advantage of significantly improving the energy harvesting efficiency and reducing the impact forces caused by oscillation. The key component is a unique motion mechanism, which we called ‘mechanical motion rectifier (MMR)’, to convert the oscillatory vibration into unidirectional rotation of the generator. An implementation of a MMR-based harvester with high compactness is introduced and prototyped. A dynamic model is created to analyze the general properties of the motion rectifier by making an analogy between mechanical systems and electrical circuits. The model is capable of analyzing electrical and mechanical components at the same time. Both simulation and experiments are carried out to verify the modeling and the advantages. The prototype achieved over 60% efficiency at high frequency, much better than conventional regenerative shock absorbers in oscillatory motion. Furthermore, road tests are done to demonstrate the feasibility of the MMR shock absorber, in which more than 15 Watts of electricity is harvested while driving at 15 mph on a smooth paved road. The MMR-based design can also be used for other applications of vibration energy harvesting, such as from tall buildings or long bridges. (paper)

  9. Wideband quin-stable energy harvesting via combined nonlinearity

    Directory of Open Access Journals (Sweden)

    Chen Wang

    2017-04-01

    Full Text Available In this work, we propose a wideband quintuple-well potential piezoelectric-based vibration energy harvester using a combined nonlinearity: the magnetic nonlinearity induced by magnetic force and the piecewise-linearity produced by mechanical impact. With extra stable states compared to other multi-stable harvesters, the quin-stable harvester can distribute its potential energy more uniformly, which provides shallower potential wells and results in lower excitation threshold for interwell motion. The mathematical model of this quin-stable harvester is derived and its equivalent piecewise-nonlinear restoring force is measured in the experiment and identified as piecewise polynomials. Numerical simulations and experimental verifications are performed in different levels of sinusoid excitation ranging from 1 to 25 Hz. The results demonstrate that, with lower potential barriers compared with tri-stable counterpart, the quin-stable arrangement can escape potential wells more easily for doing high-energy interwell motion over a wider band of frequencies. Moreover, by utilizing the mechanical stoppers, this harvester can produce significant output voltage under small tip deflections, which results in a high power density and is especially suitable for a compact MEMS approach.

  10. Review of magnetostrictive vibration energy harvesters

    Science.gov (United States)

    Deng, Zhangxian; Dapino, Marcelo J.

    2017-10-01

    The field of energy harvesting has grown concurrently with the rapid development of portable and wireless electronics in which reliable and long-lasting power sources are required. Electrochemical batteries have a limited lifespan and require periodic recharging. In contrast, vibration energy harvesters can supply uninterrupted power by scavenging useful electrical energy from ambient structural vibrations. This article reviews the current state of vibration energy harvesters based on magnetostrictive materials, especially Terfenol-D and Galfenol. Existing magnetostrictive harvester designs are compared in terms of various performance metrics. Advanced techniques that can reduce device size and improve performance are presented. Models for magnetostrictive devices are summarized to guide future harvester designs.

  11. Sustainable harvest of waterbirds: a global review

    DEFF Research Database (Denmark)

    Kanstrup, Niels

    ABSTRACT Waterbirds have a long tradition of being harvested in various ways. In many countries, the harvest takes place as a primary food source, but recreational hunting is also very popular. Various methods are used. Subsistence hunting of waterbirds has a history that dates back to the dawn...... and the degree of stability in local communities obtained through nature conservation. In many countries there is a long tradition of detailed wildlife harvest management including programmes for bag surveys and monitoring of harvest levels. In most countries, however, the management of waterbird harvests...

  12. Charge-state distribution measurements of ^{238}U and ^{136}Xe at 11  MeV/nucleon using gas charge stripper

    Directory of Open Access Journals (Sweden)

    H. Kuboki

    2010-09-01

    Full Text Available The charge-state distributions and equilibrium charge states of uranium (^{238}U and xenon (^{136}Xe ions at 11  MeV/nucleon were determined using a gas charge stripper. A differential pumping system facilitated the increase of the nitrogen gas thickness up to 1.3  mg/cm^{2}, which is sufficient for the most probable charge state to attain equilibrium. The charge states of ^{238}U attain equilibrium at 56.0, 56.6, and 55.7 in N_{2}, Ar, and CO_{2} media with thicknesses of 125, 79, and 126  μg/cm^{2}, respectively, while those of ^{136}Xe attain equilibrium at 40.5, 40.1, and 40.3 in N_{2}, Ar, and CO_{2} media with thicknesses of 163, 95, and 139  μg/cm^{2}, respectively. The equilibrium charge states of ^{136}Xe are acceptable for acceleration by the subsequent cyclotron. The measured data of ^{238}U were used to devise an empirical formula for the prediction of the equilibrium charge state in gaseous media over the energy region of 0.01–60  MeV/nucleon. The equilibrium charge state of ^{136}Xe as predicted by the devised formula is in good agreement with the data.

  13. A high charge state heavy ion beam source for heavy ion fusion

    International Nuclear Information System (INIS)

    Eylon, S.; Henestroza, E.

    1996-01-01

    A high current, low emittance, high charge state heavy ion beam source is being developed. This is designed to deliver a heavy ion fusion (HIF) driver accelerator scale beam. Using a high charge state beam in a driver accelerator for HIF may increase the acceleration efficiency, leading to a reduction in the driver accelerator size and cost. The proposed source system, which consists of a gas beam electron stripper followed by a high charge state beam separator, can be added to existing single charge state, low emittance, high brightness ion sources and injectors. We shall report on the source physics design using 3D beam simulations and experimental feasibility study results using a neutral gas stripper and a beam separator at the exit of the LBL 2 MV injector. (orig.)

  14. Issues in vibration energy harvesting

    Science.gov (United States)

    Zhang, Hui; Corr, Lawrence R.; Ma, Tianwei

    2018-05-01

    In this study, fundamental issues related to bandwidth and nonlinear resonance in vibrational energy harvesting devices are investigated. The results show that using bandwidth as a criterion to measure device performance can be misleading. For a linear device, an enlarged bandwidth is achieved at the cost of sacrificing device performance near resonance, and thus widening the bandwidth may offer benefits only when the natural frequency of the linear device cannot match the dominant excitation frequency. For a nonlinear device, since the principle of superposition does not apply, the ''broadband" performance improvements achieved for single-frequency excitations may not be achievable for multi-frequency excitations. It is also shown that a large-amplitude response based on the traditional ''nonlinear resonance" does not always result in the optimal performance for a nonlinear device because of the negative work done by the excitation, which indicates energy is returned back to the excitation. Such undesired negative work is eliminated at global resonance, a generalized resonant condition for both linear and nonlinear systems. While the linear resonance is a special case of global resonance for a single-frequency excitation, the maximum potential of nonlinear energy harvesting can be reached for multi-frequency excitations by using global resonance to simultaneously harvest energy distributed over multiple frequencies.

  15. Harvesting Information from Heterogeneous Sources

    DEFF Research Database (Denmark)

    Qureshi, Pir Abdul Rasool; Memon, Nasrullah; Wiil, Uffe Kock

    2011-01-01

    The abundance of information regarding any topic makes the Internet a very good resource. Even though searching the Internet is very easy, what remains difficult is to automate the process of information extraction from the available online information due to the lack of structure and the diversi...... with performance of our tool with respect to each format. Finally, the different potential applications of the proposed tool are discussed with special emphasis on open source intelligence....... in the sharing methods. Most of the times, information is stored in different proprietary formats, complying with different standards and protocols which makes tasks like data mining and information harvesting very difficult. In this paper, an information harvesting tool (heteroHarvest) is presented...... with objectives to address these problems by filtering the useful information and then normalizing the information in a singular non hypertext format. We also discuss state of the art tools along with the shortcomings and present the results of an analysis carried out over different heterogeneous formats along...

  16. Ultra high vacuum activities and required modification at 14 UD BARC-TIFR pelletron accelerator facility

    International Nuclear Information System (INIS)

    Sharma, S.C.; Ninawe, N.G.; Ramjilal; Bhagwat, P.V.; Salvi, S.B.

    2003-01-01

    Full text: The 14 UD pelletron accelerator is working round the clock since 1989. The accelerator is housed inside a tank which is 6 meter in diameter and 25 meter long. The accelerator tank is pressurized with SF 6 at 80 to 100 PSIG in order to achieve 14MV. In pelletron, ions are extracted from SNICS are pre-accelerated up to 300 keV before being injected into low energy accelerator tube. In the terminal which is at high potential (4MV to 14 MV), the ion beam pass through the stripper and positive ions with high charge states are produced. The high energy beams are focussed and analyzed by 90 deg magnet. The analyzed beam is then transported to the various experimental ports. In order to achieve uniform ultra high vacuum (to reduce the loss of intensity and spread in the energy of ions beams) in more than 100 metre and 100 mm diameter beam lines including magnet chambers and various beam diagnostic devices, combination of getter-ion pumps and turbo pumps are being used at Pelletron Accelerator Facility. The 14 UD pelletron is equipped with a combination of foil and gas stripper in high voltage terminal section. The foil and gas stripper in the terminal section are mainly used for stripping of light and heavy ions respectively. The gas stripper plays a great role for stripping of heavy ions and its efficiency depends on gas stripper parameters and supporting pumps. The gas stripper is originally installed with getter pumps. These pumps required periodic replacement of titanium cartridges and slowly the pumping speed used to diminish with time. A new recirculation turbo molecular pumps based system is being designed to improve good beam transmission. Details of design will be presented. Proton beam of tens of MeV energy and μA range current is in demand to carry out specific radiochemistry experiments in this facility. It is proposed to built and accommodate a proton experimental setup in the tower area of the existing facility. Details of required UHV system for

  17. Bistable energy harvesting enhancement with an auxiliary linear oscillator

    Science.gov (United States)

    Harne, R. L.; Thota, M.; Wang, K. W.

    2013-12-01

    Recent work has indicated that linear vibrational energy harvesters with an appended degree-of-freedom (DOF) may be advantageous for introducing new dynamic forms to extend the operational bandwidth. Given the additional interest in bistable harvester designs, which exhibit a propitious snap through effect from one stable state to the other, it is a logical extension to explore the influence of an added DOF to a bistable system. However, bistable snap through is not a resonant phenomenon, which tempers the presumption that the dynamics induced by an additional DOF on bistable designs would inherently be beneficial as for linear systems. This paper presents two analytical formulations to assess the fundamental and superharmonic steady-state dynamics of an excited bistable energy harvester to which is attached an auxiliary linear oscillator. From an energy harvesting perspective, the model predicts that the additional linear DOF uniformly amplifies the bistable harvester response magnitude and generated power for excitation frequencies less than the attachment’s resonance while improved power density spans a bandwidth below this frequency. Analyses predict bandwidths having co-existent responses composed of a unique proportion of fundamental and superharmonic dynamics. Experiments validate key analytical predictions and observe the ability for the coupled system to develop an advantageous multi-harmonic interwell response when the initial conditions are insufficient for continuous high-energy orbit at the excitation frequency. Overall, the addition of an auxiliary linear oscillator to a bistable harvester is found to be an effective means of enhancing the energy harvesting performance and robustness.

  18. Economic valuation of subsistence harvest of wildlife in Madagascar.

    Science.gov (United States)

    Golden, Christopher D; Bonds, Matthew H; Brashares, Justin S; Rasolofoniaina, B J Rodolph; Kremen, Claire

    2014-02-01

    Wildlife consumption can be viewed as an ecosystem provisioning service (the production of a material good through ecological functioning) because of wildlife's ability to persist under sustainable levels of harvest. We used the case of wildlife harvest and consumption in northeastern Madagascar to identify the distribution of these services to local households and communities to further our understanding of local reliance on natural resources. We inferred these benefits from demand curves built with data on wildlife sales transactions. On average, the value of wildlife provisioning represented 57% of annual household cash income in local communities from the Makira Natural Park and Masoala National Park, and harvested areas produced an economic return of U.S.$0.42 ha(-1) · year(-1). Variability in value of harvested wildlife was high among communities and households with an approximate 2 orders of magnitude difference in the proportional value of wildlife to household income. The imputed price of harvested wildlife and its consumption were strongly associated (p< 0.001), and increases in price led to reduced harvest for consumption. Heightened monitoring and enforcement of hunting could increase the costs of harvesting and thus elevate the price and reduce consumption of wildlife. Increased enforcement would therefore be beneficial to biodiversity conservation but could limit local people's food supply. Specifically, our results provide an estimate of the cost of offsetting economic losses to local populations from the enforcement of conservation policies. By explicitly estimating the welfare effects of consumed wildlife, our results may inform targeted interventions by public health and development specialists as they allocate sparse funds to support regions, households, or individuals most vulnerable to changes in access to wildlife. © 2013 Society for Conservation Biology.

  19. Harvested wood products and REDD+: looking beyond the forest border

    Directory of Open Access Journals (Sweden)

    Tunggul Butarbutar

    2016-05-01

    Full Text Available Abstract Background The focus of REDD+ is sensu stricto on maintaining forest carbon stocks. We extend the scope of sustainable management of forest from forests to timber utilization, and study carbon offsets resulting from the utilization of harvested timber for bio energy or harvested wood products (HWPs. The emission budget of harvesting operations depends on the loss of standing biomass by timber extracted from the forest site and logging losses on the one side, and on the other on the wood end use and the utilization of processing residues. We develop two scenarios to quantify the magnitude of CO2 emissions by (1 energetic utilization, and (2 energetic and material utilization of harvested timber and compare the substitution effects for different fossil energy sources. Results The direct energetic use of harvested timber does not compensate for the losses of forest carbon stock. Logging residuals and displacement factors reflecting different wood use constitute by far the most important factor in potential emission reductions. Substitution effects resulting from energetic use of mill residuals and from HWPs have only a subordinated contribution to the total emissions as well as the type of fossil fuel utilized to quantify substitution effects. Material substitution effects associated with harvested wood products show a high potential to increase the climate change benefits. Conclusions The observation and perception of REDD+ should not be restricted to sustainable management and reduced impact logging practices in the forest domain but should be extended to the utilization of extracted timber. Substitution effects from material and energetic utilization of harvested timber result in considerable emission reductions, which can compensate for the loss of forest carbon, and eventually contribute to the overall climate change mitigation benefits from forestry sector.

  20. Autotransplantation donor tooth site harvesting using piezosurgery.

    Science.gov (United States)

    Ylikontiola, Leena P; Sándor, George K

    2016-01-01

    The harvesting of a tooth as a candidate for tooth autotransplantation requires that the delicate dental tissues around the tooth be minimally traumatized. This is especially so for the periradicular tissues of the tooth root and the follicular tissues surrounding the crown. The aim of this report is to describe the use of piezosurgery as an attempt at morbidity reduction in the harvesting of teeth for autotransplantation. A piezosurgical handpiece and its selection of tips were easily adapted to allow the harvesting and delivery of teeth for autotransplantation purposes. Twenty premolar teeth were harvested using a piezosurgical device. The harvested teeth were subsequently successfully autotransplanted. All twenty teeth healed in a satisfactory manner without excessive mobility or ankyloses. Piezosurgery avoids some of the traumatic aspects of harvesting teeth and removing bone which are associated with thermal damage from the use of conventional rotary instruments or saws. Piezosurgery can be adapted to facilitate the predictable harvesting of teeth for autotransplantation purposes.

  1. Energy Requirements for Biomass Harvest and Densification

    Directory of Open Access Journals (Sweden)

    Kevin Shinners

    2018-03-01

    Full Text Available This research quantified the unit and bulk density of several biomass crops across a variety of harvest and processing methods, as well as the energy and fuel requirements for these operations. A load density of approximately 240 kg·m−3 is needed to reach the legal weight limit of most transporters. Of the three types of balers studied, only the high density (HD large square baler achieved this target density. However, the specific energy and fuel requirements increased exponentially with bale density, and at the maximum densities for corn stover and switchgrass, the dry basis energy and fuel requirements ranged from 4.0 to 5.0 kW·h·Mg−1 and 1.2 to 1.4 L·Mg−1, respectively. Throughputs of tub grinders when grinding bales was less than any other harvesting or processing methods investigated, so specific energy and fuel requirements were high and ranged from 13 to 32 kW·h·Mg−1 and 5.0 to 11.3 L·Mg−1, respectively. Gross size-reduction by pre-cutting at baling increased bale density by less than 6% and increased baling energy requirements by 11% to 22%, but pre-cut bales increased the tub grinder throughput by 25% to 45% and reduced specific fuel consumption for grinding by 20% to 53%. Given the improvement in tub grinder operation, pre-cutting bales should be considered as a means to increase grinder throughput. Additional research is needed to determine the energy required to grind high density pre-cut bales at high throughputs so that better estimates of total energy required for a high density bale system can be made. An alternative bulk feedstock system was investigated that involved chopping moist biomass crops with a precision-cut forage harvester, compacting the bulk material in a silo bag, and then segmenting the densified material into modules optimized for efficient transport. The specific fuel use for chopping and then compacting biomass crops in the silo bag ranged from 1.6 to 3.0 L·Mg−1 and 0.5 to 1.3 L·Mg−1

  2. N -annulated perylene as an efficient electron donor for porphyrin-based dyes: Enhanced light-harvesting ability and high-efficiency Co(II/III)-based dye-sensitized solar cells

    KAUST Repository

    Luo, Jie

    2014-01-08

    Porphyrin-based dyes recently have become good candidates for dye-sensitized solar cells (DSCs). However, the bottleneck is how to further improve their light-harvesting ability. In this work, N-annulated perylene (NP) was used to functionalize the Zn-porphyrin, and four "push-pull"-type NP-substituted and fused porphyrin dyes with intense absorption in the visible and even in the near-infrared (NIR) region were synthesized. Co(II/III)-based DSC device characterizations revealed that dyes WW-5 and WW-6, in which an ethynylene spacer is incorporated between the NP and porphyrin core, showed pantochromatic photon-to-current conversion efficiency action spectra in the visible and NIR region, with a further red-shift of about 90 and 60 nm, respectively, compared to the benchmark molecule YD2-o-C8. As a result, the short-circuit current density was largely increased, and the devices displayed power conversion efficiencies as high as 10.3% and 10.5%, respectively, which is comparable to that of the YD2-o-C8 cell (η = 10.5%) under the same conditions. On the other hand, the dye WW-3 in which the NP unit is directly attached to the porphyrin core showed a moderate power conversion efficiency (η = 5.6%) due to the inefficient π-conjugation, and the NP-fused dye WW-4 exhibited even poorer performance due to its low-lying LUMO energy level and nondisjointed HOMO/LUMO profile. Our detailed physical measurements (optical and electrochemical), density functional theory calculations, and photovoltaic characterizations disclosed that the energy level alignment, the molecular orbital profile, and dye aggregation all played very important roles on the interface electron transfer and charge recombination kinetics. © 2013 American Chemical Society.

  3. Design optimization of PVDF-based piezoelectric energy harvesters

    Directory of Open Access Journals (Sweden)

    Jundong Song

    2017-09-01

    Full Text Available Energy harvesting is a promising technology that powers the electronic devices via scavenging the ambient energy. Piezoelectric energy harvesters have attracted considerable interest for their high conversion efficiency and easy fabrication in minimized sensors and transducers. To improve the output capability of energy harvesters, properties of piezoelectric materials is an influential factor, but the potential of the material is less likely to be fully exploited without an optimized configuration. In this paper, an optimization strategy for PVDF-based cantilever-type energy harvesters is proposed to achieve the highest output power density with the given frequency and acceleration of the vibration source. It is shown that the maximum power output density only depends on the maximum allowable stress of the beam and the working frequency of the device, and these two factors can be obtained by adjusting the geometry of piezoelectric layers. The strategy is validated by coupled finite-element-circuit simulation and a practical device. The fabricated device within a volume of 13.1 mm3 shows an output power of 112.8 μW which is comparable to that of the best-performing piezoceramic-based energy harvesters within the similar volume reported so far.

  4. Modelling of a bridge-shaped nonlinear piezoelectric energy harvester

    International Nuclear Information System (INIS)

    Gafforelli, G; Corigliano, A; Xu, R; Kim, S G

    2013-01-01

    Piezoelectric MicroElectroMechanical Systems (MEMS) energy harvesting is an attractive technology for harvesting small magnitudes of energy from ambient vibrations. Increasing the operating frequency bandwidth of such devices is one of the major issues for real world applications. A MEMS-scale doubly clamped nonlinear beam resonator is designed and developed to demonstrate very wide bandwidth and high power density. In this paper a first complete theoretical discussion of nonlinear resonating piezoelectric energy harvesting is provided. The sectional behaviour of the beam is studied through the Classical Lamination Theory (CLT) specifically modified to introduce the piezoelectric coupling and nonlinear Green-Lagrange strain tensor. A lumped parameter model is built through Rayleigh-Ritz Method and the resulting nonlinear coupled equations are solved in the frequency domain through the Harmonic Balance Method (HBM). Finally, the influence of external load resistance on the dynamic behaviour is studied. The theoretical model shows that nonlinear resonant harvesters have much wider power bandwidth than that of linear resonators but their maximum power is still bounded by the mechanical damping as is the case for linear resonating harvesters

  5. Power Control Optimization of an Underwater Piezoelectric Energy Harvester

    Directory of Open Access Journals (Sweden)

    Iñigo Aramendia

    2018-03-01

    Full Text Available Over the past few years, it has been established that vibration energy harvesters with intentionally designed components can be used for frequency bandwidth enhancement under excitation for sufficiently high vibration amplitudes. Pipelines are often necessary means of transporting important resources such as water, gas, and oil. A self-powered wireless sensor network could be a sustainable alternative for in-pipe monitoring applications. A new control algorithm has been developed and implemented into an underwater energy harvester. Firstly, a computational study of a piezoelectric energy harvester for underwater applications has been studied for using the kinetic energy of water flow at four different Reynolds numbers Re = 3000, 6000, 9000, and 12,000. The device consists of a piezoelectric beam assembled to an oscillating cylinder inside the water of pipes from 2 to 5 inches in diameter. Therefore, unsteady simulations have been performed to study the dynamic forces under different water speeds. Secondly, a new control law strategy based on the computational results has been developed to extract as much energy as possible from the energy harvester. The results show that the harvester can efficiently extract the power from the kinetic energy of the fluid. The maximum power output is 996.25 µW and corresponds to the case with Re = 12,000.

  6. Characterization of Energy Availability in RF Energy Harvesting Networks

    Directory of Open Access Journals (Sweden)

    Daniela Oliveira

    2016-01-01

    Full Text Available The multiple nodes forming a Radio Frequency (RF Energy Harvesting Network (RF-EHN have the capability of converting received electromagnetic RF signals in energy that can be used to power a network device (the energy harvester. Traditionally the RF signals are provided by high power transmitters (e.g., base stations operating in the neighborhood of the harvesters. Admitting that the transmitters are spatially distributed according to a spatial Poisson process, we start by characterizing the distribution of the RF power received by an energy harvester node. Considering Gamma shadowing and Rayleigh fading, we show that the received RF power can be approximated by the sum of multiple Gamma distributions with different scale and shape parameters. Using the distribution of the received RF power, we derive the probability of a node having enough energy to transmit a packet after a given amount of charging time. The RF power distribution and the probability of a harvester having enough energy to transmit a packet are validated through simulation. The numerical results obtained with the proposed analysis are close to the ones obtained through simulation, which confirms the accuracy of the proposed analysis.

  7. Scalable single point power extraction for compact mobile and stand-alone solar harvesting power sources based on fully printed organic photovoltaic modules and efficient high voltage DC/DC conversion

    DEFF Research Database (Denmark)

    Garcia Valverde, Rafael; Villarejo, José A.; Hösel, Markus

    2015-01-01

    (AM1.5G, 1000 W m−2). As a demonstration we present a scalable fully integrated and compact power unit for mobile applications comprising solar energy harvesting OPV modules, power conversion and storage. Applications possible include electrical charging of mobile devices, illumination using LED lamps...

  8. N -annulated perylene as an efficient electron donor for porphyrin-based dyes: Enhanced light-harvesting ability and high-efficiency Co(II/III)-based dye-sensitized solar cells

    KAUST Repository

    Luo, Jie; Xu, Mingfei; Li, Renzhi; Huang, Kuo-Wei; Jiang, Changyun; Qi, Qingbiao; Zeng, Wangdong; Zhang, Jie; Chi, Chunyan; Wang, Peng; Wu, Jishan

    2014-01-01

    Porphyrin-based dyes recently have become good candidates for dye-sensitized solar cells (DSCs). However, the bottleneck is how to further improve their light-harvesting ability. In this work, N-annulated perylene (NP) was used to functionalize

  9. Optical arc sensor using energy harvesting power source

    Science.gov (United States)

    Choi, Kyoo Nam; Rho, Hee Hyuk

    2016-06-01

    Wireless sensors without external power supply gained considerable attention due to convenience both in installation and operation. Optical arc detecting sensor equipping with self sustaining power supply using energy harvesting method was investigated. Continuous energy harvesting method was attempted using thermoelectric generator to supply standby power in micro ampere scale and operating power in mA scale. Peltier module with heat-sink was used for high efficiency electricity generator. Optical arc detecting sensor with hybrid filter showed insensitivity to fluorescent and incandescent lamps under simulated distribution panel condition. Signal processing using integrating function showed selective arc discharge detection capability to different arc energy levels, with a resolution below 17J energy difference, unaffected by bursting arc waveform. The sensor showed possibility for application to arc discharge detecting sensor in power distribution panel. Also experiment with proposed continuous energy harvesting method using thermoelectric power showed possibility as a self sustainable power source of remote sensor.

  10. Optical arc sensor using energy harvesting power source

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Kyoo Nam, E-mail: knchoi@inu.ac.kr; Rho, Hee Hyuk, E-mail: rdoubleh0902@inu.ac.kr [Dept. of Information and Telecommunication Engineering Incheon National University Incheon 22012 (Korea, Republic of)

    2016-06-03

    Wireless sensors without external power supply gained considerable attention due to convenience both in installation and operation. Optical arc detecting sensor equipping with self sustaining power supply using energy harvesting method was investigated. Continuous energy harvesting method was attempted using thermoelectric generator to supply standby power in micro ampere scale and operating power in mA scale. Peltier module with heat-sink was used for high efficiency electricity generator. Optical arc detecting sensor with hybrid filter showed insensitivity to fluorescent and incandescent lamps under simulated distribution panel condition. Signal processing using integrating function showed selective arc discharge detection capability to different arc energy levels, with a resolution below 17 J energy difference, unaffected by bursting arc waveform. The sensor showed possibility for application to arc discharge detecting sensor in power distribution panel. Also experiment with proposed continuous energy harvesting method using thermoelectric power showed possibility as a self sustainable power source of remote sensor.

  11. Flexible wearable sensor nodes with solar energy harvesting.

    Science.gov (United States)

    Taiyang Wu; Arefin, Md Shamsul; Redoute, Jean-Michel; Yuce, Mehmet Rasit

    2017-07-01

    Wearable sensor nodes have gained a lot of attention during the past few years as they can monitor and record people's physical parameters in real time. Wearable sensor nodes can promote healthy lifestyles and prevent the occurrence of potential illness or injuries. This paper presents a flexible wearable sensor system powered by an efficient solar energy harvesting technique. It can measure the subject's heartbeats using a photoplethysmography (PPG) sensor and perform activity monitoring using an accelerometer. The solar energy harvester adopts an output current based maximum power point tracking (MPPT) algorithm, which controls the solar panel to operate within its high output power range. The power consumption of the flexible sensor nodes has been investigated under different operation conditions. Experimental results demonstrate that wearable sensor nodes can work for more than 12 hours when they are powered by the solar energy harvester for 3 hours in the bright sunlight.

  12. A batch process micromachined thermoelectric energy harvester: fabrication and characterization

    International Nuclear Information System (INIS)

    Su, J; Goedbloed, M; Van Andel, Y; De Nooijer, M C; Elfrink, R; Wang, Z; Vullers, R J M; Leonov, V

    2010-01-01

    Micromachined thermopiles are considered as a cost-effective solution for energy harvesters working at a small temperature difference and weak heat flows typical for, e.g., the human body. They can be used for powering autonomous wireless sensor nodes in a body area network. In this paper, a micromachined thermoelectric energy harvester with 6 µm high polycrystalline silicon germanium (poly-SiGe) thermocouples fabricated on a 6 inch wafer is presented. An open circuit voltage of 1.49 V and an output power of 0.4 µW can be generated with 3.5 K temperature difference in a model of a wearable micromachined energy harvester of the discussed design, which has a die size of 1.0 mm × 2.5 mm inside a watch-size generator

  13. Sustainability of Mangrove Harvesting: How do Harvesters' Perceptions Differ from Ecological Analysis?

    Directory of Open Access Journals (Sweden)

    Laura López-Hoffman

    2006-12-01

    Full Text Available To harvest biological resources sustainably, it is first necessary to understand what "sustainability" means in an ecological context, and what it means to the people who use the resources. As a case study, we examined the extractive logging of the mangrove Rhizophora mangle in the Río Limón area of Lake Maracaibo, in western Venezuela. The ecological definition of sustainable harvesting is harvesting that allows population numbers to be maintained or to increase over time. In interviews, the harvesters defined sustainable harvesting as levels permitting the maintenance of the mangrove population over two human generations, about 50 yr. In Río Limón, harvesters extract a combination of small adult and juvenile trees. Harvesting rates ranged from 7-35% of small adult trees. These harvesting levels would be sustainable according to the harvester's definition as long as juvenile harvesting was less than 40%. However, some harvesting levels that would be sustainable according to the harvesters were ecologically unsustainable, i.e., eventually causing declines in mangrove population numbers. It was also determined that the structure of mangrove forests was significantly affected by harvesting; even areas harvested at low, ecologically sustainable intensities had significantly fewer adult trees than undisturbed sites. Western Venezuela has no organized timber industry, so mangrove logs are used in many types of construction. A lagging economy and a lack of alternative construction materials make mangrove harvesting inevitable, and for local people, an economic necessity. This creates a trade-off between preserving the ecological characteristics of the mangrove population and responding to human needs. In order to resolve this situation, we recommended a limited and adaptive mangrove harvesting regime. We also suggest that harvesters could participate in community-based management programs as harvesting monitors.

  14. Applying New Technologies to Transform Blueberry Harvesting

    Directory of Open Access Journals (Sweden)

    Fumiomi Takeda

    2017-05-01

    Full Text Available The growth of the blueberry industry in the past three decades has been remarkably robust. However, a labor shortage for hand harvesting, increasingly higher labor costs, and low harvest efficiencies are becoming bottlenecks for sustainable development of the fresh market blueberry production. In this study, we evaluated semi-mechanical harvesting systems consisting of a harvest-aid platform with soft fruit catching surfaces that collected the fruit detached by portable, hand-held, pneumatic shakers. The softer fruit catching surfaces were not glued to the hard sub-surfaces of the harvest-aid platform, but suspended over them. Also, the ergonomic aspect of operating powered harvesting equipment was determined. The pneumatic shakers removed 3.5 to 15 times more fruit (g/min than by hand. Soft fruit catching surfaces reduced impact force and bruise damage. Fruit firmness was higher in fruit harvested by hand compared to that by pneumatic shakers in some cultivars. The bruise area was less than 8% in fruit harvested by hand and with semi-mechanical harvesting system. The percentage of blue, packable fruit harvested by pneumatic shakers comprised as much as 90% of the total, but less than that of hand-harvested fruit. The ergonomic analysis by electromyography showed that muscle strain in the back, shoulders, and forearms was low in workers operating the light-weight, pneumatic shakers that were tethered to the platform with a tool balancer. The new harvesting method can reduce the labor requirement to about 100 hour/hectare/year and help to mitigate the rising labor cost and shortage of workers for harvesting fresh-market quality blueberries.

  15. Improving the energy balance of grass-based anaerobic digestion through combined harvesting and pretreatment

    DEFF Research Database (Denmark)

    Tsapekos, Panagiotis; Kougias, Panagiotis; Egelund, H.

    2017-01-01

    on meadow and cultivated grass silages. The results showed that relatively high methane production can be achieved from meadow and cultivated grass harvested in different seasons. The findings indicated that the bioenergy production can be improved based on the selection of the appropriate harvesting...

  16. Production and cost of harvesting, processing, and transporting small-diameter (< 5 inches) trees for energy

    Science.gov (United States)

    Fei Pan; Han-Sup Han; Leonard R. Johnson; William J. Elliot

    2008-01-01

    Dense, small-diameter stands generally require thinning from below to improve fire-tolerance. The resulting forest biomass can be used for energy production. The cost of harvesting, processing, and transporting small-diameter trees often exceeds revenues due to high costs associated with harvesting and transportation and low market values for forest biomass....

  17. Comparison of six green chile (capsicum annum) cultivars for efficiency of Etgar® machine harvest

    Science.gov (United States)

    As U.S. demand for fresh market green chile rises green chile acreage in the U.S. is declining due to limited availability and high cost of hand labor to harvest it. Many farmers are opting to grow crops other than green chile. Green chile is a New Mexican pod-type chile that is harvested when the...

  18. Magnetically levitated autoparametric broadband vibration energy harvesting

    International Nuclear Information System (INIS)

    Kurmann, L.; Jia, Y.; Manoli, Y.; Woias, P.

    2016-01-01

    Some of the lingering challenges within the current paradigm of vibration energy harvesting (VEH) involve narrow operational frequency range and the inevitable non-resonant response from broadband noise excitations. Such VEHs are only suitable for limited applications with fixed sinusoidal vibration, and fail to capture a large spectrum of the real world vibration. Various arraying designs, frequency tuning schemes and nonlinear vibratory approaches have only yielded modest enhancements. To fundamentally address this, the paper proposes and explores the potentials in using highly nonlinear magnetic spring force to activate an autoparametric oscillator, in order to realize an inherently broadband resonant system. Analytical and numerical modelling illustrate that high spring nonlinearity derived from magnetic levitation helps to promote the 2:1 internal frequency matching required to activate parametric resonance. At the right internal parameters, the resulting system can intrinsically exhibit semi-resonant response regardless of the bandwidth of the input vibration, including broadband white noise excitation. (paper)

  19. An evaluation of harvesting machinery for short rotation coppice willow in Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Kofman, P.D.; Spinelli, R.

    1997-12-31

    During the harvesting seasons 1994-1995 and 1995-1996 several harvesting trials were carried out within the EU project on harvesting and storage of Short Rotation Crops and within a national project. During this period the following machines were investigated: Diemelstadt poplar harvester, cut and chip; Claas forage harvester with SRF header, cut and chip; Austoft sugarcane harvester, adapted to SRF, cut and chip; Bender II, cut and chip; Hvidsted Energy Allrounder, whole shoot harvester; Dansalix whole shoot harvester. In the 1994-1995 season the intention was to harvest 300 tonnes of whole shoots, chunks and chips for a storage trial. The main conclusions of the 1994-1995 harvesting season must be that harvesting willow with the existing machines in wet winters without frozen ground is very difficult. The machines will have to be developed further and special interest should be given to developing shuttle vehicles with the same flotation as the tracked harvester. Several of the problems encountered with the machines in Denmark were confirmed by the experience in the other trials. Road transportation of chips from SRF plantations is just as expensive as transporting energy chips from the forest at about Dkr 50 per tonne over 48 km. Transporting whole shoots is very expensive due to the low bulk density. Transportation of whole shoots over 48 km costs on the average Dkr 133 per tonne fresh. A very short pilot study into chipping of whole shoots from a three metre high pile indicated that this comminution with a normal forest chipper has a low productivity (8.9 tonnes fresh per work place hour) and is very expensive at Dkr 157 per tonne. This productivity can be improved by equipping the chipper with a special feeding table and better feed rollers for the SRF crop. (EG)

  20. Distribution and derivation of white-winged dove harvests in Texas

    KAUST Repository

    Collier, Bret A.; Skow, Kevin L.; Kremer, Shelly R.; Mason, Corey D.; Snelgrove, Robert T.; Calhoun, Kirby W.

    2012-01-01

    Band recoveries provide requisite data for evaluating the spatial distribution of harvest relative to the distribution of breeding stocks for a wide variety of migratory species. We used direct and indirect band-recovery data to evaluate the distribution and derivation of harvest of white-winged doves (Zenaida asiatica) banded before hunting season in 3 distinct strata in Texas, USA, during 2007-2010. We banded 60,742 white-winged doves during 2007-2010, and based on 2,458 harvest recoveries, the majority (>95%) of white-winged dove harvest occurred during the first 2 months of the hunting season (Sep-Oct). Juvenile white-winged doves represented a greater percentage of the direct recoveries than adults across all strata (north = 80%, central = 69%, south = 82%) and the majority of direct band recoveries (north = 75%, central = 90%, south = 78%) occurred within the original banding strata. Age-specific weighting factors and harvest derivation indicated that both juvenile and adult harvest were highest within the strata of original banding. Harvest distribution data corrected for band-reporting rates indicated high fidelity of white-winged doves to specific geographic strata, with little interplay between strata. Our results suggest that population vital-rate estimates for survival and harvest for use in future Adaptive Harvest Management should focus on stock-specific levels. © 2012 The Wildlife Society.

  1. Finite element modeling of nonlinear piezoelectric energy harvesters with magnetic interaction

    International Nuclear Information System (INIS)

    Upadrashta, Deepesh; Yang, Yaowen

    2015-01-01

    Piezoelectric energy harvesting from ambient vibrations is a potential technology for powering wireless sensors and low power electronic devices. The conventional linear harvesters suffer from narrow operational bandwidth. Many attempts have been made especially using the magnetic interaction to broaden the bandwidth of harvesters. The finite element (FE) modeling has been used only for analyzing the linear harvesters in the literature. The main difficulties in extending the FE modeling to analyze the nonlinear harvesters involving magnetic interaction are developing the mesh needed for magnetic interaction in dynamic problems and the high demand on computational resource needed for solving the coupled electrical–mechanical–magnetic problem. In this paper, an innovative method is proposed to model the magnetic interaction without inclusion of the magnetic module. The magnetic force is modeled using the nonlinear spring element available in ANSYS finite element analysis (FEA) package, thus simplifying the simulation of nonlinear piezoelectric energy harvesters as an electromechanically coupled problem. Firstly, an FE model of a monostable nonlinear harvester with cantilever configuration is developed and the results are validated with predictions from the theoretical model. Later, the proposed technique of FE modeling is extended to a complex 2-degree of freedom nonlinear energy harvester for which an accurate analytical model is difficult to derive. The performance predictions from FEA are compared with the experimental results. It is concluded that the proposed modeling technique is able to accurately analyze the behavior of nonlinear harvesters with magnetic interaction. (paper)

  2. Distribution and derivation of white-winged dove harvests in Texas

    KAUST Repository

    Collier, Bret A.

    2012-04-25

    Band recoveries provide requisite data for evaluating the spatial distribution of harvest relative to the distribution of breeding stocks for a wide variety of migratory species. We used direct and indirect band-recovery data to evaluate the distribution and derivation of harvest of white-winged doves (Zenaida asiatica) banded before hunting season in 3 distinct strata in Texas, USA, during 2007-2010. We banded 60,742 white-winged doves during 2007-2010, and based on 2,458 harvest recoveries, the majority (>95%) of white-winged dove harvest occurred during the first 2 months of the hunting season (Sep-Oct). Juvenile white-winged doves represented a greater percentage of the direct recoveries than adults across all strata (north = 80%, central = 69%, south = 82%) and the majority of direct band recoveries (north = 75%, central = 90%, south = 78%) occurred within the original banding strata. Age-specific weighting factors and harvest derivation indicated that both juvenile and adult harvest were highest within the strata of original banding. Harvest distribution data corrected for band-reporting rates indicated high fidelity of white-winged doves to specific geographic strata, with little interplay between strata. Our results suggest that population vital-rate estimates for survival and harvest for use in future Adaptive Harvest Management should focus on stock-specific levels. © 2012 The Wildlife Society.

  3. Wideband Piezomagnetoelastic Vibration Energy Harvesting

    DEFF Research Database (Denmark)

    Lei, Anders; Thomsen, Erik Vilain

    2014-01-01

    This work presents a small-scale wideband piezomagnetoelastic vibration energy harvester (VEH) aimed for operation at frequencies of a few hundred Hz. The VEH consists of a tape-casted PZT cantilever with thin sheets of iron foil attached on each side of the free tip. The wideband operation...... is achieved by placing the cantilever in a magnetic field induced by either one or two magnets located oppositely of the cantilever. The attraction force created by the magnetic field and iron foils introduces a mechanical force in opposite direction of the cantilevers restoring force causing a spring...

  4. Integration with Energy Harvesting Technology

    Directory of Open Access Journals (Sweden)

    S. Williams

    2012-11-01

    Full Text Available This paper reports on the design and implementation of a wireless sensor communication system with a low power consumption that allows it to be integrated with the energy harvesting technology. The system design and implementation focus on reducing the power consumption at three levels: hardware, software and data transmission. The reduction in power consumption, at hardware level in particular, is mainly achieved through the introduction of an energy-aware interface (EAI that ensures a smart inter-correlated management of the energy flow. The resulted system satisfies the requirements of a wireless sensor structure that possesses the energy autonomous capability.

  5. Tree production in desert regions using effluent and water harvesting

    Science.gov (United States)

    Martin M. Karpiscak; Gerald J. Gottfried

    2000-01-01

    Treated municipal effluent combined with water harvesting can be used for land restoration and enhancing the growth of important riparian tree species. Paired studies in Arizona are assessing the potential of growing trees using mixtures of effluent and potable water. Trees are grown in the field and in containers. Initial results from the field show high survival for...

  6. RB962962, a sugarcane cultivar for late harvest

    Directory of Open Access Journals (Sweden)

    Luiz José Oliveira Tavares de Melo

    2014-07-01

    Full Text Available In the Northeast of Brazil, sugarcane cultivar RB962962 is harvested at the end of the cycle, between December and February, with a high sugar yield per area. Recommended for sandy soils of medium texture and fertility, it is resistant to the major diseases and fast-growing in plant and ratoon crops.

  7. Flow Energy Piezoelectric Bimorph Nozzle Harvester

    Science.gov (United States)

    Sherrit, Stewart (Inventor); Walkemeyer, Phillip E. (Inventor); Hall, Jeffrey L. (Inventor); Lee, Hyeong Jae (Inventor); Colonius, Tim (Inventor); Tosi, Phillipe (Inventor); Kim, Namhyo (Inventor); Sun, Kai (Inventor); Corbett, Thomas Gary (Inventor); Arrazola, Alvaro Jose (Inventor)

    2016-01-01

    A flow energy harvesting device having a harvester pipe includes a flow inlet that receives flow from a primary pipe, a flow outlet that returns the flow into the primary pipe, and a flow diverter within the harvester pipe having an inlet section coupled to the flow inlet, a flow constriction section coupled to the inlet section and positioned at a midpoint of the harvester pipe and having a spline shape with a substantially reduced flow opening size at a constriction point along the spline shape, and an outlet section coupled to the constriction section. The harvester pipe may further include a piezoelectric structure extending from the inlet section through the constriction section and point such that the fluid flow past the constriction point results in oscillatory pressure amplitude inducing vibrations in the piezoelectric structure sufficient to cause a direct piezoelectric effect and to generate electrical power for harvesting.

  8. Rooftop level rainwater harvesting system

    Science.gov (United States)

    Traboulsi, Hayssam; Traboulsi, Marwa

    2017-05-01

    Unfortunately, in Lebanon and other countries in the Middle East region, water becomes scarcer than ever before, and over the last decades the demand on domestic water has increased due to population and economic growth. Although rainwater harvesting is considered to be a safe and reliable alternative source for domestic water, the inconvenience or impracticalities related to the cost and space needed for the construction of ground or underground storage tanks makes this practice not widely common in rural areas and rarely implemented in urban cities. This paper introduces a new technique to rainwater harvesting which can be easily used in both rural and urban areas: it collects and stores rainwater directly in tanks already installed on building roofs and not necessarily in special ground or underground ones. If widely adopted in Lebanon, this technique could help in: (1) collecting around 23 MCM (70 % of the current deficit in the domestic water supply) of rainwater and thus increasing the available water per m2 of building by 0.4 m3 per year, (2) saving around 7 % of the amount of electric energy usually needed to pump water from an aquifer well and ground or underground tank, and (3) considerably reducing the rate of surface runoff of rainwater at the coastal zones where rainwater is not captured at all and goes directly to the sea.

  9. Characterization of Piezoelectric Energy Harvesting MEMS

    Science.gov (United States)

    2015-12-01

    of previously fabricated MEMS piezoelectric energy harvesters and use the results to optimize an advanced finite element model to be used in...possibilities of using solar power and the piezoelectric effect to harvest energy [12]. The design goal was to develop an energy harvester with a resonant... The piezoelectric properties of AlN are also relatively constant over a wide range of temperatures [7]. AlN was further characterized

  10. Factors affecting unintentional harvesting selectivity in a monomorphic species.

    Science.gov (United States)

    Bunnefeld, Nils; Baines, David; Newborn, David; Milner-Gulland, E J

    2009-03-01

    1. Changes in the abundance of populations have always perplexed ecologists but long-term studies are revealing new insights into population dynamic processes. Long-term data are often derived from harvest records although many wild populations face high harvesting pressures leading to overharvesting and extinction. Additionally, harvest records used to describe population processes such as fluctuations in abundance and reproductive success often assume a random off-take. 2. Selective harvesting based on phenotypic characteristics occurs in many species (e.g. trophy hunting, fisheries) and has important implications for population dynamics, conservation and management. 3. In species with no marked morphological differences between the age and sex classes, such as the red grouse Lagopus lagopus scoticus during the shooting season, hunters cannot consciously select for a specific sex or age class during the shooting process but harvest records could still give a biased reflection of the population structure because of differences in behaviour between age and sex classes. 4. This study compared age and sex ratios in the bag with those in the population before shooting for red grouse at different points in the shooting season and different densities, which has rarely been tested before. 5. More young than old grouse were shot at large bag sizes and vice versa for small bag sizes than would be expected from the population composition before shooting. The susceptibility of old males to shooting compared to females increased with bag size and was high at the first time the area was shot but decreased with the number of times an area was harvested. 6. These findings stress that the assumption made in many studies that harvest records reflect the age and sex ratio of the population and therefore reflect productivity can be misleading. 7. In this paper, as in the literature, it is also shown that number of grouse shot reflects grouse density and therefore that hunting

  11. Apparatus and method for harvesting woody plantations

    Science.gov (United States)

    Eggen, D.L.

    1988-11-15

    A tree harvester for harvesting felled trees includes a wheel mounted wood chipper which moves toward the butt ends of the tree stems to be processed. The harvester includes a plurality of rotating alignment discs in front of the chipper. These discs align the tree stems to be processed with the mouth of the chipper. A chipper infeed cylinder is rotatably mounted between the discs and the front end of the chipper, and lifts the tree stem butts up from the ground into alignment with the chipper inlet port. The chips discharge from the chipper and go into a chip hopper which moves with the tree harvester. 8 figs.

  12. Energy-Harvesting Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Fafoutis, Xenofon; Vuckovic, Dusan; Di Mauro, Alessio

    2012-01-01

    Energy Harvesting comprises a promising solution to one of the key problems faced by battery-powered Wireless Sensor Networks, namely the limited nature of the energy supply (finite battery capacity). By harvesting energy from the surrounding environment, the sensors can have a continuous lifetime...... Sensor Networks with energy harvesting capability....... without any needs for battery recharge or replacement. However, energy harvesting introduces a change to the fundamental principles based on which WSNs are designed and realized. In this poster we sketch some of the key research challenges as well as our ongoing work in designing and realizing Wireless...

  13. REVISITED GRAIN HARVESTERS PARAMETERS SUBSTATIATION AND EFFECTIVENESS OF THEM

    Directory of Open Access Journals (Sweden)

    G. G. Maslov

    2016-01-01

    Full Text Available Impact of cereal crops yield on the actual strow content in heap mass was studied. Its distribution interval is from 0.6 to 1.2 in the range of yields from 3 to 12 t/ha. Regularity of strow content decline and productivity increase at the same time is confirmed by the Cochran criterion (its estimated value of 0.56 is less than the table one of 0.62. A strow content low facilitates the harvesters’ operation. The required for the operation process harvesters engine power is different depending on schemes of threshing-separating machine with the rotary and beater threshing drums. The authors proved adequacy of the obtained mathematical models of dependence of the engine power from harvester delivery capacity. For the combines with classical technological scheme the calculated value of Fisher criterion is 0.75. For combines with an axial rotary threshing-separating device the table value of 0.8 criterion is also higher than the estimated one of 0.66.The obtained results of the required power calculations at various methodological approaches were close to results convergence exceeding 10 percent, which confirms objectivity of them. The technological and economic efficiency of the rotary harvesters compared with classical scheme is better. It is obtained due to the higher specific bandwidth, low grain crushing and micro damage. If a harvester has the threshing-separating device with axial rotor scheme, so grain crushing is much less(no more than 0.5-0.6 percent, which also improves economic parameters. But at operation of combines with the classical scheme the share of broken grain makes 4-6 percent that sharply raises indirect losses of a harvest. We recommend when the combine fleet renovation шт agricultural enterprises to introduce 1.5-2 times high-performance harvesters with axial rotor scheme.

  14. Light-harvesting organic photoinitiators of polymerization.

    Science.gov (United States)

    Lalevée, Jacques; Tehfe, Mohamad-Ali; Dumur, Frédéric; Gigmes, Didier; Graff, Bernadette; Morlet-Savary, Fabrice; Fouassier, Jean-Pierre

    2013-02-12

    Two new photoinitiators with unprecedented light absorption properties are proposed on the basis of a suitable truxene skeleton where several UV photoinitiators PI units such as benzophenone and thioxanthone are introduced at the periphery and whose molecular orbitals MO can be coupled with those of the PI units: a red-shifted absorption and a strong increase of the molecular extinction coefficients (by a ≈ 20-1000 fold factor) are found. These compounds are highly efficient light-harvesting photoinitiators. The scope and practicality of these photoinitiators of polymerization can be dramatically expanded, that is, both radical and cationic polymerization processes are accessible upon very soft irradiation conditions (halogen lamp, LED…︁) thanks to the unique light absorption properties of the new proposed structures. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. PS2004 Light-harvesting Systems Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Blankenship, Robert E.

    2005-01-01

    This special issue of the international scientific research journal Photosynthesis Research consists of 25 original peer-reviewed contributions from participants in the PS 2004 Lisht-Harvesting Systems Workshop. This workshop was held from 26-29, 2004 at Hotel Le Chantecler, Sainte-Adele, Quebec, Canada. The workshop was a satellite meeting of the XIII International Congress on Photosynthesis held August 29-September 3, 2004 in Montreal, Canada. The workshope dealt with all types of photosynthetic antenna systems and types of organisms, including anoxygenic photosynthetic bacteria, cyanobacteria, algae and higher plants, as well as in vitro studies of isolated pigments. This collection of papers is a good representation of the highly interdisciplinary nature of modern research on photosynthetic antenna complexes, utilizing techniques of advanced spectroscopy, biochemistry, molecular biology, synthetic chemistry and structural determination to understand these diverse and elegant molecular complexes.

  16. Response of a tropical tree to non-timber forest products harvest and reduction in habitat size

    Science.gov (United States)

    Kouagou, M’Mouyohoun; Natta, Armand K.; Gado, Choukouratou

    2017-01-01

    Non-timber forest products (NTFPs) are widely harvested by local people for their livelihood. Harvest often takes place in human disturbed ecosystems. However, our understanding of NTFPs harvesting impacts in fragmented habitats is limited. We assessed the impacts of fruit harvest, and reduction in habitat size on the population structures of Pentadesma butyracea Sabine (Clusiaceae) across two contrasting ecological regions (dry vs. moist) in Benin. In each region, we selected three populations for each of the three fruit harvesting intensities (low, medium and high). Harvesting intensities were estimated as the proportion of fruits harvested per population. Pentadesma butyracea is found in gallery forests along rivers and streams. We used the width of gallery forests as a measure of habitat size. We found negative effects of fruit harvest on seedling and adult density but no significant effect on population size class distribution in both ecological regions. The lack of significant effect of fruit harvest on population structure may be explained by the ability of P. butyracea to compensate for the negative effect of fruit harvesting by increasing clonal reproduction. Our results suggest that using tree density and population structure to assess the ecological impacts of harvesting clonal plants should be done with caution. PMID:28850624

  17. Response of a tropical tree to non-timber forest products harvest and reduction in habitat size.

    Directory of Open Access Journals (Sweden)

    Orou G Gaoue

    Full Text Available Non-timber forest products (NTFPs are widely harvested by local people for their livelihood. Harvest often takes place in human disturbed ecosystems. However, our understanding of NTFPs harvesting impacts in fragmented habitats is limited. We assessed the impacts of fruit harvest, and reduction in habitat size on the population structures of Pentadesma butyracea Sabine (Clusiaceae across two contrasting ecological regions (dry vs. moist in Benin. In each region, we selected three populations for each of the three fruit harvesting intensities (low, medium and high. Harvesting intensities were estimated as the proportion of fruits harvested per population. Pentadesma butyracea is found in gallery forests along rivers and streams. We used the width of gallery forests as a measure of habitat size. We found negative effects of fruit harvest on seedling and adult density but no significant effect on population size class distribution in both ecological regions. The lack of significant effect of fruit harvest on population structure may be explained by the ability of P. butyracea to compensate for the negative effect of fruit harvesting by increasing clonal reproduction. Our results suggest that using tree density and population structure to assess the ecological impacts of harvesting clonal plants should be done with caution.

  18. Rainwater harvesting - An investigation into the potential for rainwater harvesting in Bradford

    OpenAIRE

    Doncaster, S.; Blanksby, J.; Shepherd, W.

    2012-01-01

    This report provides a brief review of rainwater harvesting and rainwater harvesting tools, which are then used in case study examples for domestic, office block and warehouse rain water harvesting scenarios. Rainwater harvesting is placed in an historical context as a source of water supply and in a modern context as being complementary to centralised water distribution networks with benefits for wider water management including flood risk treatment as well as providing environmental and eco...

  19. Harvesting energy from airflow with a michromachined piezoelectric harvester inside a Helmholtz resonator

    NARCIS (Netherlands)

    Matova, S.P.; Elfrink, R.; Vullers, R.J.M.; Schaijk, R. van

    2011-01-01

    In this paper we report an airflow energy harvester that combines a piezoelectric energy harvester with a Helmholtz resonator. The resonator converts airflow energy to air oscillations which in turn are converted into electrical energy by a piezoelectric harvester. Two Helmholtz resonators with

  20. Effect of time of harvest, stage of fruit ripening, and post-harvest ...

    African Journals Online (AJOL)

    Seeds were extracted from half of the fruits harvested from each stage immediately after harvest while the other halves were stored at room temperature to ripen to the soft-red stage before seed extraction. Fruit weight in both cultivars decreased with plant age. Fruits harvested at the yellow-ripe stage produced the highest ...

  1. A new harvest operation cost model to evaluate forest harvest layout alternatives

    Science.gov (United States)

    Mark M. Clark; Russell D. Meller; Timothy P. McDonald; Chao Chi Ting

    1997-01-01

    The authors develop a new model for harvest operation costs that can be used to evaluate stands for potential harvest. The model is based on felling, extraction, and access costs, and is unique in its consideration of the interaction between harvest area shapes and access roads. The scientists illustrate the model and evaluate the impact of stand size, volume, and road...

  2. Harvesting and replenishment policies for renewable natural resources

    Science.gov (United States)

    Douglas, Aaron J.; Johnson, Richard L.

    1993-01-01

    The current paper links the optimal intertemporal use of renewable natural resources to the harvesting activities of various economic agents. Previous contributions cite market forces as a causative factor inducing the extirpation of renewable natural resources. The analysis given here discusses investment in the stock of renewable resources and cites important examples of this activity. By introducing joint harvesting and replenishment strategies into a model of renewable resource use, the analysis adds descriptive reality and relevance to positive and normative discussions of renewable natural resource use. A high price for the yield or a high discount rate tend to diminish the size of the optimum stationary stock of the resource with a non-replenishment harvesting strategy. Optimal non-replenishment harvesting strategies for renewable natural resources will exhaustion or extirpation of the resource if the price of the yield or the discount rate are sufficiently large. However, the availability of a replenishment technology and the use of replenishment activities tends to buffer the resource against exhaustion or extirpation.

  3. A triple hybrid micropower generator with simultaneous multi-mode energy harvesting

    Science.gov (United States)

    Uluşan, H.; Chamanian, S.; Pathirana, W. P. M. R.; Zorlu, Ö.; Muhtaroğlu, A.; Külah, H.

    2018-01-01

    This study presents a triple hybrid energy harvesting system that combines harvested power from thermoelectric (TE), vibration-based electromagnetic (EM) and piezoelectric (PZT) harvesters into a single DC supply. A power management circuit is designed and implemented in 180 nm standard CMOS technology based on the distinct requirements of each harvester, and is terminated with a Schottky diode to avoid reverse current flow. The system topology hence supports simultaneous power generation and delivery from low and high frequency vibrations as well as temperature differences in the environment. The ultra-low DC voltage harvested from TE generator is boosted with a cross-coupled charge-pump driven by an LC oscillator with fully-integrated center-tapped differential inductors. The EM harvester output was rectified with a self-powered and low drop-out AC/DC doubler circuit. The PZT interface electronics benefits from peak-to-peak cycle of the harvested voltage through a negative voltage converter followed by synchronous power extraction and DC-to-DC conversion through internal switches, and an external inductor. The hybrid system was tested with a wearable in-house EM energy harvester placed wrist of a jogger, a commercial low volume PZT harvester, and DC supply as the TE generator output. The system generates more than 1.2 V output for load resistances higher than 50 kΩ, which corresponds to 24 μW to power wearable sensors. Simultaneous multi-mode operation achieves higher voltage and power compared to stand-alone harvesting circuits, and generates up to 110 μW of output power. This is the first hybrid harvester circuit that simultaneously extracts energy from three independent sources, and delivers a single DC output.

  4. Identifying yield-optimizing environments for two cowpea breeding lines by manipulating photoperiod and harvest scenario

    Science.gov (United States)

    Ohler, T. A.; Mitchell, C. A.

    1996-01-01

    Photoperiod and harvest scenario of cowpea (Vigna unguiculata L. Walp) canopies were manipulated to optimize productivity for use in future controlled ecological life-support systems. Productivity was measured by edible yield rate (EYR:g m-2 day-1), shoot harvest index (SHI: g edible biomass [g total shoot dry weight]), and yield-efficiency rate (YER:g edible biomass m-2 day-1 per[g nonedible shoot dry weight]). Breeding lines 'IT84S-2246' (S-2246) and "IT82D-889' (D-889) were grown in a greenhouse under 8-, 12-, or 24-h photoperiods. S-2246 was short-day and D-889 was day-neutral for flowering. Under each photoperiod, cowpeas were harvested either for leaves only, seeds only, or leaves plus seeds (mixed harvest). Photoperiod did not affect EYR of either breeding line for any harvest scenario tested. Averaged over both breeding lines, seed harvest gave the highest EYR at 6.7 g m-2 day-1. The highest SHI (65%) and YER (94 mg m-2 day-1 g-1) were achieved for leaf-only harvest of D-889 under an 8-h photoperiod. For leaf-only harvest of S-2246, both SHI and YER increased with increasing photoperiod, but declined for seed-only and mixed harvests. However, photoperiod had no effect on SHI or YER for D-889 for any harvest scenario. A second experiment utilized the short-day cowpea breeding line 'IT89KD-288' (D-288) and the day-neutral breeding line 'IT87D-941-1' (D-941) to compare yield parameters using photoperiod extension under differing lamp types. This experiment confirmed the photoperiod responses of D-889 and S-2246 to a mixed-harvest scenario and indicated that daylength extension with higher irradiance from high pressure sodium lamps further suppressed EYR, SHI, and YER of the short-day breeding line D-288.

  5. Energy and industrial wood harvesting from young forests; Energia- ja ainespuun korjuu nuorista metsistae

    Energy Technology Data Exchange (ETDEWEB)

    Rieppo, K.; Mutikainen, A.; Jouhiaho, A. (eds.)

    2011-07-01

    In the METKA Forest Energy Profitably project TTS (Work Efficiency Institute) compared methods suitable for the harvesting of energy wood and industrial wood. During the thinning of a young forest by a forest worker, the whole-tree logging method was one-third less expensive than the pulpwood method, including terrain transport. In harvesting whole trees as part of the thinning of young forests, methods based on combinations of manual and mechanized workproved to be several dozen per cent less expensive than the entirely mechanized method. When cutting energy wood with a Harveri small harwarder productivity was slightly higher when using 40-metre distances two cutting trails than when using 20-metre distances. When using a Tehojaetkae small harvester, creating two cutting trails in addition to the standard four-metre-wide cutting trail resulted in slightly higher productivity than creating three narrow cutting trails. A Risutec L3A energy head was used in tests involving both clearing and energy wood cutting. This method proved to be very promising, and it seems highly proable that advance clearing will no longer be needed in energy wood harvesting under all circumstances. When using traditional harvester-forwarder chains and a harvarder for first thinning in pine stands, the harvesting of entirely or partly non-delimbed trees was 20 to 40 per cent less expensive per harvested cubic meter than the harvesting of delimbed trees. In tests carried out using the Naarva RS25 harvester head for first thinning in pine stands, the integrated method resulted in approximately one-third productivity than the traditional cutting of industrial wood. In a spruce-dominant site with delayed first thinning, the unit costs of harvesting delimbed energy wood were 16 per cent lower than those of the harvesting of pulpwood. In the future development of machinery, it will be important to aim at continuous motion, at least in terms of cutting small trees. (orig.)

  6. Profitability of wood harvesting enterprises

    Energy Technology Data Exchange (ETDEWEB)

    Penttinen, M. email: markku.penttinen@metla.fi; Mikkola, J. email: jarmo.mikkola@metla.fi; Rummukainen, A. email: arto.rummukainen@metla.fi

    2009-07-01

    The forest machine business is about 50 years old. The rapid technical development of machinery increased productivity up to the end of last century. In 2007, the total value of round and energy wood harvesting and silvicultural work operated by forest machine enterprises exceeded 570 mill. euro. According to the materials of the Vehicle Administration Finland and Statistics Finland there are about 1 600 active harvesting enterprises in the personal and business taxation system. Beside this, there are according to the Ministry of Agriculture and Forestry about 1 300 farmers who do harvesting as side business. About 1 000 enterprises working in June 2007 were studied with their retrospective economic analyses from 2001. The data includes all enterprises that had supplied closing of the accounts data. One-machine entrepreneurs represent more than a third of the number of enterprises, but only 13 percent of the turnover. Enterprises with seven or more machines represent less than ten percent of the number, but over twenty percent of the turnover. Enterprises are largest in eastern and northern Finland, where the average number of machines per enterprise exceeds three. Small enterprises are mostly singleowner business enterprises with a median turnover of 125 000 euros per annum. Partnerships and limited enterprises have double the median turnover of single-owner businesss. Limited companies turn over a median of 450 000 euro/y, representing 67 percent of total turnover. Median net profit varied between 6 and 10 percent of turnover in 2001-2007, but only between 2 and 4 percent where the wage adjustment is deducted from the profit. The wage adjustment is estimated as if the owners of single-owner businesses earn an operator's salary. Profit was highest in 2002 and lowest 2006. In the smallest enterprise class with a turnover of less than 75 000 euro/y, profit was lowest and negative in 2006 and 2007. The variation in profits between enterprises was also biggest in

  7. Light Harvesting for Organic Photovoltaics

    Science.gov (United States)

    2016-01-01

    The field of organic photovoltaics has developed rapidly over the last 2 decades, and small solar cells with power conversion efficiencies of 13% have been demonstrated. Light absorbed in the organic layers forms tightly bound excitons that are split into free electrons and holes using heterojunctions of electron donor and acceptor materials, which are then extracted at electrodes to give useful electrical power. This review gives a concise description of the fundamental processes in photovoltaic devices, with the main emphasis on the characterization of energy transfer and its role in dictating device architecture, including multilayer planar heterojunctions, and on the factors that impact free carrier generation from dissociated excitons. We briefly discuss harvesting of triplet excitons, which now attracts substantial interest when used in conjunction with singlet fission. Finally, we introduce the techniques used by researchers for characterization and engineering of bulk heterojunctions to realize large photocurrents, and examine the formed morphology in three prototypical blends. PMID:27951633

  8. Biogenesis of light harvesting proteins.

    Science.gov (United States)

    Dall'Osto, Luca; Bressan, Mauro; Bassi, Roberto

    2015-09-01

    The LHC family includes nuclear-encoded, integral thylakoid membrane proteins, most of which coordinate chlorophyll and xanthophyll chromophores. By assembling with the core complexes of both photosystems, LHCs form a flexible peripheral moiety for enhancing light-harvesting cross-section, regulating its efficiency and providing protection against photo-oxidative stress. Upon its first appearance, LHC proteins underwent evolutionary diversification into a large protein family with a complex genetic redundancy. Such differentiation appears as a crucial event in the adaptation of photosynthetic organisms to changing environmental conditions and land colonization. The structure of photosystems, including nuclear- and chloroplast-encoded subunits, presented the cell with a number of challenges for the control of the light harvesting function. Indeed, LHC-encoding messages are translated in the cytosol, and pre-proteins imported into the chloroplast, processed to their mature size and targeted to the thylakoids where are assembled with chromophores. Thus, a tight coordination between nuclear and plastid gene expression, in response to environmental stimuli, is required to adjust LHC composition during photoacclimation. In recent years, remarkable progress has been achieved in elucidating structure, function and regulatory pathways involving LHCs; however, a number of molecular details still await elucidation. In this review, we will provide an overview on the current knowledge on LHC biogenesis, ranging from organization of pigment-protein complexes to the modulation of gene expression, import and targeting to the photosynthetic membranes, and regulation of LHC assembly and turnover. Genes controlling these events are potential candidate for biotechnological applications aimed at optimizing light use efficiency of photosynthetic organisms. This article is part of a Special Issue entitled: Chloroplast biogenesis. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Towards Complete Coverage in Focused Web Harvesting

    NARCIS (Netherlands)

    Khelghati, Mohammadreza; Hiemstra, Djoerd; van Keulen, Maurice

    2015-01-01

    With the goal of harvesting all information about a given entity, in this paper, we try to harvest all matching documents for a given query submitted on a search engine. The objective is to retrieve all information about for instance "Michael Jackson", "Islamic State", or "FC Barcelona" from indexed

  10. Ultrasound acoustic wave energy transfer and harvesting

    Science.gov (United States)

    Shahab, Shima; Leadenham, Stephen; Guillot, François; Sabra, Karim; Erturk, Alper

    2014-04-01

    This paper investigates low-power electricity generation from ultrasound acoustic wave energy transfer combined with piezoelectric energy harvesting for wireless applications ranging from medical implants to naval sensor systems. The focus is placed on an underwater system that consists of a pulsating source for spherical wave generation and a harvester connected to an external resistive load for quantifying the electrical power output. An analytical electro-acoustic model is developed to relate the source strength to the electrical power output of the harvester located at a specific distance from the source. The model couples the energy harvester dynamics (piezoelectric device and electrical load) with the source strength through the acoustic-structure interaction at the harvester-fluid interface. Case studies are given for a detailed understanding of the coupled system dynamics under various conditions. Specifically the relationship between the electrical power output and system parameters, such as the distance of the harvester from the source, dimensions of the harvester, level of source strength, and electrical load resistance are explored. Sensitivity of the electrical power output to the excitation frequency in the neighborhood of the harvester's underwater resonance frequency is also reported.

  11. Dielectric loss against piezoelectric power harvesting

    Science.gov (United States)

    Liang, Junrui; Shu-Hung Chung, Henry; Liao, Wei-Hsin

    2014-09-01

    Piezoelectricity is one of the most popular electromechanical transduction mechanisms for constructing kinetic energy harvesting systems. When a standard energy harvesting (SEH) interface circuit, i.e., bridge rectifier plus filter capacitor, is utilized for collecting piezoelectric power, the previous literature showed that the power conversion can be well predicted without much consideration for the effect of dielectric loss. Yet, as the conversion power gets higher by adopting power-boosting interface circuits, such as synchronized switch harvesting on inductor (SSHI), the neglect of dielectric loss might give rise to deviation in harvested power estimation. Given the continuous progress on power-boosting interface circuits, the role of dielectric loss in practical piezoelectric energy harvesting (PEH) systems should receive attention with better evaluation. Based on the integrated equivalent impedance network model, this fast track communication provides a comprehensive study on the susceptibility of harvested power in PEH systems under different conditions. It shows that, dielectric loss always counteracts piezoelectric power harvesting by causing charge leakage across piezoelectric capacitance. In particular, taking corresponding ideal lossless cases as references, the counteractive effect might be aggravated under one of the five conditions: larger dielectric loss tangent, lower vibration frequency, further away from resonance, weaker electromechanical coupling, or using power-boosting interface circuit. These relationships are valuable for the study of PEH systems, as they not only help explain the role of dielectric loss in piezoelectric power harvesting, but also add complementary insights for material, structure, excitation, and circuit considerations towards holistic evaluation and design for practical PEH systems.

  12. Setting analyst: A practical harvest planning technique

    Science.gov (United States)

    Olivier R.M. Halleux; W. Dale Greene

    2001-01-01

    Setting Analyst is an ArcView extension that facilitates practical harvest planning for ground-based systems. By modeling the travel patterns of ground-based machines, it compares different harvesting settings based on projected average skidding distance, logging costs, and site disturbance levels. Setting Analyst uses information commonly available to consulting...

  13. Determinants of rainwater harvesting technology (RWHT) adoption ...

    African Journals Online (AJOL)

    2014-11-26

    Nov 26, 2014 ... study evaluated the determinants of farmers' decisions to adopt rainwater harvesting technology ... adoption of RWHT in the study area. ... In South Africa, agriculture involves large numbers of ... Study area and data collection ..... study in rainwater harvesting: A 2011 perspective. ... Kluwer Academic.

  14. West Virginia harvest and utilization study, 2008

    Science.gov (United States)

    Jan Wiedenbeck; Shawn. Grushecky

    2014-01-01

    Thirty active harvesting operations were part of a harvest and utilization study conducted in West Virginia in 2008. Data were collected on roundwood product and residue yields obtained from trees of different sizes, species, and qualities. This study was modeled after studies conducted on a regular and frequent basis by the Forest Inventory and Analysis unit in the...

  15. Electromagnetic Power Harvester Using Wide-Angle and Polarization-Insensitive Metasurfaces

    Directory of Open Access Journals (Sweden)

    Xuanming Zhang

    2018-03-01

    Full Text Available A new wide-angle and polarization-insensitive metasurface (MS instead of traditional antenna is built as the primary ambient energy harvester in this paper. The MS is a two-dimensional energy harvesting array that is composed of subwavelength electrical small ring resonator that is working at 2.5 GHz (LTE/WiFi. In the case of different polarization and incidence angles, we demonstrate the metasurface can achieve high harvesting efficiency of 90%. The fabricated prototype of 9 × 9 MS energy harvesting array is measured, and the experimental results validate that the proposed MS has a good performance more than 80% of energy harvesting efficiency for arbitrary polarization and wide-angle incident waves. The good agreement of the simulation with the experiment results verifies the practicability and effectiveness of the proposed MS structure, which will provide a new source of supply in wireless sensor networks (WSN.

  16. Genes controlling seed dormancy and pre-harvest sprouting in a rice-wheat-barley comparison

    DEFF Research Database (Denmark)

    Li, Chengdao; Ni, Peixiang; Francki, Michael

    2004-01-01

    Pre-harvest sprouting results in significant economic loss for the grain industry around the world. Lack of adequate seed dormancy is the major reason for pre-harvest sprouting in the field under wet weather conditions. Although this trait is governed by multiple genes it is also highly heritable....... A major QTL controlling both pre-harvest sprouting and seed dormancy has been identified on the long arm of barley chromosome 5H, and it explains over 70% of the phenotypic variation. Comparative genomics approaches among barley, wheat and rice were used to identify candidate gene(s) controlling seed...... dormancy and hence one aspect of pre-harvest sprouting. The barley seed dormancy/pre-harvest sprouting QTL was located in a region that showed good synteny with the terminal end of the long arm of rice chromosome 3. The rice DNA sequences were annotated and a gene encoding GA20-oxidase was identified...

  17. Piezoelectric energy harvesting from broadband random vibrations

    International Nuclear Information System (INIS)

    Adhikari, S; Friswell, M I; Inman, D J

    2009-01-01

    Energy harvesting for the purpose of powering low power electronic sensor systems has received explosive attention in the last few years. Most works using deterministic approaches focusing on using the piezoelectric effect to harvest ambient vibration energy have concentrated on cantilever beams at resonance using harmonic excitation. Here, using a stochastic approach, we focus on using a stack configuration and harvesting broadband vibration energy, a more practically available ambient source. It is assumed that the ambient base excitation is stationary Gaussian white noise, which has a constant power-spectral density across the frequency range considered. The mean power acquired from a piezoelectric vibration-based energy harvester subjected to random base excitation is derived using the theory of random vibrations. Two cases, namely the harvesting circuit with and without an inductor, have been considered. Exact closed-form expressions involving non-dimensional parameters of the electromechanical system have been given and illustrated using numerical examples

  18. Piezoelectric energy harvesting from broadband random vibrations

    Science.gov (United States)

    Adhikari, S.; Friswell, M. I.; Inman, D. J.

    2009-11-01

    Energy harvesting for the purpose of powering low power electronic sensor systems has received explosive attention in the last few years. Most works using deterministic approaches focusing on using the piezoelectric effect to harvest ambient vibration energy have concentrated on cantilever beams at resonance using harmonic excitation. Here, using a stochastic approach, we focus on using a stack configuration and harvesting broadband vibration energy, a more practically available ambient source. It is assumed that the ambient base excitation is stationary Gaussian white noise, which has a constant power-spectral density across the frequency range considered. The mean power acquired from a piezoelectric vibration-based energy harvester subjected to random base excitation is derived using the theory of random vibrations. Two cases, namely the harvesting circuit with and without an inductor, have been considered. Exact closed-form expressions involving non-dimensional parameters of the electromechanical system have been given and illustrated using numerical examples.

  19. A Miniature Coupled Bistable Vibration Energy Harvester

    International Nuclear Information System (INIS)

    Zhu, D; Arthur, D C; Beeby, S P

    2014-01-01

    This paper reports the design and test of a miniature coupled bistable vibration energy harvester. Operation of a bistable structure largely depends on vibration amplitude rather than frequency, which makes it very promising for wideband vibration energy harvesting applications. A coupled bistable structure consists of a pair of mobile magnets that create two potential wells and thus the bistable phenomenon. It requires lower excitation to trigger bistable operation compared to conventional bistable structures. Based on previous research, this work focused on miniaturisation of the coupled bistable structure for energy harvesting application. The proposed bistable energy harvester is a combination of a Duffing's nonlinear structure and a linear assisting resonator. Experimental results show that the output spectrum of the miniature coupled bistable vibration energy harvester was the superposition of several spectra. It had a higher maximum output power and a much greater bandwidth compared to simply the Duffing's structure without the assisting resonator

  20. Piezoelectric energy harvesting with parametric uncertainty

    International Nuclear Information System (INIS)

    Ali, S F; Friswell, M I; Adhikari, S

    2010-01-01

    The design and analysis of energy harvesting devices is becoming increasing important in recent years. Most of the literature has focused on the deterministic analysis of these systems and the problem of uncertain parameters has received less attention. Energy harvesting devices exhibit parametric uncertainty due to errors in measurement, errors in modelling and variability in the parameters during manufacture. This paper investigates the effect of parametric uncertainty in the mechanical system on the harvested power, and derives approximate explicit formulae for the optimal electrical parameters that maximize the mean harvested power. The maximum of the mean harvested power decreases with increasing uncertainty, and the optimal frequency at which the maximum mean power occurs shifts. The effect of the parameter variance on the optimal electrical time constant and optimal coupling coefficient are reported. Monte Carlo based simulation results are used to further analyse the system under parametric uncertainty

  1. Experimental measurement of energy harvesting with backpack

    Science.gov (United States)

    Pavelkova, Radka; Vala, David; Suranek, Pavel; Mahdal, Miroslav

    2017-08-01

    This article deals with the energy harvesting systems, especially the energy harvesting backpack, which appears as a convenient means for energy harvesting for mobile sensors power. Before starting the experiment, it was necessary to verify whether this energy will be sufficient to get acquainted with the human kinematics and analyze problematics itself. For this purpose there was used motion capture technology from Xsens. Measured data on the position of a particle moving man and back when walking, these data were then used for experimental realization of energy harvesting backpack and as input data to the simulation in Simulink, which brought us a comparison between theoretical assumptions and practical implementation. When measuring characteristics of energy harvesting system we have a problem with measurements on backpack solved when redoing of the hydraulic cylinder as a source of a suitable movement corresponding to the amplitude and frequency of human walk.

  2. Finite element analysis of hybrid energy harvesting of piezoelectric and electromagnetic

    Directory of Open Access Journals (Sweden)

    Muhammad Yazid Muhammad Ammar Faris

    2017-01-01

    Full Text Available Harvesting energy from ambient vibrations is a highly required method because of the wide range of available sources that produce vibration energy application from industrial machinery to human motion application. In this paper, the implementation of harvesting energy from two technologies to form a hybrid energy harvester system was analyzed. These two technologies involve the piezoelectric harvesting energy and the electromagnetic harvesting energy. A finite element model was developed using the Ansys software with the harmonic analysis solver to analyze and examine hybrid harvesting energy system. Both power output generated from the magnet and the piezoelectric is then combined to form one unit of energy. Further, it was found that the result shows the system generate the maximum power output of 14.85 μW from 100 Hz, 4.905 m/s2, and 0.6 cm3 for resonance frequency, acceleration, and the volume respectively from the optimal energy harvester design. Normalized Power Density (NPD result of 10.29 kgs/m3 comparable with other literature also can be used in energy harvesting system for vibration application.

  3. Energy harvesting from arterial blood pressure for powering embedded brain sensors

    Science.gov (United States)

    Nanda, Aditya; Karami, M. Amin

    2016-04-01

    This paper investigates energy harvesting from arterial blood pressure via the piezoelectric effect by using a novel streaked cylinder geometry for the purpose of powering embedded micro-sensors in the brain. Initially, we look at the energy harvested by a piezoelectric cylinder placed inside an artery acted upon by blood pressure. Such an arrangement would be tantamount to constructing a stent out of piezoelectric materials. A stent is a cylinder placed in veins and arteries to prevent obstruction in blood flow. The governing equations of a conductor coated piezoelectric cylinder are obtained using Hamilton's principle. Pressure acting in arteries is radially directed and this is used to simplify the modal analysis and obtain the transfer function relating pressure to the induced voltage across the surface of the harvester. The power harvested by the cylindrical harvester is obtained for different shunt resistances. Radially directed pressure occurs elsewhere and we also look at harvesting energy from oil flow in pipelines. Although the energy harvested by the cylindrical energy harvester is significant at resonance, the natural frequency of the system is found to be very high. To decrease the natural frequency, we propose a novel streaked stent design by cutting it along the length, transforming it to a curved plate and decreasing the natural frequency. The governing equations corresponding to the new geometry are derived using Hamilton's principle and modal analysis is used to obtain the transfer function.

  4. Micro energy harvesting from ambient motion : modeling, simulation and design

    Energy Technology Data Exchange (ETDEWEB)

    Blystad, Lars-Cyril

    2012-07-01

    Vibration energy harvesting is the process of converting available ambient kinetic energy into useful electrical energy. It can be done on large scale with e.g. a wind-driven turbine. This thesis deals with small scale energy harvesters that are suitable for fabrication in Micro electromechanical Systems (MEMS) technologies. Such MEMS energy harvesters have the potential to supply power for micro power devices. Modeling, simulation and design of MEMS vibration energy harvesters are the foci of this thesis. Transduction mechanisms that are covered are electrostatic and piezoelectric. Electric equivalent circuits are obtained for the use in electromechanical simulations with the circuit simulator SPICE. The feasibility of simulating both narrow- and broadband vibrations, to model different external driving forces, in a standard circuit simulator is demonstrated. Comparisons of the har- vesters performance for different excitations are presented. A selection of passive and active power conditioning circuits is investigated and their performances compared. The active nonlinear switching conversion circuitry performs better than simple passive circuitry, especially when mechanical end stops are in effect. The active switching circuits give higher electromechanical damping, and thus can be driven at higher acceleration amplitudes before end stops are engaged. Mechanical end stops have to be present in all MEMS vibrational energy harvesters. Either due to space limitations, reliability issues, Simliberate introduction of nonlinearities or a combination of these. ulations in the thesis include mechanical end stops and thus include the corresponding nonlinearities introduced in the system. When the mechanical end stops are hit by the proof mass during high-amplitude vibrations, nonlinear effects such as saturation and jumps are present. The end stops increase the effective bandwidth at large acceleration amplitudes. End stops limit the output power for sinusoidal

  5. Harvesting energy from airflow with a michromachined piezoelectric harvester inside a Helmholtz resonator

    International Nuclear Information System (INIS)

    Matova, S P; Elfrink, R; Vullers, R J M; Van Schaijk, R

    2011-01-01

    In this paper we report an airflow energy harvester that combines a piezoelectric energy harvester with a Helmholtz resonator. The resonator converts airflow energy to air oscillations which in turn are converted into electrical energy by a piezoelectric harvester. Two Helmholtz resonators with adjustable resonance frequencies have been designed—one with a solid bottom and one with membrane on the bottom. The resonance frequencies of the resonators were matched to the complementing piezoelectric harvesters during harvesting. The aim of the presented work is a feasibility study on using packaged piezoelectric energy harvesters with Helmholtz resonators for airflow energy harvesting. The maximum energy we were able to obtain was 42.2 µW at 20 m s −1

  6. Development of Vibration-Based Piezoelectric Raindrop Energy Harvesting System

    Science.gov (United States)

    Wong, Chin Hong; Dahari, Zuraini

    2017-03-01

    The trend of finding new means to harvest energy has triggered numerous researches to explore the potential of raindrop energy harvesting. This paper presents an investigation on raindrop energy harvesting which compares the performance of polyvinylidene fluoride (PVDF) cantilever and bridge structure transducers and the development of a raindrop energy harvesting system. The parameters which contribute to the output voltage such as droplet size, droplets released at specific heights and dimensions of PVDF transducers are analyzed. Based on the experimental results, the outcomes have shown that the bridge structure transducer generated a higher voltage than the cantilever. Several dimensions have been tested and it was found that the 30 mm × 4 mm × 25 μm bridge structure transducer generated a relatively high AC open-circuit voltage, which is 4.22 V. The power generated by the bridge transducer is 18 μW across a load of 330 kΩ. The transducer is able to drive up a standard alternative current (AC) to direct current (DC) converter (full-wave bridge rectifier). It generated a DC voltage, V DC of 8.7 mV and 229 pW across a 330 kΩ resistor per drop. It is also capable to generate 9.3 nJ in 20 s from an actual rain event.

  7. The contribution of lakes to global inland fisheries harvest

    Science.gov (United States)

    Deines, Andrew M.; Bunnell, David B.; Rogers, Mark W.; Bennion, David; Woelmer, Whitney; Sayers, Michael J.; Grimm, Amanda G.; Shuchman, Robert A.; Raymer, Zachary B.; Brooks, Colin N.; Mychek-Londer, Justin G.; Taylor, William W.; Beard, Douglas

    2017-01-01

    Freshwater ecosystems provide numerous services for communities worldwide, including irrigation, hydropower, and municipal water; however, the services provided by inland fisheries – nourishment, employment, and recreational opportunities – are often comparatively undervalued. We provide an independent estimate of global lake harvest to improve biological and socioeconomic assessments of inland fisheries. On the basis of satellite-derived estimates of chlorophyll concentration from 80,012 globally distributed lakes, lake-specific fishing effort based on human population, and output from a Bayesian hierarchical model, we estimated that the global lake fishery harvest in the year 2011 was 8.4 million tons (mt). Our calculations excluded harvests from highly productive rivers, wetlands, and very small lakes; therefore, the true cumulative global fishery harvest from all freshwater sources likely exceeded 11 mt as reported by the Food and Agriculture Organization of the United Nations (FAO). This putative underestimate by the FAO could diminish the perceived importance of inland fisheries and perpetuate decisions that adversely affect these fisheries and millions of people.

  8. Study on Drive System of Hybrid Tree Harvester

    Directory of Open Access Journals (Sweden)

    Shen Rong-feng

    2017-01-01

    Full Text Available Hybrid tree harvester with a 60 kW diesel engine combined with a battery pile could be a “green” forest harvesting and transportation system. With the new design, the diesel engine maintains a constant engine speed, keeping fuel consumption low while charging the batteries that drive the forwarder. As an additional energy saving method, the electric motors work as generators to charge the battery pile when the vehicle moves downhill. The vehicle is equipped with six large wheels providing high clearance over uneven terrain while reducing ground pressure. Each wheel is driven via a hub gear by its own alternating current motor, and each of the three wheel pairs can be steered independently. The combination of the diesel engine and six electric motors provides plenty of power for heavy lifting and pulling. The main component parameters of the drive system are calculated and optimized with a set of dynamics and simulated with AVL Cruise software. The results provide practical insights for the fuel tree harvester and are helpful to reduce the structure and size of the tree harvester. Advantage Environment provides information about existing and future products designed to reduce environmental impacts.

  9. Systems for harvesting and handling cotton plant residue

    Energy Technology Data Exchange (ETDEWEB)

    Coates, W. [Univ. of Arizona, Tucson, AZ (United States)

    1993-12-31

    In the warmer regions of the United States, cotton plant residue must be buried to prevent it from serving as an overwintering site for insect pests such as the pink bollworm. Most of the field operations used to bury the residue are high energy consumers and tend to degrade soil structure, thereby increasing the potential for erosion. The residue is of little value as a soil amendment and consequently is considered a negative value biomass. A commercial system to harvest cotton plant residue would be of both economic and environmental benefit to cotton producers. Research has been underway at the University of Arizona since the spring of 1991 to develop a commercially viable system for harvesting cotton plant residue. Equipment durability, degree of densification, energy required, cleanliness of the harvested material, and ease of product handling and transport are some of the performance variables which have been measured. Two systems have proven superior. In both, the plants are pulled from the ground using an implement developed specifically for the purpose. In one system, the stalks are baled using a large round baler, while in the other the stalks are chopped with a forage harvester, and then made into packages using a cotton module maker. Field capacities, energy requirements, package density and durability, and ease of handling with commercially available equipment have been measured for both systems. Selection of an optimum system for a specific operation depends upon end use of the product, and upon equipment availability.

  10. Innovative thermal energy harvesting for future autonomous applications

    Science.gov (United States)

    Monfray, Stephane

    2013-12-01

    As communicating autonomous systems market is booming, the role of energy harvesting will be a key enabler. As example, heat is one of the most abundant energy sources that can be converted into electricity in order to power circuits. Harvesting systems that use wasted heat open new ways to power autonomous sensors when the energy consumption is low, or to create systems of power generators when the conversion efficiency is high. The combination of different technologies (low power μ-processors, μ-batteries, radio, sensors...) with new energy harvesters compatible with large varieties of use-cases with allow to address this booming market. Thanks to the conjunction of ultra-low power electronic development, 3D technologies & Systems in Package approaches, the integration of autonomous sensors and electronics with ambient energy harvesting will be achievable. The applications are very wide, from environment and industrial sensors to medical portable applications, and the Internet of things may also represent in the future a several billions units market.

  11. Innovative thermal energy harvesting for future autonomous applications

    International Nuclear Information System (INIS)

    Monfray, Stephane

    2013-01-01

    As communicating autonomous systems market is booming, the role of energy harvesting will be a key enabler. As example, heat is one of the most abundant energy sources that can be converted into electricity in order to power circuits. Harvesting systems that use wasted heat open new ways to power autonomous sensors when the energy consumption is low, or to create systems of power generators when the conversion efficiency is high. The combination of different technologies (low power μ-processors, μ-batteries, radio, sensors...) with new energy harvesters compatible with large varieties of use-cases with allow to address this booming market. Thanks to the conjunction of ultra-low power electronic development, 3D technologies and Systems in Package approaches, the integration of autonomous sensors and electronics with ambient energy harvesting will be achievable. The applications are very wide, from environment and industrial sensors to medical portable applications, and the Internet of things may also represent in the future a several billions units market

  12. Harvester : An edge service harvesting heterogeneous resources for ATLAS

    CERN Document Server

    Maeno, Tadashi; The ATLAS collaboration

    2018-01-01

    The Production and Distributed Analysis (PanDA) system has been successfully used in the ATLAS experiment as a data-driven workload management system. The PanDA system has proven to be capable of operating at the Large Hadron Collider data processing scale over the last decade including the Run 1 and Run 2 data taking periods. PanDA was originally designed to be weakly coupled with the WLCG processing resources. Lately the system is revealing the difficulties to optimally integrate and exploit new resource types such as HPC and preemptable cloud resources with instant spin-up, and new workflows such as the event service, because their intrinsic nature and requirements are quite different from that of traditional grid resources. Therefore, a new component, Harvester, has been developed to mediate the control and information flow between PanDA and the resources, in order to enable more intelligent workload management and dynamic resource provisioning based on detailed knowledge of resource capabilities and thei...

  13. Screen printed PZT/PZT thick film bimorph MEMS cantilever device for vibration energy harvesting

    DEFF Research Database (Denmark)

    Xu, Ruichao; Lei, Anders; Dahl-Petersen, Christian

    2012-01-01

    We present a microelectromechanical system (MEMS) based PZT/PZT thick film bimorph vibration energy harvester with an integrated silicon proof mass. Most piezoelectric energy harvesting devices use a cantilever beam of a non piezoelectric material as support beneath or in-between the piezoelectric...... elements. We show experimental results from two types PZT/PZT harvesting devices, one where the Pb(ZrxTi1−x)O3 (PZT) thick films are high pressure treated during the fabrication and the other where the treatment is omitted. We find that with the high pressure treatment prior to PZT sintering, the films...

  14. Wireless Energy Harvesting Using Signals from Multiple Fading Channels

    KAUST Repository

    Chen, Yunfei; Zhao, Nan; Alouini, Mohamed-Slim

    2017-01-01

    fading or Gamma-shadowed Rician fading. The received signals are then harvested by using either a single harvester for simultaneous transmissions or multiple harvesters for transmissions at different frequencies, antennas or time slots. Both linear

  15. The effects of harvest on waterfowl populations

    Science.gov (United States)

    Cooch, Evan G.; Guillemain, Matthieu; Boomer, G Scott; Lebreton, Jean-Dominique; Nichols, James D.

    2014-01-01

    Change in the size of populations over space and time is, arguably, the motivation for much of pure and applied ecological research. The fundamental model for the dynamics of any population is straightforward: the net change in the abundance is the simple difference between the number of individuals entering the population and the number leaving the population, either or both of which may change in response to factors intrinsic and extrinsic to the population. While harvest of individuals from a population constitutes a clear extrinsic source of removal of individuals, the response of populations to harvest is frequently complex, reflecting an interaction of harvest with one or more population processes. Here we consider the role of these interactions, and factors influencing them, on the effective harvest management of waterfowl populations. We review historical ideas concerning harvest and discuss the relationship(s) between waterfowl life histories and the development and application of population models to inform harvest management. The influence of population structure (age, spatial) on derivation of optimal harvest strategies (with and without explicit consideration of various sources of uncertainty) is considered. In addition to population structure, we discuss how the optimal harvest strategy may be influenced by: 1) patterns of density-dependence in one or more vital rates, and 2) heterogeneity in vital rates among individuals within an age-sex-size class. Although derivation of the optimal harvest strategy for simple population models (with or without structure) is generally straightforward, there are several potential difficulties in application. In particular, uncertainty concerning the population structure at the time of harvest, and the ability to regulate the structure of the harvest itself, are significant complications. We therefore review the evidence of effects of harvest on waterfowl populations. Some of this evidence has

  16. Optimization of passive low power wireless electromagnetic energy harvesters.

    Science.gov (United States)

    Nimo, Antwi; Grgić, Dario; Reindl, Leonhard M

    2012-10-11

    This work presents the optimization of antenna captured low power radio frequency (RF) to direct current (DC) power converters using Schottky diodes for powering remote wireless sensors. Linearized models using scattering parameters show that an antenna and a matched diode rectifier can be described as a form of coupled resonator with different individual resonator properties. The analytical models show that the maximum voltage gain of the coupled resonators is mainly related to the antenna, diode and load (remote sensor) resistances at matched conditions or resonance. The analytical models were verified with experimental results. Different passive wireless RF power harvesters offering high selectivity, broadband response and high voltage sensitivity are presented. Measured results show that with an optimal resistance of antenna and diode, it is possible to achieve high RF to DC voltage sensitivity of 0.5 V and efficiency of 20% at -30 dBm antenna input power. Additionally, a wireless harvester (rectenna) is built and tested for receiving range performance.

  17. Effect of harvest time on storage loss and sprouting in onion

    Directory of Open Access Journals (Sweden)

    T. SUOJALA

    2008-12-01

    Full Text Available Storability of onion is affected by timing of harvest. However, the optimal time for maximum yield and maximum storability do not necessarily coincide. This study aimed to determine the most suitable harvest time for obtaining a high bulb yield with high quality and storability. Storage experiments were conducted on onions produced in field experiments at a research field and on farms in four years. Results indicate that harvesting could be delayed to 100% maturity, or even longer, without a marked increase in storage loss. In rainy years, late harvest is likely to impair the quality. The incidence of sprouting in shelf life tests varied considerably between years. An early harvest before 50% maturity and a delayed harvest increased the risk of sprouting. It may be concluded that the harvesting of onions for long-term storage can be timed to take place between 50% maturity and even some weeks after complete maturity without a loss in storage quality. Therefore, it is possible to combine high yield and good storage quality.

  18. Energy harvesting from organic liquids in micro-sized microbial fuel cells

    KAUST Repository

    Mink, J.E.; Qaisi, R.M.; Logan, B.E.; Hussain, Muhammad Mustafa

    2014-01-01

    Micro-sized microbial fuel cells (MFCs) are miniature energy harvesters that use bacteria to convert biomass from liquids into usable power. The key challenge is transitioning laboratory test beds into devices capable of producing high power using

  19. A Self-Biased Active Voltage Doubler for Energy Harvesting Systems

    KAUST Repository

    Tayyab, Umais; Alzaher, Hussain A.

    2017-01-01

    An active voltage doubler utilizing a single supply op-amp for energy harvesting system is presented. The proposed doubler is used for rectification process to achieve both acceptably high power conversion efficiency (PCE) and large rectified DC

  20. Resource Allocation for Outdoor Visible Light Communications with Energy Harvesting Capabilities

    KAUST Repository

    Abdelhady, Amr Mohamed Abdelaziz; Amin, Osama; Chaaban, Anas; Alouini, Mohamed-Slim

    2018-01-01

    Visible light communication (VLC) is a promising technology that can support high data rate services for outdoor mass gathering night events while permitting energy harvesting. In this paper, a VLC system is considered where a transmitter sends data

  1. Piezoelectric energy harvesting for powering low power electronics

    Energy Technology Data Exchange (ETDEWEB)

    Leinonen, M.; Palosaari, J.; Hannu, J.; Juuti, J.; Jantunen, H. (Univ. of Oulu, Dept. of Electrical and Information Engineering (Finland)). email: jajuu@ee.oulu.fi

    2009-07-01

    vehicle traffic and used for e.g. road lightning. In direct piezoelectric effect stress or strain applied for the piezoelectric material generates a charge on the electroded faces of the component. In vibration based harvesters deformation is produced by vibrating mass of the piezoelement itself or external mass or directly transferring deformation of external system into piezoelectric material. The natural stiffness or Young's modulus of the piezoelectric material is relatively high (typically 50-70 GPa) and therefore vibration cannot normally generate required stresses for the material. In order to overcome this problem bending type structures are typically utilised in vibration based harvesters providing extremely compact internal leverage mechanism for the force amplification. One of the commonly used structures is a unimorph type cantilever which was chosen for this research. The component consists of active PZT and passive steel layers where the steel can be substituted with different materials such as post-processed ceramics to enable e.g. embedded and encapsulated structures. In this structure external mass is usually placed at the tip of the cantilever, in order to tune the resonance frequency and to enhance the coupling of the vibration for the piezoelectric material. Schematics of the complete energy harvesting system consists the energy harvester components and required electronics. The electronics in its simplest form can be a one stage design with a rectifier and the storage capacitor or it can have several stages with switched mode regulators providing controlled output voltage and high voltage energy storage significantly improving efficiency of the harvesting

  2. Bundling harvester; Harvennuspuun automaattisen nippukorjausharvesterin kehittaeminen

    Energy Technology Data Exchange (ETDEWEB)

    Koponen, K [Eko-Log Oy, Kuopio (Finland)

    1997-12-01

    The starting point of the project was to design and construct, by taking the silvicultural point of view into account, a harvesting and processing system especially for energy-wood, containing manually driven bundling harvester, automating of the harvester, and automated loading. The equipment forms an ideal method for entrepreneur`s-line harvesting. The target is to apply the system also for owner`s-line harvesting. The profitability of the system promotes the utilisation of the system in both cases. The objectives of the project were: to construct a test equipment and prototypes for all the project stages, to carry out terrain and strain tests in order to examine the usability and durability, as well as the capacity of the machine, to test the applicability of the Eko-Log system in simultaneous harvesting of energy and pulp woods, and to start the marketing and manufacturing of the products. The basic problems of the construction of the bundling harvester have been solved using terrain-tests. The prototype machine has been shown to be operable. Loading of the bundles to form sufficiently economically transportable loads has been studied, and simultaneously, the branch-biomass has been tried to be utilised without loosing the profitability of transportation. The results have been promising, and will promote the profitable utilisation of wood-energy. (orig.)

  3. Optical Sensing of Weed Infestations at Harvest.

    Science.gov (United States)

    Barroso, Judit; McCallum, John; Long, Dan

    2017-10-19

    Kochia ( Kochia scoparia L.), Russian thistle ( Salsola tragus L.), and prickly lettuce ( Lactuca serriola L.) are economically important weeds infesting dryland wheat ( Triticum aestivum L.) production systems in the western United States. Those weeds produce most of their seeds post-harvest. The objectives of this study were to determine the ability of an optical sensor, installed for on-the-go measurement of grain protein concentration, to detect the presence of green plant matter in flowing grain and assess the potential usefulness of this information for mapping weeds at harvest. Spectra of the grain stream were recorded continuously at a rate of 0.33 Hz during harvest of two spring wheat fields of 1.9 and 5.4 ha. All readings were georeferenced using a Global Positioning System (GPS) receiver with 1 m positional accuracy. Chlorophyll of green plant matter was detectable in the red (638-710 nm) waveband. Maps of the chlorophyll signal from both fields showed an overall agreement of 78.1% with reference maps, one constructed prior to harvest and the other at harvest time, both based on visual evaluations of the three green weed species conducted by experts. Information on weed distributions at harvest may be useful for controlling post-harvest using variable rate technology for herbicide applications.

  4. Simultaneous harvesting of straw and chaff for energy purposes : influence on bale density, yield, field drying process and combustion characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Lundin, G. [JTI Swedish Inst. of Agricultural and Environmental Engineering, Uppsala (Sweden); Ronnback, M. [SP Technical Research Inst. of Sweden, Boras (Sweden)

    2010-07-01

    The potential to increase the productivity of fuel straw harvest and transportation was examined. When harvesting straw for energy purposes, only the long fraction is currently collected. However, technological improvements have now rendered it possible to harvest chaff, thus increasing the amount of harvest residues and bale density. The purpose of this study was to determine how harvest yield, bale density, field-drying behaviour and combustion characteristics are affected by the simultaneous harvest of straw and chaff. Field experiments were conducted in 2009 for long- and short-stalked winter wheat crops. Combine harvesting was carried out with 2 different types of combine harvesters. A high-density baler was used to bale the crop residues. Mixing chaff in with the straw swath by combine harvesting gave a lower initial moisture content compared with straw only. The density and the weight of each bale were not affected by the treatments. However, the added chaff increased the total yield of crop residues by 14 per cent, indicating that about half of the biologically available chaff was harvested. Although mixing in chaff increased the ash content by 1 percentage unit, there was no considerable change in net calorific value or ash melting behaviour.

  5. Studies on optimum harvest time for hybrid rice seed.

    Science.gov (United States)

    Fu, Hong; Cao, Dong-Dong; Hu, Wei-Min; Guan, Ya-Jing; Fu, Yu-Ying; Fang, Yong-Feng; Hu, Jin

    2017-03-01

    Timely harvest is critical for hybrid rice to achieve maximum seed viability, vigor and yield. However, how to predict the optimum harvest time has been rarely reported so far. The seed vigor of Zhuliangyou 06 (ZLY06) increased and reached the highest level at 20 days after pollination (DAP), when seed moisture content had a lower value, which was maintained until final seed maturation. For Chunyou 84 (CY84), seed vigor, fresh and dry weight had relatively high values at 25 DAP, when seed moisture content reached the lowest value and changed slightly from 25 to 55 DAP. In both hybrid rice varieties, seed glume chlorophyll content declined rapidly from 10 to 30 DAP and remained at a very low level after 35 DAP. Starch content exhibited an increasing trend during seed maturation, while both soluble sugar content and amylase activity decreased significantly at the early stages of seed development. Moreover, correlation analyses showed that seed dry weight, starch content and superoxide dismutase activity were significantly positively correlated with seed vigor. In contrast, chlorophyll content, moisture content, soluble sugar, soluble protein, abscisic acid, gibberellin content, electrical conductivity, catalase and ascorbate peroxidase activities were significantly negatively correlated with seed vigor. Physiological and biochemical parameters were obviously more closely related with seed vigor than with seed germinability during seed development. Seed vigor could be better used as a comprehensive factor to predict the optimum seed harvest time. It is suggested that for ZLY06 seeds could be harvested as early as 20 DAP, whereas for CY84 the earliest optimum harvest time was 25 DAP. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  6. Treatment of peat bogs harvested by deep digging technique

    International Nuclear Information System (INIS)

    Hoernsten, L.

    1992-06-01

    The aim of this study is to describe how peat bogs harvested by deep digging technique can be treated after harvesting has come to an end. The study points out treatment methods, how the treatments are carried out and to indicate the most appropriate method of harvest for optimum results. Costs and benefits are calculated for the methods involving cultivation. The knowledge gained from traditional peat harvesting technique indicate forestry, energy wood production and establishment of ponds as possible alternatives. Energy grass cultivation and establishments of game parks have not been tested. but are assumed to be viable on suitable sites. Establishment of duck ponds are also possible, even though conditions for these are better on firm ground. In this study spruce is estimated to produce 200 cubic meters during 105 year whilst pine produces 300 cubic meters. Calculations for pine and spruce estimate costs of respectively 17000 and 18000 SEK per hectare after 105 years. Energy wood production is estimated to be 11.6 tons dry matter per hectare and year which gives a net cost of 19000 SEK per hectare. Similarly energy grass cultivation results in an average annual harvest of 6.5 ton dry matter and a cost of 59000 SEK per hectare. If the results are applied to three specific cases, then forest cultivation and establishment of ponds are possible in all cases. Neither energy wood nor energy grass are appropriate in any of the three regions. At the particular site for this study all methods mentioned are possible. Depending on whether draining leads to a high or low water table, the most appropriate course would be the establishment of a pond respectively a game park of forest cultivation. (59 refs., 12 tabs., 4 figs.)

  7. Design, simulation, fabrication, and characterization of MEMS vibration energy harvesters

    Science.gov (United States)

    Oxaal, John

    Energy harvesting from ambient sources has been a longtime goal for microsystem engineers. The energy available from ambient sources is substantial and could be used to power wireless micro devices, making them fully autonomous. Self-powered wireless sensors could have many applications in for autonomous monitoring of residential, commercial, industrial, geological, or biological environments. Ambient vibrations are of particular interest for energy harvesting as they are ubiquitous and have ample kinetic energy. In this work a MEMS device for vibration energy harvesting using a variable capacitor structure is presented. The nonlinear electromechanical dynamics of a gap-closing type structure is experimentally studied. Important experimental considerations such as the importance of reducing off-axis vibration during testing, characterization methods, dust contamination, and the effect of grounding on parasitic capacitance are discussed. A comprehensive physics based model is developed and validated with two different microfabricated devices. To achieve maximal power, devices with high aspect ratio electrodes and a novel two-level stopper system are designed and fabricated. The maximum achieved power from the MEMS device when driven by sinusoidal vibrations was 3.38 muW. Vibrations from HVAC air ducts, which have a primary frequency of 65 Hz and amplitude of 155 mgrms, are targeted as the vibration source and devices are designed for maximal power harvesting potential at those conditions. Harvesting from the air ducts, the devices reached 118 nW of power. When normalized to the operating conditions, the best figure of merit of the devices tested was an order of magnitude above state-of-the-art of the devices (1.24E-6).

  8. Low-frequency electromagnetic iirradiation treatment of grain in harvester

    Directory of Open Access Journals (Sweden)

    E. V. Zhalnin

    2016-01-01

    Full Text Available Treatment of crop seeds by low-frequency electromagnetic field contributes to obtaining high and stable yields. After this treatment in a laboratory environment crop production can increase from 15 to 40 percent. To research an effect of magnetic field on a seed material in the field we developed technological design for a seeds treatment in a combine harvester «Enisey-1200 NМ». Three modules of low frequency electromagnetic waves source were mounted in the design of transporting working elements from the threshing apparatus to the grain tank for the impact they have on the moving of freshly threshed grain portion. Conditions of magnetization of seeds vere varied. Influence of modes of grain treatment at threshing of spring wheat in a harvester on the effectiveness of the stimulation vere researched. A comparative laboratory analysis of quality of grain, magnetic directly in the harvester, and 3 months after thrashing showed that the new technology allows to increase sowing qualities of grain. Electromagnetic irradiation of grain in a harvester increases the germination of seeds from 6 to 20 percent, germination energy about 30 percent, also raises the weight of the plant parts and more qualitatively clears seeds of a peel that promotes best storage. Regime of magnetization determines a germination ability and readiness og seeds. The most pronounced effect of the grain magnetization is observed under irradiation becomes apparent for more than 9 minutes. Irradiation of grain placed in the hopper of the combine is more effective. The optimum parameters of electromagnetic radiation is a frequency equaled to 16 Hz, the value of magnetic induction of 6 mT. We proposed to extend the technology field stimulation of seeds with low-frequency magnetic field in order to increase germination and yield of different crops. An application of the proposed design of the electromagnetic module for any model and size of modern types of grain and rice harvesters

  9. Development and implementation of a dustfree and efficient pneumatic harvesting method; Poelyttoemaen ja tehokkaan imukokoamismenetelmaen kehittaeminen ja kaeyttoeoenotto

    Energy Technology Data Exchange (ETDEWEB)

    Nurminen, T; Ruokolainen, O; Rytkoenen, P.; Saastamoinen, V. [Vapo Oy, Jyvaeskylae (Finland); Kallio, M.; Aalto, J.; Leinonen, A.; Mehto, M. [VTT Energy, Jyvaeskylae (Finland)

    1997-12-01

    The overall aim of the research work (1995 - 1998) is to develop dust separators of the pneumatic harvester, to eliminate dust emissions and to plan and implement a more efficient pneumatic harvesting method. New JIK-35/96 pneumatic harvesters equipped with four secondary separating cyclones (17 units) were taken into use in spring 1996. In addition, 15 JIK-35 pneumatic harvesters constructed earlier were modified dustfree. The mechanical strength of the harvesters was improved by after-installations and by changing the drive method during harvesting. JIK-35/96 pneumatic harvester (test unit) was developed further during summertime. The greatest modification was testing of three secondary cyclones with a larger diameter. Dust separation of the larger cyclones was poorer than that of cyclones with a smaller diameter. In test runs, the test unit collected peat about 10 % more than the other harvesters of JIK-35 type. The fuel consumption of the test unit was about a fifth higher than that of the conventional JIK-35 harvester (20 vs 25 l/h). The larger pneumatic harvester, a prototype of 45 m{sup 3}, operated as a whole as expected. Exhaust air from the settling chamber of the harvester, and dust distributed well to the four parallel cyclones. Problems were high power demand and low pressure in the harvesting bin compared to those of JIK-35/96. The peat harvesting efficiency of the prototype was less than 2 kg/s m(m = nozzle of 1 m width), while the corresponding value of JIK-35/96 ranged 2.5 - 4 kg/s m. In continuation, the aim is to eliminate problems of the prototype and to construct a more efficient version, i.e., by enlarging the width

  10. Energy harvesting “3-D knitted spacer” based piezoelectric textiles

    Science.gov (United States)

    Anand, S.; Soin, N.; Shah, T. H.; Siores, E.

    2016-07-01

    The piezoelectric effect in Poly(vinylidene fluoride), PVDF, was discovered over four decades ago and since then, significant work has been carried out aiming at the production of high p-phase fibres and their integration into fabric structures for energy harvesting. However, little work has been done in the area of production of “true piezoelectric fabric structures” based on flexible polymeric materials such as PVDF. In this work, we demonstrate “3-D knitted spacer” technology based all-fibre piezoelectric fabrics as power generators and energy harvesters. The knitted single-structure piezoelectric generator consists of high p-phase (~80%) piezoelectric PVDF monofilaments as the spacer yarn interconnected between silver (Ag) coated polyamide multifilament yarn layers acting as the top and bottom electrodes. The novel and unique textile structure provides an output power density in the range of 1.105.10 gWcm-2 at applied impact pressures in the range of 0.02-0.10 MPa, thus providing significantly higher power outputs and efficiencies over the existing 2-D woven and nonwoven piezoelectric structures. The high energy efficiency, mechanical durability and comfort of the soft, flexible and all-fibre based power generator is highly attractive for a variety of potential applications such as wearable electronic systems and energy harvesters charged from ambient environment or by human movement.

  11. Successful and unsuccessful attempts to resolve caribou management and timber harvesting issues in west central Alberta

    Directory of Open Access Journals (Sweden)

    David Hervieux

    1996-01-01

    Full Text Available Research studies of woodland caribou in west central Alberta began in 1979 in response to proposed timber harvesting on their winter ranges. Using results from initial studies, timber harvest guidelines were developed. A recent review of these guidelines, and the assumptions on which they were based, has resulted in a renegotiation by government and industry of timber harvesting on caribou range in west central Alberta. Caribou range in west central Alberta overlaps many jurisdictional boundaries: federal and provincial lands, four Forest Management Agreement Areas, three Alberta Land and Forest Service Regions and two Alberta Fish and Wildlife Service Regions. This jurisdictional complexity in combination with other factors such as total allocation of the timber resources, high levels of petroleum, natural gas and coal extraction activities, a high level of concern by public groups for caribou conservation and recent understanding of woodland caribou needs for abundant space has made resolution of caribou/timber harvest conflicts exceedingly slow and often relatively unproductive. This paper reviews 10 years of trying to resolve conflicts between timber harvesting and caribou conservation through meetings, committees, integrated resource planning, policy papers and public consultation. We describe what might be learned by other jurisdictions that are trying to resolve similar caribou/timber harvesting issues. We conclude with an overview of recent timber harvest planning initiatives on caribou range in west central Alberta.

  12. Climate Change Decouples Drought from Early Wine Grape Harvests in France

    Science.gov (United States)

    Cook, Benjamin I.; Wolkovich, Elizabeth M.

    2016-01-01

    Across the world, wine grape phenology has advanced in recent decades, in step with climate-change-induced trends in temperature - the main driver of fruit maturation - and drought. Fully understanding how climate change contributes to changes in harvest dates, however, requires analysing wine grape phenology and its relationship to climate over a longer-term context, including data predating anthropogenic interference in the climate system. Here, we investigate the climatic controls of wine grape harvest dates from 1600-2007 in France and Switzerland using historical harvest and climate data. Early harvests occur with warmer temperatures (minus 6 days per degree Centigrade) and are delayed by wet conditions (plus 0.07 days per millimeter; plus 1.68 days per PDSI (Palmer drought severity index)) during spring and summer. In recent decades (1981-2007), however, the relationship between harvest timing and drought has broken down. Historically, high summer temperatures in Western Europe, which would hasten fruit maturation, required drought conditions to generate extreme heat. The relationship between drought and temperature in this region, however, has weakened in recent decades and enhanced warming from anthropogenic greenhouse gases can generate the high temperatures needed for early harvests without drought. Our results suggest that climate change has fundamentally altered the climatic drivers of early wine grape harvests in France, with possible ramifications for viticulture management and wine quality.

  13. Application of Metamaterials to RF Energy Harvesting and Infrared Photodetection

    Science.gov (United States)

    Fowler, Clayton M.

    Techniques for adapting metamaterials for the improvement of RF energy harvesting and infrared photodetection are demonstrated using experimental and computer simulation methods. Two methods for RF energy harvesting are experimentally demonstrated and supported by computer simulation. In the first method, a metamaterial perfect absorber (MPA) is made into a rectenna capable of harvesting RF energy and delivering power to a load by soldering Schottky diodes onto connected split ring resonator (SRR) structures composing the planar metasurface of the perfect absorber. The metamaterial rectenna is accompanied by a ground plane placed parallel to it, which forms a Fabry-Perot cavity between the metasurface and the ground plane. The Fabry-Perot cavity stores energy in the form of standing waves which is transferred to the SRR structures of the metasurface as AC currents that are rectified by the diodes to create DC power. This type of design enables highly efficient energy harvesting for low input power, creates a large antenna capture area, and uses elements with small electrical size, such that 100 uW of power (enough to operate simple devices) can be captured at ambient intensities 1 - 2 uW/cm2. Two designs using this method are presented, one that operates for linear polarizations at 0.9 GHz and a smaller polarization-independent design that operates around 1.5 GHz. In the second method, the energy stored in the standing waves of an MPA Fabry-Perot cavity is instead harvested by placing a separate energy harvesting antenna within the cavity. The cavity shapes and enhances the incident electric field, and then the separate energy harvesting antenna is designed to be inserted into the cavity so that its shape and/or radiation pattern matches the electric field lines within the cavity and maximally extracts the stored energy. This method allows for great customization of antenna design parameters, such as operating frequency, polarization dependence, and directionality

  14. Conjugated Polymers for Flexible Energy Harvesting and Storage.

    Science.gov (United States)

    Zhang, Zhitao; Liao, Meng; Lou, Huiqing; Hu, Yajie; Sun, Xuemei; Peng, Huisheng

    2018-03-01

    Since the discovery of conjugated polymers in the 1970s, they have attracted considerable interest in light of their advantages of having a tunable bandgap, high electroactivity, high flexibility, and good processability compared to inorganic conducting materials. The above combined advantages make them promising for effective energy harvesting and storage, which have been widely studied in recent decades. Herein, the key advancements in the use of conjugated polymers for flexible energy harvesting and storage are reviewed. The synthesis, structure, and properties of conjugated polymers are first summarized. Then, their applications in flexible polymer solar cells, thermoelectric generators, supercapacitors, and lithium-ion batteries are described. The remaining challenges are then discussed to highlight the future direction in the development of conjugated polymers. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Harvest time and post-harvest quality of Fuyu persimmon treated before harvest with gibberellic acid and aminoetoxyvinilglycine

    Directory of Open Access Journals (Sweden)

    Ricardo Antonio Ayub

    2008-12-01

    Full Text Available The aim of this work was to evaluate the effects of gibberellic acid (GA3 and aminoetoxyvinilglycine (AVG applied in preharvest spraying, on the retardation of the harvest and on the quality of persimmon fruits cv. Fuyu. The experiment was carried in randomized complete block design. The treatments were: control, 136mgL-1 of AVG, 272 mgL-1 of AVG, 36mgL-1 of GA3, 72mgL-1 of GA3 and 136mgL-1 of AVG + 36mgL-1 of GA3, spraying 30 days before the first harvest. The fruits were harvested twice and stored at 4ºC. The chemical and physical evaluations of the fruits were carried out the date of the harvest and at intervals of 15 days followed by four days at 20ºC. In conclusion, the application of AVG (136mgL-1 or GA3 (72mgL-1 maintained the firmness of the fruits and delayed harvest by twenty days. However, fruits harvested in the initial state of ripening were more sensitive to chilling injury and were unable to support 15 days of storage at 4ºC. The plant growth regulators were not efficient in prolonged storage due to the fact that the concentration of sugars was lower in the treatments than in the control.

  16. Allometric analysis of the effects of density on reproductive allocation and Harvest Index in 6 varieties of wheat (Triticum)

    DEFF Research Database (Denmark)

    Qin, Xiao-liang; Weiner, Jacob; Qi, Lin

    2013-01-01

    allocation should be analyzed and interpreted allometrically because ratios or fractions such as Reproductive Effort or Harvest Index are size dependent. We investigated reproductive allocation of individuals in 6 varieties of Triticum (wheat) grown at a wide range of densities. We harvested leaves, stems...... size. There were significant differences among the varieties in the allometric exponent (slope of log–log relationship) of grain versus vegetative mass, such that some varieties produced higher yield (and therefore had a higher Harvest Index) than others when plants were small, while others had higher...... yield at larger sizes. Thus, the Harvest Index and its rank among varieties changed with plant size, which puts into question the practice of selecting for Harvest Index when crop performance varies greatly among individuals, years or environments. Selection for a high Harvest Index when individuals...

  17. Optically nonlinear energy transfer in light-harvesting dendrimers

    OpenAIRE

    Andrews, David; Bradshaw, DS

    2004-01-01

    Dendrimeric polymers are the subject of intense research activity geared towards their implementation in nanodevice applications such as energy harvesting systems,organic light-emitting diodes, photosensitizers, low-threshold lasers, and quantum logic elements, etc. A recent development in this area has been the construction of dendrimers specifically designed to exhibit novel forms of optical nonlinearity, exploiting the unique properties of these materials at high levels of photon flux. Sta...

  18. Adaptive learning algorithms for vibration energy harvesting

    International Nuclear Information System (INIS)

    Ward, John K; Behrens, Sam

    2008-01-01

    By scavenging energy from their local environment, portable electronic devices such as MEMS devices, mobile phones, radios and wireless sensors can achieve greater run times with potentially lower weight. Vibration energy harvesting is one such approach where energy from parasitic vibrations can be converted into electrical energy through the use of piezoelectric and electromagnetic transducers. Parasitic vibrations come from a range of sources such as human movement, wind, seismic forces and traffic. Existing approaches to vibration energy harvesting typically utilize a rectifier circuit, which is tuned to the resonant frequency of the harvesting structure and the dominant frequency of vibration. We have developed a novel approach to vibration energy harvesting, including adaptation to non-periodic vibrations so as to extract the maximum amount of vibration energy available. Experimental results of an experimental apparatus using an off-the-shelf transducer (i.e. speaker coil) show mechanical vibration to electrical energy conversion efficiencies of 27–34%

  19. Allogeneic Peripheral Blood Stem Cell Harvest

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Allogeneic Peripheral Blood Stem Cell Harvest. Mobilization protocol. G-CSF 10 mcg/Kg / day for 5 days. Pheresis. Cobe Spectra; Haemonetics mcs+. Enumeration. CD34 counts; Cfu-GM assays.

  20. Energy harvesting with functional materials and microsystems

    CERN Document Server

    Bhaskaran, Madhu; Iniewski, Krzysztof

    2013-01-01

    For decades, people have searched for ways to harvest energy from natural sources. Lately, a desire to address the issue of global warming and climate change has popularized solar or photovoltaic technology, while piezoelectric technology is being developed to power handheld devices without batteries, and thermoelectric technology is being explored to convert wasted heat, such as in automobile engine combustion, into electricity. Featuring contributions from international researchers in both academics and industry, Energy Harvesting with Functional Materials and Microsystems explains the growi

  1. Dust emissions eliminated in pneumatic harvesting

    International Nuclear Information System (INIS)

    Kallio, M.

    1998-01-01

    Pneumatic harvesting is the most efficient milled peat production method in unsteady weather conditions. In good summers, the best contractors harvest more than 1 000 m 3 /ha milled peat from suitable production fields. The greatest problem of the method is caused by dust emissions, in particular in fields close to settled areas. About 15 % of Finland's present peat production is collected using pneumatic harvesters. A pneumatic harvester with smaller dust emissions has been developed by VTT Energy and Vapo Oy. The wagon is based on two-stage separation of peat. The main part of the coarser milled peat is first separated, e.g. in a settling chamber, and fine dry peat dust in correctly dimensioned side by side cyclones. The first series of pneumatic harvesters based on the new separation technology was employed in summer 1996. Besides decreasing the dust emissions the harvesting capacity of the new equipment was increased. The collection capacity of the pneumatic harvester can be made more effective by enlarging the container size, be decreasing the weight, by increasing the driving speed and by developing the suction capacity. Using lighter and durable construction materials combined with advanced design lighter and stronger pneumatic harvesters have been constructed. Nozzles and their mounting have also been developed. In the improvement of nozzles, the former studies with pneumatic simulator of VTT Energy, have been of great help. Studies with the pneumatic simulator and field conditions have been made in collaboration with Turveruukki Oy, Turvemetalli Oy, Raussin Metalli Oy and Vapo Oy, as well as VNIITP of St. Petersburg, Russia

  2. HYBRID POWER HARVESTER USING ENGINE SOURCE

    OpenAIRE

    Meeran Mydeen, A.Ahmed; Inasu, Kelwin; Venkatesh, M.; Suthesh, C.

    2017-01-01

    In mainly we present a compact, multisource and battery-free energy harvesting from engine source. This battery free generator captures energy from its environment transient thermal gradients as a main source, and vibration as a secondary source allowing early biasing of the generator and stores this energy in ultra-capacitors .In this way, this multi-source architecture benefits from the synergy between energy scavenging and harvesting.

  3. Autotransplantation donor tooth site harvesting using piezosurgery

    OpenAIRE

    Ylikontiola, Leena P.; S?ndor, George K.

    2016-01-01

    Abstract Background: The harvesting of a tooth as a candidate for tooth autotransplantation requires that the delicate dental tissues around the tooth be minimally traumatized. This is especially so for the periradicular tissues of the tooth root and the follicular tissues surrounding the crown. The aim of this report is to describe the use of piezosurgery as an attempt at morbidity reduction in the harvesting of teeth for autotransplantation. Methods: A piezosurgical handpiece and its ...

  4. Dielectric loss against piezoelectric power harvesting

    International Nuclear Information System (INIS)

    Liang, Junrui; Shu-Hung Chung, Henry; Liao, Wei-Hsin

    2014-01-01

    Piezoelectricity is one of the most popular electromechanical transduction mechanisms for constructing kinetic energy harvesting systems. When a standard energy harvesting (SEH) interface circuit, i.e., bridge rectifier plus filter capacitor, is utilized for collecting piezoelectric power, the previous literature showed that the power conversion can be well predicted without much consideration for the effect of dielectric loss. Yet, as the conversion power gets higher by adopting power-boosting interface circuits, such as synchronized switch harvesting on inductor (SSHI), the neglect of dielectric loss might give rise to deviation in harvested power estimation. Given the continuous progress on power-boosting interface circuits, the role of dielectric loss in practical piezoelectric energy harvesting (PEH) systems should receive attention with better evaluation. Based on the integrated equivalent impedance network model, this fast track communication provides a comprehensive study on the susceptibility of harvested power in PEH systems under different conditions. It shows that, dielectric loss always counteracts piezoelectric power harvesting by causing charge leakage across piezoelectric capacitance. In particular, taking corresponding ideal lossless cases as references, the counteractive effect might be aggravated under one of the five conditions: larger dielectric loss tangent, lower vibration frequency, further away from resonance, weaker electromechanical coupling, or using power-boosting interface circuit. These relationships are valuable for the study of PEH systems, as they not only help explain the role of dielectric loss in piezoelectric power harvesting, but also add complementary insights for material, structure, excitation, and circuit considerations towards holistic evaluation and design for practical PEH systems. (fast track communications)

  5. Mechanised harvesting of short-rotation coppices

    OpenAIRE

    Vanbeveren, Stefan P.P.; Spinelli, Raffaele; Eisenbies, Mark; Schweier, Janine; Mola-Yudego, Blas; Magagnotti, Natascia; Acuna, Mauricio; Dimitriou, Ioannis; Ceulemans, Reinhart

    2017-01-01

    Abstract: Short-rotation coppice (SRC) is an important source of woody biomass for bioenergy. Despite the research carried out on several aspects of SRC production, many uncertainties create barriers to farmers establishing SRC plantations. One of the key economic sources of uncertainty is harvesting methods and costs; more specifically, the performance of contemporary machine methods is reviewed. We collected data from 25 literature references, describing 166 field trials. Three harvesting s...

  6. The effect of roofing material on the quality of harvested rainwater.

    Science.gov (United States)

    Mendez, Carolina B; Klenzendorf, J Brandon; Afshar, Brigit R; Simmons, Mark T; Barrett, Michael E; Kinney, Kerry A; Kirisits, Mary Jo

    2011-02-01

    Due to decreases in the availability and quality of traditional water resources, harvested rainwater is increasingly used for potable and non-potable purposes. In this study, we examined the effect of conventional roofing materials (i.e., asphalt fiberglass shingle, Galvalume(®) metal, and concrete tile) and alternative roofing materials (i.e., cool and green) on the quality of harvested rainwater. Results from pilot-scale and full-scale roofs demonstrated that rainwater harvested from any of these roofing materials would require treatment if the consumer wanted to meet United States Environmental Protection Agency primary and secondary drinking water standards or non-potable water reuse guidelines; at a minimum, first-flush diversion, filtration, and disinfection are recommended. Metal roofs are commonly recommended for rainwater harvesting applications, and this study showed that rainwater harvested from metal roofs tends to have lower concentrations of fecal indicator bacteria as compared to other roofing materials. However, concrete tile and cool roofs produced harvested rainwater quality similar to that from the metal roofs, indicating that these roofing materials also are suitable for rainwater harvesting applications. Although the shingle and green roofs produced water quality comparable in many respects to that from the other roofing materials, their dissolved organic carbon concentrations were very high (approximately one order of magnitude higher than what is typical for a finished drinking water in the United States), which might lead to high concentrations of disinfection byproducts after chlorination. Furthermore the concentrations of some metals (e.g., arsenic) in rainwater harvested from the green roof suggest that the quality of commercial growing media should be carefully examined if the harvested rainwater is being considered for domestic use. Hence, roofing material is an important consideration when designing a rainwater catchment. Copyright

  7. Site quality influence over understory plant diversity in old-growth and harvested Nothofagus pumilio forests

    Directory of Open Access Journals (Sweden)

    E. A. Gallo

    2013-04-01

    Full Text Available Aim of study: The effects and interactions of shelterwood forest harvesting and site qualities over understory plant species diversity and composition were compared among primary and harvested Nothofagus pumilio forests.Area of study: Tierra del Fuego (Argentina, on three pure conditions (one and six year-old harvested, and primary without previous harvesting forests and three site qualities (high, medium and low.Material and Methods: Understory richness and cover (% were registered in five replicates of 1 hectare each per treatment. Taxonomic species were classified in categories (groups, origin and life forms. Two-way ANOVAs and multivariate analyses were conducted.Main results: Shelterwood harvesting and site quality significantly influenced understory cover and richness, which allow the introduction of native and exotic species and increasing of dicot and monocot covers. In dicots, monocots, exotics and total groups, higher richness and covers were related to time. Meanwhile, cover reached similar high values in all site qualities on dicot, native and total groups. On the other hand, monocot and exotic richness and cover remain similar in primary and recently harvested forests, and greatly increased in old harvested forests. Mosses and ferns were among the most sensitive groups.Research highlights: Impacts of shelterwood cut depend on site quality of the stands and time since harvesting occurs. For this, different site quality stands should received differential attention in the development of conservation strategies, as well as variations in the shelterwood implementation (as irregularity and patchiness should be considered to better promote understory plant species conservation inside managed areas.Key words: plant species conservation; years after harvesting; forest management; Tierra del Fuego.

  8. Variability after 15 Years of Vegetation Recovery in Natural Secondary Forest with Timber Harvesting at Different Intensities in Southeastern China: Community Diversity and Stability

    Directory of Open Access Journals (Sweden)

    Zhilong Wu

    2018-01-01

    Full Text Available The mixed Cunninghamia lanceolata (Lamb. Hook., Pinus massoniana Lamb., and hardwood forest in southeastern China is a major assemblage in natural secondary forests, and of national and international importance in terms of both timber and ecosystem services. However, over-harvesting has threatened its long-term sustainability, and there is a knowledge gap relating to the effect of harvesting on the ecosystem. After conifer species were selected for harvesting, the mixed Chinese fir, pine, and hardwood forest was changed into mixed evergreen broadleaf forest. In this context, we observed the restoration dynamics of plant communities over a period of 15 years (1996 to 2011 with different levels of harvesting intensity, including selective harvesting at low (13.0% removal of growing stock volume, medium (29.1%, high (45.8%, and extra-high (67.1% intensities, as well as clear-cut harvesting (100.0%, with non-harvesting as the control, based on permanent sample plots established in a randomized block design in these forests in southeastern China. The impact on the richness, diversity, and evenness of plant species derived from descriptive statistical analyses was shown to initially increase, and then decrease, with an increase in harvesting intensity. The most critical impacts were on the richness, diversity, and evenness of shrub and herb species. Richness, diversity, and evenness of plant species recovered and increased under selective harvesting at low and medium intensities, while these parameters had not recovered and significantly decreased under selective harvesting at high and extra-high intensities, as well as with clear-cut harvesting. The impact on the plant community stability was derived from the stability test method of the improved Godron M. The plant community stability was closest to the point of stability (20/80 under selective harvesting at medium intensity, followed by selective harvesting at low intensity. The plant community

  9. Improving Vibration Energy Harvesting Using Dynamic Magnifier

    Directory of Open Access Journals (Sweden)

    Almuatasim Alomari

    2016-01-01

    Full Text Available This paper reports on the design and evaluation of vibration-based piezoelectric energy-harvesting devices based on a polyvinylidene fluoride unimorph cantilever beam attached to the front of a dynamic magnifier. Experimental studies of the electromechanical frequency response functions are studied for the first three resonance frequencies. An analytical analysis is undertaken by applying the chain matrix in order to predict output voltage and output power with respect to the vibration frequency. The proposed harvester was modeled using MATLAB software and COMSOL multi- physics to study the mode shapes and electrical output parameters. The voltage and power output of the energy harvester with a dynamic magnifier was 2.62 V and 13.68 mW, respectively at the resonance frequency of the second mode. The modeling approach provides a basis to design energy harvesters exploiting dynamic magnification for improved performance and bandwidth. The potential application of such energy harvesting devices in the transport sector include autonomous structural health monitoring systems that often include embedded sensors, data acquisition, wireless communication, and energy harvesting systems.

  10. Vibration energy harvesting using the Halbach array

    International Nuclear Information System (INIS)

    Zhu, Dibin; Beeby, Steve; Tudor, John; Harris, Nick

    2012-01-01

    This paper studies the feasibility of vibration energy harvesting using a Halbach array. A Halbach array is a specific arrangement of permanent magnets that concentrates the magnetic field on one side of the array while cancelling the field to almost zero on the other side. This arrangement can improve electromagnetic coupling in a limited space. The Halbach array offers an advantage over conventional layouts of magnets in terms of its concentrated magnetic field and low-profile structure, which helps improve the output power of electromagnetic energy harvesters while minimizing their size. Another benefit of the Halbach array is that due to the existence of an almost-zero magnetic field zone, electronic components can be placed close to the energy harvester without any chance of interference, which can potentially reduce the overall size of a self-powered device. The first reported example of a low-profile, planar electromagnetic vibration energy harvester utilizing a Halbach array was built and tested. Results were compared to ones for energy harvesters with conventional magnet layouts. By comparison, it is concluded that although energy harvesters with a Halbach array can have higher magnetic field density, a higher output power requires careful design in order to achieve the maximum magnetic flux gradient. (paper)

  11. Freeze cast porous barium titanate for enhanced piezoelectric energy harvesting

    Science.gov (United States)

    Roscow, J. I.; Zhang, Y.; Kraśny, M. J.; Lewis, R. W. C.; Taylor, J.; Bowen, C. R.

    2018-06-01

    Energy harvesting is an important developing technology for a new generation of self-powered sensor networks. This paper demonstrates the significant improvement in the piezoelectric energy harvesting performance of barium titanate by forming highly aligned porosity using freeze casting. Firstly, a finite element model demonstrating the effect of pore morphology and angle with respect to poling field on the poling behaviour of porous ferroelectrics was developed. A second model was then developed to understand the influence of microstructure-property relationships on the poling behaviour of porous freeze cast ferroelectric materials and their resultant piezoelectric and energy harvesting properties. To compare with model predictions, porous barium titanate was fabricated using freeze casting to form highly aligned microstructures with excellent longitudinal piezoelectric strain coefficients, d 33. The freeze cast barium titanate with 45 vol.% porosity had a d 33  =  134.5 pC N‑1 compared to d 33  =  144.5 pC N‑1 for dense barium titanate. The d 33 coefficients of the freeze cast materials were also higher than materials with uniformly distributed spherical porosity due to improved poling of the aligned microstructures, as predicted by the models. Both model and experimental data indicated that introducing porosity provides a large reduction in the permittivity () of barium titanate, which leads to a substantial increase in energy harvesting figure of merit, , with a maximum of 3.79 pm2 N‑1 for barium titanate with 45 vol.% porosity, compared to only 1.40 pm2 N‑1 for dense barium titanate. Dense and porous barium titanate materials were then used to harvest energy from a mechanical excitation by rectification and storage of the piezoelectric charge on a capacitor. The porous barium titanate charged the capacitor to a voltage of 234 mV compared to 96 mV for the dense material, indicating a 2.4-fold increase that was similar to that

  12. Engineering, nutrient removal, and feedstock conversion evaluations of four corn stover harvest scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Hoskinson, Reed L.; Radtke, Corey W. [Idaho National Laboratory, P.O Box 1625, Idaho Falls, ID 83415-2210 (United States); Karlen, Douglas L. [USDA-ARS, National Soil Tilth Laboratory, Ames, IA 50011-3120 (United States); Birrell, Stuart J. [Iowa State University, Agricultural and Biosystems Engineering Department, Ames, IA 50011 (United States); Wilhelm, W.W. [USDA-ARS, Soil and Water Conservation Research Unit, Lincoln, NE 68583-0934 (United States)

    2007-02-15

    Crop residue has been identified as a near-term source of biomass for renewable fuel, heat, power, chemicals and other bio-materials. A prototype one-pass harvest system was used to collect residue samples from a corn (Zea mays L.) field near Ames, IA. Four harvest scenarios (low cut, high-cut top, high-cut bottom, and normal cut) were evaluated and are expressed as collected stover harvest indices (CSHI). High-cut top and high-cut bottom samples were obtained from the same plot in separate operations. Chemical composition, dilute acid pretreatment response, ethanol conversion yield and efficiency, and thermochemical conversion for each scenario were determined. Mean grain yield in this study (10.1 Mg ha{sup -1} dry weight) was representative of the average yield (10.0 Mg ha{sup -1}) for the area (Story County, IA) and year (2005). The four harvest scenarios removed 6.7, 4.9, 1.7, and 5.1 Mg ha{sup -1} of dry matter, respectively, or 0.60 for low cut, 0.66 for normal cut, and 0.61 for the total high-cut (top+bottom) scenarios when expressed as CSHI values. The macro-nutrient replacement value for the normal harvest scenario was $57.36 ha{sup -1} or $11.27 Mg{sup -1}. Harvesting stalk bottoms increased stover water content, risk of combine damage, estimated transportation costs, and left insufficient soil cover, while also producing a problematic feedstock. These preliminary results indicate harvesting stover (including the cobs) at a height of approximately 40 cm would be best for farmers and ethanol producers because of faster harvest speed and higher quality ethanol feedstock. (author)

  13. Microfabrication and Integration of a Sol-Gel PZT Folded Spring Energy Harvester

    Directory of Open Access Journals (Sweden)

    Jonathan Lueke

    2015-05-01

    Full Text Available This paper presents the methodology and challenges experienced in the microfabrication, packaging, and integration of a fixed-fixed folded spring piezoelectric energy harvester. A variety of challenges were overcome in the fabrication of the energy harvesters, such as the diagnosis and rectification of sol-gel PZT film quality and adhesion issues. A packaging and integration methodology was developed to allow for the characterizing the harvesters under a base vibration. The conditioning circuitry developed allowed for a complete energy harvesting system, consisting a harvester, a voltage doubler, a voltage regulator and a NiMH battery. A feasibility study was undertaken with the designed conditioning circuitry to determine the effect of the input parameters on the overall performance of the circuit. It was found that the maximum efficiency does not correlate to the maximum charging current supplied to the battery. The efficiency and charging current must be balanced to achieve a high output and a reasonable output current. The development of the complete energy harvesting system allows for the direct integration of the energy harvesting technology into existing power management schemes for wireless sensing.

  14. Short communication. Harvest time in hedgerow Arbequina olive orchards in areas with early frosts

    Energy Technology Data Exchange (ETDEWEB)

    Gracia, P.; Sanchez-Gimeno, A. C.; Benito, M.; Oria, R.; Lasa, J. M.

    2012-11-01

    The shortening of harvest time attained in hedgerow olive (Olea europaea L.) orchards represents an advantage for the adoption of this cropping system in areas that are prone to suffer frost during the harvest period. To establish an optimal harvesting window, we carried out a study of the fruit ripening process on a hedgerow orchard of Arbequina olive trees, located in Zaragoza (Spain). From 2007 to 2009, oil accumulation on the fruit (% of dry weight) and oil yield (grams of oil per 100 fruits) were monitored, from early September to late November. Over the three years both variables peaked around November 15th, indicating that Arbequina reached full ripening earlier than has been reported previously for this variety. In two of the three seasons the orchard suffered several frosts during November. Long term climatic data from this area indicated that the risk of early frosts (< -2 degree centigrade) increases as November progresses with a high risk after November 20{sup t}h. In conclusion, the optimal harvesting period for Arbequina in this area should not extend beyond November 20{sup t}h. A rapid harvesting before this date is advisable to avoid the risk of damage caused by early frost in Zaragoza. Hedgerow planting provides an additional advantage in frost-prone areas, because mechanization of operations permits a short harvest period, easier to fit into the optimal harvesting window. (Author) 20 refs.

  15. Microfabrication and integration of a sol-gel PZT folded spring energy harvester.

    Science.gov (United States)

    Lueke, Jonathan; Badr, Ahmed; Lou, Edmond; Moussa, Walied A

    2015-05-26

    This paper presents the methodology and challenges experienced in the microfabrication, packaging, and integration of a fixed-fixed folded spring piezoelectric energy harvester. A variety of challenges were overcome in the fabrication of the energy harvesters, such as the diagnosis and rectification of sol-gel PZT film quality and adhesion issues. A packaging and integration methodology was developed to allow for the characterizing the harvesters under a base vibration. The conditioning circuitry developed allowed for a complete energy harvesting system, consisting a harvester, a voltage doubler, a voltage regulator and a NiMH battery. A feasibility study was undertaken with the designed conditioning circuitry to determine the effect of the input parameters on the overall performance of the circuit. It was found that the maximum efficiency does not correlate to the maximum charging current supplied to the battery. The efficiency and charging current must be balanced to achieve a high output and a reasonable output current. The development of the complete energy harvesting system allows for the direct integration of the energy harvesting technology into existing power management schemes for wireless sensing.

  16. Recovery following experimental harvesting of Laminaria longicruris and L. digitata in southwestern Nova Scotia

    Energy Technology Data Exchange (ETDEWEB)

    Smith, B D

    1985-01-01

    Laminaria population variables and understory community composition were monitored just prior to, and for two summers following, a September 1980 experimental total harvest of L. longicruris De la Pylaie and L. digitata (L.) Lamouroux within two plots in Lobster Bay, Nova Scotia. Both plots, distinguished mainly by depth, were characterized by high Laminaria standing crop and no recent history of extensive sea urchin grazing. Within the shallower plot (2-3 m below MSL), recovery could not be assessed thoroughly due to ice damage, but within the deeper plot (3-4 m below MSL), L. longicruris regrew cropped biomass and attained maximum observed abundance within one year. Both Laminaria species required two years to mature to pre-harvest population characteristics. Survivorship of 0-1 year old and mature populations of both species was generally low (0-67% per year); however, the higher maximum life expectancy of L. digitata (>4 years vs 2 years) can result in that species persisting to the disadvantage of L. longicruris. Analysis of understory community composition for both harvested plots and their adjacent controls weakly distinguished the harvested plots one summer after harvesting from all others. It is doubtful the distinction is attributable to harvesting and in neither site was there evidence of a critical change in the understory community. Management implications for the commercial harvest of the brown alga Laminaria are discussed.

  17. Effect of Harvesting Stage on Sweet Sorghum (Sorghum bicolor L. Genotypes in Western Kenya

    Directory of Open Access Journals (Sweden)

    Moses Owuor Oyier

    2017-01-01

    Full Text Available Harvesting stage of sweet sorghum (Sorghum bicolor L. Moench cane is an important aspect in the content of sugar for production of industrial alcohol. Four sweet sorghum genotypes were evaluated for harvesting stage in a randomized complete block design. In order to determine sorghum harvest growth stage for bioethanol production, sorghum canes were harvested at intervals of seven days after anthesis. The genotypes were evaluated at different stages of development for maximum production of bioethanol from flowering to physiological maturity. The canes were crushed and juice fermented to produce ethanol. Measurements of chlorophyll were taken at various stages as well as panicles from the harvested canes. Dried kernels at 14% moisture content were also weighed at various stages. Chlorophyll, grain weight, absolute ethanol volume, juice volume, cane yield, and brix showed significant (p=0.05 differences for genotypes as well as the stages of harvesting. Results from this study showed that harvesting sweet sorghum at stages IV and V (104 to 117 days after planting would be appropriate for production of kernels and ethanol. EUSS10 has the highest ethanol potential (1062.78 l ha−1 due to excellent juice volume (22976.9 l ha−1 and EUSS11 (985.26 l ha−1 due to its high brix (16.21.

  18. A compact ball screw based electromagnetic energy harvester for railroad application

    Science.gov (United States)

    Pan, Yu; Lin, Teng; Liu, Cheng; Yu, Jie; Zuo, Jianyong; Zuo, Lei

    2018-03-01

    To enable the smart technologies, such as the positive train controls, rail damage detection and track health monitoring on the railroad side, the electricity is required and in needed. In this paper, we proposed a novel ball-screw based electromagnetic energy harvester for railway track with mechanical-motion-rectifier (MMR) mechanism, to harvest the energy that usually dissipated and wasted during train induced track vibration. Ball screw based design reduces backlash during motion transmission, and MMR nonlinear characteristics with one way clutches makes the harvester convert the bi-direction track vibration into a generator's unidirectional rotation, which improves the transmission reliability and increases the energy harvesting efficiency. A systematic model combining train-rail-harvester was established to analyze the dynamic characteristic of the proposed railway energy, and lab and in-field tests were carried out to experimentally characterize the proposed energy harvester. In lab bench test showed the proposed harvester reached a 70% mechanical efficiency with a high sensitivity to the environment vibration. In filed test showed that a peak 7.8W phase power was achieved when a two marshaling type A metro train passed by with a 30 km/h.

  19. Mems-based pzt/pzt bimorph thick film vibration energy harvester

    DEFF Research Database (Denmark)

    Xu, Ruichao; Lei, Anders; Dahl-Petersen, Christian

    2011-01-01

    We describe fabrication and characterization of a significantly improved version of a MEMS-based PZT/PZT thick film bimorph vibration energy harvester with an integrated silicon proof mass. The main advantage of bimorph vibration energy harvesters is that strain energy is not lost in mechanical...... support materials since only PZT is strained, and thus it has a potential for significantly higher output power. An improved process scheme for the energy harvester resulted in a robust fabrication process with a record high fabrication yield of 98.6%. Moreover, the robust fabrication process allowed...... a high pressure treatment of the screen printed PZT thick films prior to sintering, improving the PZT thick film performance and harvester power output reaches 37.1 μW at 1 g....

  20. Fabrication and characterization of MEMS-based PZT/PZT bimorph thick film vibration energy harvesters

    DEFF Research Database (Denmark)

    Xu, Ruichao; Lei, Anders; Dahl-Petersen, Christian

    2012-01-01

    We describe the fabrication and characterization of a significantly improved version of a microelectromechanical system-based PZT/PZT thick film bimorph vibration energy harvester with an integrated silicon proof mass; the harvester is fabricated in a fully monolithic process. The main advantage...... yield of 98%. The robust fabrication process allowed a high pressure treatment of the screen printed PZT thick films prior to sintering. The high pressure treatment improved the PZT thick film performance and increased the harvester power output to 37.1 μW at 1 g root mean square acceleration. We also...... characterize the harvester performance when only one of the PZT layers is used while the other is left open or short circuit....

  1. Production economics of harvesting young hardwood stands in central Appalachia

    Science.gov (United States)

    Yaoxiang Li; Jingxin Wang; Gary W. Miller; Joe McNeel

    2004-01-01

    Three harvesting systems of chainsaw/cable skidder, fell-buncher/grapple skidder, and harvester/forwarder were simulated in harvesting three hardwood stands of 30 to 50 years old in central Appalachia. Stands were generated by using a stand generator and harvesting prescriptions included clearcut, shelterwood cut, selective cut, diameter limit cut, and crop tree...

  2. Smart multi-application energy harvester using Arduino | Rizman ...

    African Journals Online (AJOL)

    This paper presents a Smart Multi-App Harvester Energy Using Arduino for energy harvesting. The system consists of a few mechanical parts such as solar, thermal plate and dynamo (for kinetic) to harvest the energy. The objectives of the project are to harvest the wasted energy from the mechanical parts and used it as a ...

  3. Harvesting and processing of microalgae biomass fractions for biodiesel production

    International Nuclear Information System (INIS)

    Munir, M.; Sharif, N.; Naz, S.; Saleem, F.; Manzoor, F.

    2013-01-01

    There has been a recent resurgent interest in microalgae as an oil producer for biofuel applications. An adequate supply of nutrients and carbon dioxide enables algae to successfully transform light energy of the sun into energy - rich chemical compounds through photosynthesis. A strain with high lipids, successfully grown and harvested, could provide oil for most of our process by volume, which would then provide the most profitable output. Significant advances have also been made in upstream processing to generate cellular biomass and oil. However, the process of extracting and purifying of oil from algae continues to prove a significant challenge in producing both microalgae bioproducts and biofuel, as the oil extraction from algae is relatively energy-intensive and expensive. The aim of this review is to focus on different harvesting and extraction processes of algae for biodiesel production reported within the last decade. (author)

  4. Novel piezoelectric bistable oscillator architecture for wideband vibration energy harvesting

    International Nuclear Information System (INIS)

    Liu, W Q; Badel, A; Formosa, F; Wu, Y P; Agbossou, A

    2013-01-01

    Bistable vibration energy harvesters are attracting more and more interest because of their capability to scavenge energy over a large frequency band. The bistable effect is usually based on magnetic interaction or buckled beams. This paper presents a novel architecture based on amplified piezoelectric structures. This buckled spring–mass architecture allows the energy of the dynamic mass to be converted into electrical energy in the piezoelectric materials as efficiently as possible. Modeling and design are performed and a normalized expression of the harvester behavior is given. Chirp and band-limited noise excitations are used to evaluate the proposed harvester’s performances. Simulation and experimental results are in good agreement. A method of using a spectrum plot for investigating the interwell motion is presented. The effect of the electric load impedance matching strategy is also studied. Results and comparisons with the literature show that the proposed device combines a large bandwidth and a high power density. (paper)

  5. A Belleville-spring-based electromagnetic energy harvester

    International Nuclear Information System (INIS)

    Castagnetti, Davide

    2015-01-01

    Energy harvesting from kinetic ambient energy is particularly effective to power autonomous sensors. This work proposes an innovative energy converter based on two counteracting Belleville springs and exploiting their peculiarity, for a height to thickness ratio equal to 1.414, of nearly zero stiffness over a wide deflection range. After analytical and numerical modelling a prototype is developed and experimentally investigated. The sub-optimal geometry of the commercial springs used in the prototype, together with a non-ideal response, makes the operating frequency for the prototype higher than in analytical and numerical predictions. Nevertheless, the harvester exhibits a significantly large bandwidth, together with a high output power, compared to similar solutions in the literature, for all the examined configurations and input excitations. (paper)

  6. Evaluation of harvest and information needs for North American sea ducks.

    Directory of Open Access Journals (Sweden)

    Mark D Koneff

    Full Text Available Wildlife managers routinely seek to establish sustainable limits of sport harvest or other regulated forms of take while confronted with considerable uncertainty. A growing body of ecological research focuses on methods to describe and account for uncertainty in management decision-making and to prioritize research and monitoring investments to reduce the most influential uncertainties. We used simulation methods incorporating measures of demographic uncertainty to evaluate risk of overharvest and prioritize information needs for North American sea ducks (Tribe Mergini. Sea ducks are popular game birds in North America, yet they are poorly monitored and their population dynamics are poorly understood relative to other North American waterfowl. There have been few attempts to assess the sustainability of harvest of North American sea ducks, and no formal harvest strategy exists in the U.S. or Canada to guide management. The popularity of sea duck hunting, extended hunting opportunity for some populations (i.e., special seasons and/or bag limits, and population declines have led to concern about potential overharvest. We used Monte Carlo simulation to contrast estimates of allowable harvest and observed harvest and assess risk of overharvest for 7 populations of North American sea ducks: the American subspecies of common eider (Somateria mollissima dresseri, eastern and western populations of black scoter (Melanitta americana and surf scoter (M. perspicillata, and continental populations of white-winged scoter (M. fusca and long-tailed duck (Clangula hyemalis. We combined information from empirical studies and the opinions of experts through formal elicitation to create probability distributions reflecting uncertainty in the individual demographic parameters used in this assessment. Estimates of maximum growth (rmax, and therefore of allowable harvest, were highly uncertain for all populations. Long-tailed duck and American common eider appeared

  7. Low power acoustic harvesting of aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Kaduchak, G. (Gregory); Sinha, D. N. (Dipen N)

    2001-01-01

    A new acoustic device for levitation and/or concentration of aerosols and sniall liquid/solid samples (up to several millimeters in diameter) in air has been developed. The device is inexpensive, low-power, and, in its simplest embodiment, does not require accurate alignmen1 of a resonant cavity. It is constructed from a cylindrical PZT tube of outside diameter D = 19.0 mm and thickness-to-radius ratio h/a - 0.03. The lowest-order breathing mode of the tube is tuned to match a resonant mode of the interior air-filled cylindrical cavity. A high Q cavity results that can be driven efficiently. An acoustic standing wave is created in the inteirior cavity of the cylindrical shell where particle concrmtration takes place at the nodal planes of the field. It is shown that drops of water in excess of 1 mm in diameter may be levitated against the force of gravity for approxirnately 100 mW of input electrical power. The main objective of the research is to implement this lowpower device to concentrate and harvest aerosols in a flowing system. Several different cavity geonietries iwe presented for efficient collection of 1 he conaartratetl aerosols. Concentraiion factors greater than 40 iue demonstrated for particles of size 0.7 1.1 in a flow volume of 50 L/minute.

  8. Rain-induced spring wheat harvest losses

    Science.gov (United States)

    Bauer, A.; Black, A. L. (Principal Investigator)

    1983-01-01

    When rain or a combination of rain and high humidity delay wheat harvest, losses can occur in grain yield and/or grain quality. Yield losses can result from shattering, from reduction in test weight, and in the case of windrowed grain, from rooting of sprouting grain at the soil: windrow contact. Losses in grain quality can result from reduction in test weight and from sprouting. Sprouting causes a degradation of grain proteins and starches, hence flour quality is reduced, and the grain price deteriorates to the value of feed grain. Although losses in grain yield and quality are rain-induced, these losses do not necessarily occur because a standing or windrowed crop is wetted by rain. Spike water concentration in hard red spring wheat must be increased to about 45-49% before sprouting is initiated in grain that has overcome dormancy. The time required to overcome this dormancy after the cultivar has dried to 12 to 14% water concentration differs with hard red spring cultivars. The effect of rain on threshing-ready standing and windrowed hard red spring wheat grain yeild and quality was evaluated. A goal was to develop the capability to forecast the extent of expected loss of grain yield and quality from specific climatic events that delay threshing.

  9. The cost of silage harvest and transport systems for herbaceous crops

    Energy Technology Data Exchange (ETDEWEB)

    Turhollow, A.; Downing, M. [Oak Ridge National Lab., TN (United States); Butler, J. [Butler (James), Tifton, GA (United States)

    1996-12-31

    Some of the highest yielding herbaceous biomass crops are thick- stemmed species. Their relatively high moisture content necessitates they be handled and stored as silage rather than hay bales or modules. This paper presents estimated costs of harvesting and transporting herbaceous crops as silage. Costs are based on an engineering- economic approach. Equipment costs are estimated by combining per hour costs with the hours required to complete the operation. Harvest includes severing, chopping, and blowing stalks into a wagon or truck.

  10. Managing the forest for more than the trees: effects of experimental timber harvest on forest Lepidoptera.

    Science.gov (United States)

    Summerville, Keith S

    2011-04-01

    Studies of the effects of timber harvest on forest insect communities have rarely considered how disturbance from a range of harvest levels interacts with temporal variation in species diversity to affect community resistance to change. Here I report the results of a landscape-scale, before-and-after, treatment-control experiment designed to test how communities of forest Lepidoptera experience (1) changes in species richness and composition and (2) shifts in species dominance one year after logging. I sampled Lepidoptera from 20 forest stands allocated to three harvest treatments (control, even-aged shelterwood or clearcuts, and uneven-aged group selection cuts) within three watersheds at Morgan-Monroe State Forest, Indiana, USA. Moths were sampled from all forest stands one year prior to harvest in 2007 and immediately post-harvest in 2009. Species composition was most significantly affected by temporal variation between years, although uneven-aged management also caused significant changes in lepidopteran community structure. Furthermore, species richness of Lepidoptera was higher in 2007 compared to 2009 across all watersheds and forest stands. The decrease in species richness between years, however, was much larger in even-aged and uneven-aged management units compared to the control. Furthermore, matrix stands within the even-aged management unit demonstrated the highest resistance to species loss within any management unit. Species dominance was highly resistant to effects of timber harvest, with pre- and post-harvest values for Simpson diversity nearly invariant. Counter to prediction, however, the suite of dominant taxa differed dramatically among the three management units post-harvest. My results suggest that temporal variation may have strong interactions with timber harvest, precipitating loss of nearly 50% species richness from managed stands regardless of harvest level. Even-aged management, however, appeared to leave the smallest "footprint" on moth

  11. Strong antenna-enhanced fluorescence of a single light-harvesting complex shows photon anti-bunching

    NARCIS (Netherlands)

    Wientjes, E.; Renger, J.; Curto, A.G.; Cogdell, R.; Hulst, van N.F.

    2014-01-01

    The nature of the highly efficient energy transfer in photosynthetic light-harvesting complexes is a subject of intense research. Unfortunately, the low fluorescence efficiency and limited photostability hampers the study of individual light-harvesting complexes at ambient conditions. Here we

  12. Evidence for coherent mixing of excited and charge-transfer states in the major plant light-harvesting antenna, LHCII

    NARCIS (Netherlands)

    Ramanan, Charusheela; Ferretti, Marco; van Roon, Henny; Novoderezhkin, Vladimir I.; van Grondelle, Rienk

    2017-01-01

    LHCII, the major light harvesting antenna from plants, plays a dual role in photosynthesis. In low light it is a light-harvester, while in high light it is a quencher that protects the organism from photodamage. The switching mechanism between these two orthogonal conditions is mediated by protein

  13. Harvest-related edge effects on prey availability and foraging of hooded warblers in a bottomland hardwood forest

    Science.gov (United States)

    John C. Kilgo

    2005-01-01

    The effects of harvest-created canopy gaps in bottomland hardwood forests on arthropod abundance and, hence, the foraging ecology of birds are poorly understood. I predicted that arthropod abundance would be high near edges of group-selection harvest gaps and lower in the surrounding forest, and that male Hooded Warblers (Wilsonia citrina) foraging...

  14. An electroactive polymer energy harvester for wireless sensor networks

    International Nuclear Information System (INIS)

    McKay, T G; Rosset, S; Shea, H; Anderson, I A

    2013-01-01

    This paper reports the design, fabrication, and testing of a soft electroactive polymer power generator that has a volume of 1cm 3 . The generator provides an opportunity to harvest energy from environmental sources to power wireless sensor networks because it can harvest from low frequency motions, is compact, and lightweight. Electroactive polymers are highly stretchable variable capacitors. Electrical energy is produced when the deformation of a stretched, charged electroactive polymer is relaxed; like-charges are compressed together and opposite-charges are pushed apart, resulting in an increased voltage. Although electroactive polymers have impressively displayed energy densities as high as 550 mJ/g, they have been based on films with thicknesses of tens to hundreds of micrometers, thus a generator covering a large area would be required to provide useful power. Energy harvesters covering large areas are inconvenient to deploy in a wireless sensor network with a large number of nodes, so a generator that is compact in all three dimensions is required. In this work we fabricated a generator that can fit within a 11×11×9 mm envelope by stacking 42, 11mm diameter generator films on top of each other. When compressed cyclically at a rate of 0.5 Hz our generator produced 300 uW of power which is a sufficient amount of power for a low power wireless sensor node. The combination of our generator's small form factor and ability to harvest useful energy from low frequency motions provides an opportunity to deploy large numbers of wireless sensor nodes without the need for periodic, costly battery replacement

  15. Suitability of Water Harvesting in the Upper Blue Nile Basin, Ethiopia: A First Step towards a Mesoscale Hydrological Modeling Framework

    Directory of Open Access Journals (Sweden)

    Yihun T. Dile

    2016-01-01

    Full Text Available Extreme rainfall variability has been one of the major factors to famine and environmental degradation in Ethiopia. The potential for water harvesting in the Upper Blue Nile Basin was assessed using two GIS-based Multicriteria Evaluation methods: (1 a Boolean approach to locate suitable areas for in situ and ex situ systems and (2 a weighted overlay analysis to classify suitable areas into different water harvesting suitability levels. The sensitivity of the results was analyzed to the influence given to different constraining factors. A large part of the basin was suitable for water harvesting: the Boolean analysis showed that 36% of the basin was suitable for in situ and ex situ systems, while the weighted overlay analysis showed that 6–24% of the basin was highly suitable. Rainfall has the highest influence on suitability for water harvesting. Implementing water harvesting in nonagricultural land use types may further increase the benefit. Assessing water harvesting suitability at the larger catchment scale lays the foundation for modeling of water harvesting at mesoscale, which enables analysis of the potential and implications of upscaling of water harvesting practices for building resilience against climatic shocks. A complete water harvesting suitability study requires socioeconomic analysis and stakeholder consultation.

  16. EU mitigation potential of harvested wood products.

    Science.gov (United States)

    Pilli, Roberto; Fiorese, Giulia; Grassi, Giacomo

    2015-12-01

    The new rules for the Land Use, Land Use Change and Forestry sector under the Kyoto Protocol recognized the importance of Harvested Wood Products (HWP) in climate change mitigation. We used the Tier 2 method proposed in the 2013 IPCC KP Supplement to estimate emissions and removals from HWP from 1990 to 2030 in EU-28 countries with three future harvest scenarios (constant historical average, and +/-20% in 2030). For the historical period (2000-2012) our results are consistent with other studies, indicating a HWP sink equal on average to -44.0 Mt CO 2 yr -1 (about 10% of the sink by forest pools). Assuming a constant historical harvest scenario and future distribution of the total harvest among each commodity, the HWP sink decreases to -22.9 Mt CO 2 yr -1 in 2030. The increasing and decreasing harvest scenarios produced a HWP sink of -43.2 and -9.0 Mt CO 2 yr -1 in 2030, respectively. Other factors may play an important role on HWP sink, including: (i) the relative share of different wood products, and (ii) the combined effect of production, import and export on the domestic production of each commodity. Maintaining a constant historical harvest, the HWP sink will slowly tend to saturate, i.e. to approach zero in the long term. The current HWP sink will be maintained only by further increasing the current harvest; however, this will tend to reduce the current sink in forest biomass, at least in the short term. Overall, our results suggest that: (i) there is limited potential for additional HWP sink in the EU; (ii) the HWP mitigation potential should be analyzed in conjunction with other mitigation components (e.g. sink in forest biomass, energy and material substitution by wood).

  17. Optical fiber stripper positioning apparatus

    Science.gov (United States)

    Fyfe, Richard W.; Sanchez, Jr., Amadeo

    1990-01-01

    An optical fiber positioning apparatus for an optical fiber stripping device is disclosed which is capable of providing precise axial alignment between an optical fiber to be stripped of its outer jacket and the cutting blades of a stripping device. The apparatus includes a first bore having a width approximately equal to the diameter of an unstripped optical fiber and a counter bore axially aligned with the first bore and dimensioned to precisely receive a portion of the stripping device in axial alignment with notched cutting blades within the stripping device to thereby axially align the notched cutting blades of the stripping device with the axis of the optical fiber to permit the notched cutting blades to sever the jacket on the optical fiber without damaging the cladding on the optical fiber. In a preferred embodiment, the apparatus further includes a fiber stop which permits determination of the length of jacket to be removed from the optical fiber.

  18. Design optimization of harvester head and actuation system of forest harvester

    DEFF Research Database (Denmark)

    Andersen, Torben Ole; Hansen, Michael R.; Mouritsen, Ole Ø.

    2005-01-01

    This paper is on the analysis and subsequent efficiency optimization of a forrest harvester. As basis for the optimization the existing machine has undergone substantial experimental testing with a view to determine the loading that the harvester head is subjected to and also the corresponding...

  19. Broadband piezoelectric energy harvesting using nonlinear magnetic forces; Bandbreitensteigerung von piezoelektrischen Energy Harvesting Systemen durch Magnetkraefte

    Energy Technology Data Exchange (ETDEWEB)

    Westermann, Henrik; Neubauer, Marcus; Wallaschek, Joerg [Hannover Univ. (Germany). Inst. fuer Dynamik und Schwingungen

    2012-07-15

    Using ambient energy by piezoelectric energy harvesting systems received much attention over the last years. Most vibration-based generators produce a sufficient power only if the transducer is excited in its resonance frequency. The use of magnetic forces suggests a promising strategy to increase the efficiency. This paper presents different ways for broadband piezoelectric energy harvesting using nonlinear magnetic forces. (orig.)

  20. Tropical forest harvesting and taxation: a dynamic model of harvesting behavior under selective extraction systems

    Science.gov (United States)

    Robert F. Conrad; Malcolm Gillis; D. Evan Mercer

    2005-01-01

    A dynamic model of selective harvesting in multi-species,multi-age tropical forests is developed. Forests are predicted to exhibit different optimal harvesting profiles depending on the nature of their joint cost functions and own or cross-species stock effects. The model is applied to the controversy about incentives produced by various taxes. The impacts of specific...

  1. 75 FR 3888 - Migratory Bird Subsistence Harvest in Alaska; Harvest Regulations for Migratory Birds in Alaska...

    Science.gov (United States)

    2010-01-25

    ...-0082; 91200-1231-9BPP-L2] RIN 1018-AW67 Migratory Bird Subsistence Harvest in Alaska; Harvest Regulations for Migratory Birds in Alaska During the 2010 Season AGENCY: Fish and Wildlife Service, Interior... Service, are reopening the public comment period on our proposed rule to establish migratory bird...

  2. Harvesting of short rotation coppice. Harvesting trials with a cut and storage system in Germany

    Energy Technology Data Exchange (ETDEWEB)

    Schweier, J.; Becker, G.

    2012-11-01

    Short rotation coppice (SRC) harvesting techniques are available in Germany, but broad experience and knowledge about machine performance and the related effective costs of harvesting operations are still missing. This information is crucial, as harvesting costs strongly influence the economic performance of the overall supply chain. Therefore, it was the aim of this study to collect and analyze productivity data of different harvesting systems for SRC. The combined cut and chip system on the one hand and the cut and storage system on the other hand were studied by literature review. Several studies analyze the combined cut and chip systems and the reported machine productivities showed great variations. The average was 30 green tons per scheduled machine hour (gt smh{sup -1}). Few studies are analysing the cut and storage system. They report that machines still are under development and that further research is needed. Therefore, time studies of harvesting operations using the cut and storage system were carried out. Five trials were performed with the harvesting machine 'Stemster MK III' developed by Nordic Biomass. The share of productive working time was 85% and the average productivity was 21 gt smh{sup -1}. These results were compared with values from the literature. Resulting harvesting costs were calculated per oven dry ton (Euro odt{sup -1}). The advantages and disadvantages of both harvesting systems are highlighted. (orig.)

  3. Assessment of rainwater harvesting potential using GIS

    Science.gov (United States)

    Hari, Durgasrilakshmi; Ramamohan Reddy, K.; Vikas, Kola; Srinivas, N.; Vikas, G.

    2018-03-01

    Rainwater harvesting (RWH) is one of the best practices to overcome the scarcity of water. Rainwater harvesting involves collection and storage of rainwater locally through different technologies, for future use. It is also useful for livestock, groundwater recharge and for irrigation practices. Potential of rainwater harvesting refers to the capacity of an individual catchment that harnesses the water falling on the catchment during a particular year considering all rainy days. The present study deals with the identification of the study area boundary and marking it as a Polygon in Google Earth Pro Later, Rooftops of various house entities and roads were digitized using the Polygon command in Google Earth Pro. GIS technique is employed for locating boundaries of the study area and for calculating the areas of various types of rooftops and roads. With the application of GIS, it is possible to assess the total potential of water that can be harvested. The present study will enable us to identify the suitable type of water harvesting structure along with the number of structures required. It is extremely an ideal and effective solution to overcome the water crisis through water conservation in the study area.

  4. A novel bistable energy harvesting concept

    International Nuclear Information System (INIS)

    Scarselli, G; Nicassio, F; Pinto, F; Ciampa, F; Iervolino, O; Meo, M

    2016-01-01

    Bistable energy harvesting has become a major field of research due to some unique features for converting mechanical energy into electrical power. When properly loaded, bistable structures snap-through from one stable configuration to another, causing large strains and consequently power generation. Moreover, bistable structures can harvest energy across a broad-frequency bandwidth due to their nonlinear characteristics. Despite the fact that snap-through may be triggered regardless of the form or frequency of exciting vibration, the external force must reach a specific snap-through activation threshold value to trigger the transition from one stable state to another. This aspect is a limiting factor for realistic vibration energy harvesting application with bistable devices. This paper presents a novel power harvesting concept for bistable composites based on a ‘lever effect’ aimed at minimising the activation force to cause the snap through by choosing properly the bistable structures’ constraints. The concept was demonstrated with the help of numerical simulation and experimental testing. The results showed that the actuation force is one order of magnitude smaller (3%–6%) than the activation force of conventionally constrained bistable devices. In addition, it was shown that the output voltage was higher than the conventional configuration, leading to a significant increase in power generation. This novel concept could lead to a new generation of more efficient bistable energy harvesters for realistic vibration environments. (paper)

  5. Nanoscale piezoelectric vibration energy harvester design

    Science.gov (United States)

    Foruzande, Hamid Reza; Hajnayeb, Ali; Yaghootian, Amin

    2017-09-01

    Development of new nanoscale devices has increased the demand for new types of small-scale energy resources such as ambient vibrations energy harvesters. Among the vibration energy harvesters, piezoelectric energy harvesters (PEHs) can be easily miniaturized and fabricated in micro and nano scales. This change in the dimensions of a PEH leads to a change in its governing equations of motion, and consequently, the predicted harvested energy comparing to a macroscale PEH. In this research, effects of small scale dimensions on the nonlinear vibration and harvested voltage of a nanoscale PEH is studied. The PEH is modeled as a cantilever piezoelectric bimorph nanobeam with a tip mass, using the Euler-Bernoulli beam theory in conjunction with Hamilton's principle. A harmonic base excitation is applied as a model of the ambient vibrations. The nonlocal elasticity theory is used to consider the size effects in the developed model. The derived equations of motion are discretized using the assumed-modes method and solved using the method of multiple scales. Sensitivity analysis for the effect of different parameters of the system in addition to size effects is conducted. The results show the significance of nonlocal elasticity theory in the prediction of system dynamic nonlinear behavior. It is also observed that neglecting the size effects results in lower estimates of the PEH vibration amplitudes. The results pave the way for designing new nanoscale sensors in addition to PEHs.

  6. Refreshing Music: Fog Harvesting with Harps

    Science.gov (United States)

    Shi, Weiwei; Anderson, Mark; Kennedy, Brook; Boreyko, Jonathan

    2017-11-01

    Fog harvesting is a useful technique for obtaining fresh water in arid climates. The wire meshes currently utilized for fog harvesting suffer from dual constraints: coarse meshes cannot efficiently capture fog, while fine meshes suffer from clogging issues. Here, we design a new type of fog harvester comprised of an array of vertical wires, which we call ``fog harps.'' To investigate the water collection efficiency, three fog harps were designed with different diameters (254 μm, 508 μm and 1.30 mm) but the same pitch-to-diameter ratio of 2. For comparison, three different size meshes were purchased with equivalent dimensions. As expected for the mesh structures, the mid-sized wires performed the best, with a drop-off in performance for the fine or coarse meshes. In contrast, the fog harvesting rate continually increased with decreasing wire diameter for the fog harps, due to its low hysteresis that prevented droplet clogging. This resulted in a 3-fold enhancement in the fog harvesting rate for the harp form factor compared to the mesh. The lack of a performance ceiling for the harps suggest that even greater enhancements could be achieved by scaling down to yet smaller sizes.

  7. Nonlinear dynamics of a circular piezoelectric plate for vibratory energy harvesting

    Science.gov (United States)

    Yuan, Tian-Chen; Yang, Jian; Chen, Li-Qun

    2018-06-01

    Nonlinear behaviors are investigated for a vibration-based energy harvester. The harvester consists of a circular composite plate with the clamped boundary, a proof mass and two steel rings. The lumped parameter model of the harvester is established and the parameters are identified from the experiment. The measured nonlinear behaviors can be approximately described by the lumped model. Both the experimental and the numerical results demonstrate that the circular plate harvester has soft characteristics under low excitation and both hard characteristics and soft characteristics under high excitation. The experimental results show that the output voltage can achieve over 35 V (about 50 mW) and more than 14 Hz of bandwidth with 25 kΩ load resistance.

  8. EHRA: Specification and Analysis of Energy-Harvesting Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Dung, Phan Anh; Hansen, Michael Reichhardt; Madsen, Jan

    2014-01-01

    Although energy consumption of wireless sensor network has been studied extensively, we are far behind in understanding the dynamics of the power consumption along with energy production using harvesters. We introduce Energy Harvesting Routing Analysis (EHRA) as a formal modelling framework...... to study wireless sensor networks (WSN) with energy-harvesting capabilities. The purpose of the framework is to analyze WSNs at a high level of abstraction, that is, before the protocols are implemented and before the WSN is deployed. The conceptual basis of EHRA comprises the environment, the medium...... is developed as a simulator implemented using the functional programming language F#. This simulator is used to analyze global properties of WSNs such as network fragmentation,routing trends, and energy profiles for the nodes. Three routing protocols, with a progression in the energy-harvesting awareness...

  9. Dynamic and energetic characteristics of a bistable piezoelectric vibration energy harvester with an elastic magnifier

    Science.gov (United States)

    Wang, Guangqing; Liao, Wei-Hsin; Yang, Binqiang; Wang, Xuebao; Xu, Wentan; Li, Xiuling

    2018-05-01

    Bistable piezoelectric energy harvesters are being increasingly seen as an alternative to batteries in low-power devices. However, their energy harvesting characteristics are limited. To enhance these, we use a configuration including an elastic magnifier to amplify base excitation and provide sufficient kinetic energy to overcome potential well barriers, thus leading to large-amplitude bistable motion. We derive the distributed parameter mathematical model of this configuration by using Hamilton's principle. We then investigate the nonlinear dynamic behaviors and energetic characteristics and analyze the bifurcation for the equilibrium solution of the model. The simulations and experiments show high electromechanical responses and energy generation characteristics of the proposed system over a broad frequency band. The results suggest that, compared with a typical bistable piezoelectric energy harvester, the proposed energy harvester system with an elastic magnifier can provide higher output over a broader frequency band at lower excitation levels by adjusting the system's mass and stiffness ratios.

  10. Orientation of bluff body for designing efficient energy harvesters from vortex-induced vibrations

    International Nuclear Information System (INIS)

    Dai, H. L.; Abdelkefi, A.; Yang, Y.; Wang, L.

    2016-01-01

    The characteristics and performances of four distinct vortex-induced vibrations (VIVs) piezoelectric energy harvesters are experimentally investigated and compared. The difference between these VIV energy harvesters is the installation of the cylindrical bluff body at the tip of cantilever beam with different orientations (bottom, top, horizontal, and vertical). Experiments show that the synchronization regions of the bottom, top, and horizontal configurations are almost the same at low wind speeds (around 1.5 m/s). The vertical configuration has the highest wind speed for synchronization (around 3.5 m/s) with the largest harvested power, which is explained by its highest natural frequency and the smallest coupled damping. The results lead to the conclusion that to design efficient VIV energy harvesters, the bluff body should be aligned with the beam for low wind speeds (<2 m/s) and perpendicular to the beam at high wind speeds (>2 m/s)

  11. Influence of the harvesting time, temperature and drying period on basil (Ocimum basilicum L. essential oil

    Directory of Open Access Journals (Sweden)

    José Luiz S. Carvalho Filho

    Full Text Available Ocimum basilicum L. essential oil with high concentration of linalool is valuable in international business. O. basilicum essential oil is widely used as seasoning and in cosmetic industry. To assure proper essential oil yield and quality, it is crucial to determine which environmental and processing factors are affecting its composition. The goal of our work is to evaluate the effects of harvesting time, temperature, and drying period on the yield and chemical composition of O. basilicum essential oil. Harvestings were performed 40 and 93 days after seedling transplantation. Harvesting performed at 8:00 h and 12:00 h provided higher essential oil yield. After five days drying, the concentration of linalool raised from 45.18% to 86.80%. O. basilicum should be harvested during morning and the biomass dried at 40ºC for five days to obtain linalool rich essential oil.

  12. Impact-driven, frequency up-converting coupled vibration energy harvesting device for low frequency operation

    International Nuclear Information System (INIS)

    Gu, Lei; Livermore, Carol

    2011-01-01

    This paper presents experiments and models of an energy harvesting device in which a low frequency resonator impacts a high frequency energy harvesting resonator, resulting in energy harvesting predominantly at the system's coupled vibration frequency. Analysis shows that a reduced mechanical damping ratio during coupled vibration enables increased electrical power generation as compared with conventional technology. Experiments demonstrate that the efficiency of electrical power transfer is significantly improved with the coupled vibration approach. An average power output of 0.43 mW is achieved under 0.4g acceleration at 8.2 Hz, corresponding to a power density of 25.5 µW cm −3 . The measured power and power density at the resonant frequency are respectively 4.8 times and 13 times the measured peak values for a conventional harvester created from a low frequency beam alone

  13. MECHANIZED HARVESTING TESTS PERFORMED BY GRAPE HARVESTERS IN SUPER INTENSIVE OLIVE ORCHARD CULTIVATION IN SPAIN

    Directory of Open Access Journals (Sweden)

    Gennaro Giametta

    2009-06-01

    Full Text Available Today also those countries boasting a century-old olive growing tradition have to look at the latest, most dynamic, non labour-intensive olive growing systems to abate production (notably, harvesting operations costs and remain competitive in a globalized market. This is why over the last few years super intensive olive orchard cultivation has been attracting a lot of interest on the part of olive growers all over the world as it accounts for an innovative model whereby olive groves are tailored to the special needs of grape harvesters. This paper reports the first results of experimental mechanical harvesting tests in a super-intensive olive cultivation. The study is intended to explore both productivity and work capacity of two of the most commonly used grape harvesters, Grégoire G120SW and New Holland Braud VX680, in a view to assessing their harvesting performance by a series of tests conducted in Spain. On the basis of the tests it was possible to verify that the machines are able to detach the almost all the drupes (more than 90%, with one only passage, and this independently of both size and location of drupes on the tree crown and of their maturity stage. Using these machines, two people can often carry out the whole harvest process: an operator driving the harvester and another person transferring the fruit from the harvester in the field to the olive oil mill for processing. With this system, the work speed is usually, in the best working conditions, about 1.7 km/hour and the average harvesting time is about 2.5-3 hours/ha. For the time being it is however impossible to draw definitive conclusions in terms of performance of the above cultivation systems and harvesting machines. Additional key observational studies are needed in the years to come to assess the efficiency of the entire model.

  14. Progress and Design Concerns of Nanostructured Solar Energy Harvesting Devices.

    Science.gov (United States)

    Leung, Siu-Fung; Zhang, Qianpeng; Tavakoli, Mohammad Mahdi; He, Jin; Mo, Xiaoliang; Fan, Zhiyong

    2016-05-01

    Integrating devices with nanostructures is considered a promising strategy to improve the performance of solar energy harvesting devices such as photovoltaic (PV) devices and photo-electrochemical (PEC) solar water splitting devices. Extensive efforts have been exerted to improve the power conversion efficiencies (PCE) of such devices by utilizing novel nanostructures to revolutionize device structural designs. The thicknesses of light absorber and material consumption can be substantially reduced because of light trapping with nanostructures. Meanwhile, the utilization of nanostructures can also result in more effective carrier collection by shortening the photogenerated carrier collection path length. Nevertheless, performance optimization of nanostructured solar energy harvesting devices requires a rational design of various aspects of the nanostructures, such as their shape, aspect ratio, periodicity, etc. Without this, the utilization of nanostructures can lead to compromised device performance as the incorporation of these structures can result in defects and additional carrier recombination. The design guidelines of solar energy harvesting devices are summarized, including thin film non-uniformity on nanostructures, surface recombination, parasitic absorption, and the importance of uniform distribution of photo-generated carriers. A systematic view of the design concerns will assist better understanding of device physics and benefit the fabrication of high performance devices in the future. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Broadband energy harvesting using acoustic black hole structural tailoring

    International Nuclear Information System (INIS)

    Zhao, Liuxian; Semperlotti, Fabio; Conlon, Stephen C

    2014-01-01

    This paper explores the concept of an acoustic black hole (ABH) as a main design framework for performing dynamic structural tailoring of mechanical systems for vibration energy harvesting applications. The ABH is an integral feature embedded in the host structure that allows for a smooth reduction of the phase velocity, theoretically approaching zero, while minimizing the reflected energy. This mechanism results in structural areas with high energy density that can be effectively exploited to develop enhanced vibration-based energy harvesting. Fully coupled electro-mechanical models of an ABH tapered structure with surface mounted piezo-transducers are developed to numerically simulate the response of the system to both steady state and transient excitations. The design performances are numerically evaluated using structural intensity data as well as the instantaneous voltage/power and energy output produced by the piezo-transducer network. Results show that the dynamically tailored structural design enables a drastic increase in the harvested energy as compared to traditional structures, both under steady state and transient excitation conditions. (papers)

  16. FOCIH: Form-Based Ontology Creation and Information Harvesting

    Science.gov (United States)

    Tao, Cui; Embley, David W.; Liddle, Stephen W.

    Creating an ontology and populating it with data are both labor-intensive tasks requiring a high degree of expertise. Thus, scaling ontology creation and population to the size of the web in an effort to create a web of data—which some see as Web 3.0—is prohibitive. Can we find ways to streamline these tasks and lower the barrier enough to enable Web 3.0? Toward this end we offer a form-based approach to ontology creation that provides a way to create Web 3.0 ontologies without the need for specialized training. And we offer a way to semi-automatically harvest data from the current web of pages for a Web 3.0 ontology. In addition to harvesting information with respect to an ontology, the approach also annotates web pages and links facts in web pages to ontological concepts, resulting in a web of data superimposed over the web of pages. Experience with our prototype system shows that mappings between conceptual-model-based ontologies and forms are sufficient for creating the kind of ontologies needed for Web 3.0, and experiments with our prototype system show that automatic harvesting, automatic annotation, and automatic superimposition of a web of data over a web of pages work well.

  17. Laser scanning measurements on trees for logging harvesting operations.

    Science.gov (United States)

    Zheng, Yili; Liu, Jinhao; Wang, Dian; Yang, Ruixi

    2012-01-01

    Logging harvesters represent a set of high-performance modern forestry machinery, which can finish a series of continuous operations such as felling, delimbing, peeling, bucking and so forth with human intervention. It is found by experiment that during the process of the alignment of the harvesting head to capture the trunk, the operator needs a lot of observation, judgment and repeated operations, which lead to the time and fuel losses. In order to improve the operation efficiency and reduce the operating costs, the point clouds for standing trees are collected with a low-cost 2D laser scanner. A cluster extracting algorithm and filtering algorithm are used to classify each trunk from the point cloud. On the assumption that every cross section of the target trunk is approximate a standard circle and combining the information of an Attitude and Heading Reference System, the radii and center locations of the trunks in the scanning range are calculated by the Fletcher-Reeves conjugate gradient algorithm. The method is validated through experiments in an aspen forest, and the optimized calculation time consumption is compared with the previous work of other researchers. Moreover, the implementation of the calculation result for automotive capturing trunks by the harvesting head during the logging operation is discussed in particular.

  18. Triboelectric-thermoelectric hybrid nanogenerator for harvesting frictional energy

    Science.gov (United States)

    Kim, Min-Ki; Kim, Myoung-Soo; Jo, Sung-Eun; Kim, Yong-Jun

    2016-12-01

    The triboelectric nanogenerator, an energy harvesting device that converts external kinetic energy into electrical energy through using a nano-structured triboelectric material, is well known as an energy harvester with a simple structure and high output voltage. However, triboelectric nanogenerators also inevitably generate heat resulting from the friction that arises from their inherent sliding motions. In this paper, we present a hybrid nanogenerator, which integrates a triboelectric generator and a thermoelectric generator (TEG) for harvesting both the kinetic friction energy and the heat energy that would otherwise be wasted. The triboelectric part consists of a polytetrafluoroethylene (PTFE) film with nano-structures and a movable aluminum panel. The thermoelectric part is attached to the bottom of the PTFE film by an adhesive phase change material layer. We confirmed that the hybrid nanogenerator can generate an output power that is higher than that generated by a single triboelectric nanogenerator or a TEG. The hybrid nanogenerator was capable of producing a power density of 14.98 mW cm-2. The output power, produced from a sliding motion of 12 cm s-1, was capable of instantaneously lighting up 100 commercial LED bulbs. The hybrid nanogenerator can charge a 47 μF capacitor at a charging rate of 7.0 mV s-1, which is 13.3% faster than a single triboelectric generator. Furthermore, the efficiency of the device was significantly improved by the addition of a heat source. This hybrid energy harvester does not require any difficult fabrication steps, relative to existing triboelectric nanogenerators. The present study addresses a method for increasing the efficiency while solving other problems associated with triboelectric nanogenerators.

  19. Feasibility of Energy Harvesting Using a Piezoelectric Tire

    Science.gov (United States)

    Malotte, Christopher

    While the piezoelectric effect has been around for some time, it has only recently caught interest as a potential sustainable energy harvesting device. Piezoelectric energy harvesting has been developed for shoes and panels, but has yet to be integrated into a marketable bicycle tire. For this thesis, the development and feasibility of a piezoelectric tire was done. This includes the development of a circuit that incorporates piezoceramic elements, energy harvesting circuitry, and an energy storage device. A single phase circuit was designed using an ac-dc diode rectifier. An electrolytic capacitor was used as the energy storage device. A financial feasibility was also done to determine targets for manufacturing cost and sales price. These models take into account market trends for high performance tires, economies of scale, and the possibility of government subsidies. This research will help understand the potential for the marketability of a piezoelectric energy harvesting tire that can create electricity for remote use. This study found that there are many obstacles that must be addressed before a piezoelectric tire can be marketed to the general public. The power output of this device is minuscule compared to an alkaline battery. In order for this device to approach the power output of an alkaline battery the weight of the device would also become an issue. Additionally this device is very costly compared to the average bicycle tire. Lastly, this device is extreme fragile and easily broken. In order for this device to become marketable the issues of power output, cost, weight, and durability must all be successfully overcome.

  20. Erosi Tanah Akibat Operasi Pemanenan Hutan (Soil Erosion Caused by Forest Harvesting Operations

    Directory of Open Access Journals (Sweden)

    Ujang Suwarna

    2011-05-01

    Full Text Available Forest harvesting operation has been known as an activity that should be considered as the main cause of soil erosion. Indonesia, the second largest owner of tropical forest, should have a serious consideration to the operation.  Therefore, the study was conducted in logged over area of a natural production forest.  The objectives of the study was to examine level of soil erosion caused by forest harvesting operations and to analyze a strategy to control level of the erosion based on its influencing factors. The study showed that forest harvesting operations caused soil erosion.  Factors that influenced the high level of the erosion were high level of precipitation, lack on planning of forest harvesting operations, no applying treatment of cross drain and cover crop in the new skidding roads, no culture of carefulness in the operations, and low human resource capacity in applying environmentally friendly forest harvesting techniques. Keywords: soil erosion, forest harvesting, logged over area, skidding road

  1. Architectures for wrist-worn energy harvesting

    Science.gov (United States)

    Rantz, R.; Halim, M. A.; Xue, T.; Zhang, Q.; Gu, L.; Yang, K.; Roundy, S.

    2018-04-01

    This paper reports the simulation-based analysis of six dynamical structures with respect to their wrist-worn vibration energy harvesting capability. This work approaches the problem of maximizing energy harvesting potential at the wrist by considering multiple mechanical substructures; rotational and linear motion-based architectures are examined. Mathematical models are developed and experimentally corroborated. An optimization routine is applied to the proposed architectures to maximize average power output and allow for comparison. The addition of a linear spring element to the structures has the potential to improve power output; for example, in the case of rotational structures, a 211% improvement in power output was estimated under real walking excitation. The analysis concludes that a sprung rotational harvester architecture outperforms a sprung linear architecture by 66% when real walking data is used as input to the simulations.

  2. Subwavelength resonant antennas enhancing electromagnetic energy harvesting

    Science.gov (United States)

    Oumbe Tekam, Gabin; Ginis, Vincent; Seetharamdoo, Divitha; Danckaert, Jan

    2016-04-01

    In this work, an electromagnetic energy harvester operating at microwave frequencies is designed based on a cut- wire metasurface. This metamaterial is known to contain a quasistatic electric dipole resonator leading to a strong resonant electric response when illuminated by electromagnetic fields.1 Starting from an equivalent electrical circuit, we analytically design the parameters of the system to tune the resonance frequency of the harvester at the desired frequency band. Subsequently, we compare these results with numerical simulations, which have been obtained using finite elements numerical simulations. Finally, we optimize the design by investigating the best arrangement for energy harvesting by coupling in parallel and in series many single layers of cut-wire metasurfaces. We also discuss the implementation of different geometries and sizes of the cut-wire metasurface for achieving different center frequencies and bandwidths.

  3. Forest harvesting systems friendly to the environment

    Energy Technology Data Exchange (ETDEWEB)

    Waesterlund, I [Swedish Univ. of Agricultural Sciences, Garpenberg (Sweden); Hassan, A E [North Carolina State Univ. Col. of Forest Resources, Raleigh, NC (United States)

    1995-09-01

    The trend in forestry practices today in Europe and U.S.A. in general and Scandinavian countries in particular, is towards adapting systems based on landscape planning. Thus common harvesting equipment available on the market will have to be replaced to meet these tough demands. Environmentalists recommend that wood fiber should be harvested either by selection cutting or commercial thinning thus leaving the site undisturbed with no sign of machine traffic. This mandate will preserve ground water quality and assist in soil conservation. However, to meet the pulp and paper as well as saw mill industries demand for wood from this method of cutting (selection or commercial thinning), requires a thorough examination of our harvesting systems and techniques. This paper will discuss present and future machines that are friendly to the environment. Hypothetical designs and improvements of existing machine systems will be addressed and recommendations will be made for future research activities. 75 refs, 8 figs, 1 tab

  4. Forest harvesting systems friendly to the environment

    International Nuclear Information System (INIS)

    Waesterlund, I.; Hassan, A.E.

    1995-01-01

    The trend in forestry practices today in Europe and U.S.A. in general and Scandinavian countries in particular, is towards adapting systems based on landscape planning. Thus common harvesting equipment available on the market will have to be replaced to meet these tough demands. Environmentalists recommend that wood fiber should be harvested either by selection cutting or commercial thinning thus leaving the site undisturbed with no sign of machine traffic. This mandate will preserve ground water quality and assist in soil conservation. However, to meet the pulp and paper as well as saw mill industries demand for wood from this method of cutting (selection or commercial thinning), requires a thorough examination of our harvesting systems and techniques. This paper will discuss present and future machines that are friendly to the environment. Hypothetical designs and improvements of existing machine systems will be addressed and recommendations will be made for future research activities. 75 refs, 8 figs, 1 tab

  5. Modeling the Effects of Harvest Alternatives on Mitigating Oak Decline in a Central Hardwood Forest Landscape.

    Directory of Open Access Journals (Sweden)

    Wen J Wang

    Full Text Available Oak decline is a process induced by complex interactions of predisposing factors, inciting factors, and contributing factors operating at tree, stand, and landscape scales. It has greatly altered species composition and stand structure in affected areas. Thinning, clearcutting, and group selection are widely adopted harvest alternatives for reducing forest vulnerability to oak decline by removing susceptible species and declining trees. However, the long-term, landscape-scale effects of these different harvest alternatives are not well studied because of the limited availability of experimental data. In this study, we applied a forest landscape model in combination with field studies to evaluate the effects of the three harvest alternatives on mitigating oak decline in a Central Hardwood Forest landscape. Results showed that the potential oak decline in high risk sites decreased strongly in the next five decades irrespective of harvest alternatives. This is because oak decline is a natural process and forest succession (e.g., high tree mortality resulting from intense competition would eventually lead to the decrease in oak decline in this area. However, forest harvesting did play a role in mitigating oak decline and the effectiveness varied among the three harvest alternatives. The group selection and clearcutting alternatives were most effective in mitigating oak decline in the short and medium terms, respectively. The long-term effects of the three harvest alternatives on mitigating oak decline became less discernible as the role of succession increased. The thinning alternative had the highest biomass retention over time, followed by the group selection and clearcutting alternatives. The group selection alternative that balanced treatment effects and retaining biomass was the most viable alternative for managing oak decline. Insights from this study may be useful in developing effective and informed forest harvesting plans for managing oak

  6. Three-dimensional thermal simulations of thin solid carbon foils for charge stripping of high current uranium ion beams at a proposed new heavy-ion linac at GSI

    Directory of Open Access Journals (Sweden)

    N. A. Tahir

    2014-04-01

    Full Text Available This paper presents an extensive numerical study of heating of thin solid carbon foils by 1.4  MeV/u uranium ion beams to explore the possibility of using such a target as a charge stripper at the proposed new Gesellschaft für Schwerionenforschung high energy heavy–ion linac. These simulations have been carried out using a sophisticated 3D computer code that accounts for physical phenomena that are important in this problem. A variety of beam and target parameters have been considered. The results suggest that within the considered parameter range, the target will be severely damaged by the beam. Thus, a carbon foil stripper does not seem to be a reliable option for the future Gesellschaft für Schwerionenforschung high energy heavy–ion linac, in particular, at FAIR design beam intensities.

  7. Harvesting to optimize fiber quality

    Science.gov (United States)

    Production conditions typical to the Texas High Plains region can produce cotton crops with high short fiber and nep content, both of which have a detrimental impact on ring spinning performance. Since Texas now produces over 50% of the U.S. cotton crop annually, it is critical that production and p...

  8. The family of light-harvesting-related proteins (LHCs, ELIPs, HLIPs): was the harvesting of light their primary function?

    Science.gov (United States)

    Montané, M H; Kloppstech, K

    2000-11-27

    Light-harvesting complex proteins (LHCs) and early light-induced proteins (ELIPs) are essential pigment-binding components of the thylakoid membrane and are encoded by one of the largest and most complex higher plant gene families. The functional diversification of these proteins corresponded to the transition from extrinsic (phycobilisome-based) to intrinsic (LHC-based) light-harvesting antenna systems during the evolution of chloroplasts from cyanobacteria, yet the functional basis of this diversification has been elusive. Here, we propose that the original function of LHCs and ELIPs was not to collect light and to transfer its energy content to the reaction centers but to disperse the absorbed energy of light in the form of heat or fluorescence. These energy-dispersing proteins are believed to have originated in cyanobacteria as one-helix, highly light-inducible proteins (HLIPs) that later acquired four helices through two successive gene duplication steps. We suggest that the ELIPs arose first in this succession, with a primary function in energy dispersion for protection of photosynthetic pigments from photo-oxidation. We consider the LHC I and II families as more recent and very successful evolutionary additions to this family that ultimately attained a new function, thereby replacing the ancestral extrinsic light-harvesting system. Our model accounts for the non-photochemical quenching role recently shown for higher plant psbS proteins.

  9. Managing harvest and habitat as integrated components

    Science.gov (United States)

    Osnas, Erik; Runge, Michael C.; Mattsson, Brady J.; Austin, Jane E.; Boomer, G. S.; Clark, R. G.; Devers, P.; Eadie, J. M.; Lonsdorf, E. V.; Tavernia, Brian G.

    2014-01-01

    In 2007, several important initiatives in the North American waterfowl management community called for an integrated approach to habitat and harvest management. The essence of the call for integration is that harvest and habitat management affect the same resources, yet exist as separate endeavours with very different regulatory contexts. A common modelling framework could help these management streams to better understand their mutual effects. Particularly, how does successful habitat management increase harvest potential? Also, how do regional habitat programmes and large-scale harvest strategies affect continental population sizes (a metric used to express habitat goals)? In the ensuing five years, several projects took on different aspects of these challenges. While all of these projects are still on-going, and are not yet sufficiently developed to produce guidance for management decisions, they have been influential in expanding the dialogue and producing some important emerging lessons. The first lesson has been that one of the more difficult aspects of integration is not the integration across decision contexts, but the integration across spatial and temporal scales. Habitat management occurs at local and regional scales. Harvest management decisions are made at a continental scale. How do these actions, taken at different scales, combine to influence waterfowl population dynamics at all scales? The second lesson has been that consideration of the interface of habitat and harvest management can generate important insights into the objectives underlying the decision context. Often the objectives are very complex and trade-off against one another. The third lesson follows from the second – if an understanding of the fundamental objectives is paramount, there is no escaping the need for a better understanding of human dimensions, specifically the desires of hunters and nonhunters and the role they play in conservation. In the end, the compelling question is

  10. Energy harvesting with piezoelectric and pyroelectric materials

    CERN Document Server

    Muensit, Nantakan

    2011-01-01

    The purpose of this book is to present the current state of knowledge in the field of energy harvesting using piezoelectric and pyroelectric materials. The book is addressed to students and academics engaged in research in the fields of energy harvesting, material sciences and engineering. Scientists and engineers who are working in the area of energy conservation and renewable energy resources should find it useful as well. Explanations of fundamental physical properties such as piezoelectricity and pyroelectricity are included to aid the understanding of the non-specialist. Specific technolo

  11. Vibration Energy Harvesting Potential for Turbomachinery Applications

    Directory of Open Access Journals (Sweden)

    Adrian STOICESCU

    2018-03-01

    Full Text Available The vibration energy harvesting process represents one of the research directions for increasing power efficiency of electric systems, increasing instrumentation nodes autonomy in hard to reach locations and decreasing total system mass by eliminating cables and higher-power adapters. Research based on the possibility of converting vibration energy into useful electric energy is used to evaluate the potential of its use on turbomachinery applications. Aspects such as the structure and characteristics of piezoelectric generators, harvesting networks, their setup and optimization, are considered. Finally, performance test results are shown using piezoelectric systems on a turbine engine.

  12. Materials in energy conversion, harvesting, and storage

    CERN Document Server

    Lu, Kathy

    2014-01-01

    First authored book to address materials' role in the quest for the next generation of energy materials Energy balance, efficiency, sustainability, and so on, are some of many facets of energy challenges covered in current research. However, there has not been a monograph that directly covers a spectrum of materials issues in the context of energy conversion, harvesting and storage. Addressing one of the most pressing problems of our time, Materials in Energy Conversion, Harvesting, and Storage illuminates the roles and performance requirements of materials in energy an

  13. Electronically droplet energy harvesting using piezoelectric cantilevers

    KAUST Repository

    Al Ahmad, Mahmoud Al

    2012-01-01

    A report is presented on free falling droplet energy harvesting using piezoelectric cantilevers. The harvester incorporates a multimorph clamped-free cantilever which is composed of five layers of lead zirconate titanate piezoelectric thick films. During the impact, the droplet kinetic energy is transferred into the form of mechanical stress forcing the piezoelectric structure to vibrate. Experimental results show energy of 0.3 μJ per droplet. The scenario of moderate falling drop intensity, i.e. 230 drops per second, yields a total energy of 400 μJ. © 2012 The Institution of Engineering and Technology.

  14. Vivaldi Antenna for RF Energy Harvesting

    Directory of Open Access Journals (Sweden)

    J. Schneider

    2016-12-01

    Full Text Available Energy harvesting is a future technology for capturing ambient energy from the environment to be recycled to feed low-power devices. A planar antipodal Vivaldi antenna is presented for gathering energy from GSM, WLAN, UMTS and related applications. The designed antenna has the potential to be used in energy harvesting systems. Moreover, the antenna is suitable for UWB applications, because it operates according to FCC regulations (3.1 – 10.6 GHz. The designed antenna is printed on ARLON 600 substrate and operates in frequency band from 0.810 GHz up to more than 12 GHz. Experimental results show good conformity with simulated performance.

  15. Early harvesting of the vascularized pedicled nasoseptal flap during endoscopic skull base surgery.

    Science.gov (United States)

    Eloy, Jean Anderson; Patel, Amit A; Shukla, Pratik A; Choudhry, Osamah J; Liu, James K

    2013-01-01

    The vascularized pedicled nasoseptal flap (PNSF) represents a successful option for reconstruction of large skull base defects after expanded endoscopic endonasal approaches (EEA). This vascularized flap can be harvested early or late in the operation depending on the anticipation of high-flow CSF leaks. Each harvesting technique (early vs. late) is associated with different advantages and disadvantages. In this study, we evaluate our experience with early harvesting of the PNSF for repair of large skull base defects after EEA. A retrospective review was performed at a tertiary care medical center on patients who underwent early PNSF harvesting during reconstruction of intraoperative high-flow CSF leaks after EEA between December 2008 and March 2012. Demographic data, repair materials, surgical approach, and incidence of PNSF usage were collected. Eighty-seven patients meeting the inclusion criteria were identified. In 86 procedures (98.9%), the PNSF harvested at the beginning of the operation was used. In 1 case (1.1%), the PNSF was not used because a high-flow intraoperative CSF leak was not encountered. This patient had recurrence of intradural disease 8months later, and the previously elevated PNSF was subsequent used after tumor resection. Based on our data, a high-flow CSF leak and need for a PNSF can be accurately anticipated in patients undergoing EEA for skull base lesions. Because of the advantages of early harvesting of the PNSF and the high preoperative predictive value of CSF leak anticipations, this technique represents a feasible harvesting practice for EEA surgeries. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Comparison of PZN-PT, PMN-PT single crystals and PZT ceramic for vibration energy harvesting

    International Nuclear Information System (INIS)

    Yang, Zhengbao; Zu, Jean

    2016-01-01

    Highlights: • Systematic analysis of PMN-PT and PZN-PT single crystals for energy harvesters. • Performance analysis and comparison under various conditions. • Discussion of the effect of the SSHI technique on single crystal energy harvesters. • Efficiency analysis in both on-resonance and off-resonance conditions. - Abstract: Vibration energy harvesting has a great potential to achieve self-powered operations for wireless sensors, wearable devices and medical electronics, and thus has attracted much attention in academia and industry. The majority of research into this subject has focused on the piezoelectric effect of synthetic materials, especially the perovskite PZT ceramics. Recently the new-generation piezoelectric materials PMN-PT and PZN-PT single crystals have gained significant interest because of their outstanding piezoelectric properties. They can be used to replace the widely-adopted PZT ceramics for improving energy harvesters’ performance substantially. However, there is little research on comparing PMN-PT and PZN-PT energy harvesters against PZT harvesters. In this paper, we present a systematic comparison between vibration energy harvesters using the PMN-PT, PZN-PT single crystals and those using the PZT ceramics. Key properties of the three materials are summarized and compared. The performance of the PMN-PT and PZN-PT energy harvesters is characterized under different conditions (beam length, resistance, frequency, excitation strength, and backward coupling effect), and is quantitatively compared with the PZT counterpart. Furthermore, the effect of the synchronized switch harvesting on inductor (SSHI) circuit on the three harvesters is discussed. The experimental results indicate that energy harvesters using the PMN-PT and PZN-PT single crystals can significantly outperform those using the PZT ceramics. This study provides a strong base for future research on high-performance energy harvesters using the new PMN-PT and PZN-PT single

  17. Galfenol Energy Harvesting Device Proposal

    Energy Technology Data Exchange (ETDEWEB)

    Lograsso, Thomas [Ames Lab., Ames, IA (United States); Jones, Lawrence [Ames Lab., Ames, IA (United States); Xing, Qingfeng [Ames Lab., Ames, IA (United States)

    2016-06-29

    This CRADA involved an integrated approach of synthesizing Fe-Ga (Galfenol) powder using high-pressure gas atomization (HPGA) and 3D printing via laser engineered net shaping (LENS) processing to produce free standing magnetostricitve sensors.

  18. Development of multi-functional combine harvester with grain harvesting and straw baling

    International Nuclear Information System (INIS)

    Tang, Z.; Li, Y.; Cheng, C.

    2017-01-01

    The decomposition and burning of straw results in serious environmental pollution, and research is needed to improve strategies for straw collection to reduce pollution. This work presents an integrated design of multi-functional rice combine harvester that allows grain harvesting and straw baling. This multi-functional combine harvester could reduce the energy consumption required for rice harvesting and simplify the process of harvesting and baling. The transmission schematic, matching parameters and the rotation speed of threshing cylinder and square baler were designed and checked. Then the evaluation of grain threshing and straw baling were tested on a transverse threshing cylinders device tes rig and straw square bales compression test rig. The test results indicated that, with a feeding rate of 3.0 kg/s, the remaining straw flow rate at the discharge outlet was only 1.22 kg/s, which indicates a variable mass threshing process by the transverse threshing cylinder. Then the optimal diameter, length and rotating speed of multi-functional combine harvester transverse threshing cylinder were 554 mm, 1590 mm, and 850 r/min, respectively. The straw bale compression rotating speed of crank compression slider and piston was 95 r/min. Field trials by the multi-functional combine harvester formed bales with height×width×length of 40×50×54-63 cm, bale mass of 22.5 to 26.0 kg and bale density 206 to 216 kg/m3. This multi-functional combine harvester could be used for stem crops (such as rice, wheat and soybean) grain harvesting and straw square baling, which could reduce labor cost and power consumption.

  19. Development of multi-functional combine harvester with grain harvesting and straw baling

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Z.; Li, Y.; Cheng, C.

    2017-09-01

    The decomposition and burning of straw results in serious environmental pollution, and research is needed to improve strategies for straw collection to reduce pollution. This work presents an integrated design of multi-functional rice combine harvester that allows grain harvesting and straw baling. This multi-functional combine harvester could reduce the energy consumption required for rice harvesting and simplify the process of harvesting and baling. The transmission schematic, matching parameters and the rotation speed of threshing cylinder and square baler were designed and checked. Then the evaluation of grain threshing and straw baling were tested on a transverse threshing cylinders device tes rig and straw square bales compression test rig. The test results indicated that, with a feeding rate of 3.0 kg/s, the remaining straw flow rate at the discharge outlet was only 1.22 kg/s, which indicates a variable mass threshing process by the transverse threshing cylinder. Then the optimal diameter, length and rotating speed of multi-functional combine harvester transverse threshing cylinder were 554 mm, 1590 mm, and 850 r/min, respectively. The straw bale compression rotating speed of crank compression slider and piston was 95 r/min. Field trials by the multi-functional combine harvester formed bales with height×width×length of 40×50×54-63 cm, bale mass of 22.5 to 26.0 kg and bale density 206 to 216 kg/m3. This multi-functional combine harvester could be used for stem crops (such as rice, wheat and soybean) grain harvesting and straw square baling, which could reduce labor cost and power consumption.

  20. Energy harvesting by means of flow-induced vibrations on aerospace vehicles

    Science.gov (United States)

    Li, Daochun; Wu, Yining; Da Ronch, Andrea; Xiang, Jinwu

    2016-10-01

    This paper reviews the design, implementation, and demonstration of energy harvesting devices that exploit flow-induced vibrations as the main source of energy. Starting with a presentation of various concepts of energy harvesters that are designed to benefit from a general class of flow-induced vibrations, specific attention is then given at those technologies that may offer, today or in the near future, a potential benefit to extend the operational capabilities and to monitor critical parameters of unmanned aerial vehicles. Various phenomena characterized by flow-induced vibrations are discussed, including limit cycle oscillations of plates and wing sections, vortex-induced and galloping oscillations of bluff bodies, vortex-induced vibrations of downstream structures, and atmospheric turbulence and gusts. It was found that linear or linearized modeling approaches are commonly employed to support the design phase of energy harvesters. As a result, highly nonlinear and coupled phenomena that characterize flow-induced vibrations are neglected in the design process. The Authors encourage a shift in the current design paradigm: considering coupled nonlinear phenomena, and adequate modeling tools to support their analysis, from a design limitation to a design opportunity. Special emphasis is placed on identifying designs and implementations applicable to aircraft configurations. Application fields of flow-induced vibrations-based energy harvesters are discussed including power supply for wireless sensor networks and simultaneous energy harvest and control. A large body of work on energy harvesters is included in this review journal. Whereas most of the references claim direct applications to unmanned aerial vehicles, it is apparent that, in most of the cases presented, the working principles and characteristics of the energy harvesters are incompatible with any aerospace applications. Finally, the challenges that hold back the integration of energy harvesting